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1.
J Comput Chem ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007399

RESUMO

Metal halide perovskites are crystalline materials with a sharp increase in popularity and rapidly becoming a major contender for optoelectronic device applications. In this work, we provide the optoelectronic features of a possible novel candidate, ZSnCl3 (Z = Na/K) Sn-based on a detailed numerical simulation. The output of the current computations is compared to the results that are currently available, and a respectable agreement is noted. The studied compounds were cubic in nature and structurally stabe. The mechanical properties reflect the mechanical stability and ductility of the proposed materials. The Sn-based single perovskite compounds proposed in this study are mechanically stable and ductile. The narrow direct band gap for NaSnCl3 and KSnCl3 are 1.36 eV and 1.47 eV, respectively, using the HSE06 hybrid function with the Boltztrp2 integrated in Quantum ESPRESSO (QE) software. The effective use of these compounds in perovskite solar cells and other optoelectronic applications was confirmed by optical absorption spectral measurements conducted in the photon energy range of 0-20 eV.

2.
Cell ; 137(7): 1308-19, 2009 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-19563761

RESUMO

Post-Golgi vesicles target and deliver most biosynthetic cargoes to the cell surface. However, the molecules and mechanisms involved in fusion of these vesicles are not well understood. We have employed a system to simultaneously monitor release of luminal and membrane biosynthetic cargoes from individual post-Golgi vesicles. Exocytosis of these vesicles is not calcium triggered. Release of luminal cargo can be accompanied by complete, partial, or no release of membrane cargo. Partial and no release of membrane cargo of a fusing vesicle are fates associated with kiss-and-run exocytosis, and we find that these are the predominant mode of post-Golgi vesicle exocytosis. Partial cargo release by post-Golgi vesicles occurs because of premature closure of the fusion pore and is modulated by the activity of clathrin, actin, and dynamin. Our results demonstrate that these components of the endocytic machinery modulate the nature and extent of biosynthetic cargo delivery by post-Golgi vesicles at the cell membrane.


Assuntos
Exocitose , Vesículas Transportadoras/metabolismo , Actinas/metabolismo , Membrana Celular/metabolismo , Clatrina/metabolismo , Dinaminas/metabolismo , Complexo de Golgi/metabolismo , Humanos , Microscopia de Fluorescência , Mutação , Proteína 1A de Ligação a Tacrolimo/genética
3.
Microbiology (Reading) ; 169(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36748569

RESUMO

We previously showed that specific polyamines (PAs) present in the extracellular environment markedly affect extracellular polysaccharide (EPS) production, biofilm formation and motility in Sinorhizobium meliloti Rm8530. We hypothesized that extracellular PA signals were sensed and transduced by the NspS and MbaA proteins, respectively, which are homologs of the PA-sensing, c-di-GMP modulating NspS-MbaA proteins described in Vibrio cholerae. Here we show that the decrease in biofilm formation and EPS production in the quorum-sensing (QS)-deficient S. meliloti wild-type strain 1021 in cultures containing putrescine or spermine did not occur in a 1021 nspS mutant (1021 nspS). The transcriptional expression of nspS in strain 1021 was significantly increased in cultures containing either of these polyamines, but not by exogenous cadaverine, 1,3-diaminopropane (DAP), spermidine (Spd) or norspermidine (NSpd). Cell aggregation in liquid cultures did not differ markedly between strain 1021 and 1021 nspS in the presence or absence of PAs. The S. meliloti QS-proficient Rm8530 wild-type and nspS mutant (Rm8530 nspS) produced similar levels of biofilm under control conditions and 3.2- and 2.2-fold more biofilm, respectively, in cultures with NSpd, but these changes did not correlate with EPS production. Cells of Rm8530 nspS aggregated from two- to several-fold more than the wild-type in cultures without PAs or in those containing Spm. NSpd, Spd and DAP differently affected swimming and swarming motility in strains 1021 and Rm8530 and their respective nspS mutants. nspS transcription in strain Rm8530 was greatly reduced by exogenous Spm. Bioinformatic analysis revealed similar secondary structures and functional domains in the MbaA proteins of S. meliloti and V. cholerae, while their NspS proteins differed in some residues implicated in polyamine recognition in the latter species. NspS-MbaA homologs occur in a small subset of soil and aquatic bacterial species that commonly interact with eukaryotes. We speculate that the S. meliloti NspS-MbaA system modulates biofilm formation, EPS production and motility in response to environmental or host plant-produced PAs.


Assuntos
Poliaminas , Sinorhizobium meliloti , Poliaminas/metabolismo , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes , Regulação Bacteriana da Expressão Gênica , Polissacarídeos Bacterianos/metabolismo
4.
Virol J ; 20(1): 207, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679779

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection induces a spectrum of clinical manifestations that depend on the immune response of the patient, i.e., from an asymptomatic form to an inflammatory response with multiorgan deterioration. In some cases, severe cases of SARS-CoV-2 are characterized by an excessive, persistent release of inflammatory mediators known as a cytokine storm. This phenomenon arises from an ineffective T helper (Th)-1 response, which is unable to control the infection and leads to a reinforcement of innate immunity, causing tissue damage. The evolution of the disease produced by SARS-CoV2, known as COVID-19, has been of interest in several research fields. Asthma patients have been reported to present highly variable outcomes due to the heterogeneity of the disease. For example, the Th2 response in patients with allergic asthma is capable of decreasing Th1 activation in COVID-19, preventing the onset of a cytokine storm; additionally, IL-33 released by damaged epithelium in the context of COVID-19 potentiates either Th1 or T2-high responses, a process that contributes to poor outcomes. IL-13, a T2-high inflammatory cytokine, decreases the expression of angiotensin converting enzyme-2 (ACE2) receptor, hindering SARS-CoV-2 entry; finally, poor outcomes have been observed in COVID-19 patients with severe neutrophilic asthma. In other contexts, the COVID-19 lockdown has had interesting effects on asthma epidemiology. The incidence of asthma in the most populated states in Mexico, including Tamaulipas, which has the highest asthma incidence in the country, showed similar tendencies independent of how strict the lockdown measures were in each state. As described worldwide for various diseases, a decrease in asthma cases was observed during the COVID-19 lockdown. This decrease was associated with a drop in acute respiratory infection cases. The drop in cases of various diseases, such as diabetes, hypertension or depression, observed in 2020 was restored in 2022, but not for asthma and acute respiratory infections. There were slight increases in asthma cases when in-person classes resumed. In conclusion, although many factors were involved in asthma outcomes during the pandemic, it seems that acute respiratory infection is intimately linked to asthma cases. Social distancing during remote learning, particularly school lockdown, appears to be an important cause of the decrease in cases.


Assuntos
Asma , COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Síndrome da Liberação de Citocina/epidemiologia , RNA Viral , Controle de Doenças Transmissíveis , Asma/epidemiologia
5.
Bioorg Med Chem Lett ; 80: 129084, 2023 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-36423823

RESUMO

In the treatment of non-small cell lung cancer (NSCLC), patients harboring exon 20 insertion mutations in the epidermal growth factor receptor (EGFR) gene (EGFR) have few effective therapies because this subset of mutants is generally resistant to most currently approved EGFR inhibitors. This report describes the structure-guided design of a novel series of potent, irreversible inhibitors of EGFR exon 20 insertion mutations, including the V769_D770insASV and D770_N771insSVD mutants. Extensive structure-activity relationship (SAR) studies led to the discovery of mobocertinib (compound 21c), which inhibited growth of Ba/F3 cells expressing the ASV insertion with a half-maximal inhibitory concentration of 11 nM and with selectivity over wild-type EGFR. Daily oral administration of mobocertinib induced tumor regression in a Ba/F3 ASV xenograft mouse model at well-tolerated doses. Mobocertinib was approved in September 2021 for the treatment of adult patients with advanced NSCLC with EGFR exon 20 insertion mutations with progression on or after platinum-based chemotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Camundongos , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutagênese Insercional , Mutação , Receptores ErbB , Éxons , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
6.
Acta Neurochir (Wien) ; 165(12): 4183-4189, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37831227

RESUMO

PURPOSE: The population is aging, and age remains an important factor in deciding surgical candidacy for intracranial tumors. The natural history and surgical behavior of meningiomas in octogenarians are not well understood. We evaluated the surgical and functional outcomes, including survival, among octogenarians with intracranial meningiomas in a single institution. METHODS: The Tumor Registry (2004-2021) was used to identify octogenarian patients (ages 80-89) diagnosed with intracranial meningioma. Primary endpoints were 1-year survival and functional outcome measured with mRS postsurgery. Kaplan-Meier, univariable Log-rank tests, and multivariable Cox hazards proportional regression models were used for assessing factors associated with overall survival (OS) in octogenarians with meningiomas who underwent surgery; logistic regression and McNemar's were used to further characterize risk factors affecting functional surgical outcome at 1 year. RESULTS: Thirty octogenarians with intracranial meningioma who underwent surgery were identified. Median age was 82.5 years and 66.6% were female patients. The 1-year median postsurgical survival probability for all octogenarians with meningioma was 86.3% and no intraoperative mortality was observed. Frailty (mFI-5, p = 0.84), tumor grade (p = 0.11), tumor size (p = 0.22), extent of resection (p = 0.35), and Karnofsky scale on admission (p = 0.93) did not significantly affect the survival in octogenarians with meningiomas which were treated surgically. The 1-year postoperative functional status of octogenarian meningioma patients who underwent surgery was significantly improved compared to pre-op mRS (McNemar's chi-squared = 9.6, df = 1, p-value = 0.001946). CONCLUSION: In octogenarians with meningiomas, surgical intervention significantly improves the pre-operative modified Rankin Scale at 1 year postsurgery in this cohort.


Assuntos
Neoplasias Meníngeas , Meningioma , Idoso de 80 Anos ou mais , Humanos , Feminino , Masculino , Meningioma/patologia , Octogenários , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Estudos Retrospectivos , Resultado do Tratamento
7.
Stroke ; 52(6): 2109-2114, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33971743

RESUMO

Background and Purpose: Patient selection for thrombectomy of acute ischemic stroke caused by large vessel occlusion in the delayed time window (>6 hours) is dependent on delineation of clinical-core mismatch or radiological target mismatch using perfusion imaging. Selection paradigms not involving advanced imaging and software processing may reduce time to treatment and broaden eligibility. We aim to develop a conversion factor to approximately determine the volume of hypoperfused tissue using the National Institutes of Health Stroke Scale (NIHSS) score (clinically approximated hypoperfused tissue [CAT] volume) and explore its ability to identify patients eligible for thrombectomy in the late-time window. Methods: We performed a retrospective analysis of anterior circulation large vessel occlusion strokes at 3 comprehensive stroke centers. Demographic, clinical, and imaging (computed tomography perfusion processed using RAPID, IschemaView) information was analyzed. A conversion factor, which is a multiple of the NIHSS score (for NIHSS score <10 and ≥10), was derived from an initial cohort to calculate CAT volumes. Accuracy of CAT-based thrombectomy eligibility criteria (using CAT volume instead of Tmax >6 seconds volume) was tested using DEFUSE-3 criteria (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) eligibility as a gold standard in an independent cohort. Results: Of the 309 large vessel occlusion strokes (age, 70±14, 46% male, median NIHSS 16 [12­20]) included in this study, 38% of patients arrived beyond 6 hours of time from last known well. Conversion factors derived (derivation cohort-center A: 187) based on median values of Tmax>6 second volume for NIHSS score <10 subgroup was 15 and for NIHSS score ≥10 subgroup was 6. Subsequently calculated CAT volume­based eligibility criteria yielded a sensitivity of 100% and specificity of 92% in detecting DEFUSE-3 eligible patients (area under the curve, 0.92 [95% CI, 0.82­1]) in the validation cohort (center B and C:122). Conclusions: Clinical severity of stroke (NIHSS score) may be used to calculate the volume of hypoperfused tissue during large vessel occlusion stroke. CAT volumes for NIHSS score <10 (using a factor of 15) and ≥10 (using a factor of 6) subgroups can accurately identify DEFUSE-3-eligible patients.


Assuntos
Volume Sanguíneo Cerebral , AVC Isquêmico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Stroke ; 52(3): 1022-1029, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33535778

RESUMO

BACKGROUND AND PURPOSE: The optimal endovascular stroke therapy (EVT) care delivery structure is unknown. Here, we present our experience in creating an integrated stroke system (ISS) to expand EVT availability throughout our region while maintaining hospital and physician quality standards. METHODS: We identified all consecutive patients with large vessel occlusion acute ischemic stroke treated with EVT from January 2014 to February 2019 in our health care system. In October 2017, we implemented the ISS, in which 3 additional hospitals (4 total) became EVT-performing hospitals (EPHs) and physicians were rotated between all centers. The cohort was divided by time into pre-ISS and post-ISS, and the primary outcome was time from stroke onset to EPH arrival. Secondary outcomes included hospital and procedural quality metrics. We performed an external validation using data from the Southeast Texas Regional Advisory Council. RESULTS: Among 513 patients with large vessel occlusion acute ischemic stroke treated with EVT, 58% were treated pre-ISS and 43% post-ISS. Over the study period, EVT procedural volume increased overall but remained relatively low at the 3 new EPHs (<70 EVT/y). After ISS, the proportion of patients who underwent interhospital transfer decreased (46% versus 37%; P<0.05). In adjusted quantile regression, ISS implementation resulted in a reduction of time from stroke onset to EPH arrival by 40 minutes (P<0.01) and onset to groin puncture by 29 minutes (P<0.05). Rates of postprocedural hemorrhage, modified Thrombolysis in Cerebral Infarction (TICI) 2b/3, and 90-day modified Rankin Scale were comparable at the higher and lower volume EPHs. The improvement in onset-to-arrival time was not reflective of overall improvement in secular trends in regional prehospital care. CONCLUSIONS: In our system, increasing EVT availability decreased time from stroke onset to EPH arrival. The ISS provides a framework to maintain quality in lower volume hospitals.


Assuntos
Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Idoso , Isquemia Encefálica/terapia , Feminino , Hemorragia , Hospitais , Humanos , AVC Isquêmico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Reprodutibilidade dos Testes , Trombectomia , Resultado do Tratamento
9.
Acta Neurochir (Wien) ; 163(1): 161-168, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32533411

RESUMO

BACKGROUND: Patients with cerebral vasospasm caused by aneurysmal subarachnoid hemorrhage (aSAH) are often treated with intra-arterial (IA) vasodilator infusion. However, the optimal drug regimen is yet to be elucidated. METHODS: A retrospective review of patients with aSAH and cerebral vasospasm treated with IA vasodilator infusion was performed. Patients in group 1 (2008-2011) were treated with a single agent, either nicardipine or verapamil, and patients in group 2 (2010-2016) were treated with a regimen of nitroglycerin, verapamil, and nicardipine. The post-infusion improvement ratio (PIIR) was compared between groups. Adjusted multivariate logistic regression models were utilized to determine whether patients treated with multiple vasodilators had an improved functional outcome, defined by the modified Rankin Scale, at discharge and 90-day follow-up. RESULTS: Among 116 patients from group 1 (N = 47) and group 2 (N = 69), the median age was 54.5 years [IQR, 46-53 years] and 78% were female. Use of multiple-agent therapy resulted in a 24.36% improvement in vessel diameter over single-agent therapy (median PIIR: group 1, 10.5% [IQR, 5.3-21.1%] vs group 2, 34.9% [IQR, 21.4-66.0%]; p < 0.0001). In the adjusted multivariate logistic regression, the use of multiple-agent therapy was associated with a better functional outcome at discharge (OR 0.15, 95% CI [0.04-0.55]; p < 0.01) and at 90-day follow-up (OR 0.20, 95% CI [0.05-0.77]; p < 0.05) when compared to single-agent therapy. CONCLUSION: In this study, we found that patients treated for cerebral vasospasm with IA infusion of multiple vasodilators had an increased vessel response and better functional outcomes compared to those treated with a single agent.


Assuntos
Nicardipino/administração & dosagem , Hemorragia Subaracnóidea/complicações , Vasodilatadores/administração & dosagem , Vasoespasmo Intracraniano/tratamento farmacológico , Verapamil/administração & dosagem , Feminino , Humanos , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Nitroglicerina/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento , Vasoespasmo Intracraniano/etiologia
10.
J Stroke Cerebrovasc Dis ; 30(12): 106131, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34655973

RESUMO

OBJECTIVES: Previous studies have shown racial disparities in access to treatment and outcomes in ischemic stroke patients. We sought to define racial disparities in functional outcomes among ischemic stroke patients receiving endovascular thrombectomy (EVT). MATERIALS AND METHODS: We performed a retrospective review of patients in our institution's prospectively collected stroke patient registry from 08/2015 to 06/2019 at 1 comprehensive and 2 thrombectomy-ready stroke centers. We reviewed patients aged ≥ 18 who received mechanical thrombectomy including only patients with race/ethnicity data belonging to the 3 largest race/ethnic groups: Non-Hispanic White (NHW), Non-Hispanic Black (NHB), and Hispanic (HIS). We compared baseline characteristics and performed multivariable logistic regression to evaluate differences in good functional outcome defined as 90-day modified Rankin score (90 day mRS 0-2) as the primary outcome. Secondary outcomes were discharge disposition, length of stay, and excellent functional outcome (90 day mRS 0-1). Results are given as OR [95% CI]. RESULTS: Among 666 patients that met inclusion criteria, 45% were NHW, 30% were NHB, and 19% were HIS. NHB and HIS patients were younger than NHW (average age NHB 62; HIS 64; and NHW 70; p < 0.001). Diabetes was more prevalent in NHB (32%, p = 0.02) and HIS (47%, p < 0.001) compared to NHW (23%). There were no significant racial differences in pre-morbid mRS, arrival NIHSS, tPA treatment rates. There was no difference in primary outcome by race comparing NHW to the other racial groups (OR 1.08 [0.68-1.72]) but compared to HIS patients, NHW had a higher likelihood of the secondary outcome of excellent functional outcome (aOR 2.23 [1.01-4.93]) defined as mRS 0-1. CONCLUSIONS: In this study of over 600 patients treated with EVT, we did not find significant racial disparities in functional outcome except for less excellent functional outcome in HIS compared to NHW. Further study on disparities in post-acute stroke care is needed.


Assuntos
Etnicidade , Disparidades nos Níveis de Saúde , AVC Isquêmico , Grupos Raciais , Trombectomia , Negro ou Afro-Americano/estatística & dados numéricos , Idoso , Etnicidade/estatística & dados numéricos , Hispânico ou Latino/estatística & dados numéricos , Humanos , AVC Isquêmico/etnologia , AVC Isquêmico/fisiopatologia , AVC Isquêmico/cirurgia , Pessoa de Meia-Idade , Grupos Raciais/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento , População Branca/estatística & dados numéricos
11.
J Stroke Cerebrovasc Dis ; 30(6): 105775, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33839380

RESUMO

OBJECTIVES: Embolic stroke is a frequent complication of infective endocarditis yet lacks acute treatment as intravenous thrombolysis should be avoided due to high risk of intracerebral hemorrhage. Mechanical thrombectomy for large vessel occlusion may be a promising treatment but there is limited data on safety outcomes in infective endocarditis. MATERIALS AND METHODS: In this multi-center retrospective case series, we reviewed data from patients with infective endocarditis-related large vessel occlusion who underwent mechanical thrombectomy in 9 US hospitals. RESULTS: We identified 15 patients at 9 hospitals. A minority presented with signs suggesting infection (2 patients (14%) had fever, 7 (47%) were tachycardic, 2 (13%) were hypotensive, and 8 (53%) had leukocytosis). The median National Institute of Health Stroke Score decreased from 19 (range 9-25) at presentation to 7 post-thrombectomy (range 0-22, median best score post-thrombectomy), and the median modified Rankin Scale on or after discharge for survivors was 3 (range 0-6). Approximately 57% of patients had a modified Rankin Scale between 0 and 3 on or after discharge. Hemorrhagic transformation was observed in 7/15 (47%). The mechanical thrombectomy group had 2/9 petechial hemorrhagic transformation (22%), compared to 4/6 parenchymal hematomas (67%) in the tissue plasminogen activator + mechanical thrombectomy group. CONCLUSIONS: Our findings suggest that patients with large vessel occlusion due to infective endocarditis may not present with overt signs of infection. Mechanical thrombectomy may be an effective treatment in this patient population for whom intravenous thrombolysis should be avoided.


Assuntos
AVC Embólico/terapia , Endocardite/complicações , Procedimentos Endovasculares , Trombectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Avaliação da Deficiência , AVC Embólico/diagnóstico , AVC Embólico/etiologia , AVC Embólico/fisiopatologia , Endocardite/diagnóstico , Procedimentos Endovasculares/efeitos adversos , Feminino , Estado Funcional , Humanos , Hemorragias Intracranianas/etiologia , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica , Estudos Retrospectivos , Trombectomia/efeitos adversos , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
12.
Stroke ; 51(10): 3055-3063, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32878563

RESUMO

BACKGROUND AND PURPOSE: Noncontrast head CT and CT perfusion (CTP) are both used to screen for endovascular stroke therapy (EST), but the impact of imaging strategy on likelihood of EST is undetermined. Here, we examine the influence of CTP utilization on likelihood of EST in patients with large vessel occlusion (LVO). METHODS: We identified patients with acute ischemic stroke at 4 comprehensive stroke centers. All 4 hospitals had 24/7 CTP and EST capability and were covered by a single physician group (Neurology, NeuroIntervention, NeuroICU). All centers performed noncontrast head CT and CT angiography in the initial evaluation. One center also performed CTP routinely with high CTP utilization (CTP-H), and the others performed CTP optionally with lower utilization (CTP-L). Primary outcome was likelihood of EST. Multivariable logistic regression was used to determine whether facility type (CTP-H versus CTP-L) was associated with EST adjusting for age, prestroke mRS, National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, LVO location, time window, and intravenous tPA (tissue-type plasminogen activator). RESULTS: Among 3107 patients with acute ischemic stroke, 715 had LVO, of which 403 (56%) presented to CTP-H and 312 (44%) presented to CTP-L. CTP utilization among LVO patients was greater at CTP-H centers (72% versus 18%, CTP-H versus CTP-L, P<0.01). In univariable analysis, EST rates for patients with LVO were similar between CTP-H versus CTP-L (46% versus 49%). In multivariable analysis, patients with LVO were less likely to undergo EST at CTP-H (odds ratio, 0.59 [0.41-0.85]). This finding was maintained in multiple patient subsets including late time window, anterior circulation LVO, and direct presentation patients. Ninety-day functional independence (odds ratio, 1.04 [0.70-1.54]) was not different, nor were rates of post-EST PH-2 hemorrhage (1% versus 1%). CONCLUSIONS: We identified an increased likelihood for undergoing EST in centers with lower CTP utilization, which was not associated with worse clinical outcomes or increased hemorrhage. These findings suggest under-treatment bias with routine CTP.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/diagnóstico por imagem , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/tratamento farmacológico , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/tratamento farmacológico , Tomografia Computadorizada por Raios X , Resultado do Tratamento
13.
Microbiology (Reading) ; 166(3): 278-287, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31935179

RESUMO

In nitrogen-fixing rhizobia, emerging evidence shows significant roles for polyamines in growth and abiotic stress resistance. In this work we show that a polyamine-deficient ornithine decarboxylase null mutant (odc2) derived from Sinorhizobium meliloti Rm8530 had significant phenotypic differences from the wild-type, including greatly reduced production of exopolysaccharides (EPS; ostensibly both succinoglycan and galactoglucan), increased sensitivity to oxidative stress and decreased swimming motility. The introduction of the odc2 gene borne on a plasmid into the odc2 mutant restored wild-type phenotypes for EPS production, growth under oxidative stress and swimming. The production of calcofluor-binding EPS (succinoglycan) by the odc2 mutant was also completely or mostly restored in the presence of exogenous spermidine (Spd), norspermidine (NSpd) or spermine (Spm). The odc2 mutant formed about 25 % more biofilm than the wild-type, and its ability to form biofilm was significantly inhibited by exogenous Spd, NSpd or Spm. The odc2 mutant formed a less efficient symbiosis with alfalfa, resulting in plants with significantly less biomass and height, more nodules but less nodule biomass, and 25 % less nitrogen-fixing activity. Exogenously supplied Put was not able to revert these phenotypes and caused a similar increase in plant height and dry weight in uninoculated plants and in those inoculated with the wild-type or odc2 mutant. We discuss ways in which polyamines might affect the phenotypes of the odc2 mutant.


Assuntos
Medicago sativa/microbiologia , Ornitina Descarboxilase/genética , Poliaminas/metabolismo , Nódulos Radiculares de Plantas , Sinorhizobium meliloti/genética , Proteínas de Bactérias/genética , Medicago sativa/crescimento & desenvolvimento , Medicago sativa/metabolismo , Mutação , Nitrogênio/metabolismo , Fenótipo , Polissacarídeos Bacterianos/metabolismo , Nódulos Radiculares de Plantas/metabolismo , Nódulos Radiculares de Plantas/microbiologia , Sinorhizobium meliloti/metabolismo
14.
Blood ; 132(4): 393-404, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-29567798

RESUMO

Ponatinib has potent activity against native and mutant BCR-ABL1, including BCR-ABL1T315I The pivotal phase 2 Ponatinib Ph+ ALL and CML Evaluation (PACE) trial evaluated efficacy and safety of ponatinib at a starting dose of 45 mg once daily in 449 patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) resistant/intolerant to dasatinib or nilotinib, or with BCR-ABL1T315I This analysis focuses on chronic-phase CML (CP-CML) patients (n = 270) with 56.8-month median follow-up. Among 267 evaluable patients, 60%, 40%, and 24% achieved major cytogenetic response (MCyR), major molecular response (MMR), and 4.5-log molecular response, respectively. The probability of maintaining MCyR for 5 years was 82% among responders. Dose reductions were implemented in October 2013 to decrease the risk of arterial occlusive events (AOEs); ≥90% of CP-CML patients who had achieved MCyR or MMR maintained response 40 months after elective dose reductions. Estimated 5-year overall survival was 73%. In CP-CML patients, the most common treatment-emergent adverse events were rash (47%), abdominal pain (46%), thrombocytopenia (46%), headache (43%), dry skin (42%), and constipation (41%). The cumulative incidence of AOEs in CP-CML patients increased over time to 31%, while the exposure-adjusted incidence of new AOEs (15.8 and 4.9 per 100 patient-years in years 1 and 5, respectively) did not increase over time. These final PACE results demonstrate ponatinib provides durable and clinically meaningful responses, irrespective of dose reductions, in this population of heavily pretreated CP-CML patients. This trial was registered at www.clinicaltrials.gov as #NCT01207440.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Imidazóis/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Cromossomo Filadélfia , Piridazinas/uso terapêutico , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Seguimentos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Segurança , Taxa de Sobrevida , Fatores de Tempo , Adulto Jovem
15.
J Neurooncol ; 148(2): 389-397, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32440969

RESUMO

INTRODUCTION: Glioblastomas (GBMs) usually occur as a solitary lesion; however, about 0.5-35% present with multiple lesions (M-GBM). The genetic landscape of GBMs have been thoroughly investigated; nevertheless, differences between M-GBM and single-foci GBM (S-GBM) remains unclear. The present study aimed to determine differences in clinical and molecular characteristics between M-GBM and S-GBM. METHODS: A retrospective review of multifocal/multicentric infiltrative gliomas (M-IG) from our institutional database was performed. Demographics, clinical, radiological, and genetic features were obtained and compared between M-GBM IDH-wild type (IDH-WT) vs 193 S-GBM IDH-WT. Mutations were examined by a targeted next-generation sequencing assay interrogating 315 genes. RESULTS: 33M-IG were identified from which 94% were diagnosed as M-GBM IDH-WT, the remaining 6% were diagnosed as astrocytomas IDH-mutant. M-GBM and S-GBM comparison revealed that EGFR alterations were more frequent in M-GBM (65% vs 42% p = 0.019). Furthermore, concomitant EGFR/PTEN alterations were more common in M-GBM vs. S-GBM (36% vs 19%) as well as compared to TCGA (21%). No statistically significant differences in overall survival were observed between M-GBM and S-GBM; however, within the M-GBM cohort, patients harboring KDR alterations had a worse survival (KDR-altered 6.7 vs KDR-WT 16.6 months, p = 0.038). CONCLUSIONS: The results of the present study demonstrate that M-GBM genetically resembles S-GBM, however, M-GBM harbor higher frequency of EGFR alterations and co-occurrence of EGFR/PTEN alterations, which may account for their highly malignant and invasive phenotype. Further study of genetic alterations including differences between multifocal and multicentric GBMs are warranted, which may identify potential targets for this aggressive tumor.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioblastoma/genética , Glioblastoma/patologia , Idoso , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Retrospectivos
16.
Stroke ; 50(11): 3093-3100, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31547796

RESUMO

Background and Purpose- The availability of and expertise to interpret advanced neuroimaging recommended in the guideline-based endovascular stroke therapy (EST) evaluation are limited. Here, we develop and validate an automated machine learning-based method that evaluates for large vessel occlusion (LVO) and ischemic core volume in patients using a widely available modality, computed tomography angiogram (CTA). Methods- From our prospectively maintained stroke registry and electronic medical record, we identified patients with acute ischemic stroke and stroke mimics with contemporaneous CTA and computed tomography perfusion (CTP) with RAPID (IschemaView) post-processing as a part of the emergent stroke workup. A novel convolutional neural network named DeepSymNet was created and trained to identify LVO as well as infarct core from CTA source images, against CTP-RAPID definitions. Model performance was measured using 10-fold cross validation and receiver-operative curve area under the curve (AUC) statistics. Results- Among the 297 included patients, 224 (75%) had acute ischemic stroke of which 179 (60%) had LVO. Mean CTP-RAPID ischemic core volume was 23±42 mL. LVO locations included internal carotid artery (13%), M1 (44%), and M2 (21%). The DeepSymNet algorithm autonomously learned to identify the intracerebral vasculature on CTA and detected LVO with AUC 0.88. The method was also able to determine infarct core as defined by CTP-RAPID from the CTA source images with AUC 0.88 and 0.90 (ischemic core ≤30 mL and ≤50 mL). These findings were maintained in patients presenting in early (0-6 hours) and late (6-24 hours) time windows (AUCs 0.90 and 0.91, ischemic core ≤50 mL). DeepSymNet probabilities from CTA images corresponded with CTP-RAPID ischemic core volumes as a continuous variable with r=0.7 (Pearson correlation, P<0.001). Conclusions- These results demonstrate that the information needed to perform the neuroimaging evaluation for endovascular therapy with comparable accuracy to advanced imaging modalities may be present in CTA, and the ability of machine learning to automate the analysis.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Bases de Dados Factuais , Aprendizado Profundo , Diagnóstico por Computador , Registros Eletrônicos de Saúde , Redes Neurais de Computação , Neuroimagem , Sistema de Registros , Acidente Vascular Cerebral/diagnóstico por imagem , Doença Aguda , Idoso , Isquemia Encefálica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acidente Vascular Cerebral/terapia
17.
Luminescence ; 34(8): 859-869, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31347246

RESUMO

Increasing numbers of studies are using Aliivibrio fischeri (A. fischeri), a marine bioluminescent bacterium as a model, however the culture medium used for its growth are complex and expensive. The objectives of this study were: (1) to evaluate the effect of yeast extract, tryptone, and NaCl to select a simple and inexpensive culture medium suitable for A. fischeri growth and bioluminescence induction; and (2) to compare the performance of mathematical models to predict the growth of A. fischeri. A fractional factorial design was performed to evaluate the effect of yeast extract, tryptone, and sodium chloride on the luminescence of A. fischeri. The result showed that sodium chloride is the most important factor, congruent with its inducer role in bioluminescence. The best medium for bioluminescence induction was selected through an optimization plot, this medium is inexpensive, and generates the same luminescence as commercial formulations. The estimation of A. fischeri growth at OD600 measurement was statistically analyzed. All evaluated models fitted the data adequately (r2  > 0.96). The nonlinear models Gompertz, Richards and logistic provided a lower variation and a better fit of the growth estimation (r2 >0.99), showing that these mathematical models can be used for the accurate growth prediction of A. fischeri.


Assuntos
Aliivibrio fischeri/crescimento & desenvolvimento , Aliivibrio fischeri/isolamento & purificação , Medições Luminescentes , Modelos Estatísticos , Modelos Lineares , Software
18.
Crit Care Nurs Q ; 42(3): 292-303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31135480

RESUMO

Every year, sepsis affects nearly 30 million people worldwide, with current annual estimates reporting as many as 6 million deaths. To combat the staggering number of patients who are affected by sepsis, clinicians continue to investigate novel treatment approaches. One treatment approach that has gained interest is the role that vitamins and nutrients play in the body's response to sepsis. Thiamine, in particular, has been studied because of its role in glucose metabolism and lactate production. This review provides a summary of the current literature surrounding the use of thiamine in the treatment of sepsis and describes the function of this essential nutrient in sepsis pathology. We also aim to provide clinicians with the necessary understanding to recognize the potential for thiamine deficiency, as well as detail the role of thiamine supplementation in the treatment of sepsis.


Assuntos
Sepse/tratamento farmacológico , Tiamina/uso terapêutico , Humanos , Sepse/complicações , Deficiência de Tiamina/prevenção & controle
19.
Microbiology (Reading) ; 164(4): 600-613, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29619919

RESUMO

Polyamines (PAs) are ubiquitous polycations derived from basic l-amino acids whose physiological roles are still being defined. Their biosynthesis and functions in nitrogen-fixing rhizobia such as Sinorhizobium meliloti have not been extensively investigated. Thin layer chromatographic and mass spectrometric analyses showed that S. meliloti Rm8530 produces the PAs, putrescine (Put), spermidine (Spd) and homospermidine (HSpd), in their free forms and norspermidine (NSpd) in a form bound to macromolecules. The S. meliloti genome encodes two putative ornithine decarboxylases (ODC) for Put synthesis. Activity assays with the purified enzymes showed that ODC2 (SMc02983) decarboxylates both ornithine and lysine. ODC1 (SMa0680) decarboxylates only ornithine. An odc1 mutant was similar to the wild-type in ODC activity, PA production and growth. In comparison to the wild-type, an odc2 mutant had 45 % as much ODC activity and its growth rates were reduced by 42, 14 and 44 % under non-stress, salt stress or acid stress conditions, respectively. The odc2 mutant produced only trace levels of Put, Spd and HSpd. Wild-type phenotypes were restored when the mutant was grown in cultures supplemented with 1 mM Put or Spd or when the odc2 gene was introduced in trans. odc2 gene expression was increased under acid stress and reduced under salt stress and with exogenous Put or Spd. An odc1 odc2 double mutant had phenotypes similar to the odc2 mutant. These results indicate that ODC2 is the major enzyme for Put synthesis in S. meliloti and that PAs are required for normal growth in vitro.


Assuntos
Ornitina Descarboxilase/metabolismo , Poliaminas/metabolismo , Sinorhizobium meliloti/crescimento & desenvolvimento , Sinorhizobium meliloti/metabolismo , Aminoácidos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Meios de Cultura , Regulação Bacteriana da Expressão Gênica , Teste de Complementação Genética , Mutação , Ornitina Descarboxilase/genética , Poliaminas/análise , Putrescina/metabolismo , Sinorhizobium meliloti/enzimologia , Espermidina/análogos & derivados , Espermidina/metabolismo , Transcrição Gênica
20.
Blood ; 127(15): 1870-80, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26773037

RESUMO

The third-generation tyrosine kinase inhibitor (TKI) ponatinib shows activity against all common BCR-ABL1 single mutants, including the highly resistant BCR-ABL1-T315I mutant, improving outcome for patients with refractory chronic myeloid leukemia (CML). However, responses are variable, and causal baseline factors have not been well-studied. The type and number of low-level BCR-ABL1 mutations present after imatinib resistance has prognostic significance for subsequent treatment with nilotinib or dasatinib as second-line therapy. We therefore investigated the impact of low-level mutations detected by sensitive mass-spectrometry before ponatinib initiation (baseline) on treatment response in 363 TKI-resistant patients enrolled in the PONATINIB for Chronic Myeloid Leukemia Evaluation and Ph(+)Acute Lymphoblastic Leukemia trial, including 231 patients in chronic phase (CP-CML). Low-level mutations were detected in 53 patients (15%, including low-level T315I in 14 patients); most, however, did not undergo clonal expansion during ponatinib treatment and, moreover, no specific individual mutations were associated with inferior outcome. We demonstrate however, that the number of mutations detectable by mass spectrometry after TKI resistance is associated with response to ponatinib treatment and could be used to refine the therapeutic approach. Although CP-CML patients with T315I (63/231, 27%) had superior responses overall, those with multiple mutations detectable by mass spectrometry (20, 32%) had substantially inferior responses compared with those with T315I as the sole mutation detected (43, 68%). In contrast, for CP-CML patients without T315I, the inferior responses previously observed with nilotinib/dasatinib therapy for imatinib-resistant patients with multiple mutations were not seen with ponatinib treatment, suggesting that ponatinib may prove to be particularly advantageous for patients with multiple mutations detectable by mass spectrometry after TKI resistance.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas de Fusão bcr-abl/genética , Imidazóis/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Mutação , Piridazinas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , Resistencia a Medicamentos Antineoplásicos , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Inibidores de Proteínas Quinases/uso terapêutico , Resultado do Tratamento , Adulto Jovem
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