Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 463
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Neuroradiology ; 63(4): 573-583, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33123752

RESUMO

PURPOSE: Diffusion magnetic resonance imaging (dMRI) studies report altered white matter (WM) development in preterm infants. Neurite orientation dispersion and density imaging (NODDI) metrics provide more realistic estimations of neurite architecture in vivo compared with standard diffusion tensor imaging (DTI) metrics. This study investigated microstructural maturation of WM in preterm neonates scanned between 25 and 45 weeks postmenstrual age (PMA) with normal neurodevelopmental outcomes at 2 years using DTI and NODDI metrics. METHODS: Thirty-one neonates (n = 17 male) with median (range) gestational age (GA) 32+1 weeks (24+2-36+4) underwent 3 T brain MRI at median (range) post menstrual age (PMA) 35+2 weeks (25+3-43+1). WM tracts (cingulum, fornix, corticospinal tract (CST), inferior longitudinal fasciculus (ILF), optic radiations) were delineated using constrained spherical deconvolution and probabilistic tractography in MRtrix3. DTI and NODDI metrics were extracted for the whole tract and cross-sections along each tract to assess regional development. RESULTS: PMA at scan positively correlated with fractional anisotropy (FA) in the CST, fornix and optic radiations and neurite density index (NDI) in the cingulum, CST and fornix and negatively correlated with mean diffusivity (MD) in all tracts. A multilinear regression model demonstrated PMA at scan influenced all diffusion measures, GA and GAxPMA at scan influenced FA, MD and NDI and gender affected NDI. Cross-sectional analyses revealed asynchronous WM maturation within and between WM tracts.). CONCLUSION: We describe normal WM maturation in preterm neonates with normal neurodevelopmental outcomes. NODDI can enhance our understanding of WM maturation compared with standard DTI metrics alone.


Assuntos
Substância Branca , Encéfalo/diagnóstico por imagem , Estudos Transversais , Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Masculino , Substância Branca/diagnóstico por imagem
2.
Eur J Neurol ; 26(8): 1121-1129, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30882969

RESUMO

BACKGROUND AND PURPOSE: Conduction block is a pathognomonic feature of immune-mediated neuropathies. The aim of this study was to advance understanding of pathophysiology and conduction block in chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). METHODS: A multimodal approach was used, incorporating clinical phenotyping, neurophysiology, immunohistochemistry and structural assessments. RESULTS: Of 49 CIDP and 14 MMN patients, 25% and 79% had median nerve forearm block, respectively. Clinical scores were similar in CIDP patients with and without block. CIDP patients with median nerve block demonstrated markedly elevated thresholds and greater threshold changes in threshold electrotonus, whilst those without did not differ from healthy controls in electrotonus parameters. In contrast, MMN patients exhibited marked increases in superexcitability. Nerve size was similar in both CIDP groups at the site of axonal excitability. However, CIDP patients with block demonstrated more frequent paranodal serum binding to teased rat nerve fibres. In keeping with these findings, mathematical modelling of nerve excitability recordings in CIDP patients with block support the role of paranodal dysfunction and enhanced leakage of current between the node and internode. In contrast, changes in MMN probably resulted from a reduction in ion channel density along axons. CONCLUSIONS: The underlying pathologies in CIDP and MMN are distinct. Conduction block in CIDP is associated with paranodal dysfunction which may be antibody-mediated in a subset of patients. In contrast, MMN is characterized by channel dysfunction downstream from the site of block.


Assuntos
Condução Nervosa/fisiologia , Nervos Periféricos/fisiopatologia , Polineuropatias/fisiopatologia , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/fisiopatologia , Adulto , Animais , Axônios/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ratos
3.
Eur J Neurol ; 24(11): 1392-1398, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28799222

RESUMO

BACKGROUND AND PURPOSE: The mechanism of retinal ganglion cell and retinal nerve fiber layer loss in multiple sclerosis (MS) remains unknown. This study aimed to investigate the association between temporal retinal nerve fiber layer (tRNFL) thinning and disease activity in the brain determined by T2 lesions on magnetic resonance imaging (MRI). METHODS: Fifty-five consecutive patients with relapsing-remitting MS and 25 controls were enrolled. All patients underwent annual optical coherence tomography and high-resolution MRI scans for tRNFL thickness and brain lesion volume analysis, respectively. RESULTS: Significant tRNFL thickness reduction was observed over the 3-year follow-up period at a relatively constant rate (1.02 µm/year). Thinning of tRNFL fibers was more prominent in younger patients (P = 0.01). The tRNFL loss was associated with new MRI lesions in the optic radiations (ORs). There was significantly greater tRNFL thinning in patients with new lesional activity in the ORs compared with patients with new lesions outside the ORs (P = 0.009). CONCLUSIONS: This study supports the notion that retrograde transneuronal degeneration caused by OR lesions might play a role in progressive retinal nerve fiber layer loss. In addition, the results of the study also indicate that the disease-related neurodegenerative changes in the retina start much earlier than the clinical diagnosis of MS.


Assuntos
Esclerose Múltipla/complicações , Retina/patologia , Células Ganglionares da Retina/patologia , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Fibras Nervosas/patologia , Retina/diagnóstico por imagem , Tomografia de Coerência Óptica/métodos
4.
Am J Physiol Regul Integr Comp Physiol ; 310(5): R432-9, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26632603

RESUMO

A high-saturated-fat diet (HFD) during pregnancy and lactation leads to metabolic disorders in offspring concomitant with increased adiposity and a proinflammatory phenotype in later life. During the fetal period, the impact of maternal diet on skeletal muscle development is poorly described, despite this tissue exerting a major influence on life-long metabolic health. This study investigated the effect of a maternal HFD on skeletal muscle anabolic, catabolic, and inflammatory signaling in adult rat offspring. Furthermore, the actions of maternal-supplemented conjugated linoleic acid (CLA) on these measures of muscle phenotype were investigated. A purified control diet (CD; 10% kcal fat), a CD supplemented with CLA (CLA; 10% kcal fat, 1% total fat as CLA), a high-fat (HFD; 45% kcal fat from lard), or a HFD supplemented with CLA (HFCLA; 45% kcal fat from lard, 1% total fat as CLA) was fed ad libitum to female Sprague-Dawley rats for 10 days before mating and throughout gestation and lactation. Male offspring received a standard chow diet from weaning, and the gastrocnemius was collected for analysis at day 150. Offspring from HF and HFCLA mothers displayed lower muscular protein content accompanied by elevated monocyte chemotactic protein-1, IL-6, and IL-1ß concentrations. Phosphorylation of NF-κBp65 (Ser(536)) and expression of the catabolic E3 ligase muscle ring finger 1 (MuRF1) were increased in HF offspring, an effect reversed by maternal CLA supplementation. The present study demonstrates the importance of early life interventions to ameliorate the negative effects of poor maternal diet on offspring skeletal muscle development.


Assuntos
Dieta Hiperlipídica , Inflamação/prevenção & controle , Ácidos Linoleicos Conjugados/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Gravidez , Complexo de Endopeptidases do Proteassoma/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Aumento de Peso
5.
J Neurol Neurosurg Psychiatry ; 87(7): 754-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27071647

RESUMO

BACKGROUND: Whole brain volume (WBV) estimates in patients with multiple sclerosis (MS) correlate more robustly with clinical disability than traditional, lesion-based metrics. Numerous algorithms to measure WBV have been developed over the past two decades. We compare Structural Image Evaluation using Normalisation of Atrophy-Cross-sectional (SIENAX) to NeuroQuant and MSmetrix, for assessment of cross-sectional WBV in patients with MS. METHODS: MRIs from 61 patients with relapsing-remitting MS and 2 patients with clinically isolated syndrome were analysed. WBV measurements were calculated using SIENAX, NeuroQuant and MSmetrix. Statistical agreement between the methods was evaluated using linear regression and Bland-Altman plots. Precision and accuracy of WBV measurement was calculated for (1) NeuroQuant versus SIENAX and (2) MSmetrix versus SIENAX. RESULTS: Precision (Pearson's r) of WBV estimation for NeuroQuant and MSmetrix versus SIENAX was 0.983 and 0.992, respectively. Accuracy (Cb) was 0.871 and 0.994, respectively. NeuroQuant and MSmetrix showed a 5.5% and 1.0% volume difference compared with SIENAX, respectively, that was consistent across low and high values. CONCLUSIONS: In the analysed population, NeuroQuant and MSmetrix both quantified cross-sectional WBV with comparable statistical agreement to SIENAX, a well-validated cross-sectional tool that has been used extensively in MS clinical studies.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doenças Desmielinizantes/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Tamanho do Órgão/fisiologia , Adulto , Algoritmos , Atrofia , Avaliação da Deficiência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Eur J Neurol ; 23(4): 729-36, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26782663

RESUMO

BACKGROUND AND PURPOSE: Early relapse outcomes in long-term stable patients switching from interferon ß/glatiramer acetate (IFNß/GA) to oral therapy are unknown. OBJECTIVE: The objective of this study was to compare early relapse and progression in multiple sclerosis (MS) patients switching to oral therapy following a period of stable disease on IFNß/GA, relative to a propensity-matched comparator of patients remaining on IFNß/GA. METHODS: The MSBase cohort study is a global, longitudinal registry for MS. Time to first 6-month relapse in previously stable MS patients switching from platform injectables ('switchers') to oral agents were compared with propensity-matched patients remaining on IFNß/GA ('stayers') using a Cox marginal model. RESULTS: Three-hundred and ninety-six switchers were successfully matched to 396 stayers on a 1:1 basis. There was no difference in the proportion of patients recording at least one relapse in the first 1-6 months by treatment arm (7.3% switchers, 6.6% stayers; P = 0.675). The mean annualized relapse rate (P = 0.493) and the rate of first 6-month relapse by treatment arm (hazard ratio 1.22, 95% confidence interval 0.70, 2.11) were also comparable. There was no difference in the rate of disability progression by treatment arm (hazard ratio 1.43, 95% confidence interval 0.63, 3.26). CONCLUSION: This is the first study to compare early relapse switch probability in the period immediately following switch to oral treatment in a population previously stable on injectable therapy. There was no evidence of disease reactivation within the first 6 months of switching to oral therapy.


Assuntos
Progressão da Doença , Acetato de Glatiramer/administração & dosagem , Fatores Imunológicos/administração & dosagem , Interferon beta/administração & dosagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Sistema de Registros , Administração Oral , Adulto , Feminino , Acetato de Glatiramer/farmacologia , Humanos , Fatores Imunológicos/farmacologia , Interferon beta/farmacologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Recidiva
7.
J Anim Physiol Anim Nutr (Berl) ; 99(3): 483-91, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25271888

RESUMO

Ruminant methane yield (MY) is positively correlated with mean retention time (MRT) of digesta. The hormone triiodothyronine (T3 ), which is negatively correlated with ambient temperature, is known to influence MRT. It was hypothesised that exposing sheep to low ambient temperatures would increase plasma T3 concentration and decrease MRT of digesta within the rumen of sheep, resulting in a reduction of MY. To test this hypothesis, six Merino sheep were exposed to two different ambient temperatures (cold treatment, 9 ± 1 °C; warm control 26 ± 1 °C). The effects on MY, digesta MRT, plasma T3 concentration, CO2 production, DM intake, DM digestibility, change in body weight (BW), rumen volatile fatty acid (VFA) concentrations, estimated microbial protein output, protozoa abundance, wool growth, water intake, urine output and rectal temperature were studied. Cold treatment resulted in a reduction in MY (p < 0.01); digesta MRT in rumen (p < 0.01), hindgut (p = 0.01) and total digestive tract (p < 0.01); protozoa abundance (p < 0.05); and water intake (p < 0.001). Exposure to cold temperature increased plasma T3 concentration (p < 0.05), CO2 production (p = 0.01), total VFA concentrations (p = 0.03) and estimated microbial output from the rumen (p = 0.03). The rate of wool growth increased (p < 0.01) due to cold treatment, but DM intake, DM digestibility and BW change were not affected. The results suggest that exposure of sheep to cold ambient temperatures reduces digesta retention time in the gastrointestinal tract, leading to a reduction in enteric methane yield. Further research is warranted to determine whether T3 could be used as an indirect selection tool for genetic selection of low enteric methane-producing ruminants.


Assuntos
Temperatura Baixa , Motilidade Gastrointestinal/fisiologia , Metano/metabolismo , Ovinos/fisiologia , Tri-Iodotironina/sangue , Ração Animal/análise , Animais , Masculino , Ovinos/sangue , Tri-Iodotironina/metabolismo , Lã/crescimento & desenvolvimento
8.
BJOG ; 121(13): 1710-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24751206

RESUMO

OBJECTIVE: To assess the introduction of Practical Obstetric Multi-professional Training (PROMPT) into maternity units and evaluate effects on organisational culture and perinatal outcomes. DESIGN: A retrospective cohort study. SETTING: Maternity units in eight public hospitals in metropolitan and regional Victoria, Australia. POPULATION: Staff in eight maternity units and a total of 43,408 babies born between July 2008 and December 2011. METHODS: Representatives from eight Victorian hospitals underwent a single day of training (Train the Trainer), to conduct PROMPT. Organisational culture was compared before and after PROMPT. Clinical outcomes were evaluated before, during and after PROMPT. MAIN OUTCOME MEASURES: The number of courses run and the proportion of staff trained were determined. Organisational culture was measured using the Safety Attitude Questionnaire. Clinical measures included Apgar scores at 1 and 5 minutes (Apgar 1 and Apgar 5), cord lactate, blood loss and length of baby's stay in hospital. RESULTS: Seven of the eight hospitals conducted PROMPT. Overall about 50% of staff were trained in each year of the study. Significant increases were found in Safety Attitude Questionnaire scores representing domains of teamwork (Hedges' g 0.27, 95% confidence interval [95% CI] 0.13-0.41), safety (Hedges' g 0.28, 95% CI 0.15-0.42) and perception of management (Hedges' g 0.17, 95% CI 0.04-0.31). There were significant improvements in Apgar 1 (OR 0.84, 95% CI 0.77-0.91), cord lactates (odds ratio 0.92, 95% CI 0.85-0.99) and average length of baby's stay in hospital (Hedges' g 0.03, 95% CI 0.01-0.05) during or after training, but no change in Apgar 5 scores or proportion of cases with high blood loss. CONCLUSION: PROMPT can be introduced using the Train the Trainer model. Improvements in organisational culture and some clinical measures were observed following PROMPT.


Assuntos
Atitude do Pessoal de Saúde , Salas de Parto , Capacitação em Serviço/métodos , Tempo de Internação/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Segurança do Paciente , Assistência Perinatal/normas , Hemorragia Pós-Parto/epidemiologia , Índice de Apgar , Estudos de Coortes , Feminino , Sangue Fetal/química , Humanos , Recém-Nascido , Lactatos/sangue , Cultura Organizacional , Gravidez , Estudos Retrospectivos , Inquéritos e Questionários , Vitória
9.
Intern Med J ; 44(9): 872-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24942202

RESUMO

BACKGROUND: It is unknown whether filling defects in subsegmental arteries on multidetector computed tomography pulmonary angiography correlate with clinically relevant subsegmental pulmonary embolism (PE) on pulmonary angiography. Current guidelines do not differentiate between PE in segmental and subsegmental vessels, and many patients receive at least 3 months anticoagulation. The strategy employed at North Shore Hospital in haemodynamically stable patients with single subsegmental PE is to perform bilateral lower leg compression ultrasound (CUS). Anticoagulation is withheld if CUS is negative; a bilateral CUS is repeated in 7-10 days. AIM: The aim of this retrospective audit was to ensure our current management strategy is safe. METHODS: All diagnoses of single subsegmental PE between June 2005 and June 2013 were included. The primary outcome was the rate of venous thromboembolism (VTE) recurrence within 3 months of single subsegmental PE diagnosis. Secondary outcomes were rates of major/minor bleeding and all-cause mortality. RESULTS: Thirty-two patients were included - 20 were treated with anticoagulation; 12 were managed with observation/serial bilateral lower limb CUS. None of the patients in either group had VTE recurrence by 3 months. No bleeding episodes were observed in the observation group; there was a 10% major bleeding rate (n = 2) in the treatment group. One death occurred in each group, neither of which was attributed to VTE. CONCLUSION: Withholding anticoagulation in patients with single subsegmental PE and negative serial bilateral CUS appears to be a safe and effective management strategy, with a low risk of VTE recurrence.


Assuntos
Anticoagulantes/administração & dosagem , Hemorragia/epidemiologia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/epidemiologia , Tromboembolia Venosa/complicações , Tromboembolia Venosa/tratamento farmacológico , Idoso , Angiografia , Anticoagulantes/efeitos adversos , Auditoria Clínica , Constrição , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Nova Zelândia/epidemiologia , Embolia Pulmonar/etiologia , Embolia Pulmonar/prevenção & controle , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia/métodos , Tromboembolia Venosa/diagnóstico por imagem , Tromboembolia Venosa/epidemiologia
10.
Curr Oncol ; 21(5): 234-50, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25302032

RESUMO

The use of all-trans-retinoic acid (atra) and anthracyclines (with or without cytarabine) in the treatment of acute promyelocytic leukemia (apl) has dramatically changed the management and outcome of the disease over the past few decades. The addition of arsenic trioxide (ato) in the relapsed setting-and, more recently, in reduced-chemotherapy or chemotherapy-free approaches in the first-line setting-continues to improve treatment outcomes by reducing some of the toxicities associated with anthracycline-based approaches. Despite those successes, a high rate of early death from complications of coagulopathy remains the primary cause of treatment failure before treatment begins. In addition to that pressing issue, clarity is needed about the use of ato in the first-line setting and the role of hematopoietic stem-cell transplantation (hsct) in the relapsed setting. The aim for the present consensus was to provide guidance to health care professionals about strategies to reduce the early death rate, information on the indications for hsct and on the use of ato in induction and consolidation in low-to-intermediate-risk and high-risk apl patients.

11.
Mult Scler J Exp Transl Clin ; 10(1): 20552173231226106, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38222025

RESUMO

Background: Siponimod is approved for use in people with secondary progressive multiple sclerosis (pwSPMS). An integrated digital platform, MSGo, was developed for pwSPMS and clinicians to help navigate the multiple steps of the pre-siponimod work-up. Objective: To explore real-world onboarding experiences of siponimod amongst pwSPMS in Australia. Methods: Retrospective, non-interventional, longitudinal, secondary analysis of data extracted from MSGo (20 April 2022). The primary endpoint was the average time for siponimod onboarding; secondary endpoints were adherence and sub-group analyses of variables influencing onboarding. Results: Mixed-cure modelling estimated that 58% of participants (N = 368, females 71%, median age of 59 years) registered in MSGo would ever initiate siponimod. The median time to initiation was 56 days (95% CI [47-59] days). Half of the participants cited 'waiting for vaccination' as the reason for initiation delay. Cox regression analyses found participants with a nominated care partner had faster onboarding (HR 2.1, 95% CI [1.5-3.0]) and were more likely to continue self-reporting daily siponimod dosing than were those without a care partner (HR 2.2, 95% CI [1.3-3.7]). Conclusions: Despite the limitations of self-reported data and the challenges of the COVID-19 pandemic, this study provides insights into siponimod onboarding in Australia and demonstrates the positive impact of care partner support.

12.
Environ Sci Technol ; 47(19): 11241-8, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23941581

RESUMO

The Department of Defense (DoD) is faced with the daunting task of possible remediation of numerous soil-Cr(VI) contaminated sites throughout the continental U.S. The primary risk driver at these sites is hand-to-mouth ingestion of contaminated soil by children. In the following study we investigate the impact of soil geochemical and physical properties on the sorption and bioaccessibility of Cr(VI) in a vast array of soils relevant to neighboring DoD sites. For the 35 soils used in this study, A-horizon soils typically sorbed significantly more Cr(VI) relative to B-horizon soils. Multiple linear regression analysis suggested that Cr(VI) sorption increased with increasing soil total organic C (TOC) and decreasing soil pH. The bioaccessibility of total Cr (CrT) and Cr(VI) on the soils decreased with increasing soil TOC content. As the soil TOC content approached 0.4%, the bioaccessibility of soil bound Cr systematically decreased from approximately 65 to 10%. As the soil TOC content increased from 0.4 to 4%, the bioaccessibility of Cr(VI) and CrT remained relatively constant at approximately 4% and 10%, respectively. X-ray absorption near edge structure (XANES) spectroscopy suggested that Cr(VI) reduction to Cr(III) was prevalent and that the redox transformation of Cr(VI) increased with increasing soil TOC. XANES confirmed that nearly all bioaccessible soil Cr was the Cr(VI) moiety. Multiple linear regression analysis suggested that the bioaccessibility of Cr(VI) and its reduced counterpart Cr(III), decreased with increasing soil TOC and increasing soil pH. This is consistent with the observation that the reduction reaction and formation of Cr(III) increased with increasing soil TOC and that Cr(III) was significantly less bioaccessible relative to Cr(VI). The model was found to adequately describe CrT bioaccessibility in soils from DoD facilities where Cr(VI) contaminated sites were present. The results of this study illustrate the importance of soil properties on Cr(VI) sorption and bioassessability and help define what soil types have the greatest risk associated with Cr(VI) exposure.


Assuntos
Cromo/química , Poluentes do Solo/química , Solo/química , Adsorção , Disponibilidade Biológica , Cromo/metabolismo , Mucosa Gástrica/metabolismo , Humanos , Modelos Teóricos , Poluentes do Solo/metabolismo
13.
Acta Neurol Scand ; 127(5): 301-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22970985

RESUMO

BACKGROUND: Patients with multiple sclerosis (MS) are more frequently born in spring when compared to autumn. Fluctuation of UV-light has been hypothesized to drive this phenomenon. AIM: To assess the correlation between fluctuation of sunlight and birth season in persons with MS. METHODS: For this record-linkage study, we collected from the international MSBase and the Italian MS iMed-web databases the dates of birth of 11,415 patients with MS from 36 centres from 15 countries worldwide and compared these to dates of live-births from national registries. From all participating sites, we collected data on UV-light fluctuation and assessed its correlation with seasonal fluctuation in MS births. RESULTS: Compared with the reference cohort, an increased proportion of persons with MS were born in spring and a decreased proportion in autumn (odds ratio (OR) to be born in spring versus autumn = 1.158, χ² = 36.347, P < 0.001). There was no significantly increased fluctuation of MS births with increased quartile of ambient UV-light fluctuation (Ptrend = 0.086). CONCLUSION: Seasonal fluctuation of MS births as found in this worldwide cohort of patients with MS did not correlate with variation in seasonal fluctuation of UV-light. Most likely, it results from a complex interplay between fluctuation of sunlight, behavioural factors, other environmental factors and (epi)genetic factors.


Assuntos
Esclerose Múltipla/epidemiologia , Efeitos Tardios da Exposição Pré-Natal , Estações do Ano , Luz Solar , Raios Ultravioleta , Bases de Dados Factuais , Feminino , Saúde Global , Humanos , Masculino , Gravidez , Sistema de Registros , Fatores de Risco
14.
Nat Genet ; 2(4): 283-7, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1303280

RESUMO

Novel approaches to the structural and functional analysis of mammalian chromosomes would be possible if the gross structure of the chromosomes in living cells could be engineered. Controlled modifications can be engineered by conventional targeting techniques based on homologous recombination. Large but uncontrolled modifications can be made by the integration of cloned human telomeric DNA. We describe here the combined use of gene targeting and telomere-mediated chromosome breakage to generate a defined truncation of a human chromosome. Telomeric DNA was targeted to the 6-16 gene on the short arm of chromosome 1 in a human cell line. Molecular and cytogenetic analyses showed that, of eight targeted clones that were isolated, one clone had the predicted truncation of chromosome 1.


Assuntos
Cromossomos Humanos Par 1/ultraestrutura , DNA/genética , Telômero/ultraestrutura , Linhagem Celular , Deleção Cromossômica , Clonagem Molecular , Engenharia Genética , Técnicas Genéticas , Humanos , Recombinação Genética
15.
Sci Data ; 10(1): 198, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37037860

RESUMO

Honey bee, Apis mellifera, drones are typically haploid, developing from an unfertilized egg, inheriting only their queen's alleles and none from the many drones she mated with. Thus the ordered combination or 'phase' of alleles is known, making drones a valuable haplotype resource. We collated whole-genome sequence data for 1,407 drones, including 45 newly sequenced Scottish drones, collectively representing 19 countries, 8 subspecies and various hybrids. Following alignment to Amel_HAv3.1, variant calling and quality filtering, we retained 17.4 M high quality variants across 1,328 samples with a genotyping rate of 98.7%. We demonstrate the utility of this haplotype resource, AmelHap, for genotype imputation, returning >95% concordance when up to 61% of data is missing in haploids and up to 12% of data is missing in diploids. AmelHap will serve as a useful resource for the community for imputation from low-depth sequencing or SNP chip data, accurate phasing of diploids for association studies, and as a comprehensive reference panel for population genetic and evolutionary analyses.


Assuntos
Abelhas , Genoma de Inseto , Animais , Feminino , Sequência de Bases , Abelhas/genética , Evolução Biológica , Genótipo , Projeto HapMap
16.
Mult Scler ; 18(1): 108-12, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21868485

RESUMO

Auto-antibody mediated astrocyte injury is implicated as a primary event in neuromyelitis optica (NMO) by biomarker, post-mortem and experimental studies that differentiate the condition from multiple sclerosis. We describe the clinical, radiological and neuropathological features of a severe cerebral attack in a natalizumab-treated patient with relapsing myelitis and serum aquaporin-4 antibodies. Our findings support autopsy evidence that abrupt astrocyte destruction precedes demyelination in NMO, and emphasize the importance of serological testing in patients with limited disease. Adherence to current NMO diagnostic criteria may delay treatment, or lead to inappropriate therapy with beta-interferon or natalizumab.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Astrócitos/patologia , Neuromielite Óptica/sangue , Neuromielite Óptica/patologia , Aquaporina 4/imunologia , Autoanticorpos/sangue , Autoanticorpos/imunologia , Autoantígenos/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Natalizumab , Neuromielite Óptica/tratamento farmacológico
17.
Mult Scler ; 18(7): 974-82, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22185806

RESUMO

BACKGROUND: With the advent of MRI scanning, the value of lumbar puncture to assess oligoclonal band (OCB) status-for the diagnosis of multiple sclerosis (MS) is increasingly uncertain. One major issue is that the reported frequency of cerebrospinal fluid (CSF)-restricted oligoclonal banding for the diagnosis of MS varies considerably in different studies. In addition, the relationship between OCB positivity and disease outcome remains uncertain, as reported studies are generally too small to assess comparative disability outcomes with sufficient power. METHODS: In order to further investigate variation of OCB positivity in patients with MS, we utilized MSBase, a longitudinal, Web-based collaborative MS outcomes registry following clinical cohorts in several continents and latitudes. We also assessed whether OCB positivity affects long-term disability outcome. RESULTS: A total of 13,242 patient records were obtained from 37 MS specialist centres in 19 different countries. OCB status was documented in 4481 (34%) patients and 80% of these were OCB positive. The presence of OCB was associated with degree of latitude (p = 0.02). Furthermore, the outcome of patients negative for CSF-specific OCB was significantly better in comparison to the OCB positive patients, as assessed by Expanded Disability Status Scale change (p < 0.001). CONCLUSIONS: The results of this study indicate that latitude could explain some of the inconsistencies in OCB status reported in different populations. The study confirms that OCB positivity in MS is associated with a worse long-term prognosis.


Assuntos
Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/epidemiologia , Bandas Oligoclonais/líquido cefalorraquidiano , Adulto , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Sistema de Registros
18.
Stud Health Technol Inform ; 164: 82-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21335692

RESUMO

BACKGROUND: New data management models are emerging in multi-center clinical studies. We evaluated the incremental costs associated with decentralized vs. centralized models. METHODS: We developed clinical research network economic models to evaluate three data management models: centralized, decentralized with local software, and decentralized with shared database. Descriptive information from three clinical research studies served as inputs for these models. MAIN OUTCOME MEASURES: The primary outcome was total data management costs. Secondary outcomes included: data management costs for sites, local data centers, and central coordinating centers. RESULTS: Both decentralized models were more costly than the centralized model for each clinical research study: the decentralized with local software model was the most expensive. Decreasing the number of local data centers and case book pages reduced cost differentials between models. CONCLUSION: Decentralized vs. centralized data management in multi-center clinical research studies is associated with increases in data management costs.


Assuntos
Sistemas de Informação Hospitalar/economia , Sistemas de Informação Hospitalar/organização & administração , Gestão da Informação/organização & administração , Modelos Organizacionais , Custos e Análise de Custo/métodos
19.
Oral Dis ; 16(7): 586-91, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20846148

RESUMO

Oral Diseases (2010) 16, 586-591 High quality clinical research is necessary to improve oral health and translate research findings to the practice of dentistry. This has led many academic institutions to consider establishing a formal clinical research center. This is not a trivial undertaking and requires that the center have an appropriate physical infrastructure, trained investigators with recognized expertise in the planning and conduct of high quality clinical research, and very importantly, a financial plan to assure its long-term sustainability. The purpose of this paper is to provide some guidance and practical advice with respect to factors that should be considered in developing and maintaining a successful oral disease clinical research center.


Assuntos
Academias e Institutos/organização & administração , Pesquisa em Odontologia/organização & administração , Academias e Institutos/economia , Pesquisa em Odontologia/economia , Arquitetura de Instituições de Saúde , Guias como Assunto , Experimentação Humana , Humanos , Seleção de Pacientes , Competência Profissional , Projetos de Pesquisa , Pesquisadores/educação , Pesquisadores/normas , Apoio à Pesquisa como Assunto
20.
Ethn Dis ; 20(1 Suppl 1): S1-150-4, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20521405

RESUMO

BACKGROUND: RCMI Translational Research Network (RTRN) is the first academic-based national network to address the problem of health disparities by integrating minority medical schools in a collaborative effort. While there was a great interest in forming the research network, limited systematic effort has been made in understanding members' existing capacity and future demand. OBJECTIVE: The aim of this study was to report the results of the RTRN Statistical Capacity Assessment and discuss the importance of an initial capacity assessment in building the biostatistical capacity of a research network in its early stage. METHODS: The assessment was based on survey responses submitted by program directors/managers from 12 of the 18 RTRN institutions. In this assessment the capacity is defined as the statistical tools and human resources which are required for effective and efficient performance. RESULTS: A total of 52 biostatisticians (mean of 4.5 per site) were working for 12 RTRN institutions; 84% were fulltime employees, and 53% held a doctoral degree. On average, they had about 13 years of job experience. SAS, SPSS and STATA were the most frequently used and were selected as their major statistical software. A wide inter-institutional variability was found in number of biostatisticians (ranged from 1 to 8), mean years of experience in their position (4.5-20 years) and in major software (5-20), and the number of statistical software in use (1-11). CONCLUSION: The initial capacity assessment provided valuable information on members' background and the network's research capacity which will be used as the basic data in developing programs to build research capacity. Therefore, it is important to include the initial capacity survey and on-going evaluation of network activities when making business plans of research networks intended to reduce health disparities.


Assuntos
Disparidades nos Níveis de Saúde , Avaliação das Necessidades , Pesquisa Translacional Biomédica/organização & administração , Humanos , Software , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA