Background: The usefulness of tracheostomy has been questioned in patients with COVID-19 and prolonged invasive mechanical ventilation (IMV).
Aim: To compare the 90-day mortality rate of patients who underwent a tracheostomy due prolonged IMV with those that did not receive this procedure.
Material And Methods: We studied a historical cohort of 92 patients with COVID-19 and prolonged IMV (> 10 days).
Previous reports from our laboratory disclosed the structure and activity of a novel 1H-pyrazolo[4,3-b]pyridine-3-amine scaffold (VU8506) which showed excellent potency, selectivity and in vivo efficacy in preclinical rodent models of Parkinson's disease. Unfortunately, this compound suffered from significant CYP1A2 induction as measured through upstream AhR activation (125-fold) and thus was precluded from further advancement in chronic studies. Herein, we report a new scaffold developed recently which was systematically studied in order to mitigate the CYP1A2 liabilities presented in the earlier scaffolds.
View Article and Find Full Text PDFRett syndrome (RTT) is a neurodevelopmental disorder caused by mutations in the () gene. The cognitive impairments seen in mouse models of RTT correlate with deficits in long-term potentiation (LTP) at Schaffer collateral (SC)-CA1 synapses in the hippocampus. Metabotropic glutamate receptor 7 (mGlu) is the predominant mGlu receptor expressed presynaptically at SC-CA1 synapses in adult mice, and its activation on GABAergic interneurons is necessary for induction of LTP.
View Article and Find Full Text PDFRett syndrome (RS) is a neurodevelopmental disorder that shares many symptomatic and pathological commonalities with idiopathic autism. Alterations in protein synthesis-dependent synaptic plasticity (PSDSP) are a hallmark of a number of syndromic forms of autism; in the present work, we explore the consequences of disruption and rescue of PSDSP in a mouse model of RS. We report that expression of a key regulator of synaptic protein synthesis, the metabotropic glutamate receptor 5 (mGlu) protein, is significantly reduced in both the brains of RS model mice and in the motor cortex of human RS autopsy samples.
View Article and Find Full Text PDFMetabotropic glutamate receptor 7 (mGlu7) is a member of the group III mGlu receptors (mGlus), encompassed by mGlu4, mGlu6, mGlu7, and mGlu8. mGlu7 is highly expressed in the presynaptic active zones of both excitatory and inhibitory synapses, and activation of the receptor regulates the release of both glutamate and GABA. mGlu7 is thought to be a relevant therapeutic target for a number of neurological and psychiatric disorders, and polymorphisms in the GRM7 gene have been linked to autism, depression, ADHD, and schizophrenia.
View Article and Find Full Text PDFThe objective of this study was to evaluate the efficacy of three off-loading techniques to heal diabetic foot wounds: total contact casts (TCCs), healing sandals (HSs) and a removable boot with a shear-reducing foot bed (SRB). This was a 12-week, single-blinded randomised clinical trial with three parallel treatment groups of adults with diabetes and a foot ulcer (n = 73). Ulcer healing was defined as full reepithelialisation with no drainage.
View Article and Find Full Text PDFMetabotropic glutamate (mGlu) receptors play important roles in regulating CNS function and are known to function as obligatory dimers. Although recent studies have suggested heterodimeric assembly of mGlu receptors in vitro, the demonstration that distinct mGlu receptor proteins can form heterodimers or hetero-complexes with other mGlu subunits in native tissues, such as neurons, has not been shown. Using biochemical and pharmacological approaches, we demonstrate here that mGlu2 and mGlu4 form a hetero-complex in native rat and mouse tissues which exhibits a distinct pharmacological profile.
View Article and Find Full Text PDFFood Addit Contam Part A Chem Anal Control Expo Risk Assess
April 2014
The aim of this study was to analyse and determine the composition of paralytic shellfish poisoning (PSP) toxins and lipophilic toxins in the Region of Aysén, Chile, in wild endemic mussels (Mytilus chilensis, Venus antiqua, Aulacomya ater, Choromytilus chorus, Tagelus dombeii and Gari solida) and in two endemic carnivorous molluscs species (Concholepas concholepas and Argobuccinum ranelliforme). PSP-toxin contents were determined by using HPLC with fluorescence detection, while lipophilic toxins were determined by using LC-MS/MS. Mean concentrations for the total of PSP toxins were in the range 55-2505 μg saxitoxin-equivalent/100 g.
View Article and Find Full Text PDFMetabotropic glutamate receptors (mGlus) are a group of Family C Seven Transmembrane Spanning Receptors (7TMRs) that play important roles in modulating signaling transduction, particularly within the central nervous system. mGlu(4) belongs to a subfamily of mGlus that is predominantly coupled to G(i/o) G proteins. We now report that the ubiquitous autacoid and neuromodulator, histamine, induces substantial glutamate-activated calcium mobilization in mGlu(4)-expressing cells, an effect which is observed in the absence of co-expressed chimeric G proteins.
View Article and Find Full Text PDFIntroduction: Kawasaki disease (KD) is a serious disease in children due to its potential complications and sequelae if not promptly and adequately managed.
Objectives: To describe clinical and epidemiological characteristics of children hospitalized due to KD at a tertiary care center and identify risk factors for poor outcome.
Patients And Methods: Retrospective and descriptive study of 32 medical records of patients hospitalized with diagnosis of KD at a tertiary care center of Santiago, Chile between February 1999 and May 2007.
Herein we report the discovery and SAR of a novel antagonist of metabotropic glutamate receptor 4 (mGlu(4)). The antagonist was discovered via a molecular switch from a closely related mGlu(4) positive allosteric modulator (PAM). This antagonist (VU0448383) displays an IC(50) value of 8.
View Article and Find Full Text PDFThere is an increasing amount of literature data showing the positive effects on preclinical antiparkinsonian rodent models with selective positive allosteric modulators of metabotropic glutamate receptor 4 (mGlu(4)). However, most of the data generated utilize compounds that have not been optimized for druglike properties, and as a consequence, they exhibit poor pharmacokinetic properties and thus do not cross the blood-brain barrier. Herein, we report on a series of N-4-(2,5-dioxopyrrolidin-1-yl)phenylpicolinamides with improved PK properties with excellent potency and selectivity as well as improved brain exposure in rodents.
View Article and Find Full Text PDFUsing a functional high-throughput screening (HTS) and subsequent solution-phase parallel synthesis approach, we have discovered a novel series of positive allosteric modulators for mGlu₄, a G-protein coupled receptor. This series is comprised of a homopiperazine central core. The solution-phase parallel synthesis and SAR of analogs derived from this series will be presented.
View Article and Find Full Text PDFHerein we report the discovery, synthesis, and evaluation of a series of N-(4-acetamido)-phenylpicolinamides as positive allosteric modulators of mGlu(4). Compounds from the series show submicromolar potency at both human and rat mGlu(4). In addition, pharmacokinetic studies utilizing subcutaneous dosing demonstrated good brain exposure in rats.
View Article and Find Full Text PDFDespite the availability of newer therapeutic interventions to improve clinical outcome in patients with Systemic Lupus Erythematosus (SLE), the incidence of infections as a cause of morbidity and mortality has not changed over the past 30 years. SLE itself increases the risk of infection, due to genetic (complement deficiencies) and acquired factors such as functional asplenia (humoral immunodepression) and the use of immunosuppressive drugs. These medications increase the risk of opportunistic infections that are associated with an altered cellular immune response.
View Article and Find Full Text PDFWe report the synthesis and evaluation of a series of heterobiaryl amides as positive allosteric modulators of mGluR4. Compounds 9b and 9c showed submicromolar potency at both human and rat mGluR4. In addition, both 9b and 9c were shown to be centrally penetrant in rats using nontoxic vehicles, a major advance for the mGluR4 field.
View Article and Find Full Text PDFObjective: The purpose of this study was to evaluate the effectiveness of a temperature monitoring instrument to reduce the incidence of foot ulcers in individuals with diabetes who have a high risk for lower extremity complications.
Research Design And Methods: In this physician-blinded, randomized, 15-month, multicenter trial, 173 subjects with a previous history of diabetic foot ulceration were assigned to standard therapy, structured foot examination, or enhanced therapy groups. Each group received therapeutic footwear, diabetic foot education, and regular foot care.
Streptococcus pneumoniae is a rarely recognized cause of neonatal sepsis and/or meningitis, but it is associated with substantial morbidity and mortality. Traditionally, S. pneumoniae is identified in the laboratory by demonstrating susceptibility to optochin.
View Article and Find Full Text PDFAm J Physiol Renal Physiol
February 2006
Regulation of the constitutively expressed type 2 bradykinin (B2) receptor, which mediates the principal actions of bradykinin, occurs at multiple levels. The goal of the current study was to determine whether the human B2 3'-untranslated region (UTR) has effects on gene expression, with particular focus on the variable number of tandem repeats (B2-VNTR) polymorphic portion of the 3'-UTR and its flanking AU-rich elements (AREs). When inserted downstream of the luciferase coding region of the pGL3-Promoter vector, the B2-VNTR reduced reporter gene activity by 85% compared with pGL3-Promoter alone (promoter control; P < 0.
View Article and Find Full Text PDFObjective: This study was designed to measure pressure and shear reduction of a novel insole design.
Methods: We compared three multilayer viscoelastic insoles to a novel insole design (Glide-Soft, Xilas Medical, Inc., San Antonio, TX).
Objective: To evaluate the effectiveness of at-home infrared temperature monitoring as a preventative tool in individuals at high risk for diabetes-related lower-extremity ulceration and amputation.
Research Design And Methods: Eighty-five patients who fit diabetic foot risk category 2 or 3 (neuropathy and foot deformity or previous history of ulceration or partial foot amputation) were randomized into a standard therapy group (n = 41) or an enhanced therapy group (n = 44). Standard therapy consisted of therapeutic footwear, diabetic foot education, and regular foot evaluation by a podiatrist.
High-risk-type human papillomavirus DNA sequences are found in a high percentage of carcinomas from the uterine-cervix, with the viral E1-E2 gene region usually disrupted and the E6 and E7 oncoproteins consistently expressed. The E2 protein is known to repress early transcription from genital HPV promoters having a proximal E2 binding site (E2BS) close to the TATA box. On the contrary, the E2 protein activates cutaneous early promoters having a longer distance between these sites.
View Article and Find Full Text PDFThe physical state of the human papillomavirus (HPV) genome is usually different in malignant lesions of the skin, in which it is generally found in episomal form, and genital mucosa, in which it is frequently integrated with disruption of the E2 gene. Using chimeric or natural HPV promoters in the presence of the bovine papillomavirus type 1 E2 gene product, we observed transcription activation or repression, depending on the distance of E2-binding motifs from the start site. We found a clear difference in the positions of E2-binding motifs in cutaneous and genital HPVs that may partly explain the selective pressure for genome integration of genital HPV types in malignant lesions.
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