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1.
Immunity ; 51(3): 491-507.e7, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533057

RESUMO

Tissue-resident memory CD8+ T (Trm) cells share core residency gene programs with tumor-infiltrating lymphocytes (TILs). However, the transcriptional, metabolic, and epigenetic regulation of Trm cell and TIL development and function is largely undefined. Here, we found that the transcription factor Bhlhe40 was specifically required for Trm cell and TIL development and polyfunctionality. Local PD-1 signaling inhibited TIL Bhlhe40 expression, and Bhlhe40 was critical for TIL reinvigoration following anti-PD-L1 blockade. Mechanistically, Bhlhe40 sustained Trm cell and TIL mitochondrial fitness and a functional epigenetic state. Building on these findings, we identified an epigenetic and metabolic regimen that promoted Trm cell and TIL gene signatures associated with tissue residency and polyfunctionality. This regimen empowered the anti-tumor activity of CD8+ T cells and possessed therapeutic potential even at an advanced tumor stage in mouse models. Our results provide mechanistic insights into the local regulation of Trm cell and TIL function.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proteínas de Homeodomínio/imunologia , Mitocôndrias/imunologia , Animais , Epigênese Genética/imunologia , Regulação da Expressão Gênica/imunologia , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptor de Morte Celular Programada 1/imunologia
3.
Nature ; 536(7617): 437-40, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27558064

RESUMO

At a distance of 1.295 parsecs, the red dwarf Proxima Centauri (α Centauri C, GL 551, HIP 70890 or simply Proxima) is the Sun's closest stellar neighbour and one of the best-studied low-mass stars. It has an effective temperature of only around 3,050 kelvin, a luminosity of 0.15 per cent of that of the Sun, a measured radius of 14 per cent of the radius of the Sun and a mass of about 12 per cent of the mass of the Sun. Although Proxima is considered a moderately active star, its rotation period is about 83 days (ref. 3) and its quiescent activity levels and X-ray luminosity are comparable to those of the Sun. Here we report observations that reveal the presence of a small planet with a minimum mass of about 1.3 Earth masses orbiting Proxima with a period of approximately 11.2 days at a semi-major-axis distance of around 0.05 astronomical units. Its equilibrium temperature is within the range where water could be liquid on its surface.


Assuntos
Planetas , Astros Celestes , Meio Ambiente Extraterreno/química , Rotação , Temperatura , Água/análise , Água/química
4.
Soft Matter ; 17(9): 2596-2602, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33523071

RESUMO

We report on measurements of self-diffusion coefficients in discrete numerical simulations of steady, homogeneous, collisional shearing flows of nearly identical, frictional, inelastic spheres. We focus on a range of relatively high solid volume fractions that are important in those terrestrial gravitational shearing flows that are dominated by collisional interactions. Diffusion over this range of solid fraction has not been well characterized in previous studies. We first compare the measured values with an empirical scaling based on shear rate previously proposed in the literature, and highlight the presence of anisotropy and the solid fraction dependence. We then compare the numerical measurements with those predicted by the kinetic theory for shearing flows of inelastic spheres and offer an explanation for why the measured and predicted values differ.

5.
Ecol Lett ; 23(4): 722-733, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32059265

RESUMO

The efficiency of carbon sequestration by the biological pump could decline in the coming decades because respiration tends to increase more with temperature than photosynthesis. Despite these differences in the short-term temperature sensitivities of photosynthesis and respiration, it remains unknown whether the long-term impacts of global warming on metabolic rates of phytoplankton can be modulated by evolutionary adaptation. We found that respiration was consistently more temperature dependent than photosynthesis across 18 diverse marine phytoplankton, resulting in universal declines in the rate of carbon fixation with short-term increases in temperature. Long-term experimental evolution under high temperature reversed the short-term stimulation of metabolic rates, resulting in increased rates of carbon fixation. Our findings suggest that thermal adaptation may therefore have an ameliorating impact on the efficiency of phytoplankton as primary mediators of the biological carbon pump.


Assuntos
Aquecimento Global , Fitoplâncton , Carbono , Ciclo do Carbono , Fotossíntese , Temperatura
6.
Catheter Cardiovasc Interv ; 95(4): 767-782, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726491

RESUMO

Endovascular repair of abdominal aortic aneurysms emerged initially as an alternative treatment strategy for patients considered to be inoperable or high risk for surgery. The evolution of endovascular techniques has made this technology a safe and less invasive alternative to open surgery for patients with suitable aortic anatomy. This manuscript reviews the current state of the art for endovascular AAA repair techniques, clinical outcomes, guideline recommendations, and future applications.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/mortalidade , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Humanos , Complicações Pós-Operatórias/etiologia , Desenho de Prótese , Medição de Risco , Fatores de Risco , Stents , Resultado do Tratamento
7.
BJU Int ; 125(4): 561-567, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31955483

RESUMO

OBJECTIVES: To externally validate a nomogram recently proposed by Larcher et al. (BJU Int. 2017; 120: 490) and to develop a simplified model with comparable accuracy to guide on the need for staging chest computed tomography (CT) for patients with new renal masses. PATIENTS AND METHODS: We analysed the data of 1082 consecutive patients with unilateral enhancing renal masses referred to urology multidisciplinary team meetings at two centres between 2011 and 2017. All patients underwent a staging chest CT at diagnosis. We fitted multivariable logistic regression models and tested the Larcher model performance using area under the receiver-operating curve (AUC), calibration and decision curve analysis. RESULTS: Forty-two patients (3.9%) had a positive chest CT. The Larcher nomogram had an AUC of 83.8% (95% confidence interval [CI] 77.1-90.6), but was only moderately well calibrated (calibration-in-the-large = -0.61, slope = 0.82). Specifically, the nomogram overestimated the risk of positive chest CT, and the magnitude of miscalibration increased with increasing predicted risks. Using a stepwise backward approach, a new model was developed including tumour size, nodal stage and systemic symptoms. Compared with the Larcher model, the new model had a similar AUC (82.7% [95% CI 75.5-90.0]), but improved calibration and clinical net benefit. The predicted risk of positive chest CT was <1% in the low-risk group and 1.9-79.9% in the high-risk group. CONCLUSION: The Larcher nomogram is an accurate prediction tool that was moderately well calibrated with our dataset. However, our simplified model has similar accuracy and uses more objective variables available from referral, so may be easier to incorporate into clinical practice. The low-risk group from our model (tumour size ≤4 cm and no systemic symptoms) had a risk of positive chest CT <1%, suggesting these patients may forego chest CT.


Assuntos
Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Nomogramas , Medição de Risco/métodos , Tomografia Computadorizada por Raios X , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Tórax/diagnóstico por imagem
8.
Phys Rev Lett ; 123(5): 058501, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31491296

RESUMO

We describe a new mechanism that produces bedforms and characterize the conditions under which it operates. The mechanism is associated with pressure gradients generated in a fluid saturated particle bed by a plate oscillating in the water above it. These vertical pressure gradients cause oscillatory bed failure. This facilitates particle displacement in its interior and transport at and near its surface that contribute to the formation of a heap under the plate. Flows over erodible beds generally cause shear stresses on the bed and these induce bed failure. Failure driven by pressure gradients is different from this. We report on bedforms in a bed of glass beads associated with such fluctuating pressure gradients. We measure the development of the profiles of heaps as a function of time and determine the tangential and normal motion of areas on the beds surface and estimate the depth of penetration of the tangential transport. The measurements compare favorably with a simple model that describes the onset of failure due to oscillations in pressure.

9.
Soft Matter ; 15(36): 7173-7178, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31490508

RESUMO

Geophysical flows that involve the transport of grains and the shearing of colloids and non-Brownian suspensions often take place above a substrate composed of the same particles that can be incorporated into the flow. Despite the importance of understanding such erodible beds to the phrasing of appropriate boundary conditions for the solution of continuum models, a rigorous definition of the erodible bed and the constitutive relations for the stresses within it are still lacking. Here, we use discrete-element simulations to show that the intense, intermittent forming and breaking of contact chains marks the transition to the erodible bed at a critical solid volume fraction, as in shear jamming of steady, homogeneous flows. However, the compressible, collisional flow that confines the bed is not strong enough to insure the stability of the contact network, resulting in a bulk stiffness that is three orders of magnitude less than in shear jamming.

10.
Gen Dent ; 67(5): 50-53, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31454323

RESUMO

A 14-year-old girl underwent extraction of an ankylosed primary left second molar as requested by her orthodontist. The developing mandibular left second premolar (tooth 20) was unintentionally removed during extraction of the primary molar. Immediate measures were taken to reimplant tooth 20. Recall appointments over the next 10 years included monitoring of tooth 20. The patient also was followed up closely by her orthodontist during this time. Tooth 20 was monitored for proper eruption, root development, and pulpal vitality. The tooth erupted normally, and the results of pulp testing continued to be within normal limits over the course of 10 years (with the exception of a single higher electric pulp test reading than that for adjacent teeth). Root formation was completed and appeared to be within normal limits. Pulpal calcification also occurred. At the most recent recall, the tooth remained asymptomatic. Monitoring will continue during the patient's regular recall appointments. The success of this case 10 years after reimplantation supports quick action to optimize the potential for long-term clinical success. The fact that tooth 20 was at a developmental stage also likely had a favorable impact on the outcome of this case.


Assuntos
Dente Molar , Erupção Dentária , Dente Decíduo , Adolescente , Dente Pré-Molar , Feminino , Seguimentos , Humanos , Tempo , Extração Dentária
11.
J Vasc Surg ; 66(4): 997-1006, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28390774

RESUMO

BACKGROUND: Fenestrated endovascular aneurysm repair (FEVAR) allows endovascular treatment of thoracoabdominal and juxtarenal aneurysms previously outside the indications of use for standard devices. However, because of considerable device costs and increased procedure time, FEVAR is thought to result in financial losses for medical centers and physicians. We hypothesized that surgeon leadership in the coding, billing, and contractual negotiations for FEVAR procedures will increase medical center contribution margin (CM) and physician reimbursement. METHODS: At the UMass Memorial Center for Complex Aortic Disease, a vascular surgeon with experience in medical finances is supported to manage the billing and coding of FEVAR procedures for medical center and physician reimbursement. A comprehensive financial analysis was performed for all FEVAR procedures (2011-2015), independent of insurance status, patient presentation, or type of device used. Medical center CM (actual reimbursement minus direct costs) was determined for each index FEVAR procedure and for all related subsequent procedures, inpatient or outpatient, 3 months before and 1 year subsequent to the index FEVAR procedure. Medical center CM for outpatient clinic visits, radiology examinations, vascular laboratory studies, and cardiology and pulmonary evaluations related to FEVAR were also determined. Surgeon reimbursement for index FEVAR procedure, related adjunct procedures, and assistant surgeon reimbursement were also calculated. All financial analyses were performed and adjudicated by the UMass Department of Finance. RESULTS: The index hospitalization for 63 FEVAR procedures incurred $2,776,726 of direct costs and generated $3,027,887 in reimbursement, resulting in a positive CM of $251,160. Subsequent related hospital procedures (n = 26) generated a CM of $144,473. Outpatient clinic visits, radiologic examinations, and vascular laboratory studies generated an additional CM of $96,888. Direct cost analysis revealed that grafts accounted for the largest proportion of costs (55%), followed by supplies (12%), bed (12%), and operating room (10%). Total medical center CM for all FEVAR services was $492,521. Average surgeon reimbursements per FEVAR from 2011 to 2015 increased from $1601 to $2480 while the surgeon payment denial rate declined from 50% to 0%. Surgeon-led negotiations with the Centers for Medicare & Medicaid Services during 2015 resulted in a 27% increase in physician reimbursement for the remainder of 2015 ($2480 vs $3068/case) and a 91% increase in reimbursement from 2011 ($1601 vs $3068). Assistant surgeon reimbursement also increased ($266 vs $764). Concomitant FEVAR-related procedures generated an additional $27,347 in surgeon reimbursement. CONCLUSIONS: Physician leadership in the coding, billing, and contractual negotiations for FEVAR results in a positive medical center CM and increased physician reimbursement.


Assuntos
Aneurisma Aórtico/economia , Aneurisma Aórtico/cirurgia , Implante de Prótese Vascular/economia , Codificação Clínica , Contratos/economia , Procedimentos Endovasculares/economia , Planos de Pagamento por Serviço Prestado/economia , Custos Hospitalares , Liderança , Negociação , Papel do Médico , Cirurgiões/economia , Atitude do Pessoal de Saúde , Benchmarking/economia , Implante de Prótese Vascular/classificação , Proposta de Concorrência/economia , Análise Custo-Benefício , Bases de Dados Factuais , Procedimentos Endovasculares/classificação , Planos de Pagamento por Serviço Prestado/classificação , Gastos em Saúde , Preços Hospitalares , Humanos , Massachusetts , Avaliação de Processos em Cuidados de Saúde/classificação , Avaliação de Processos em Cuidados de Saúde/economia , Estudos Retrospectivos , Resultado do Tratamento
12.
Biochem J ; 473(16): 2507-18, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27316461

RESUMO

The mammalian SPCA1 and SPCA2 ATPases localize in membranes of the secretory pathway and transport ions of Ca(2+) and Mn(2+) The role of tissue-specific SPCA2 isoform, highly expressed in lungs, mammary gland and gastrointestinal tract, is poorly understood. To elucidate the function of SPCA2, we studied human colon cancer HCT116 cells, grown under ambient and decreased O2 levels. We found that in contrast with other Ca(2+)-ATPase isoforms the expression of SPCA2 was up-regulated under hypoxia (3% O2), in both adherent (2D) and spheroid (3D) cultures. In spheroids, experiencing lowest O2 levels (30-50 µM, measured by phosphorescence lifetime imaging microscopy), we observed lower staining with reactive oxygen species (ROS)-specific fluorescent probe, which correlated with increased SPCA2. However, SPCA2 expression was up-regulated in cells exposed to reactive oxygen and nitrogen species donors, and when grown at higher density. We noticed that the culture exposed to hypoxia showed overall increase in S phase-positive cells and hypothesized that SPCA2 up-regulation under hypoxia can be linked to Mn(2+)-dependent cell cycle arrest. Consequently, we found that SPCA2-transfected cells display a higher number of cells entering S phase. Altogether, our results point at the important role of SPCA2 in regulation of cell cycle in cancer cells.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Cálcio/metabolismo , Neoplasias do Colo/metabolismo , Manganês/metabolismo , Oxigênio/metabolismo , Adesão Celular , Hipóxia Celular , Neoplasias do Colo/patologia , Citosol/metabolismo , Células HCT116 , Humanos , Transporte de Íons , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Esferoides Celulares
13.
Anal Chem ; 88(21): 10566-10572, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27696826

RESUMO

Live cells function within narrow limits of physiological temperature (T) and O2 and metabolite concentrations. We have designed a cell-permeable T-sensitive fluorescence lifetime-based nanoprobe based on lipophilic sulforhodamine, which stains 2D and 3D cell models, shows cytoplasmic localization, and has a robust response to T (∼0.037 ns/K). Subsequently, we evaluated the probe and fluorescence lifetime imaging microscopy (FLIM) technique for combined imaging of T and O2 gradients in metabolically active cells. We found that in adherent 2D culture of HCT116 cells intracellular T and O2 are close to ambient values. However, in 3D spheroid structures having size >200 µm, T and O2 gradients become pronounced. These microgradients can be enhanced by treatment with mitochondrial uncouplers or dissipated by drug-induced disaggregation of the spheroids. Thus, we demonstrate the existence of local microgradients of T in 3D cell models and utility of combined imaging of O2 and T.


Assuntos
Nanopartículas/química , Nanotecnologia , Rodaminas/química , Termômetros , Células HCT116 , Humanos , Microscopia de Fluorescência/métodos , Oxigênio/metabolismo , Esferoides Celulares/metabolismo , Temperatura
14.
J Interv Cardiol ; 28(3): 288-95, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25989717

RESUMO

BACKGROUND: Hemodialysis (HD) access failure is a common cause of increased morbidity and healthcare cost in patients with end stage renal disease (ESRD). Percutaneous balloon angioplasty has been used to treat hemodialysis access stenosis but is complicated by a high rate of restenosis. Percutaneous cutting balloon (PCB) angioplasty is an alternative approach that has shown to reduce restenosis. OBJECTIVES: The aim of the study is to assess the safety and efficacy of PCB angioplasty in comparison with conventional and high-pressure balloon angioplasty in the treatment of hemodialysis access site stenosis. METHODS: We searched PubMed, EMBASE and the Cochrane Central register of controlled trials (CENTRAL) databases through August 2014 and selected studies using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. We included all randomized clinical trials with a head-to-head comparison between PCB and conventional or high-pressure balloon angioplasty RESULTS: Three studies with 1034 participants (age 60.7 (±12.9) years and 50.1% males) with 525 in PCB and 509 in control arm were included in the analysis. The immediate procedural success rate was not significantly different in the PCB angioplasty and control arm respectively, (87.2% vs. 83.7% RD -0.02; 95%CI -0.06 to 0.01; P = 0.38). The six-month target lesion patency was significantly higher in the PCB angioplasty arm (67.2% vs. 55.6% RD 0.12; 95%CI 0.05-0.19; P < 0.05) with number needed to treat (NNT) of 9. The device related complications were not statistically significant between groups (RD 0.03; 95%CI -0.02 to 0.07; P = 0.26). CONCLUSIONS: PCB angioplasty is effective in treatment of hemodialysis access stenosis, with significantly higher six-month patency compared to balloon angioplasty.


Assuntos
Angioplastia com Balão/métodos , Derivação Arteriovenosa Cirúrgica , Constrição Patológica/terapia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal , Grau de Desobstrução Vascular
15.
Soft Matter ; 11(24): 4799-808, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-25976335

RESUMO

We extend models for granular flows based on the kinetic theory beyond the critical volume fraction at which a rate-independent contribution to the stresses develops. This involves the incorporation of a measure of the duration of the particle interaction before and after this volume fraction. At volume fractions less than the critical, the stress components contain contributions from momentum exchanged in collisions that are influenced by the particle elasticity. At volume fractions greater than the critical, the stress components contain both static contributions from particle elasticity and dynamic contributions from the momentum transfer associated with the release of elastic energy by the breaking of force chains. A simple expression for the duration of a collision before and after the critical volume fraction permits a smooth transition between the two regimes and predictions for the components of the stress in steady, homogeneous shearing that are in good agreement with the results of numerical simulations. Application of the theory to steady, inhomogeneous flows reproduces the features of such flows seen in numerical simulations and physical experiments.

16.
Bioorg Med Chem Lett ; 25(3): 581-6, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25556092

RESUMO

Through a ligand-based pharmacophore model (S)-proline based compounds were identified as potent cannabinoid receptor 2 (CB2) agonists with high selectivity over the cannabinoid receptor 1 (CB1). Structure-activity relationship investigations for this compound class lead to oxo-proline compounds 21 and 22 which combine an impressive CB1 selectivity profile with good pharmacokinetic properties. In a streptozotocin induced diabetic neuropathy model, 22 demonstrated a dose-dependent reversal of mechanical hyperalgesia.


Assuntos
Isoxazóis/química , Prolina/química , Ácido Pirrolidonocarboxílico/análogos & derivados , Receptor CB2 de Canabinoide/agonistas , Animais , Neuropatias Diabéticas/induzido quimicamente , Neuropatias Diabéticas/tratamento farmacológico , Meia-Vida , Humanos , Isoxazóis/farmacocinética , Isoxazóis/uso terapêutico , Ligantes , Masculino , Microssomos Hepáticos/metabolismo , Prolina/farmacocinética , Prolina/uso terapêutico , Ligação Proteica , Ácido Pirrolidonocarboxílico/química , Ácido Pirrolidonocarboxílico/farmacocinética , Ácido Pirrolidonocarboxílico/uso terapêutico , Ratos , Ratos Wistar , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Solubilidade , Relação Estrutura-Atividade
18.
Nanomedicine ; 9(3): 356-65, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22960192

RESUMO

Though gold nanoparticles have been considered bio-inert, recent studies have questioned their safety. To reduce the potential for toxicity, we developed a nanoclustering of gold and iron oxide as a nanoparticle (nanorose) which biodegrades into subunits to facilitate rapid excretion. In this present study, we demonstrate acid and macrophage lysosomal degradation of nanorose via loss of the near-infrared optical shift, and clearance of the nanorose in vivo following i.v. administration in C57BL/6 mice by showing gold concentration is significantly reduced in 11 murine tissues in as little as 31 days (P < 0.01). Hematology and chemistry show no toxicity of nanorose injected mice up to 14 days after administration. We conclude that the clustering design of nanorose does enhance the excretion of these nanoparticles, and that this could be a viable strategy to limit the potential toxicity of gold nanoparticles for clinical applications. FROM THE CLINICAL EDITOR: The potential toxicity of nanomaterials is a critically important limiting factor in their more widespread clinical application. Gold nanoparticles have been classically considered bio-inert, but recent studies have questioned their safety. The authors of this study have developed a clustering gold and iron oxide nanoparticle (nanorose), which biodegrades into subunits to facilitate rapid excretion, resulting in reduced toxicity.


Assuntos
Ouro/toxicidade , Ferro/toxicidade , Nanopartículas Metálicas/toxicidade , Testes de Toxicidade , Ácidos/química , Animais , Células Cultivadas , Ouro/administração & dosagem , Concentração de Íons de Hidrogênio , Injeções Intravenosas , Ferro/administração & dosagem , Luz , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Espalhamento de Radiação , Soluções , Espectrofotometria Ultravioleta , Fatores de Tempo
19.
Curr Cardiol Rev ; 19(1): e170322202296, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35301953

RESUMO

Patients with posterior circulation ischemia due to vertebral artery stenosis account for 20 to 25% of ischemic strokes and have an increased risk of recurrent stroke. In patients treated with medical therapy alone, the risk of recurrence is particularly increased in the first few weeks after symptoms occur, with an annual stroke rate of 10 to 15%. Additionally, obstructive disease of the vertebrobasilar system carries a worse prognosis, with a 30% mortality at 2-years if managed medically without additional surgical or endovascular intervention. Percutaneous transluminal angioplasty and stenting of symptomatic vertebral artery stenosis are promising options widely used in clinical practice with good technical results; however, the improved clinical outcome has been examined in various clinical trials without a sufficient sample size to conclusively determine whether stenting is better than medical therapy. Surgical revascularization is an alternative approach for the treatment of symptomatic vertebral artery stenosis that carries a 10-20% mortality rate. Despite the advances in medical therapy and endovascular and surgical options, symptomatic vertebral artery stenosis continues to impose a high risk of stroke recurrence with associated high morbidity and mortality. This review aims to provide a focused update on the percutaneous treatment of vertebral artery stenosis, its appropriate diagnostic approach, and advances in medical therapies.


Assuntos
Acidente Vascular Cerebral , Insuficiência Vertebrobasilar , Humanos , Artéria Vertebral/diagnóstico por imagem , Insuficiência Vertebrobasilar/diagnóstico , Insuficiência Vertebrobasilar/terapia , Insuficiência Vertebrobasilar/complicações , Angioplastia/efeitos adversos , Angioplastia/métodos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Resultado do Tratamento , Stents
20.
J Med Chem ; 66(2): 1583-1600, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36622903

RESUMO

Transient receptor potential ankyrin 1 (TRPA1) is a voltage-dependent, ligand-gated ion channel, and activation thereof is linked to a variety of painful conditions. Preclinical studies have demonstrated the role of TRPA1 receptors in a broad range of animal models of acute, inflammatory, and neuropathic pain. In addition, a clinical study using the TRPA1 antagonist GRC-17536 (Glenmark Pharmaceuticals) demonstrated efficacy in a subgroup of patients with painful diabetic neuropathy. Consequently, there is an increasing interest in TRPA1 inhibitors as potential analgesics. Herein, we report the identification of a fragment-like hit from a high-throughput screening (HTS) campaign and subsequent optimization to provide a novel and brain-penetrant TRPA1 inhibitor (compound 18, BAY-390), which is now being made available to the research community as an open-source in vivo probe.


Assuntos
Neuralgia , Canais de Potencial de Receptor Transitório , Animais , Analgésicos/farmacologia , Anquirinas , Canal de Cátion TRPA1
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