Short Signature Gene Sequence to Differentiate Species in Mycobacterium abscessus Group.

Mycobacterium abscessus group (MAG) are rapidly growing acid-fast bacteria that consist of three closely related species: M. abscessus (), (), and (). Differentiation of these species can be difficult but is increasingly requested owing to recent infectious outbreaks and their differential drug resistance.

Recovery and Its Dynamics of Filamentous Fungi from Clinical Specimen Cultures: An Extensive Study.

The culture method remains vital in diagnosing fungal infections, but extensive data-based evaluation of the method, especially for filamentous fungi (molds), is minimal. The purpose of this study was to characterize mold recoveries from fungal cultures and the impact of media and incubation duration. Clinical specimens for fungal cultures were submitted primarily from the eastern and central United States, and mold isolation data were prospectively collected and analyzed.

Retrospective Performance Analyses of over Two Million U.S. QuantiFERON Blood Sample Results.

Both the QuantiFERON-TB Gold Plus (QFT-Plus) and the QuantiFERON-TB Gold In-Tube (QFT-GIT) tests are interferon gamma (IFN-γ) release assays (IGRAs) intended to detect cell-mediated immune responses to Mycobacterium tuberculosis antigens. In this study, we retrospectively analyzed performance data for both the QFT-GIT and QFT-Plus test systems from over 2 million samples. QFT-Plus and QFT-GIT testing was performed as specified in the respective package inserts at 23 Quest Diagnostics sites.

Parkinson's Disease Caregiver Strain in Singapore.

Caregiver strain is recognized globally with Parkinson's disease (PD). Comparatively little is understood about caregiver burden and strain in Asia. To investigate caregiver strain for families living with PD in Singapore, in light of international data.

Current significance of the Mycobacterium chelonae-abscessus group.

Organisms of the Mycobacterium chelonae-abscessus group can be significant pathogens in humans. They produce a number of diseases including acute, invasive and chronic infections, which may be difficult to diagnose correctly. Identification among members of this group is complicated by differentiating at least eleven (11) known species and subspecies and complexity of identification methodologies.

Acid-fast bacterium detection and identification from paraffin-embedded tissues using a PCR-pyrosequencing method.

Aims: Acid-fast bacterium (AFB) identification from formalin-fixed paraffin-embedded (FFPE) tissues is challenging and may not be readily available to the clinical laboratory. A method to detect and identify AFB from FFPE tissues using PCR and pyrosequencing (PCR-Seq) was developed and evaluated.

Methods: The method was validated using spiked cell-clotted paraffin blocks before use with patients' specimens.

Salmeterol Efficacy and Bias in the Activation and Kinase-Mediated Desensitization of β2-Adrenergic Receptors.

Salmeterol is a long-acting β2-adrenergic receptor (β2AR) agonist that is widely used as a bronchodilator for the treatment of persistent asthma and chronic obstructive pulmonary disease in conjunction with steroids. Previous studies demonstrated that salmeterol showed weak efficacy for activation of adenylyl cyclase; however, its efficacy in the complex desensitization of the β2AR remains poorly understood. In this work, we provide insights into the roles played by the G protein-coupled receptor kinase/arrestin and protein kinase A in salmeterol-mediated desensitization through bioluminescence resonance energy transfer (BRET) studies of liganded-β2AR binding to arrestin and through kinetic studies of cAMP turnover.

Biochemical and Cellular Specificity of Peptide Inhibitors of G Protein-Coupled Receptor Kinases.

Identifying novel allosteric inhibitors of G protein-coupled receptor kinases (GRKs) would be of considerable use in limiting both the extent of desensitization of GPCRs as well as downstream positive regulation through GRKs. Several peptides have previously been identified as inhibitors of specific GRKs, but to date there have been few comparisons of the selectivities of these materials on the seven GRKs, modifications to allow cell penetration, or off-target activities. The goal of this study was to determine if a panel of peptides mimicking domains on either GPCRs or GRKs would exhibit selective inhibition of GRKs 2, 5, 6 and 7 phosphorylation of rhodopsin.

Direct detection and identification of acid-fast bacteria from smear-positive broth cultures using a pyrosequencing method.

Broth culture is a standard method for detection of acid-fast bacteria (AFB) (e.g., Mycobacterium and Nocardia) from patient specimens.

Insulin inhibits cardiac contractility by inducing a Gi-biased β2-adrenergic signaling in hearts.

Insulin and adrenergic stimulation are two divergent regulatory systems that may interact under certain pathophysiological circumstances. Here, we characterized a complex consisting of insulin receptor (IR) and β2-adrenergic receptor (β2AR) in the heart. The IR/β2AR complex undergoes dynamic dissociation under diverse conditions such as Langendorff perfusions of hearts with insulin or after euglycemic-hyperinsulinemic clamps in vivo.

Retinoids activate the irritant receptor TRPV1 and produce sensory hypersensitivity.

Retinoids are structurally related derivatives of vitamin A and are required for normal vision as well as cell proliferation and differentiation. Clinically, retinoids are effective in treating many skin disorders and cancers. Application of retinoids evokes substantial irritating side effects, including pain and inflammation; however, the precise mechanisms accounting for the sensory hypersensitivity are not understood.

A summary of meeting proceedings on addressing variability around the cut point in serial interferon-γ release assay testing.

On June 13, 2012, a group of key stakeholders, leaders, and national experts on tuberculosis (TB), occupational health, and laboratory science met in Atlanta, Georgia, to focus national discussion on the higher than expected positive results occurring among low-risk, unexposed healthcare workers undergoing serial testing with interferon-γ release assays (IGRAs). The objectives of the meeting were to present the latest clinical and operational research findings on the topic, to discuss evaluation and treatment algorithms that are emerging in the absence of national guidance, and to develop a consensus on the action steps needed to assist programs and physicians in the interpretation of serial testing IGRA results. This report summarizes its proceedings.

Escherichia coli antimicrobial resistance increased faster among geriatric outpatients compared with adult outpatients in the USA, 2000-10.

Objectives: Few studies have examined Escherichia coli antimicrobial resistance across age groups over time. The objective of this study was to compare urinary E. coli antimicrobial resistance trends among adult and geriatric outpatients from 2000 to 2010.

Klebsiella pneumoniae antimicrobial drug resistance, United States, 1998-2010.

We studied antimicrobial-resistant Klebsiella pneumoniae for 1998-2010 by using data from The Surveillance Network. Susceptibility results (n = 3,132,354) demonstrated significant increases in resistance to all antimicrobial drugs studied, except tetracycline. Cross-resistance among carbapenem-resistant K.

Legal disputes over duties to disclose treatment risks to patients: a review of negligence claims and complaints in Australia.

David Studdert and colleagues identified disputes over informed consent among malpractice claims and serious health care complaints in Australia and provide an analysis of disagreements between patients and doctors over whether particular clinical risks should have been disclosed before treatment.

Legal disputes over informed consent for cosmetic procedures: a descriptive study of negligence claims and complaints in Australia.

Background: Plastic surgeons and other doctors who perform cosmetic procedures face relatively high risks of malpractice claims and complaints. In particular, alleged problems with the consent process abound in this area, but little is known about the clinical circumstances of these cases.

Method: We reviewed 481 malpractice claims and serious health care complaints resolved in Australia between 2002 and 2008 that alleged failures in the informed consent process for cosmetic and other procedures.

Reverse-transcription polymerase chain reaction/pyrosequencing to characterize neuraminidase H275 residue of influenza A 2009 H1N1 virus for rapid and specific detection of the viral oseltamivir resistance marker in a clinical laboratory.

Pandemic 2009 H1N1 is normally susceptible to oseltamivir, but variants harboring the H275Y (CAC → TAC) mutation exhibit resistance. We describe the use of a combined reverse-transcription polymerase chain reaction (RT-PCR)/pyrosequencing approach to identify the H275 residue. A total of 223 specimens were tested with this method: 216 randomly selected clinical specimens positive for 2009 H1N1 and 7 cell-culture supernatants from the Centers for Disease Control and Prevention (CDC; 4 resistant, 3 susceptible 2009 H1N1 strains).

When informed consent goes poorly: a descriptive study of medical negligence claims and patient complaints.

Objective: To describe the frequency, characteristics, and outcomes of medicolegal disputes over informed consent.

Design And Setting: Retrospective review and analysis of negligence claims against doctors insured by Avant Mutual Group Limited and complaints lodged with the Office of the Health Services Commissioner of Victoria that alleged failures in the informed consent process and were adjudicated between 1 January 2002 and 31 December 2008.

Main Outcome Measures: Case frequency (by medical specialty), type of allegation, type of treatment.

Analysis of resistance, cross-resistance and antimicrobial combinations for Pseudomonas aeruginosa isolates from 1997 to 2009.

Pseudomonas aeruginosa is a nosocomial and community-acquired pathogen associated with considerable patient morbidity and mortality. Multidrug resistance in P. aeruginosa is a concern owing to the limited therapeutic options available to treat infections due to this organism.

Methicillin-resistant Staphylococcus aureus resistance to non-beta-lactam antimicrobials in the United States from 1996 to 2008.

We report the resistance rates of Staphylococcus aureus to non-beta-lactam antimicrobials from The Surveillance Network Database-USA (Eurofins-Medinet, Chantilly, VA). Specimens studied were from lower respiratory tract, wounds, and blood. Patients were stratified by age group and patient setting.

Identification of acid-fast bacilli using pyrosequencing analysis.

Pyrosequence identification of 117 isolates of acid-fast bacilli (AFB) was compared to both routine phenotypic methods and Sanger sequencing. Two (2) vendor-provided pyrosequencing primers specific for AFB were used for the study. Pyrosequence analysis correctly identified 114 (98%) of the tested 117 AFB isolates.

Quantitative modeling of GRK-mediated beta2AR regulation.

We developed a unified model of the GRK-mediated beta2 adrenergic receptor (beta2AR) regulation that simultaneously accounts for six different biochemical measurements of the system obtained over a wide range of agonist concentrations. Using a single deterministic model we accounted for (1) GRK phosphorylation in response to various full and partial agonists; (2) dephosphorylation of the GRK site on the beta2AR; (3) beta2AR internalization; (4) recycling of the beta2AR post isoproterenol treatment; (5) beta2AR desensitization; and (6) beta2AR resensitization. Simulations of our model show that plasma membrane dephosphorylation and recycling of the phosphorylated receptor are necessary to adequately account for the measured dephosphorylation kinetics.

Role for the regulator of G-protein signaling homology domain of G protein-coupled receptor kinases 5 and 6 in beta 2-adrenergic receptor and rhodopsin phosphorylation.

Phosphorylation of G protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) is a major mechanism of desensitization of these receptors. GPCR activation of GRKs involves an allosteric site on GRKs distinct from the catalytic site. Although recent studies have suggested an important role of the N- and C-termini and domains surrounding the kinase active site in allosteric activation, the nature of that site and the relative roles of the RH domain in particular remain unknown.