Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Clin Neurophysiol ; 161: 188-197, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38520799

RESUMO

OBJECTIVE: Corticospinal inhibitory mechanisms are relevant to functional recovery but remain poorly understood after spinal cord injury (SCI). Post-injury characteristics of contralateral silent period (CSP), a measure of corticospinal inhibition evaluated using transcranial magnetic stimulation (TMS), is inconsistent in literature. We envisioned that investigating CSP across muscles with varying degrees of weakness may be a reasonable approach to resolve inconsistencies and elucidate the relevance of corticospinal inhibition for upper extremity function following SCI. METHODS: We studied 27 adults with chronic C1-C8 SCI (age 48.8 ± 16.1 years, 3 females) and 16 able-bodied participants (age 33.2 ± 11.8 years, 9 females). CSP characteristics were assessed across biceps (muscle power = 3-5) and triceps (muscle power = 1-3) representing stronger and weaker muscles, respectively. We assessed functional abilities using the Capabilities of the Upper Extremity Test (CUE-T). RESULTS: Participants with chronic SCI had prolonged CSPs for biceps but delayed and diminished CSPs for triceps compared to able-bodied participants. Early-onset CSPs for biceps and longer, deeper CSPs for triceps correlated with better CUE-T scores. CONCLUSIONS: Corticospinal inhibition is pronounced for stronger biceps but diminished for weaker triceps muscle in SCI indicating innervation relative to the level of injury matters in the study of CSP. SIGNIFICANCE: Nevertheless, corticospinal inhibition or CSP holds relevance for upper extremity function following SCI.


Assuntos
Inibição Neural , Tratos Piramidais , Traumatismos da Medula Espinal , Estimulação Magnética Transcraniana , Extremidade Superior , Humanos , Feminino , Traumatismos da Medula Espinal/fisiopatologia , Masculino , Adulto , Pessoa de Meia-Idade , Tratos Piramidais/fisiopatologia , Extremidade Superior/fisiopatologia , Estimulação Magnética Transcraniana/métodos , Inibição Neural/fisiologia , Músculo Esquelético/fisiopatologia , Potencial Evocado Motor/fisiologia , Medula Cervical/fisiopatologia , Medula Cervical/lesões , Adulto Jovem , Vértebras Cervicais/fisiopatologia , Eletromiografia/métodos
2.
Pediatr Res ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365873

RESUMO

BACKGROUND AND OBJECTIVE: Congenital heart defects are known to be associated with increased odds of severe COVID-19. Congenital anomalies affecting other body systems may also be associated with poor outcomes. This study is an exhaustive assessment of congenital anomalies and odds of severe COVID-19 in pediatric patients. METHODS: Data were retrieved from the COVID-19 dataset of Cerner® Real-World Data for encounters from March 2020 to February 2022. Prior to matching, the data consisted of 664,523 patients less than 18 years old and 927,805 corresponding encounters with COVID-19 from 117 health systems across the United States. One-to-one propensity score matching was performed, and a cumulative link mixed-effects model with random intercepts for health system and patients was built to assess corresponding associations. RESULTS: All congenital anomalies were associated with worse COVID-19 outcomes, with the strongest association observed for cardiovascular anomalies (odds ratio [OR], 3.84; 95% CI, 3.63-4.06) and the weakest association observed for anomalies affecting the eye/ear/face/neck (OR, 1.16; 95% CI, 1.03-1.31). CONCLUSIONS AND RELEVANCE: Congenital anomalies are associated with greater odds of experiencing severe symptoms of COVID-19. In addition to congenital heart defects, all other birth defects may increase the odds for more severe COVID-19. IMPACT: All congenital anomalies are associated with increased odds of severe COVID-19. This study is the largest and among the first to investigate birth defects across all body systems. The multicenter large data and analysis demonstrate the increased odds of severe COVID19 in pediatric patients with congenital anomalies affecting any body system. These data demonstrate that all children with birth defects are at increased odds of more severe COVID-19, not only those with heart defects. This should be taken into consideration when optimizing prevention and intervention resources within a hospital.

3.
Int J Nanomedicine ; 17: 5581-5600, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36444195

RESUMO

Purpose: Peptide-based therapy is a promising strategy for cancer treatment because of its low drug resistance. However, the major challenge is their inability to target cancer cells specifically. So, a targeted nano-delivery system that could deliver therapeutic peptides selectively to cancer cells to stimulate their action is highly desirable. This study aims to deliver the antitumor peptide, Pep5, to breast tumor cells selectively using a targeting peptide functionalised multi-layered PLGA-PEI nanoparticles. Methods: In this study, Pep5 entrapped PLGA-PEI (Pep5-PPN) dual layered nanoparticles were developed. These nanoparticles were decorated with TKD (Pep5-TPPN) on their surface for site-specific delivery of Pep5 to breast tumor cells. The particles were then characterized using various instrumental analyses. In vitro cytotoxicity of the particles was evaluated in estrogen receptor positive (ER+ve) and triple negative breast cancer (TNBC) cells. An ex vivo tumor spheroid model was used to analyze the antitumor activity of the particles. Results: Uniformly round Pep5-TPPN particles were synthesized with an average diameter of 420.8 ± 14.72 nm. The conjugation of PEI over Pep5-PLGA nanoparticles shifted the zeta potential from -11.6 ± 2.16 mV to +20.01 ± 2.97 mV. In vitro cytotoxicity analysis proved that TKD conjugation to nanoparticles enhanced the antitumor activity of Pep5 in tested breast cancer cells. Pep5-TPPN induced cytoskeletal damage and apoptosis in the tested cells, which showed that the mechanism of action of Pep5 is conserved but potentiated. Active targeting of Pep5 suppressed the tumor growth in ex vivo spheroid models. Conclusion: A multi-layered nanoparticle functionalized with dual peptide was fabricated for active tumor targeting, which stimulated Pep5 activity to reduce the tumor growth in vitro and ex vivo.


Assuntos
Nanopartículas , Neoplasias de Mama Triplo Negativas , Humanos , Contagem de Células , Peptídeos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Citoesqueleto
4.
Front Neurol ; 13: 869733, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35599736

RESUMO

Background: Approximately two-thirds of stroke survivors experience chronic upper limb paresis, and of them, 50% experience severe paresis. Treatment options for severely impaired survivors are often limited. Rehabilitation involves intensively engaging the paretic upper limb, and disincentivizing use of the non-paretic upper limb, with the goal to increase excitability of the ipsilesional primary motor cortex (iM1) and suppress excitability of the undamaged (contralesional) motor cortices, presumed to have an inhibitory effect on iM1. Accordingly, brain stimulation approaches, such as repetitive transcranial magnetic stimulation (rTMS), are also given to excite iM1 and/or suppress contralesional motor cortices. But such approaches aimed at ultimately increasing iM1 excitability yield limited functional benefit in severely impaired survivors who lack sufficient ipsilesional substrate. Aim: Here, we test the premise that combining Contralaterally Controlled Functional Electrical Stimulation (CCFES), a rehabilitation technique that engages the non-paretic upper limb in delivery of neuromuscular electrical stimulation to the paretic upper limb, and a new rTMS approach that excites intact, contralesional higher motor cortices (cHMC), may have more favorable effect on paretic upper limb function in severely impaired survivors based on recruitment of spared, transcallosal and (alternate) ipsilateral substrate. Methods: In a prospective, double-blind, placebo-controlled RCT, 72 chronic stroke survivors with severe distal hand impairment receive CCFES plus cHMC rTMS, iM1 rTMS, or sham rTMS, 2X/wk for 12wks. Measures of upper limb motor impairment (Upper Extremity Fugl Meyer, UEFM), functional ability (Wolf Motor-Function Test, WMFT) and perceived disability are collected at 0, 6, 12 (end-of-treatment), 24, and 36 wks (follow-up). TMS is performed at 0, 12 (end-of-treatment), and 36 wks (follow-up) to evaluate inter-hemispheric and ipsilateral mechanisms. Influence of baseline severity is also characterized with imaging. Conclusions: Targeting of spared neural substrates and rehabilitation which engages the unimpaired limb in movement of the impaired limb may serve as a suitable combinatorial treatment option for severely impaired stroke survivors. ClinicalTrials No: NCT03870672.

5.
Cerebrovasc Dis ; 51(5): 557-564, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35051941

RESUMO

Up to 50% of stroke survivors have persistent, severe upper extremity paresis even after receiving rehabilitation. Repetitive transcranial magnetic stimulation (rTMS) can augment the effects of rehabilitation by modulating corticomotor excitability, but the conventional approach of facilitating excitability of the ipsilesional primary motor cortex (iM1) fails to produce motor improvement in stroke survivors with severe loss of ipsilesional substrate. Instead, the undamaged, contralesional dorsal premotor cortex (cPMd) may be a more suitable target. CPMd can offer alternate, bi-hemispheric and ipsilateral connections in support of paretic limb movement. This pilot, randomized clinical trial seeks to investigate whether rTMS delivered to facilitate cPMd in conjunction with rehabilitation produces greater gains in motor function than conventional rTMS delivered to facilitate iM1 in conjunction with rehabilitation in severely impaired stroke survivors. Twenty-four chronic (≥6 months) stroke survivors with severe loss of ipsilesional substrate (defined by the absence of physiologic evidence of excitable residual pathways tested using TMS) will be included. Participants will be randomized to receive rTMS to facilitate cPMd or iM1 in conjunction with task-oriented upper limb rehabilitation given for 2 sessions/week for 6 weeks. Assessments of primary outcome related to motor impairment (upper extremity Fugl-Meyer [UEFM]), motor function, neurophysiology, and functional neuroimaging will be made at baseline and at 6-week end-of-treatment. An additional assessment of motor outcomes will be repeated at 3-month follow-up to evaluate retention. The primary endpoint is 6-week change in UEFM. This pilot trial will provide preliminary evidence on the effects and mechanisms associated with facilitating intact cPMd in chronic severe stroke survivors. The trial is registered on clinicaltrials.gov, NCT03868410.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Projetos Piloto , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica/fisiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Reabilitação do Acidente Vascular Cerebral/métodos , Estimulação Magnética Transcraniana , Resultado do Tratamento , Extremidade Superior
6.
RSC Adv ; 11(17): 9807-9826, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35423526

RESUMO

Pyrolysis is a promising thermochemical strategy to convert scrap tires into diesel-like fuels. Crude tire pyrolysis oil (CTPO) was produced in a 10 ton rotating autoclave reactor by thermal depolymerization of the tire polymers. In this work, the prior-reported straightforward and inexpensive strategy of upgrading CTPO using a combination of silica gel (as adsorbent) and petroleum ether (as the solvent) has been scaled up with minimal loss in mass of oil and improved physicochemical characteristics (e.g., lowered acid value, low sulfur content). The upgraded TPO (StTPO) was characterized extensively to better understand their chemical compositions, physicochemical properties, and combustion characteristics. StTPO was mixed with diesel in different volumetric proportions and the blends were studied for performance and emission characteristics in a single-cylinder engine. The use of biomass-derived ethyl levulinate (EL) as a fuel oxygenate improved the cold-flow properties of StTPO-diesel blends as well as lowered the exhaust emissions (e.g., lower NO x ). A fuel blend consisting of 50% diesel, 40% StTPO, and 10% EL demonstrated the best fuel properties in the single-cylinder diesel engine.

7.
Asian J Neurosurg ; 15(3): 670-673, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33145225

RESUMO

Calvarial intradiploeic epidermal cyst are very rare neoplasms which can have intracranial extension. These cysts can attain a large size and can cause lytic destruction of the calvarium resembling malignancy. Since these lesions are benign complete excision is curative. We report the case of a 77-year-old male patient who presented with a large swelling on the forehead. Computed tomography and magnetic resonance imaging showed an expansile lytic lesion with intracranial extension. Complete excision of the lesion with cranioplasty was done. Histopathology was consistent with the epidermal cyst. These cysts attaining gigantic proportions are very few in literature.

8.
Surg Neurol Int ; 11: 261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33024599

RESUMO

BACKGROUND: Granular cell tumors (GCTs) of the pituitary are rare tumors of posterior pituitary that can present as giant pituitary macroadenoma due to the slow indolent growth of the tumor. We are reporting this case due to the rarity of GCT and usually these tumors are confined to the suprasellar region since they are arising from the pituitary stalk. GCTs that attain such giant size with cavernous sinus invasion are still rarer. CASE DESCRIPTION: A 38-year-old female who presented with progressive deterioration of vision and on evaluation by magnetic resonance imaging showed a giant pituitary macroadenoma with bilateral cavernous sinus invasion. The patient underwent pterional craniotomy and near-total excision of the lesion was done due to high vascularity and firmness of the tumor. Histopathology examination of the lesion showed spindle to globular cells with granular cytoplasm and was reported as GCT of the pituitary. CONCLUSION: GCTs are WHO grade1 non-neuroendocrine tumors arising from neurohypophysis and infundibulum. Complete excision is usually difficult due to the high vascularity, firm consistency, and local invasion of the tumor to the cavernous sinus and optic apparatus.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...