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Objective: To determine whether the introduction of a multidisciplinary intrapartum perineal-care training program reduced the rate of obstetric anal sphincter injuries in patients undergoing vaginal deliveries., Methods: A prospective observational cohort study enrolled women undergoing vaginal deliveries at a district general hospital maternity unit in the United Kingdom between April 1, 2012 and March 31, 2014. All women experiencing obstetric anal sphincter injuries during the study period were identified and the rate of obstetric anal sphincter injuries before (2012-2013) a multidisciplinary training program was implemented was compared with the rate after (2013-2014) implementation using logistic regression analysis., Results: The study enrolled 4920 patients. Following the implementation of the training program, the rate of obstetric anal sphincter injuries decreased from 4.8% to 3.1% of vaginal deliveries (odds ratio 0.66; 95% confidence interval 0.493-0.899; P = 0.008)., Conclusions: The integration of intrapartum perineal-care training into mandatory annual staff training was associated with a statistically and clinically significant reduction in the rate of obstetric anal sphincter injuries., (Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.)

The use of human pluripotent cell progeny for cardiac disease modeling, drug testing and therapeutics requires the ability to efficiently induce pluripotent cells into the cardiomyogenic lineage. Although direct activation of the Activin-A and/or Bmp pathways with growth factors yields context-dependent success, recent studies have shown that induction of Wnt signaling using low molecular weight molecules such as CHIR, which in turn induces the Activin-A and Bmp pathways, is widely effective. To further enhance the reproducibility of CHIR-induced cardiomyogenesis, and to ultimately promote myocyte maturation, we are using exogenous growth factors to optimize cardiomyogenic signaling downstream of CHIR induction. As indicated by RNA-seq, induction with CHIR during Day 1 (Days 0-1) was followed by immediate expression of Nodal ligands and receptors, followed later by Bmp ligands and receptors. Co-induction with CHIR and high levels of the Nodal mimetic Activin-A (50-100 ng/ml) during Day 0-1 efficiently induced definitive endoderm, whereas CHIR supplemented with Activin-A at low levels (10 ng/ml) consistently improved cardiomyogenic efficiency, even when CHIR alone was ineffective. Moreover, co-induction using CHIR and low levels of Activin-A apparently increased the rate of cardiomyogenesis, as indicated by the initial appearance of rhythmically beating cells by Day 6 instead of Day 8. By contrast, co-induction with CHIR plus low levels (3-10 ng/ml) of Bmp4 during Day 0-1 consistently and strongly inhibited cardiomyogenesis. These findings, which demonstrate that cardiomyogenic efficacy is improved by optimizing levels of CHIR-induced growth factors when applied in accord with their sequence of endogenous expression, are consistent with the idea that Nodal (Activin-A) levels toggle the entry of cells into the endodermal or mesodermal lineages, while Bmp levels regulate subsequent allocation into mesodermal cell types.

Background: The prevalence of HIV-associated neurocognitive disorders is increasing as HIV-infected individuals are living longer. The clinical manifestations of the syndrome also continue to evolve under the influence of antiretroviral drugs and comorbidities such as drugs of abuse. However, there are no surrogate markers for the disease, either to identify it de novo or to track its progression, and there is no proven treatment with the exception of antiretroviral drugs., Methods: Levels of nitric oxide, nitrate, and 3-nitrotyrosine (3-NT)-modified proteins were measured in the CSF of 46 patients with HIV infection stratified according to their neurocognitive status and history of IV drug use (IVD). The 3-NT-modified proteins were isolated and identified by tandem mass spectrometry, and the functional consequence of 3-NT modification of L-prostaglandin D synthase (L-PGDS), the most abundant protein, was determined., Results: 3-NT-modified proteins were significantly elevated in patients with HIV infection who had progressive neurocognitive decline over the next 6 months and in patients with a history of IVD. Thirteen different proteins with 3-NT modification were identified in the CSF of these patients. L-PGDS was the most abundant. 3-NT modification of this protein resulted in loss of its enzymatic activity., Conclusions: There is increased nitrosative stress in CSF of HIV-infected patients with active dementia and in patients with a history of IV drug use, measurement of which may serve as a surrogate marker for these patients. Nitrosative stress may also have important functional consequences and may impact the pathogenesis of HIV-associated neurocognitive disorders.

A dual reflectron tandem time-of-flight (TOF/TOF) mass spectrometer reported in 1993 gave rise to the invention and development of the curved-field reflectron (CFR) for focusing product ions. The CFR is used in this case as the second mass analyzer in a tandem instrument (based on the Kratos AXIMA CFR) in which the first mass analyzer is a linear TOF that focuses ions by pulsed extraction. Because ions can be focused over a broad range of kinetic energies, deceleration of precursor ions and/or reacceleration of product ions is not required. Thus, product ions produced by post-source processes (laser induced dissociation or LID, metastable decomposition and opportunistic collisions) are recorded in the product ion mass spectra at the same times as their isomass ions produced by collision induced dissociation (CID). In general both LID and CID product ion mass spectra are very similar, producing primarily b-series and y-series ions, though there is some preference for fragmentation at weaker bonds such as those at proline or aspartic acid residues. The tandem mass spectrometer has been used to determine the acetylation sites for a histone acetyl transferase (HAT) protein. A novel and improved method for derivatizing tryptic fragments by N-terminal sulfonation produces almost exclusively y-series ions, and has been used to determine protein ubiquitination. The tandem mass spectrometer has also been used to identify potential biomarkers associated with heart failure, in particular that fraction containing albumin that is generally removed from serum samples to permit protein biomarker analysis. Analysis of the unfractionated serum, the albuminome, and the depleted serum is also carried out using surface-enhanced laser desorption/ionization (SELDI) and the high molecular weight proteins are monitored by using a Comet macromizer TOF mass spectrometer with a very high mass cryocooled detector.

Experimental and commercial microvolume fluorimeters with rapid temperature control are described. Fluorescence optics adopted from flow cytometry were used to interrogate 1-10-microL samples in glass capillaries. Homogeneous temperature control and rapid change of sample temperatures (10 degrees C/s) were obtained by a circulating air vortex. A prototype 2-color, 32-sample version was constructed with a xenon arc for excitation, separate excitation and emission paths, and photomultiplier tubes for detection. The commercial LightCycler, a 3-color, 24-sample instrument, uses a blue light-emitting diode for excitation, paraxial epi-illumination through the capillary tip and photodiodes for detection. Applications include analyte quantification and nucleic acid melting curves with fluorescent dyes, enzyme assays with fluorescent substrates and techniques that use fluorescence resonance energy transfer. Microvolume capability allows analysis of very small or expensive samples. As an example of one application, rapid cycle DNA amplification was continuously monitored by three different fluorescence techniques, Which included using the double-stranded DNA dye SYBR Green I, a dual-labeled 5'-exonuclease hydrolysis probe, and adjacent fluorescein and Cy5z-labeled hybridization probes. Complete amplification and analysis requires only 10-15 min.