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1.
Sens Int ; 2: 100088, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34766050

RESUMO

The deadly corona virus continues to pound the globe mercilessly compelling mathematical models and computational simulations which might prove effective tools to enable global efforts to estimate key transmission parameters involved in the system. We propose a mathematical model using a set of non-linear differential equations to account for the spread of the COVID-19 infection with special compartment class isolation or quarantine and estimate the model parameters by fitting the model with reported data of the ongoing pandemic situation in India. The basic reproduction number is defined and local stability analysis is carried out at each equilibrium point in terms of the reproduction number R 0 . The model is fitted mathematically and makes the data India specific. Additionally, we examined sensitivity analysis of the model. These outcomes recommend how to control the spread of corona, keeping in mind contact and recovery rate. Also we have investigated the elasticity of the basic reproduction number as a measure of control parameters of the dynamical system. Numerical simulations were also done to show that the proposed model is valid for the type and spread of the outbreak which happened in India.

2.
J Neural Eng ; 15(1): 016009, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28914232

RESUMO

OBJECTIVE: Combining repetitive transcranial magnetic stimulation (rTMS) with brain-computer interface (BCI) training can address motor impairment after stroke by down-regulating exaggerated inhibition from the contralesional hemisphere and encouraging ipsilesional activation. The objective was to evaluate the efficacy of combined rTMS + BCI, compared to sham rTMS + BCI, on motor recovery after stroke in subjects with lasting motor paresis. APPROACH: Three stroke subjects approximately one year post-stroke participated in three weeks of combined rTMS (real or sham) and BCI, followed by three weeks of BCI alone. Behavioral and electrophysiological differences were evaluated at baseline, after three weeks, and after six weeks of treatment. MAIN RESULTS: Motor improvements were observed in both real rTMS + BCI and sham groups, but only the former showed significant alterations in inter-hemispheric inhibition in the desired direction and increased relative ipsilesional cortical activation from fMRI. In addition, significant improvements in BCI performance over time and adequate control of the virtual reality BCI paradigm were observed only in the former group. SIGNIFICANCE: When combined, the results highlight the feasibility and efficacy of combined rTMS + BCI for motor recovery, demonstrated by increased ipsilesional motor activity and improvements in behavioral function for the real rTMS + BCI condition in particular. Our findings also demonstrate the utility of BCI training alone, as shown by behavioral improvements for the sham rTMS + BCI condition. This study is the first to evaluate combined rTMS and BCI training for motor rehabilitation and provides a foundation for continued work to evaluate the potential of both rTMS and virtual reality BCI training for motor recovery after stroke.


Assuntos
Interfaces Cérebro-Computador , Córtex Motor/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Estimulação Magnética Transcraniana/métodos , Terapia de Exposição à Realidade Virtual/métodos , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia
3.
Methods Mol Biol ; 883: 121-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22589129

RESUMO

The ribonuclease protection assay (RPA) has emerged as an important methodology for the detection, mapping, and quantification of RNAs. In this assay, total or cytoplasmic RNAs are hybridized to a high-specific activity antisense radioactive RNA probe synthesized by in vitro transcription from the SP6 or T7 promoter of an appropriate linearized plasmid template by the bacteriophage SP6 or T7 polymerase, respectively. The RNA hybrids are subjected to RNAse digestion and the protected products are resolved by denaturing polyacrylamide gel electrophoresis to allow detection of specific RNA fragments by subsequent autoradiography. RPAs are highly sensitive, the probes can be specifically targeted, and, when performed in probe excess, are quantitative, making them the method of choice for many analyses of RNA processing events.


Assuntos
Isoformas de RNA/genética , RNA Mensageiro/genética , Análise de Sequência de RNA/métodos , Animais , Autorradiografia , Células Cultivadas , Eletroforese em Gel de Poliacrilamida/métodos , Humanos , Desnaturação de Ácido Nucleico , Hibridização de Ácido Nucleico , Radioisótopos de Fósforo , Clivagem do RNA , Isoformas de RNA/química , Sondas RNA , Processamento Pós-Transcricional do RNA , RNA Mensageiro/química , Ribonuclease T1 , Ribonuclease Pancreático , Ribonucleases , Coloração e Rotulagem , Transcrição Gênica
4.
Neurology ; 74(20): 1634-42, 2010 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-20479363

RESUMO

OBJECTIVE: We evaluated the effect of performance feedback on acute ischemic stroke care quality in Minnesota hospitals. METHODS: A cluster-randomized controlled trial design with hospital as the unit of randomization was used. Care quality was defined as adherence to 10 performance measures grouped into acute, in-hospital, and discharge care. Following preintervention data collection, all hospitals received a report on baseline care quality. Additionally, in experimental hospitals, clinical opinion leaders delivered customized feedback to care providers and study personnel worked with hospital administrators to implement changes targeting identified barriers to stroke care. Multilevel models examined experimental vs control, preintervention and postintervention performance changes and secular trends in performance. RESULTS: Nineteen hospitals were randomized with a total of 1,211 acute ischemic stroke cases preintervention and 1,094 cases postintervention. Secular trends were significant with improvement in both experimental and control hospitals for acute (odds ratio = 2.7, p = 0.007) and in-hospital (odds ratio = 1.5, p < 0.0001) care but not discharge care. There was no significant intervention effect for acute, in-hospital, or discharge care. CONCLUSION: There was no definite intervention effect: both experimental and control hospitals showed significant secular trends with performance improvement. Our results illustrate the potential fallacy of using historical controls for evaluating quality improvement interventions. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that informing hospital leaders of compliance with ischemic stroke quality indicators followed by a structured quality improvement intervention did not significantly improve compliance more than informing hospital leaders of compliance with stroke quality indicators without a quality improvement intervention.


Assuntos
Fidelidade a Diretrizes/normas , Hospitais/normas , Qualidade da Assistência à Saúde/normas , Acidente Vascular Cerebral/terapia , Gestão da Qualidade Total/normas , Distribuição de Qui-Quadrado , Pesquisas sobre Atenção à Saúde , Humanos , Análise de Intenção de Tratamento , Razão de Chances , Estados Unidos
5.
AJNR Am J Neuroradiol ; 29(10): 1918-24, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18784214

RESUMO

BACKGROUND AND PURPOSE: Since the introduction of recombinant tissue plasminogen activator (rtPA) into clinical practice in the mid 1990s, no adjunctive treatment has further improved clinical outcomes in patients with ischemic stroke. The safety, feasibility, and efficacy of combining intravenous (IV) rtPA with endovascular interventions has been described; however, no direct comparative study has yet established whether endovascular interventions after IV rtPA are superior to IV rtPA alone. A retrospective case-control study was designed to address this issue. MATERIALS AND METHODS: Between 2003 and 2006, 33 consecutive patients with acute ischemic stroke and National Institutes of Health Stroke Scale (NIHSS) scores >/=10 were treated with IV rtPA in combination with endovascular interventions (IV plus intervention) at a tertiary care facility. Outcomes were compared with a control cohort of 30 consecutive patients treated with IV rtPA (IV only) at a comparable facility where endovascular interventions were not available. RESULTS: Baseline parameters were similar between the 2 groups. We found that the IV-plus-intervention group experienced significantly lower mortality at 90 days (12.1% versus 40.0%, P = .019) with a significantly greater improvement in NIHSS scores by the time of discharge or follow-up (P = .025). In the IV-plus-intervention group, patients with admission NIHSS scores between 10 and 15 and patients /=10, there was a suggestion of incremental clinical benefit among patients receiving endovascular interventions following standard administration of IV rtPA.


Assuntos
Isquemia Encefálica/mortalidade , Isquemia Encefálica/terapia , Embolização Terapêutica/estatística & dados numéricos , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/estatística & dados numéricos , Ativador de Plasminogênio Tecidual/administração & dosagem , Doença Aguda , Idoso , Estudos de Casos e Controles , Terapia Combinada/mortalidade , Terapia Combinada/estatística & dados numéricos , Embolização Terapêutica/mortalidade , Feminino , Humanos , Injeções Intravenosas , Masculino , Minnesota/epidemiologia , Proteínas Recombinantes/administração & dosagem , Recuperação de Função Fisiológica , Análise de Sobrevida , Taxa de Sobrevida , Terapia Trombolítica/mortalidade , Ativador de Plasminogênio Tecidual/genética , Resultado do Tratamento
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