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1.
J Psychiatr Res ; 175: 50-59, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38704981

RESUMO

Major depressive disorder (MDD) stands as a significant cause of disability globally. Cannabidiolic Acid-Methyl Ester (CBDA-ME) (EPM-301, HU-580), a derivative of Cannabidiol, demonstrates immediate antidepressant-like effects, yet it has undergone only minimal evaluation in psychopharmacology. Our goal was to investigate the behavioral and potential molecular mechanisms associated with the chronic oral administration of this compound in the Wistar Kyoto (WKY) genetic model of treatment-resistant depression. Male WKY rats were subjected to behavioral assessments before and after receiving chronic (14-day) oral doses of CBDA-ME (0.5 mg/kg), 15 mg/kg of imipramine or vehicle. At the end of the study, plasma corticosterone levels and mRNA expression of various genes in the medial Prefrontal Cortex and Hippocampus were measured. Behavioral outcomes from CBDA-ME treatment indicated an antidepressant-like effect similar to imipramine, as oral ingestion reduced immobility and increased swimming duration in the Forced Swim Test. Neither treatment influenced locomotion in the Open Field Test nor preference in the Saccharin Preference Test. The behavioral impact in WKY rats coincided with reduced corticosterone serum levels, upregulated mRNA expression of Cannabinoid receptor 1, Fatty Acid Amide Hydrolase, and Corticotropin-Releasing Hormone Receptor 1, alongside downregulation of the Serotonin Transporter in the hippocampus. Additionally, there was an upregulation of CB1 mRNA expression and downregulation of Brain-Derived Neurotrophic Factor in the mPFC. These findings contribute to our limited understanding of the antidepressant effects of CBDA-ME and shed light on its potential psychopharmacological mechanisms. This discovery opens up possibilities for utilizing cannabinoids in the treatment of major depressive disorder and related conditions.

2.
Ann R Coll Surg Engl ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661438

RESUMO

INTRODUCTION: Medullary thyroid carcinoma (MTC) is a rare thyroid cancer arising from the calcitonin-secreting parafollicular cells. Previous studies suggested a preoperative calcitonin level >200ng/l is an indication for prophylactic lateral neck dissection (LND) to remove micrometastases and improve survival outcomes. METHODS: This retrospective single-centre study assessed the efficacy of preoperative calcitonin levels as a marker for determining need for prophylactic LND in MTC. Data were obtained on demographics, preoperative calcitonin levels, size and laterality of index tumour, type of neck dissection (central neck dissection (CND), LND), nodes removed, levels with involved nodes, number of nodes histologically involved, mortality, adjuvant therapy and locoregional recurrence. RESULTS: A total of 33 patients were identified from St George's University Hospitals NHS Foundation Trust between 1 January 2001 and 19 August 2021; 8 were excluded for data quality issues. Of the 18 classified with a high preoperative calcitonin level (>200ng/l), 10 (56%) had a LND and 8 (44%) had a CND. In the low-calcitonin group, three (43%) patients had a CND only and four (57%) had a LND. There was no difference in absolute or disease-free survival between the low and high groups (p=0.960, p=0.817), or between those who had a CND and LND in the high-calcitonin group (p=0.607, hazard ratio (HR) 0.55; p=0.129, HR 8.78). CONCLUSION: There was no statistically significant difference in outcomes between high and low calcitonin groups. A selective approach to performing LND in MTC patients based on clinical and imaging findings suggesting disease presence in the lateral neck should be explored further.

4.
Ann R Coll Surg Engl ; 102(7): e161-e166, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32347741

RESUMO

Head and neck tumour thrombus is a rare pathology and at present there are no reported cases of tumour thrombus secondary to acinic cell carcinoma of the parotid gland. We report a case of an 81-year-old man with an acinic cell carcinoma of the left parotid and an intravenous tumour thrombus extending from the retromandibular vein into the internal jugular vein. This case also highlights the importance of radiological imaging in the management of tumour thrombus.


Assuntos
Carcinoma de Células Acinares/complicações , Glândula Parótida/diagnóstico por imagem , Neoplasias Parotídeas/complicações , Trombose Venosa/etiologia , Idoso de 80 Anos ou mais , Carcinoma de Células Acinares/diagnóstico , Humanos , Veias Jugulares/diagnóstico por imagem , Masculino , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Neoplasias Parotídeas/diagnóstico , Flebografia , Doenças Raras , Tomografia Computadorizada por Raios X , Trombose Venosa/diagnóstico
5.
Dalton Trans ; 49(17): 5416-5419, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32250374

RESUMO

An easy, direct and room temperature silicon-carbon bond activation is reported. The reaction of [RhCl(coe)2]2 with the silane Si(Me)2(o-C6H4SMe)2 in the presence of an halide extractor provokes a Si-CH3 bond cleavage yielding a cationic silyl-methyl-Rh(iii). In contrast, if the reaction is performed using the Rh(i) bis-alkene dimers, [RhCl(cod)]2 or [RhCl(nbd)]2, the Si-CH3 bond activation does not occur.

6.
Behav Brain Res ; 351: 1-3, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860002

RESUMO

BACKGROUND AND PURPOSE: Cannabidiolic acid methyl ester (HU-580) was recently shown to reduce stress-induced anxiety-like behavior in rats. The aim of this study was to examine the antidepressant effect of HU-580 in two different rat models of depression. EXPERIMENTAL APPROACH: Using the forced swim test (FST), we evaluated the effect of HU-580 in 43 Wistar-Kyoto (WKY) and 23 Flinders Sensitive Line (FSL) adult male rats. KEY RESULTS: 1 mg/kg HU-580 reduced immobility and increased swimming in WKY rats, compared to vehicle-treated controls (p < 0.05). This dose exerted similar effects in FSL rats (p < 0.05). CONCLUSION AND IMPLICATIONS: This is the first report of antidepressant efficacy of HU-580. These findings expand the very limited existent results, suggesting that HU-580 is a potent anxiolytic agent. Taken together with its chemical stability, HU-580 emerges as a candidate for a future antidepressant medication.


Assuntos
Antidepressivos/farmacologia , Canabinoides/farmacologia , Transtorno Depressivo/tratamento farmacológico , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Atividade Motora/efeitos dos fármacos , Ratos Endogâmicos WKY , Especificidade da Espécie
7.
Eur Radiol ; 28(3): 1118-1131, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28956113

RESUMO

For body imaging, diffusion-weighted MRI may be used for tumour detection, staging, prognostic information, assessing response and follow-up. Disease detection and staging involve qualitative, subjective assessment of images, whereas for prognosis, progression or response, quantitative evaluation of the apparent diffusion coefficient (ADC) is required. Validation and qualification of ADC in multicentre trials involves examination of i) technical performance to determine biomarker bias and reproducibility and ii) biological performance to interrogate a specific aspect of biology or to forecast outcome. Unfortunately, the variety of acquisition and analysis methodologies employed at different centres make ADC values non-comparable between them. This invalidates implementation in multicentre trials and limits utility of ADC as a biomarker. This article reviews the factors contributing to ADC variability in terms of data acquisition and analysis. Hardware and software considerations are discussed when implementing standardised protocols across multi-vendor platforms together with methods for quality assurance and quality control. Processes of data collection, archiving, curation, analysis, central reading and handling incidental findings are considered in the conduct of multicentre trials. Data protection and good clinical practice are essential prerequisites. Developing international consensus of procedures is critical to successful validation if ADC is to become a useful biomarker in oncology. KEY POINTS: • Standardised acquisition/analysis allows quantification of imaging biomarkers in multicentre trials. • Establishing "precision" of the measurement in the multicentre context is essential. • A repository with traceable data of known provenance promotes further research.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/normas , Progressão da Doença , Voluntários Saudáveis , Humanos , Estudos Multicêntricos como Assunto , Prognóstico , Estudos Prospectivos , Garantia da Qualidade dos Cuidados de Saúde , Reprodutibilidade dos Testes , Software
8.
Mol Psychiatry ; 23(6): 1432-1445, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29257131

RESUMO

Stress-related psychopathology is highly prevalent among elderly individuals and is associated with detrimental effects on mood, appetite and cognition. Conversely, under certain circumstances repeated mild-to-moderate stressors have been shown to enhance cognitive performance in rodents and exert stress-inoculating effects in humans. As most stress-related favorable outcomes have been reported in adolescence and young-adulthood, this apparent disparity could result from fundamental differences in how aging organisms respond to stress. Furthermore, given prominent age-related alterations in sex hormones, the effect of chronic stress in aging females remains a highly relevant yet little studied issue. In the present study, female C57BL/6 mice aged 3 (young-adult) and 20-23 (old) months were subjected to 8 weeks of chronic unpredictable stress (CUS). Behavioral outcomes were measured during the last 3 weeks of the CUS protocol, followed by brain dissection for histological and molecular end points. We found that in young-adult female mice, CUS resulted in decreased anxiety-like behavior and enhanced cognitive performance, whereas in old female mice it led to weight loss, dysregulated locomotion and memory impairment. These phenotypes were paralleled by differential changes in the expression of hypothalamic insulin and melanocortin-4 receptors and were consistent with an age-dependent reduction in the dynamic range of stress-related changes in the hippocampal transcriptome. Supported by an integrated microRNA (miRNA)-mRNA expression analysis, the present study proposes that, when confronted with ongoing stress, neuroprotective mechanisms involving the upregulation of neurogenesis, Wnt signaling and miR-375 can be harnessed more effectively during young-adulthood. Conversely, we suggest that aging alters the pattern of immune activation elicited by stress. Ultimately, interventions that modulate these processes could reduce the burden of stress-related psychopathology in late life.


Assuntos
Ansiedade/metabolismo , Cognição/fisiologia , Estresse Psicológico/metabolismo , Fatores Etários , Animais , Comportamento Animal , Encéfalo/metabolismo , Feminino , Hipocampo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neurobiologia , Neurogênese/fisiologia
9.
West Indian med. j ; 67(spe): 382-386, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-1045882

RESUMO

ABSTRACT The Doctor of Medicine (DM) in Paediatrics Programme began in 1972 in Jamaica and was the first four-year clinical residency programme to be offered at The University of the West Indies (UWI). The DM Paediatrics programme trains residents for four-years and equips them after completion to practice as consultant paediatricians. Over the forty-five years of offering this programme, 237 students have been enrolled and 159 students have successfully completed the course. Over ninety per cent of the graduates are Caribbean nationals. Graduates from the DM Paediatrics programme at Mona are currently serving in Jamaica and other Caribbean countries, the United States of America (USA), Canada, Australia and the United Kingdom. Approximately, 24% have pursued subspecialty training and 60% work in a hospital-based setting while 30% work in private practice and 27% in academia and research. There are some of these that combine hospital ward work with academia and research. The DM (Paediatrics) Programme at the UWI, Mona, has achieved its mandate of providing paediatricians for Jamaica and the Caribbean and is committed to continue to train paediatricians to meet existing paediatric healthcare needs in Jamaica and the Caribbean.


RESUMEN El Programa de Doctor en Medicina (DM) en Pediatría comenzó en 1972 en Jamaica y fue el primer programa de residencia clínica de cuatro años que se ofreció en la Universidad de West Indies (UWI). El programa DM de Pediatría entrena a los residentes durante cuatro años y los faculta después de su terminación para practicar como pediatras consultores. En los 45 años de este programa, 237 estudiantes han sido matriculados y 159 estudiantes han completado con éxito el curso. Más del 90 por ciento de los graduados son nacionales del Caribe. Los egresados del programa DM de Pediatría de Mona prestan actualmente sus servicios en Jamaica y otros países del Caribe, los Estados Unidos de América (EE. UU.), Canadá, Australia y el Reino Unido. Aproximadamente, el 24% han continuado su formación en subespecialidades; el 60% trabaja en el medio hospitalario, mientras que el 30% trabaja en la práctica privada; y el 27% en la academia y la investigación. Algunos de ellos combinan el trabajo en las salas de hospitales con la academia y la investigación. El programa DM (Pediatría) de UWI, Mona, ha logrado su mandato de proveer pediatras para Jamaica y el Caribe, y se compromete a seguir capacitando a pediatras para que satisfagan las necesidades de salud pediátrica existentes en Jamaica y el Caribe.


Assuntos
Humanos , Masculino , Feminino , Pediatria/educação , Educação Médica Continuada/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Internato e Residência/estatística & dados numéricos , Estudantes , Pediatras/educação , Jamaica
11.
BJOG ; 124(11): 1664-1670, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28334503

RESUMO

OBJECTIVE: To evaluate whether exposure to clomiphene citrate (CC) for ovulation induction is associated with major malformations overall or with specific fetal anomalies. DESIGN: We conducted a population-based retrospective cohort study. Exposure was defined as CC dispension from 2 months before conception through the first month of pregnancy. SETTINGS: Four databases were combined: medication, birth, hospitalization, and terminations of pregnancy. POPULATION: The study included all women in southern Israel who gave birth or underwent termination of pregnancy at Soroka Medical Center, from 1998 to 2009. METHODS: The rates of major malformations overall and six different subcategories of anomalies were evaluated. The crude odds ratio (OR) was calculated with a 95% confidence interval (95% CI). Subsequently the adjusted odds ratio (aOR) was calculated using multiple logistic regression models controlling for maternal age, pre-pregnancy diabetes, parity, ethnicity, the calendar year in which the birth/termination of pregnancy took place, smoking, and the use of gonadotropins and progesterone. MAIN OUTCOME MEASURES: Major malformations overall and specific fetal malformations by organ systems. RESULTS: Of 114 961 pregnant women, 1872 were exposed to CC. No association was detected between exposure to CC and rates of major malformations overall (aOR 1.08, 95% CI 0.88-1.32) or rates of subcategories of malformations. Exposure was not associated with anencephaly (aOR 2.27, 95% CI 0.44-11.71) or oesophageal atresia (aOR 3.681, 95% CI, 0.65-20.76). CONCLUSIONS: In this large population-based retrospective cohort study, exposure to CC was not associated with an increased risk of either rates of major malformations overall or rates of specific malformations. TWEETABLE ABSTRACT: An observational study: no increased risk for fetal malformations following exposure to clomiphene citrate.


Assuntos
Anormalidades Induzidas por Medicamentos/epidemiologia , Clomifeno/efeitos adversos , Anormalidades Congênitas/epidemiologia , Fármacos para a Fertilidade Feminina/efeitos adversos , Infertilidade Feminina/tratamento farmacológico , Adolescente , Adulto , Clomifeno/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Incidência , Recém-Nascido , Infertilidade Feminina/epidemiologia , Israel/epidemiologia , Gravidez , Resultado da Gravidez , Cuidado Pré-Natal/métodos , Estudos Retrospectivos , Adulto Jovem
12.
Eur J Cancer ; 59: 65-78, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27016624

RESUMO

Therapeutic options in locally advanced non-small cell lung cancer (NSCLC) have expanded in the past decade to include a palate of targeted interventions such as high dose targeted thermal ablations, radiotherapy and growing platform of antibody and small molecule therapies and immunotherapies. Although these therapies have varied mechanisms of action, they often induce changes in tumour architecture and microenvironment such that response is not always accompanied by early reduction in tumour mass, and evaluation by criteria other than size is needed to report more effectively on response. Functional imaging techniques, which probe the tumour and its microenvironment through novel positron emission tomography and magnetic resonance imaging techniques, offer more detailed insights into and quantitation of tumour response than is available on anatomical imaging alone. Use of these biomarkers, or other rational combinations as readouts of pathological response in NSCLC have potential to provide more accurate predictors of treatment outcomes. In this article, the robustness of the more commonly available positron emission tomography and magnetic resonance imaging biomarker indices is examined and the evidence for their application in NSCLC is reviewed.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Ablação por Cateter/métodos , Hipóxia Celular , Proliferação de Células , Previsões , Humanos , Imunoterapia/métodos , Neoplasias Pulmonares/irrigação sanguínea , Imageamento por Ressonância Magnética , Terapia de Alvo Molecular/métodos , Imagem Multimodal , Variações Dependentes do Observador , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Resultado do Tratamento , Microambiente Tumoral
13.
Rev Sci Instrum ; 86(7): 073508, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26233384

RESUMO

At ASDEX Upgrade (AUG), a new compact solid-state detector has been installed to measure the energy spectrum of fast neutrals based on the principle described by Shinohara et al. [Rev. Sci. Instrum. 75, 3640 (2004)]. The diagnostic relies on the usual charge exchange of supra-thermal fast-ions with neutrals in the plasma. Therefore, the measured energy spectra directly correspond to those of confined fast-ions with a pitch angle defined by the line of sight of the detector. Experiments in AUG showed the good signal to noise characteristics of the detector. It is energy calibrated and can measure energies of 40-200 keV with count rates of up to 140 kcps. The detector has an active view on one of the heating beams. The heating beam increases the neutral density locally; thereby, information about the central fast-ion velocity distribution is obtained. The measured fluxes are modeled with a newly developed module for the 3D Monte Carlo code F90FIDASIM [Geiger et al., Plasma Phys. Controlled Fusion 53, 65010 (2011)]. The modeling allows to distinguish between the active (beam) and passive contributions to the signal. Thereby, the birth profile of the measured fast neutrals can be reconstructed. This model reproduces the measured energy spectra with good accuracy when the passive contribution is taken into account.

14.
Cardiovasc Intervent Radiol ; 38(3): 747-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25547081

RESUMO

We report the first case of intervention for a proximal type 1 endoleak following Nellix endovascular aneurysm sealing repair of an aortic aneurysm. This was complicated by migration of Onyx into one of the Nellix graft limbs causing significant stenosis. Subsequent placement of a covered stent to affix the Onyx between the stent and the wall of the Nellix endograft successfully restored stent patency.


Assuntos
Aneurisma Aórtico/cirurgia , Embolização Terapêutica , Endoleak/terapia , Procedimentos Endovasculares , Polivinil/uso terapêutico , Complicações Pós-Operatórias/terapia , Idoso de 80 Anos ou mais , Aortografia , Endoleak/diagnóstico por imagem , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico por imagem , Stents , Tomografia Computadorizada por Raios X
15.
Clin Radiol ; 69(1): 82-95, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24047953

RESUMO

Single photon emission computed tomography combined with computed tomography (SPECT-CT), which combines functional and anatomical imaging, provides superior spatial localization to plain radiography and is more tolerant to metallic artefacts than conventional imaging such as magnetic resonance imaging (MRI). It is increasingly used in musculoskeletal imaging to enable accurate anatomical localization of increased tracer uptake, and is particularly useful in assessing metal prosthesis and the surrounding bone following total hip arthroplasty (THA). In addition to detecting complications of THA, SPECT-CT enables multiplanar reconstruction and manipulation of imaging data, which may aid surgical planning. SPECT-CT is an important adjunct to conventional imaging in the management of post-THA complications. It is vital that radiologists are able to identify the specific features of different complications and use this novel imaging technique to guide management. In this article, the use of SPECT-CT to follow post-THA complications, including aseptic loosening, periprosthetic infection, histiocytic reactions, periprosthetic fractures, polyethylene wear, and pseudotumour formation, will be reviewed.


Assuntos
Artroplastia de Quadril , Articulação do Quadril/diagnóstico por imagem , Imagem Multimodal , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Humanos
16.
J Neuroendocrinol ; 25(10): 898-909, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23895426

RESUMO

Maternal care is the newborn's first experience of social interaction, and this influences infant survival, development and social competences throughout life. We recently found that postpartum blocking of the endocannabinoid receptor-1 (CB1R) altered maternal behaviour. In the present study, maternal care was assessed by the time taken to retrieve pups, pups' ultrasonic vocalisations (USVs) and pup body weight, comparing CB1R deleted (CB1R KO) versus wild-type (WT) mice. After culling on postpartum day 8, hippocampal expression of oxytocin receptor (OXTR), brain-derived neurotrophic factor (BDNF) and stress-mediating factors were evaluated in CB1R KO and WT dams. Comparisons were also performed with nulliparous (NP) CB1R KO and WT mice. Compared to WT, CB1R KO dams were slower to retrieve their pups. Although the body weight of the KO pups did not differ from the weight of WT pups, they emitted fewer USVs. This impairment of the dam-pup relationship correlated with a significant reduction of OXTR mRNA and protein levels among CB1R KO dams compared to WT dams. Furthermore, WT dams exhibited elevated OXTR mRNA expression, as well as increased levels of mineralocorticoid and glucocorticoid receptors, compared to WT NP mice. By contrast, CB1R KO dams showed no such elevation of OXTR expression, alongside lower BDNF and mineralocorticoid receptors, as well as elevated corticotrophin-releasing hormone mRNA levels, when compared to CB1R KO NP. Thus, it appears that the disruption of endocannabinoid signalling by CB1R deletion alters expression of the OXTR, apparently leading to deleterious effects upon maternal behaviour.


Assuntos
Comportamento Animal , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Hipocampo/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Receptores de Canabinoides/metabolismo , Receptores de Ocitocina/metabolismo , Animais , Sequência de Bases , Primers do DNA , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Ocitocina/sangue , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Ocitocina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Rev Sci Instrum ; 84(12): 123505, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24393076

RESUMO

Measurements of the response of LaBr3(Ce) to 2.5 MeV neutrons have been carried out at the Frascati Neutron Generator and at tokamak facilities with deuterium plasmas. The observed spectrum has been interpreted by means of a Monte Carlo model. It is found that the main contributor to the measured response is neutron inelastic scattering on (79)Br, (81)Br, and (139)La. An extrapolation of the count rate response to 14 MeV neutrons from deuterium-tritium plasmas is also presented. The results are of relevance for the design of γ-ray diagnostics of fusion burning plasmas.

18.
Rev Sci Instrum ; 83(10): 10D730, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23126902

RESUMO

The critical issues in the development of diagnostics, which need to work robust and reliable under quasi-steady state conditions for the discharge durations of 30 min and which cannot be maintained throughout the one week duration of each operation phase of the Wendelstein 7-X stellarator, are being discussed.

19.
Int J Sports Med ; 32(11): 822-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22052034

RESUMO

Heat acclimation (HA) often starts in a moderately hot environment to prevent thermal overload and stops immediately prior to athletic activities. The aims of this study were (1) to establish whether acclimation to a moderately hot climate is sufficient to provide full acclimation for extreme heat and (2) to investigate the physiological responses to heat stress during the HA decay period. 15 male subjects exercised for 9 consecutive days at 26° C Wet Bulb Globe Temperature (WBGT) and 3 days at 32° C WBGT on a cycle ergometer for up to 2 h per day and repeated the exercise 3, 7 and 18 days later in 26° C WBGT. Rectal temperature (T (re)) and heart rate (HR) were measured during 60 min of steady state exercise (∼45% of maximum oxygen uptake). During days 1-9, end-exercise T (re) was reduced from 38.7±0.1 to a plateau of 38.2±0.1° C (p<0.05), HR was reduced from 156±10 to 131±11 bpm (p<0.05). No changes in HR and T (re) occurred during the 3 days in the very hot environment. However, T (re) during rest and exercise were significantly lower by 0.4-0.5° C after HA compared with day 9, suggesting that heat acclimation did not decay but resulted in further favourable adaptations.


Assuntos
Aclimatação/fisiologia , Exercício Físico/fisiologia , Transtornos de Estresse por Calor/fisiopatologia , Temperatura Alta , Adulto , Ciclismo/fisiologia , Temperatura Corporal/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Esforço Físico/fisiologia , Fatores de Tempo , Adulto Jovem
20.
Rev Sci Instrum ; 81(10): 10E133, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21033995

RESUMO

The status of the diagnostic developments for the quasistationary operable stellarator Wendelstein 7-X (maximum pulse length of 30 min at 10 MW ECRH heating at 140 GHz) will be reported on. Significant emphasis is being given to the issue of ECRH stray radiation shielding of in-vessel diagnostic components, which will be critical at high density operation requiring O2 and OXB heating.

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