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Find video protocols related to scientific articles indexed in Pubmed.
Electrically-driven modulation of surface-grafted RGD peptides for manipulation of cell adhesion.
Chem. Commun. (Camb.)
PUBLISHED: 10-31-2014
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Reported herein is a switchable surface that relies on electrically-induced conformational changes within surface-grafted arginine-glycine-aspartate (RGD) oligopeptides as the means of modulating cell adhesion.
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Targeting RNA transcription and translation in ovarian cancer cells with pharmacological inhibitor CDKI-73.
Oncotarget
PUBLISHED: 10-04-2014
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Dysregulation of cellular transcription and translation is a fundamental hallmark of cancer. As CDK9 and Mnks play pivotal roles in the regulation of RNA transcription and protein synthesis, respectively, they are important targets for drug development. We herein report the cellular mechanism of a novel CDK9 inhibitor CDKI-73 in an ovarian cancer cell line (A2780). We also used shRNA-mediated CDK9 knockdown to investigate the importance of CDK9 in the maintenance of A2780 cells. This study revealed that CDKI-73 rapidly inhibited cellular CDK9 kinase activity and down-regulated the RNAPII phosphorylation. This subsequently caused a decrease in the eIF4E phosphorylation by blocking Mnk1 kinase activity. Consistently, CDK9 shRNA was also found to down-regulate the Mnk1 expression. Both CDKI-73 and CDK9 shRNA decreased anti-apoptotic proteins Mcl-1 and Bcl-2 and induced apoptosis. The study confirmed that CDK9 is required for cell survival and that ovarian cancer may be susceptible to CDK9 inhibition strategy. The data also implied a role of CDK9 in eIF4E-mediated translational control, suggesting that CDK9 may have important implication in the Mnk-eIF4E axis, the key determinants of PI3K/Akt/mTOR- and Ras/Raf/MAPK-mediated tumorigenic activity. As such, CDK9 inhibitor drug candidate CDKI-73 should have a major impact on these pathways in human cancers.
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Combined Strategies for Maintaining Skeletal Muscle Mass and Function in Aging: Myostatin Inactivation and AICAR-Associated Oxidative Metabolism Induction.
J. Gerontol. A Biol. Sci. Med. Sci.
PUBLISHED: 09-18-2014
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Myostatin (mstn) blockade, resulting in muscle hypertrophy, is a promising therapy to counteract age-related muscle loss. However, oxidative and mitochondrial deficit observed in young mice with myostatin inhibition could be detrimental with aging. The aim of this study was (a) to bring original data on metabolic and mitochondrial consequences of mstn inhibition in old mice, and (b) to examine whether 4-weeks of AICAR treatment, a pharmacological compound known to upregulate oxidative metabolism, may be useful to improve exercise capacity and mitochondrial deficit of 20-months mstn KO versus wild-type (WT) mice. Our results show that despite the enlarged muscle mass, the oxidative and mitochondrial deficit associated with reduced endurance running capacity is maintained in old mstn KO mice but not worsened by aging. Importantly, AICAR treatment induced a significant beneficial effect on running limit time only in old mstn KO mice, with a marked increase in PGC-1? expression and slight beneficial effects on mitochondrial function. We showed that AICAR effects were autophagy-independent. This study underlines the relevance of aged muscle remodelling by complementary approaches that impact both muscle mass and function, and suggest that mstn inhibition and aerobic metabolism activators should be co-developed for delaying age-related deficits in skeletal muscle.
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International validation of the Chinese University Prognostic Index for staging of hepatocellular carcinoma: a joint United Kingdom and Hong Kong study.
Chin J Cancer
PUBLISHED: 09-16-2014
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The outcome of hepatocellular carcinoma (HCC) patients significantly differs between western and eastern population centers. Our group previously developed and validated the Chinese University Prognostic Index (CUPI) for the prognostication of HCC among the Asian HCC patient population. In the current study, we aimed to validate the CUPI using an international cohort of patients with HCC and to compare the CUPI to two widely used staging systems, the Barcelona Clinic Liver Cancer (BCLC) classification and the Cancer of the Liver Italian Program (CLIP). To accomplish this goal, two cohorts of patients were enrolled in the United Kingdom (UK; n = 567; 2006-2011) and Hong Kong (HK; n = 517; 2007-2012). The baseline clinical data were recorded. The performances of the CUPI, BCLC, and CLIP were compared in terms of a concordance index (C-index) and were evaluated in subgroups of patients according to treatment intent. The results revealed that the median follow-up durations of the UK and HK cohorts were 27.9 and 29.8 months, respectively. The median overall survival of the UK and HK cohorts were 22.9 and 8.6 months, respectively. The CUPI stratified the patients in both cohorts into three risk subgroups corresponding to distinct outcomes. The median overall survival of the CUPI low-, intermediate-, and high-risk subgroups were 3.15, 1.24, and 0.29 years, respectively, in the UK cohort and were 2.07, 0.32, and 0.10 years, respectively, in the HK cohort. For the patients who underwent curative treatment, the prognostic performance did not differ between the three staging systems, and all were suboptimal. For those who underwent palliative treatment, the CUPI displayed the highest C-index, indicating that this staging system was the most informative for both cohorts. In conclusion, the CUPI is applicable to both western and eastern HCC patient populations. The performances of the three staging systems differed according to treatment intent, and the CUPI was demonstrated to be optimal for those undergoing palliative treatment. A more precise staging system for early-stage disease patients is required.
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"I can't sleep!": gathering the evidence for an innovative intervention for insomnia in cancer patients.
Can Oncol Nurs J
PUBLISHED: 09-06-2014
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Sleep-wake disturbances, in particular insomnia, are experienced by 30%-75% of oncology patients, yet no effective interventions have been designed to address this distressing symptom in the ambulatory setting. In response to an identified gap in care, I share the development and evaluation of an innovative sleep intervention designed specifically for the ambulatory setting. Preliminary findings, as well as an informative blueprint for conducting point-of-care research, are described. As a "bedside" nurse it is possible and within our moral imperative and social justice mandate to take action to find evidence-informed solutions to improve care for populations of patients experiencing gaps in care. The "I" used throughout the article refers to the lead author Surya.
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Switching specific biomolecular interactions on surfaces under complex biological conditions.
Analyst
PUBLISHED: 09-03-2014
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Herein, electrically switchable mixed self-assembled monolayers based on oligopeptides have been developed and investigated for their suitability in achieving control over biomolecular interactions in the presence of complex biological conditions. Our model system, a biotinylated oligopeptide tethered to gold within a background of tri(ethylene glycol) undecanethiol, is ubiquitous in both switching specific protein interactions in highly fouling media while still offering the non-specific protein-resistance to the surface. Furthermore, the work demonstrated that the performance of the switching on the electro-switchable oligopeptide is sensitive to the characteristics of the media, and in particular, its protein concentration and buffer composition, and thus such aspects should be considered and addressed to assure maximum switching performance. This study lays the foundation for developing more realistic dynamic extracellular matrix models and is certainly applicable in a wide variety of biological and medical applications.
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Crystal structure of di-?-benzato-?(4) O:O'-bis-[aqua-(benzato-?O)(benzato-?(2) O,O')(2,2':6',2''-terpyridine-?(3) N,N',N'')europium(III)]-benzoic acid (1/2).
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-01-2014
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The title compound, [Eu2(C7H5O2)6(C15H11N3)2(H2O)2]·2C7H6O2, is a co-crystalline compound containing a dinuclear Eu(III) coordination complex with inversion symmetry co-crystallized with benzoic acid in a 1:2 ratio. The Eu(3+) ions within the dimer are nine-coordinate, containing one tridentate terpyridine, one water, and four benzoate ions, two of which bridge the Eu(3+) ions. Of the four benzoate ligands coordinating to each Eu(3+) position, three distinct coordination modes [monodentate, bidentate-chelating, and bidentate-bridging (twice)] are observed. Within the crystal, there are two additional uncoordinating benzoic acid mol-ecules per dinuclear complex. Within the dimer, the water bound to each Eu(3+) ion participates in intra-molecular hydrogen bonding with a coordinating benzoate. Additionally, the carb-oxy-lic acid group on the benzoic acid participates in inter-molecular hydrogen bonding with a benzoate ligand bound to the dimer complex.
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Crystal structure of catena-poly[[aqua(2,2':6',2''-terpyridine-?(3) N,N',N'')cobalt(II)]-?-cyanido-?(2) N:C-[dicyanidoplatinum(II)]-?-cyanido-?(2) C:N].
Acta Crystallogr Sect E Struct Rep Online
PUBLISHED: 09-01-2014
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The title compound, [Co(C15H11N3)(H2O){Pt(CN)4}] n , is a one-dimensional coordination polymer formed under hydro-thermal reaction conditions. The Co(II) site has sixfold coordination with a distorted octa-hedral geometry, while the Pt(II) ion is coordinated by four cyanide groups in an almost regular square-planar geometry. The compound contains twofold rotation symmetry about its Co(II) ion, the water molecule and the terpyridine ligand, and the Pt(II) atom resides on an inversion center. trans-Bridging by the tetra-cyanidoplatinate(II) anions links the Co(II) cations, forming chains parallel to [-101]. Additionally, each Co(II) atom is coordin-ated by one water mol-ecule and one tridentate 2,2':6',2''-terpyridine ligand. O-H?N hydrogen-bonding inter-actions are found between adjacent chains and help to consolidate the crystal packing. In addition, relatively weak ?-? stacking inter-actions exist between the terpyridine ligands of adjacent chains [inter-planar distance = 3.464?(7)?Å]. No Pt?Pt inter-actions are observed in the structure.
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Client and provider views on access to care for substance-using American Indians: perspectives from a Northern Plains urban clinic.
Am Indian Alsk Native Ment Health Res
PUBLISHED: 08-12-2014
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In addition to disparities in rates of substance use problems, American Indians (AIs) report multiple barriers to receiving treatment services. The present study utilized intake questionnaire data and focus groups to gain perspectives from 152 clients (65% male, 35% female; mean age 30 years) and 6 female providers on access to treatment for Northern Plains AIs in an urban, non-Native program. AI clients acknowledged the need for treatment more often than did substance users in general, but faced greater resource barriers. Both clients and providers offered specific recommendations for improving access to substance use treatment for AI populations in the Northern Plains.
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Mixed halogenated dioxins/furans (PXDD/Fs) and biphenyls (PXBs) in food: Occurrence and toxic equivalent exposure using specific relative potencies.
Environ Int
PUBLISHED: 08-09-2014
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The occurrence of nineteen mixed halogenated (bromo-chloro) dibenzo-p-dioxins, dibenzofurans (PXDD/Fs) and biphenyls (PXBs) in a range of foods (n>100) was investigated. The analytical methodology used dual activated carbon column fractionation with high resolution mass spectrometric measurement (13,500-15,000 res). Occurrence was observed in most commonly consumed foods but the most frequent detections of these environmental contaminants were made in shellfish and offal. The concentrations of the individual compounds were condensed into toxic equivalents (TEQs) using recently reported relative potency values. Although representing only a small subset of the full range of toxic PXDD/Fs and PXBs, the TEQs estimated for these compounds ranged from 0.2% to approximately 15% (depending on the food matrix) of the corresponding TEQ for the fully chlorinated analogues. This finding is of great toxicological importance as it implies that a potentially greater magnitude of TEQ could be associated with the full range of toxic PXDD/Fs and PXBs, thus making a significant contribution to dioxin-like toxicity from the diet, to human exposure.
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Perforin gene mutation in familial haemophagocytic lymphohistiocytosis: the first reported case from Hong Kong.
Hong Kong Med J
PUBLISHED: 08-09-2014
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Familial haemophagocytic lymphohistiocytosis is a rare but invariably fatal disease without haematopoietic stem cell transplantation. Genetic defect identification is useful for confirming a clinical diagnosis, predicting the risk of future recurrence, and defining haemophagocytic lymphohistiocytosis predisposition in asymptomatic family members. Notably, familial haemophagocytic lymphohistiocytosis type 2 associates with mutations in the perforin gene (PRF1) which is the most frequent subtype of familial haemophagocytic lymphohistiocytosis. Although perforin gene mutations have been described in Asians, they are largely reported from Japan. The case reported here is the first familial haemophagocytic lymphohistiocytosis type 2 patient in Hong Kong with an identified perforin gene mutation.
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Pilot trial study of a compact macro-filtration membrane bioreactor process for saline wastewater treatment.
Water Sci. Technol.
PUBLISHED: 07-16-2014
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Conventional membrane bioreactor (MBR) systems have increasingly been studied in recent decades. However, their applications have been limited due to their drawbacks such as low flux, membrane fouling, and high operating cost. In this study, a compact macro-filtration MBR (MfMBR) process was developed by using a large pore size membrane to mitigate the membrane fouling problem. A pilot trial of MfMBR process was set up and operated to treat 10 m(3)/day of saline wastewater within 4 h. The system was operated under an average permeate flux of 13.1 m(3)/(m(2)·day) for 74 days. The average total suspended solids, total chemical oxygen demand, biological oxygen demand, total Kjeldahl nitrogen, and total nitrogen removal efficiencies achieved were 94.3, 83.1, 98.0, 93.1, and 63.3%, respectively, during steady-state operation. The confocal laser scanning microscopy image indicated that the backwash could effectively remove the bio-cake and dead bacteria. Thus, the results showed that the MfMBR process, which is essentially a primary wastewater treatment process, had the potential to yield the same high quality effluent standards as the secondary treatment process; thereby suggesting that it could be used as an option when the economic budget and/or land space is limited.
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Septic arthritis caused by Brucella melitensis in urban Shenzhen, China: a case report.
J Med Case Rep
PUBLISHED: 06-14-2014
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Brucellosis is a systemic infectious disease which is still a challenging medical problem in rural areas such as northern China. It rarely occurs in urban areas such as Shenzhen in southern China. Osteoarticular involvements are frequently seen in brucellosis, and rarely is arthritis the only clinical presentation. We report a case of hip septic arthritis caused by Brucella melitensis in an urban area of Shenzhen, China.
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[Application of three-dimensional printing technique in orthopaedics].
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi
PUBLISHED: 05-22-2014
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To review the current progress of three-dimensional (3-D) printing technique in the clinical practice, its limitations and prospects.
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Development of an animal fracture model for evaluation of cement augmentation femoroplasty: an in vitro biomechanical study.
Biores Open Access
PUBLISHED: 05-08-2014
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Osteoporotic hip fracture is the most severe kind of fracture with high morbidity and mortality. Patients' ambulation and quality of life are significantly affected by the fracture because only 50% regain their prefracture functional status, even if they undergo surgeries. There are many issues associated with the current preventive methods e.g., cost, side effects, patient compliance, and time for onset of action. Femoroplasty, the injection of bone cement into the proximal femur to augment femoral strength and to prevent fracture, has been an option with great potential. However, until now femoroplasty has remained at the stage of biomechanical testing. No in vivo study has evaluated its safety and effectiveness; there is not even an animal model for such investigations. The objective of this study was to develop a proximal femur fracture goat model that consistently fractures at the proximal femur when subject to vertical load, simulating osteoporotic hip fractures in human. Six pairs of fresh frozen mature Chinese goats' femora were obtained and randomly assigned into two groups. For the experimental group, a cylindrical bone defect was created at the proximal femur, while the control was left untreated. In addition, a configuration to mimic the mechanical axis of the goat femur was developed. When subjected to load along the mechanical axis, all the specimens from the bone defect group experienced femoral neck fractures, while fractures occurred at the femoral neck or other sites of the proximal femur in the control group. The biomechanical property (failure load) of the bone defect specimens was significantly lower than that of the control specimens (p<0.05). Osteoporotic hip fractures of humans were simulated by a goat fracture model, which may serve as a reference for future femoroplasty studies in vivo. The newly developed configuration simulating a femoral mechanical axis for biomechanical tests was practicable during the study.
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Surface molecular tailoring using pH-switchable supramolecular dendron-ligand assemblies.
ACS Appl Mater Interfaces
PUBLISHED: 05-01-2014
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The rational design of materials with tailored properties is of paramount importance for a wide variety of biological, medical, electronic and optical applications. Here we report molecular level control over the spatial distribution of functional groups on surfaces utilizing self-assembled monolayers (SAMs) of pH-switchable surface-appended pseudorotaxanes. The supramolecular systems were constructed from a poly(aryl ether) dendron-containing a dibenzo[24]crown-8 (DB24C8) macrocycle and a thiol ligand-containing a dibenzylammonium recognition site and a fluorine end group. The dendron establishes the space (dendritic effect) that each pseudorotaxane occupies on the SAM. Following SAM formation, the dendron is released from the surface by switching off the noncovalent interactions upon pH stimulation, generating surface materials with tailored physical and chemical properties.
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Baseline adiponectin levels do not influence the response to pioglitazone in ACT NOW.
Diabetes Care
PUBLISHED: 04-04-2014
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Plasma adiponectin levels are reduced in type 2 diabetes mellitus (T2DM) and other insulin-resistant states. We examined whether plasma adiponectin levels at baseline and after pioglitazone treatment in impaired glucose tolerance (IGT) subjects were associated with improved insulin sensitivity (SI) and glucose tolerance status.
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Propagation of bisphosphonate-related femoral stress fractures despite femoral nailing: a cautionary tale from 2 cases.
Geriatr Orthop Surg Rehabil
PUBLISHED: 03-25-2014
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We report 2 cases of atypical femoral fracture displacement despite treatment with intramedullary (IM) nailing. Both patients had received more than 3 years of bisphosphonates. One patient had prophylactic fixation of an atypical femur fracture due to intractable pain. The other had undergone nailing previously for a traumatic shaft fracture. The patient then received bisphosphonate later and sustained an atypical fracture with the nail in place. Both femoral nails were slotted, cannulated stainless steel piriformis entry designs. These 2 cases are among the first reported failures of IM fixation in preventing displacement of a bisphosphonate stress fracture. We advice caution when using slotted nails in prophylaxis of atypical femur fractures because of its significantly reduced torsional stiffness compared to modern nonopen sectioned nails.
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Electrochemical detection of intracellular and cell membrane redox systems in Saccharomyces cerevisiae.
Sci Rep
PUBLISHED: 03-20-2014
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Redox mediators can interact with eukaryote cells at a number of different cell locations. While cell membrane redox centres are easily accessible, the redox centres of catabolism are situated within the cytoplasm and mitochondria and can be difficult to access. We have systematically investigated the interaction of thirteen commonly used lipophilic and hydrophilic mediators with the yeast Saccharomyces cerevisiae. A double mediator system is used in which ferricyanide is the final electron acceptor (the reporter mediator). After incubation of cells with mediators, steady state voltammetry of the ferri/ferrocyanide redox couple allows quantitation of the amount of mediator reduced by the cells. The plateau current at 425 mV vs Ag/AgCl gives the analytical signal. The results show that five of the mediators interact with at least three different trans Plasma Membrane Electron Transport systems (tPMETs), and that four mediators cross the plasma membrane to interact with cytoplasmic and mitochondrial redox molecules. Four of the mediators inhibit electron transfer from S. cerevisiae. Catabolic inhibitors were used to locate the cellular source of electrons for three of the mediators.
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Discovery of (E)-3-((styrylsulfonyl)methyl)pyridine and (E)-2-((styrylsulfonyl)methyl)pyridine derivatives as anticancer agents: synthesis, structure-activity relationships, and biological activities.
J. Med. Chem.
PUBLISHED: 03-10-2014
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ON01910.Na is a highly effective anticancer agent that induces mitotic arrest and apoptosis. Clinical studies with ON01910 in cancer patients have shown efficacy along with an impressive safety profile. While ON01910 is highly active against cancer cells, it has a low oral availability and requires continuous intravenous infusion or multiple gram doses to ensure sufficient drug exposure for biological activity in patients. We have identified two novel series of styrylsulfonyl-methylpyridines. Lead compounds 8, 9a, 18 and 19a are highly potent mitotic inhibitors and selectively cytotoxic to cancer cells. Impressively, these compounds possess excellent pharmaceutical properties and two lead drug candidates 9a and 18 demonstrated antitumor activities in animal models.
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Fungal otomastoiditis: a case series in immunocompetent adults.
Indian J Otolaryngol Head Neck Surg
PUBLISHED: 03-08-2014
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Fungal otomastoiditis is a rare condition and is usually associated with host immunodeficiency. It is difficult to diagnose, and many cases are fatal. Treatment consists of surgical debridement, attempts to control the underlying immunological condition and antifungal chemotherapy. Individual case reports in immunocompetent patients have been published previously. We report a case series of seven with fungal otomastoiditis, all in immunocompetent patients.
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Discovery of 5-(2-(phenylamino)pyrimidin-4-yl)thiazol-2(3H)-one derivatives as potent Mnk2 inhibitors: synthesis, SAR analysis and biological evaluation.
ChemMedChem
PUBLISHED: 02-12-2014
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Phosphorylation of eIF4E by human mitogen-activated protein kinase (MAPK)-interacting kinases (Mnks) is crucial for human tumourigenesis and development. Targeting Mnks may provide a novel anticancer therapeutic strategy. However, the lack of selective Mnk inhibitors has so far hampered pharmacological target validation and clinical drug development. Herein, we report, for the first time, the discovery of a series of 5-(2-(phenylamino)pyrimidin-4-yl)thiazole-2(3H)-one derivatives as Mnk inhibitors. Several derivatives demonstrate very potent Mnk2 inhibitory activity. The most active and selective compounds were tested against a panel of cancer cell lines, and the results confirm the cell-type-specific effect of these Mnk inhibitors. Detailed cellular mechanistic studies reveal that Mnk inhibitors are capable of reducing the expression level of anti-apoptotic protein Mcl-1, and of promoting apoptosis in MV4-11 acute myeloid leukaemia cells.
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Is helical blade superior to screw design in terms of cut-out rate for elderly trochanteric fractures? A meta-analysis of randomized controlled trials.
Eur J Orthop Surg Traumatol
PUBLISHED: 02-08-2014
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This meta-analysis was conducted to investigate whether helical blade implant system had advantages in terms of cut-out rate when compared to screw implant system for trochanteric fractures of elderly population.
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Measurement of the "safe zone" and the "dangerous zone" for the screw placement on the quadrilateral surface in the treatment of pelvic and acetabular fractures with Stoppa approach by computational 3D technology.
Biomed Res Int
PUBLISHED: 01-29-2014
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This study is aimed at definition of the safe and dangerous zone for screw placement with Stoppa approach for rapid identification during operation and a new way for the studies on the "safe zone." Pelvic CT data of 84 human subjects were recruited to reconstruct the three-dimensional (3D) models. The distances between the edges of the "safe zone," "dangerous zone," and specific anatomic landmarks such as the obturator canal and the pelvic brim were precisely measured, respectively. The results show that the absolute "dangerous zone" was from the pelvic brim to 3.07?cm below it and within 2.86?cm of the obturator canal, while the region 3.56?cm below the pelvic brim or 3.85?cm away from the obturator canal was the absolute "safe zone" for screw placement. The region between the absolute "safe zone" and the absolute "dangerous zone" was the relatively "dangerous zone." As a conclusion, application of computer-assisted 3D modeling techniques aids in the precise measurement of "safe zone" and "dangerous zone" in combination with Stoppa incision. It was not recommended to place screws on the absolute dangerous zone, while, for the relatively "dangerous zone," it depends on the individual variations in bony anatomy and the fracture type.
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Real-time electrocatalytic sensing of cellular respiration.
Biosens Bioelectron
PUBLISHED: 01-17-2014
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In the present work we develop a real-time electrochemical mediator assay to enable the assessment of cell numbers and chemical toxicity. This allowed us to monitor metabolism down to a single cell in a low cost easy to use rapid assay which is not possible with current technology. The developed assay was based on the determination of oxygen. This was made possible via the use of electrochemical mediator ferrocene carboxylic acid (FcA). The FcA showed distinctive catalytic properties in interacting with reactive oxygen species generated from oxygen when compared to ferrocene methanol (FcMeOH). A deeper insight into the chemistry controlling this behaviour is provided. The behaviour is then taken advantage of to develop a cellular aerobic respiration assay. We describe the properties of the FcA system to detect, in real-time, the oxygen consumption of Escherichia coli DH5-? (E. coli). We demonstrated that the FcA-based oxygen assay is highly sensitive, and using a population of cells, oxygen consumption rates could be calculated down to a single cell level. More importantly, the results can be accomplished in minutes, considerably outperforming current commercially available biooxygen demand assays. The developed assay is expected to have a significant impact in diverse fields and industries, ranging from environmental toxicology through to pharmaceutical and agrochemical industries.
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Acceptability of a Web-Based Community Reinforcement Approach for Substance Use Disorders with Treatment-Seeking American Indians/Alaska Natives.
Community Ment Health J
PUBLISHED: 01-07-2014
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Longstanding disparities in substance use disorders and treatment access exist among American Indians/Alaska Natives (AI/AN). Computerized, web-delivered interventions have potential to increase access to quality treatment and improve patient outcomes. Prior research supports the efficacy of a web-based version [therapeutic education system (TES)] of the community reinforcement approach to improve outcomes among outpatients in substance abuse treatment; however, TES has not been tested among AI/AN. The results from this mixed method acceptability study among a diverse sample of urban AI/AN (N = 40) show that TES was acceptable across seven indices (range 7.8-9.4 on 0-10 scales with 10 indicating highest acceptability). Qualitative interviews suggest adaptation specific to AI/AN culture could improve adoption. Additional efforts to adapt TES and conduct a larger effectiveness study are warranted.
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Masquelet technique for treatment of posttraumatic bone defects.
ScientificWorldJournal
PUBLISHED: 01-01-2014
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Masquelet technique, which is the use of a temporary cement spacer followed by staged bone grafting, is a recent treatment strategy to manage a posttraumatic bone defect. This paper describes a series of 9 patients treated with this technique of staged bone grafting following placement of an antibiotic spacer to successfully manage osseous long bone defects. The injured limbs were stabilized and aligned at the time of initial spacer placement. In our series, osseous consolidation was successfully achieved in all cases. This technique gives promising result in the management of posttraumatic bone defects.
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Unresectable Hepatocellular Carcinoma: Randomized Controlled Trial of Transarterial Ethanol Ablation versus Transcatheter Arterial Chemoembolization.
Radiology
PUBLISHED: 10-28-2013
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Purpose:To compare effectiveness of transarterial ethanol ablation (TEA) and transcatheter arterial chemoembolization (TACE) for unresectable hepatocellular carcinoma and determine whether TEA leads to better overall survival and tumor response than TACE.Materials and Methods:In this institutional review board-approved preregistered randomized controlled trial (n = 200), informed consent was obtained. Primary outcome was overall survival; secondary outcomes were time to progression (TTP), progression-free survival (PFS), tumor response at computed tomography, and treatment-related toxicity. Eligible patients were randomized at a 1:1 ratio. Treatment included transcatheter delivery of ethiodized oil-ethanol mixture (2:1 ratio by volume up to 60 mL) for TEA and cisplatin-ethiodized oil emulsion (0.5 mg cisplatin per milliliter up to 30 mg), followed by 1-mm gelatin-sponge pellets, for TACE. Study was terminated after interim analysis (n = 98); 90 patients were available for analysis. Overall survival, TTP, and PFS were analyzed with Kaplan-Meier method; differences were compared with log-rank test.Results:Study was terminated prematurely after interim analysis, which showed no difference in overall survival; this was unlikely to change with further patient accrual. Median overall survival in TEA and TACE was 24.3 months (95% confidence interval [CI]: 12.8, 32.7) and 20.1 months (95% CI: 9.3, 31.2), respectively (P = .358). Median TTP and PFS for intralesional progression were longer with TEA than TACE (TTP, 34.6 months [95% CI: 28.2, 41] vs 26.05 months [95% CI: 18.7, 33.3]; PFS, 14.8 months [95% CI: 10.2, 19.5] vs 9.3 months [95% CI: 7.1, 11.5]) (P = .028 and 0.029, respectively). Complete response rate on a tumor basis was persistently and significantly higher with TEA at 3 months (62 of 88 [70%] vs 39 of 76 [51%], P = .012), 6 months (64 of 88 [73%] vs 41 of 76 [54%], P = .012), and 12 months (66 of 88 [75%] vs 45 of 76 [59%], P = .031).Conclusion:Although there was no significant difference in overall survival, TEA demonstrated better complete tumor response, longer time to intralesional progression, and longer PFS.© RSNA, 2013Clinical trial registration no. NCT00467974.
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Prediction of diabetes based on baseline metabolic characteristics in individuals at high risk.
Diabetes Care
PUBLISHED: 09-23-2013
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Individuals with impaired glucose tolerance (IGT) are at high risk for developing type 2 diabetes mellitus (T2DM). We examined which characteristics at baseline predicted the development of T2DM versus maintenance of IGT or conversion to normal glucose tolerance.
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Conversion of Fusaric Acid to Fusarinol by Aspergillus tubingensis: A Detoxification Reaction.
J. Chem. Ecol.
PUBLISHED: 09-20-2013
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The fungus Fusarium oxysporum causes wilt diseases of plants and produces a potent phytotoxin fusaric acid (FA), which is also toxic to many microorganisms. An Aspergillus tubingensis strain with high tolerance to FA was isolated from soil and designated as CDRAt01. HPLC analysis of culture filtrates from A. tubingensis isolate CDRAt01 grown with the addition of FA indicated the formation of a metabolite over time that was associated with a decrease of FA. Spectral analysis and chemical synthesis confirmed the compound as 5-butyl-2-pyridinemethanol, referred to here as fusarinol. The phytotoxicity of fusarinol compared to FA was measured by comparing necrosis induced in cotton (Gossypium hirsutum L. cv. Coker 312) cotyledons. Fusarinol was significantly less phytotoxic than FA. Therefore, the A. tubingensis strain provides a novel detoxification mechanism against FA which may be utilized to control Fusarium wilt.
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Adjuvant docetaxel and cyclophosphamide plus trastuzumab in patients with HER2-amplified early stage breast cancer: a single-group, open-label, phase 2 study.
Lancet Oncol.
PUBLISHED: 09-03-2013
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Previous results suggest that docetaxel plus cyclophosphamide improves disease-free survival (DFS) and overall survival compared with doxorubicin plus cyclophosphamide in early stage breast cancer. We assessed the addition of 1 year of trastuzumab to a non-anthracycline regimen, docetaxel plus cyclophosphamide, in patients with HER2-amplified early stage breast cancer and examined whether this regimen was equally effective in patients with TOP2A-amplified and TOP2A-non-amplified disease.
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Achieving smoking abstinence is associated with decreased cocaine use in cocaine-dependent patients receiving smoking-cessation treatment.
Drug Alcohol Depend
PUBLISHED: 08-28-2013
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Past research suggests that a significant relationship exists between cigarette smoking and illicit-stimulant abuse. The present study evaluated the association between achieving smoking abstinence in response to smoking-cessation treatment (SCT) and illicit-stimulant abstinence in cocaine- and/or methamphetamine-dependent participants.
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The effectiveness of a geriatric hip fracture clinical pathway in reducing hospital and rehabilitation length of stay and improving short-term mortality rates.
Geriatr Orthop Surg Rehabil
PUBLISHED: 08-13-2013
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A geriatric hip fracture clinical pathway, led by an orthopedic surgeon, was developed in 2007. This clinical pathway team is multidisciplinary and consists of surgeons, physicians, anesthetists, nurses, physiotherapists, occupational therapists, medical social workers, dieticians as well as voluntary support groups.
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In vivo stimulation of bone formation by aluminum and oxygen plasma surface-modified magnesium implants.
Biomaterials
PUBLISHED: 07-28-2013
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A newly developed magnesium implant is used to stimulate bone formation in vivo. The magnesium implant after undergoing dual aluminum and oxygen plasma implantation is able to suppress rapid corrosion, leaching of magnesium ions, as well as hydrogen gas release from the biodegradable alloy in simulated body fluid (SBF). No released aluminum is detected from the SBF extract and enhanced corrosion resistance properties are confirmed by electrochemical tests. In vitro studies reveal enhanced growth of GFP mouse osteoblasts on the aluminum oxide coated sample, but not on the untreated sample. In addition to that a small amount (50 ppm) of magnesium ions can enhance osteogenic differentiation as reported previously, our present data show a low concentration of hydrogen can give rise to the same effect. To compare the bone volume change between the plasma-treated magnesium implant and untreated control, micro-computed tomography is performed and the plasma-treated implant is found to induce significant new bone formation adjacent to the implant from day 1 until the end of the animal study. On the contrary, bone loss is observed during the first week post-operation from the untreated magnesium sample. Owing to the protection offered by the Al2O3 layer, the plasma-treated implant degrades more slowly and the small amount of released magnesium ions stimulate new bone formation locally as revealed by histological analyses. Scanning electron microscopy discloses that the Al2O3 layer at the bone-implant interface is still present two months after implantation. In addition, no inflammation or tissue necrosis is observed from both treated and untreated implants. These promising results suggest that the plasma-treated magnesium implant can stimulate bone formation in vivo in a minimal invasive way and without causing post-operative complications.
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Dosimetric difference amongst 3 techniques: TomoTherapy, sliding-window intensity-modulated radiotherapy (IMRT), and RapidArc radiotherapy in the treatment of late-stage nasopharyngeal carcinoma (NPC).
Med Dosim
PUBLISHED: 07-24-2013
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To investigate the dosimetric difference amongst TomoTherapy, sliding-window intensity-modulated radiotherapy (IMRT), and RapidArc radiotherapy in the treatment of late-stage nasopharyngeal carcinoma (NPC). Ten patients with late-stage (Stage III or IV) NPC treated with TomoTherapy or IMRT were selected for the study. Treatment plans with these 3 techniques were devised according to departmental protocol. Dosimetric parameters for organ at risk and treatment targets were compared between TomoTherapy and IMRT, TomoTherapy and RapidArc, and IMRT and RapidArc. Comparison amongst the techniques was done by statistical tests on the dosimetric parameters, total monitor unit (MU), and expected delivery time. All 3 techniques achieved similar target dose coverage. TomoTherapy achieved significantly lower doses in lens and mandible amongst the techniques. It also achieved significantly better dose conformity to the treatment targets. RapidArc achieved significantly lower dose to the eye and normal tissue, lower total MU, and less delivery time. The dosimetric advantages of the 3 techniques were identified in the treatment of late-stage NPC. This may serve as a guideline for selection of the proper technique for different clinical cases.
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Training status and sex influence on senescent T-lymphocyte redistribution in response to acute maximal exercise.
Brain Behav. Immun.
PUBLISHED: 07-22-2013
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Investigate training status and sex effects on the redistribution of senescent and naïve T-lymphocytes following acute exercise.
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Prevention of diabetes with pioglitazone in ACT NOW: physiologic correlates.
Diabetes
PUBLISHED: 07-17-2013
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We examined the metabolic characteristics that attend the development of type 2 diabetes (T2DM) in 441 impaired glucose tolerance (IGT) subjects who participated in the ACT NOW Study and had complete end-of-study metabolic measurements. Subjects were randomized to receive pioglitazone (PGZ; 45 mg/day) or placebo and were observed for a median of 2.4 years. Indices of insulin sensitivity (Matsuda index [MI]), insulin secretion (IS)/insulin resistance (IR; ?I0-120/?G0-120, ?IS rate [ISR]0-120/?G0-120), and ?-cell function (?I/?G × MI and ?ISR/?G × MI) were calculated from plasma glucose, insulin, and C-peptide concentrations during oral glucose tolerance tests at baseline and study end. Diabetes developed in 45 placebo-treated vs. 15 PGZ-treated subjects (odds ratio [OR] 0.28 [95% CI 0.15-0.49]; P < 0.0001); 48% of PGZ-treated subjects reverted to normal glucose tolerance (NGT) versus 28% of placebo-treated subjects (P < 0.005). Higher final glucose tolerance status (NGT > IGT > T2DM) was associated with improvements in insulin sensitivity (OR 0.61 [95% CI 0.54-0.80]), IS (OR 0.61 [95% CI 0.50-0.75]), and ?-cell function (ln IS/IR index and ln ISR/IR index) (OR 0.26 [95% CI 0.19-0.37]; all P < 0.0001). Of the factors measured, improved ?-cell function was most closely associated with final glucose tolerance status.
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Multi-institutional analysis of long-term symptom resolution after cholecystectomy for biliary dyskinesia in children.
Pediatr. Surg. Int.
PUBLISHED: 07-02-2013
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Current literature for resolution of abdominal pain after cholecystectomy in children with biliary dyskinesia shows variable outcomes. We sought to compare early outcomes with long-term symptom resolution in children.
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Synthesis, structure-activity relationship and biological evaluation of 2,4,5-trisubstituted pyrimidine CDK inhibitors as potential anti-tumour agents.
Eur J Med Chem
PUBLISHED: 06-18-2013
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A series of 2,4,5-trisubstituted pyrimidines have been synthesised and characterised, which exhibited potent CDK inhibition and anti-proliferative activities. The structure-activity relationship is analysed and a rational for CDK9 selectivity is discussed. Compound 9s, possessing appreciable selectivity for CDK9 over other CDKs, is capable of activating caspase 3, reducing the level of Mcl-1 anti-apoptotic protein, and inducing cancer cell apoptosis.
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Regulation of deleted in liver cancer 1 tumor suppressor by protein-protein interactions and phosphorylation.
Int. J. Cancer
PUBLISHED: 06-11-2013
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The deleted in liver cancer 1 (DLC1) tumor suppressor is an important RhoGTP activating protein (RhoGAP) that plays a crucial role in many types of human cancers. Small GTPases regulate normal cellular processes but aberrant expression and activation of GTPases contribute to tumorigenesis. RhoGAP suppresses Rho activity. DLC1s RhoGAP activity and the focal adhesion localization are critical to the tumor suppressor functions of DLC1. Frequent DLC1 underexpression is commonly seen in human cancers and has been ascribed to genomic deletion and epigenetic inactivation. Somatic mutation has been shown to deregulate the RhoGAP activity of DLC1. Deregulation of DLC1 in cells results in the elevation of active Rho. Compelling studies of the molecular mechanisms of DLC1 action have identified various interacting partners of DLC1 such as tensins and caveolin-1, and revealed the associated signaling pathways. DLC1 has been shown to be a promiscuous interacting protein. Recent interest has also focused on the phosphorylation of DLC1. The upstream kinases such as PKA, PKB/Akt and PKC, and the effects of phosphorylation on the biological activities of DLC1 have been demonstrated. Although DLC1 is a RhoGAP, RhoGAP-independent pathways have been involved via its interacting partners and upon phosphorylation regulation. Recent studies of DLC1 point to the complexity of the signaling pathways it regulates. This review summarizes the current understanding of the interacting potentials of DLC1 and phosphorylation of DLC1.
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Sex hormone binding globulin and sex steroids among premenopausal women in the diabetes prevention program.
J. Clin. Endocrinol. Metab.
PUBLISHED: 05-24-2013
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It is unknown whether intensive lifestyle modification (ILS) or metformin changes sex steroids among premenopausal women without a history of polycystic ovarian syndrome (PCOS).
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A pilot randomized study to assess immunogenicity, reactogenicity, safety and tolerability of two human papillomavirus vaccines administered intramuscularly and intradermally to females aged 18-26 years.
Vaccine
PUBLISHED: 05-06-2013
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Intradermal administration of human papillomavirus (HPV) vaccines could be dose-sparing and cost-saving. This pilot randomized study assessed Cervarix(®) and Gardasil(®) administered either intramuscularly or intradermally, in different doses (full-dose or reduced to 20%) by different methods (needle and syringe or PharmaJet needle-free jet injection device). Following an initial reactogenicity study of 10 male subjects, sexually naïve women aged 18-26 years were randomized to the eight study groups to receive vaccine at 0, 2 and 6 months. 42 female subjects were enrolled and complete data were available for 40 subjects. Intradermal administration of either vaccine raised no safety concerns but was more reactogenic than intramuscular administration, although still tolerable. All subjects demonstrated a seroconversion (titre?1:320) by Day 95. Further evaluation of intradermal HPV vaccination and its potential for cost reduction in resource poor settings is warranted.
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A putative terpene cyclase, vir4, is responsible for the biosynthesis of volatile terpene compounds in the biocontrol fungus Trichoderma virens.
Fungal Genet. Biol.
PUBLISHED: 05-02-2013
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A putative terpene cyclase vir4, which is a member of a secondary metabolite cluster, has been deleted in Trichoderma virens to determine its function. The deletion mutants were compared for volatile production with the wild-type as well as two other Trichoderma spp. This gene cluster was originally predicted to function in the synthesis of viridin and viridiol. However, the experimental evidence demonstrates that this gene cluster is involved in the synthesis of volatile terpene compounds. The entire vir4-containing gene cluster is absent in two other species of Trichoderma, T. atroviride and T. reesei. Neither of these two species synthesizes volatile terpenes associated with this cluster in T. virens. We have thus identified a novel class of volatile fungal sesquiterpenes as well as the gene cluster involved in their biosynthesis.
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Intermittent versus continuous erlotinib with concomitant modified "XELOX" (q3W) in first-line treatment of metastatic colorectal cancer: correlation with serum amphiregulin and transforming growth factor alpha.
Cancer
PUBLISHED: 04-25-2013
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This study evaluated the activity of 2 schedules of erlotinib in combination with chemotherapy, and the prognostic significance of serum amphiregulin (AREG) and transforming growth factor alpha (TGFa) in metastatic colorectal cancer.
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Performance of serum ?-fetoprotein levels in the diagnosis of hepatocellular carcinoma in patients with a hepatic mass.
HPB (Oxford)
PUBLISHED: 03-21-2013
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The role of serum ?-fetoprotein (AFP) measurements in the diagnosis of hepatocellular carcinoma (HCC) remains controversial. Some guidelines have advised against the use of AFP in the diagnosis of HCC. This study was conducted to evaluate the performance of AFP in the diagnosis of HCC, and to identify the optimal cut-off value of serum AFP in the diagnosis of HCC in patients with a hepatic mass.
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Pathologic complete response after preoperative anti-HER2 therapy correlates with alterations in PTEN, FOXO, phosphorylated Stat5, and autophagy protein signaling.
BMC Res Notes
PUBLISHED: 03-14-2013
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To define protein molecular characteristics of tumor cells prior to, and immediately following, preoperative human epidermal growth factor receptor 2 (HER2)-targeted therapy that correlate with pathologic complete response (pCR) or non response (no pCR) to preoperative HER2-directed therapy and chemotherapy.
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Predictors of radiolucent foreign body aspiration.
J. Pediatr. Surg.
PUBLISHED: 03-08-2013
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Children frequently present for suspected foreign body aspiration, many have mild symptoms and/or negative radiographs raising the question of a radiolucent foreign body aspiration.
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Obesity in pregnancy. Part 2: management.
Pract Midwife
PUBLISHED: 02-26-2013
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Obesity is placing a huge burden on healthcare resources and the wellbeing of individuals. The first article in this two part series (October 2012) reviewed the prevalence of obesity in pregnancy and the increased risks for pregnant women to their own and their babies health. Management of obesity during pregnancy also places a large burden on midwifery resources. A renewed focus is needed on achieving a healthy weight for pregnancy to ensure optimal outcomes and reduce risks.
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An electrically reversible switchable surface to control and study early bacterial adhesion dynamics in real-time.
Adv. Mater. Weinheim
PUBLISHED: 02-21-2013
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Bacterial adhesion can be controlled by applying electrical potentials to surfaces incorporating well-spaced negatively charged 11-mercaptoundecanoic acids. When combined with electrochemical surface plasmon resonance, these dynamic surfaces become powerful for monitoring and analysing the passage between reversible and non-reversible cell adhesion, opening new opportunities to advance our understanding of cell adhesion processes.
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Proximal femoral nail versus dynamic hip screw fixation for trochanteric fractures: a meta-analysis of randomized controlled trials.
ScientificWorldJournal
PUBLISHED: 02-19-2013
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The purpose of this meta-analysis was to find out whether the proximal femoral nail was better than the dynamic hip screw in the treatment of trochanteric fractures with respect to operation time, blood transfusion, hospital stay, wound complications, number of reoperation, and mortality rate.
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PKA-induced dimerization of the RhoGAP DLC1 promotes its inhibition of tumorigenesis and metastasis.
Nat Commun
PUBLISHED: 02-14-2013
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Deleted in Liver Cancer 1 (DLC1) is a tumour suppressor that encodes a RhoGTPase-activating protein (RhoGAP) and is frequently inactivated in many human cancers. The RhoGAP activity of DLC1 against Rho signalling is well documented and is strongly associated with the tumour suppressor functions of DLC1. However, the mechanism by which the RhoGAP activity of DLC1 is regulated remains obscure. Here, we report that phosphorylation of DLC1 at Ser549 by cyclic AMP-dependent protein kinase A contributes to enhanced RhoGAP activity and promotes the activation of DLC1, which suppresses hepatoma cell growth, motility and metastasis in both in vitro and in vivo models. Intriguingly, we found that Ser549 phosphorylation induces the dimerization of DLC1 and that inducible dimerization of DLC1 can rescue the tumour suppressive and RhoGAP activities of DLC1 containing a Ser549 deletion. Our study establishes a novel regulatory mechanism for DLC1 RhoGAP activity via dimerization induced by protein kinase A signalling.
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Effects of high-protein versus high-carbohydrate diets on markers of ?-cell function, oxidative stress, lipid peroxidation, proinflammatory cytokines, and adipokines in obese, premenopausal women without diabetes: a randomized controlled trial.
Diabetes Care
PUBLISHED: 02-12-2013
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To study the effects of high-protein versus high-carbohydrate diets on various metabolic end points (glucoregulation, oxidative stress [dichlorofluorescein], lipid peroxidation [malondialdehyde], proinflammatory cytokines [tumor necrosis factor-? and interleukin-6], adipokines, and resting energy expenditure [REE]) with high protein-low carbohydrate (HP) and high carbohydrate-low protein (HC) diets at baseline and after 6 months of dietary intervention.
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Enhanced gene delivery by chitosan-disulfide-conjugated LMW-PEI for facilitating osteogenic differentiation.
Acta Biomater
PUBLISHED: 01-25-2013
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Chitosan-disulfide-conjugated LMW-PEI (CS-ss-PEI) was designed to combine the biocompatibility of chitosan and the gene delivery ability of polyethylenimine (PEI) using bio-reducible disulfide for bone morphogenetic protein (BMP2) gene delivery in mediating osteogenic differentiation. It was prepared by conjugating low molecular weight PEI (LMW-PEI) to chitosan through oxidization of thiols introduced for the formation of disulfide linkage. The structure, molecular weight and buffer capacity were characterized by Fourier transform infrared (FTIR), light scattering and acid-base titration, respectively. The reduction in molecular weight of CS-ss-PEI by the reducing agent indicated its bio-reducible property. With the increment in the LMW-PEI component, the copolymer showed increased DNA binding ability and formed denser nanocomplexes. CS-ss-PEI exhibited low cytotoxicity in COS-1, HepG2 and 293T cells over the different weight ratios. The transfection efficiency of CS-ss-PEI4 was significantly higher than that of PEI 25k and comparable with Lipofectamine in mediating luciferase expression. Its application for BMP2 gene delivery was confirmed in C2C12 cells by BMP2 expression. For inducing in vitro osteogenic differentiation, CS-ss-PEI4 mediated BMP2 gene delivery showed a stronger effect in MG-63 osteoblast cells and stem cells in terms of alkaline phosphatase activity and mineralization compared with PEI25k and Lipofectamine. This study provides a potential gene delivery system for orthopedic-related disease.
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Substituted 4-(thiazol-5-yl)-2-(phenylamino)pyrimidines are highly active CDK9 inhibitors: synthesis, X-ray crystal structures, structure-activity relationship, and anticancer activities.
J. Med. Chem.
PUBLISHED: 01-25-2013
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Cancer cells often have a high demand for antiapoptotic proteins in order to resist programmed cell death. CDK9 inhibition selectively targets survival proteins and reinstates apoptosis in cancer cells. We designed a series of 4-thiazol-2-anilinopyrimidine derivatives with functional groups attached to the C5-position of the pyrimidine or to the C4-thiazol moiety and investigated their effects on CDK9 potency and selectivity. One of the most selective compounds, 12u inhibits CDK9 with IC(50) = 7 nM and shows over 80-fold selectivity for CDK9 versus CDK2. X-ray crystal structures of 12u bound to CDK9 and CDK2 provide insights into the binding modes. This work, together with crystal structures of selected inhibitors in complex with both enzymes described in a companion paper, (34) provides a rationale for the observed SAR. 12u demonstrates potent anticancer activity against primary chronic lymphocytic leukemia cells with a therapeutic window 31- and 107-fold over those of normal B- and T-cells.
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A biomechanical study comparing helical blade with screw design for sliding hip fixations of unstable intertrochanteric fractures.
ScientificWorldJournal
PUBLISHED: 01-13-2013
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Dynamic hip screw (DHS) is a well-established conventional implant for treating intertrochanteric fracture. However, revision surgery sometimes still occurs due to the cutting out of implants. A helical blade instead of threaded screw (DHS blade) was designed to improve the fixation power of the osteoporotic intertrochanteric fracture. In this study, the biomechanical properties of DHS blade compared to the conventional DHS were evaluated using an unstable AO/OTA 31-A2 intertrochanteric fracture model. Fifty synthetic proximal femoral bone models with such configuration were fixed with DHS and DHS blade in five different positions: centre-centre (CC), superior-centre (SC), inferior-center (IC), centre-anterior (CA), and centre-posterior (CP). All models had undergone mechanical compression test, and the vertical and rotational displacements were recorded. The results showed that DHS blade had less vertical or rotational displacement than the conventional DHS in CC, CA, and IC positions. The greatest vertical and rotational displacements were found at CP position in both groups. Overall speaking, DHS blade was superior in resisting vertical or rotational displacement in comparison to conventional DHS, and the centre-posterior position had the poorest performance in both groups.
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Repair of large osteochondral defects in a beagle model with a novel type I collagen/glycosaminoglycan-porous titanium biphasic scaffold.
Mater Sci Eng C Mater Biol Appl
PUBLISHED: 01-10-2013
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The limited repair potential of articular cartilage, which hardly heals after injury or debilitating osteoarthritis, is a clinical challenge. The aim of this work was to develop a novel type I collagen (Col)/glycosaminoglycan (GAGs)-porous titanium biphasic scaffold (CGT) and verify its ability to repair osteochondral defects in an animal model with bone marrow stem cells (bMSCs) in the chondral phase. The biphasic scaffold was composed of Col/GAGs as chondral phasic and porous titanium as subchondral phasic. Twenty-four full-thickness defects through the articular cartilage and into the subchondral bone were prepared by drilling into the surface of the femoral patellar groove. Animals were assigned to one of the three groups: 1) CGT with bMSCs (CGTM), 2) only CGT, and 3) no implantation (control). The defect areas were examined grossly, histologically and by micro-CT. The most satisfied cartilage repairing result was in the CGTM group, while CGT alone was better than the control group. Abundant subchondral bone formation was observed in the CGTM and CGT groups but not the control group. Our findings demonstrate that a composite based on a novel biphasic scaffold combined with bMSCs shows a high potential to repair large osteochondral defects in a canine model.
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Ghost publications in the pediatric surgery match.
J. Surg. Res.
PUBLISHED: 01-08-2013
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Pediatric surgery fellowship is considered one of the most competitive subspecialties in medicine. With fierce competition increasing the stakes, publications and first authorship are paramount to the success rate of matching. We analyzed Electronic Residency Application Service applications for verification of authorship to determine rate of misrepresentation.
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Impulsivity is associated with treatment non-completion in cocaine- and methamphetamine-dependent patients but differs in nature as a function of stimulant-dependence diagnosis.
J Subst Abuse Treat
PUBLISHED: 01-08-2013
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Greater impulsivity, assessed by the Barratt Impulsiveness Scale-11 (BIS-11) and Stroop interference scores, has been associated with treatment completion in cocaine-dependent patients. This study evaluated the relationships among impulsivity, stimulant-dependence diagnosis, and treatment completion. Six sites evaluating 12-step facilitation for stimulant abusers obtained the BIS-11 and Stroop from 182 methamphetamine- and/or cocaine-dependent participants. Methamphetamine-dependent, relative to cocaine-dependent, participants evidenced significantly greater BIS-11 non-planning and total scores. There was a trend for poorer response inhibition, measured by the Stroop, in cocaine-dependent, relative to methamphetamine-dependent, participants. Accounting for other factors related to treatment completion, BIS-11 motor score, assessing the tendency to act without thinking, predicted treatment completion for both cocaine-dependent and methamphetamine-dependent patients. These results suggest that methamphetamine-dependent and cocaine-dependent patients may have different impulsivity profiles but that the BIS-11 may be useful in identifying both methamphetamine-dependent and cocaine-dependent patients who are at risk for treatment non-completion.
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Pathological fracture as the presenting feature in pediatric osteosarcoma.
Pediatr Blood Cancer
PUBLISHED: 01-03-2013
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Pathological fracture is an uncommon presentation in patients with long bone osteosarcoma.
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Plasma high sensitivity troponin T levels in adult survivors of childhood leukaemias: determinants and associations with cardiac function.
PLoS ONE
PUBLISHED: 01-01-2013
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We sought to quantify plasma high sensitivity cardiac troponin (hs-cTnT) levels, their determinants, and their associations with left ventricular (LV) myocardial deformation in adult survivors of childhood acute leukaemias.
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Is there a risk of suburban transmission of malaria in Selangor, Malaysia?
PLoS ONE
PUBLISHED: 01-01-2013
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The suburban transmission of malaria in Selangor, Malaysias most developed and populous state still remains a concern for public health in this region. Despite much successful control efforts directed at its reduction, sporadic cases, mostly brought in by foreigners have continued to occur. In addition, cases of simian malaria caused by Plasmodium knowlesi, some with fatal outcome have caused grave concern to health workers. The aim of this study was to investigate the possibility of local malaria transmission in suburban regions of Selangor, which are adjacent to secondary rainforests.
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Eating your words: getting the right messages across.
Pract Midwife
PUBLISHED: 12-03-2011
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Routine visits to primary care settings give health professionals a valuable opportunity to discuss sexual health with women, but may also be a first step in discussing a pregnancy; planned or otherwise. Since nutrition plays a vital role in any healthy pregnancy, its a golden opportunity to give advice about good nutrition--both for the expectant mum and for her growing family--to ensure a safe and healthy pregnancy. Dr Frankie Phillips here provides plenty of information about what constitutes a healthy diet during pre-conception and pregnancy. This article discusses the key components of advice regarding nutrition and food safety for pregnant women in the UK.
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Second malignant neoplasms in childhood cancer survivors in a tertiary paediatric oncology centre in Hong Kong, China.
Chin. Med. J.
PUBLISHED: 11-16-2011
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Childhood cancer survivors were at risk of development of second malignant neoplasms. The aim of this study is to evaluate the incidence, risk factors and outcome of second malignant neoplasms in childhood cancer survivors in a tertiary paediatric oncology centre in Hong Kong, China.
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Reproducible fabrication of robust, renewable vertically aligned multiwalled carbon nanotube/epoxy composite electrodes.
Anal. Chem.
PUBLISHED: 10-05-2011
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We describe the reproducible fabrication of robust, vertically aligned multiwalled carbon nanotube (VACNT)/epoxy composite electrodes. The electrodes are characterized by cyclic voltammetry, impedance spectroscopy, and scanning electron and atomic force microscopies. Low background currents are obtained at the electrodes, and common redox probe molecules and NADH show excellent voltammetric behavior. When electrode performance deteriorates due to fouling, the electrode surfaces can be reproducibly renewed by mechanical polishing followed by O(2) plasma treatment. The electrochemical performance of the electrodes is maintained after more than 100 cycles of use and renewal.
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Development of self-immolative dendrimers for drug delivery and sensing.
J Control Release
PUBLISHED: 09-27-2011
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Traditional dendrimers possess unique cascade-branched structural properties that allow for multivalent modifications with drug cargos, targeting/delivery agents and imaging tools. In addition to multivalency, the dendrimers macromolecular size also brings about the enhanced permeability and retention (EPR) effect, which makes it an attracting agent for drug delivery and biosensing. Similar to other macromolecules, therapeutic application of dendrimers in the human body faces practical challenges such as target specificity and toxicity. The latter represents a substantial issue due to the dendrimers unnatural chemical structure and relatively large size, which prohibit its in vivo degradation and excretion from the body. To date, a class of self-immolative dendrimers has been developed to overcome these obstacles, which takes advantage of its unique structural backbone to allow for cascade decompositions upon a simple triggering event. The specific drug release can be achieved through a careful design of the trigger, and as a result of the fragmentation, the generated small molecules are either biodegradable or easily excreted from the body. Though still at a preliminary stage, the development of this novel approach represents an important direction in nanoparticle-mediated drug delivery and sensor design, thereby opening up an insightful frontier of dendrimer based applications.
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Early Experience in Implementation of a Learning Assessment Toolkit in the AOTrauma Geriatric Fracture Course.
Geriatr Orthop Surg Rehabil
PUBLISHED: 09-01-2011
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Surgical education is continually expanding to encompass new techniques and technologies. It is vital that educational activity is directed at gaps in knowledge and ability to improve the quality of learning.
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A study of circulating interleukin 10 in prognostication of unresectable hepatocellular carcinoma.
Cancer
PUBLISHED: 08-30-2011
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The level of circulating interleukin 10 (IL-10) is elevated in a proportion of patients with hepatocellular carcinoma (HCC). The objective of the current study was to evaluate the prognostic significance of serum the IL-10 level in patients with unresectable HCC.
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The use of high-frequency oscillating ventilation to facilitate stability during neonatal thoracoscopic operations.
J Laparoendosc Adv Surg Tech A
PUBLISHED: 08-22-2011
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Thoracoscopy has become a surgical option for the repair of esophageal atresia (EA) and congenital diaphragmatic hernia (CDH). Insufflation of carbon dioxide combined with one lung ventilation creates an anesthetic challenge to control acidosis and maintain oxygenation while allowing optimal operative exposure. We have overcome these issues by utilizing the high-frequency oscillating ventilator (HFOV) and report our early experience.
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.