Combined Electro-acupuncture with Liver Artery Intubation in Treatment of Massive Liver Cancer

Hepatobiliary & Pancreatic Diseases International : HBPD INT. Aug, 2002  |  Pubmed ID: 14607714

To investigate the clinical effectiveness of electro-acupuncture therapy (EAT) in combination with liver artery intubation chemotherapy for massive liver cancer.

A Clinicopathological Study of Three Cases of Severe Acute Respiratory Syndrome (SARS)

Pathology. Dec, 2003  |  Pubmed ID: 14660106

The severe acute respiratory syndrome (SARS) caused a large outbreak of atypical pneumonia in Beijing, China from early March 2003. We report the pathological features from three patients who died of SARS.

Pathological Study on Severe Acute Respiratory Syndrome

Chinese Medical Journal. Jul, 2003  |  Pubmed ID: 12890365

To study the pathological characteristics of severe acute respiratory syndrome (SARS) and its relationship to clinical manifestation.

A Physiological Theory of Depth Perception from Vertical Disparity

Vision Research. Jan, 2003  |  Pubmed ID: 12505608

It has been known since the time of Helmholtz that vertical differences between the two retinal images can generate depth perception. Although many ecologically and geometrically inspired theories have been proposed, the neural mechanisms underlying the phenomenon remain elusive. Here we propose a new theory for depth perception from vertical disparity based on the oriented binocular receptive fields of visual cortical cells and on the radial bias of the preferred-orientation distribution in the cortex. The theory suggests that oriented cells may treat a vertical disparity as a weaker, equivalent horizontal disparity. It explains the induced effect, and the quadrant and size dependence of vertical disparity. It predicts that horizontal and vertical disparities should locally enhance or cancel each other according to their depth signs, and that the effect of vertical disparity should be orientation dependent. These predictions were confirmed through psychophysical experiments.

[A Clinicopathological Study on Nonalcoholic Steatohepatitis]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. Feb, 2003  |  Pubmed ID: 12648399

To observe the pathological and clinical characters of nonalcoholic steatohepatitis (NASH).

[A Clinicopathological Study on 3 Cases of Severe Acute Respiratory Syndrome]

Zhonghua Bing Li Xue Za Zhi Chinese Journal of Pathology. Jun, 2003  |  Pubmed ID: 12882681

To study the pathological characteristics of severe acute respiratory syndrome (SARS) and its relationship to clinical manifestation.

Both Monocular and Binocular Signals Contribute to Motion Rivalry

Vision Research. Jan, 2004  |  Pubmed ID: 14599570

There is an ongoing debate on whether binocular rivalry involves competition among monocular cells or binocular cells. We investigated this issue psychophysically with two specially designed test stimuli. One test stimulus contained monocular motion signals but greatly reduced binocular motion signals, while the other contained binocular motion signals but no monocular motion signals. For comparison, we also employed a normal rivalrous control containing both monocular and binocular motion signals, and a non-rivalrous flicker-noise control with neither monocular nor binocular motion signals. We found that binocular rivalry for the two test stimuli was significantly reduced compared with the normal rivalrous control, but not completely eliminated compared with the non-rivalrous control. Therefore, both monocular and binocular motion signals appear to contribute to motion rivalry, suggesting that motion rivalry must involve competition among both monocular and binocular cells.

Comparison of Quality of Life Between Urban and Rural Gastric Cancer Patients and Analysis of Influencing Factors

World Journal of Gastroenterology : WJG. Oct, 2004  |  Pubmed ID: 15378769

The conception of quality of life has been widely accepted by clinic doctors. Evaluations of the treatment effect of chronic diseases have been changed to depend not only on the survival time, but also on the quality of life of the patients. Fuzhou City and Changle County are high-incidence areas of the gastric cancer in Fujian Province. The aims of this research were to compare the quality of life of urban patients with that of rural patients and analyze the factors influencing quality of life of gastric cancer patients in Fujian Province.

[The Detection of Heat Shock Protein Gp96 in Primary Hepatocellular Carcinoma]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. Sep, 2004  |  Pubmed ID: 15387922

Effects of Attention on Motion Repulsion

Vision Research. May, 2005  |  Pubmed ID: 15733965

Motion repulsion involves interaction between two directions of motion. Since attention is known to bias interactions among different stimuli, we investigated the effect of attentional tasks on motion repulsion. We used two overlapping sets of random dots moving in different directions. When subjects had to detect a small speed-change or luminance change for dots along one direction, the repulsive influence from the other direction was significantly reduced compared with the control case without attentional tasks. However, when the speed-change could occur to either direction such that subjects had to attend both directions to detect the change, motion repulsion was not different from the control. A further experiment showed that decreasing the difficulty of the attentional task resulted in the disappearance of the attentional effect in the case of attention to one direction. Finally, over a wide range of contrasts for the unattended direction, attention reduced repulsion measured with the attended direction. These results are consistent with the physiological finding that strong attention to one direction of motion reduces inhibitory effects from the other direction.

A High-throughput Assay for Modulators of Ligand-gated Chloride Channels

Assay and Drug Development Technologies. Feb, 2005  |  Pubmed ID: 15798396

Invertebrate glutamate-gated chloride channels (GluCls) are important targets for anthelmintics and insecticides such as ivermectin. To facilitate screening for novel GluCl modulators, the Caenorhabditis elegans GluCl alpha2beta channel was chosen as a surrogate for parasite channels not yet cloned, and an inducible stable human embryonic kidney cell line was generated. Functional expression of the alpha2 and beta subunits was confirmed by whole-cell voltage clamp assays. Using this cell line, a high-throughput assay was developed that detects membrane potential changes associated with the activation of GluCls. In this assay, membrane depolarization was quantified via changes in fluorescence resonance energy transfer between two membrane-associated dyes. Robust and reproducible signals were detected in response to addition of glutamate or ivermectin. This assay was used for the screening of over 180,000 samples from natural and synthetic sources.

The Oblique Effect Depends on Perceived, Rather Than Physical, Orientation and Direction

Vision Research. Dec, 2005  |  Pubmed ID: 16023170

Observers can better discriminate orientation or direction near the cardinal axes than near an oblique axis. We investigated whether this well-known oblique effect is determined by the physical or the perceived axis of the stimuli. Using the simultaneous tilt illusion, we generated perceptually different orientations for the same inner (target) grating by contrasting it with differently oriented outer gratings. Subjects compared the target orientation with a set of reference orientations. If orientation discriminability was determined by the physical orientations, the psychometric curves for the same target grating would be identical. Instead, all subjects produced steeper curves when perceiving target gratings near vertically as opposed to more obliquely. This result of orientation discrimination was confirmed by using adaptation-generated tilt aftereffect to manipulate the perceived orientation of a given physical orientation. Moreover, we obtained the same result in direction discrimination by using motion repulsion to alter the perceived direction of a given physical direction. We conclude that when the perceived orientation or direction differs from the physical orientation or direction, the oblique effect depends on perceived, rather than physical, orientation or direction. Finally, as a by-product of the study, we found that, around the vertical direction, motion repulsion is much stronger when the inducing direction is more clockwise to the test direction than when it is more counterclockwise.

Influence of HBcAg in Liver Cell Plasma on Expression of Transforming Growth Factor-beta 1 in Liver Tissue of Low-grade Chronic Hepatitis B Patients

World Journal of Gastroenterology : WJG. Jan, 2006  |  Pubmed ID: 16440431

To study the influence of HBcAg on the expression of transforming growth factor-beta 1 (TGF-beta1) in liver tissue of low-grade chronic hepatitis B (CHB) patients.

Serial Analysis of Gene Expression in Progressing and Regressing Mouse Tumors Implicates the Involvement of RANTES and TARC in Antitumor Immune Responses

Molecular Therapy : the Journal of the American Society of Gene Therapy. Oct, 2006  |  Pubmed ID: 16807117

Previously we demonstrated that gene transduction of the granulocyte-macrophage colony stimulating-factor (GM-CSF) gene into mouse tumor cells eliminated tumorigenicity in vivo. The rejection process of the subcutaneous tumor was as follows: transient tumor growth peaked around 10 days after tumor injection, then the tumors were rejected within a week. In this paper, we analyzed the gene expression of the transiently established tumor masses by the serial analysis of gene expression method to identify molecules associated with the antitumor effect. We then screened those genes that were differentially expressed between the parental and the GM-CSF-transduced tumors and identified a group of genes that are suggested to have a relationship with tumor rejection, including a cytokine receptor, adhesion molecules, chemokines, cytotoxicity-related molecules, and others. Focusing on the chemokine genes TARC and RANTES, which were preferentially expressed in the GM-CSF-transduced tumors, their forced expression on mouse tumor cells showed moderate suppression of tumor formation. Transduction of GM-CSF in combination with either the TARC or the RANTES gene into tumor cells profoundly inhibited tumor establishment. Histological findings suggested the significant contribution of CD4+ T cells to tumor regression in both TARC/GM-CSF- and RANTES/GM-CSF-transduced tumor cells, in excess of that seen with GM-CSF transduction alone.

Cross-fixation Transfer of Motion Aftereffects with Expansion Motion

Vision Research. Oct, 2006  |  Pubmed ID: 16824574

It has been shown that motion aftereffect (MAE) not only is present at the adapted location but also partially transfers to nearby non-adapted locations. However, it is not clear whether MAE transfers across the fixation point. Since cells in area MSTd have receptive fields that cover both sides of the fixation point and since many MSTd cells, but not cells in earlier visual areas, prefer complex motion patterns such as expansion, we tested cross-fixation transfer of MAE induced by expanding random-dots stimuli. We also used rightward translational motion for comparison. Subjects adapted to motion patterns on a fixed side of the fixation point. Dynamic MAE was then measured with a nulling procedure at both the adapted site and the mirror site across the fixation point. Subjects' eye fixation during stimulus presentation was monitored with an infrared eye tracker. At the adapted site, both the expansion and the translation patterns generated strong MAEs, as expected. However, only the expansion pattern, but not translation pattern, generated significant MAE at the mirror site. This remained true even after we adjusted stimulus parameters to equate the strengths of the expansion MAE and translation MAE at the adapted site. We conclude that there is cross-fixation transfer of MAE for expansion motion but not for translational motion.

Fabrication and Characterization of Submicrometer- and Nanometer-sized Double-barrel Pipets

Analytical Chemistry. Oct, 2006  |  Pubmed ID: 17007531

Submicro- and nanometer-sized glass double-barrel pipets have been fabricated by a laser puller with new pulling programs and have been used to support submicro- and nanometer dual liquid/liquid interfaces. The smallest pipet that can be made by this approach is approximately 20 nm in radius. These pipets have been characterized by cyclic voltammetry and scanning electron microscopy. Generation/collection mode of charge-transfer reaction is demonstrated at the submicro- and nanometer dual-liquid/liquid interfaces. The dependence of collection efficiency upon geometric parameters of the pipets has been discussed. Among the micro-, submicro-, and nanopipets, we have found that the submicro-double-barrel pipets have higher collection efficiencies than that of others and are also very close to the values predicted by the theory. Therefore, in terms of G/C mode applications, the optimal size of double-barrel pipets should be in submicrometer scale. As one of the examples of special application, we have also demonstrated that in the case of no supporting electrolyte, only the nanometer double-barrel pipets can provide reasonably good G/C results.

[Relationship Between Oxidative Stress and Depression in Patients with Acute Leukemia]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Oct, 2006  |  Pubmed ID: 17096879

This study was aimed to investigate the relationships between oxidative stress and depression in patients with acute leukemia. Ninety two cases of acute leukemia were randomly enrolled in the study. Depressive disorder was assessed by self-rating depression scales (SDS) and multiple items questionaires. The total anti-oxidation capability (T-AOC), reactive oxygen species (ROS) and superoxide dismutase (SOD) activities, as well as malondialdehyde (MDA) and nitric oxide (NO) levels were measured in pre-treatment periods. Meanwhile, the steady state level of human 8-hydroxyguanine glycosylase (hOGG1) mRNA transcript was monitored by quantitative real-time PCR. The results showed that the defence of antioxidant system was impaired in patients with acute leukemia. The incidence of depression was 47.83% in 92 cases. T-AOC and SOD activities were significantly decreased in patients with depression, while ROS, NO, MDA levels and hOGG1 mRNA expression were reverse of the former. It revealed that depression positively correlated with course of disease and hOGG1, and negatively correlated with T-AOC. It is concluded that oxidative damage occurs in patients with acute leukemia, moreover, lower antioxidant defences exist in depressive patients. These results underscore the notion that oxidative stress may promote the development of depression.

A Low Prevalence of H Pylori and Endoscopic Findings in HIV-positive Chinese Patients with Gastrointestinal Symptoms

World Journal of Gastroenterology : WJG. Nov, 2007  |  Pubmed ID: 17907294

To compare the prevalence of H pylori infection, peptic ulcer, cytomegalovirus (CMV) infection and Candida esophagitis in human immunodeficiency virus (HIV)-positive and HIV-negative patients, and evaluate the impact of CD4 lymphocyte on H pylori and opportunistic infections.

The Changes of Oxidative Stress and Human 8-hydroxyguanine Glycosylase1 Gene Expression in Depressive Patients with Acute Leukemia

Leukemia Research. Mar, 2007  |  Pubmed ID: 16949154

The results of several recent studies indicated that free radicals are involved in the biochemical mechanisms that underlie neuropsychiatric disorders. In the present study, we evaluated changes in oxidative stress and human 8-hydroxyguanine glycosylase1 gene (hOGG1) expression in depressive patients with acute leukemia. Ninety two cases were assessed using the Zung self-rating depression scale (SDS) and multiple-item questionnaires. We measured total antioxidant capacity (T-AOC) and the concentrations of reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA) and nitric oxide (NO) during a pre-treatment period. The steady-state expression of hOGG1 mRNA transcripts was monitored. The incidence of depression was 47.83%. There was a significant decrease in serum T-AOC and SOD concentrations in depressive patients compared to the control subjects, whereas the opposite was the case for serum concentrations of ROS, NO and MDA. Real-time polymerase chain reaction (PCR) revealed that hOGG1 mRNA expression was greater in depressive patients than in the controls. Person correlation analysis revealed that depression was correlated positively with sex, the course of the disease and hOGG1 mRNA expression; depression was correlated negatively with T-AOC. Based on these results, we conclude that the antioxidant system is impaired in leukemic patients with affective disorders. Therefore, oxidative stress may play an important role in the pathophysiology of depression.

[Histopathological Changes in Livers of Patients with Chronic Severe Hepatitis B]

Zhonghua Gan Zang Bing Za Zhi = Zhonghua Ganzangbing Zazhi = Chinese Journal of Hepatology. May, 2007  |  Pubmed ID: 17524260

To investigate the histopathological features in livers of chronic severe hepatitis B (CSHB) patients.

Correlation Between Omental TNF-alpha Protein and Plasma PAI-1 in Obesity Subjects

International Journal of Cardiology. Aug, 2008  |  Pubmed ID: 17698217

The role of TNF-alpha in contributing to obesity-associated cardiovascular and metabolic risk has gained much attention.

Expression of TNF-alpha Protein in Omental and Subcutaneous Adipose Tissue in Obesity

Diabetes Research and Clinical Practice. Feb, 2008  |  Pubmed ID: 17935818

During the last several years the role of adipose tissue in contributing to obesity-associated cardiovascular and metabolic risk has gained much attention.

Distinctive MicroRNA Profiles Relating to Patient Survival in Esophageal Squamous Cell Carcinoma

Cancer Research. Jan, 2008  |  Pubmed ID: 18172293

Esophageal cancer is the sixth leading cause of death from cancer and one of the least studied cancers worldwide. The global microRNA expression profile of esophageal cancer has not been reported previously. Here, for the first time, we have investigated expressed microRNAs in cryopreserved esophageal cancer tissues using advanced microRNA microarray techniques. Our microarray analyses identified seven microRNAs that could distinguish malignant esophageal cancer lesions from adjacent normal tissues. Some microRNAs could be correlated with the different clinicopathologic classifications. High expression of hsa-miR-103/107 correlated with poor survival by univariate analysis as well as by multivariate analysis. These results indicate that microRNA expression profiles are important diagnostic and prognostic markers of esophageal cancer, which might be analyzed simply using economical approaches such as reverse transcription-PCR.

TARC and RANTES Enhance Antitumor Immunity Induced by the GM-CSF-transduced Tumor Vaccine in a Mouse Tumor Model

Cancer Immunology, Immunotherapy : CII. Sep, 2008  |  Pubmed ID: 18286286

Transduction of the granulocyte-macrophage colony stimulating factor (GM-CSF) gene into mouse tumor cells abrogates their tumorigenicity in vivo. Our previous report demonstrated that gene transduction of GM-CSF with either TARC or RANTES chemokines suppressed in vivo tumor formation. In this paper, we examined whether the addition of either recombinant TARC or RANTES proteins to irradiated GM-CSF-transduced tumor vaccine cells enhanced antitumor immunity against established mouse tumor models to examine its future clinical application.

Caspase-dependent Cleavage of BAG3 in Proteasome Inhibitors-induced Apoptosis in Thyroid Cancer Cells

Biochemical and Biophysical Research Communications. May, 2008  |  Pubmed ID: 18325327

Proteasome inhibitors are emerging as effective drugs for the treatment of relapsed/refractory multiple myeloma and possibly some solid tumors. Bcl-2-associated athanogene 3 (BAG3) is a survival protein that has been shown to be stimulated during cell response to stressful conditions, such as exposure to high temperature, heavy metals. We have recently demonstrated that BAG3 is also induced by proteasome inhibitors at the transcriptional level and the induction of BAG3 by proteasome inhibition is antiapoptotic. Here, we demonstrated that although proteasome inhibitors triggered similar upregulation of BAG3 transcript in sensitive and insensitive thyroid cancer cells, persistent increase of BAG3 protein was detected in insensitive cells, whereas less increase or even decrease was observed in sensitive cells. Notably, decrease of BAG3 protein was associated with the appearance of a BAG3 fragment of approximately 40kDa, which appeared to be caspase-dependent. Therefore, caspase-dependent cleavage of BAG3 might facilitate apoptosis in sensitive cells.

Involvement of the MADS-box Gene ZMM4 in Floral Induction and Inflorescence Development in Maize

Plant Physiology. Aug, 2008  |  Pubmed ID: 18539775

The switch from vegetative to reproductive growth is marked by the termination of vegetative development and the adoption of floral identity by the shoot apical meristem (SAM). This process is called the floral transition. To elucidate the molecular determinants involved in this process, we performed genome-wide RNA expression profiling on maize (Zea mays) shoot apices at vegetative and early reproductive stages using massively parallel signature sequencing technology. Profiling revealed significant up-regulation of two maize MADS-box (ZMM) genes, ZMM4 and ZMM15, after the floral transition. ZMM4 and ZMM15 map to duplicated regions on chromosomes 1 and 5 and are linked to neighboring MADS-box genes ZMM24 and ZMM31, respectively. This gene order is syntenic with the vernalization1 locus responsible for floral induction in winter wheat (Triticum monococcum) and similar loci in other cereals. Analyses of temporal and spatial expression patterns indicated that the duplicated pairs ZMM4-ZMM24 and ZMM15-ZMM31 are coordinately activated after the floral transition in early developing inflorescences. More detailed analyses revealed ZMM4 expression initiates in leaf primordia of vegetative shoot apices and later increases within elongating meristems acquiring inflorescence identity. Expression analysis in late flowering mutants positioned all four genes downstream of the floral activators indeterminate1 (id1) and delayed flowering1 (dlf1). Overexpression of ZMM4 leads to early flowering in transgenic maize and suppresses the late flowering phenotype of both the id1 and dlf1 mutations. Our results suggest ZMM4 may play roles in both floral induction and inflorescence development.

[Bioinformatic Analysis and Identification for a Novel Antigen MLAA-22 in Acute Monocytic Leukemia]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Jun, 2008  |  Pubmed ID: 18549609

This study was aimed to investigate a novel MLAA-22 antigen derived from a U937 cDNA library by the SEREX approach and search for gene expression in various samples. Bioinformatic analysis was performed to forecast MLAA-22 information mined from databases and experimental datasets. CTL epitope was predictied and the specific antibody for MLAA-22 was elicited by using peptide-microspheres and adjuvants. Furthermore, SYBR Green real-time PCR and immunoblotting method were used to evaluate the specificity of gene expression. The results showed that the full length cDNA of MLAA-22 located on chromosome 17q11.2 was 2.0 kb in size, and a putative protein was approximately 72.4 kD for 631 amino acids. The MLAA-22 encoded a cancer/testis antigen in human, which is nonsecreting type, plasmosin, labile protein, hydrophilia, thermostability, and without signal peptide. Many motifs might related to growth, proliferation, differentiation, and apoptosis. Antigenic peptides was synthesized as the antigen with Fmoc/PyBOP method. Rabbits were immunized by injecting the synthetic peptide-KLH to obtain antibody and the immune sera analyzed with ELISA were 1:8000. SYBR Green real-time PCR and Western blot showed that MLAA-22 presented with a higher number of copy messages in M(5), lower in CML, but not in gastric carcinoma, renal carcinoma, LNCaP cell lines and normal adult tissues, etc. It is concluded that mlaa-22 is a novel acute monocytic leukemia-associated antigen gene and be extended to further discovery.

A Genomic and Expression Compendium of the Expanded PEBP Gene Family from Maize

Plant Physiology. Jan, 2008  |  Pubmed ID: 17993543

The phosphatidylethanolamine-binding proteins (PEBPs) represent an ancient protein family found across the biosphere. In animals they are known to act as kinase and serine protease inhibitors controlling cell growth and differentiation. In plants the most extensively studied PEBP genes, the Arabidopsis (Arabidopsis thaliana) FLOWERING LOCUS T (FT) and TERMINAL FLOWER1 (TFL1) genes, function, respectively, as a promoter and a repressor of the floral transition. Twenty-five maize (Zea mays) genes that encode PEBP-like proteins, likely the entire gene family, were identified and named Zea mays CENTRORADIALIS (ZCN), after the first described plant PEBP gene from Antirrhinum. The maize family is expanded relative to eudicots (typically six to eight genes) and rice (Oryza sativa; 19 genes). Genomic structures, map locations, and syntenous relationships with rice were determined for 24 of the maize ZCN genes. Phylogenetic analysis assigned the maize ZCN proteins to three major subfamilies: TFL1-like (six members), MOTHER OF FT AND TFL1-like (three), and FT-like (15). Expression analysis demonstrated transcription for at least 21 ZCN genes, many with developmentally specific patterns and some having alternatively spliced transcripts. Expression patterns and protein structural analysis identified maize candidates likely having conserved gene function of TFL1. Expression patterns and interaction of the ZCN8 protein with the floral activator DLF1 in the yeast (Saccharomyces cerevisiae) two-hybrid assay strongly supports that ZCN8 plays an orthologous FT function in maize. The expression of other ZCN genes in roots, kernels, and flowers implies their involvement in diverse developmental processes.

Electrochemical DNAzyme Sensor for Lead Based on Amplification of DNA-Au Bio-bar Codes

Analytical Chemistry. Aug, 2008  |  Pubmed ID: 18627134

An electrochemical DNAzyme sensor for sensitive and selective detection of lead ion (Pb(2+)) has been developed, taking advantage of catalytic reactions of a DNAzyme upon its binding to Pb(2+) and the use of DNA-Au bio-bar codes to achieve signal enhancement. A specific DNAzyme for Pb(2+) is immobilized onto an Au electrode surface via a thiol-Au interaction. The DNAzyme hybridizes to a specially designed complementary substrate strand that has an overhang, which in turn hybridizes to the DNA-Au bio-bar code (short oligonucleotides attached to 13 nm gold nanoparticles). A redox mediator, Ru(NH3)6(3+), which can bind to the anionic phosphate of DNA through electrostatic interactions, serves as the electrochemical signal transducer. Upon binding of Pb(2+) to the DNAzyme, the DNAzyme catalyzes the hydrolytic cleavage of the substrate, resulting in the removal of the substrate strand along with the DNA bio-bar code and the bound Ru(NH3)6(3+) from the Au electrode surface. The release of Ru(NH3)6(3+) results in lower electrochemical signal of Ru(NH3)6(3+) confined on the electrode surface. Differential pulse voltammetry (DPV) signals of Ru(NH3)6(3+) provides quantitative measures of the concentrations of Pb(2+), with a linear calibration ranging from 5 nM to 0.1 microM. Because each nanoparticle carries a large number of DNA strands that bind to the signal transducer molecule Ru(NH3)6(3+), the use of DNA-Au bio-bar codes enhances the detection sensitivity by five times, enabling the detection of Pb(2+) at a very low level (1 nM). The DPV signal response of the DNAzyme sensor is negligible for other divalent metal ions, indicating that the sensor is highly selective for Pb(2+). Although this DNAzyme sensor is demonstrated for the detection of Pb(2+), it has the potential to serve as a general platform for design sensors for other small molecules and heavy metal ions.

Prediction of Compounds' Biological Function (metabolic Pathways) Based on Functional Group Composition

Molecular Diversity. May, 2008  |  Pubmed ID: 18704735

Efficient in silico screening approaches may provide valuable hints on biological functions of the compound-candidates, which could help to screen functional compounds either in basic researches on metabolic pathways or drug discovery. Here, we introduce a machine learning method (Nearest Neighbor Algorithm) based on functional group composition of compounds to the analysis of metabolic pathways. This method can quickly map small chemical molecules to the metabolic pathway that they likely belong to. A set of 2,764 compounds from 11 major classes of metabolic pathways were selected for study. The overall prediction rate reached 73.3%, indicating that functional group composition of compounds was really related to their biological metabolic functions.

Investigation of the Interactions Between Silver Nanoparticles and Hela Cells by Scanning Electrochemical Microscopy

The Analyst. Sep, 2008  |  Pubmed ID: 18709198

The interactions between Hela cells and silver nanoparticles (AgNPs) have been studied by scanning electrochemical microscopy (SECM) with both IrCl(6)(2-/3-) and Fe(CN)(6)(3-/4-) as the dual mediators. IrCl(6)(2-), which can be produced in situ and react with AgNPs, is used as the mediator between the AgNPs on the cells and the SECM tip. Another redox couple, Fe(CN)(6)(3-/4-), which has a similar hydrophilicity to IrCl(6)(2-/3-), but cannot react with AgNPs, is also employed for the contrast experiments. The cell array is cultured successfully onto a Petri dish by microcontact printing (muCP) technique, which can provide a basic platform for studying of single cells. The approach curve and line scan are the two methods of SECM employed here to study the Hela cells. The former can provide the information about the interaction between Hela cells and AgNPs whereas the later gives the cell imaging. The permeability of cell membranes and morphology are two main factors which have effects on the feedback mode signals when K(3)Fe(CN)(6) is used as the mediator. The permeability of the cell membranes can be ignored after interaction with high concentration of AgNP solution and the height of the Hela cells is slightly decreased in this process. The kinetic rate constants (k(0)) between IrCl(6)(2-) and Ag on the Hela cell can be evaluated using K(3)IrCl(6) as the mediator, and they are increased with the higher concentrations of the AgNP solutions. The k(0) is changed about 10 times from 0.43 +/- 0.04 x 10(-4) to 1.25 +/- 0.07 x 10(-4) and to 3.93 +/- 1.9 x 10(-4) cm s(-1) corresponding to 0, 1 and 5 mM of AgNO(3) solution. The experimental results demonstrate that the AgNPs can be adsorbed on the cell surface and detected by SECM. Thus, the amount of AgNPs adsorbed on cell membranes and the permeability or morphology changes can be investigated simultaneously using this approach. The dual mediator system and cell array fabricated by muCP technique can provide better reproducibility because they can simplify experiments, and provide a platform for further single cell detection.

Prolongation of Cardiac Allograft Survival by Syngeneic Hematopoietic Stem/progenitor Cell Transplantation in Mice

Advances in Therapy. Sep, 2008  |  Pubmed ID: 18758696

Organ transplantation is a rapidly developing field, being the only effective treatment for end-stage organ disease. However, the associated immunosuppressant therapy has numerous direct and indirect adverse effects. Hematopoietic stem cell transplantation (HSCT), via immune reconstitution, offers an alternative method of treatment. In this study, we determined the cardiac allograft survival in mice treated with syngeneic HSCT or hematopoietic progenitor cell transplantation (HPCT).

[Vaccination with Three HIV-1 Cross Neutralizing Epitopes Fused to HBV S Antigen Could Induce Robust Antibody Immune Response in Mice]

Bing Du Xue Bao = Chinese Journal of Virology / [bian Ji, Bing Du Xue Bao Bian Ji Wei Yuan Hui]. Jul, 2008  |  Pubmed ID: 18780627

To enhance immunogenicity of HIV-1 cross neutralizing epitopes , three HIV-1 cross neutralizing epitopes (ELDKWA, NWFDIT, GPGRAFY) were fused to 3' end of HBV S gene by PCR cloning technology, respectively. Three vaccinia virus (Tiantan strain) recombinants expressing separately the three fusion genes were subsequently constructed, named as RVJ1175S-2F5 (ELDKWA), RVJ1175S-4E10 (NWFDIT) and RVJ1175S-447-52D (GPGRAFY), respectively. From the supernatants of CEF cells infected by these vaccinia recombinants, three subunit vaccines (PS-2F5, PS-4E10 and PS-447-52D) were prepared after purification. Biology and immunology characteristics of these fusion antigens in vaccinia recombinants and subunit vaccines were comparatively studied. It was confirmed by PCR and sequencing that the fusion genes were inserted into the TK locus of vaccinia virus (Tiantan strain) correctly. The Fusion proteins were expressed efficiently and secreted into supernatant of the infected cells, which was demonstrated by HBsAg ELISA test. Two typical HBsAg bands of 23kD and 27kD were detected in all the purified samples by SDS-PAGE. These two bands were reacted well to HBsAb and corresponding HIV-1 monoclonal antibodies 2F5, 4E10 and 447-52D. BALB/c mice were immunized with subunit and vaccinia recombinant vaccines by intraperitoneal injection. High levels of HBsAb and anti-HIV-1 cross neutralizing epitope antibody in peripheral blood of immunized mice were tested by ELISA, and all the antibody titers induced by three subunit vaccines were higher than that induced by correlated vaccinia recombinants in mice. This work provides a basis for future study on neutralizing activity of these immunized sera and enhancing immune effect through the combined immunization with different type of vaccines.

Anion Transfer at a Micro-water/1,2-dichloroethane Interface Facilitated by Beta-octafluoro-meso-octamethylcalix[4]pyrrole

Journal of the American Chemical Society. Nov, 2008  |  Pubmed ID: 18839955

The facilitated transfer of four hydrophilic anions, i.e., Cl-, Br-, NO2-, and CH3CO2-, at the micro-water/1,2-dichloroethane interface supported at the tip of a micropipet has been observed successfully using beta-octafluoro-meso-octamethylcalix[4]pyrrole 2 as the receptor. We have also shown for the first time that the dynamics of this process can be studied by micropipet voltammetry. The standard kinetic rate constants (kdegrees) for facilitated anion transfer at such an interface were determined to be (2.11 +/- 0.90) x 10(-2) and (0.75 +/- 0.50) x 10(-2) cm/s in the case of Cl- and CH3CO2-, respectively. These values are much smaller than those associated with the facilitated transfer of analogous alkali metal ions. This difference is thought to reflect a number of underlying factors, including the higher hydration of anions as compared to similar sized cations. Studies such as these are expected to be useful in understanding the mechanism of anion transport at soft interfaces and for the design of yet-improved anion receptors and carriers.

Proteasome Inhibitor MG132 Induces BAG3 Expression Through Activation of Heat Shock Factor 1

Journal of Cellular Physiology. Mar, 2009  |  Pubmed ID: 19006120

BAG3 protein, a member of the BAG co-chaperones family, sustains cell survival in a variety of normal and neoplastic cell types, via its interaction with a variety of partners, such as the heat shock protein (HSP) 70, Bcl-2, Raf-1 and others. Expression of BAG3 is induced by some stressful stimuli, such as heat shock, heavy metal exposure. We have reported that proteasome inhibitors can also induce BAG3 expression at the transcriptional level and the induction of BAG3 compromises proteasome inhibitors-mediated apoptosis. However, the molecular mechanism of BAG3 upregulation has not been elucidated. In the current study, we provide evidence that heat shock transcription factor 1 (HSF1) is involved in BAG3 induction by proteasome inhibitor MG132. Using a series of varying lengths of 5'-flanking region of the BAG3 gene into luciferase reporter vectors, we found that MG132 stimulated the promoter activity via the -326/-233 and -825/-689 regions, which contains one putative heat shock-responsive element (HSE) for HSF1-binding, respectively. Site-directed deletion of the sites abrogated the enhanced reporter activity in response to MG132 treatment. Chromatin immunoprecipitation assay demonstrated that HSF1 directly bound to the MG132-responsive site on the BAG3 promoter. Activation of HSF1 occurred with MG132 along with BAG3 upregulation. Furthermore, knockdown HSF1 by small interfering RNA attenuated the BAG3 upregulation due to MG132.These results indicate that the proteasome inhibitor MG132 induces BAG3 expression through HSF1 activation.

Improved Catalytic Efficiency of Endo-beta-1,4-glucanase from Bacillus Subtilis BME-15 by Directed Evolution

Applied Microbiology and Biotechnology. Mar, 2009  |  Pubmed ID: 19050861

Bacillus subtilis endo-beta-1,4-glucanase (Cel5A) hydrolyzes cellulose by cleavage of the internal bonds in the glucose chains, producing new ends randomly. Using directed evolution techniques of error-prone polymerase chain reaction (PCR) and DNA shuffling, several Cel5A variants with improved catalytic activity had been screened from the mutant library, which contained 71,000 colonies. Compared with the wild-type enzyme, the variants (M44-11, S75 and S78) showed 2.03 to 2.68-fold increased activities toward sodium carboxymethyl cellulose (CMC), while the M44-11 also exhibited a wider pH tolerance and higher thermostability. Structural models of M44-11, S75, S78, and WT proteins revealed that most of the substitutions were not located in the strictly conserved regions, except the mutation V255A of S75, which was closed to the nucleophile Glu257 in the catalytic center of the enzyme. Moreover, V74A and D272G of M44-11, which were not located in the substrate binding sites and the catalytic center, might result in improved stability and catalytic activity. These results provided useful references for directed evolution of the enzymes that belonged to the glycoside hydrolase family 5 (GH5).

Significance of Survivin, Caspase-3, and VEGF Expression in Thyroid Carcinoma

Clinical and Experimental Medicine. Sep, 2009  |  Pubmed ID: 19205619

To investigate the clinical significance of survivin, caspase-3, and vascular endothelial growth factor expression in a subset of thyroid carcinoma and their correlation with prognosis. Sixty-eight cases of thyroid carcinoma (TC), 12 cases of thyroid adenoma (TA) and 10 cases of normal thyroid tissue (NT) were involved in immunohistochemical and real-time RT-PCR analyses for survivin, caspase-3, and VEGF expression. Statistical analyses were performed for differential expression among NT, TA and TC, correlations of their expression with the clinicopathological parameters of TC including histological typing, clinical staging and lymphnode metastasis, and relationship of survivin with caspase-3 or VEGF in TC. We observed higher mRNA expression and positive immunostaining for survivin and VEGF in TC compared with TA and NT, with a significant positive correlation among them and significant correlations with histological typing, clinical staging and lymphnode metastasis in TC, but we could not find any significance of caspase-3 in TC and its significant relationship with survivin expression. Our results indicate that survivin and VEGF are unfavorable molecules for TC evolution and prognosis, and possess positive correlation in TC.

Role of Oxidative Stress and Intracellular Glutathione in the Sensitivity to Apoptosis Induced by Proteasome Inhibitor in Thyroid Cancer Cells

BMC Cancer. 2009  |  Pubmed ID: 19216805

The proteasome inhibitor bortezomib has shown impressive clinical activity alone and in combination with conventional and other novel agents for the treatment of multiple myeloma (MM) and some solid cancers. Although bortezomib is known to be a selective proteasome inhibitor, the downstream mechanisms of cytotoxicity and drug resistance are poorly understood.

Biosynthetic Pathways for 3-hydroxypropionic Acid Production

Applied Microbiology and Biotechnology. Apr, 2009  |  Pubmed ID: 19221732

Biobased platform chemicals have attracted growing interest recently. Among them, 3-hydroxypropionic acid receives significant attention due to its applications in the synthesis of novel polymer materials and other derivatives. To establish a biotechnology route instead of the problematic chemical synthesis of 3-hydroxypropionic acid, biosynthetic pathway is required, and the strategies of how to engineer a microbe to produce this product should be considered. In the present review, we summarize and review all known pathways, which could be potentially constructed for 3-hydroxypropionic acid production. Mass and redox balances are discussed in detail. Thermodynamic favorability is evaluated by standard Gibbs free energy. The assembly of pathways and possible solutions are proposed. Several new techniques and future research needs are also covered.

A Frequency-controlled Random Mutagenesis Method for GC-rich Genes

Analytical Biochemistry. May, 2009  |  Pubmed ID: 19268416

A novel random mutagenesis strategy was developed by combining sodium bisulfite modification with polymerase chain reaction (PCR). This method introduced the predominant substitution of GC to AT, meaning that it was more suitable for mutagenesis of GC-rich genes and helped to decrease the GC content of target DNA. Mutation efficiency correlated with modification time and different mutation frequency could easily be obtained by controlling modification time. The results indicated that this method could yield a desired and adequate frequency of random mutation to the DNA of interest, especially GC-rich genes, and provided a powerful tool for directed molecular evolution.

Tunicamycin Enhances TRAIL-induced Apoptosis by Inhibition of Cyclin D1 and the Subsequent Downregulation of Survivin

Experimental & Molecular Medicine. May, 2009  |  Pubmed ID: 19307757

TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers.

TNF-related Apoptosis-inducing Ligand Suppresses PRDX4 Expression

FEBS Letters. May, 2009  |  Pubmed ID: 19364504

TNF-related apoptosis-inducing ligand (TRAIL) is currently considered a promising target for developing anti-cancer therapies. Accumulating evidences have now shown that oxidative stress is involved in the TRAIL-mediated cell death. The peroxiredoxins (PRDXs) are a ubiquitous family of proteins involved in protection against oxidative stress through the detoxification of cellular peroxides. Here we demonstrated that endogenous expression of PRDX4 was significantly decreased by TRAIL at the transcriptional level. In addition, overexpression of PRDX4 dramatically suppressed TRAIL-induced apoptosis. Taken together, these data for the first time suggested that TRAIL suppressed the PRDX4 gene at the transcriptional level and that downregulation of PRDX4 might facilitate cell death induced by TRAIL.

Inhibition of the JNK Signalling Pathway Enhances Proteasome Inhibitor-induced Apoptosis of Kidney Cancer Cells by Suppression of BAG3 Expression

British Journal of Pharmacology. Nov, 2009  |  Pubmed ID: 19681889

Proteasome inhibitors represent a novel class of anti-tumour agents that have clinical efficacy against haematological and solid cancers. The anti-apoptotic protein BAG3 is a member of the Bcl-2-associated athanogene family. We have previously shown that BAG3 is up-regulated after exposure to proteasome inhibitors and that inhibition of BAG3 sensitized cells to apoptosis induced by proteasome inhibition. However, the mechanisms by which proteasome inhibition induced BAG3 expression remained unclear and the present experiments were designed to elucidate these mechanisms.

A Staphylococcus Aureus Fitness Test Platform for Mechanism-based Profiling of Antibacterial Compounds

Chemistry & Biology. Aug, 2009  |  Pubmed ID: 19716473

The emergence of drug-resistant bacteria coupled with the limited discovery of novel chemical scaffolds and druggable targets inspires new approaches to antibiotic development. Here we describe a chemical genomics strategy based on 245 Staphylococcus aureus antisense RNA strains, each engineered for reduced expression of target genes essential for S. aureus growth. Attenuation of gene expression can sensitize cells to compounds that inhibit the activity of a gene product or associated process. Pools of strains grown competitively in the presence of bioactive compounds generate characteristic profiles of strain sensitivities reflecting compound mechanism of action. Here, we validate this approach with a structurally and mechanistically diverse set of reference antibiotics and, in the accompanying paper in this issue of Chemistry & Biology (Huber et al., 2009), demonstrate its use in the discovery of new cell wall inhibitors.

Chemical Genetic Identification of Peptidoglycan Inhibitors Potentiating Carbapenem Activity Against Methicillin-resistant Staphylococcus Aureus

Chemistry & Biology. Aug, 2009  |  Pubmed ID: 19716474

Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial and community-acquired pathogen for which few existing antibiotics are efficacious. Here we describe two structurally related synthetic compounds that potentiate beta-lactam activity against MRSA. Genetic studies indicate that these agents target SAV1754 based on the following observations: (i) it has a unique chemical hypersensitivity profile, (ii) overexpression or point mutations are sufficient to confer resistance, and (iii) genetic inactivation phenocopies the potentiating effect of these agents in combination with beta-lactams. Further, we demonstrate these agents inhibit peptidoglycan synthesis. Because SAV1754 is essential for growth and structurally related to the recently reported peptidoglycan flippase of Escherichia coli, we speculate it performs an analogous function in S. aureus. These results suggest that SAV1754 inhibitors might possess therapeutic potential alone, or in combination with beta-lactams to restore MRSA efficacy.

Fast Ion-transfer Processes at Nanoscopic Liquid/liquid Interfaces

Angewandte Chemie (International Ed. in English). 2009  |  Pubmed ID: 19768823

Novel Alkali-stable, Cellulase-free Xylanase from Deep-sea Kocuria Sp. Mn22

Journal of Microbiology and Biotechnology. Sep, 2009  |  Pubmed ID: 19809242

A novel xylanase gene, Kxyn, was cloned from Kocuria sp. Mn22, a bacteria isolated from the deep sea of the east Pacific. Kxyn consists of 1,170 bp and encodes a protein of 390 amino acids that shows the highest identity (63%) with a xylanase from Thermobifida fusca YX. The mature protein with a molecular mass of approximately 40 kDa was expressed in Escherichia coli BL21 (DE3). The recombinant Kxyn displayed its maximum activity at 55 degrees and at pH 8.5. The Km, Vmax, and kcat values of Kxyn for birchwood xylan were 5.4 mg/ml, 272 micromol/min.mg, and 185.1/s, respectively. Kxyn hydrolyzed birchwood xylan to produce xylobiose and xylotriose as the predominant products. The activity of Kxyn was not affected by Ca2+, Mg2+, Na+, K+, beta- mercaptoethanol, DTT, or SDS, but was strongly inhibited by Hg2+, Cu2+, Zn2+, and Pb2+. It was stable over a wide pH range, retaining more than 80% activity after overnight incubation at pH 7.5-12. Kxyn is a cellulase-free xylanase. Therefore, these properties make it a candidate for various industrial applications.

A Novel PH-stable, Bifunctional Xylanase Isolated from a Deep-sea Microorganism, Demequina Sp. JK4

Journal of Microbiology and Biotechnology. Oct, 2009  |  Pubmed ID: 19884762

A genomic library was constructed to clone a xylanase gene (Mxyn10) from Demequina sp. JK4 isolated from a deep sea. Mxyn10 encoded a 471 residue protein with a calculated molecular mass of 49 kDa. This protein showed the highest sequence identity (70%) with the xylanase from Streptomyces lividans. Mxyn10 contains a catalytic domain that belongs to the glycoside hydrolase family 10 (GH10) and a carbohydrate-binding module (CBM) belonging to family 2. The optimum pH and temperature for enzymatic activity were pH 5.5 and 55 degrees C, respectively. Mxyn10 exhibited good pH stability, remaining stable after treatment with buffers ranging from pH 3.5 to 10.0. The protein was not significantly affected by a variety of chemical reagents, including some compounds that usually inhibit the activity of other related enzymes. In addition, Mxyn10 showed activity on cellulose. These properties mark Mxyn10 as a potential enzyme for industrial application and saccharification processes essential for bioethanol production.

Structural Convergence Between Cryo-EM and NMR Reveals Intersubunit Interactions Critical for HIV-1 Capsid Function

Cell. Nov, 2009  |  Pubmed ID: 19914170

Mature HIV-1 particles contain conical-shaped capsids that enclose the viral RNA genome and perform essential functions in the virus life cycle. Previous structural analysis of two- and three-dimensional arrays of the capsid protein (CA) hexamer revealed three interfaces. Here, we present a cryoEM study of a tubular assembly of CA and a high-resolution NMR structure of the CA C-terminal domain (CTD) dimer. In the solution dimer structure, the monomers exhibit different relative orientations compared to previous X-ray structures. The solution structure fits well into the EM density map, suggesting that the dimer interface is retained in the assembled CA. We also identified a CTD-CTD interface at the local three-fold axis in the cryoEM map and confirmed its functional importance by mutagenesis. In the tubular assembly, CA intermolecular interfaces vary slightly, accommodating the asymmetry present in tubes. This provides the necessary plasticity to allow for controlled virus capsid dis/assembly.

Effect of Aspirin on High Glucose-induced Senescence of Endothelial Cells

Chinese Medical Journal. Dec, 2009  |  Pubmed ID: 20137501

Endothelial cell senescence is accelerated under high glucose condition, which may contribute to the vascular complications in the diabetics. It has been proved that aspirin has multiple cytoprotective effects. This study aimed to investigate the effect of aspirin on high glucose-induced endothelial cell senescence and its possible mechanism.

Concerted Modification of Flowering Time and Inflorescence Architecture by Ectopic Expression of TFL1-like Genes in Maize

Plant Physiology. May, 2010  |  Pubmed ID: 20200067

TERMINAL FLOWER1 (TFL1)-like genes are highly conserved in plants and are thought to function in the maintenance of meristem indeterminacy. Recently, we described six maize (Zea mays) TFL1-related genes, named ZEA CENTRORADIALIS1 (ZCN1) to ZCN6. To gain insight into their functions, we generated transgenic maize plants overexpressing their respective cDNAs driven by a constitutive promoter. Overall, ectopic expression of the maize TFL1-like genes produced similar phenotypes, including delayed flowering and altered inflorescence architecture. We observed an apparent relationship between the magnitude of the transgenic phenotypes and the degree of homology between the ZCN proteins. ZCN2, -4, and -5 form a monophylogenetic clade, and their overexpression produced the strongest phenotypes. Along with very late flowering, these transgenic plants produced a "bushy" tassel with increased lateral branching and spikelet density compared with nontransgenic siblings. On the other hand, ZCN1, -3, and -6 produced milder effects. Among them, ZCN1 showed moderate effects on flowering time and tassel morphology, whereas ZCN3 and ZCN6 did not change flowering time but still showed effects on tassel morphology. In situ hybridizations of tissue from nontransgenic plants revealed that the expression of all ZCN genes was associated with vascular bundles, but each gene had a specific spatial and temporal pattern. Expression of four ZCN genes localized to the protoxylem, whereas ZCN5 was expressed in the protophloem. Collectively, our findings suggest that ectopic expression of the TFL1-like genes in maize modifies flowering time and inflorescence architecture through maintenance of the indeterminacy of the vegetative and inflorescence meristems.

Characterization of BAG3 Cleavage During Apoptosis of Pancreatic Cancer Cells

Journal of Cellular Physiology. Jul, 2010  |  Pubmed ID: 20232307

Caspases are a conserved family of cell death proteases that cleave intracellular substrates at Asp residues to modify their function and promote apoptosis. In this report, we identify BAG3 as a novel caspases substrate. Here, we show that one of these BAG proteins, BAG3, is cleaved during apoptosis. BAG3 cleavage is inhibited by several different caspase inhibitors. The analysis of BAG3 cleavage by recombinant caspase proteins shows that BAG3 is efficiently cleaved by caspase-3, to a smaller extent by caspases-1 and -8, and relatively inefficient by caspase-9. Cleavage of the BAG3 protein occurs in the C-terminal part of the protein majorly at Asp347 (KEVD347 downward arrow S) in vitro and in pancreatic cancer SW1990 and PANC-1 cells undergoing apoptosis. We also demonstrate that unlike cleavage of Bcl-2 and Bcl-XL, cleaved form of BAG3 does not result in pro-apoptotic fragments, however, cleavage of BAG3 lead to loss its per se anti-apoptotic property. This novel regulation of BAG3 may have important implications for its role in apoptosis.

Involvement of Oxidative Stress in the Relapse of Acute Myeloid Leukemia

The Journal of Biological Chemistry. May, 2010  |  Pubmed ID: 20233720

The aims of the present study were to determine the level of oxidative stress and the salient factors leading to the relapse of acute myeloid leukemia (AML). Oxidative stress-related parameters and the expressions of specific genes were monitored in 102 cases of AML during a pretreatment period from a primary status to a relapse status. In addition, age-matched healthy subjects were classified as controls. The activities of adenosine deaminase and xanthine oxidase were higher in the relapse condition, whereas those of glutathione peroxidase, monoamine oxidase, and superoxide dismutase, and the total antioxidant capacity (T-AOC) were lower in the primary condition and in controls. Of particular note, levels of advanced oxidation protein products, malondialdehyde, and 8-hydroxydeoxyguanosine were also significantly higher in relapse patients. Furthermore, real-time PCR with SYBR Green revealed that the expression levels of human thioredoxin (TRX) and indoleamine 2,3-dioxygenase were increased in relapse patients. Pearson correlation analysis revealed that the T-AOC was positively correlated with GSH but negatively correlated with 8-OHdG, TRX, and indoleamine 2,3-dioxygenase. Linear regression showed that a low T-AOC and up-regulated TRX expression were the independent factors correlated with relapse. A strong association between oxidative stress and the incidence of disease relapse was observed, which has potential prognosis implications. These results indicate that oxidative stress is a crucial feature of AML and probably affects the development and relapse of AML.

Anti-infectious Activity of Intravitreal Injectable Voriconazole Microspheres on Experimental Rabbit Fungal Endophthalmitis Caused by Aspergillus Fumigatus

Journal of Pharmaceutical Sciences. Nov, 2010  |  Pubmed ID: 21108411

The therapeutic effect of sustained intravitreal injectable voriconazole microspheres (VCZ-MS) on experimental endophthalmitis caused by Aspergillus fumigatus was investigated. VCZ-MS were prepared and evaluated. Vitrectomy was performed on rabbits after intravitreal inoculation of susceptible A. fumigatus. The animals were randomly divided into five groups, including control (no treatment after vitrectomy), vitrectomy plus voriconazole intravitreal injection, and vitrectomy plus intravitreal injection of VCZ-MS containing 0.5, 1.0, or 1.5 mg of voriconazole. The therapeutic effect was assessed at different time intervals. Voriconazole concentrations were monitored in the vitreous injected with VCZ-MS containing 1.0 mg of voriconazole. The results showed that endophthalmitis occurred in all eyes of the control group and rapidly developed into panophthalmitis. The inflammation in the voriconazole and VCZ-MS groups was mild, and in the groups treated with VCZ-MS containing 1.0 or 1.5 mg voriconazole, the inflammation was controlled, the vitreous was clear in all eyes, and there was no recurrence of endophthalmitis. Histopathological examination showed normal structures in the cured eyes, while most uncured eyes were atrophied. Therefore, it can be concluded that an intravitreal injection of VCZ-MS in addition to vitrectomy is an effective treatment for A. fumigatus-induced endophthalmitis in rabbits. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci.

[Preliminarily Screening of Serum Characteristic Markers in Acute Myeloid Leukemia and Clinical Significance]

Zhongguo Shi Yan Xue Ye Xue Za Zhi / Zhongguo Bing Li Sheng Li Xue Hui = Journal of Experimental Hematology / Chinese Association of Pathophysiology. Oct, 2010  |  Pubmed ID: 21129246

This study was purposed to preliminarily screen characteristic tumor markers of acute myeloid leukemia (AML) and to investigate the serum proteomics characteristics of patients with AML and their significance in pathogenesis. 14 patients with AML and 28 healthy controls were enrolled in this study. The serum protein components were captured by weak cation exchange nanometer magnetic beads, the protein mass-spectra of all samples were detected by Autoflex II matrix-assisted laser desorption/ionization time of flight mass spectrometer, and the detection data were analyzed by means of CliprotoolsTM2.2 software, then the differential protein molecules were screened and the diagnostic model was established. Sera of 7 AML patients and 14 healthy controls were selected to verify the established model by using blind test. The results indicated that about 69 protein peaks could be detected within the range of 0.7-10 kD in protein spectra of serum samples from AML patients and controls. Compared with healthy controls, there were 44 statistically differential expression peaks in AML group (p<0.0001). Among them, 10 protein peaks were upregulated protein peaks and 34 protein peaks were downregulated. Diagnostic model was established on the basis of Quick Classifier Algorithm (QC), and the three mass peaks had the strongest power for software to automatically distinguish AML group from control group. Mass charge ratios (m/z) were 3216.57, 4089.7, and 7762.87 respectively. Sensitivity was expected as 86.4% while 82.8% in this established model group. Category validation showed that this diagnostic model correctly identified all 6 cases out of AML and 12 cases out of 14 healthy controls. In cross validation, the model sensitivity and specificity both were 85.7%. It is concluded that the AML QC model is composed of three protein peaks, which can effectively distinguish AML patients from healthy controls. Owing to higher sensitivity and specificity, they may act as serum tumor markers of AML. Among the three proteins, the one with m/z 7762.87 is the platelet-derived protein chemokine (PF4) protein. This finding will probably provide significant experimental evidence for understanding pathogenesis, molecular type, prognosis and treatment effect of AML.

Classification of Transcription Factors Using Protein Primary Structure

Protein and Peptide Letters. Jul, 2010  |  Pubmed ID: 20394581

The transcription factor (TF) is a protein that binds DNA at specific site to help regulate the transcription from DNA to RNA. The mechanism of transcriptional regulatory can be much better understood if the category of transcription factors is known. We introduce a system which can automatically categorize transcription factors using their primary structures. A feature analysis strategy called "mRMR" (Minimum Redundancy, Maximum Relevance) is used to analyze the contribution of the TF properties towards the TF classification. mRMR is coupled with forward feature selection to choose an optimized feature subset for the classification. TF properties are composed of the amino acid composition and the physiochemical characters of the proteins. These properties will generate over a hundred features/parameters. We put all the features/parameters into a classifier, called NNA (nearest neighbor algorithm), for the classification. The classification accuracy is 93.81%, evaluated by a Jackknife test. Feature analysis using mRMR algorithm shows that secondary structure, amino acid composition and hydrophobicity are the most relevant features for classification. A free online classifier is available at http://app3.biosino.org/132dvc/tf/.

Suppression of MG132-mediated Cell Death by Peroxiredoxin 1 Through Influence on ASK1 Activation in Human Thyroid Cancer Cells

Endocrine-related Cancer. Sep, 2010  |  Pubmed ID: 20410161

Proteasome inhibitors represent a novel class of antitumor agents with pre-clinical and clinical evidence of activity against hematologic malignancies and solid tumors. However, emerging evidence indicates that antiapoptotic factors may also accumulate as a consequence of exposure to these drugs, thus it seems plausible that the activation of survival signaling cascades might compromise their antitumoral effects. Peroxiredoxins (PRDXs) are a family of thiol-containing peroxidases identified primarily by their ability to remove cellular hydroperoxides. The function of PRDX1 in particular has been implicated in regulating cell proliferation, differentiation, and apoptosis. Another important finding is that aberrant upregulation of PRDX1 has been discovered in various cancers. Apoptosis signal-regulating kinase 1 (ASK1) is a mitogen-activated protein kinase (MAPK) kinase kinase that is regulated under conditions of cellular stress. ASK1 phosphorylates c-Jun N-terminal kinase and p38 MAPK, and elicits an apoptotic response. ASK1 activity is regulated at multiple levels, one of which is through interaction with PRDX1. In this study, for the first time we report that upregulation of PRDX1 expression was found in thyroid cancer cells treated with proteasome inhibitors, and PRDX1 knockdown resulted in accelerated proteasome inhibitor-induced cell death. In addition, we demonstrated that ASK1 activity was implicated in the PRDX1-dependent response of thyroid cancer cells to proteasome inhibitor-mediated cell death.

Shape "Break-and-Repair" Strategy and Its Application to Computerized Medical Image Segmentation

IEEE Transactions on Visualization and Computer Graphics. Apr, 2010  |  Pubmed ID: 20421678

In three-dimensional medical imaging, the existence of various diseases, image noise or artifacts, and individual anatomical variety generally impose a challenge for accurate segmentation of specific structures. To address these problems, a shape analysis strategy termed "break-and-repair" is presented in this study to facilitate automated medical image segmentation. Similar to surface approximation using a limited number of control points, the basic idea is to remove problematic regions and then estimate a smooth and complete surface shape by representing the remained regions with high fidelity as an implicit function. The innovation of this shape analysis strategy is the capability of solving challenging medical image segmentation problems in a unified framework, regardless of the anatomical variability of anatomical structures in question. The feasibility and performance of this strategy are demonstrated by applying it to automated segmentation of two completely different anatomical structures depicted on CT examinations, namely human lungs and pulmonary nodules. Our quantitative experiments on a large number of clinical CT examinations collected from different sources demonstrate the accuracy, robustness, and generality of the shape "break-and-repair" strategy in medical image segmentation.

A Comparative Study of Fibroid Ablation Rates Using Radio Frequency or High-intensity Focused Ultrasound

Cardiovascular and Interventional Radiology. Aug, 2010  |  Pubmed ID: 20544227

This study compared the technical success of fibroid devascularization using high-intensity focused ultrasound (HIFU) and radio frequency (RF) to provide an experimental basis for the clinical selection of a suitable, minimally invasive method for treating uterine fibroids. Patients were randomly divided into two groups and treated with HIFU or RF accordingly. The two groups of patients were divided again into subgroups A, B, and C based on fibroid diameter and subgroups A', B', and C' based on fibroid blood supply grades. The fibroid diameters in subgroups A, B, and C were 2.0 cm 0.05). In other subgroups, the complete ablation rates of RF were better than those of HIFU (p < 0.05). No severe complications were observed after these two treatments. RF can be applied for the majority of fibroids. As a noninvasive therapy, HIFU could be the preferred method for the treatment of small, hypovascular fibroids.

[Expression and Immunity of Multi-HIV B'/C Subype Genes in Replicating DNA Vaccines]

Bing Du Xue Bao = Chinese Journal of Virology / [bian Ji, Bing Du Xue Bao Bian Ji Wei Yuan Hui]. May, 2010  |  Pubmed ID: 20572342

To understand the effect of various gene structures of HIV B'/C subtype on the gene expression and immunity in DNA vaccine, replicating DNA vector pSCK2 was used to construct seven DNA vaccines carrying one or more of HIV B'/C subtype genes: gagpol, gp160 and rtn (rev, tat and nef fusion gene). Immunofluorescence staining indicated that Gag, Gp160, Rev, Tat and Nef could be expressed from the seven DNA vaccines. Stronger expression was observed with the gene in single-gene expression plasmid or with the gene located at upper-IRES in double- or multi-gene expression plasmid. ELISA test showed that Gag induced higher antibody response, but the antibody titers stimulated by Gp160, Pol, or RTN were very low. Both Gag single-gene expression plasmid and Gag-RTN double-gene expression plasmid separately inoculating induced stronger antibody response against Gag than Gag-Gp160 double-gene expression plasmid and Gagpol-Gp160-RTN multi-gene expression plasmid or combined inoculation of Gag and Gp160 single-gene expression plasmids did. ELISPOT detection showed that all the seven DNA vaccines could stimulate cellular immune response against Gag, Pol, Gp160, Tat, and Nef, respectively. Gagpol or Gp160 single-gene expression plasmid separately inoculating stimulated the strongest cellular immune response. Tat and Nef expressed in all the plasmids induced similar immune response. These results indicated that HIV B'/C subtype genes gagpol, gp160 and rtn could be efficiently expressed in the replicating DNA vaccine vector, single-gene expression plasmid had the higher gene expression level and induced stronger immune response; combined immunization of Gagpol and Gp160 had dramatically lower immunity than Gagpol or Gp160 separated immunization did. Immunity of RTN had no difference between combined and separated immunizations. Therefore, in case of immunization with DNA vaccines containing different HIV genes, it is necessary to optimize the combined immunization procedure, especially for the combination of Gag and Gp160-containing vaccines.

Percutaneous Injection of Hemostatic Agents for Active Liver Hemorrhage

Hepatobiliary & Pancreatic Diseases International : HBPD INT. Aug, 2010  |  Pubmed ID: 20688605

Active hemorrhage arising from hepatic injury can be life-threatening and require immediate attention. At present, nonoperative management of abdominal solid organ injuries has become the usual method of care. The purpose of this study was to determine whether hemocoagulase injection alone guided by contrast-enhanced ultrasonography (CEUS) could control active bleeding in rabbit liver.

Novel Mucoadhesive Polysaccharide Isolated from Bletilla Striata Improves the Intraocular Penetration and Efficacy of Levofloxacin in the Topical Treatment of Experimental Bacterial Keratitis

The Journal of Pharmacy and Pharmacology. Sep, 2010  |  Pubmed ID: 20796194

The objective of the present study was to evaluate a novel mucoadhesive polymer extracted from Bletilla striata for ocular delivery of 0.5% levofloxacin in rabbits, and to determine its improved efficacy against experimental keratitis.

Maize Global Transcriptomics Reveals Pervasive Leaf Diurnal Rhythms but Rhythms in Developing Ears Are Largely Limited to the Core Oscillator

PloS One. 2010  |  Pubmed ID: 20886102

Plant diurnal rhythms are vital environmental adaptations to coordinate internal physiological responses to alternating day-night cycles. A comprehensive view of diurnal biology has been lacking for maize (Zea mays), a major world crop.

[Anti-infectious Activity of Intravitreal Injectable Voriconazole Microspheres on Experimental Rabbit Fungal Endophthalmitis of Aspergillus Fumigatus]

Yao Xue Xue Bao = Acta Pharmaceutica Sinica. Jun, 2010  |  Pubmed ID: 20939190

The therapeutic effect of sustained intravitreal injectable voriconazole microspheres (VCZ-MS) on an experimental endophthalmitis of Aspergillus fumigatus was investigated. VCZ-MS was prepared successfully and its physico-chemical property was also evaluated. Right eyes of albino rabbits were infected with an intravitreal injection of 1 000 CFU x mL(-1) of susceptible Aspergillus fumigatus. All fungal endophthalmitis models were randomly divided into five groups 48 hours later: Group A is control group with no treatment; in group B, vitrectomy was performed combined with intravitreal 3 times injections of 100 microg x 0.1 mL(-1) voriconazole every other day. In group C, D and E, vitrectomy was performed combined with intravitreal injection of 0.5 mg, 1.0 mg and 1.5 mg VCZ-MS respectively. The treatment effect was assessed by slit lamp and indirect ophthalmoscope funduscopy examination, using clinical grading system of inflammation in the anterior chamber and the vitreous opacity. The optical microscopy revealed that microspheres obtained from the experiment design were opaque, discrete and spherical particles with smooth surfaces. The drug content and encapsulation efficiency of microspheres were 29.94% and 73.5%, respectively. Endophthalmitis occurred in all eyes of group A, and rapidly developed to panophthalmitis. The inflammation grade of group B, C, D or E was lower than that of group A (P < 0.05). The grade of vitreous opacity in group C, D, E is lower than group B (P < 0.05). Two eyes in group C developed to panophthalmitis. But in group D and E, all eyes whose inflammation was controlled had no recurrence with vitreous clear. Histopathological examination showed normal structures in the cured eyes, while most uncured eyes were atrophic and with eyeball destroyed. So, it can be safely concluded that the curative effect of intravitreal VCZ-MS is significantly better than that of routine intraocular injection of voriconazole. The optimal dose is the one containing 1.0 mg voriconazole.

Implication of Unfolded Protein Response in Resveratrol-induced Inhibition of K562 Cell Proliferation

Biochemical and Biophysical Research Communications. Jan, 2010  |  Pubmed ID: 19944671

Resveratrol (RES), a natural plant polyphenol, is an effective inducer of cell cycle arrest and apoptosis in a variety of carcinoma cell types. In addition, RES has been reported to inhibit tumorigenesis in several animal models suggesting that it functions as a chemopreventive and anti-tumor agent in vivo. The chemopreventive and chemotherapeutic properties associated with resveratrol offer promise for the design of new chemotherapeutic agents. However, the mechanisms by which RES mediates its effects are not yet fully understood. In this study, we showed that RES caused cell cycle arrest and proliferation inhibition via induction of unfolded protein response (UPR) in human leukemia K562 cell line. Treatment of K562 cells with RES induced a number of signature UPR markers, including transcriptional induction of GRP78 and CHOP, phosphorylation of eukaryotic initiation factor 2alpha (eIF2alpha), ER stress-specific XBP-1 splicing, suggesting the induction of UPR by RES. RES inhibited proliferation of K562 in a concentration-dependent manner. Flow cytometric analyses revealed that K562 cells were arrested in G1 phase upon RES treatment. Salubrinal, an eIF2alpha inhibitor, or overexpression of dominant negative mutants of PERK or eIF2alpha, effectively restored RES-induced cell cycle arrest, underscoring the important role of PERK/eIF2alpha branch of UPR in RES-induced inhibition of cell proliferation.

Enhanced Antitumor Effects of an Engineered Measles Virus Edmonston Strain Expressing the Wild-type N, P, L Genes on Human Renal Cell Carcinoma

Molecular Therapy : the Journal of the American Society of Gene Therapy. Mar, 2010  |  Pubmed ID: 20051938

Measles virus Edmonston strain (MV-Edm) is thought to have remarkable oncolytic activity that selectively destroys human tumor cells. The P/V/C protein of wild-type MV was shown to resist the antiviral effects of interferon (IFN)-alpha. Here, we engineered new MVs by arming MV-Edm tag strain (a V-defective vaccine-lineage strain, MV-Etag) with the P or N, P, and L genes of wild-type MV (MV-P and MV-NPL, respectively). The oncolytic activities of the MVs were determined in human renal cell carcinoma (RCC) cell lines and primary human RCC cells by the MTT assay. The antitumor efficacy of the MVs was evaluated in A-498 xenografts in nude mice. IFN-alpha effectively inhibited the replication of MV-Etag and MV-P, but not MV-NPL. MV-NPL more efficiently induced cytopathic effects (CPEs) in OS-RC-2 cells, even in the presence of human IFN-alpha. MV-NPL replicated more rapidly than MV-P and MV-Etag in A-498 cells. Apoptosis was induced earlier in A-498 cells by MV-NPL than MV-Etag and MV-P. MV-NPL showed more significant antitumoral effects and had prolonged replication compared to MV-Etag and MV-P. In this study, we demonstrated that the newly engineered MV-NPL has more effective oncolytic activity and may help establish an innovative cancer therapy.

Chitosan and Alginate Polyelectrolyte Complex Membranes and Their Properties for Wound Dressing Application

Journal of Materials Science. Materials in Medicine. May, 2010  |  Pubmed ID: 20101440

This study investigated the characteristics and drug release properties of membranes of chitosan and alginate prepared via a casting/solvent evaporation technique. Membranes of chitosan and alginate with silver sulfadiazine as model drug incorporated in different concentrations and different membrane compositions were obtained. The polyblend solution viscosity reached to the highest at the composition polyblends of (1:1). This chitosan/alginate membranes showed pH- and ionic strength-dependent water uptake properties and had the WVTR rang from 442 to 618 g/m(2)/day. The maximum value of the dry membrane of breaking strength was 52.16 MPa and the maximum value of the wet membrane breaking elongation was 46.28%. The results of controlled release studies showed that the silver sulfadiazine release rate was the fastest when the alginate content was 50%. On the basis of the requisite physical properties, the chitosan-alginate PEC membrane can be considered for potential wound dressing or controlled release application.

A Novel Endoglucanase (Cel9P) from a Marine Bacterium Paenibacillus Sp. BME-14

Applied Biochemistry and Biotechnology. Mar, 2010  |  Pubmed ID: 19448979

By constructing a genomic library, an endoglucanase gene (cel9P) was cloned from Paenibacillus sp. BME-14 which was isolated from the sea. It had an open-reading frame of 1,629 bp, encoding a peptide of 542-amino acid residue with a calculated molecular mass of 60 kDa. The enzyme showed the highest amino acid identity of 52% with other known endoglucanases and had a C-terminal catalytic domain belonging to the glycosyl hydrolases family 9. The optimum pH and temperature for enzymatic activity was pH 6.5 and 35 degrees C. The metal ions of Ca(2+), Mg(2+), and Mn(2+) had a positive effect on the activity while Hg(2+), Cu(2+), and EDTA had a negative effect. Notably, Cel9P had 65% of the maximal activity at 5 degrees C. Based on the special characteristic of Cel9P, it had a potential significance for study of cold-active mechanism and industry applications.

The Biological Characteristics and Pharmacodynamics of a Mycophenolate Mofetil Nanosuspension Ophthalmic Delivery System in Rabbits

Journal of Pharmaceutical Sciences. Oct, 2010  |  Pubmed ID: 20973093

The purpose of this study was to investigate corneal mucoadhesion, pharmacokinetics in lacrimal fluid and aqueous humor, the immune suppression induced by corneal transplantation of mycophenolate mofetil (MMF) nanosuspensions (NS), and the use of a chitosan-modified MMF nanosuspension (C-NS) as an ophthalmic delivery system. The results indicated that NS had a higher drug concentration in corneal muscoadhesive samples, lacrimal fluid and aqueous humor samples than the MMF ophthalmic suspension. In addition, C-NS had a much higher concentration than the NS. The mean survival time of cornea in corneal allografts was extended remarkably in the NS and C-NS trial groups. The results confirm that the C-NS and NS markedly increase corneal mucoadhesion and drug absorption, prolong the survival time of high-risk allografts, and significantly inhibit corneal immune rejection in a rabbit model of penetrating keratoplasty. In this model, C-NS was more effective than NS. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci.

Shape "break-and-repair" Strategy and Its Application to Automated Medical Image Segmentation

IEEE Transactions on Visualization and Computer Graphics. Jan, 2011  |  Pubmed ID: 21071791

In three-dimensional medical imaging, segmentation of specific anatomy structure is often a preprocessing step for computer-aided detection/diagnosis (CAD) purposes, and its performance has a significant impact on diagnosis of diseases as well as objective quantitative assessment of therapeutic efficacy. However, the existence of various diseases, image noise or artifacts, and individual anatomical variety generally impose a challenge for accurate segmentation of specific structures. To address these problems, a shape analysis strategy termed "break-and-repair" is presented in this study to facilitate automated medical image segmentation. Similar to surface approximation using a limited number of control points, the basic idea is to remove problematic regions and then estimate a smooth and complete surface shape by representing the remaining regions with high fidelity as an implicit function. The innovation of this shape analysis strategy is the capability of solving challenging medical image segmentation problems in a unified framework, regardless of the variability of anatomical structures in question. In our implementation, principal curvature analysis is used to identify and remove the problematic regions and radial basis function (RBF) based implicit surface fitting is used to achieve a closed (or complete) surface boundary. The feasibility and performance of this strategy are demonstrated by applying it to automated segmentation of two completely different anatomical structures depicted on CT examinations, namely human lungs and pulmonary nodules. Our quantitative experiments on a large number of clinical CT examinations collected from different sources demonstrate the accuracy, robustness, and generality of the shape "break-and-repair" strategy in medical image segmentation.

An Intramolecular Salt Bridge Drives the Soluble Domain of GTP-bound Atlastin into the Postfusion Conformation

The Journal of Cell Biology. Nov, 2011  |  Pubmed ID: 22065636

Endoplasmic reticulum (ER) network branching requires homotypic tethering and fusion of tubules mediated by the atlastin (ATL) guanosine triphosphatase (GTPase). Recent structural studies on the ATL soluble domain reveal two dimeric conformers proposed to correspond to a tethered prefusion state and a postfusion state. How the prefusion conformer transitions to the postfusion conformer is unknown. In this paper, we identify an intramolecular salt bridge mediated by two residues outside the GTPase domain near the point of rotation that converts the prefusion dimer to the postfusion state. Charge reversal of either residue blocked ER network branching, whereas a compensatory charge reversal to reestablish electrostatic attraction restored function. In vitro assays using the soluble domain revealed that the salt bridge was dispensable for GTP binding and hydrolysis but was required for forming the postfusion dimer. Unexpectedly, the postfusion conformation of the soluble domain was achieved when bound to the nonhydrolyzable GTP analogue guanosine 5'-[β,γ-imido]triphosphate, suggesting that nucleotide hydrolysis might not be required for the prefusion to postfusion conformational change.

Direct Visualization of HIV-1 with Correlative Live-cell Microscopy and Cryo-electron Tomography

Structure (London, England : 1993). Nov, 2011  |  Pubmed ID: 22078557

Cryo-electron tomography (cryoET) allows 3D visualization of cellular structures at molecular resolution in a close-to-native state and therefore has the potential to help elucidate early events of HIV-1 infection in host cells. However, structural details of infecting HIV-1 have not been observed, due to technological challenges in working with rare and dynamic HIV-1 particles in human cells. Here, we report structural analysis of HIV-1 and host-cell interactions by means of a correlative high-speed 3D live-cell-imaging and cryoET method. Using this method, we showed under near-native conditions that intact hyperstable mutant HIV-1 cores are released into the cytoplasm of host cells. We further obtained direct evidence to suggest that a hyperstable mutant capsid, E45A, showed delayed capsid disassembly compared to the wild-type capsid. Together, these results demonstrate the advantages of our correlative live-cell and cryoET approach for imaging dynamic processes, such as viral infection.

Fabrication of SiO2@ZrO2@Y2O3:Eu3+ Core-multi-shell Structured Phosphor

Journal of Nanoscience and Nanotechnology. Aug, 2011  |  Pubmed ID: 22103106

ZrO2 interface was designed to block the reaction between SiO2 and Y2O3 in SiO2@Y2O3:Eu coreshell structure phosphor. SiO2@ZrO2@Y2O3:Eu core-multi-shell phosphors were successfully synthesized by combing an LBL method with a Sol-gel process. Based on electron microscopy, X-ray diffraction, and spectroscopy experiments, compelling evidence for the formation of the Y2O3:Eu outer shell on ZrO2 were presented. The presence of ZrO2 layer on SiO2 core can block the reaction of SiO2 core and Y2O3 shell effectively. By this kind of structure, the reaction temperature of the SiO2 core and Y2O3 shell in the SiO2@Y2O3:Eu core-shell structure phosphor can be increased about 200-300 degrees C and the luminescent intensity of this structure phosphor can be improved obviously. Under the excitation of ultraviolet (254 nm), the Eu3+ ion mainly shows its characteristic red (611 nm, 5D0-7F2) emissions in the core-multi-shell particles from Y2O3:Eu3+ shells. The emission intensity of Eu3+ ions can be tuned by the annealing temperatures, the number of coating times, and the thickness of ZrO2 interface, respectively.

Increasing Fatty Acid Production in E. Coli by Simulating the Lipid Accumulation of Oleaginous Microorganisms

Journal of Industrial Microbiology & Biotechnology. Aug, 2011  |  Pubmed ID: 20972897

Unlike many oleaginous microorganisms, E. coli only maintains a small amount of natural lipids in cells, impeding its utility to overproduce fatty acids. In this study, acetyl-CoA carboxylase (ACC) from Acinetobacter calcoaceticus was expressed in E. coli to redirect the carbon flux to the generation of malonyl-CoA, which resulted in a threefold increase in intracellular lipids. Moreover, providing a high level of NADPH by overexpressing malic enzyme and adding malate to the culture medium resulted in a fourfold increase in intracellular lipids (about 197.74 mg/g). Co-expression of ACC and malic enzyme resulted in 284.56 mg/g intracellular lipids, a 5.6-fold increase compared to the wild-type strain. This study provides some attractive strategies for increasing lipid production in E. coli by simulating the lipid accumulation of oleaginous microorganisms, which could aid the development of a prokaryotic fatty acid producer.

TNF-α Induces Early Growth Response Gene-1 Expression Via ERK1/2 Activation in Endothelial Cells

Acta Diabetologica. Jan, 2011  |  Pubmed ID: 21212994

TNF-α and hyperglycemia are important factors contributing to vascular complications in obese and diabetic patients. The present studies aimed to examine, in endothelial cells, downstream signaling mechanisms that may ultimately link TNF-α and hyperglycemia to vascular pathology. Human umbilical vein endothelial cells were cultured and incubated with 10 ng/ml TNF-α and/or 25 mmol/l glucose. The expression of early growth response gene-1 (Egr-1) and ERK1/2 protein was quantified by Western blotting, and plasminogen activator inhibitor-1 (PAI-1) levels were measured by ELISA. Both glucose and TNF-α increased Egr-1 expression, while simultaneous exposure to the two factors exerted an additive effect. Furthermore, PAI-1 was also upregulated in the presence of TNF-α and glucose. The MEK inhibitor, PD98059, downregulated TNF-α-induced Egr-1 expression. TNF-α (10 ng/ml) increased ERK1/2 levels 1.76 ± 0.23-fold (P < 0.01) after 25 mmol/l glucose pretreatment, but added glucose did not enhance ERK1/2 activation when given subsequent to TNF-α treatment. TNF-α induced Egr-1 protein expression and PAI-1 levels through the ERK1/2 pathway. Differential regulation of Egr-1 expression by glucose and TNF-α in endothelial cells may be an important consideration in the mechanisms linking these factors to the development of vascular dysfunction in metabolic disorders such as diabetes.

Quantitative Assessment of MLAA-34 Expression in Diagnosis and Prognosis of Acute Monocytic Leukemia

Cancer Immunology, Immunotherapy : CII. Apr, 2011  |  Pubmed ID: 21240483

MLAA-34 is a newly identified monocytic leukemia-associated antigen. Previous data indicated that MLAA-34 might be a novel anti-apoptosis factor related closely to carcinogenesis or progression of acute monocytic leukemia. The over-expression of MLAA-34 is intuitively expected to be associated with unfavorable clinical features in acute myeloid leukemia. However, there have been no clinical studies about the prognostic relevance of MLAA-34 expression in human malignancies. This study was done to investigate the clinical relevance of the expression of MLAA-34 in de novo acute myeloid leukemia. In 126 patients with de novo acute myeloid leukemia, the level of MLAA-34 expression and protein expression ratio were determined by using quantitative reverse transcriptase-PCR and western blot, respectively. The results were analyzed with respect to the patients' clinical features and treatment outcomes. Both MLAA-34 expression rates and expression levels were found to be higher in patients with the French-American-British classification subtype M5, and the expression levels were also higher in patients with a leukocyte number of ≥ 20 × 10(9)/L and patients with extramedullary disease. In addition, MLAA-34 over-expression (≥ median expression) was associated with an unfavorable day 7 response to induction chemotherapy and also associated with a poor survival rate. In multivariate analysis, high MLAA-34 levels was independently associated with a poorer relapse-free survival and overall survival in AML patients. In conclusion, our data indicate that MLAA-34 may be used as a prognostic marker for treatment decision-making in acute monocytic leukemia through validation by further studies.

HIV Fragment Gag Vaccine Induces Broader T Cell Response in Mice

Vaccine. Mar, 2011  |  Pubmed ID: 21292005

Broad T-cell response is considered critical for HIV-1 vaccines to compensate viral diversity. Usually, a limited number of immunodominant epitopes are recognized in natural infections, as well as in vaccinations. Here, we seek to overcome immunofocusing of CD8 T Cell responses to HIV-1 CN54 gag DNA (delivered as a plasmid) in BalB/C mice by splitting it into fragments for reducing competition of recognition between dominant and sub-dominant epitopes. As expected, mice immunized with mixture of DNA fragments elicited significantly broader T cell responses than whole-length gag. We also further studied the effects when fragments and full-length DNA vaccines are combined for prime-boost vaccination. Interestingly, mice primed with full-length gag and boosted with DNA vaccine fragments induced similar T-cell response breadth as mice both primed and boosted by fragments DNA. In contrast, mice primed with DNA vaccine fragments and boosted with full-length gag failed to broaden T cell responses, once again, only the dominant epitopes were recognized. In summary, our study demonstrated that "fragmentation strategy" can indeed broaden T cell responses. This enhancement is more likely achieved in boosting stage. This study offers a promising way to design a vaccine with higher chance covering the highly diversified circulating strains.

Proteasome Inhibition Induces a P38 MAPK Pathway-dependent Antiapoptotic Program Via Nrf2 in Thyroid Cancer Cells

The Journal of Clinical Endocrinology and Metabolism. May, 2011  |  Pubmed ID: 21346076

Our previous data showed that reactive oxygen species generation might be ascribed to the cytotoxic response of thyroid cancer cells to proteasome inhibition and the ability of cancer cells to induce catalytic subunit for glutamate cysteine ligase (GCLC) and subsequent production of glutathione, thereby scavenging reactive oxygen species was partly ascribed to the cytotoxic responses of thyroid cancer cells to proteasome inhibition. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor responsible for transcriptional activation of various cytoprotective genes including GCLC.

Anti-infectious Activity of Intravitreal Injectable Voriconazole Microspheres on Experimental Rabbit Fungal Endophthalmitis Caused by Aspergillus Fumigatus

Journal of Pharmaceutical Sciences. May, 2011  |  Pubmed ID: 21374612

The therapeutic effect of sustained intravitreal injectable voriconazole microspheres (VCZ-MS) on experimental endophthalmitis caused by Aspergillus fumigatus was investigated. VCZ-MS were prepared and evaluated. Vitrectomy was performed on rabbits after intravitreal inoculation of susceptible A. fumigatus. The animals were randomly divided into five groups, including control (no treatment after vitrectomy), vitrectomy plus voriconazole intravitreal injection, and vitrectomy plus intravitreal injection of VCZ-MS containing 0.5, 1.0, or 1.5 mg of voriconazole. The therapeutic effect was assessed at different time intervals. Voriconazole concentrations were monitored in the vitreous injected with VCZ-MS containing 1.0 mg of voriconazole. The results showed that endophthalmitis occurred in all eyes of the control group and rapidly developed into panophthalmitis. The inflammation in the voriconazole and VCZ-MS groups was mild, and in the groups treated with VCZ-MS containing 1.0 or 1.5 mg voriconazole, the inflammation was controlled, the vitreous was clear in all eyes, and there was no recurrence of endophthalmitis. Histopathological examination showed normal structures in the cured eyes, while most uncured eyes were atrophied. Therefore, it can be concluded that an intravitreal injection of VCZ-MS in addition to vitrectomy is an effective treatment for A. fumigatus-induced endophthalmitis in rabbits.

The FT-like ZCN8 Gene Functions As a Floral Activator and Is Involved in Photoperiod Sensitivity in Maize

The Plant Cell. Mar, 2011  |  Pubmed ID: 21441432

The mobile floral-promoting signal, florigen, is thought to consist of, in part, the FT protein named after the Arabidopsis thaliana gene FLOWERING LOCUS T. FT is transcribed and translated in leaves and its protein moves via the phloem to the shoot apical meristem where it promotes the transition from vegetative to reproductive development. In our search for a maize FT-like floral activator(s), seven Zea mays CENTRORADIALIS (ZCN) genes encoding FT homologous proteins were studied. ZCN8 stood out as the only ZCN having the requisite characteristics for possessing florigenic activity. In photoperiod sensitive tropical lines, ZCN8 transcripts were strongly upregulated in a diurnal manner under floral-inductive short days. In day-neutral temperate lines, ZCN8 mRNA level was independent of daylength and displayed only a weak cycling pattern. ZCN8 is normally expressed in leaf phloem, but ectopic expression of ZCN8 in vegetative stage shoot apices induced early flowering in transgenic plants. Silencing of ZCN8 by artificial microRNA resulted in late flowering. ZCN8 was placed downstream of indeterminate1 and upstream of delayed flowering1, two other floral activator genes. We propose a flowering model linking photoperiod sensitivity of tropical maize to diurnal regulation of ZCN8.

[Peptide Mapping of H-2d Restricted T-cell Epitope Against Six Antigens of HIV-1 Subtype B'/C by ELISPOT Assay]

Bing Du Xue Bao = Chinese Journal of Virology / [bian Ji, Bing Du Xue Bao Bian Ji Wei Yuan Hui]. Jan, 2011  |  Pubmed ID: 21462504

The purpose is to screen and identify the specific H-2d restricted T-cell epitopes. These epitopes are used to investigate the cellular immune response of BALB/c (H-2d) mice immunized with a HIV-1 vaccine which expresses six antigens of gp160, gag, pol, rev, tat and nef of HIV subtype B'/C. A replicating DNA vaccine and a non-replicating recombinant vaccinia virus vector, both expressing the six antigens mentioned above, were used to immune BALB/c (H-2d) mice in a prime-boost regiment. The six peptide libraries of HIV B'/C corresponding respectively to the six complete antigens were pooled according to a designed matrix format and used to test for IFN-gamma production from splenocytes of immunized mice by an enzyme-linked immunospot (IFN-gamma ELISPOT) assay. The ELISPOT data indicated that two of seven Gag-specific T-cell epitope peptides were identified to be the novel epitopes. One of three Pol-specific T-cell epitope is unreported. One novel epitope was confirmed in two gp160-specific T-cell epitope peptides. One Nef-specific T-cell epitope was identified. Three Tat-specific T-cell epitope peptides were continuous sequences in Tat peptide library and all contained either complete or partial sequence reported. Rev-specific T-cell epitope was not be found. The specific T-cell epitopes (H-2d restricted) were identified by IFN-7 ELISPOT assay, which could be used to detect the cellular immune response of BALB/c mice immunized with the HIV-1 vaccine expressing six antigens of gp160, gag, pol, rev, tat and nef of HIV subtype B'/C.

[The Non-replicating Recombinant Vaccinia Virus Expressing Six Genes of HIV-1 Can Be Passaged Stably in CEF]

Bing Du Xue Bao = Chinese Journal of Virology / [bian Ji, Bing Du Xue Bao Bian Ji Wei Yuan Hui]. Mar, 2011  |  Pubmed ID: 21528538

To investigate the genetic stability (including the vector of vaccinia virus and six foreign genes: gp160, gag, pol, rev, tat and nef) of the HIV-1 non-replicating recombinant vaccinia virus (rNTV-C). rNTV-C was serially passaged to passage 25 (P25) in primary chicken embryo fibroblast (CEF). P9, P12, P15 and P25 were selected to study the genetic stability in four aspects, including the genetic stability of viral vector, the genetic stability of six foreign genes, the expressing stability of foreign genes and the genetic loss of foreign genes. The results showed that the viral vector was non-replicated vaccinia virus of Tiantan strain and was passaged stably; foreign gene sequences matched with designed sequences, the insert sites were right, and the nucleotide mutation rate was less than one over ten thousands within different passages of rNTV-C; the target proteins could be expressed effectively, and the expression level was stable within different passages of rNTV-C; the genetic loss of gag and nef was less than 5% within different passages of rNTV-C. The above results provided important data for the vaccine production.

Visual Effects of Haptic Feedback Are Large but Local

PloS One. 2011  |  Pubmed ID: 21572964

Vision generally provides reliable predictions for touch and motor-control, but some classes of stimuli evoke visual illusions. Using haptic feedback on virtual 3-D surfaces, we tested the function of touch in such cases. Our experiments show that in the perception of 3-D shapes from texture cues, haptic information can dominate vision in some cases, changing percepts qualitatively from convex to concave and concave to slant. The effects take time to develop, do not outlive the cessation of the feedback, are attenuated by distance, and drastically reduced by gaps in the surface. These dynamic shifts in qualitative perceived shapes could be invaluable in neural investigations that test whether haptic feedback modifies selective activation of neurons or changes the shape-tuning of neurons responsible for percepts of 3-D shapes.

Sensitivity Gains in Chemosensing by Optical and Structural Modulation of Ordered Assembly Arrays of ZnO Nanorods

ACS Nano. Jun, 2011  |  Pubmed ID: 21604766

Nanomaterials and -structures have attracted much attention owing to their applications to ultrasensitive nanodevices. In this work, ordered assembly arrays of ZnO nanorods have been hydrothermally fabricated and used as optical substrates of fluorescence sensors for toxic vapors. The unique fastigiate nanorod assembly combines merits of single fibers and clusters, possessing identical orientation, large surface-to-volume ratio, evanescent transmission, and evanescent coupling. As coated on the assembly arrays, different sensing materials all generated amplified spontaneous emission (ASE) action such that the fluorescence intensity of the narrowed spectrum was 52.4-fold enhanced. Results of sensing experiments indicate that sensors based on the assembly arrays displayed 100% elevated normalized quenching rate and several times longer full-load time compared with reference sensors. This work provides a facile method to fabricate secondary structures of 1D rigid material and presents a new way to design highly sensitive optic sensors. Furthermore, evanescent excitation caused ASE action of fluorescent organics, and the correlative sensitivity gain is of interest in both theoretical research and the applications field.

Glucosamine Induces Cell Death Via Proteasome Inhibition in Human ALVA41 Prostate Cancer Cell

Experimental & Molecular Medicine. Sep, 2011  |  Pubmed ID: 21697645

Glucosamine, a naturally occurring amino monosaccharide, has been reported to play a role in the regulation of apoptosis more than half century. However the effect of glucosamine on tumor cells and the involved molecular mechanisms have not been thoroughly investigated. Glucosamine enters the hexosamine biosynthetic pathway (HBP) downstream of the rate-limiting step catalyzed by the GFAT (glutamine:fluctose- 6-phosphate amidotransferase), providing UDPGlcNAc substrates for O-linked β-N-acetylglucosamine (O-GlcNAc) protein modification. Considering that O-GlcNAc modification of proteasome subunits inhibits its activity, we examined whether glucosamine induces growth inhibition via affecting proteasomal activity. In the present study, we found glucosamine inhibited proteasomal activity and the proliferation of ALVA41 prostate cancer cells. The inhibition of proteasomal activity results in the accumulation of ubiquitinated proteins, followed by induction of apoptosis. In addition, we demonstrated that glucosamine downregulated proteasome activator PA28γ and overexpression of PA28γ rescued the proteasomal activity and growth inhibition mediated by glucosamine. We further demonstrated that inhibition of O-GlcNAc abrogated PA28γ suppression induced by glucosamine. These findings suggest that glucosamine may inhibit growth of ALVA41 cancer cells through downregulation of PA28γ and inhibition of proteasomal activity via O-GlcNAc modification.

Beyond Flowering Time: Pleiotropic Function of the Maize Flowering Hormone Florigen

Plant Signaling & Behavior. Sep, 2011  |  Pubmed ID: 21847027

The transition from vegetative to reproductive development is a critical turning point in a plant’s life cycle. It is now widely accepted that a leaf-borne signal, florigen, moves via the phloem from leaves to the shoot apical meristem to trigger its reprogramming to produce flowers. In part, the florigenic signal comprises a protein that belongs to the phosphatidylethanolamine-binding protein (PEBP) family that is present in all living organisms but displays diverse functions. The founding floral-promoting PEBP gene in Arabidopsis is FLOWERING LOCUS T (FT) whose functional homologs have been indentified in many flowering plants. We recently accumulated sufficient evidence to demonstrate the maize FT homolog ZCN8 has florigenic function. This task was particularly challenging due to the large number of FT-homologous genes in the maize genome. Here we show that ZCN8 function is more complex than simply regulating the floral transition. ZCN8 appears to play a pleiotropic role in the regulation of generalized growth of vegetative and reproductive tissues.

Involvement of JNK and NF-κB Pathways in Lipopolysaccharide (LPS)-induced BAG3 Expression in Human Monocytic Cells

Experimental Cell Research. Jan, 2012  |  Pubmed ID: 22020323

Lipopolysaccharide (LPS) is an outer-membrane glycolipid component of Gram-negative bacteria known for its fervent ability to activate monocytic cells and for its potent proinflammatory capabilities. Bcl-2-associated athanogene 3 (BAG3) is a survival protein that has been shown to be stimulated during cell response to stressful conditions, such as exposure to high temperature, heavy metals, proteasome inhibition, and human immunodeficiency virus 1 (HIV-1) infection. In addition, BAG3 regulates replication of Varicella-Zoster Virus (VZV) and Herpes Simplex Virus (HSV) replication, suggesting that BAG3 could participate in the host response to infection. In the current study, we found that LPS increased the expression of BAG3 in a dose- and time-dependent manner. Actinomycin D completely blocked the LPS-induced BAG3 accumulation, as well as LPS activated the proximal promoter of BAG3 gene, supported that the induction by LPS occurred at the level of gene transcription. LPS-induced BAG3 expression was blocked by JNK or NF-κB inhibition, suggesting that JNK and NF-κB pathways participated in BAG3 induction by LPS. In addition, we also found that induction of BAG3 was implicated in monocytic cell adhesion to extracellular matrix induced by LPS. Overall, the data support that BAG3 is induced by LPS via JNK and NF-κB-dependent signals, and involved in monocytic cell-extracellular matrix interaction, suggesting that BAG3 may have a role in the host response to LPS stimulation.

Sex Difference of the Prevalence and Risk Factors Associated with Prehypertension Among Urban Chinese Adults from 33 Communities of China: the CHPSNE Study

Journal of Hypertension. Mar, 2012  |  Pubmed ID: 22241140

: As a new category of blood pressure (BP) classification according to the Seventh Report of The Joint National Committee, prehypertension has aroused people's great concern in recent years due to its associations with increased incidence of cardiovascular disease. However, there is little information about the epidemiology of prehypertension in urban China. The aim of this study is to estimate the prevalence of prehypertension and to identify its risk factors among urban Chinese men and women.

Epidemiology of Prehypertension and Associated Risk Factors in Urban Adults From 33 Communities in China

Circulation Journal : Official Journal of the Japanese Circulation Society. Feb, 2012  |  Pubmed ID: 22293448

Background: The Seventh Report of The Joint National Committee has recently introduced the prehypertension category of blood pressure (BP) status that needs monitoring and intervention. Little is known about the epidemiology of prehypertension in urban China, so this study aimed at estimating the prevalence of prehypertension and identifying risk factors in urban Chinese adults. Methods and Results: Using a multistage cluster and random sampling method, a representative sample of 25,196 urban adults aged 18-74 years in northeast of China was selected from 2009 to 2010. The survey of BP and associated risk factors was carried out in 33 communities. Multiple logistic regression methods were used to identify risk factors for prehypertension. Overall, 40.5% of urban Chinese adults had prehypertension, with a prevalence of 47.7% and 33.6% in men and women, respectively. Multivariate logistic regression analysis revealed the risk factors of being overweight (adjusted odds ratio [aOR]=1.38, 95% confidence interval [CI]: 1.26-1.52), obesity (aOR=3.94, 95%CI: 2.99-5.20), central obesity (aOR=2.13, 95%CI: 1.96-2.32). Being female, and having a higher education level, higher family income and diet control were protective factors. Conclusions: Prehypertension is common among urban residents in China, and is associated with many risk factors. Comprehensive lifestyle modifications need to be taken to decrease the incidence of prehypertension and to prevent prehypertension progressing to hypertension and cardiovascular disease.