Planar cell polarity proteins mediate ketamine-induced restoration of glutamatergic synapses in prefrontal cortical neurons in a mouse model for chronic stress.

Single administration of low-dose ketamine has both acute and sustained anti-depressant effects. Sustained effect is associated with restoration of glutamatergic synapses in medial prefrontal cortic (mFPC) neurons. Ketamine induced profound changes in a number of molecular pathways in a mouse model for chronic stress. Cell-cell communication analyses predicted that planar-cell-polarity (PCP) signaling was decreased after chronic administration of corticosterone but increased following ketamine administration in most of the excitatory neurons. Similar decrease of PCP signaling in excitatory neurons was predicted in dorsolateral prefrontal cortical (dl-PFC) neurons of patients with major depressive disorder (MDD). We showed that the basolateral amygdala (BLA)-projecting infralimbic prefrontal cortex (IL PFC) neurons regulate immobility time in the tail suspension test and food consumption. Conditionally knocking out Celsr2 and Celsr3 or Prickle2 in the BLA-projecting IL PFC neurons abolished ketamine-induced synapse restoration and behavioral remission. Therefore, PCP proteins in IL PFC-BLA neurons mediate synapse restoration induced by of low-dose ketamine.

A randomized, double-blind, placebo-controlled clinical trial of fluconazole as early empiric treatment of coccidioidomycosis pneumonia (Valley Fever) in adults presenting with community-acquired pneumonia in endemic areas (FLEET-Valley Fever).

INTRODUCTION: Coccidioidomycosis is a fungal infection endemic in the southwestern United States (US). Primary pulmonary coccidioidomycosis (PPC) is a leading cause of community-acquired pneumonia (CAP) in this region, although its diagnosis is often delayed, leading to lag in antifungal treatment and subsequent morbidity. The impact of early empiric antifungal therapy as part of treatment for CAP in endemic areas on clinical outcomes is unknown. METHODS: Phase IV randomized, double-blind, placebo-controlled trial in individuals aged 18 years or older with CAP who met all eligibility criteria in Coccidioides endemic regions in the US. Eligible participants with CAP were randomized to receive either fluconazole (400 mg daily) or matching placebo for 42 days and were subsequently monitored for clinical resolution of their illness. OBJECTIVES: The primary objective was to assess the clinical response of early empiric antifungal therapy with fluconazole through Day 22 in subjects with PPC who were adherent to the study intervention. Secondary objectives included: assessments of the impact of early empiric antifungal therapy with fluconazole through Day 22 and 43 in subjects with PPC regardless of adherence, comparisons of the clinical response and its individual components over time by treatment group in subjects with PPC, assessments of days lost from work or school, hospitalization, and all-cause mortality. DISCUSSION: This trial was halted early due to slow enrollment (72 participants in one year, 33 received fluconazole and 39 received placebo). Of those enrolled, eight (11%) met the study definition of PPC. The study design and challenges are discussed.

Patterns of Care and Treatment Outcomes for Outpatient Daptomycin-Containing Regimens in Osteomyelitis.

BACKGROUND: Use of daptomycin at doses ≥ 6 mg/kg for treatment of osteomyelitis is increasing in clinical practice; unfortunately, limited data are available to guide optimal dosing and duration. The objective of this study was to assess daptomycin dosing and duration regimens for osteomyelitis treatment. METHODS: This was a retrospective, multi-site, cohort study conducted in an integrated healthcare delivery system. Nonpregnant patients ≥ 18 years of age with osteomyelitis diagnosed between November 1, 2003 and June 30, 2011, ≥ 2 weeks outpatient daptomycin therapy, and ≥ 1 month of follow-up were included. Daptomycin doses < 6 mg/kg and ≥ 6 mg/kg at durations of < 6 weeks and ≥ 6 weeks were examined with univariate and multivariate analyses to assess treatment success and all-cause mortality. RESULTS: A total of 247 patients were included, with 39 (15.8%), 37 (15.0%), 107 (43.3%), and 64 (25.9%) receiving < 6 mg/kg and ≥ 6 weeks, < 6 mg/kg and < 6 weeks, ≥ 6 mg/kg and ≥ 6 weeks, and ≥ 6 mg/kg and < 6 weeks of daptomycin therapy, respectively. Patients had a mean age of 58 years and had received prior vancomycin therapy (65.6%). Patients receiving < 6 weeks of therapy were less likely to experience treatment success compared with ≥ 6 weeks (41.5% vs 25.3%, adjusted odds ratio = 0.55; 95% confidence interval = 0.31-0.98) independent of duration. There were no differences across groups in mortality after adjustment. CONCLUSION: In a diverse clinical population, daptomycin for treatment of osteomyelitis of 6 weeks or longer duration was associated with success independent of dose. This finding supports longer treatment with daptomycin as a first-line agent in antimicrobial stewardship initiatives.

Testing for Coccidioidomycosis among Community-Acquired Pneumonia Patients, Southern California, USA1.

We conducted a cohort study to identify characteristics associated with testing for, and testing positive for, coccidioidomycosis among patients with community-acquired pneumonia in southern California, USA. Limited and delayed testing probably leads to underdiagnosis among non-Hispanic black, Filipino, or Hispanic patients and among high-risk groups, including persons in whom antimicrobial drug therapy has failed.

Durability of direct immunofluorescence (DIF) slides stored at room temperature.

BACKGROUND: Prior studies suggested that direct immunofluorescence (DIF) slides can be stored at room temperature. OBJECTIVES: We sought to determine the durability of DIF slides stored at room temperature for 5 years. METHODS: This was a retrospective study of 83 DIF slides archived at room temperature during 2010. The pattern of immunoreactants was compared with those noted in the original report. RESULTS: Loss of reactivity was limited to cases with weak fluorescence at original diagnosis. Loss of IgG was noted in 12.5% of cases, IgA in 12%, C3 in 10%, and IgM in 9.75%. Fibrin showed no loss of reactivity. Preservation of immunofluorescence was not related to site of deposition. Overall, a reliable diagnosis could be made in 75 of 79 archived cases (94.9%). LIMITATIONS: Cases had been archived for periods varying from 4.5 to 5 years. Variations in processing and fluorochromes could affect durability. We have no way of knowing how long slides had been exposed to ultraviolet light at the time of initial examination. CONCLUSION: DIF showed excellent durability in slides kept at room temperature for 5 years.

A Dermatopathologist's Guide to Troubleshooting Immunohistochemistry--Part 2: Troubleshooting Immunohistochemical Tests in the Laboratory.

Unexpected staining patterns can arise from problems occurring in any of the steps required for IHC, some of which are discussed in part I of this CME series. Whether used to differentiate benign from malignant tumors, identify tumor subtypes, subtypes of hematopoietic malignancies, or identifying targets for therapy, the pathologist must be intimately familiar with the potential pitfalls that are inherent in the IHC methodology to troubleshoot problems in the laboratory, and more importantly, when interpreting immunohistochemical staining, to avoid pitfalls of false-positive or false-negative stains.

A Dermatopathologist's Guide to Troubleshooting Immunohistochemistry Part 1: Methods and Pitfalls.

Immunohistochemistry (IHC) is a method by which specific target antigens can be detected in formalin-fixed paraffin-embedded tissue and involves the use of monoclonal or polyclonal antibodies; visualization of specific tissue antigens is achieved through an enzymatic reaction that transforms a colorless chromogen to a colored one. These enzymes may be attached to the antibody through a protein-ligand method (eg, biotin-avidin or biotin-streptavidin) or through a secondary antibody. Epitopes that are masked by protein linkage during formalin fixation are unmasked using a retrieval system that either uses heat (heat-induced epitope retrieval) or proteolytic enzymes (proteolytic-induced epitope retrieval). Part 1 of this review will focus and elaborate on the available methodologies for IHC testing, common problems inherent to each technique, and how they can be resolved. Part 2 will focus on common problems and artifacts encountered during IHC staining, likely causes, and methods for addressing each problem.

Glucose-responsive insulin activity by covalent modification with aliphatic phenylboronic acid conjugates.

Since its discovery and isolation, exogenous insulin has dramatically changed the outlook for patients with diabetes. However, even when patients strictly follow an insulin regimen, serious complications can result as patients experience both hyperglycemic and hypoglycemic states. Several chemically or genetically modified insulins have been developed that tune the pharmacokinetics of insulin activity for personalized therapy. Here, we demonstrate a strategy for the chemical modification of insulin intended to promote both long-lasting and glucose-responsive activity through the incorporation of an aliphatic domain to facilitate hydrophobic interactions, as well as a phenylboronic acid for glucose sensing. These synthetic insulin derivatives enable rapid reversal of blood glucose in a diabetic mouse model following glucose challenge, with some derivatives responding to repeated glucose challenges over a 13-h period. The best-performing insulin derivative provides glucose control that is superior to native insulin, with responsiveness to glucose challenge improved over a clinically used long-acting insulin derivative. Moreover, continuous glucose monitoring reveals responsiveness matching that of a healthy pancreas. This synthetic approach to insulin modification could afford both long-term and glucose-mediated insulin activity, thereby reducing the number of administrations and improving the fidelity of glycemic control for insulin therapy. The described work is to our knowledge the first demonstration of a glucose-binding modified insulin molecule with glucose-responsive activity verified in vivo.

Neuroimaging abnormalities, neurocognitive function, and fatigue in patients with hepatitis C.

OBJECTIVE: This study examined neurologic abnormalities (as measured by proton magnetic resonance spectroscopy imaging and diffusion tensor imaging), neurocognitive performance, and fatigue among a sample of adults with hepatitis C virus (HCV). We hypothesized that HCV+ individuals would demonstrate structural brain abnormalities and neurocognitive compromise consistent with frontostriatal dysfunction as well as increased fatigue compared to controls. METHOD: Participants were 76 individuals diagnosed with HCV and 20 controls who underwent a comprehensive neurocognitive evaluation and clinical assessments. A subset of the HCV+ participants (n = 29) and all controls underwent MRI. RESULTS: Individuals diagnosed with chronic HCV infection demonstrated greater fractional anisotropy in the striatum as well as greater mean diffusivity in the fronto-occiptal fasciculus and external capsule compared to HCV- controls. HCV+ participants also demonstrated lower levels of N-acetylaspartate in bilateral parietal white matter and elevations in myo-inosital (mI) in bilateral frontal white matter compared to HCV- controls (all p values < 0.05). HCV+ participants also demonstrated significantly poorer neuropsychological performance, particularly in processing speed and verbal fluency. HCV+ patients reported higher levels of fatigue than controls, and fatigue was significantly correlated with diffusivity in the superior fronto-occipital fasciculus, elevations in mI in frontal white matter, and overall cognitive performance. CONCLUSIONS: Our results suggest that HCV-associated neurologic complications disrupt frontostriatal structures, which may result in increased fatigue and poorer cognitive performance, particularly in those cognitive domains regulated by frontostriatal regions.

Restriction of the conformational dynamics of the cyclic acyldepsipeptide antibiotics improves their antibacterial activity.

The cyclic acyldepsipeptide (ADEP) antibiotics are a new class of antibacterial agents that kill bacteria via a mechanism that is distinct from all clinically used drugs. These molecules bind and dysregulate the activity of the ClpP peptidase. The potential of these antibiotics as antibacterial drugs has been enhanced by the elimination of pharmacological liabilities through medicinal chemistry efforts. Here, we demonstrate that the ADEP conformation observed in the ADEP-ClpP crystal structure is fortified by transannular hydrogen bonding and can be further stabilized by judicious replacement of constituent amino acids within the peptidolactone core structure with more conformationally constrained counterparts. Evidence supporting constraint of the molecule into the bioactive conformer was obtained by measurements of deuterium-exchange kinetics of hydrogens that were proposed to be engaged in transannular hydrogen bonds. We show that the rigidified ADEP analogs bind and activate ClpP at lower concentrations in vitro. Remarkably, these compounds have up to 1200-fold enhanced antibacterial activity when compared to those with the peptidolactone core structure common to two ADEP natural products. This study compellingly demonstrates how rational modulation of conformational dynamics may be used to improve the bioactivities of natural products.

Investigation of the configurational stabilities of chiral isocyanoacetates in multicomponent reactions.

Isocyanoacetates are uniquely reactive compounds characterized by an ambivalent isocyano functional group and an enolizable α-carbon. It is widely believed that chiral α-substituted isocyanoacetates are configurationally unstable in some synthetically useful isocyanide-based multicomponent reactions. Herein, we demonstrate that chiral isocyanoacetates can be used with minimal to negligible epimerization in a variety of canonical Ugi four-component condensations as well as Joullié-Ugi three-component condensations, reactions that are particularly useful for constructing complex peptide structures in a single synthetic operation.

Coccidioidal meningitis: clinical presentation and management in the fluconazole era.

Despite the advent of new antifungal agents, coccidioidal meningitis (CM) remains a difficult-to-treat condition with significant morbidity and mortality. In this study we directly compare the clinical presentation and management of patients with Coccidioides immitis meningitis in the azole era (after 1980) to that of a cohort of patients from the pre-azole era. We reviewed 30 CM cases seen at 3 Los Angeles hospitals between the years 1993 to 2008 ("2008 cohort") and compared them to 31 patients ("1980 cohort") described by Bouza et al in a previous study. The demographics and clinical presentation of patients in the 2008 cohort were similar to those of the 1980 cohort except for a higher incidence of Hispanic patients (2008: 53% vs. 1980: 6%) and a greater percentage of patients with underlying, predisposing clinical conditions (2008: 66% vs. 1980: 32%). Ten patients in the 2008 cohort had human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), a condition not reported in the earlier study. Laboratory findings were similar between the 2 groups except for a lower incidence of peripheral leukocytosis and eosinophilia in the 2008 group.There were marked differences in drug treatment between the 2 eras. In the 2008 cohort, 29 patients received fluconazole therapy: 13 were treated with fluconazole monotherapy, and 16 received a combination of fluconazole and intravenous amphotericin B. Although almost all patients (29/31) in the 1980 cohort received intrathecal amphotericin B, only 3 patients in the 2008 study received amphotericin B via this route. With respect to complications of CM, a similar percentage of patients in each cohort developed complications such as stroke and hydrocephalus. The 2008 cohort (40%) had similar mortality compared to patients in the 1980 study (39%); survivors in both groups experienced significant impairment of activities of daily living. Although recommended as first-line therapy for CM, azole-based therapies are not curative and do not necessarily prevent complications associated with the disease.CM remains a serious illness with a high rate of morbidity and mortality. Immunocompromised individuals, especially those with HIV/AIDS, are at special risk for CM and represent a greater share of the overall population with this condition. Despite the clear advantages of azole treatment in CM, new therapeutic approaches are needed to provide definitive cure and to reduce the need for long-term suppressive therapy.