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1.
Lupus Sci Med ; 11(1)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38724182

RESUMO

OBJECTIVE: Explore organ-specific SLE burden by assessing health-related quality of life (HRQoL) and fatigue changes associated with Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) organ system response (score improvement) and belimumab treatment. METHODS: Data from four phase III belimumab trials were pooled for post hoc analysis (GSK Study 217382): BLISS-52 (NCT00424476), BLISS-76 (NCT00410384), BLISS-SC (NCT01484496) and EMBRACE (NCT01632241). Patients with baseline organ system involvement were classed as organ system responders if SELENA-SLEDAI scores for that organ system decreased at any post-baseline visit. HRQoL (36-Item Short Form Health Survey version 2 (SF-36v2)) and fatigue (Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue)) changes over 52 weeks were compared between organ system responders and non-responders, and separately between belimumab versus placebo treatment arms among organ system responders. Group-level differences were compared using analysis of variance; differences were interpreted using published group-level minimal important difference (MID). RESULTS: In these post hoc analyses, musculoskeletal and mucocutaneous organ system responders had greater SF-36v2 improvements than non-responders across most SF-36v2 domains, but differences were largely MID), with FACIT-Fatigue also improving >MID for renal responders receiving belimumab. CONCLUSIONS: SLE disease burden differs with the organ system(s) involved. While these analyses are limited by mutual inclusivity of organ system groupings, differing patient numbers between groups and small numbers in some groups, they suggest that mucocutaneous and musculoskeletal organ system response improves SF-36v2 domain scores; cardiovascular and respiratory organ system response may meaningfully improve fatigue; and belimumab may offer additional HRQoL or fatigue benefits beyond standard therapy for musculoskeletal and renal responders.


Assuntos
Anticorpos Monoclonais Humanizados , Fadiga , Lúpus Eritematoso Sistêmico , Qualidade de Vida , Índice de Gravidade de Doença , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/complicações , Fadiga/tratamento farmacológico , Fadiga/etiologia , Feminino , Adulto , Masculino , Pessoa de Meia-Idade , Imunossupressores/uso terapêutico , Resultado do Tratamento , Ensaios Clínicos Fase III como Assunto
2.
bioRxiv ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38405985

RESUMO

A central problem in cancer immunotherapy with immune checkpoint blockade (ICB) is the development of resistance, which affects 50% of patients with metastatic melanoma1,2. T cell exhaustion, resulting from chronic antigen exposure in the tumour microenvironment, is a major driver of ICB resistance3. Here, we show that CD38, an ecto-enzyme involved in nicotinamide adenine dinucleotide (NAD+) catabolism, is highly expressed in exhausted CD8+ T cells in melanoma and is associated with ICB resistance. Tumour-derived CD38hiCD8+ T cells are dysfunctional, characterised by impaired proliferative capacity, effector function, and dysregulated mitochondrial bioenergetics. Genetic and pharmacological blockade of CD38 in murine and patient-derived organotypic tumour models (MDOTS/PDOTS) enhanced tumour immunity and overcame ICB resistance. Mechanistically, disrupting CD38 activity in T cells restored cellular NAD+ pools, improved mitochondrial function, increased proliferation, augmented effector function, and restored ICB sensitivity. Taken together, these data demonstrate a role for the CD38-NAD+ axis in promoting T cell exhaustion and ICB resistance, and establish the efficacy of CD38 directed therapeutic strategies to overcome ICB resistance using clinically relevant, patient-derived 3D tumour models.

3.
Soft Matter ; 20(2): 351-364, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38093637

RESUMO

Electric double layers are crucial to energy storage and electrocatalytic device performance. While double layer formation originates in electrostatic interactions, electric double layer properties are governed by a balance of both electrostatic and entropic driving forces. Favorable ion-surface electrostatic interactions attract counterions to charged surfaces to compensate, or "screen," potentials, but the confinement of these same ions from a bulk reservoir to the interface incurs an entropic penalty. Here, we use a dicationic imidazolium ionic liquid and its monovalent analogue to explore how cation valence and entropy influence double layer formation and electrochemical reactivity using CO2 electroreduction as a model reaction. We find that divalent and monovalent cations display similar CO2 reduction kinetics but differ vastly in steady-state reactivity due to rapid electrochemically induced precipitation of insulating dicationic (bi)carbonate films. Using in situ surface-enhanced Raman scattering spectroscopy, we find that potential-dependent cation reorientation occurs at similar potentials between the two ionic liquids, but the introduction of a covalent link in the divalent cation imparts a more ordered double layer structure that favors (bi)carbonate precipitation. In mixed monovalent-divalent electrolytes, we find that the divalent cations dominate interfacial properties by preferentially accumulating at surfaces even at very low relative concentrations. Our findings confirm that ion entropy plays a key role in modulating local electrochemical environments. Furthermore, we highlight how double layer properties are sensitive to the properties of counterions that pay the lowest entropic penalty to accumulate at interfaces. Overall, we illustrate that ion entropy provides a new knob to tune reaction microenvironments and unveil how entropy plays a major role in modulating electrochemical reactivity in mixed ion electrolytes.

4.
Nature ; 615(7950): 158-167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36634707

RESUMO

Despite the success of PD-1 blockade in melanoma and other cancers, effective treatment strategies to overcome resistance to cancer immunotherapy are lacking1,2. Here we identify the innate immune kinase TANK-binding kinase 1 (TBK1)3 as a candidate immune-evasion gene in a pooled genetic screen4. Using a suite of genetic and pharmacological tools across multiple experimental model systems, we confirm a role for TBK1 as an immune-evasion gene. Targeting TBK1 enhances responses to PD-1 blockade by decreasing the cytotoxicity threshold to effector cytokines (TNF and IFNγ). TBK1 inhibition in combination with PD-1 blockade also demonstrated efficacy using patient-derived tumour models, with concordant findings in matched patient-derived organotypic tumour spheroids and matched patient-derived organoids. Tumour cells lacking TBK1 are primed to undergo RIPK- and caspase-dependent cell death in response to TNF and IFNγ in a JAK-STAT-dependent manner. Taken together, our results demonstrate that targeting TBK1 is an effective strategy to overcome resistance to cancer immunotherapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Evasão da Resposta Imune , Imunoterapia , Proteínas Serina-Treonina Quinases , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunoterapia/métodos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Organoides , Fatores de Necrose Tumoral/imunologia , Interferon gama/imunologia , Esferoides Celulares , Caspases , Janus Quinases , Fatores de Transcrição STAT
5.
Adv Ther ; 38(7): 3948-3961, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34091866

RESUMO

INTRODUCTION: There are limited real-world data on treatment patterns, comorbidities, and healthcare burden in pediatric patients with psoriasis. We examined patient demographics, comorbidity burden, treatment patterns, and healthcare use and costs in pediatric psoriasis. METHODS: A retrospective, real-world, exploratory study was conducted using US claims databases. Pediatric patients aged < 18 years with newly diagnosed psoriasis (index date) were selected from IBM® MarketScan® databases (2016-2018). Patients were enrolled continuously for ≥ 12 months pre- and post-index date. Pre-index demographics, comorbidity, treatment drug classes prescribed, and post-index healthcare resource utilization and costs were studied. Study measures are reported for total population and by severity (categorized as mild and moderate-to-severe psoriasis). Variables were compared using t-test (continuous) or chi-square and Fisher's exact test (categorical). RESULTS: Overall, 4754 pediatric patients with psoriasis (58.3% females) met the selection criteria and were included in the study. Mean and standard deviation (SD) age was 12.6 (3.7) years on index date, with 13.4% patients having moderate-to-severe psoriasis. The mean (SD) Deyo-Charlson Comorbidity Index was 0.14 (0.40); anxiety (6.6%), depression (4.1%), and obesity (3.9%) were the most prevalent comorbidities observed. Topical treatments were prescribed to most patients as first-line treatment of mild (79.1%) and moderate-to-severe (52.0%) psoriasis. Other first-line therapies prescribed in moderate-to-severe cases included non-biologic systemics (21.0%), phototherapy (15.0%), and biologics (9.2%). Healthcare use and costs increased with psoriasis severity during the post-index period. Mean annual total all-cause costs per patient were higher for patients with moderate-to-severe psoriasis compared with mild psoriasis ($27,541 vs. $5,034; P < 0.001). CONCLUSIONS: Psychiatric, metabolic, and inflammatory disorders were observed comorbidities in pediatric patients with psoriasis. For moderate-to-severe psoriasis, topicals, phototherapy, and biologics were a common first-, second-, and third-line treatment sequence. Higher unadjusted healthcare costs by severity were driven by outpatient prescription costs.


Assuntos
Revisão da Utilização de Seguros , Psoríase , Criança , Comorbidade , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Psoríase/tratamento farmacológico , Psoríase/epidemiologia , Estudos Retrospectivos
6.
Rheumatol Ther ; 8(1): 599-607, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484433

RESUMO

INTRODUCTION: This study describes the frequency of prescription claims for drugs that may interact with Janus kinase (JAK) inhibitors among adult patients with rheumatoid arthritis (RA) in a large US claims database. METHODS: This observational, retrospective, cross-sectional study of the IBM® MarketScan® Research Commercial and the Medicare Supplemental Database included adults (≥ 18 years) with ≥ 2 outpatient claims 30 or more days apart or ≥ 1 inpatient visit claim with an RA diagnosis between January 1, 2013 and March 31, 2017 (the index period). During the study period, from January 1, 2013 to March 31, 2018, strong organic anion transporter (OAT3) inhibitors, strong cytochrome P450 (CYP) 3A4 inhibitors, and moderate or strong CYP3A4 inhibitors in combination with strong CYP2C19 inhibitors, were identified as drugs with potential for drug-drug interactions (DDIs) with JAK inhibitors approved for RA treatment in the US. Descriptive statistics were conducted. RESULTS: A total of 152,853 patients met eligibility criteria. Approximately 76% were women and the median age was 57 years. Of these patients, < 0.1% had a claim for a strong OAT3 inhibitor, and 1% had claims for the combination of a strong CYP3A4 and strong CYP2C19 inhibitor; 3% of patients had a claim for a strong CYP3A4 inhibitor and almost 10% had claims for both a moderate CYP3A4 and a strong CYP2C19 inhibitor. CONCLUSIONS: Up to 10% of RA patients have been prescribed a drug with a potential JAK interaction. Rheumatologists should consider potential DDIs when managing patients with RA.

7.
J Clin Lipidol ; 14(6): 791-798, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33011136

RESUMO

BACKGROUND: Adherence to statin medications is suboptimal; however, the association of statin adherence, as defined in medication adherence quality measures, with healthcare service use and expenditure within one year has not been assessed in a commercially insured United States (US) population. OBJECTIVE: To investigate the relationship between statin adherence, as specified in the Pharmacy Quality Alliance (PQA) statin medication adherence quality measure, and healthcare resource utilization and expenditures within commercial health plans over a one-year period. METHODS: This one-year retrospective analysis involved a cohort of individuals from the Truven Health MarketScan Commercial Claims and Encounters Research Databases (2009-2015). Generalized linear models with log link and negative binomial distribution (use) or gamma distribution (expenditures) were used to assess relationships between medication adherence (≥80% proportion of days covered) and healthcare use and expenditures (adjusted to 2015 US dollars) while adjusting for covariates. Beta coefficients were used to compute cost ratios (CR) and rate ratios (RR). An alpha level of 0.001 was set a priori. RESULTS: Of 4,450,308 eligible individuals, 2,757,288 (61.9%) were classified as adherent. Multivariable analyses indicated adherent individuals had more outpatient (RR = 1.009, 95% CI = 1.007, 1.010) and fewer inpatient visits (RR = 0.756, 95% CI = 0.749, 0.762); and lower outpatient (CR = 0.965, 95% CI = 0.963, 0.967), inpatient (CR = 0.780, 95% CI = 0.779, 0.782), and total expenditures (CR = 0.975, 95% CI = 0.973, 0.977). Adherence was associated with lower per member per month total healthcare expenditures ($18.91) vs nonadherence. CONCLUSION: Within one year, statin adherence was associated with more outpatient and fewer inpatient visits, lower outpatient and inpatient expenditures, and lower total expenditures than nonadherence, within a commercially-insured population.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Seguro Saúde/estatística & dados numéricos , Adesão à Medicação/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Hospitalização , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/economia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Am J Emerg Med ; 38(9): 1802-1806, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32739851

RESUMO

OBJECTIVES: The objective of this study was to compare emergency department (ED) length of stay (LOS) between patients treated with opioid analgesia versus non-opioid analgesia for low back pain (LBP) in the ED. METHODS: We conducted a secondary analysis of National Hospital Ambulatory Medical Care Survey (NHAMCS) data (2014-2015). Adults (age ≥18 years) who presented to the ED with a reason for visit or primary diagnosis of LBP were included in the final study sample. Patient visits were categorized into two groups based on whether they received opioid analgesia (with or without non-opioid analgesia) or non-opioid analgesia only in the ED. The primary outcome measure was ED LOS, which was log-transformed (as ED LOS was not normally distributed) for analysis. A multivariable linear regression analysis was used to evaluate the association between opioid use and ED LOS. RESULTS: The study sample consisted of a national estimate of approximately 8.6 million ED visits for LBP (during 2014-2015), of which 60.1% received opioids and 39.9% received non-opioids only. The geometric mean ED LOS for patient visits who received opioids was longer than patient visits who received non-opioids (142 versus 92 min, respectively; p < 0.001). After adjusting for confounders in the multivariable analysis, patient visits that received opioids had a significantly longer ED LOS (coefficient 0.25; 95% CI 0.11 to 0.38; p < 0.001). CONCLUSIONS: In a nationally representative sample of patient visits to ED due to LBP in the US, use of opioids in the ED was associated with an increased ED LOS.


Assuntos
Analgésicos Opioides/uso terapêutico , Serviço Hospitalar de Emergência/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Dor Lombar/tratamento farmacológico , Padrões de Prática Médica/estatística & dados numéricos , Adulto , Analgésicos/uso terapêutico , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Medição da Dor , Estados Unidos
9.
Cell Rep ; 30(6): 2028-2039.e4, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32049029

RESUMO

The vagus nerve conveys gastrointestinal cues to the brain to control eating behavior. In obesity, vagally mediated gut-brain signaling is disrupted. Here, we show that the cocaine- and amphetamine-regulated transcript (CART) is a neuropeptide synthesized proportional to the food consumed in vagal afferent neurons (VANs) of chow-fed rats. CART injection into the nucleus tractus solitarii (NTS), the site of vagal afferent central termination, reduces food intake. Conversely, blocking endogenous CART action in the NTS increases food intake in chow-fed rats, and this requires intact VANs. Viral-mediated Cartpt knockdown in VANs increases weight gain and daily food intake via larger meals and faster ingestion rate. In obese rats fed a high-fat, high-sugar diet, meal-induced CART synthesis in VANs is blunted and CART antibody fails to increase food intake. However, CART injection into the NTS retains its anorexigenic effect in obese rats. Restoring disrupted VAN CART signaling in obesity could be a promising therapeutic approach.


Assuntos
Hiperfagia/genética , Proteínas do Tecido Nervoso/metabolismo , Nervo Vago/efeitos dos fármacos , Aumento de Peso/genética , Animais , Humanos , Masculino , Ratos
10.
J Ind Microbiol Biotechnol ; 45(9): 795-801, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29915996

RESUMO

Livestock and fish farming are rapidly growing industries facing the simultaneous pressure of increasing production demands and limited protein required to produce feed. Bacteria that can convert low-value non-food waste streams into singe cell protein (SCP) present an intriguing route for rapid protein production. The oleaginous bacterium Rhodococcus opacus serves as a model organism for understanding microbial lipid production. SCP production has not been explored using an organism from this genus. In the present research, R. opacus strains DSM 1069 and PD630 were fed three agro-waste streams: (1) orange pulp, juice, and peel; (2) lemon pulp, juice, and peel; and (3) corn stover effluent, to determine if these low-cost substrates would be suitable for producing a value-added product, SCP for aquafarming or livestock feed. Both strains used agro-waste carbon sources as a growth substrate to produce protein-rich cell biomass suggesting that that R. opacus can be used to produce SCP using agro-wastes as low-cost substrates.


Assuntos
Proteínas Alimentares/metabolismo , Rhodococcus/metabolismo , Biomassa , Produtos Agrícolas/química , Fermentação
11.
AMB Express ; 7(1): 185, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-28963644

RESUMO

Use of oleaginous microorganisms as "micro-factories" for accumulation of single cell oils for biofuel production has increased significantly to mitigate growing energy demands, resulting in efforts to upgrade industrial waste, such as second-generation lignocellulosic residues, into potential feedstocks. Dilute-acid pretreatment (DAP) is commonly used to alter the physicochemical properties of lignocellulosic materials and is typically coupled with simultaneous saccharification and fermentation (SSF) for conversion of sugars into ethanol. The resulting DAP residues are usually processed as a waste stream, e.g. burned for power, but this provides minimal value. Alternatively, these wastes can be utilized as feedstock to generate lipids, which can be converted to biofuel. DAP-SSF residues were generated from pine, poplar, and switchgrass. High performance liquid chromatography revealed less than 0.13% monomeric sugars in the dry residue. Fourier transform infrared spectroscopy was indicative of the presence of lignin and polysaccharides. Gel permeation chromatography suggested the bacterial strains preferred molecules with molecular weight ~ 400-500 g/mol. DAP-SSF residues were used as the sole carbon source for lipid production by Rhodococcus opacus DSM 1069 and PD630 in batch fermentations. Depending on the strain of Rhodococcus employed, 9-11 lipids for PD630 and DSM 1069 were observed, at a final concentration of ~ 15 mg/L fatty acid methyl esters (FAME) detected. Though the DAP-SSF substrate resulted in low FAME titers, novel analysis of solid-state fermentations was investigated, which determined that DAP-SSF residues could be a viable feedstock for lipid generation.

12.
Am J Physiol Gastrointest Liver Physiol ; 313(4): G342-G352, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28705805

RESUMO

There is a lack of tools that selectively target vagal afferent neurons (VAN) innervating the gut. We use saporin (SAP), a potent neurotoxin, conjugated to the gastronintestinal (GI) hormone cholecystokinin (CCK-SAP) injected into the nodose ganglia (NG) of male Wistar rats to specifically ablate GI-VAN. We report that CCK-SAP ablates a subpopulation of VAN in culture. In vivo, CCK-SAP injection into the NG reduces VAN innervating the mucosal and muscular layers of the stomach and small intestine but not the colon, while leaving vagal efferent neurons intact. CCK-SAP abolishes feeding-induced c-Fos in the NTS, as well as satiation by CCK or glucagon like peptide-1 (GLP-1). CCK-SAP in the NG of mice also abolishes CCK-induced satiation. Therefore, we provide multiple lines of evidence that injection of CCK-SAP in NG is a novel selective vagal deafferentation technique of the upper GI tract that works in multiple vertebrate models. This method provides improved tissue specificity and superior separation of afferent and efferent signaling compared with vagotomy, capsaicin, and subdiaphragmatic deafferentation.NEW & NOTEWORTHY We develop a new method that allows targeted lesioning of vagal afferent neurons that innervate the upper GI tract while sparing vagal efferent neurons. This reliable approach provides superior tissue specificity and selectivity for vagal afferent over efferent targeting than traditional approaches. It can be used to address questions about the role of gut to brain signaling in physiological and pathophysiological conditions.


Assuntos
Vias Aferentes/efeitos dos fármacos , Denervação Autônoma/métodos , Trato Gastrointestinal/efeitos dos fármacos , Bloqueio Nervoso/métodos , Proteínas Inativadoras de Ribossomos Tipo 1/administração & dosagem , Nervo Vago/efeitos dos fármacos , Vias Aferentes/fisiologia , Animais , Trato Gastrointestinal/fisiologia , Masculino , Neurotoxinas/administração & dosagem , Neurotoxinas/farmacologia , Ratos , Ratos Wistar , Saporinas , Resultado do Tratamento , Nervo Vago/fisiologia
13.
Channels (Austin) ; 7(4): 322-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23807090

RESUMO

Large conductance calcium-activated potassium (BK) channels are widely expressed in the nervous system. We have recently shown that principal neurons from canine intracardiac ganglia (ICG) express a paxilline- and TEA-sensitive BK current, which increases neuronal excitability. In the present work, we further explore the molecular constituents of the BK current in canine ICG. We found that the ß1 and ß4 regulatory subunits are expressed in ICG. Single channel voltage-dependence at different calcium concentrations suggested that association of the BKα with a particular ß subunit was not enough to explain the channel activity in this tissue. Indeed, we detected the presence of several splice variants of the BKα subunit. In conclusion, BK channels in canine ICG may result from the arrangement of different BKα splice variants, plus accessory ß subunits. The particular combinations expressed in canine IC neurons likely rule the excitatory role of BK current in this tissue.


Assuntos
Gânglios/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Miocárdio/citologia , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Cães , Canais de Potássio Ativados por Cálcio de Condutância Alta/química , Dados de Sequência Molecular , Neurônios/metabolismo , Subunidades Proteicas/química , Subunidades Proteicas/metabolismo
14.
Am J Physiol Cell Physiol ; 304(3): C280-6, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23195072

RESUMO

We studied principal neurons from canine intracardiac (IC) ganglia to determine whether large-conductance calcium-activated potassium (BK) channels play a role in their excitability. We performed whole cell recordings in voltage- and current-clamp modes to measure ion currents and changes in membrane potential from isolated canine IC neurons. Whole cell currents from these neurons showed fast- and slow-activated outward components. Both current components decreased in the absence of calcium and following 1-2 mM tetraethylammonium (TEA) or paxilline. These results suggest that BK channels underlie these current components. Single-channel analysis showed that BK channels from IC neurons do not inactivate in a time-dependent manner, suggesting that the dynamic of the decay of the fast current component is akin to that of intracellular calcium. Immunohistochemical studies showed that BK channels and type 2 ryanodine receptors are coexpressed in IC principal neurons. We tested whether BK current activation in these neurons occurred via a calcium-induced calcium release mechanism. We found that the outward currents of these neurons were not affected by the calcium depletion of intracellular stores with 10 mM caffeine and 10 µM cyclopiazonic acid. Thus, in canine intracardiac neurons, BK currents are directly activated by calcium influx. Membrane potential changes elicited by long (400 ms) current injections showed a tonic firing response that was decreased by TEA or paxilline. These data strongly suggest that the BK current present in canine intracardiac neurons regulates action potential activity and could increase these neurons excitability.


Assuntos
Coração/fisiologia , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Neurônios/metabolismo , Neurônios/fisiologia , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Cálcio/metabolismo , Cães , Gânglios/efeitos dos fármacos , Gânglios/metabolismo , Gânglios/fisiologia , Coração/efeitos dos fármacos , Indóis/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp/métodos , Potássio/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , Tetraetilamônio/farmacologia
15.
Pediatr Radiol ; 42(7): 878-80, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21984317

RESUMO

We describe a case of extraosseous chordoma disseminated in the subarachnoid space with favorable long-term follow-up. During work-up of headaches in a 13-year-old girl, MRI revealed multiple cystic subarachnoid masses in the posterior fossa and spinal canal. She underwent posterior fossa craniectomy and was found to have multicentric subarachnoid chordomas with positive CSF cytology. Six years after the operation and radiotherapy, the girl is without neurological deficits despite persistent multiple subarachnoid cystic masses.


Assuntos
Cordoma/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/patologia , Adolescente , Feminino , Humanos , Prognóstico
17.
Yeast ; 23(11): 795-802, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16921553

RESUMO

The Candida albicans CDR1 gene, encoding an ABC transporter that functions as an efflux pump, is thought to be involved in pathogenic adaptation and uses mammalian hormones and other environmental cues to regulate its activity. Exposure of several clinical isolates of C. albicans to 1 x 10(-8) M 17beta-oestradiol increased CDR1 expression and the isolates showed a positive correlation between oestrogen induction of CDR1 and growth in the presence of oestrogen. A reporter strain carrying the GFP gene under the control of the CDR1 promoter was used to analyse the effect of steroid hormones and antifungal drugs on CDR1 expression by flow cytometry. We found that among the many hormones tested, only oestradiol and progesterone induce CDR1 expression. CDR1 induction requires hormone concentrations greater than 10(-8) M, a threshold reached in vivo only by progesterone. Using the GFP-reporter strain, we show CDR1 induction by female but not male human serum and demonstrate that exposure of C. albicans to physiological concentrations of progesterone measurably increases resistance to fluconazole, miconazole and 5-fluorouracil. Simultaneous exposure of C. albicans to hormones and antifungal drugs provided evidence that both agents induce CDR1 expression via different mechanisms with different saturation points.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Candida albicans/metabolismo , Estradiol/farmacologia , Proteínas Fúngicas/biossíntese , Proteínas de Membrana Transportadoras/biossíntese , Progesterona/farmacologia , Candida albicans/genética , Candida albicans/isolamento & purificação , Farmacorresistência Fúngica , Feminino , Citometria de Fluxo/métodos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Masculino , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo
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