This study aimed to investigate the effectiveness and safety of lower doses of mifepristone combined with misoprostol for the termination of ultra-early pregnancy. A total of 2500 women with ultra-early pregnancy (amenorrhea ? 35 days) were randomly divided into 5 groups with gradually decreased dose of oral mifepristone from 150 to 50 mg followed by 200 µg of oral misoprostol 24 hours later. The primary end point was complete abortion without surgical intervention. Secondary end points were vaginal bleeding, return of menses, and side effects. Rates of complete abortion were high in all groups. Moreover, the lower doses of mifepristone led to shorter vaginal bleeding period, the return of menses on the expected date, and fewer side effects. Lower doses of mifepristone combined with 200 µg of misoprostol are as effective and safe as higher doses of this combination for the termination of ultra-early pregnancy with lower possibility of vaginal bleeding and side effects.
Long non-coding RNAs have been reported to play an important role in cellular metabolism and development. Homeobox transcript antisense intergenic RNA (HOTAIR), a long non-coding RNA, is pervasively over-expressed in most human cancers compared with non-cancerous adjacent tissues. Although many articles have reported that HOTAIR is closely associated with metastasis, epithelial-mesenchymal transition, advanced pathological stage, drug resistance, and poor prognosis, the role of HOTAIR in gene regulation and tumor development is largely unknown, and the potential molecular mechanisms are not complete clear yet. In this review, we summarized the recent progress in the study of the major functions of HOTAIR. miR-331-3p, miR-130a, miR-7, miR-141, HER2, c-MYC, WIF-1, RBM38, PTEN, and Col-1 are involved in the HOTAIR regulation network. We tried to elucidate the molecular mechanisms of HOTAIR in the aspects of tumorigenesis, metastasis, drug resistance, and regulation.
Endogenous (circadian) and exogenous (e.g. diel) biological rhythms are a prominent feature of many living systems. In green algal species, knowledge of the extent of diel rhythmicity of genome wide gene expression, its evolution, and its cis-regulatory mechanism is limited. In this study, we identified cyclically expressed genes under diel conditions in Chlamydomonas reinhardtii and found that ~50% of the 17,114 annotated genes exhibited cyclic expression. These cyclic expression patterns indicate a clear succession of biological processes during the course of a day. Among 237 functional categories enriched in cyclically expressed genes, >90% were phase-specific, including photosynthesis, cell division and motility related processes. By contrasting cyclic expression between C. reinhardtii and Arabidopsis thaliana putative orthologs, we found significant but weak conservation in cyclic gene expression patterns. On the other hand, within C. reinhardtii cyclic expression was preferentially maintained between duplicates and the evolution of phase between paralogs is limited to relatively minor time shifts. Finally, to better understand the cis regulatory basis of diel expression, putative cis-regulatory elements were identified that could predict the expression phase of a subset of the cyclic transcriptome. Our findings demonstrate both the prevalence of cycling genes as well as the complex regulatory circuitry required to control cyclic expression in a green algal model, highlighting the need to consider diel expression in studying algal molecular networks and in future biotechnological applications.
Efficient bacterial recombinational DNA repair involves rapid cycles of RecA filament assembly and disassembly. The RecX protein plays a crucial inhibitory role in RecA filament formation and stability. As the broken ends of DNA are tethered during homologous search, RecA filaments assembled at the ends are likely subject to force. In this work, we investigated the interplay between RecX and force on RecA filament formation and stability. Using magnetic tweezers, at single molecular level, we found that Mycobacterium tuberculosis (Mt) RecX could catalyze stepwise de-polymerization of preformed MtRecA filament in the presence of ATP hydrolysis at low forces (<7 pN). However, applying larger forces antagonized the inhibitory effects of MtRecX, and a partially de-polymerized MtRecA filament could re-polymerize in the presence of MtRecX, which cannot be explained by previous models. Theoretical analysis of force-dependent conformational free energies of naked ssDNA and RecA nucleoprotein filament suggests that mechanical force stabilizes RecA filament, which provides a possible mechanism for the observation. As the antagonizing effect of force on the inhibitory function of RecX takes place in a physiological range; these findings broadly suggest a potential mechanosensitive regulation during homologous recombination.
Na(+)-K(+)-2Cl(-) co-transporter isoform 1 (NKCC1) mRNA and protein decrease with increasing age in the cochlear lateral wall of C57BL/6J (C57) mice. The down-regulation of NKCC1 may influence the K(+) transport efficiency and the homeostasis of ion transport cells, and cause the irreversible damage of cochlear cells in old C57 mice. Our results indicate that NKCC1 may play an important role in the pathogenesis of age-related hearing loss (AHL).
Although regional lymph nodes (RLN) dissection remains the only way to cure pancreatic cancer metastasis, it is unavoidably associated with sizable trauma, multiple complications, and low surgical resection rates. Thus, exploring a treatment approach for the ablation of drug-resistant pancreatic cancer is always of great concern. Moreover, reoperative and intraoperative mapping of RLN is also important during treatment, because only a few lymph nodes can be detected by the naked eye. In our study, graphene oxides modified with iron oxide nanoparticles (GO-IONP) as a nanotheranostic agent is firstly developed to diagnose and treat RLN metastasis of pancreatic cancer. The approach was designed based on clinical practice, the GO-IONP agent directly injected into the tumor was transported to RLN via lymphatic vessels. Compared to commercial carbon nanoparticles currently used in the clinic operation, the GO-IONP showed powerful ability of dual-modality mapping of regional lymphatic system by magnetic resonance imaging (MRI), as well as dark color of the agent providing valuable information that was instrumental for surgeon in making the preoperative plan before operation and intraoperatively distinguish RLN from surrounding tissue. Under the guidance of dual-modality mapping, we further demonstrated that metastatic lymph nodes including abdominal nodes could be effectively ablated by near-infrared (NIR) irradiation with an incision operation. The lower systematic toxicity of GO-IONP and satisfying safety of photothermal therapy (PTT) to neighbor tissues have also been clearly illustrated in our animal experiments. Using GO-IONP as a nanotheranostic agent presents an approach for mapping and photothermal ablation of RLN, the later may serve as an alternative to lymph node dissection by invasive surgery.
Hypermethylation of promoter CpG islands represents an alternative mechanism to inactivate tumor suppressor genes. This study was to detect promoter methylation status and mRNA expression levels of ARRDC3, ELP3, GATA5, and PAX6, and to explore the association between methylation and expression in invasive ductal carcinomas (IDCs) and matched normal tissues (MNTs) from breast cancer patients. Aberrant gene methylation was observed as follows: ARRDC3 in 38.5 %, ELP3 in 73.1 %, GATA5 in 48.1 %, and PAX6 in 50.0 % of IDCs. mRNA expression of ARRDC3, ELP3, and GATA5 in IDCs showed a lower level than that in MNTs (P < 0.001, P = 0.001 and P < 0.001, respectively). For ARRDC3, both methylated and unmethylated IDCs showed significantly lower expression values compared to MNTs (P = 0.001 and P = 0.007, respectively). For ELP3 and GATA5, methylated tumors only showed significantly lower expression values compared to MNTs (P = 0.001 and P < 0.001, respectively). For ARRDC3 and GATA5, methylation was associated with their less fold change in IDCs (P = 0.049 and P = 0.020, respectively). Methylation of ARRDC3 was significantly associated with grades and lymph node status of IDCs (P = 0.036 and P = 0.002, respectively). Methylation frequency of ELP3 was higher in lymph node positive versus lymph node negative tumors (P = 0.020); whereas methylation frequency of PAX6 was lower in tumors with the ER negative samples (P = 0.025). Our data suggested that promoter hypermethylation may be an important mechanism of the transcriptional inactivation of ARRDC3, GATA5, and ELP3 in IDCs.
The signal recognition particle (SRP) directs translating ribosome-nascent chain complexes (RNCs) that display a signal sequence to protein translocation channels in target membranes. All previous work on the initial step of the targeting reaction, when SRP binds to RNCs, used stalled and non-translating RNCs. This meant that an important dimension of the co-translational process remained unstudied. We apply single-molecule fluorescence measurements to observe directly and in real-time E. coli SRP binding to actively translating RNCs. We show at physiologically relevant SRP concentrations that SRP-RNC association and dissociation rates depend on nascent chain length and the exposure of a functional signal sequence outside the ribosome. Our results resolve a long-standing question: how can a limited, sub-stoichiometric pool of cellular SRP effectively distinguish RNCs displaying a signal sequence from those that are not? The answer is strikingly simple: as originally proposed, SRP only stably engages translating RNCs exposing a functional signal sequence.
A field experiment was conducted to study the effects of all-day warming on the growth, development and yield of winter wheat cultivars bred in different periods under free air temperature increase (FATI) in Xuzhou and Danyang, Jiangsu Province. Warming decreased the effective tillers by 5.2% and 9.6%, and the ineffective tillers by 15.6% and 9.7% in Xuzhou and Danyang, respectively. Plant height under FATI was higher in Xuzhou, but lower in Danyang than that of the control. Plant heights of the late cultivars were lower than that of the early cultivars. Warming increased the leaf area index for all cultivars. Warming increased the net photosynthetic rates of the winter wheat cultivars except for those bred in 1950-1960s and 1980s in Xuzhou and 1950-1960s and 1990s in Danyang. There were different changing tendencies of the night respiration rate among the winter wheat cultivars bred in different periods. Aboveground biomass and harvest index of all cultivars increased under FATI. Harvest index of late cultivars was higher than that of early cultivars in Xuzhou and Danyang. Growth period of different cultivars under FATI was all shortened, av- eragely by 3.2 and 4.1 d in Xuzhou and Danyang, respectively, mainly due to shortening the preheading stage (averagely by 7.5 and 8.5 d in Xuzhou and Danyang, respectively) and prolonging the filling stage (by average 4.3 d). Except for 1950-1960s cultivars in Xuzhou, the grain yields increased under FATI, averagely by 21.0% and 14.1% in Xuzhou and Danyang, respectively. Statistical analysis of variance showed that the warming-induced wheat yield changes were due to the changes in grain number per spike and effective spikes in Xuzhou and the change in 1000-grain mass in Danyang, respectively.
Tissue inhibitor of metalloproteinase-3 (TIMP-3) is an important natural inhibitor of matrix metalloproteinases (MMPs) and of a disintegrin and metalloproteinase with thrombospondin motif (ADAMTs), which can cleave cartilage extracellular matrix components to cause cartilage degradation. In this study, our data suggest TGF-?1 induces TIMP-3 expression through activations of both the ERK1/2 and Smad2/3 signaling pathways. TGF-?1-stimulated TIMP-3 expression was significantly inhibited by SB525334 (TGF-? receptor I kinase inhibitor), accompanied by a reduction in ERK1/2 and Smad3 phosphorylation. We used PD98059 (MEK inhibitor) and SIS3 (inhibitor of Smad3 phosphorylation) to investigate the respective roles of ERK1/2 and Smad2/3 signaling pathways in TGF-?1-induced TIMP-3 expression. The results show PD98059 treatment significantly suppressed TGF-?1-induced ERK1/2 phosphorylation and TIMP-3 expression. Under these conditions, the degree of Smad3 phosphorylation correlated with ERK1/2 activation, which suggests that ERK1/2 may activate Smad3 phosphorylation. SIS3 significantly inhibited TGF-?1-induced Smad3 phosphorylation and TIMP-3 expression. ERK1/2 phosphorylation alone had no effect on TGF-?1-induced TIMP-3 expression, which suggests ERK1/2 via Smad3 phosphorylation regulates TGF-?1-induced TIMP-3 expression. Here, we demonstrate that ERK1/2 may be capable of activating the Smad2/3 signaling pathway to result in TGF-?1-induced TIMP-3 up-regulation.
Statins protect mesenchymal stem cells (MSCs) against the harsh microenvironment and improve the efficacy of MSC transplantation after acute myocardial infarction (AMI); however, the mechanism remains uncertain. Furthermore, the transdifferentiation potential of MSCs in the post-infarct heart remains highly controversial. The RhoA/Rho-associated coiled-coil-forming kinase (ROCK) pathway participates in many aspects of the damaged heart after AMI and related to the "pleiotropic" effects of statins. This study aimed to explore whether atorvastatin (ATV) facilitates the survival and therapeutic efficacy of MSCs via the inhibition of RhoA/ROCK pathway and subsequently its downstream molecular extracellular regulated protein kinase (ERK1/2), and to investigate the transdifferentiation potential of MSCs in vivo.
Species sensitivity distributions (SSDs) methods in both forward and reverse modes were used to evaluate the ecological risk and determine the contaminant concentration threshold for the protection of aquatic species and ecological quality. In this study, the existing toxicity data of freshwater organisms were fitted to SSD functions to estimate the hazardous concentrations for 5% of the species (HC5) for microcystins, ammonia and nitrite, and the ecological risk of their mixtures. The potentially affected fractions (PAFs) of various concentrations of microcystins, ammonia and nitrite were also calculated. Results showed that microcystins exhibited a higher ecological risk than ammonia and nitrite. The HC5 value for microcystins exposure was 19.22 microg x L(-1) whereas the HC5 values for ammonia and nitrite exposure were 6583.94 microg x L(-1) and 334.33 microg x L(-1), respectively. The sensitivity of freshwater organisms varied with exposed concentrations of microcystins, ammonia and nitrite. Crustaceans were more sensitive than fishes to microcystins, and less sensitive than fishes to nitrite when the concentrations of microcystins and nitrite were below 125.04 microg x L(-1) and 2989.40 microg x L(-1), respectively, and vice versa when exposed to higher concentrations of microcystins and nitrite. No significant difference was observed for the sensitivities of fishes and crustaceans exposed to ammonia. In studies with selected lakes in China, our results showed that the ecological risk in both Tai and Hongfeng lakes exceeded the permissible HC5 threshold, and the multiple substance potentially affected fractions (msPAFs) of microcystins, ammonia and nitrite were 2.6%-5.6%, indicating that the ecological risk of their mixtures was more threatening than each individual contaminant being investigated.
miRNA-218 is a highlighted tumor suppressor and its underlying role in tumor progression is still unknown. Here, we restored the expression of miRNA-218 in pancreatic cancer to clarify the function and potent downstream pathway of miRNA-218. The expressions of both miRNA-218 and its potent target gene ROBO1 were revealed by RT-PCR and western blotting analysis. Transfection of miRNA-218 precursor mimics and luciferase assay were performed to elucidate the regulation mechanism between miRNA-218 and ROBO1. Cells, stably expressing miRNA-218 followed by forced expression of mutant ROBO1, were established through co-transfections of both lentivirus vector and plasmid vector. The cell migration and invasion abilities were evaluated by migration assay and invasion assay respectively. An increased expression of ROBO1 was revealed in cell BxPC-3-LN compared with cell BxPC-3. Elevated expression of miRNA-218 would suppress the expression of ROBO1 via complementary binding to a specific region within 3'UTR of ROBO1 mRNA (sites 971-978) in pancreatic cancer cells. Stably restoring the expression of miRNA-218 in pancreatic cancer significantly downregulated the expression of ROBO1 and effectively inhibited cell migration and invasion. Forced expression of mutant ROBO1 could reverse the repression effects of miRNA-218 on cell migration and invasion. Consequently, miRNA-218 acted as a tumor suppressor in pancreatic cancer by inhibiting cell invasion and migration. ROBO1 was a functional target of miRNA-218's downstream pathway involving in cell invasion and migration of pancreatic cancer.
Co-treatment of neuroprotective reagents may improve the therapeutic efficacy of hypothermia in protecting neurons during ischemic stroke. This study aimed to find promising drugs that enhance the neuroprotective effect of mild hypothermia (MH). 26 candidate drugs were selected based on different targets. Primary cultured cortical neurons were exposed to oxygen-glucose deprivation and reoxygenation (OGD/R) to induce neuronal damage, followed by either single treatment (a drug or MH) or a combination of a drug and MH. Results showed that, compared with single treatment, combination of MH with brain derived neurotrophic factor, glibenclamide, dizocilpine, human urinary kallidinogenase or neuroglobin displayed higher proportion of neuronal cell viability. The latter three drugs also caused less apoptosis rate in combined treatment. Furthermore, co-treatment of those three drugs and MH decreased the level of reactive oxygen species (ROS) and intracellular calcium accumulation, as well as stabilized mitochondrial membrane potential (MMP), indicating the combined neuroprotective effects are probably via inhibiting mitochondrial apoptosis pathway. Taken together, the study suggests that combined treatment with hypothermia and certain neuroprotective reagents provide a better protection against OGD/R-induced neuronal injury.
HER2-amplified (HER2 + ) breast cancers are treated with the anti-HER2 monoclonal antibody trastuzumab. Although trastuzumab reduces production of the angiogenic factor VEGF in HER2 + tumors, the acute and sustained effects of trastuzumab on the tumor vasculature are not understood fully, particularly in trastuzumab-resistant tumors. We used mouse models of trastuzumab sensitive and trastuzumab-resistant HER2 + breast cancers to measure dynamic changes in tumor microvessel density and hemoglobin oxygenation (sO2) in vivo using quantitative hyperspectral imaging at 2, 5, 9, and 14 days after antibody treatment. Further analysis quantified the distribution of microvessels into low and high oxygenation groups, and monitored changes in these distributions with trastuzumab treatment. Gold standard immunohistochemistry was performed to validate complementary markers of tumor cell and vascular response to treatment. Trastuzumab treatment in both responsive and resistant tumors resulted in decreased sO2 5 days after initial treatment when compared to IgG-treated controls (p<0.05). Importantly, responsive tumors showed significantly higher vessel density and significantly lower sO2 than all other groups at 5 days post-treatment (p<0.05). Distribution analysis of vessel sO2 showed a significant (p<0.05) shift of highly oxygenated vessels towards lower oxygenation over the time-course in both trastuzumab-treated responsive and resistant tumors. This study suggests that longitudinal hyperspectral imaging of microvessel sO2 and density could distinguish trastuzumab-responsive from trastuzumab-resistant tumors, a finding that could be exploited in the post-neoadjuvant setting to guide post-surgical treatment decisions.
Protein nanoassemblies possess unique advantage in biomedical applications such as drug delivery, biocatalysis and vaccine development. Despite recent accomplishment in atomic structure data, the underlying molecular mechanism of protein self-assembly remains elusive, where considerable heterogeneity is often involved. Here we use E. coli chaperonin GroEL, a tetradecameric protein with a molecular weight of 805 kDa, to probe its transformation from cage-like oligomers to protein nanofibers. We show that sodium dodecyl sulfate (SDS), a widely-used protein denaturant, at submicellar concentration binds to and causes partial distortion of GroEL apical domain. Subsequently, the GroEL apical domain with altered secondary structural content converts the GroEL oligomers into modular structural units which are observed to self-assemble into cylindrical nanofibers under an agitated incubation in a physiological buffer. Interestingly, through targeted mutagenesis where two cysteine residues are introduced at the entry site of GroEL cage, we found that the formation of GroEL nanoassembly could be modulated depending on the redox condition of incubation. Without the need of chemical engineering, tunable GroEL nanofibers built by controlled-assembly are among the largest nanoscale bioassembly with broad applications.
To investigate the effects of sodium selenite against aflatoxin B1 (AFB 1), 200 male Avian broilers, divided into five groups, were fed with basal diet (control group), 0.3?mg/kg AFB1 (AFB1 group), 0.3?mg/kg AFB1?+?0.2?mg/kg Se (+Se group I), 0.3?mg/kg AFB1?+?0.4?mg/kg Se (+Se group II) and 0.3?mg/kg AFB1?+?0.6?mg/kg Se (+Se group III), respectively. Compared with the control group, decreased relative weight of bursa of Fabricius and contents of serum immunoglobulin, more vacuoles and debris in the bursal lymphoid follicle, and increased percentage of apoptotic bursal cells were observed in the AFB1 group. Sodium selenite, however, could increase the relative weight of bursa of Fabricius and contents of serum immunoglobulin, and ameliorate histopathological lesions. The percentages of apoptotic bursal cells, through flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method, in the three +Se groups were lower than those in the AFB 1 group. Compared with the AFB 1 group, moreover, the mRNA expressions of Bax and Caspase-3 by qRT-PCR in the three +Se groups were decreased, while the expression of Bcl-2 was increased. The results indicate that sodium selenite in diet can protect chicken from AFB 1-induced impairment of humoral immune function by reducing bursal histopathological lesions and percentages of apoptotic bursal cells.
A fluorescence chemsensor for carbon monoxide (CO), based on transformation of weakly fluorescent iodide to strong fluorescent amino product upon reacting with CO, shows abilities of quantitative measurement of CO in air at a level of 50-1000 ppm and real-time and on-site monitoring for CO flammation/explosion.
The aim of the present study was to evaluate the association between DNA methylation and multidrug resistance (MDR) in glioma and identify novel effectors responsible for MDR in human gliomas. An MDR glioma cell line, SGH?44/ADM, was developed using adriamycin (ADM) impulse treatment. Cryopreservation, recovery and withdrawal were performed to evaluate the stability of SGH?44/ADM cells. The adherence rate and cellular morphology were observed by microscopy, and the cell growth curve and doubling time were determined. DNA methylation was analyzed using a methylated DNA immunoprecipitation microarray chip (MeDIP?Chip). The cell cycle, Rh123 ingestion and exudation, and SGH?44/ADM apoptosis were analyzed by flow cytometry. SGH?44/ADM cells showed little difference as compared with parental cells, except that SGH?44/ADM cells were bigger in size with a wizened nucleus. Compared to SGH?44 cells, a larger proportion of SGH?44/ADM cells remained in G1 and S phase, as measured by flow cytometry. The MDR of SGH?44/ADM was associated with the upregulation of multi?drug resistance 1, prostaglandin?endoperoxide synthase 2 (COX?2); protein kinase C ? (PKC?); however, the expression of these genes was not associated with DNA methylation. In the MeDIP?Chip analysis, 74 functions were markedly enhanced, and seven significant pathways were observed. Genes including SNAP47, ARRB2, PARD6B, TGFB1, VPS4B and CBLB were identified by gene ontology analysis. The predominant molecular mechanism of MDR in SGH?44/ADM cells was identified as exocytosis and efflux. The expression of COX?2, PKC? and P?glycoprotein (Pgp) was not found to be associated with DNA methylation. Genes including SNAP47, VAMP4 and VAMP3 may serve as the downstream effectors of Pgp, COX?2 or PKC?; however, further experiments are required to verify these observations.
Cellular membranes act as signaling platforms and control solute transport. Membrane receptors, transporters, and enzymes communicate with intracellular processes through protein-protein interactions. Using a split-ubiquitin yeast two-hybrid screen that covers a test-space of 6.4 × 10(6) pairs, we identified 12,102 membrane/signaling protein interactions from Arabidopsis. Besides confirmation of expected interactions such as heterotrimeric G protein subunit interactions and aquaporin oligomerization, >99% of the interactions were previously unknown. Interactions were confirmed at a rate of 32% in orthogonal in planta split-green flourescent protein interaction assays, which was statistically indistinguishable from the confirmation rate for known interactions collected from literature (38%). Regulatory associations in membrane protein trafficking, turnover, and phosphorylation include regulation of potassium channel activity through abscisic acid signaling, transporter activity by a WNK kinase, and a brassinolide receptor kinase by trafficking-related proteins. These examples underscore the utility of the membrane/signaling protein interaction network for gene discovery and hypothesis generation in plants and other organisms.
Eph receptor tyrosine kinases (RTKs) and their ligands, ephrins, play critical roles in development, tissue homeostasis, and cancer. Because Eph receptors are expressed in most adult stem cell niches and in many types of cancers, it has been long suspected that this family of RTKs may also regulate the function of cancer stem-like cells (CSCs). This review will focus on recent studies to elucidate the contribution of Eph/ephrin molecules in CSC self-renewal and tumorigenicity, as well as describe efforts to target these molecules in cancer. Because CSCs are often resistant to therapeutic intervention and have been shown to depend on Eph RTKs for self-renewal, targeting Eph receptors may hold promise for the treatment of drug-resistant cancers.
Using persimmon tannin fraction (PT40), epicatechin-3-gallate-(4beta-->8, 2beta-->O-->7)-epicatechin-3-gallate (A-type ECG dimer) and epigallocatechin-3-gallate (EGCG) as representatives of polyphenols and Chinese cobra snake venom phospholipase A2 (PLA2) as a model protein, different mathematical equations were compared to correct the inner filter effects produced by the fluorescence quenching of those polyphenols to PLA2 based on the gradient, linearity and intercept of Stern-Volmer regression equation. The results revealed that correction by the equation developed by Gauthier et al made a significant reduction in gradients. Besides, the linearity was clearly improved and the intercepts were closer to 1 after correction in all cases. The binding constant of PT40 and PLA2 declined by 60% and the inferred interaction forces were more convinced after correction by the above equation. Therefore, the equation developed by Gauthier et al was the most appropriate equation for correcting the inner filter effects when studying the interaction of polyphenols and protein using fluorescence quenching method.
The observed decline of spring dust storms in Northeast Asia since the 1950s has been attributed to surface wind stilling. However, spring vegetation growth could also restrain dust storms through accumulating aboveground biomass and increasing surface roughness. To investigate the impacts of vegetation spring growth on dust storms, we examine the relationships between recorded spring dust storm outbreaks and satellite-derived vegetation green-up date in Inner Mongolia, Northern China from 1982 to 2008. We find a significant dampening effect of advanced vegetation growth on spring dust storms (r = 0.49, p = 0.01), with a one-day earlier green-up date corresponding to a decrease in annual spring dust storm outbreaks by 3%. Moreover, the higher correlation (r = 0.55, p < 0.01) between green-up date and dust storm outbreak ratio (the ratio of dust storm outbreaks to times of strong wind events) indicates that such effect is independent of changes in surface wind. Spatially, a negative correlation is detected between areas with advanced green-up dates and regional annual spring dust storms (r = -0.49, p = 0.01). This new insight is valuable for understanding dust storms dynamics under the changing climate. Our findings suggest that dust storms in Inner Mongolia will be further mitigated by the projected earlier vegetation green-up in the warming world.
This study aimed to identify aberrant transcripts of the new splice-site mutation c.3244-2A>C in the Wilson disease (WD) gene (ATPase, Cu++ transporting, beta polypeptide, ATP7B) and discuss its genotype and clinical phenotype. DNA and RNA were extracted from peripheral blood lymphocytes, amplified by polymerase chain reaction (PCR) and nested reverse transcription PCR (RT-nested PCR) to characterize the aberrant transcripts. RT-nested PCR product sequencing comparison showed that c.3244-2A>C splice-site mutation caused aberrant transcripts and formatted a new splice acceptor. Patient carrying the splice-site mutation c.3244-2A>C presented early onset age, severe clinical manifestations, and poor prognosis. WD patients with the splice-site mutation show severe clinical manifestations, indicating that aberrant transcripts have important implications for WD phenotype.
A meta-analysis comparing the efficacy and acceptability of selective serotonin reuptake inhibitors (SSRIs) versus tricyclic antidepressants (TCAs) in depressed children, adolescents, and young adults was performed.
Two single nucleotide polymorphisms in Leukotriene A4 hydrolase (LTA4H) gene were reported to be associated with protection from pulmonary tuberculosis in Vietnamese population. But these associations were not found in the Russians. To investigate the association of LTA4H polymorphisms with tuberculosis in a Han Chinese population in Eastern China, we genotyped 5 SNPs of LTA4H gene in 743 of pulmonary tuberculosis patients, 372 of extra-pulmonary tuberculosis patients and 888 of healthy controls individuals. The CC and TT homozygotes of rs1978331and rs2540474 were identified to have higher rates (P < 0.01) and be risk factors in the patients with extra-pulmonary tuberculosis (OR = 1.412; 95% CI = 1.104-1.804 and(OR = 1.380; 95% CI = 1.080-1.764). However, no significant association was found between any of the SNPs and pulmonary tuberculosis. In the extra-pulmonary tuberculosis subgroups. LTA4H gene were significantly associated with tuberculous meningitis, lymph node tuberculosis, bone tuberculosis and other extra-pulmonary tuberculosis except for pleural tuberculosis. The present findings suggest that polymorphisms in the LTA4H gene may affect susceptibility to extra-pulmonary tuberculosis and change the risk of developing the disease in the Han nationality in the East China.
: In contrast to cardiomyocytes, autophagy in cardiac microvascular endothelial cells (CMECs) during ischemia/reperfusion (I/R) injury has not been fully investigated. Tongxinluo (TXL), a traditional Chinese medicine, was shown to be vascular protective. We aimed to elucidate the role of autophagy and its regulatory mechanisms by TXL in CMECs subjected to I/R injury. CMECs were exposed to different treatments for 30 minutes and subjected to hypoxia/reoxygenation each for 2 hours. The results indicated that hypoxia/reoxygenation significantly induced autophagy, as identified by an increased number of monodansylcadaverine-positive CMECs, increased autophagosome formation, and a higher type II/type I of light chain 3 ratio, but not Beclin-1 expression. Autophagy inhibition using 3-methyladenine was proapoptotic, but rapamycin-induced autophagy was antiapoptotic. TXL enhanced autophagy and decreased apoptosis in a dose-dependent manner, reaching its largest effect at 800 ?g/mL. 3-methyladenine attenuated the TXL-promoted autophagy and antiapoptotic effects, whereas rapamycin had no additional effects compared with TXL alone. TXL upregulated mitogen-activated protein kinase and extracellular signal-regulated kinase (ERK) phosphorylation; however, PD98059 abrogated ERK phosphorylation and decreased autophagy and increased apoptosis compared with TXL alone. These results suggest that autophagy is a protective mechanism in CMECs subjected to I/R injury and that TXL can promote autophagy through activation of the mitogen-activated protein kinase/ERK pathway.
The survival ratio of implanted mesenchymal stem cells (MSCs) in the infarcted myocardium is low. Autophagy is a complex "self-eating" process and can be utilized for cell survival. We have found that atorvastatin (ATV) can effectively activate autophagy to enhance MSCs survival during hypoxia and serum deprivation (H/SD). The mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK/ERK) pathway is a non-canonical autophagy pathway. We hypothesized that the MEK/ERK pathway mediated ATV-induced autophagy of MSCs under H/SD.
In the last decade, the overexpression of hepatoma upregulated protein (HURP) has been reported in hepatocellular carcinoma, adrenocortical tumors and urogenital carcinoma. However, the role of HURP in breast cancer remains unknown. In the present study, a comprehensive analysis was performed to examine the HURP expression level in 43 breast cancer tumor samples and paired adjacent normal tissues. The correlation between the HURP expression level and the clinicopathological characteristics was evaluated. The role of HURP in breast cancer was investigated by quantitative polymerase chain reaction, western blot analysis and cell proliferation assays. HURP expression was found to be significantly increased in the breast cancer samples. The HURP expression level was higher in the tumors with advanced-grade metastasis and was strongly associated with tumor-node-metastasis staging (P=0.003). Transfection and cell proliferation assays suggested that the suppression of HURP expression or the interference in HURP activity in the breast cancer cells inhibited cell proliferation significantly. These data suggest that HURP is associated with the degree of malignancy and the proliferation of breast cancer. HURP could be a tumor biomarker for prognosis and a potential therapeutic drug target for human breast cancer.
Lycium barbarum polysaccharide (LBP) was modified by HNO3-Na2SeO3 method according to L9(3(4)) orthogonal design to obtain nine selenizing LBPs (sLBPs), sLBP1-sLBP9. Their antioxidant activities in vitro were compared by free radical-scavenging test. sLBP6, sLBP8 and sLBP9 presented stronger activity. In vivo test, 14-day-old chickens were injected respectively with sLBP6, sLBP8 and sLBP9 taking LBP as control, and serum GSH-Px and SOD activities and MDA content were determined. The results showed that three sLBPs could significantly enhance GSH-Px and SOD activities and decrease MDA content. The actions of sLBPs were significantly stronger than that of unmodified LBP. These results indicated that selenylation modification could significantly enhance the antioxidant activities of LBP, sLBP6 possessed the best efficacy and could be exploited into an antioxidant. The optimal modification conditions were 400mg of sodium selenite for 500 mg of LBP, reaction temperature of 70 °C and reaction time of 6h.
Spontaneous changes in the reading frame of translation are rare (frequency of 10(-3) to 10(-4) per codon), but can be induced by specific features in the messenger RNA (mRNA). In the presence of mRNA secondary structures, a heptanucleotide 'slippery sequence' usually defined by the motif X XXY YYZ, and (in some prokaryotic cases) mRNA sequences that base pair with the 3' end of the 16S ribosomal rRNA (internal Shine-Dalgarno sequences), there is an increased probability that a specific programmed change of frame occurs, wherein the ribosome shifts one nucleotide backwards into an overlapping reading frame (-1 frame) and continues by translating a new sequence of amino acids. Despite extensive biochemical and genetic studies, there is no clear mechanistic description for frameshifting. Here we apply single-molecule fluorescence to track the compositional and conformational dynamics of individual ribosomes at each codon during translation of a frameshift-inducing mRNA from the dnaX gene in Escherichia coli. Ribosomes that frameshift into the -1 frame are characterized by a tenfold longer pause in elongation compared to non-frameshifted ribosomes, which translate through unperturbed. During the pause, interactions of the ribosome with the mRNA stimulatory elements uncouple EF-G catalysed translocation from normal ribosomal subunit reverse-rotation, leaving the ribosome in a non-canonical intersubunit rotated state with an exposed codon in the aminoacyl-tRNA site (A site). tRNA(Lys) sampling and accommodation to the empty A site and EF-G action either leads to the slippage of the tRNAs into the -1 frame or maintains the ribosome into the 0 frame. Our results provide a general mechanistic and conformational framework for -1 frameshifting, highlighting multiple kinetic branchpoints during elongation.
Pancreatic cancer is one of the most common gastrointestinal tumors, with its incidence staying at a high level in both the United States and China. However, the overall 5-year survival rate of pancreatic cancer is still extremely low. Surgery remains the only potential chance for long-term survival. Early diagnosis and precise staging are crucial to make proper clinical decision for surgery candidates. Despite advances in diagnostic technology such as computed tomography (CT) and endoscopic ultrasound, diagnosis, staging and monitoring of the metabolic response remain a challenge for this devastating disease. Positron emission tomography/CT (PET/CT), a relatively novel modality, combines metabolic detection with anatomic information. It has been widely used in oncology and achieves good results in breast cancer, lung cancer and lymphoma. Its utilization in pancreatic cancer has also been widely accepted. However, the value of PET/CT in pancreatic disease is still controversial. Will PET/CT change the treatment strategy for potential surgery candidates? What kind of patients benefits most from this exam? In this review, we focus on the utility of PET/CT in diagnosis, staging, and assessment of resectability of pancreatic cancer. In addition, its ability to monitor metabolic response and recurrence after treatment will be emphasis of discussion. We hope to provide answers to the questions above, which clinicians care most about.
SecM is an E. coli secretion monitor capable of stalling translation on the prokaryotic ribosome without cofactors. Biochemical and structural studies have demonstrated that the SecM nascent chain interacts with the 50S subunit exit tunnel to inhibit peptide bond formation. However, the timescales and pathways of stalling on an mRNA remain undefined. To provide a dynamic mechanism for stalling, we directly tracked the dynamics of elongation on ribosomes translating the SecM stall sequence (FSTPVWISQAQGIRAGP) using single-molecule fluorescence techniques. Within 1 min, three peptide-ribosome interactions work cooperatively over the last five codons of the SecM sequence, leading to severely impaired elongation rates beginning from the terminal proline and lasting four codons. Our results suggest that stalling is tightly linked to the dynamics of elongation and underscore the roles that the exit tunnel and nascent chain play in controlling fundamental steps in translation.
The traditional view of macrolide antibiotics as plugs inside the ribosomal nascent peptide exit tunnel (NPET) has lately been challenged in favor of a more complex, heterogeneous mechanism, where drug-peptide interactions determine the fate of a translating ribosome. To investigate these highly dynamic processes, we applied single-molecule tracking of elongating ribosomes during inhibition of elongation by erythromycin of several nascent chains, including ErmCL and H-NS, which were shown to be, respectively, sensitive and resistant to erythromycin. Peptide sequence-specific changes were observed in translation elongation dynamics in the presence of a macrolide-obstructed NPET. Elongation rates were not severely inhibited in general by the presence of the drug; instead, stalls or pauses were observed as abrupt events. The dynamic pathways of nascent-chain-dependent elongation pausing in the presence of macrolides determine the fate of the translating ribosome stalling or readthrough.
With the development of imaging technology and surgical techniques, pancreatic resections to treat pancreatic tumors, ampulla tumors, and other pancreatic diseases have increased. Pancreaticoduodenectomy, one type of pancreatic resection, is a complex surgery with the loss of pancreatic integrity and various anastomoses. Complications after pancreaticoduodenectomy such as pancreatic fistulas and anastomosis leakage are common and significantly associated with patient outcomes. Pancreatic fistula is one of the most important postoperative complications; this condition can cause intraperitoneal hemorrhage, septic shock, or even death. An effective way has not yet been found to avoid the occurrence of pancreatic fistula. In most medical centers, the frequency of pancreatic fistula has remained between 9% and 13%. The early detection and routine drainage of anastomotic fistulas, pancreatic fistulas, bleeding, or other intra-abdominal fluid collections after pancreatic resections are considered as important and effective ways to reduce postoperative complications and the mortality rate. However, many recent studies have argued that routine drainage after abdominal operations, including pancreaticoduodenectomies, does not affect the incidence of postoperative complications. Although inserting drains after pancreatic resections continues to be a routine procedure, its necessity remains controversial. This article reviews studies of the advantages and disadvantages of routine drainage after pancreaticoduodenectomy and discusses the necessity of this procedure.
New P2Y12 inhibitors can be classified as oral (prasugrel and ticagrelor) and intravenous drugs (cangrelor and elinogrel). These P2Y12 inhibitors might be superior to clopidogrel for reducing ischemic events in patients with coronary artery disease (CAD). We performed a meta-analysis of randomized trials that compared new oral or intravenous P2Y12 inhibitors with clopidogrel to determine their efficacy and safety in patients.
CD148 is a transmembrane tyrosine phosphatase that is expressed at cell junctions. Recent studies have shown that CD148 associates with the cadherin/catenin complex and p120 catenin (p120) may serve as a substrate. However, the role of CD148 in cadherin cell-cell adhesion remains unknown. Therefore, here we addressed this issue using a series of stable cells and cell-based assays. Wild-type (WT) and catalytically inactive (CS) CD148 were introduced to A431D (lacking classical cadherins), A431D/E-cadherin WT (expressing wild-type E-cadherin), and A431D/E-cadherin 764AAA (expressing p120-uncoupled E-cadherin mutant) cells. The effects of CD148 in cadherin adhesion were assessed by Ca2+ switch and cell aggregation assays. Phosphorylation of E-cadherin/catenin complex and Rho family GTPase activities were also examined. Although CD148 introduction did not alter the expression levels and complex formation of E-cadherin, p120, and ?-catenin, CD148 WT, but not CS, promoted cadherin contacts and strengthened cell-cell adhesion in A431D/E-cadherin WT cells. This effect was accompanied by an increase in Rac1, but not RhoA and Cdc42, activity and largely diminished by Rac1 inhibition. Further, we demonstrate that CD148 reduces the tyrosine phosphorylation of p120 and ?-catenin; causes the dephosphorylation of Y529 suppressive tyrosine residue in Src, a well-known CD148 site, increasing Src activity and enhancing the phosphorylation of Y228 (a Src kinase site) in p120, in E-cadherin contacts. Consistent with these findings, CD148 dephosphorylated both p120 and ?-catenin in vitro. The shRNA-mediated CD148 knockdown in A431 cells showed opposite effects. CD148 showed no effects in A431D and A431D/E-cadherin 764AAA cells. In aggregate, these findings provide the first evidence that CD148 promotes E-cadherin adhesion by regulating Rac1 activity concomitant with modulation of p120, ?-catenin, and Src tyrosine phosphorylation. This effect requires E-cadherin and p120 association.
Zero-mode waveguides provide a powerful technology for studying single-molecule real-time dynamics of biological systems at physiological ligand concentrations. We customized a commercial zero-mode waveguide-based DNA sequencer for use as a versatile instrument for single-molecule fluorescence detection and showed that the system provides long fluorophore lifetimes with good signal to noise and low spectral cross-talk. We then used a ribosomal translation assay to show real-time fluidic delivery during data acquisition, showing it is possible to follow the conformation and composition of thousands of single biomolecules simultaneously through four spectral channels. This instrument allows high-throughput multiplexed dynamics of single-molecule biological processes over long timescales. The instrumentation presented here has broad applications to single-molecule studies of biological systems and is easily accessible to the biophysical community.
Spinal muscular atrophy (SMA) is a common and fatal autosomal recessive disorder. Approximately 94% of SMA patients are caused by homozygous deletion of SMN1 gene. SMA carrier screening is recommended considering the high carrier frequency (1 in 35-50) as well as severity of the disease.
Autoantibodies specific to the angiotensin II type I receptor (anti-AT1-AR) have been implicated in the pathology of congestive heart failure (CHF). Anti-AT1-AR may be associated with left ventricular function in CHF patients treated with perindopril.
To investigate the influence of pregnancy on the production of reactive oxygen species (ROS) from mouse peripheral blood neutrophils (PMN), the levels of NO and cytokines from serum, the activation of T lymphocytes, and initially find the immune regulation effects of pregnancy on the mouse peripheral blood lymphocytes.
The purpose of the present study was to investigate the oxidative damage and apoptosis induced by aflatoxin B1 (AFB1) in spleen of broilers. A total of 200 one-day-old avian male broilers were randomly divided into 4 equal groups of 50 each and were fed for 21 days as follows: a control diet and three AFB1 diets containing 0.15, 0.3, and 0.6 mg AFB1/kg diet. Consumption of AFB1 diets induced oxidative stress in the spleen of chicken as evidenced by reduced glutathione peroxidase, glutathione reductase, and catalase activities, decreased glutathione contents, and increased malondialdehyde contents in explaining the pathogenesis. Flow cytometer method and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling assay revealed that the apoptotic splenocytes were increased in AFB1 groups. The results suggest that AFB1 induced excessive apoptosis of splenic lymphocytes, which is correlated with increased oxidative stress. The present results may be helpful for explaining the pathogenesis of AFB1-induced immunosuppression.
Eph receptors and their membrane-bound ligands, the ephrins, represent a complex subfamily of receptor tyrosine kinases (RTKs). Eph/ephrin binding can lead to various and opposite cellular behaviors such as adhesion versus repulsion, or cell migration versus cell-adhesion. Recently, Eph endocytosis has been identified as one of the critical steps responsible for such diversity. Eph receptors, as many RTKs, are rapidly endocytosed following ligand-mediated activation and traffic through endocytic compartments prior to degradation. However, it is becoming obvious that endocytosis controls signaling in many different manners. Here we showed that activated EphA2 are degraded in the lysosomes and that about 35% of internalized receptors are recycled back to the plasma membrane. Our study is also the first to demonstrate that EphA2 retains the capacity to signal in endosomes. In particular, activated EphA2 interacted with the Rho family GEF Tiam1 in endosomes. This association led to Tiam1 activation, which in turn increased Rac1 activity and facilitated Eph/ephrin endocytosis. Disrupting Tiam1 function with RNA interference impaired both ephrinA1-dependent Rac1 activation and ephrinA1-induced EphA2 endocytosis. In summary, our findings shed new light on the regulation of EphA2 endocytosis, intracellular trafficking and signal termination and establish Tiam1 as an important modulator of EphA2 signaling.
Levels of low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, triglycerides and total cholesterol are heritable, modifiable risk factors for coronary artery disease. To identify new loci and refine known loci influencing these lipids, we examined 188,577 individuals using genome-wide and custom genotyping arrays. We identify and annotate 157 loci associated with lipid levels at P < 5 × 10(-8), including 62 loci not previously associated with lipid levels in humans. Using dense genotyping in individuals of European, East Asian, South Asian and African ancestry, we narrow association signals in 12 loci. We find that loci associated with blood lipid levels are often associated with cardiovascular and metabolic traits, including coronary artery disease, type 2 diabetes, blood pressure, waist-hip ratio and body mass index. Our results demonstrate the value of using genetic data from individuals of diverse ancestry and provide insights into the biological mechanisms regulating blood lipids to guide future genetic, biological and therapeutic research.
Cervical cancer is the second most common cancer in women. HLA class I and II alleles polymorphisms have been shown to associate with cervical cancer risk, but results varied among different populations. In this study, the HLA-A, -B, and -DRB1 alleles among 100 southern Chinese women with cervical squamous cell carcinoma (SCC) were compared to 254 controls. Our results showed that B*51:01:02 allele frequency was significantly higher in patients with SCC than that in healthy controls (P = 3.17x 10-5, Pc = 0.005, OR = 26.68). Statistical analysis also revealed a significantly decreased frequency of B*51:01:01 (P = 7.01x 10-4, Pc = 0.03, OR = 0.12) in patients with SCC when compared with healthy controls. These results indicate that HLA-B*51:01:02 may confer susceptibility to SCC and HLA-B*51:01:01 may contribute to the resistance to the development of SCC in Chinese women. None of the HLA-A-B or HLA-A-B-DRB1 haplotypes were significantly different in cases and controls after multiple testing corrections, implicating those individual allele associations are independent of the identified haplotypes. These results support the hypothesis that some HLA-B alleles could be involved with susceptibility for developing SCC.
Microcystin-leucine-arginine (MCLR) is an environmental toxin from harmful algae, which has been linked to hepatotoxicity with high risks associated with liver disease. In this study, we explored the role of MCLR in NF-?B and mitogen-activated protein kinase (MAPK) signaling pathways, which are important in regulating inflammatory and immune responses, in human hepatoma cell line HepG2 and primary mouse hepatocytes (PMHs). By in vitro cell-free and luciferase reporter systems, Western blotting with antiphospho-inhibitory protein of NF-?B (I?B?)/c-Jun N-terminal kinase (JNK)/extracellular signal-regulated kinase 1/2 (ERK1/2) antibody, it was found that at noncytotoxic concentrations (? 20 nM MCLR in PMHs, 1-1000 nM in HepG2), MCLR treatment alone promoted activation of NF-?B and MAPK pathways and modulated TNF-?-induced activation of the 2 pathways in both cell models. By ELISA assay, MCLR was found to induce production of proinflammatory cytokine IL-6 in PMHs. At cytotoxic concentrations (? 50 nM MCLR in PMHs), MCLR dramatically reduced cell viability and damaged cell morphology in PMHs, as determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and transmission electron microscopy analysis. These results suggest that MCLR below 20 nM has significant immunomodulatory activities through activation of NF-?B and MAPK signaling pathways, and PMHs are more sensitive to MCLR-induced cytotoxicity than HepG2. To our knowledge, this is the first report showing the immunomodulatory role of MCLR in hepatocytes. Our results provide a better understanding of the molecular mechanisms underlying MCLR-induced hepatotoxicity.
Virus-induced gene silencing (VIGS) system could be performed successfully in Gladiolus hybridus with vacuum infiltration of cormels and young plants. Functional analysis of genes in gladiolus has previously been impractical due to the lack of an efficient stable genetic transformation method. However, virus-induced gene silencing (VIGS) is effective in some plants which are difficult to transform through other methods. Although the Tobacco rattle virus (TRV)-based VIGS system has been developed and used for verifying gene functions in diverse plants, an appropriate TRV-VIGS approach for gladiolus has not been established yet. In this report we describe the first use of the TRV-VIGS system for gene silencing in gladiolus. Vacuum infiltration of cormels and young plants with the GhPDS-VIGS vector effectively down-regulated the PHYTOENE DESATURASE ortholog GhPDS gene and also resulted in various degrees of photobleaching in Gladiolus hybridus. The reduction in GhPDS expression was tested after TRV-based vector infection using real-time RT-PCR. In addition, the progress of TRV infection was detected by fluorescence visualization using a pTRV2: CP-GFP vector. In conclusion, the TRV-mediated VIGS described here will be an effective gene function analysis mechanism in gladiolus.
Pancreatic cancer is known for its bad prognosis. Micro-RNAs mis-expressions are associated with various human cancers and offer new candidate targets for diagnostic and therapeutic strategies. Micro-RNA-222 has been shown to play a crucial role in cancer cell proliferation in recent studies. However, its correlations with the clinicopathological characters of pancreatic cancer still remain unclear. Through a prospective study of 60 pairs of pancreatic cancer tissues, adjacent normal tissues were examined by quantitative reverse-transcription polymerase chain reaction. The correlation between the expression of micro-RNA-222 and clinico-pathological characters was performed using the two-sample Students t test. The survival correlations were analyzed by the Kaplan-Meier method and the Coxs proportional hazards model. Results showed that the expression levels of micro-RNA-222 were significantly elevated in the pancreatic cancer tissue compared with that in adjacent normal tissue. In addition, the overexpression of the tissue micro-RNA-222 strongly related to the expression level of Ki67. Finally, Coxs proportional hazards model analysis confirmed that micro-RNA-222 high expression level was an independent predictor of poor prognosis. This study provides the first evidence of a potential link between Ki67 and micro-RNA-222, which are both relevant to cell proliferation. Our data suggest the potential of micro-RNA-222 as a prognostic biomarker for the pancreatic cancer.
Recognition of the mRNA 5 m(7)G(5)ppp(5)N cap is key to translation initiation for most eukaryotic mRNAs. The cap is bound by the eIF4F complex, consisting of a cap-binding protein (eIF4E), a "scaffold" protein (eIF4G), and an RNA helicase (eIF4A). As a central early step in initiation, regulation of eIF4F is crucial for cellular viability. Although the structure and function of eIF4E have been defined, a dynamic mechanistic picture of its activity at the molecular level in the eIF4F?mRNA complex is still unavailable. Here, using single-molecule fluorescence, we measured the effects of Saccharomyces cerevisiae eIF4F factors, mRNA secondary structure, and the poly(A)-binding protein Pab1p on eIF4E-mRNA binding dynamics. Our data provide an integrated picture of how eIF4G and mRNA structure modulate eIF4E-mRNA interaction, and uncover an eIF4G- and poly(A)-independent activity of poly(A)-binding protein that prolongs the eIF4E?mRNA complex lifetime.
Contrast-induced acute kidney injury (CI-AKI) is a well-known serious complication of percutaneous coronary intervention (PCI) and may cause increased morbidity and mortality. We aim to identify the predictive value of Global Registry for Acute Coronary Events (GRACE) risk scores for CI-AKI in patients with ST-segment elevation myocardial infarction (STEMI) before primary PCI, allowing pre-procedural decisions regarding prevention therapy for CI-AKI.
Osteoporosis is a common disease characterized by low bone mass, microarchitectural deterioration of bone tissue and an increased risk of fracture. Population-based and case-control studies have identified polymorphisms in several candidate genes that have been associated with bone mass or osteoporotic fracture, including the vitamin D receptor (VDR), estrogen receptor (ER), oestrogen ? receptor (ESR), transforming growth factor (TGF)-?, and type I collagen. The Wnt signaling and receptor activator of nuclear factor ?B (RANK)/RANK ligand (RANK-L)/osteoprotegerin (OPG) pathways have been shown to play critical roles in determining bone mass and strength. An important aim of future work will be to further clarify the mechanisms involved in the interaction between candidate genes and environmental variables leading to osteoporosis via signaling pathways in individual patients. Hence preventative therapy, particularly gene therapy, could be targeted in patients at greatest risk of osteoporosis.
It has been known that osteoclastogenesis is induced by extracellular acidosis-evoked the rise of intracellular calcium ([Ca(2+)]i), which regulate activation of the transcription factor nuclear factor of activated T cells c1 (NFATc1). However, the acid-sensing ion channels (ASICs) involved remain largely unknown. Here, we show that ASIC1a, ASIC1b, ASIC2a, and ASIC3 are expressed in rat osteoclasts, and only ASIC1a is highly upregulated in response to acidosis. Both the ASIC1a-specific blocker PcTX1 and specific siRNA significantly reduce this increase in acid-induced [Ca(2+)]i and acid-induced nuclear translocation of NFATc1, and inhibit acid-induced osteoclast differentiation and bone resorption. These findings show that ASIC1a-mediated calcium entry plays a critical role in osteoclastogenesis by regulating activation of the NFATc1.
The use of bone marrow mononuclear cells (BM-MNCs) has achieved great outcomes in clinical practice. We aim to evaluate the efficacy and safety of autologous BM-MNC infusion and hyperbaric oxygen therapy (HOT) in type 2 diabetes mellitus.
Nuclear sensing of viral DNA has emerged as an essential step in innate immune responses against herpesviruses. Here, we provide mechanistic insight into host recognition of human cytomegalovirus (HCMV) and subsequent immune evasion by this prominent DNA virus. We establish that the interferon-inducible protein IFI16 acts as a nuclear DNA sensor following HCMV infection, binding viral DNA and triggering expression of antiviral cytokines via the STING-TBK1-IRF3 signaling pathway. The HCMV tegument protein pUL83 inhibits this response by interacting with the IFI16 pyrin domain, blocking its oligomerization upon DNA sensing and subsequent immune signals. pUL83 disrupts IFI16 by concerted action of its N- and C-terminal domains, in which an evolutionarily conserved N-terminal pyrin association domain (PAD) binds IFI16. Additionally, phosphorylation of the N-terminal domain modulates pUL83-mediated inhibition of pyrin aggregation. Collectively, our data elucidate the interplay between host DNA sensing and HCMV immune evasion, providing targets for restoring antiviral immunity.
Gastrointestinal stromal tumors (GISTs) occur rarely in the duodenum. Because of their low incidence, data on long-term survival and prognostic factors are limited. The aims of this study were to present the authors experiences in the diagnosis and treatment of this disease and to evaluate long-term surgical outcomes.
To more fully understand the mechanism by which persimmon tannin (PT) inhibited phospholipase A2 (PLA2) and the structural requirements of PT for the inhibition, the interactions between PLA2 and seven characteristic structural elements of PT including epigallocatechin-3-gallate (EGCG), myricetin, epicatechin-3-gallate (ECG), epicatechin-3-gallate-(4? ? 8, 2? ? O ? 7)-epicatechin-3-gallate (A-type ECG dimer), epigallocatechin-3-gallate-(4? ? 8, 2? ? O ? 7)-epigallocatechin-3-gallate (A-type EGCG dimer), epicatechin-(4? ? 8, 2? ? O ? 7)-epicatechin (A-type EC dimer) and epicatechin-(4? ? 8)-epicatechin (B-type EC dimer) were studied by enzymatic and spectroscopic methods. Molecular docking was also used to explore the possible residues involved in the interactions. The results revealed that A-type EGCG dimer and A-type ECG dimer showed higher inhibitory effects on the catalytic activity of PLA2 than monomers and B-type dimer. They induced greater conformational changes in PLA2 than other structural elements. In addition, molecular docking studies revealed that expect for lysine residues, other residues such as Trp18, Try27, Gly29, His47 and Tyr63 were involved in the interactions. We propose that A-type EGCG and ECG dimer units may be structural requirements for the interaction between PT and PLA2. Our data provide an additional structural basis for anti-PLA2 activity of persimmon tannin.
Nitrification plays a central role in global nitrogen cycle, which is affected by interaction between soil microfauna and microorganisms. The impact of synchronized changes in nematodes and ammonia oxidizers within aggregate fractions on nitrification was investigated in an acid soil under 10-year manure application. Nematodes, ammonia oxidizers and potential nitrification activity (PNA) were examined in three soil aggregate fractions under four fertilization regimes. Pyrosequencing data revealed that the dominant bacterial amoA operational taxonomic units (OTUs) were related to Nitrosospira species, while archaeal OTUs were affiliated with Nitrososphaera and Nitrosotalea species. PNA was more strongly correlated with ammonia-oxidizing bacteria (AOB) abundance than ammonia-oxidizing archaea (AOA) abundance, although AOA were dominant in the acid soil. Plant parasites had a negative effect on AOB abundance; however, bacterivores stimulated AOB abundance and contributed more to PNA than plant parasites. Aggregate fractions exerted significant impacts on AOA abundance and AOB community composition. Total carbon content strongly affected the abundance and composition of AOA community, while soil pH primarily affected that of AOB community. Soil variables explained 62.7% and 58.1% variations, and nematode variables explained 11.7% and 19.5% variations in the AOA and AOB community composition respectively.
Fisetin (3,3,4,7-tetrahydroxyflavone) has been reported to possess certain anticancer properties. It may inhibit tumor cell proliferation, metastasis and induce apoptosis. However, the effects of fisetin in preventing the metastasis of nasopharyngeal carcinoma (NPC) cells remain to be determined. The epithelial-mesenchymal transition (EMT) is involved in several metastatic malignancies including NPC. It has been reported that the Epstein-Barr virus latent membrane protein-1 (LMP1) induced EMT and is associated with the metastasis of NPC. The aim of this study was to examine the effects of fisetin in preventing the migration and invasion of LMP1-expressing NPC cells (CNE1-LMP1 cells), as well as to investigate whether fisetin may inhibit the molecular changes associated with EMT induced by LMP1. The investigation demonstrated that fisetin suppressed the migration and invasion of CNE1-LMP1 cells under non-cytotoxic concentrations. Fisetin inhibited molecular changes associated with EMT induced by LMP1, upregulated the epithelial marker, E-cadherin protein, and downregulated the mesenchymal marker, vimentin protein, levels. Fisetin also significantly reduced the levels of Twist protein, an EMT regulator. The investigation suggested that fisetin inhibits the migration and invasion of LMP1-positive NPC cells, and the molecular mechanism involves fisetin reversing the EMT induced by LMP1 and downregulates the expression of Twist. This study indicated that fisetin serves as a potential candidate for the treatment of cancer metastasis.
Background: Our previous study demonstrated cytotoxicity of a crude extract from Patrinia heterophylla Bunge (PHEB). In the present study, we aimed to investigate the effects of isovaltrate acetoxyhydrin (IA) isolated from PHEB on the gastric cancer cell SGC-7901, in order to explore a potential treatment for gastric cancer. Methods: MTT assays were employed to determine the effects of IA on cell vitality and proliferation, with monitoring of cell morphology changes and examination of apoptosis with Annexin V-PI staining. Flow cytometry was used to assess cell cycle progression and mitochondrial membrane potential. The activity of caspase 3, 9 was evaluated by spectrophotometry, and the protein levels of Bax, Bcl2 and Cyclin B1 were analyzed with Western blotting of total proteins extracted from cultured cells. Results: The results demonstrated direct toxicity of IA towards SGC-7901 cells. Evidence of apoptosis included blebbing and chromatin condensation. Annexin V-PI assays revealed early apoptosis, involving rapid depolarization of mitochondrial membranes and activity of caspase 3, 9 signaling pathways. Western blotting showed that Bcl2 and Bax proteins was down- and up-regulated, respectively, and cyclin B1 was up-regulated. Cell cycle analysis further indicated that IA could induce G2/M phase arrest in SGC-7901 cells. Conclusions: In conclusion, we believe that IA induces apoptosis of SGC-7901 cells, therefore providing a potential therapeutic agent for treatment of gastric cancer.
So far, relatively few studies have addressed the use of stem cells to treat patients with refractory angina. Moreover, the results of current studies were discrepant. The objective of this meta-analysis was to evaluate the efficacy and safety of this treatment on a relatively large scale.
Polybrominateddiphenyl ethers (PBDEs) are widely utilized as the additive brominated flame retardants in electronic devices, furniture, plastics, rubber foam, and textiles, which exhibit many negative biological effects, especially potential toxic effects on neurodevelopment. In the present study, we applied a proteomics approach to study the effects of decabromodiphenyl ether (BDE-209) and/or tetrabromodiphenyl ether (BDE-47) on the expression of proteins extracted from neural stem/progenitor cells and further explored mechanisms on neurodevelopmental toxicity. We sub-cultured 3-4 generations of neural stem/progenitor cells which were exposed to BDE-209 and/or BDE-47. After a 72-h exposure, we applied two-dimensional gel (2-DE) to identify differentially expressed proteins and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) to determine the protein identity of 25 spots. Western blot analysis was applied to determine the expression of cofilin-1 and vimentin. A total of 39 differential expression protein spots were identified by 2-DE after BDE-209 and/or BDE-47 exposure in the neural stem/progenitor cells, and 19 differentially expressed proteins were identified by MALDI-TOF-MS. Western blot analysis revealed that cofilin-1 and vimentin were differentially expressed in all groups. Expression of both proteins was decreased when the neural stem/progenitor cells were exposed to BDE-209 and were absent when exposed to both BDE-47 and BDE-209. BDE-209 and/or BDE-47 might alter the expression of some proteins of neural stem/progenitor cells. Nineteen proteins were identified by MALDI-TOF-MS, which will provide a useful basis for further study of the mechanisms underlying PBDE-mediated neurotoxicity.
Triglycerides are transported in plasma by specific triglyceride-rich lipoproteins; in epidemiological studies, increased triglyceride levels correlate with higher risk for coronary artery disease (CAD). However, it is unclear whether this association reflects causal processes. We used 185 common variants recently mapped for plasma lipids (P < 5 × 10(-8) for each) to examine the role of triglycerides in risk for CAD. First, we highlight loci associated with both low-density lipoprotein cholesterol (LDL-C) and triglyceride levels, and we show that the direction and magnitude of the associations with both traits are factors in determining CAD risk. Second, we consider loci with only a strong association with triglycerides and show that these loci are also associated with CAD. Finally, in a model accounting for effects on LDL-C and/or high-density lipoprotein cholesterol (HDL-C) levels, the strength of a polymorphisms effect on triglyceride levels is correlated with the magnitude of its effect on CAD risk. These results suggest that triglyceride-rich lipoproteins causally influence risk for CAD.
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