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1.
J Neurol Sci ; 418: 117162, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-33017712

RESUMO

OBJECTIVE: To investigate the use of the King-Devick (K-D) test for sideline assessment of concussive injuries in a New Zealand amateur women's rugby union team. DESIGN: Prospective cohort observational. METHODS: All players were K-D tested during pre-season using a tablet (iPad; Apple Inc., Cupertino, CA). Differences in K-D scores and test-retest reliability were calculated for baseline test scores, baseline, and post-injury (concussion) sideline assessment and baseline and post-season testing scores for tests by year and as a combined score. RESULTS: One training-related (0.3 per 1000 training-hrs) and nine match-related (16.1 per 1000 match-hrs) concussions were recorded. The K-D post-injury (concussion) sideline test score were significantly slower than established baseline (-4.4 [-5.8 to -3.4] s; χ2(1) = 42.2; p < 0.0001; t(9) = -4.0; p = 0.0029; d = -0.8). There was good-to-excellent reliability of the K-D test for baseline (ICC: 0.84 to 0.89), post-injury (concussion) sideline assessment (ICC: 0.82 to 0.97) and post-season evaluation (ICC: 0.79 to 0.83). DISCUSSION: By utilising the baseline to post-injury (concussion) assessment comparisons, any player with a post-injury (concussion) assessment slowing of their K-D test time, regardless of whether the player has, or has not had a witnessed insult, should be withheld from any further participation until they are evaluated by a medical professional trained in the management of concussion. CONCLUSION: This study has provided additional evidence to support the use of the K-D test as a frontline method of assessing concussion with good to excellent reliability of the test for baseline, side-line assessment and post-season evaluation.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Futebol Americano , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/epidemiologia , Concussão Encefálica/diagnóstico , Concussão Encefálica/epidemiologia , Feminino , Humanos , Testes Neuropsicológicos , Nova Zelândia/epidemiologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Estações do Ano
2.
Chem Res Toxicol ; 12(11): 1066-76, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10563832

RESUMO

Ochratoxin A (OTA, 1) is a fungal toxin that facilitates single-strand DNA cleavage, DNA adduction, and lipid peroxidation when metabolically activated. To model the enzymatic activation of OTA, we have employed the water-soluble iron(III) meso-tetrakis(4-sulfonatophenyl)porphyrin (FeTPPS) oxidation system. In its presence, OTA has been found to facilitate single-strand cleavage of supercoiled plasmid DNA through production of reactive oxygen species (ROS) (i.e., the hydroxyl radical, HO(*)). The reaction of OTA with the FeTPPS oxidation system also generated three hydroxylated products (chlorine atom still attached), which was taken as evidence for production of the known hydroxylated metabolites (2-4) of OTA. This result suggested that the FeTPPS system served as a reasonable model for the enzymatic activation of OTA. When the reaction of OTA with FeTPPS was carried out in the presence of excess hydrogen peroxide (H(2)O(2)) and sodium ascorbate, a hydroquinone species (OTHQ, 5) was detected in which an OH group has replaced the chlorine atom of OTA. The production of OTHQ (5) was dependent on the presence of the reducing agent, sodium ascorbate, which suggested that the oxidation catalyst furnished the quinone derivative OTQ (6) that was subsequently reduced to OTHQ (5) by ascorbate. Utilizing a synthetic sample of OTHQ (5), the hydroquinone was found to undergo autoxidation with a t(1/2) of 11.1 h at pH 7.4, and to possess a pK(a) value of 8.03 for the phenolic oxygen ortho to the carbonyl groups. Our findings imply that the hydroquinone (OTHQ) and quinone (OTQ) metabolites of OTA have the ability to cause alkylation/redox damage and have allowed us to propose a viable pathway for oxidative damage by OTA.


Assuntos
Dano ao DNA , Ferro/química , Micotoxinas/química , Ocratoxinas/química , Porfirinas/química , Ácido Ascórbico/química , Cromatografia Líquida de Alta Pressão , DNA Super-Helicoidal/química , Concentração de Íons de Hidrogênio , Peroxidação de Lipídeos , Espectrometria de Massas , Modelos Biológicos , Oxirredução , Plasmídeos/química , Espectrofotometria Ultravioleta
3.
J Chromatogr B Biomed Sci Appl ; 755(1-2): 165-72, 2001 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-11393701

RESUMO

3'-Azido-2',3'-dideoxyuridine (AZDU, Azddu, CS-87) is a nucleoside analog of 3'-azido-3'-deoxythymidine (zidovudine, AZT) that has been shown to inhibit human immunodeficiency virus (HIV-1). AZDU is a potential candidate for treatment of pregnant mothers to prevent prenatal transmission of HIV/AIDS to their unborn children. A rapid and efficient high-performance liquid chromatography (HPLC) method for the determination of AZDU concentrations in rat maternal plasma, amniotic fluid, placental and fetal tissue samples has been developed and validated. Tissue samples were homogenized in distilled water, protein precipitated and extracted using a C-18 solid-phase extraction (SPE) method prior to analysis. Plasma and amniotic fluid samples were protein precipitated with 2 M perchloric acid prior to analysis. Baseline resolution was achieved using a 4.5% acetonitrile in 40 mM sodium acetate (pH 7) buffer mobile phase for amniotic fluid, placenta and fetus samples and with a 5.5% acetonitrile in buffer solution for plasma at flow-rates of 2.0 ml/min. The HPLC system consists of a Hypersil ODS column (150x4.6 mm) with a Nova-Pak C-18 guard column with detection at 263 nm. The method yields retention times of 6.2 and 12.2 min for AZDU and AZT in plasma and 8.3 and 17.6 min for AZDU and AZT in amniotic fluid, fetal and placental tissues. Limits of detection ranged from 0.01 to 0.075 microg/ml. Recoveries ranged from 81 to 96% for AZDU and from 82 to 96% for AZT in the different matrices. Intra-day (n=6) and inter-day (n=9) precision (% RSD) and accuracy (% Error) ranged from 1.48 to 6.25% and from 0.50 to 10.07%, respectively.


Assuntos
Líquido Amniótico/química , Antivirais/sangue , Feto/química , Placenta/química , Zidovudina/análogos & derivados , Zidovudina/sangue , Animais , Antivirais/uso terapêutico , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Estrutura Molecular , Gravidez , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes
4.
Mol Ther ; 1(1): 49-55, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10933911

RESUMO

Endowing T lymphocytes with novel functional attributes by genetic modification is under development for a broad range of clinical cellular immunotherapy applications. To circumvent many of the limitations associated with viral vector systems, a plasmid-based electroporation system that reliably generates G418-resistant primary human T lymphocyte clones was developed. TCR alpha/beta+ CD4+CD8-, and CD4-CD8+ T lymphocyte clones can be routinely isolated from OKT3-stimulated peripheral blood mononuclear cells electroporated with linear plasmid DNA in a limiting dilution drug selection format. Fluorescence in situ hybridization (FISH) studies performed on T cell metaphase spreads using a probe specific for plasmid sequence demonstrated a single FISH signal doublet that varied in chromosomal location from clone to clone. Southern blot analysis using a Neo-specific probe verified chromosomal integration of plasmid vector at a single site. Band intensity quantitation of blots developed with a zeta-specific probe capable of annealing to both endogenous TCR-zeta and the introduced chimeric zeta sequence demonstrated that integrated plasmid was present at a single copy number. Expression levels of the CD20-specific chimeric immunoreceptor construct from a CMV immediate/early promoter present in the plasmid vector varied widely from clone to clone but remained stable during ex vivo expansion to cell numbers in excess of 10(10). This T lymphocyte genetic modification strategy is currently being piloted in a FDA-sanctioned adoptive therapy trial for recurrent lymphoma.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Terapia Genética/métodos , Imunoterapia/métodos , Plasmídeos/genética , Linhagem Celular , Células Clonais , Eletroporação , Vetores Genéticos , Humanos , Hibridização in Situ Fluorescente , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia
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