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Find video protocols related to scientific articles indexed in Pubmed.
A Cell-Based Strategy to Assess Intrinsic Inhibition Efficiencies of HIV-1 Reverse Transcriptase Inhibitors.
Antimicrob. Agents Chemother.
PUBLISHED: 11-19-2014
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During HIV-1 reverse transcription, there are increasing opportunities for nucleos(t)ide (NRTI) or non-nucleoside (NNRTI) reverse transcriptase inhibitors to stop elongation of the nascent viral DNA. In addition, RT inhibitors appear to influence the kinetics of vDNA synthesis differently. While cell-free kinetic inhibition constants have provided detailed mechanistic insight, these assays are dependent on experimental conditions that may not mimic the cellular milieu. Here we describe a novel cell-based strategy to provide a measure of the intrinsic inhibition efficiencies of clinically relevant RT inhibitors on a per-stop-site basis. To better compare inhibition efficiencies among HIV-1 RT inhibitors that can stop reverse transcription at any number of different stop sites, their basic probability, p, of getting stopped at any potential stop site was determined. A relationship between qPCR-derived EC50 values and this basic probability, p, enabled determination of p by successive approximation. On a per-stop-site basis, tenofovir (TFV) exhibited 1.4-fold greater inhibition efficiency than emtricitabine (FTC), and as a class, both NRTIs exhibited an 8- to 11-fold greater efficiency than efavirenz (EFV). However, as more potential stops-sites were considered, the probability of reverse transcription failing to reach the end of the template approached equivalence between both classes of RT inhibitors. Overall, this novel strategy provides a quantitative measure of the intrinsic inhibition efficiencies of RT inhibitors in the natural cellular milieu and thus may further understanding of drug efficacy. This approach also has applicability for understanding the impact of viral polymerase-based inhibitors (alone or in combination) in other virus systems.
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Comparison of continuous versus pulsed ultraviolet light emitting diode use for the inactivation of Bacillus globigii spores.
Water Sci. Technol.
PUBLISHED: 11-18-2014
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Light emitting diodes (LEDs) in the ultraviolet (UV) range offer a promising alternative for the disinfection of water. LEDs have many advantages over conventional UV lamps but there are concerns related to the operating life of the LED lamps. In this project Bacillus globigii was inactivated using UV LED technology. The experimental strategy included using pulsed ultraviolet (PUV) output rather than continuous UV (CUV) current in order to reduce the power requirements and extend the life of the lamps. The kinetic profiles for CUV experiments reached 6-log inactivation faster than PUV at 9.1% duty cycle (approx. 840 vs. 5,000 s) but the PUV required lower fluence (365 vs. 665 J/m(2)). In addition, the inactivation rate constants associated with PUV were generally higher than those of CUV (4.6-5.1 vs. 3.6-4.4 m(2)/J), which supports the notion that high energy bursts are more effective at causing cellular damage. Multi-target kinetics applied to most of the kinetic observations and tailing effects were generally observed. PUV LED appears to have potential to extend the lifetime of the LEDs for inactivation of spore-forming pathogens.
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A Physical Activity Intervention to Treat the Frailty Syndrome in Older Persons-Results From the LIFE-P Study.
J. Gerontol. A Biol. Sci. Med. Sci.
PUBLISHED: 11-13-2014
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The frailty syndrome is as a well-established condition of risk for disability. Aim of the study is to explore whether a physical activity (PA) intervention can reduce prevalence and severity of frailty in a community-dwelling elders at risk of disability.
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In Vitro Resistance Selection with Doravirine (MK-1439): a Novel Non-Nucleoside Reverse Transcriptase Inhibitor with Distinct Mutation Development Pathways.
Antimicrob. Agents Chemother.
PUBLISHED: 11-12-2014
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Doravirine (DOR, formerly known as MK-1439) is a human immunodeficiency type 1 virus (HIV-1) non-nucleoside reverse transcriptase inhibitor (NNRTI), which is currently in Ph 2b clinical trials. In vitro resistance selection was conducted with DOR, rilpivirine (RPV), and efavirine (EFV) in subtype B virus (MT4-GFP cells) as well as subtypes A and C viruses (MT4-GFP/CCR5 cells) under low multiplicity of infection (moi) conditions in 96-well format. The resistance selection was performed with escalating concentration of the NNRTIs from 1x EC50 to 1000x EC50 in the presence of 10% FBS. In the resistance selection with DOR in subtype B virus, V106A mutant led two mutation pathways followed by the emergence separately of either F227L or L234I. In the resistance selection in subtype A and C viruses, similar mutation development pathways were detected, which V106A or V106M mutant was also the starting virus in the pathways. Mutants that are commonly associated with RPV and EFV in the clinical settings were also identified in this in vitro resistance selection study in subtype B virus, such as E138K and K103N, respectively. The susceptibility of subtype B mutant viruses selected by DOR, RPV, and EFV to NNRTIs was evaluated. Results suggest that mutant viruses selected by DOR are susceptible to RPV and EFV, and mutants selected by RPV and EFV are susceptible to DOR. When the replication capacity of V106A mutant was evaluated versus wild-type (WT) virus, the mutant virus displayed 4-fold reduction in fitness compared with WT virus.
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Derivatives of mesoxalic acid block translocation of HIV-1 reverse transcriptase.
J. Biol. Chem.
PUBLISHED: 10-31-2014
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The pyrophosphate mimic and broad spectrum antiviral phosphonoformic acid (PFA, forscarnet) was shown to freeze the pre-translocational state of the reverse transcriptase (RT) complex of the human immunodeficiency virus type 1 (HIV-1). However, PFA lacks a specificity domain, which is seen as a major reason for toxic side effects associated with the clinical use of this drug. Here we studied the mechanism of inhibition of HIV-1 RT by the 4-chlorophenylhydrazone of mesoxalic acid (CPHM), and demonstrate that this compound also blocks RT translocation. Hot spots for inhibition with PFA or CPHM occur at template positions with a bias toward pre-translocation. Mutations at active site residue D185 compromise binding of both compounds. Moreover, divalent metal ions are required for the formation of ternary complexes with either of the two compounds. However, CPHM contains both an anchor domain that likely interacts with the catalytic metal ions and a specificity domain. Thus, although the inhibitor binding sites may partly overlap, they are not identical. The K65R mutation in HIV-1 RT, which reduces affinity to PFA, increases affinity to CPHM. Details with respect to the binding sites of the two inhibitors are provided on the basis of mutagenesis studies, structure activity relationship analyses with newly designed CPHM derivatives, and in silico docking experiments. Together, these findings validate the pre-translocated complex of HIV-1 RT as a specific target for the development of novel classes of RT inhibitors.
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Week 144 resistance analysis of elvitegravir/cobicistat/emtricitabine/tenofovir DF versus atazanavir+ritonavir+emtricitabine/tenofovir DF in antiretroviral-naïve patients.
HIV Clin Trials
PUBLISHED: 10-29-2014
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To describe baseline and emergent HIV-1 resistance to elvitegravir/ cobicistat/emtricitabine/tenofovir DF (EVG/COBI/FTC/TDF) and ritonavir-boosted atazanavir/emtricitabine/tenofovir DF (ATV+RTV+FTC/TDF) in HIV-1-infected, treatment-naïve subjects through 144 weeks.
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Spatial Patterns of Structural Brain Changes in Type 2 Diabetic Patients and Their Longitudinal Progression With Intensive Control of Blood Glucose.
Diabetes Care
PUBLISHED: 10-23-2014
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Understanding the effect of diabetes as well as of alternative treatment strategies on cerebral structure is critical for the development of targeted interventions against accelerated neurodegeneration in type 2 diabetes. We investigated whether diabetes characteristics were associated with spatially specific patterns of brain changes and whether those patterns were affected by intensive versus standard glycemic treatment.
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Week 144 resistance analysis of elvitegravir/cobicistat/emtricitabine/tenofovir DF versus efavirenz/emtricitabine/tenofovir DF in antiretroviral-naive patients.
Antivir. Ther. (Lond.)
PUBLISHED: 10-05-2014
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Describe baseline and emergent resistance to elvitegravir/cobicistat/ emtricitabine/tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF) versus efavirenz (EFV)/FTC/TDF in HIV-1 infected antiretroviral-naïve adults through 144 weeks from the randomized, ongoing, phase 3 study GS-US-236-0102.
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Effect of Hypoglycemia on Brain Structure in People With Type 2 Diabetes: Epidemiological Analysis of the ACCORD-MIND MRI Trial.
Diabetes Care
PUBLISHED: 09-29-2014
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The effect of hypoglycemia related to treatment of type 2 diabetes mellitus (T2DM) on brain structure remains unclear. We aimed to assess whether symptomatic severe hypoglycemia is associated with brain atrophy and/or white matter abnormalities.
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Infrequent Development of Resistance in Genotype 1-6 Hepatitis C Virus-Infected Subjects Treated With Sofosbuvir in Phase 2 and 3 Clinical Trials.
Clin. Infect. Dis.
PUBLISHED: 09-28-2014
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?Sofosbuvir is a chain-terminating nucleotide analogue inhibitor of the hepatitis C virus (HCV) NS5B RNA polymerase that is efficacious in subjects with HCV genotype 1-6 infection. Sofosbuvir resistance is primarily conferred by the S282T substitution in NS5B.
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Development of an updated tensile neck injury criterion.
Aviat Space Environ Med
PUBLISHED: 09-24-2014
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Ejection neck safety remains a concern in military aviation with the growing use of helmet mounted displays (HMDs) worn for entire mission durations. The original USAF tensile neck injury criterion proposed by Carter et al. (4) is updated and an injury protection limit for tensile loading is presented to evaluate escape system and HMD safety.
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A preliminary comparison of myoelectric and cyclic control of an implanted neuroprosthesis to modulate gait speed in incomplete SCI.
J Spinal Cord Med
PUBLISHED: 09-23-2014
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Objective Explore whether electromyography (EMG) control of electrical stimulation for walking after incomplete spinal cord injury (SCI) can affect ability to modulate speed and alters gait spatial-temporal parameters compared to cyclic repetition of pre-programmed stimulation. Design Single case study with subject acting as own concurrent control. Setting Hospital-based biomechanics laboratory. Participants Single subject with C6 AIS D SCI using an implanted neuroprosthesis for walking. Interventions Lower extremity muscle activation via an implanted system with two different control methods: (1) pre-programmed pattern of stimulation, and (2) EMG-controlled stimulation based on signals from the gastrocnemius and quadriceps. Outcome measures Gait speed, distance, and subjective rating of difficulty during 2-minute walks. Range of walking speeds and associated cadences, stride lengths, stride times, and double support times during quantitative gait analysis. Results EMG control resulted in statistically significant increases in both walking speed and distance (P < 0.001) over cyclic stimulation during 2-minute walks. Maximum walking speed with EMG control (0.48 m/second) was significantly (P < 0.001) faster than the fastest automatic pattern (0.39 m/second), with increased cadence and decreased stride and double support times (P < 0.000) but no change in stride length (z = -0.085; P = 0.932). The slowest walking with EMG control (0.25 m/second) was virtually indistinguishable from the slowest with automatic cycling (z = -0.239; P = 0.811). Conclusion EMG control can increase the ability to modulate comfortable walking speed over pre-programmed cyclic stimulation. While control methods did not differ at the lowest speed, EMG-triggered stimulation allowed significantly faster walking than cyclic stimulation. The expanded range of available walking speeds could permit users to better avoid obstacles and naturally adapt to various environments. Further research is required to definitively determine the robustness, generalizability, and functional implications of these results.
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Spatial disorientation mishap trends in the U.S. Air force 1993-2013.
Aviat Space Environ Med
PUBLISHED: 09-09-2014
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Spatial disorientation is a significant factor in a large percentage of military Class A aviation mishaps. While previous studies have analyzed accident statistics, they often suffer from methodological flaws, which lead to questionable conclusions.
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The Cross-Sectional and Longitudinal Associations of Diabetic Retinopathy With Cognitive Function and Brain MRI Findings: The Action to Control Cardiovascular Risk in Diabetes (ACCORD) Trial.
Diabetes Care
PUBLISHED: 09-05-2014
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Longitudinal evidence linking diabetic retinopathy with changes in brain structure and cognition is sparse. We used data from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial to determine whether diabetic retinopathy at baseline predicted changes in brain structure or cognition 40 months later.
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Clinical and In Vitro Resistance to GS-9669, a Thumb Site II Nonnucleoside Inhibitor of the Hepatitis C Virus NS5B Polymerase.
Antimicrob. Agents Chemother.
PUBLISHED: 08-25-2014
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Treatment with GS-9669, a novel nonnucleoside inhibitor (site II) of hepatitis C virus (HCV) nonstructural 5B (NS5B) polymerase, resulted in significant antiviral activity in HCV genotype (GT) 1 patients dosed at 50 and 500 mg once daily (QD) and at 50, 100, and 500 mg twice daily (BID) for 3 days. This report characterizes the virologic resistance to GS-9669 in vitro and in GT1 HCV-infected patients from a phase I clinical study. An in vitro resistance selection study with GS-9669 revealed substitutions at several NS5B residues that conferred resistance. The M423 variants were selected at low drug concentrations (5× the 50% effective concentration [EC50]), and the L419, R422, and I482 variants were selected at higher drug concentrations (20× the EC50). During the phase I clinical study, substitutions at NS5B residues 419, 422, and 486 were the predominant changes associated with GS-9669 monotherapy. Substitutions at position 423 were observed only in GT1a patients in the low-dose groups (50 and 100 mg BID). Interestingly, four HCV patients had substitutions at position 423 at baseline. Consistent with the low resistance level at this position, three patients with M423I or M423V at baseline achieved >2-log10 reductions of HCV RNA when treated with 100 mg BID or with 500 mg QD or BID of GS-9669. The fourth patient, who had the M423V substitution at baseline, had a 4.4-log10 reduction of HCV RNA with 500 mg BID of GS-9669. Phenotypic analyses demonstrated that the viral isolates with multiple GS-9669 resistance-associated variants have reduced susceptibility to GS-9669 and lomibuvir (VX-222) but are not cross-resistant to other classes of HCV inhibitors. (This study has been registered at ClinicalTrials.gov under registration no. NCT01431898.).
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Enhanced intracellular translocation and biodistribution of gold nanoparticles functionalized with a cell-penetrating peptide (VG-21) from vesicular stomatitis virus.
Biomaterials
PUBLISHED: 08-22-2014
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Reduced toxicity and ease of modification make gold nanoparticles (GNPs) suitable for targeted delivery, bioimaging and theranostics by conjugating cell-penetrating peptides (CPPs). This study presents the biodistribution and enhanced intracellular uptake of GNPs functionalized with VG-21, a CPP derived from vesicular stomatitis virus glycoprotein (G). Cell penetrating efficiency of VG-21 was demonstrated using CellPPD web server, conjugated to GNPs and were characterized using, UV-visible and FTIR spectroscopy, transmission electron microscopy, dynamic light scattering and zeta potential. Uptake of VG-21 functionalized GNPs (fGNPs) was tested in eukaryotic cell lines, HEp-2, HeLa, Vero and Cos-7, using flow cytometry, fluorescence and transmission electron microscopy (TEM), and inductively coupled plasmon optical emission spectroscopy (ICP-OES). The effects of nanoparticles on stress and toxicity related genes were studied in HEp-2 cells. Cytokine response to fGNPs was studied in vitro and in vivo. Biodistribution of nanoparticles was studied in BALB/c mice using TEM and ICP-OES. VG-21, GNPs and fGNPs had little to no effect on cell viability. Upon exposure to fGNPs, HEp-2 cells revealed minimal down regulation of stress response genes. fGNPs displayed higher uptake than GNPs in all cell lines with highest internalization by HEp-2, HeLa and Cos-7 cells, in endocytotic vesicles and nuclei. Cytokine ELISA showed that mouse J774 cells exposed to fGNPs produced less IL-6 than did GNP-treated macrophage cells, whereas TNF-? levels were low in both treatment groups. Biodistribution studies in BALB/c mice revealed higher accumulation of fGNPs than GNPs in the liver and spleen. Histopathological analyses showed that fGNP-treated mice accumulated 35 ng/mg tissue and 20 ng/mg tissue gold in spleen and liver respectively, without any adverse effects. Likewise, serum cytokines were low in both GNP- and fGNP-treated mice. Thus, VG-21-conjugated GNPs have enhanced cellular internalization and are suitable for various biomedical applications as nano-conjugates.
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Development of a sensitive amplified luminescent proximity homogeneous assay to monitor the interactions between pTEFb and Tat.
Anal. Biochem.
PUBLISHED: 08-14-2014
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The viral transactivator protein (Tat) plays an essential role in the replication of human immunodeficiency type 1 virus (HIV-1) by recruiting the host positive transcription elongation factor (pTEFb) to the RNA polymerase II transcription machinery to enable an efficient HIV-1 RNA elongation process. Blockade of the interaction between Tat and pTEFb represents a novel strategy for developing a new class of antiviral agents. In this study, we developed a homogeneous assay in AlphaLISA (amplified luminescent proximity homogeneous assay) format using His-tagged pTEFb and biotinylated Tat to monitor the interaction between Tat and pTEFb. On optimizing the assay conditions, the signal-to-background ratio was found to be greater than 10-fold. The assay was validated with untagged Tat and peptides known to compete with Tat for pTEFb binding. The Z' of the assay is greater than 0.5, indicating that the assay is robust and can be easily adapted to a high-throughput screening format. Furthermore, the affinity between Tat and pTEFb was determined to be approximately 20pM, and only 7% of purified Tat was found to be active in forming tertiary complex with pTEFb. Development of this assay should facilitate the discovery of a new class of antiviral agents providing HIV-1 patients with broader treatment choices.
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Contribution of human immunodeficiency virus type 1 minority variants to reduced drug susceptibility in patients on an integrase strand transfer inhibitor-based therapy.
PLoS ONE
PUBLISHED: 08-11-2014
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The role of HIV-1 minority variants on transmission, pathogenesis, and virologic failure to antiretroviral regimens has been explored; however, most studies of low-level HIV-1 drug-resistant variants have focused in single target regions. Here we used a novel HIV-1 genotypic assay based on deep sequencing, DEEPGEN (Gibson et al 2014 Antimicrob Agents Chemother 58?2167) to simultaneously analyze the presence of minority variants carrying mutations associated with reduced susceptibility to protease (PR), reverse transcriptase (RT), and integrase strand transfer integrase inhibitors (INSTIs), as well as HIV-1 coreceptor tropism. gag-p2/NCp7/p1/p6/pol-PR/RT/INT and env/C2V3 PCR products were obtained from twelve heavily treatment-experienced patients experiencing virologic failure while participating in a 48-week dose-ranging study of elvitegravir (GS-US-183-0105). Deep sequencing results were compared with (i) virological response to treatment, (ii) genotyping based on population sequencing, (iii) phenotyping data using PhenoSense and VIRALARTS, and (iv) HIV-1 coreceptor tropism based on the phenotypic test VERITROP. Most patients failed the antiretroviral regimen with numerous pre-existing mutations in the PR and RT, and additionally newly acquired INSTI-resistance mutations as determined by population sequencing (mean 9.4, 5.3, and 1.4 PI- RTI-, and INSTI-resistance mutations, respectively). Interestingly, since DEEPGEN allows the accurate detection of amino acid substitutions at frequencies as low as 1% of the population, a series of additional drug resistance mutations were detected by deep sequencing (mean 2.5, 1.5, and 0.9, respectively). The presence of these low-abundance HIV-1 variants was associated with drug susceptibility, replicative fitness, and coreceptor tropism determined using sensitive phenotypic assays, enhancing the overall burden of resistance to all four antiretroviral drug classes. Further longitudinal studies based on deep sequencing tests will help to clarify (i) the potential impact of minority HIV-1 drug resistant variants in response to antiretroviral therapy and (ii) the importance of the detection of HIV minority variants in the clinical practice.
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Factors Associated with Short- and Long-term Outcomes of Therapy for Crohn's Disease.
Clin. Gastroenterol. Hepatol.
PUBLISHED: 08-06-2014
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Our post-hoc analysis assessed the association of early (at weeks 26-30) clinical, endoscopic, biologic, and pharmacokinetic outcomes with corticosteroid-free remission at week 50 (CSFR50); CSFR50 was observed in 55.2% and 65.4% of patients treated with infliximab, alone or in combination with azathioprine, respectively.
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Effects of intensive glycaemic control on ischaemic heart disease: analysis of data from the randomised, controlled ACCORD trial.
Lancet
PUBLISHED: 08-05-2014
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Hyperglycaemia could substantially increase the risk of ischaemic heart disease in patients with type 2 diabetes. We investigated whether intensive lowering of glucose concentrations affects risk.
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The combined anti-HIV-1 activities of emtricitabine and tenofovir plus the integrase inhibitor elvitegravir or raltegravir show high levels of synergy in vitro.
Antimicrob. Agents Chemother.
PUBLISHED: 08-04-2014
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Highly active antiretroviral therapy (HAART) involves combination treatment with three or more antiretroviral agents. The antiviral effects of combinations of emtricitabine (FTC) plus tenofovir (TFV) plus antiretroviral agents of all the major drug classes were investigated. Combinations of FTC and TFV with a nonnucleoside reverse transcriptase inhibitor (NNRTI) (efavirenz or rilpivirine) or with a protease inhibitor (PI) (atazanavir, lopinavir, or darunavir) showed additive to synergistic anti-HIV-1 activity. FTC-TFV with an HIV-1 integrase strand transfer inhibitor (INSTI) (elvitegravir or raltegravir) showed the strongest synergy. Anti-HIV-1 synergy suggests enhancement of individual anti-HIV-1 activities within cells that may contribute to potent treatment efficacy and open new areas of research into interactions between reverse transcriptase (RT) and integrase inhibitors.
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Sleep-wake disturbances in sedentary community-dwelling elderly adults with functional limitations.
J Am Geriatr Soc
PUBLISHED: 06-02-2014
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To evaluate sleep-wake disturbances in sedentary community-dwelling elderly adults with functional limitations.
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Effect of structured physical activity on prevention of major mobility disability in older adults: the LIFE study randomized clinical trial.
JAMA
PUBLISHED: 05-29-2014
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In older adults reduced mobility is common and is an independent risk factor for morbidity, hospitalization, disability, and mortality. Limited evidence suggests that physical activity may help prevent mobility disability; however, there are no definitive clinical trials examining whether physical activity prevents or delays mobility disability.
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Resistance analyses of integrase strand transfer inhibitors within phase 3 clinical trials of treatment-naive patients.
Viruses
PUBLISHED: 05-23-2014
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The integrase (IN) strand transfer inhibitors (INSTIs), raltegravir (RAL), elvitegravir (EVG) and dolutegravir (DTG), comprise the newest drug class approved for the treatment of HIV-1 infection, which joins the existing classes of reverse transcriptase, protease and binding/entry inhibitors. The efficacy of first-line regimens has attained remarkably high levels, reaching undetectable viral loads in 90% of patients by Week 48; however, there remain patients who require a change in regimen due to adverse events, virologic failure with emergent resistance or other issues of patient management. Large, randomized clinical trials conducted in antiretroviral treatment-naive individuals are required for drug approval in this population in the US, EU and other countries, with the primary endpoint for virologic success at Week 48. However, there are differences in the definition of virologic failure and the evaluation of drug resistance among the trials. This review focuses on the methodology and tabulation of resistance to INSTIs in phase 3 clinical trials of first-line regimens and discusses case studies of resistance.
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Effect of diabetes on brain structure: the action to control cardiovascular risk in diabetes MR imaging baseline data.
Radiology
PUBLISHED: 04-29-2014
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To investigate the association of characteristics of type 2 diabetes mellitus (duration and biochemical severity of diabetes) to brain structure measured on magnetic resonance (MR) images, specifically testing whether more severity in metrics of diabetes is inversely correlated with brain volumes and positively correlated with ischemic lesion volumes.
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Characterization of hepatitis C virus inter-genotypic recombinant strains and associated virologic response to sofosbuvir/ribavirin.
Hepatology
PUBLISHED: 04-24-2014
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To date, inter-genotypic recombinant hepatitis C viruses (HCV) and their treatment outcomes have not been well characterized. This study characterized 12 novel HCV recombinant strains and their response to sofosbuvir in combination with ribavirin (SOF/RBV) treatment. Across the phase II/III studies of sofosbuvir, HCV samples were genotyped using both the Siemens VERSANT® HCV Genotype INNO-LiPA 2.0 assay and NS5B sequencing. Among these patient samples, genotype assignment discordance between the two methods was found in 0.5% of all cases (12/2363) of which all were identified as genotype 2 by INNO-LiPA (12/487=2.5%). HCV full genome sequences were obtained for these 12 samples by a sequence-independent amplification method coupled with next-generation sequencing. HCV full genome sequencing revealed that these viruses were recombinant HCV strains with the 5' part corresponding to genotype 2 and the 3' part corresponding to genotype 1. The recombination breakpoint between genotype 2 and genotype 1 was consistently located within 80 amino acids of the NS2/NS3 junction. Interestingly, one of the recombinant viruses had a 34 amino acid duplication at the location of the recombination breakpoint. Eleven of these 12 patients were treated with a regimen for genotype 2 HCV infection, but responded like they had genotype 1 infection; one patient had received placebo. Conclusion: Twelve new HCV inter-genotypic recombinant genotype 2/1 viruses have been characterized. The antiviral response to a 12-16 week course of SOF/RBV treatment in these patients was more similar to responses among genotype 1 patients than genotype 2 patients, consistent with their genotype 1 NS5B gene. (Hepatology 2014;).
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Patterns of diagnoses among children and young adults with life-limiting conditions: A secondary analysis of a national dataset.
Palliat Med
PUBLISHED: 04-03-2014
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Numbers of children and young people with life-limiting conditions are rising, and increasing lifespans require young adults with life-limiting condition to transit to appropriate adult services.
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Isolated Lactobacillus chronic prosthetic knee infection.
Orthopedics
PUBLISHED: 04-02-2014
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Lactobacillus is a gram-positive rod bacteria found primarily in the gastrointestinal and female genital tracts. Prosthetic infections in implants are being increasingly reported. The authors present a case of a 58-year-old patient with Lactobacillus septic prosthetic knee joint infection. To the authors’ knowledge, this is the first reported case of chronic prosthetic knee infection with isolated Lactobacillus species. Lactobacillus has been most commonly implicated with bacteremia and endocarditis and rarely with pneumonia, meningitis, and endovascular infection, and a vast majority of the cases are reported in immunocompromised patients. In the current case, diabetes mellitus, hepatitis, malnutrition, anemia, and liver failure were comorbid conditions, placing the patient at increased risk of infection. The findings suggest that further case series are necessary to establish the significance of Lactobacillus as an etiologic agent in chronic low-virulence, and potentially vancomycin-resistant, prosthetic joint infection. The need also exists for further research aimed at the risk of prosthetic joint infection with oral intake of certain probiotic foods and supplements. The goal of this case report is to bring to light the potential of this organism to be a cause of subtle chronic prosthetic joint infection.
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Durable change in glycaemic control following intensive management of type 2 diabetes in the ACCORD clinical trial.
Diabetologia
PUBLISHED: 03-29-2014
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We aimed to determine the persistence of glycaemic control 1 year after a limited period of intensive glycaemic management of type 2 diabetes.
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No Resistance to Tenofovir Disoproxil Fumarate Through 96 Weeks of Treatment in Patients With Lamivudine-Resistant Chronic Hepatitis B.
Clin. Gastroenterol. Hepatol.
PUBLISHED: 03-04-2014
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A recent study compared the efficacy of tenofovir disoproxil fumarate (TDF) vs the combination of emtricitabine and TDF (FTC/TDF) in patients with lamivudine-resistant chronic hepatitis B who were treated for as long as 96 weeks. We report findings from resistance analyses conducted for this study.
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The discovery of N-((2H-tetrazol-5-yl)methyl)-4-((R)-1-((5r,8R)-8-(tert-butyl)-3-(3,5-dichlorophenyl)-2-oxo-1,4-diazaspiro[4.5]dec-3-en-1-yl)-4,4-dimethylpentyl)benzamide (SCH 900822): a potent and selective glucagon receptor antagonist.
J. Med. Chem.
PUBLISHED: 02-26-2014
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A novel series of spiroimidazolone-based antagonists of the human glucagon receptor (hGCGR) has been developed. Our efforts have led to compound 1, N-((2H-tetrazol-5-yl)methyl)-4-((R)-1-((5r,8R)-8-(tert-butyl)-3-(3,5-dichlorophenyl)-2-oxo-1,4-diazaspiro[4.5]dec-3-en-1-yl)-4,4-dimethylpentyl)benzamide (SCH 900822), a potent hGCGR antagonist with exceptional selectivity over the human glucagon-like peptide-1 receptor. Oral administration of 1 lowered 24 h nonfasting glucose levels in imprinting control region mice on a high fat diet with diet-induced obesity following single oral doses of 3 and 10 mg/kg. Furthermore, compound 1, when dosed orally, was found to decrease fasting blood glucose at 30 mg/kg in a streptozotocin-treated, diet-induced obesity mouse pharmacodynamic assay and blunt exogenous glucagon-stimulated glucose excursion in prediabetic mice.
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Vitamin and Supplement Use among Old Order Amish: Sex-Specific Prevalence and Associations with Use.
J Acad Nutr Diet
PUBLISHED: 02-21-2014
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Complementary and alternative medicine (CAM) in the form of vitamin and supplement use is increasingly prevalent in the United States. The interplay between CAM use and use of conventional medications is not well studied. We examined this issue in Old Order Amish (OOA), a population lacking several factors known to influence supplement use, whose culture and barriers to conventional medications may result in high rates of supplement use.
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Characterization of HIV-1 drug resistance development through week 48 in antiretroviral naive subjects on rilpivirine/emtricitabine/tenofovir DF or efavirenz/emtricitabine/tenofovir DF in the STaR study (GS-US-264-0110).
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 02-15-2014
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The Single-Tablet Regimen (STaR) study (GS-US-264-0110) is a 96-week phase 3b study evaluating the safety and efficacy of 2 single-tablet regimens, rilpivirine/emtricitabine/tenofovir DF (RPV/FTC/TDF), and efavirenz/emtricitabine/tenofovir DF (EFV/FTC/TDF) in treatment-naive HIV-1-infected subjects.
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Evaluation of HBV DNA decay kinetics in patients containing both rtM204V/I mutant and wild-type HBV subpopulations during tenofovir DF (TDF) monotherapy or combination therapy with emtricitabine (FTC)/TDF.
J. Med. Virol.
PUBLISHED: 02-07-2014
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Tenofovir disoproxil fumarate (TDF) is recommended as treatment for chronic hepatitis B patients harboring lamivudine-associated resistance mutations (LAM-R, rtM204V/I?±?rtL180M). This study evaluated the clinical response of rtM204V and rtM204I subpopulations to TDF by comparing their early viral load decay kinetics to wild-type (WT) subpopulations in chronic hepatitis B patients harboring rtM204V/I prior to initiating TDF or emtricitabine (FTC)/TDF therapy. Allele-specific PCR assays capable of detecting rtM204V or rtM204I subpopulations as low as 0.5% were developed and used to assess patient samples from a Phase 3b study evaluating TDF and FTC/TDF treatment in LAM-R patients. Baseline samples (n?=?280) were quantified for rtM204V/I subpopulations and rtM204V or rtM204I subpopulations were detected in 269/273 (98.5%) baseline samples with a range of 0.7% to >95%. On-treatment analyses were conducted for seventeen patients (TDF, n?=?8; FTC/TDF, n?=?9) that harbored baseline WT and either rtM204V or rtM204I (no rtM204V/I mixtures) and HBV DNA ?1,000?copies/ml at/after week 4. The median change in HBV DNA through week 12 for WT and rtM204V/I subpopulations was similar, -2.64 and -3.30?log10 ?copies/ml, respectively, with no significant difference between TDF and FTC/TDF treatment. In conclusion, rtM204V/I subpopulations demonstrate similar early HBV DNA decline kinetics to WT subpopulations during treatment with either TDF or FTC/TDF. These results demonstrate that TDF is similarly active against both WT and rtM204V/I subpopulations in vivo.
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Phase I/II study of the pharmacokinetics, safety and antiretroviral activity of tenofovir alafenamide, a new prodrug of the HIV reverse transcriptase inhibitor tenofovir, in HIV-infected adults.
J. Antimicrob. Chemother.
PUBLISHED: 02-06-2014
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Tenofovir alafenamide (formerly GS-7340) is a new oral prodrug of tenofovir, a nucleotide analogue that inhibits HIV-1 reverse transcription. Unlike the currently marketed tenofovir prodrug, tenofovir disoproxil fumarate, tenofovir alafenamide is stable in plasma and then rapidly converted into tenofovir once inside cells.
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Comparison of PECARN, CATCH, and CHALICE rules for children with minor head injury: a prospective cohort study.
Ann Emerg Med
PUBLISHED: 01-24-2014
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We evaluate the diagnostic accuracy of clinical decision rules and physician judgment for identifying clinically important traumatic brain injuries in children with minor head injuries presenting to the emergency department.
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Proteomic and genomic studies of non-alcoholic fatty liver disease--clues in the pathogenesis.
World J. Gastroenterol.
PUBLISHED: 01-14-2014
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Non-alcoholic fatty liver disease (NAFLD) is a widely prevalent hepatic disorder that covers wide spectrum of liver pathology. NAFLD is strongly associated with liver inflammation, metabolic hyperlipidaemia and insulin resistance. Frequently, NAFLD has been considered as the hepatic manifestation of metabolic syndrome. The pathophysiology of NAFLD has not been fully elucidated. Some patients can remain in the stage of simple steatosis, which generally is a benign condition; whereas others can develop liver inflammation and progress into non-alcoholic steatohepatitis, fibrosis, cirrhosis and hepatocellular carcinoma. The mechanism behind the progression is still not fully understood. Much ongoing proteomic researches have focused on discovering the unbiased circulating biochemical markers to allow early detection and treatment of NAFLD. Comprehensive genomic studies have also begun to provide new insights into the gene polymorphism to understand patient-disease variations. Therefore, NAFLD is considered a complex and mutifactorial disease phenotype resulting from environmental exposures acting on a susceptible polygenic background. This paper reviewed the current status of proteomic and genomic studies that have contributed to the understanding of NAFLD pathogenesis. For proteomics section, this review highlighted functional proteins that involved in: (1) transportation; (2) metabolic pathway; (3) acute phase reaction; (4) anti-inflammatory; (5) extracellular matrix; and (6) immune system. In the genomic studies, this review will discuss genes which involved in: (1) lipolysis; (2) adipokines; and (3) cytokines production.
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The effects of strength and power training on single-step balance recovery in older adults: a preliminary study.
Clin Interv Aging
PUBLISHED: 01-01-2014
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Improving muscle strength and power may mitigate the effects of sarcopenia, but it is unknown if this improves an older adult's ability to recover from a large postural perturbation. Forward tripping is prevalent in older adults and lateral falls are important due to risk of hip fracture. We used a forward and a lateral single-step balance recovery task to examine the effects of strength training (ST) or power (PT) training on single-step balance recovery in older adults. Twenty older adults (70.8±4.4 years, eleven male) were randomly assigned to either a 6-week (three times/week) lower extremity ST or PT intervention. Maximum forward (FLean(max)) and lateral (LLean(max)) lean angle and strength and power in knee extension and leg press were assessed at baseline and follow-up. Fifteen participants completed the study (ST =7, PT =8). Least squares means (95% CI) for ?FLean(max) (ST: +4.1° [0.7, 7.5]; PT: +0.6° [-2.5, 3.8]) and ?LLean(max) (ST: +2.2° [0.4, 4.1]; PT: +2.6° [0.9, 4.4]) indicated no differences between groups following training. In exploratory post hoc analyses collapsed by group, ?FLean(max) was +2.4° (0.1, 4.7) and ?LLean(max) was +2.4° (1.2, 3.6). These improvements on the balance recovery tasks ranged from ~15%-30%. The results of this preliminary study suggest that resistance training may improve balance recovery performance, and that, in this small sample, PT did not lead to larger improvements in single-step balance recovery compared to ST.
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In Vitro Characterization of MK-1439: A Novel HIV-1 Non-Nucleoside Reverse transcriptase Inhibitor.
Antimicrob. Agents Chemother.
PUBLISHED: 12-30-2013
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Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are a mainstay of therapy for treating human immunodeficiency type 1 virus (HIV-1)-infected patients. MK-1439 is a novel NNRTI with IC50 of 12, 9.7, and 9.7 nM against wild-type (WT), K103N, and Y181C reverse transcriptase (RT) in a biochemical assay, respectively. Selectivity and cytotoxicity studies confirmed that MK-1439 is a highly specific NNRTI with minimum off-target activities. In the presence of 50% normal human serum (NHS), MK-1439 showed excellent potency in suppressing the replication of WT virus with EC95 of 20 nM as well as K103N, Y181C, and K103N/Y181C mutant viruses with EC95 of 43, 27, and 55 nM, respectively. MK-1439 exhibited similar antiviral activities against 10 different HIV-1 subtype viruses (a total of 93 viruses). In addition, the susceptibility of a broader array of clinicalNNRTI-associated mutant viruses (a total of 96 viruses) to MK-1439 and other benchmark NNRTIs was investigated. The results showed that the mutant profile of MK-1439 was superior overall to that of efavirenz (EFV) and comparable to that of etravirine (ETR) and rilpivirine (RPV). Furthermore, E138K, Y181C, and K101E mutant viruses that are associated with ETR and RPV were susceptible to MK-1439 with fold-change (FC) < 3. A two-drug in vitro combination study indicated that MK-1439 acts non-antagonistically in the antiviral activity with each of 18 FDA licensed drugs for HIV infection. Taken together, these in vitro data suggest that MK-1439 possesses the desired properties for further development as a new antiviral agent.
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Work environment perceptions following relocation to open-plan offices: A twelve-month longitudinal study.
Work
PUBLISHED: 11-29-2013
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A workplaces design can have various positive or negative effects on the employees and since the 1970s the advantages and disadvantages of open-plan offices have been discussed.
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HIV-2 antiviral potency and selection of drug resistance mutations by the integrase strand transfer inhibitor elvitegravir and NRTIs emtricitabine and tenofovir in vitro.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 10-30-2013
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HIV-2 is susceptible to only a subset of approved antiretroviral drugs. A single tablet regimen containing the integrase strand transfer inhibitor elvitegravir (EVG) boosted by cobicistat plus the nucleoside reverse transcriptase (RT) inhibitors emtricitabine (FTC) and tenofovir disoproxil fumarate (EVG/COBI/FTC/TDF) has potent activity against HIV-1 and may have utility against HIV-2.
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Effects of Randomization to Intensive Glucose Control on Adverse Events, Cardiovascular Disease and Mortality in Older Versus Younger Adults in the ACCORD Trial.
Diabetes Care
PUBLISHED: 10-29-2013
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ObjectiveTo explore the effect of randomized treatment comparing intensive to standard glucose lowering strategies on major cardiovascular outcomes, death, and severe adverse events in older versus younger participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial.Research Design and MethodsParticipants with type 2 diabetes (n=10,251) with mean age 62yrs, median duration of diabetes 10yrs, and median A1C 8.1% (65 mmol/mol) were randomized to treatment strategies targeting either A1C<6.0% (42 mmol/mol) or 7.0-7.9% (53-63 mmol/mol) and followed for a mean of 3.7yrs. Outcomes were analyzed within subgroups defined by baseline age (<65yrs versus ?65 yrs).ResultsOlder and younger ACCORD participants achieved similar intensive arm A1C levels and between-arm A1C differences. Within the older subgroup, similar hazards of the cardiovascular primary outcome and total mortality were observed in the two arms. While there was no intervention effect on cardiovascular mortality in the older subgroup, there was an increased risk in the intensive arm for the younger subgroup (older HR=0.97; younger HR=1.71; p=0.03). Regardless of intervention arm, the older subgroup experienced higher annualized rates of severe hypoglycemia (4.45% intensive and 1.36% standard) than the younger subgroup (2.45% intensive and 0.80% standard).ConclusionsIntensive glucose lowering increased the risk of CVD and total mortality in younger participants whereas it had a neutral effect in older participants. The intensive to standard relative risk of severe hypoglycemia was similar in both age subgroups with higher absolute rates in older participants within both treatment arms.
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Stereocontrolled synthesis of 1,3-diols from enones: cooperative Lewis base-mediated intramolecular carbonyl hydrosilylations.
J. Org. Chem.
PUBLISHED: 09-06-2013
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A streamlined synthesis of ?-hydroxy ketone substrates has been developed to further investigate a recently discovered cooperative Lewis base-mediated intramolecular carbonyl hydrosilylation reaction. The synthesis features an enone ?-borylation/oxidation sequence that has proven to be quite general and high-yielding. This has allowed for additional investigations into the diastereoselectivity of the hydrosilylation reaction through the preparation of important polyketide fragments.
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Measurement of downstream kinase activity modulation as indicator of epidermal growth factor receptor inhibitor efficacy.
Anal. Biochem.
PUBLISHED: 09-04-2013
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The acoustic micro magnetic particle (AMMP) technology has been used to quantify single analytes out of multiple sample types. In this study the technology is used to reveal molecular interactions of components of kinase pathways. Specifically, the downstream kinase activity of the EGFR receptor in the presence or absence of EGFR inhibitors is investigated. These experiments substantiate that EGFR stimulation predominantly activates the MEK/ERK pathway. The EGFR inhibitors tested had varying effectiveness at preventing phosphorylation at the EGFR or downstream kinase activity. These experiments reveal the use of the AMMP technology for observing multiple signaling pathways in a single experiment.
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Development and characterization of a replicon-based phenotypic assay for assessing HCV NS4B from clinical isolates.
Antiviral Res.
PUBLISHED: 08-23-2013
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The hepatitis C virus (HCV) NS4B inhibitors have shown potent inhibition of HCV replication in vitro. To assess the effect of viral diversity on the susceptibility to NS4B inhibitors, genotype (GT)-specific GT1a and GT1b replicon shuttle vectors were designed and created for cloning HCV NS4B genes from clinical isolates. For the GT1b NS4B shuttle vector, the S2204I adaptive mutation was introduced in NS5A to improve replication due to the replacement of the K1846T adaptive mutation in NS4B with NS4B from the clinical isolates. In addition to the adaptive mutations, a newly identified Huh-7 cell line, Huh-7-1C, which is highly permissive for both GT1a and GT1b replication, was used to further enhance the replication levels. HCV NS4B gene from clinical isolates was amplified and inserted into the corresponding GT1a and GT1b modified lab strain chimeric replicons. GT1a and GT1b chimeric replicons expressing diverse NS4B genes from corresponding subtypes of clinical isolates replicated at highly efficient levels for phenotypic analysis. Due to natural variation in their amino acid residues in NS4B, these isolates displayed varying drug susceptibilities to an NS4B inhibitor. In mixed populations with wild-type, the sensitivity of resistance detection of NS4B resistant mutants H94R and V105M was between 20% and 80%. The chimeric shuttle vectors can be used to characterize the activity of antiviral drugs targeting NS4B from diverse natural clinical isolates and aid in the development of novel compounds against HCV NS4B.
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Association of depression with accelerated cognitive decline among patients with type 2 diabetes in the ACCORD-MIND trial.
JAMA Psychiatry
PUBLISHED: 08-16-2013
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Depression has been identified as a risk factor for dementia among patients with type 2 diabetes mellitus but the cognitive domains and patient groups most affected have not been identified.
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Validation of endoscopic activity scores in patients with Crohns disease based on a post hoc analysis of data from SONIC.
Gastroenterology
PUBLISHED: 08-05-2013
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Mucosal healing might alter midterm and long-term outcomes of patients with Crohns disease (CD) and has become an important end point in clinical trials. However, the minimal degree of mucosal improvement (endoscopic response) required to alter midterm outcomes is not known. We aimed to determine the best definition of endoscopic response by evaluating data on the Simple Endoscopic Score for Crohns Disease (SES-CD) and the Crohns Disease Endoscopic Index of Severity (CDEIS) from the Study of Biologic and Immunomodulator Naive Patients in Crohns Disease (SONIC trial).
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High-density lipoproteins: a consensus statement from the National Lipid Association.
J Clin Lipidol
PUBLISHED: 07-29-2013
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For >4 decades it has been recognized that elevated serum levels of high-density lipoprotein cholesterol (HDL-C) are associated with reduced risk of cardiovascular disease (CVD) and its sequelae. Many prospective observational studies performed around the world have confirmed an inverse relationship between HDL-C and cardiovascular risk in people irrespective of sex, race, or ethnicity. Consequently, it was assumed that, by extension, raising HDL-C through lifestyle modification and pharmacologic intervention would reduce risk of CVD. Animal studies are consistent with this assumption. Lipid treatment guidelines around the world promoted the recognition of HDL-C as a therapeutic target, especially in high-risk patients. Some post hoc analyses from randomized controlled trials also suggest that raising HDL-C beneficially affects the risk of CVD. However, a number of recent randomized studies putatively designed to test the "HDL hypothesis" have failed to show benefit. The results of these trials have caused many clinicians to question whether HDL-C is a legitimate therapeutic target. In response to the many questions and uncertainties raised by the results of these trials, the National Lipid Association convened an expert panel to evaluate the current status of HDL-C as a therapeutic target; to review the current state of knowledge of HDL particle structure, composition, and function; and to identify the salient questions yet to be answered about the role of HDL in either preventing or contributing to atherosclerotic disease. The expert panels conclusions and clinical recommendations are summarized herein. The panel concludes that, although low HDL-C identifies patients at elevated risk, and much investigation suggests that HDL may play a variety of antiatherogenic roles, HDL-C is not a therapeutic target at the present time. Risk stratified atherogenic lipoprotein burden (low-density lipoprotein cholesterol and non-HDL-C) should remain the primary and secondary targets of therapy in patients at risk, as described by established guidelines. The National Lipid Association emphasizes that rigorous research into the biology and clinical significance of low HDL-C should continue. The development of novel drugs designed to modulate the serum levels and functionality of HDL particles should also continue. On the basis of an enormous amount of basic scientific and clinical investigation, a considerable number of reasons support the need to continue to investigate the therapeutic effect of modulating HDL structure and function.
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Characterization of Hepatitis C virus resistance from a multiple-dose clinical trial of the novel NS5A inhibitor GS-5885.
Antimicrob. Agents Chemother.
PUBLISHED: 07-22-2013
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GS-5885 is a novel hepatitis C virus (HCV) NS5A inhibitor. In a 3-day monotherapy study in treatment-naive genotype 1a (GT1a) and GT1b HCV-infected subjects, median viral load reductions ranged from 2.3 to 3.3 log10 HCV RNA IU/ml across dosing cohorts (1, 3, 10, 30, or 90 mg once daily). Here, we report viral sequencing and phenotypic analysis of clinical isolates from this study. Detection of baseline NS5A amino acid substitutions at positions 28, 30, 31, or 93 in GT1a was associated with a reduced treatment response. In the GT1b cohort, Y93H was detected in 100% of subjects at day 4 or 14. In the Gt1a cohort, population sequencing detected NS5A resistance-associated mutations at day 4 or 14 for 3/10 subjects at the 1-mg dose and for all subjects dosed at ?3 mg. A subset of mutants that confer a low level of reduced susceptibility to GS-5885 was not detected by population sequencing at the 30- and 90-mg doses. Subject-derived M28T, Q30R, L31M, and Y93C mutations all conferred >30-fold reductions in GS-5885 and daclatasvir susceptibilities in vitro. Site-directed NS5A mutants also showed reduced susceptibility to GS-5885. However, all NS5A mutants tested remained fully susceptible to other classes of direct-acting antivirals (DAAs), interferon alpha, and ribavirin. Importantly, the nonoverlapping resistance profile and high potency of GS-5885 support its further development with other direct-acting antivirals for the treatment of chronic HCV. (This study has been registered at ClinicalTrials.gov under registration number NCT01193478.).
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The use of social-networking sites in medical education.
Med Teach
PUBLISHED: 07-10-2013
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A social-network site is a dedicated website or application which enables users to communicate with each other and share information, comments, messages, videos and images. Aims: This review aimed to ascertain if "social-networking sites have been used successfully in medical education to deliver educational material", and whether "healthcare professionals, and students, are engaging with social-networking sites for educational purposes".
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Dead-end complexes contribute to the synergistic inhibition of HIV-1 RT by the combination of rilpivirine, emtricitabine, and tenofovir.
Antiviral Res.
PUBLISHED: 07-01-2013
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The single tablet regimen of the nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) tenofovir disoproxil fumarate (TDF), emtricitabine (FTC), and the non-nucleoside reverse transcriptase inhibitor (NNRTI) rilpivirine (RPV) is approved for the treatment of HIV-1 infection in treatment-naïve adults. Previous studies have shown that two-drug combinations of these drugs show additive to synergistic HIV-1 antiviral activity in cell culture. In this study, two-drug combinations of tenofovir (TFV)+FTC, RPV+TFV, and RPV+FTC inhibited HIV-1 replication in cell culture with strong synergy and no evidence of antagonism. The triple drug combination of RPV+FTC+TFV displayed moderate synergy comparable to efavirenz (EFV)+FTC+TFV. The formation of dead-end complexes (DEC) of HIV-1 reverse transcriptase (RT), NRTI chain-terminated primer/template, and the next complementary nucleotide or NNRTIs was studied using gel mobility shift assays. DEC formation was seen with TFV-terminated DNA primer/template, HIV-1 RT, and FTC-triphosphate (TP) in addition to the natural nucleotide dCTP, thus stabilizing chain-termination. The NNRTI RPV also formed DEC-like complexes with TFV- and FTC-monophosphate (MP)-terminated DNA primer/templates and HIV-1 RT, and stabilized chain-termination by both NRTIs. Overall, the combinations of RPV, FTC, and TFV inhibit HIV-1 replication with moderate to strong synergy. This may be partially explained by enhanced DEC formation of NRTI chain-terminated DNA primer/template and HIV-1 RT in the presence of the other drugs in the combination, leading to more stable chain-termination and replication inhibition by NRTIs.
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Reductions in anxiety and depression symptoms in youth receiving substance use treatment.
Am J Addict
PUBLISHED: 06-26-2013
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Research shows that interventions for substance use disorders may be helpful in reducing internalizing disorders in adolescents. This paper examines the prevalence and reductions of anxiety and depression symptoms among youth receiving substance use treatment.
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Early progression of diabetic nephropathy correlates with methylglyoxal-derived advanced glycation end products.
Diabetes Care
PUBLISHED: 06-18-2013
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Increased advanced glycation end products (AGEs) and oxidation products (OPs) are proposed to lead to progression of diabetic nephropathy (DN). We investigated the relationship between AGEs, OPs, and progression of DN in 103 subjects with type 1 diabetes participating in the Natural History of Diabetic Nephropathy Study.
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Analysis of Factors Contributing to Severity of Breast Cancer-Related Lymphedema.
Ann Plast Surg
PUBLISHED: 06-14-2013
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BACKGROUND: Upper extremity lymphedema is a well-described complication of breast cancer treatment. Risk factors for lymphedema development include axillary lymph node dissection (ALND), obesity, increasing age, radiation, and postoperative complications. In this study, we seek to evaluate a cohort of patients who have either self-referred or been referred to the Department of Physical Therapy for lymphedema treatment. Our goal is to evaluate specific risk factors associated with the severity of lymphedema in this patient population. METHODS: All patients who presented to the Wexner Medical Center at the Ohio State University between January 1, 2009, and December 31, 2010, with a chief complaint of upper extremity lymphedema after breast cancer treatment were reviewed retrospectively. Upper extremity lymphedema index (UELI) was used as a severity indicator and patient factors including demographics and breast cancer treatments were evaluated. Univariate and multivariate statistical analyses were performed. RESULTS: Fifty (4.5%) patients presented for upper extremity lymphedema treatment after breast cancer treatment (total of 1106 patients treated surgically for breast cancer). Greater UELIs were found in patients 50 years and older, those with ALND, radiation, chemotherapy, pathologic stage greater than 3, and an International Society of Lymphology lymphedema stage II (P < 0.05). The multivariate model showed age older than 50 years and pathologic stage greater than 3 were significant predictors of higher UELI (P < 0.05). CONCLUSIONS: In this study, we report that in patients who present for lymphedema treatment, increased UELI is significantly related to ALND, radiation therapy, chemotherapy, age, and pathologic stage. An improved understanding of the patient population referred for lymphedema treatment will allow for the identification of patients who may be candidates for therapeutic intervention.
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Association between circulating vitamin K1 and coronary calcium progression in community-dwelling adults: the Multi-Ethnic Study of Atherosclerosis.
Am. J. Clin. Nutr.
PUBLISHED: 05-29-2013
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Animal studies have shown that vitamin K treatment reduced vascular calcification, but human data are limited.
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HBV clinical isolates expressing adefovir resistance mutations show similar tenofovir susceptibilities across genotypes B, C and D.
Liver Int.
PUBLISHED: 04-12-2013
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Hepatitis B virus (HBV) genotypes can influence clinical outcomes as well as response to antiviral therapy. This study evaluated the tenofovir (TFV) susceptibility of HBV genotype B, C and D clinical isolates with adefovir resistance-associated mutations (ADV-R).
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Barriers to a cure for HIV: new ways to target and eradicate HIV-1 reservoirs.
Lancet
PUBLISHED: 03-29-2013
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Antiretroviral therapy for HIV infection needs lifelong access and strict adherence to regimens that are both expensive and associated with toxic effects. A curative intervention will be needed to fully stop the epidemic. The failure to eradicate HIV infection during long-term antiretroviral therapy shows the intrinsic stability of the viral genome in latently infected CD4T cells and other cells, and possibly a sustained low-level viral replication. Heterogeneity in latently infected cell populations and homoeostatic proliferation of infected cells might affect the dynamics of virus production and persistence. Despite potent antiretroviral therapy, chronic immune activation, inflammation, and immune dysfunction persist, and are likely to have important effects on the size and distribution of the viral reservoir. The inability of the immune system to recognise cells harbouring latent virus and to eliminate cells actively producing virus is the biggest challenge to finding a cure. We look at new approaches to unravelling the complex virus-host interactions that lead to persistent infection and latency, and discuss the rationale for combination of novel treatment strategies with available antiretroviral treatment options to cure HIV.
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Impact of primary elvitegravir resistance-associated mutations in HIV-1 integrase on drug susceptibility and viral replication fitness.
Antimicrob. Agents Chemother.
PUBLISHED: 03-25-2013
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Elvitegravir (EVG) is an effective HIV-1 integrase (IN) strand transfer inhibitor (INSTI) in advanced clinical development. Primary INSTI resistance-associated mutations (RAMs) at six IN positions have been identified in HIV-1-infected patients failing EVG-containing regimens in clinical studies: T66I/A/K, E92Q/G, T97A, S147G, Q148R/H/K, and N155H. In this study, the effect of these primary IN mutations, alone and in combination, on susceptibility to the INSTIs EVG, raltegravir (RAL), and dolutegravir (DTG); IN enzyme activities; and viral replication fitness was characterized. Recombinant viruses containing the six most common mutations exhibited a range of reduced EVG susceptibility: 92-fold for Q148R, 30-fold for N155H, 26-fold for E92Q, 10-fold for T66I, 4-fold for S147G, and 2-fold for T97A. Less commonly observed primary IN mutations also showed a range of reduced EVG susceptibilities: 40- to 94-fold for T66K and Q148K and 5- to 10-fold for T66A, E92G, and Q148H. Some primary IN mutations exhibited broad cross-resistance between EVG and RAL (T66K, E92Q, Q148R/H/K, and N155H), while others retained susceptibility to RAL (T66I/A, E92G, T97A, and S147G). Dual combinations of primary IN mutations further reduced INSTI susceptibility, replication capacity, and viral fitness relative to either mutation alone. Susceptibility to DTG was retained by single primary IN mutations but reduced by dual mutation combinations with Q148R. Primary EVG RAMs also diminished IN enzymatic activities, concordant with their structural proximity to the active site. Greater reductions in viral fitness of dual mutation combinations may explain why some primary INSTI RAMs do not readily coexist on the same HIV-1 genome but rather establish independent pathways of resistance to EVG.
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Interns success with clinical procedures in infants after simulation training.
Pediatrics
PUBLISHED: 02-25-2013
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Simulation-based medical education (SBME) is used to teach residents. However, few studies have evaluated its clinical impact. The goal of this study was to evaluate the impact of an SBME session on pediatric interns clinical procedural success.
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Durable efficacy and safety of raltegravir versus efavirenz when combined with tenofovir/emtricitabine in treatment-naive HIV-1-infected patients: final 5-year results from STARTMRK.
J. Acquir. Immune Defic. Syndr.
PUBLISHED: 02-16-2013
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STARTMRK, a phase III noninferiority trial of raltegravir-based versus efavirenz-based therapy in treatment-naive patients, remained blinded until its conclusion at 5 years. We now report the final study results.
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Detection of diabetic nephropathy from advanced glycation endproducts (AGEs) differs in plasma and urine, and is dependent on the method of preparation.
Amino Acids
PUBLISHED: 01-28-2013
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Increased advanced glycation endproducts (AGEs) and oxidation products (OPs) have been proposed as pathogenic for diabetic nephropathy (DN). We investigated the relationship between AGEs and OPs measured in different plasma and urine preparations, and progression of DN in 103 young, normoalbuminuric, normotensive participants with type 1 diabetes in the Natural History of Diabetic Nephropathy Study. The primary endpoint was electron microscopy-measured change in glomerular basement membrane (GBM) width from baseline to 5 years; change in mesangial fractional volume was a secondary endpoint. Fast progressors (FP) were defined as the upper quartile (n = 24) of rate of GBM thickening; slow progressors (SP) were the remainder (n = 79). Four AGEs [3-deoxyglucosone and methylglyoxal hydroimidazolones (DG3H1, MGH1) and carboxymethyl and ethyl lysine (CML, CEL)], and two oxidation products methionine sulfoxide and aminoadipic acid were measured by liquid chromatography, triple quadrupole mass spectrometry. Measurements were done on 10 K plasma filtrates and plasma proteolytic digests (PPD) at year 5, and at four time points over 5 years for urinary 10 K filtrates. Urinary filtrate CEL levels were significantly higher in FP, but not after adjustment for HbA1c, sex, and duration of diabetes. MGHI, CEL, and CML plasma filtrate levels were significantly higher in FP relative to SP (p < 0.05). In PPD, only MGHI showed borderline significantly higher levels in FP relative to SP (p = 0.067), while no other product showed correlation. AGE and OP measurements were not correlated with mesangial expansion. In plasma filtrates, HbA1c at year 5 accounted for 4.7 % of the variation in GBM width. The proportion of variation in GBM width was increased to 11.6 % when MGHI, CEL, and CML were added to the model (6.9 % increase).
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Expression of fungal cutinase and swollenin in tobacco chloroplasts reveals novel enzyme functions and/or substrates.
PLoS ONE
PUBLISHED: 01-18-2013
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In order to produce low-cost biomass hydrolyzing enzymes, transplastomic lines were generated that expressed cutinase or swollenin within chloroplasts. While swollenin expressing plants were homoplasmic, cutinase transplastomic lines remained heteroplasmic. Both transplastomic lines showed interesting modifications in their phenotype, chloroplast structure, and functions. Ultrastructural analysis of chloroplasts from cutinase- and swollenin-expressing plants did not show typical lens shape and granal stacks. But, their thylakoid membranes showed unique scroll like structures and chloroplast envelope displayed protrusions, stretching into the cytoplasm. Unusual honeycomb structures typically observed in etioplasts were observed in mature chloroplasts expressing swollenin. Treatment of cotton fiber with chloroplast-derived swollenin showed enlarged segments and the intertwined inner fibers were irreversibly unwound and fully opened up due to expansin activity of swollenin, causing disruption of hydrogen bonds in cellulose fibers. Cutinase transplastomic plants showed esterase and lipase activity, while swollenin transplastomic lines lacked such enzyme activities. Higher plants contain two major galactolipids, monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), in their chloroplast thylakoid membranes that play distinct roles in their structural organization. Surprisingly, purified cutinase effectively hydrolyzed DGDG to MGDG, showing alpha galactosidase activity. Such hydrolysis resulted in unstacking of granal thylakoids in chloroplasts and other structural changes. These results demonstrate DGDG as novel substrate and function for cutinase. Both MGDG and DGDG were reduced up to 47.7% and 39.7% in cutinase and 68.5% and 67.5% in swollenin expressing plants. Novel properties and functions of both enzymes reported here for the first time should lead to better understanding and enhanced biomass hydrolysis.
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Probiotic/prebiotic supplementation of antiretrovirals improves gastrointestinal immunity in SIV-infected macaques.
J. Clin. Invest.
PUBLISHED: 01-16-2013
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HIV infection results in gastrointestinal (GI) tract damage, microbial translocation, and immune activation, which are not completely ameliorated with suppression of viremia by antiretroviral (ARV) therapy. Furthermore, increased morbidity and mortality of ARV-treated HIV-infected individuals is associated with these dysfunctions. Thus, to enhance GI tract physiology, we treated SIV-infected pigtail macaques with ARVs, probiotics, and prebiotics or with ARVs alone. This synbiotic treatment resulted in increased frequency and functionality of GI tract APCs, enhanced reconstitution and functionality of CD4+ T cells, and reduced fibrosis of lymphoid follicles in the colon. Thus, ARV synbiotic supplementation in HIV-infected individuals may improve GI tract immunity and thereby mitigate inflammatory sequelae, ultimately improving prognosis.
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External hemipelvectomy pelvic ring stabilization: the unique application of chimeric lower extremity pedicled fillet flaps.
J Reconstr Microsurg
PUBLISHED: 01-15-2013
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Reconstruction of large external hemipelvectomy oncologic defects of the proximal limb and trunk remains a formidable surgical challenge. Large pelvic defects can result in exposed bones, neurovascular structures, and surgical hardware due to a paucity of soft tissue coverage. When the size of a hemipelvectomy defect precludes coverage by local posterior- or anterior-based hemipelvectomy flaps, the use of other local flaps must be considered before resorting to free tissue transfer. The rectus abdominis myocutaneous pedicled flap is the most commonly used locoregional flap for soft tissue coverage of large hemipelvectomy soft tissue defects. The concept of utilizing parts from otherwise nonsalvageable limb components in reconstruction is well described in the literature and referred to as the "spare parts" concept. Utilization of these distal "spare parts" has the advantage of obtaining sufficient soft tissue coverage while concurrently obviating additional donor-site morbidity. These spare parts can be utilized as either pedicled or free fillet flaps. This paper describes the unique use of in-continuity chimeric pedicled fillet flaps of the lower extremity to reconstruct and stabilize the pelvic ring, to obliterate dead space, and to provide overlying soft tissue coverage.
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The effects of ezetimibe/simvastatin versus simvastatin monotherapy on platelet and inflammatory biomarkers in patients with metabolic syndrome.
Cardiology
PUBLISHED: 01-11-2013
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In a randomized, double-blind, crossover study of 15 aspirin-naive patients (mean age 48.8 ± 10.2 years) with the metabolic syndrome, statin monotherapy (simvastatin 40 mg daily) was compared to combination therapy (simvastatin 40 mg and ezetimibe 10 mg daily) on biomarkers of inflammation and platelet activity. The addition of ezetimibe to simvastatin over a 4-week period was associated with reduced expression of CD141 (thrombomodulin; p = 0.02), platelet endothelial cell adhesion molecule (p < 0.0001) and CD51/61 (vitronectin receptor; p = 0.048) compared to statin monotherapy. Ezetimibe added to simvastatin improves several indices of platelet reactivity beyond statin monotherapy. However, the clinical relevance of these findings await results of the IMPROVE-IT trial (Improved Reduction of Outcomes: Vytorin Efficacy International Trial).
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Promoting physical activity for elders with compromised function: the lifestyle Interventions and Independence for elders (LIFE) study physical activity intervention.
Clin Interv Aging
PUBLISHED: 01-01-2013
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The Lifestyle Interventions and Independence for Elders (LIFE) Study is a Phase III randomized controlled clinical trial (Clinicaltrials.gov identifier: NCT01072500) that will provide definitive evidence regarding the effect of physical activity (PA) on major mobility disability in older adults (70-89 years old) who have compromised physical function. This paper describes the methods employed in the delivery of the LIFE Study PA intervention, providing insight into how we promoted adherence and monitored the fidelity of treatment. Data are presented on participants motives and self-perceptions at the onset of the trial along with accelerometry data on patterns of PA during exercise training. Prior to the onset of training, 31.4% of participants noted slight conflict with being able to meet the demands of the program and 6.4% indicated that the degree of conflict would be moderate. Accelerometry data collected during PA training revealed that the average intensity - 1,555 counts/minute for men and 1,237 counts/minute for women - was well below the cutoff point used to classify exercise as being of moderate intensity or higher for adults. Also, a sizable subgroup required one or more rest stops. These data illustrate that it is not feasible to have a single exercise prescription for older adults with compromised function. Moreover, the concept of what constitutes "moderate" exercise or an appropriate volume of work is dictated by the physical capacities of each individual and the level of comfort/stability in actually executing a specific prescription.
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Resistance mutations outside the integrase coding region have an effect on human immunodeficiency virus replicative fitness but do not affect its susceptibility to integrase strand transfer inhibitors.
PLoS ONE
PUBLISHED: 01-01-2013
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Most studies describing phenotypic resistance to integrase strand transfer inhibitors have analyzed viruses carrying only patient-derived HIV-1 integrase genes (INT-recombinant viruses). However, to date, many of the patients on INSTI-based treatment regimes, such as raltegravir (RAL), elvitegravir (EVG), and dolutegravir (DTG) are infected with multidrug-resistant HIV-1 strains. Here we analyzed the effect of drug resistance mutations in Gag (p2/NCp7/p1/p6), protease (PR), reverse transcriptase (RT), and integrase (IN) coding regions on susceptibility to INSTIs and viral replicative fitness using a novel HIV-1 phenotyping assay. Initial characterization based on site-directed mutant INSTI-resistant viruses confirmed the effect of a series of INSTI mutations on reduced susceptibility to EVG and RAL and viral replicative fitness (0.6% to 99% relative to the HIV-1NL4-3 control). Two sets of recombinant viruses containing a 3,428-bp gag-p2/NCp7/p1/p6/pol-PR/RT/IN (p2-INT) or a 1,088 bp integrase (INT) patient-derived fragment were constructed from plasma samples obtained from 27 virologic failure patients participating in a 48-week dose-ranging study of elvitegravir, GS-US-183-0105. A strong correlation was observed when susceptibility to EVG and RAL was assayed using p2-INT- vs. INT-recombinant viruses (Pearson coefficient correlation 0.869 and 0.918, P<0.0001 for EVG and RAL, respectively), demonstrating that mutations in the protease and RT have limited effect on susceptibility to these INSTIs. On the other hand, the replicative fitness of viruses harboring drug resistance mutations in PR, RT, and IN was generally impaired compared to viruses carrying only INSTI-resistance mutations. Thus, in the absence of drug pressure, drug resistance mutations in the PR and RT contribute to decrease the replicative fitness of the virus already impaired by mutations in the integrase. The use of recombinant viruses containing most or all HIV-1 regions targeted by antiretroviral drugs might be essential to understand the collective effect of epistatic interactions in multidrug-resistant viruses.
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The impact of frequent and unrecognized hypoglycemia on mortality in the ACCORD study.
Diabetes Care
PUBLISHED: 12-16-2011
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The aim of this study was to examine the relationship between frequent and unrecognized hypoglycemia and mortality in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study cohort.
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Use of the Case Western Reserve/Veterans Administration neuroprosthesis for exercise, standing and transfers by a paraplegic subject.
Disabil Rehabil Assist Technol
PUBLISHED: 11-04-2011
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Functional electric stimulation (FES) is a technology that may allow patients with spinal cord injury (SCI) to transfer stand and walk. This paper reports upon the use of the Case Western Reserve Neuroprosthesis by a T6 ASIA B paraplegic subject. The subject was able to stand for two minutes and 50 seconds. He could walk 35 feet with a swing to gait. Measurement of energy consumption showed that metabolic demand was only 2.1 metabolic equivalent units. The factors that limited the use of the device that need to be improved to make the technology practical for household or community ambulation are speed (5.8 m/min) of ambulation and fatigue of the stimulated muscles.
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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.

Video X seems to be unrelated to Abstract Y...

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.