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1.
Cell ; 182(5): 1170-1185.e9, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32795412

RESUMO

Loss of the gene (Fmr1) encoding Fragile X mental retardation protein (FMRP) causes increased mRNA translation and aberrant synaptic development. We find neurons of the Fmr1-/y mouse have a mitochondrial inner membrane leak contributing to a "leak metabolism." In human Fragile X syndrome (FXS) fibroblasts and in Fmr1-/y mouse neurons, closure of the ATP synthase leak channel by mild depletion of its c-subunit or pharmacological inhibition normalizes stimulus-induced and constitutive mRNA translation rate, decreases lactate and key glycolytic and tricarboxylic acid (TCA) cycle enzyme levels, and triggers synapse maturation. FMRP regulates leak closure in wild-type (WT), but not FX synapses, by stimulus-dependent ATP synthase ß subunit translation; this increases the ratio of ATP synthase enzyme to its c-subunit, enhancing ATP production efficiency and synaptic growth. In contrast, in FXS, inability to close developmental c-subunit leak prevents stimulus-dependent synaptic maturation. Therefore, ATP synthase c-subunit leak closure encourages development and attenuates autistic behaviors.


Assuntos
Trifosfato de Adenosina/metabolismo , Síndrome do Cromossomo X Frágil/metabolismo , Subunidades Proteicas/metabolismo , Animais , Linhagem Celular , Ciclo do Ácido Cítrico/fisiologia , Fibroblastos/metabolismo , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Células HEK293 , Humanos , Camundongos , Neurônios/metabolismo , RNA Mensageiro , Sinapses/metabolismo
2.
Emerg Infect Dis ; 29(12): 2569-2572, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37987597

RESUMO

Neurocysticercosis is almost exclusively caused by Taenia solium tapeworms. We describe a case of neurocysticercosis in Switzerland caused by infection with Taenia martis, the marten tapeworm, and review all 5 published cases of human infection with the marten tapeworm. In epidemiologically nonplausible cases of neurocysticercosis, zoonotic spillover infections should be suspected.


Assuntos
Mustelidae , Neurocisticercose , Taenia solium , Taenia , Animais , Humanos , Neurocisticercose/diagnóstico por imagem , Suíça
3.
Eur J Vasc Endovasc Surg ; 64(6): 595-601, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35977695

RESUMO

OBJECTIVE: Dissection of the carotid artery (CaAD) may result in aneurysm formation. The present study was undertaken to evaluate the time of onset of post-dissection extracranial carotid artery aneurysms (ECAA) following CaAD, and to analyse independent risk factors for the development of these aneurysms. METHODS: From four European stroke centres, 360 patients with extracranial CaAD were included. The time between the estimated dissection onset and aneurysm formation was analysed, and the clinical risk factors increasing the probability of aneurysm were assessed. RESULTS: The median duration of follow up was 5.2 months (range 0 - 24 months). A total of 75 post-dissection ECAAs were identified in 70 patients (19.4%, 95% confidence interval [CI] 15.7 - 23.8). In 52 of 70 (74%) patients, the ECAA was diagnosed at the initial clinical work up of CaAD diagnosis, with the median estimated time of dissection onset to ECAA diagnosis being six days (interquartile range [IQR] 0 - 25). In the remaining 18 (26%) patients who had normal carotid arteries at the initial imaging, the aneurysm diagnosis was made a median of 6.2 months (189 days) from the original imaging (IQR 128 - 198). A Cox proportional hazards model showed that both multiple artery dissections (hazard ratio [HR] 2.58, 95% CI 1.54 - 4.33) and arterial tortuosity (HR 1.79, 95% CI 1.08 - 2.95) were associated with presence of ipsilateral ECAA. CONCLUSION: This post hoc cohort analysis showed substantially delayed development of ipsilateral ECAA in patients with CaAD, months after baseline. Multiple dissections and arterial tortuosity are associated with the presence of ECAA and can be used in future prediction models of ECAA development in patients with CaAD.


Assuntos
Aneurisma , Dissecção Aórtica , Doenças das Artérias Carótidas , Humanos , Dilatação , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/cirurgia , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Artérias Carótidas , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia
4.
J Phycol ; 56(1): 135-145, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31639884

RESUMO

Melting summer snow in the Austrian Alps exhibited a yellowish bloom that was mainly comprised of an unidentified unicellular chrysophyte. Molecular data (18S rRNA and rbcL genes) showed a close relationship to published sequences from an American pond alga formerly identified as Kremastochrysis sp. The genera Kremastochrysis and Kremastochrysopsis are morphologically distinguished by the number of flagella observed with the light microscope, and therefore we assigned the Austrian snow alga and an American pond alga to the genus Kremastochrysopsis. Transmission and scanning electron microscopy revealed that swimming cells had two flagella oriented in opposite directions, typical for the Hibberdiales. Molecular phylogenetic analyses showed that both new species were closely related to Hibberdia. Kremastochrysopsis ocellata, the type species and only known species, has two chloroplasts per cell and the zoospores have red eyespots. Our two organisms had only a single chloroplast and no zoospore eyespot, but their gene sequences differed substantially. Therefore, we described two new species, Kremastochrysopsis austriaca sp. nov and Kremstochrysopsis americana sp. nov. When grown in culture, both taxa showed a characteristic hyponeustonic growth (hanging below the water surface), whereas older immotile cells grew at the bottom of the culture vessel. Ecologically, Kremastochrysopsis austriaca sp. nov., which caused snow discolorations, had no close phylogenetic relationships to other psychrophilic chrysophytes, for example, Chromulina chionophilia, Hydrurus sp., and Ochromonas-like flagellates.


Assuntos
Cloroplastos , Chrysophyta , Áustria , Filogenia , RNA Ribossômico 16S , RNA Ribossômico 18S , Análise de Sequência de DNA
5.
Nano Lett ; 19(2): 643-651, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30525694

RESUMO

To support the emerging battle against antimicrobial resistance (AMR), detection methods that allow fast and accurate antimicrobial susceptibility testing (AST) are urgently needed. The early identification and application of an appropriate antibiotic treatment leads to lower mortality rates and substantial cost savings and prevents the development of resistant pathogens. In this work, we present a diffraction-based method, which is capable of quantitative bacterial growth, mobility, and susceptibility measurements. The method is based on the temporal analysis of the intensity of a light diffraction peak, which arises due to interference at a periodic pattern of gold nanostructures. The presence of bacteria disturbs the constructive interference, leading to an intensity decrease and thus allows the monitoring of bacterial growth in very low volumes. We demonstrate the direct correlation of the decrease in diffraction peak intensity with bacterial cell number starting from single cells and show the capability for rapid high-throughput AST measurements by determining the minimum inhibitory concentration for three different antimicrobials in less than 2-3 h as well as the susceptibility in less than 30-40 min. Furthermore, bacterial mobility is obtained from short-term fluctuations of the diffraction peak intensity and is shown to decrease by a factor of 3 during bacterial attachment to a surface. This multiparameter detection method allows for rapid AST of planktonic and of biofilm-forming bacterial strains in low volumes and in real-time without the need of high initial cell numbers.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana/instrumentação , Análise de Célula Única/instrumentação , Bactérias/citologia , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Desenho de Equipamento , Escherichia coli/citologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Humanos , Testes de Sensibilidade Microbiana/economia , Testes de Sensibilidade Microbiana/métodos , Análise de Célula Única/economia , Análise de Célula Única/métodos , Fatores de Tempo
7.
Mol Pharmacol ; 87(1): 1-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25332381

RESUMO

Inefficiency of oxidative phosphorylation can result from futile leak conductance through the inner mitochondrial membrane. Stress or injury may exacerbate this leak conductance, putting cells, and particularly neurons, at risk of dysfunction and even death when energy demand exceeds cellular energy production. Using a novel method, we have recently described an ion conductance consistent with mitochondrial permeability transition pore (mPTP) within the c-subunit of the ATP synthase. Excitotoxicity, reactive oxygen species-producing stimuli, or elevated mitochondrial matrix calcium opens the channel, which is inhibited by cyclosporine A and ATP/ADP. Here we show that ATP and the neuroprotective drug dexpramipexole (DEX) inhibited an ion conductance consistent with this c-subunit channel (mPTP) in brain-derived submitochondrial vesicles (SMVs) enriched for F1FO ATP synthase (complex V). Treatment of SMVs with urea denatured extramembrane components of complex V, eliminated DEX- but not ATP-mediated current inhibition, and reduced binding of [(14)C]DEX. Direct effects of DEX on the synthesis and hydrolysis of ATP by complex V suggest that interaction of the compound with its target results in functional conformational changes in the enzyme complex. [(14)C]DEX bound specifically to purified recombinant b and oligomycin sensitivity-conferring protein subunits of the mitochondrial F1FO ATP synthase. Previous data indicate that DEX increased the efficiency of energy production in cells, including neurons. Taken together, these studies suggest that modulation of a complex V-associated inner mitochondrial membrane current is metabolically important and may represent an avenue for the development of new therapeutics for neurodegenerative disorders.


Assuntos
Benzotiazóis/farmacologia , Ciclosporina/farmacologia , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Encéfalo/citologia , Encéfalo/enzimologia , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Poro de Transição de Permeabilidade Mitocondrial , Pramipexol
8.
Mol Neurobiol ; 61(4): 2430-2445, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37889366

RESUMO

The ability of monkeys and rats to carry out spatial working memory tasks has been shown to depend on the persistent firing of pyramidal cells in the prefrontal cortex (PFC), arising from recurrent excitatory connections on dendritic spines. These spines express hyperpolarization-activated cyclic nucleotide-gated (HCN) channels whose open state is increased by cAMP signaling, and which markedly alter PFC network connectivity and neuronal firing. In traditional neural circuits, activation of these non-selective cation channels leads to neuronal depolarization and increased firing rate. Paradoxically, cAMP activation of HCN channels in PFC pyramidal cells reduces working memory-related neuronal firing. This suggests that activation of HCN channels may hyperpolarize rather than depolarize these neurons. The current study tested the hypothesis that Na+ influx through HCN channels activates Slack Na+-activated K+ (KNa) channels to hyperpolarize the membrane. We have found that HCN and Slack KNa channels co-immunoprecipitate in cortical extracts and that, by immunoelectron microscopy, they colocalize at postsynaptic spines of PFC pyramidal neurons. A specific blocker of HCN channels, ZD7288, reduces KNa current in pyramidal cells that express both HCN and Slack channels, but has no effect on KNa currents in an HEK cell line expressing Slack without HCN channels, indicating that blockade of HCN channels in neurons reduces K+ current indirectly by lowering Na+ influx. Activation of HCN channels by cAMP in a cell line expressing a Ca2+ reporter results in elevation of cytoplasmic Ca2+, but the effect of cAMP is reversed if the HCN channels are co-expressed with Slack channels. Finally, we used a novel pharmacological blocker of Slack channels to show that inhibition of Slack in rat PFC improves working memory performance, an effect previously demonstrated for blockers of HCN channels. Our results suggest that the regulation of working memory by HCN channels in PFC pyramidal neurons is mediated by an HCN-Slack channel complex that links activation HCN channels to suppression of neuronal excitability.


Assuntos
Memória de Curto Prazo , Células Piramidais , Animais , Ratos , Canais de Cátion Regulados por Nucleotídeos Cíclicos , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Memória de Curto Prazo/fisiologia , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Células Piramidais/metabolismo
9.
Biophys J ; 105(5): 1208-16, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-24010664

RESUMO

Von Willebrand Factor (VWF) is a multimeric protein crucial for hemostasis. Under shear flow, it acts as a mechanosensor responding with a size-dependent globule-stretch transition to increasing shear rates. Here, we quantify for the first time, to our knowledge, the size distribution of recombinant VWF and VWF-eGFP using a multilateral approach that involves quantitative gel analysis, fluorescence correlation spectroscopy, and total internal reflection fluorescence microscopy. We find an exponentially decaying size distribution of multimers for recombinant VWF as well as for VWF derived from blood samples in accordance with the notion of a step-growth polymerization process during VWF biosynthesis. The distribution is solely described by the extent of polymerization, which was found to be reduced in the case of the pathologically relevant mutant VWF-IIC. The VWF-specific protease ADAMTS13 systematically shifts the VWF size distribution toward smaller sizes. This dynamic evolution is monitored using fluorescence correlation spectroscopy and compared to a computer simulation of a random cleavage process relating ADAMTS13 concentration to the degree of VWF breakdown. Quantitative assessment of VWF size distribution in terms of an exponential might prove to be useful both as a valuable biophysical characterization and as a possible disease indicator for clinical applications.


Assuntos
Fator de von Willebrand/química , Proteínas ADAM/metabolismo , Proteína ADAMTS13 , Humanos , Multimerização Proteica , Estrutura Quaternária de Proteína , Proteólise , Espectrometria de Fluorescência , Fator de von Willebrand/metabolismo
11.
Biochem Pharmacol ; 208: 115413, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36646291

RESUMO

A number of mutations to members of several CNS potassium (K) channel families have been identified which result in rare forms of neonatal onset epilepsy, or syndromes of which one prominent characteristic is a form of epilepsy. Benign Familial Neonatal Convulsions or Seizures (BFNC or BFNS), also referred to as Self-Limited Familial Neonatal Epilepsy (SeLNE), results from mutations in 2 members of the KV7 family (KCNQ) of K channels; while generally self-resolving by about 15 weeks of age, these mutations significantly increase the probability of generalized seizure disorders in the adult, in some cases they result in more severe developmental syndromes. Epilepsy of Infancy with Migrating Focal Seizures (EIMSF), or Migrating Partial Seizures of Infancy (MMPSI), is a rare severe form of epilepsy linked primarily to gain of function mutations in a member of the sodium-dependent K channel family, KCNT1 or SLACK. Finally, KCNMA1 channelopathies, including Liang-Wang syndrome (LIWAS), are rare combinations of neurological symptoms including seizure, movement abnormalities, delayed development and intellectual disabilities, with Liang-Wang syndrome an extremely serious polymalformative syndrome with a number of neurological sequelae including epilepsy. These are caused by mutations in the pore-forming subunit of the large-conductance calcium-activated K channel (BK channel) KCNMA1. The identification of these rare but significant channelopathies has resulted in a resurgence of interest in their treatment by direct pharmacological or genetic modulation. We will briefly review the genetics, biophysics and pharmacology of these K channels, their linkage with the 3 syndromes described above, and efforts to more effectively target these syndromes.


Assuntos
Canalopatias , Epilepsia Neonatal Benigna , Epilepsia , Recém-Nascido , Adulto , Humanos , Canalopatias/genética , Canalopatias/terapia , Síndrome , Epilepsia/tratamento farmacológico , Epilepsia/genética , Epilepsia Neonatal Benigna/genética , Mutação , Canais de Cálcio/genética , Canais de Potássio Ativados por Sódio/genética , Proteínas do Tecido Nervoso/metabolismo
12.
Adv Neurobiol ; 30: 255-285, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36928854

RESUMO

CNS diseases, including psychiatric disorders, represent a significant opportunity for the discovery and development of new drugs and therapeutic treatments with the potential to have a significant impact on human health. CNS diseases, however, present particular challenges to therapeutic discovery efforts, and psychiatric diseases/disorders may be among the most difficult. With specific exceptions such as psychostimulants for ADHD, a large number of psychiatric patients are resistant to existing treatments. In addition, clinicians have no way of knowing which psychiatric patients will respond to which drugs. By definition, psychiatric diagnoses are syndromal in nature; determinations of efficacy are often self-reported, and drug discovery is largely model-based. While such models of psychiatric disease are amenable to screening for new drugs, whether cellular or whole-animal based, they have only modest face validity and, more importantly, predictive validity. Multiple academic, pharmaceutical industry, and government agencies are dedicated to the translation of new findings about the neurobiology of major psychiatric disorders into the discovery and advancement of novel therapies. The collaboration of these agencies provide a pathway for developing new therapeutics. These efforts will be greatly helped by recent advances in understanding the genetic bases of psychiatric disorders, the ongoing search for diagnostic and therapy-responsive biomarkers, and the validation of new animal models.


Assuntos
Transtornos Mentais , Animais , Humanos , Transtornos Mentais/tratamento farmacológico , Biomarcadores
13.
Indian J Occup Environ Med ; 27(1): 59-66, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303989

RESUMO

Context: The contemporary workplace creates a challenge toward physicians and their teams. They are forced into a situation, in which to be competitive they must have skills outside of their medical specialty, such as health management, pedagogy, and information and communication technologies. Aim: To analyze the level of stress and burnout among the medical employees in the hospital care. Settings and Design: Healthcare professionals from three private, municipal, and regional hospitals filled a questionnaire in the time period January-March 2021. Methods and Material: An adapted Maslach Burnout Inventory 55 question questionnaire was used and analyzed. Statistical Analysis Used: One-way ANOVA, correlation, and multiple regression analysis in SPSS. Results: We identified high levels of emotional exhaustion (>62% report high signs or above), high levels of depersonalization (>70% report signs of depersonalization), and low levels of personal accomplishment (<39% have below average sense of achievements). Conclusions: Despite the physicians and their teams reporting high levels of workload and stress, the satisfaction from work has not diminished and the evaluation for the quality of provided work is still high. Additional research into the topic is required with focus on comparison between hospital physicians and primary care physicians.

14.
Res Sq ; 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37205397

RESUMO

The ability of monkeys and rats to carry out spatial working memory tasks has been shown to depend on the persistent firing of pyramidal cells in the prefrontal cortex (PFC), arising from recurrent excitatory connections on dendritic spines. These spines express hyperpolarization-activated cyclic nucleotide-gated (HCN) channels whose open state is increased by cAMP signaling, and which markedly alter PFC network connectivity and neuronal firing. In traditional neural circuits, activation of these non-selective cation channels leads to neuronal depolarization and increased firing rate. Paradoxically, cAMP activation of HCN channels in PFC pyramidal cells reduces working memory-related neuronal firing. This suggests that activation of HCN channels may hyperpolarize rather than depolarize these neurons. The current study tested the hypothesis that Na+ influx through HCN channels activates Slack Na+-activated K+ (KNa) channels to hyperpolarize the membrane. We have found that HCN and Slack KNa channels coimmunoprecipitate in cortical extracts and that, by immunoelectron microscopy, they colocalize at postsynaptic spines of PFC pyramidal neurons. A specific blocker of HCN channels, ZD7288, reduces KNa current in pyramidal cells that express both HCN and Slack channels, but has no effect on KNa currents in an HEK cell line expressing Slack without HCN channels, indicating that blockade of HCN channels in neurons reduces K+ +current indirectly by lowering Na+ influx. Activation of HCN channels by cAMP in a cell line expressing a Ca2+ reporter results in elevation of cytoplasmic Ca2+, but the effect of cAMP is reversed if the HCN channels are co-expressed with Slack channels. Finally, we used a novel pharmacological blocker of Slack channels to show that inhibition of Slack in rat PFC improves working memory performance, an effect previously demonstrated for blockers of HCN channels. Our results suggest that the regulation of working memory by HCN channels in PFC pyramidal neurons is mediated by an HCN-Slack channel complex that links activation HCN channels to suppression of neuronal excitability.

15.
Neurosurgery ; 92(2): 370-381, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36469672

RESUMO

BACKGROUND: Very small anterior communicating artery aneurysms (vsACoA) of <5 mm in size are detected in a considerable number of patients with aneurysmal subarachnoid hemorrhage (aSAH). Single-center studies report that vsACoA harbor particular risks when treated. OBJECTIVE: To assess the clinical and radiological outcome(s) of patients with aSAH diagnosed with vsACoA after aneurysm treatment and at discharge. METHODS: Information on n = 1868 patients was collected in the Swiss Subarachnoid Hemorrhage Outcome Study registry between 2009 and 2014. The presence of a new focal neurological deficit at discharge, functional status (modified Rankin scale), mortality rates, and procedural complications (in-hospital rebleeding and presence of a new stroke on computed tomography) was assessed for vsACoA and compared with the results observed for aneurysms in other locations and with diameters of 5 to 25 mm. RESULTS: This study analyzed n = 1258 patients with aSAH, n = 439 of which had a documented ruptured ACoA. ACoA location was found in 38% (n = 144/384) of all very small ruptured aneurysms. A higher in-hospital bleeding rate was found in vsACoA compared with non-ACoA locations (2.8 vs 2.1%), especially when endovascularly treated (2.1% vs 0.5%). In multivariate analysis, aneurysm size of 5 to 25 mm, and not ACoA location, was an independent risk factor for a new focal neurological deficit and a higher modified Rankin scale at discharge. Neither very small aneurysm size nor ACoA location was associated with higher mortality rates at discharge or the occurrence of a peri-interventional stroke. CONCLUSION: Very small ruptured ACoA have a higher in-hospital rebleeding rate but are not associated with worse morbidity or mortality.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Adulto , Humanos , Criança , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Hemorragia Subaracnóidea/etiologia , Resultado do Tratamento , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Radiografia
16.
Adv Pharmacol ; 94: 213-254, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35659373

RESUMO

Glucagon-like peptide-1 (GLP-1) receptor agonists are extensively used in type 2 diabetic patients for the effective control of hyperglycemia. It is now clear from outcomes trials that this class of drugs offers important additional benefits to these patients due to reducing the risk of developing major adverse cardiac events (MACE). This risk reduction is, in part, due to effective glycemic control in patients; however, the various outcomes trials, further validated by subsequent meta-analysis of the outcomes trials, suggest that the risk reduction in MACE is also dependent on glycemic-independent mechanisms operant in cardiovascular tissues. These glycemic-independent mechanisms are likely mediated by GLP-1 receptors found throughout the cardiovascular system and by the complex signaling cascades triggered by the binding of agonists to the G-protein coupled receptors. This heterogeneity of signaling pathways underlying different downstream effects of GLP-1 agonists, and the discovery of biased agonists favoring specific signaling pathways, may have import in the future treatment of MACE in these patients. We review the evidence supporting the glycemic-independent evidence for risk reduction of MACE by the GLP-1 receptor agonists and highlight the putative mechanisms underlying these benefits. We also comment on the different signaling pathways which appear important for mediating these effects.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Diabetes Mellitus Tipo 2 , Doenças Cardiovasculares/tratamento farmacológico , Sistema Cardiovascular/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Hipoglicemiantes/uso terapêutico
17.
ACS Omega ; 7(43): 39097-39106, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36340178

RESUMO

Monitoring the anti-epileptic drug carbamazepine (CBZ) is crucial for proper dosing, optimizing a patient's clinical outcome, and managing their medication regimen. Due to its narrow therapeutic window and concentration-related toxicity, CBZ is prescribed and monitored in a highly personalized manner. We report an electrochemical conformation-changing aptasensor with two assay formats: a 30 min assay for routine monitoring and a 5 min assay for rapid emergency testing. To enable "sample-to-answer" testing, a de novo CBZ aptamer (K d < 12 nM) with conformational switching due to a G-quadruplex motif was labeled with methylene blue and immobilized on a gold electrode. The electrode fabrication and detection conditions were optimized using electrochemical techniques and visualized by atomic force microscopy (AFM). The aptasensor performance, including reproducibility, stability, and interference, was characterized using electrochemical impedance spectroscopy and voltammetry techniques. The aptasensor exhibited a wide dynamic range in buffer (10 nM to 100 µM) with limits of detection of 1.25 and 1.82 nM for the 5 and 30 min assays, respectively. The clinical applicability is demonstrated by detecting CBZ in finger prick blood samples (<50 µL). The proposed assays provide a promising method to enable point-of-care monitoring for timely personalized CBZ dosing.

18.
Biochem Pharmacol ; 177: 113995, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32339494

RESUMO

Few discoveries have influenced drug discovery programs more than the finding that mitochondrial membranes undergo swings in permeability in response to cellular perturbations. The conductor of these permeability changes is the aptly named mitochondrial permeability transition pore which, although not yet precisely defined, is comprised of several integral proteins that differentially act to regulate the flux of ions, proteins and metabolic byproducts during the course of cellular physiological functions but also pathophysiological insults. Pursuit of the pore's exact identity remains a topic of keen interest, but decades of research have unearthed provocative functions for the integral proteins leading to their evaluation to develop novel therapeutics for a wide range of clinical indications. Chief amongst these targeted, integral proteins have been the Voltage Dependent Anion Channel (VDAC) and the F1FO ATP synthase. Research associated with the roles and ligands of VDAC has been extensive and we will expand upon 3 examples of ligand:VDAC interactions for consideration of drug discovery projects: Tubulin:VDAC1, Hexokinase I/II:VDAC1 and olesoxime:VDAC1. The discoveries that cyclosporine blocks mitochondrial permeability transition via binding to cyclophilin D, and that cyclophilin D is an important component of F1FO ATP synthase, has heightened interest in the F1FO ATP synthase as a focal point for drug discovery, and we will discuss 2 plausible campaigns associated with disease indications. To date no drug has emerged from prospective targeting these integral proteins; however, continued exploration such as the approaches suggested in this Commentary will increase the likelihood of providing important therapeutics for severely unmet medical needs.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Colestenonas/uso terapêutico , Ciclosporina/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/genética , Canal de Ânion 1 Dependente de Voltagem/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Ciclofilinas/genética , Ciclofilinas/metabolismo , Regulação da Expressão Gênica , Hexoquinase/genética , Hexoquinase/metabolismo , Humanos , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , ATPases Mitocondriais Próton-Translocadoras/antagonistas & inibidores , ATPases Mitocondriais Próton-Translocadoras/genética , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/genética , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Permeabilidade/efeitos dos fármacos , Ligação Proteica , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Canal de Ânion 1 Dependente de Voltagem/antagonistas & inibidores , Canal de Ânion 1 Dependente de Voltagem/metabolismo
19.
J Neurosurg ; : 1-10, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731273

RESUMO

OBJECTIVE: The objective of this study was to determine patterns of care and outcomes in ruptured intracranial aneurysms (IAs) of the middle cerebral artery (MCA) in a contemporary national cohort. METHODS: The authors conducted a retrospective analysis of prospective data from a nationwide multicenter registry of all aneurysmal subarachnoid hemorrhage (aSAH) cases admitted to a tertiary care neurosurgical department in Switzerland in the years 2009-2015 (Swiss Study on Aneurysmal Subarachnoid Hemorrhage [Swiss SOS]). Patterns of care and outcomes at discharge and the 1-year follow-up in MCA aneurysm (MCAA) patients were analyzed and compared with those in a control group of patients with IAs in locations other than the MCA (non-MCAA patients). Independent predictors of a favorable outcome (modified Rankin Scale score ≤ 3) were identified, and their effect size was determined. RESULTS: Among 1866 consecutive aSAH patients, 413 (22.1%) harbored an MCAA. These MCAA patients presented with higher World Federation of Neurosurgical Societies grades (p = 0.007), showed a higher rate of concomitant intracerebral hemorrhage (ICH; 41.9% vs 16.7%, p < 0.001), and experienced delayed cerebral ischemia (DCI) more frequently (38.9% vs 29.4%, p = 0.001) than non-MCAA patients. After adjustment for confounders, patients with MCAA were as likely as non-MCAA patients to experience DCI (aOR 1.04, 95% CI 0.74-1.45, p = 0.830). Surgical treatment was the dominant treatment modality in MCAA patients and at a significantly higher rate than in non-MCAA patients (81.7% vs 36.7%, p < 0.001). An MCAA location was a strong independent predictor of surgical treatment (aOR 8.49, 95% CI 5.89-12.25, p < 0.001), despite statistical adjustment for variables traditionally associated with surgical treatment, such as (space-occupying) ICH (aOR 1.73, 95% CI 1.23-2.45, p = 0.002). Even though MCAA patients were less likely to die during the acute hospitalization (aOR 0.52, 0.30-0.91, p = 0.022), their rate of a favorable outcome was lower at discharge than that in non-MCAA patients (55.7% vs 63.7%, p = 0.003). At the 1-year follow-up, 68.5% and 69.6% of MCAA and non-MCAA patients, respectively, had a favorable outcome (p = 0.676). CONCLUSIONS: Microsurgical occlusion remains the predominant treatment choice for about 80% of ruptured MCAAs in a European industrialized country. Although patients with MCAAs presented with worse admission grades and greater rates of concomitant ICH, in-hospital mortality was lower and long-term disability was comparable to those in patients with non-MCAA.

20.
J Med Chem ; 50(5): 1050-7, 2007 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-17274609

RESUMO

The synthesis of a series of 3-beta-hydroxyethyl-4-arylquinolin-2-ones is described. These compounds contain hydrophilic and hydrophobic substituents ortho to the phenolic OH in the C ring of the quinolinone. Electrophysiological evaluation of the panel of compounds revealed that 11 and 16 with an unbranched ortho substituent retain activity as maxi-K ion channel openers. Members of this series of compounds can exist as stable atropisomers. Calculated estimates of the energy barrier for rotation around the aryl-aryl single bond in 3 is 31 kcal/mol. The atropisomers of (+/-)-3, (+/-)-4, and (+/-)-11 were separated by chiral HPLC and tested for their effect on maxi-K mediated outward current in hSlo injected X. laevis oocytes. The (-) isomer in each case was found to be more active than the corresponding (+) isomer, suggesting that the ion channel exhibits stereoselective activation. X-ray crystallographic structures of (+)-3 and (+)-11 were determined. Evaluation of the stability of (-)-3 at 80 degrees C in n-butanol indicated a 19.6% conversion to (+)-3 over 72 h. In human serum at 37 degrees C (-)-3 did not racemize over the course of the 30 h study.


Assuntos
Canais de Potássio Ativados por Cálcio de Condutância Alta/efeitos dos fármacos , Quinolinas/síntese química , Animais , Cristalografia por Raios X , Feminino , Humanos , Técnicas In Vitro , Ativação do Canal Iônico , Canais de Potássio Ativados por Cálcio de Condutância Alta/fisiologia , Estrutura Molecular , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Técnicas de Patch-Clamp , Quinolinas/química , Quinolinas/farmacologia , Estereoisomerismo , Termodinâmica , Xenopus laevis
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