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1.
BMJ Open ; 11(10): e050216, 2021 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-34706952

RESUMO

OBJECTIVE: Hypoalbuminaemia is an important prognostic factor. It may be associated with poor nutritional states, chronic heart and kidney disease, long-standing infection and cancer. Hypotension is a hallmark of circulatory failure. We evaluated hypoalbuminaemia and hypotension synergism as predictor of in-hospital mortality and intensive care unit (ICU) admission. DESIGN: We retrospectively analysed emergency department (ED) visits from January 2011 to December 2019. SETTING: Data were retrieved from five Mount Sinai health system hospitals, New York. PARTICIPANTS: We included consecutive ED patients ≥18 years with albumin measurements. PRIMARY AND SECONDARY OUTCOME MEASURES: Clinical outcomes were in-hospital mortality and ICU admission. The rates of these outcomes were stratified by systolic blood pressure (SBP) (<90 vs ≥90 mm Hg) and albumin levels. Variables included demographics, presenting vital signs, comorbidities (measured as ICD codes) and other common blood tests. Multivariable logistic regression models analysed the adjusted OR of different levels of albumin and SBP for predicting ICU admission and in-hospital mortality. The models were adjusted for demographics, vital signs, comorbidities and common laboratory results. Patients with albumin 3.5-4.5 g/dL and SBP ≥90 mm Hg were used as reference. RESULTS: The cohort included 402 123 ED arrivals (27.9% of total adult ED visits). The rates of in-hospital mortality, ICU admission and overall admission were 1.7%, 8.4% and 47.1%, respectively. For SBP <90 mm Hg and albumin <2.5 g/dL, mortality and ICU admission rates were 34.0% and 40.6%, respectively; for SBP <90 mm Hg and albumin ≥2.5 g/dL 8.2% and 24.1%, respectively; for SBP ≥90 mm Hg and albumin <2.5 g/dL 11.4% and 18.6%, respectively; for SBP ≥90 mm Hg and albumin 3.5-4.5 g/dL 0.5% and 6.4%, respectively. Multivariable analysis showed that in patients with hypotension and albumin <2.5 g/dL the adjusted OR for in-hospital mortality was 37.1 (95% CI 32.3 to 42.6), and for ICU admission was 5.4 (95% CI 4.8 to 6.1). CONCLUSION: Co-occurrence of hypotension and hypoalbuminaemia is associated with poor hospital outcomes.


Assuntos
Hipoalbuminemia , Hipotensão , Adulto , Estudos de Coortes , Cuidados Críticos , Serviço Hospitalar de Emergência , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Estudos Retrospectivos
2.
Aging Ment Health ; 25(7): 1246-1253, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32524829

RESUMO

OBJECTIVES: The current study focuses on the association between social anxiety (e.g. fear of social interactions or negative judgment by others) and intimate loneliness (lacking meaningful relationships, i.e. having low quantity/quality of intimate companionship) in older and younger adults. We assessed whether social anxiety, a factor which hampers intimacy, may be associated with intimate loneliness to a greater extent in older adults versus younger adults. METHOD: Measures of loneliness (Revised UCLA loneliness scale) and social anxiety (Leibowitz social anxiety scale) were obtained from 342 participants (220 younger adults, age = 19-40, and 122 older adults, age = 61-89). RESULTS: Age differences were evident for non-intimate types of loneliness but not for intimate loneliness. Further, older adults were less socially anxious. Critically, the strength of the social anxiety-intimate loneliness link was more robust among older adults. Effects remained significant after controlling for demographic and computer/social media variables. CONCLUSIONS: Older adults with high levels of social anxiety displayed greater intimate loneliness relative to younger adults. On a theoretical level, the results reveal that the pruning mechanism of investing more in closer and more rewarding relationships among older adults may be challenged under high social anxiety. The results suggest that older adults with higher intimate loneliness may benefit from interventions aimed at decreasing their social anxiety.


Assuntos
Ansiedade , Solidão , Idoso , Idoso de 80 Anos ou mais , Medo , Humanos , Relações Interpessoais
3.
S Afr Med J ; 110(8): 753-755, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32880301

RESUMO

The research requirement for South African specialist registration offers opportunities and challenges. For some clinicians it may spark a lifelong interest in clinical investigation, while for many others it may provide a potential publication opportunity. Integrating the specific requirements of an MMed mini-dissertation with those of standard medical publications can be difficult for first-time authors and their supervisors; published guidance caters to full-length laboratory Master's or doctoral research. We suggest that research is more likely to be publishable if it is locally relevant, has a clear clinical message and is coherently presented.


Assuntos
Dissertações Acadêmicas como Assunto , Educação de Pós-Graduação em Medicina , Editoração , Pesquisa Biomédica , Humanos , África do Sul , Especialização
4.
S Afr Med J ; 110(4): 302-307, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32657742

RESUMO

BACKGROUND: The recent amendment to the Health Professions Council of South Africa (HPCSA) Form 57 MED allows specialist registration on publication of the compulsory MMed research assignment in an accredited journal. No data exist on the conversion rate of MMed dissertations to publication. OBJECTIVES: To establish conversion rates of MMed dissertations to accredited publications. Associated variables arising from the publishing exercise were also investigated. METHODS: A total of 309 MMed dissertations, submitted between 1996 and 2017, were downloaded from the public domain. Each dissertation was recorded as to format, submission year, awarding university and clinical discipline. Electronic searches determined publication outcomes. Journal title, accreditation status, year of publication, registrar position on author ranking and publication type were extracted for each output. Descriptive analysis was undertaken and, where appropriate, Fisher's exact test at p>0.05 was used to establish statistical significance. RESULTS: A total of 116 dissertations were published at an overall conversion rate of 37.5%, culminating in 136 outputs. Publication-ready dissertations had a significantly higher conversion rate (60.3%) than monographs (30.5%) (p>0.0001). All but 6 of the 80 publishing journals were accredited. SAMJ was the journal of choice for 13% of papers. The registrar was the first author in the majority of publications. In the case of monographs, 66% were published after dissertation submission compared with 50% of publication-ready formats. CONCLUSIONS: Conversion of the South African MMed dissertation into a journal-accredited scientific article was achieved in 60.3% of publication-ready-format submissions, suggesting that the HPCSA amendment facilitating specialist registration is attainable. Retrospective reviews of dissertations provide valuable insights to improve understanding of the contentious issue of the registrar research requirement that permits specialist registration.


Assuntos
Dissertações Acadêmicas como Assunto , Educação Médica , Política de Saúde , Editoração/estatística & dados numéricos , Especialização , Acreditação , Definição da Elegibilidade , Humanos , Publicações Periódicas como Assunto , Estudos Retrospectivos , África do Sul
5.
S Afr Med J ; 109(4): 254-258, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-31084691

RESUMO

BACKGROUND: The 2011 Health Professions Council of South Africa mandate requires a research component in the form of an MMed degree to permit specialist registration. Registrars consider that the time required to complete an MMed interferes with clinical training, service delivery obligations, and study and exam time. Net research time to completion is difficult to establish because MMed research activity is often intermittent, starting and finishing anywhere within the 4-year clinical training period. Conversely, gross dissertation completion time (DCT) is easily calculated by subtracting the ethics approval date from the dissertation submission date. OBJECTIVES: To use gross DCT as a proxy to assess the time needed by registrars to finish the required research project. Additionally, the effect of four variables, namely dissertation format, clinical discipline, university research resources and the introduction of the 2011 ruling on gross DCT, was determined. METHODS: The sample was 213 MMed dissertations, downloaded from the public domain. The dissertation submission date was subtracted from the ethics approval date to give the gross DCT in months. Descriptive analysis and χ2 testing were used to determine the effects of the four variables on gross DCT, with significance set at p<0.05. A 12-month proposal preparation time was added to the gross DCT to fully reflect the MMed research timeline. RESULTS: Sampled dissertations were from 2005 to 2017 and all eight MMed training universities were represented, as were 23 clinical disciplines. The mean (standard deviation) gross DCT was 31.0 (19.6) months, with a wide completion range of 0.2 - 109 months. When 12 months' proposal preparation time was added, gross mean research completion time rose to 43 months (31 + 12 = 43). A mere 41% of dissertations were sufficiently concluded to free up the final year for exam preparation. Gross DCT was not significantly affected by the 2011 requirement, university resources or clinical discipline. Dissertation format (publication ready v. monograph) significantly decreased gross DCT (p=0.01). CONCLUSIONS: Large standard deviations and a wide range of finishing times detract from the positive findings that most dissertations were completed within the 4-year clinical training time period. Publication-ready dissertations significantly shortened MMed completion time. Unique study and work commitments and lack of research experience challenge speedy MMed completion. Existing research and supervisory supportive structures should be remodelled to better suit the research needs of the andragogic specialist registrar.


Assuntos
Dissertações Acadêmicas como Assunto , Pesquisa Biomédica/educação , Educação de Pós-Graduação em Medicina , Pesquisa Biomédica/normas , Pesquisa Biomédica/estatística & dados numéricos , Educação de Pós-Graduação em Medicina/métodos , Educação de Pós-Graduação em Medicina/normas , Educação de Pós-Graduação em Medicina/estatística & dados numéricos , Humanos , África do Sul , Especialização/normas , Fatores de Tempo
6.
J Hum Hypertens ; 30(8): 498-502, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26674757

RESUMO

Hypertensive emergency (HE) is a life-threatening condition that requires immediate blood pressure (BP) reduction. Although it has been on the decline, the incidence of HE has recently increased in a few countries. The aim of the present retrospective study was to evaluate the incidence, aetiology and 1-year mortality of HE in a large medical centre over a 20-year period (1991-2010). The electronic medical records of all patient files who were hospitalized in the Chaim Sheba Medical Center in Israel from 1991 to 2010 with a primary diagnosis (at admission or discharge) of Malignant Hypertension, Hypertensive Emergency or Accelerated Hypertension were retrieved and analysed. The study interval was divided into four periods of 5 years each. Among 306 files reviewed, only 142 patients had a true HE. Average age at presentation was 63.3±16.5 years. Men were younger than women (59±16 vs 68±16 years; P<0.001). At presentation, most patients (80.3%) had been diagnosed with essential hypertension previously and were undertreated. Average maximum mean arterial pressure (MAP) was higher in men (169±22 mm Hg) than in women (161±17 mm Hg; P=0.026). The rate of HE decreased over the course of the study, from 12.7/100 000 admissions during 1991-1995 to 6.2/100 000 admissions (2006-2010). Similarly, 1-year mortality decreased from 16.7 to 3.6%. The rate of HE has decreased and the prognosis has improved over the last two decades. Appropriate BP control of patients with essential hypertension may further decrease the risk of HE.


Assuntos
Pressão Arterial , Emergências , Hipertensão Maligna/mortalidade , Hipertensão/mortalidade , Encaminhamento e Consulta , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Pressão Arterial/efeitos dos fármacos , Registros Eletrônicos de Saúde , Feminino , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipertensão Maligna/diagnóstico , Hipertensão Maligna/tratamento farmacológico , Hipertensão Maligna/fisiopatologia , Incidência , Israel/epidemiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
7.
Eur J Nutr ; 53(3): 973-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24158651

RESUMO

PURPOSE: Cumulative evidence suggests that moderate red wine consumption protects the cardiovascular system. The effect of cultured cells derived from red grape berry (RGC) on blood pressure (BP) has not been investigated. We therefore studied the antihypertensive effects of oral consumption of RGC in experimental rat model of metabolic-like syndrome and assessed its effect on human umbilical vein endothelial cells (HUVECs). METHODS: Forty male Sprague-Dawley rats were fed for 5 weeks with either a high fructose diet (HFD) (n = 10) or HFD supplemented, during the last 2 weeks, with different doses (200, 400 and 800 mg/kg/day) of RGC suspended in their food (n = 30). BP, plasma triglycerides, insulin and adiponectin levels were measured at the beginning and after 3 and 5 weeks of diet. RGC effect on vasodilatation was evaluated by its ability to affect endothelin-1 (ET-1) production and endothelial nitric oxide synthase (eNOS) expression in HUVECs. RESULTS: BP, plasma triglycerides, insulin and adiponectin increased significantly in rats fed with a HFD. The increase in BP, plasma triglycerides and insulin was attenuated by RGC supplementation. Incubation of HUVECs with RGC demonstrated a concentration-dependent inhibition of ET-1 secretion and increase in the level of eNOS, signaling a positive effect of RGC on vasodilatation. CONCLUSION: In rats with metabolic-like syndrome, RGC decreased BP and improved metabolic parameters. These beneficial effects may be mediated by the cell constituents, highly rich with polyphenols and resveratrol, reside in their natural state.


Assuntos
Anti-Hipertensivos/uso terapêutico , Suplementos Nutricionais , Frutas/química , Hipertensão/prevenção & controle , Síndrome Metabólica/dietoterapia , Extratos Vegetais/uso terapêutico , Vitis/química , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/metabolismo , Células Cultivadas , Endotelina-1/metabolismo , Frutas/citologia , Frutas/metabolismo , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hiperinsulinismo/etiologia , Hiperinsulinismo/prevenção & controle , Hipertensão/etiologia , Hipertrigliceridemia/etiologia , Hipertrigliceridemia/prevenção & controle , Hipolipemiantes/administração & dosagem , Hipolipemiantes/metabolismo , Hipolipemiantes/uso terapêutico , Masculino , Síndrome Metabólica/fisiopatologia , Óxido Nítrico Sintase Tipo III/metabolismo , Pigmentos Biológicos/metabolismo , Extratos Vegetais/administração & dosagem , Extratos Vegetais/metabolismo , Ratos Sprague-Dawley , Vasodilatadores/administração & dosagem , Vasodilatadores/metabolismo , Vasodilatadores/uso terapêutico , Vitis/citologia , Vitis/metabolismo
8.
AJNR Am J Neuroradiol ; 34(5): 951-7, S1-3, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23179649

RESUMO

BACKGROUND AND PURPOSE: Cognitive impairment is frequent among patients with mild traumatic brain injury despite the absence of detectable damage on conventional MR imaging. In this study, the quantitative MR imaging techniques DTI, DKI, and ASL were used to measure changes in the structure and function in the thalamus and WM of patients with MTBI during a short follow-up period, to determine whether these techniques can be used to investigate relationships with cognitive performance and to predict outcome. MATERIALS AND METHODS: Twenty patients with MTBI and 16 controls underwent MR imaging at 3T and a neuropsychological battery designed to yield measures for attention, concentration, executive functioning, memory, learning, and information processing. MK, FA, MD, and CBF were measured in the thalamus by using region-of-interest analysis and in WM by using tract-based spatial statistics. Analyses were performed comparing regional imaging measures of subject groups and the results of testing of their associations with neuropsychological performance. RESULTS: Patients with MTBI exhibited significant differences from controls for DTI, DKI, and ASL measures in the thalamus and various WM regions both within 1 month after injury and >9 months after injury. At baseline, DTI and DKI measures in the thalamus and various WM regions were significantly associated with performance in different neuropsychological domains, and cognitive impairment was significantly associated with MK in the thalamus and FA in optic radiations. CONCLUSIONS: Combined application of DTI, DKI, and ASL to study MTBI might be useful for investigating dynamic changes in the thalamus and WM as well as cognitive impairment during a short follow-up period, though the small number of patients examined did not predict outcome.


Assuntos
Lesões Encefálicas/diagnóstico , Transtornos Cognitivos/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Angiografia por Ressonância Magnética/métodos , Fibras Nervosas Mielinizadas/patologia , Tálamo/patologia , Adolescente , Adulto , Lesões Encefálicas/complicações , Transtornos Cognitivos/etiologia , Feminino , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
9.
SADJ ; 68(9): 412-4, 416-21, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24660413

RESUMO

This study compared digital and visual colour tooth colour assessment methods in a sample of 99 teeth consisting of incisors, canines and pre-molars. The teeth were equally divided between Control, Ozicure Oxygen Activator bleach and Opalescence Quick bleach and subjected to three treatments. Colour readings were recorded at nine intervals by two assessment methods, VITA Easyshade and VITAPAN 3D MASTER TOOTH GUIDE, giving a total of 1782 colour readings. Descriptive and statistical analysis was undertaken using a GLM test for Analysis of Variance for a Fractional Design set at a significance of P < 0.05. Atomic force micros copy was used to examine treated ename surfaces and establish surface roughness. Visual tooth colour assessment showed significance for the independent variables of treatment, number of treatments, tooth type and the combination tooth type and treatment. Digital colour assessment indicated treatment and tooth type to be of significance in tooth colour change. Poor agreement was found between visual and digital colour assessment methods for Control and Ozicure Oxygen Activator treatments. Surface roughness values increased two-fold for Opalescence Quick specimens over the two other treatments, implying that increased light scattering improved digital colour reading. Both digital and visual colour matching methods should be used in tooth bleaching studies to complement each other and to compensate for deficiencies.


Assuntos
Percepção de Cores , Colorimetria/métodos , Esmalte Dentário/anatomia & histologia , Clareamento Dental , Dente/anatomia & histologia , Cor , Esmalte Dentário/efeitos dos fármacos , Humanos , Microscopia de Força Atômica , Oxidantes/farmacologia , Espectrofotometria , Propriedades de Superfície , Dente/efeitos dos fármacos
10.
SADJ ; 67(7): 332-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23951788

RESUMO

INTRODUCTION: This in vitro study compared a new tooth bleaching product, Ozicure Oxygen Activator (O3, RSA) with Opalescence Quick (Ultradent, USA) using a randomised block design to assess tooth colour change. AIM: Colour change, stability and relapse in canine, incisor and premolar teeth was assessed following three bleach treatments and subsequent tooth colour assessment. METHODS: Ninety nine teeth (canines, incisors and premolars), which were caries free, had no surface defects and were within the colour range 1M2 and 5M3 were selected. Teeth were randomly divided into the three experimental groups: Opalescence Quick, Ozicure Oxygen Activator and control. The three experimental groups received three treatments of one hour each over three consecutive days. Tooth colour was assessed using the Vitapan 3D Master Tooth Guide (VITA, Germany). A General Linear Models test for analysis of variance for a fractional design with significance set at P < 0.05 was used to test for significance. RESULTS: Both bleaching methods significantly lightened the teeth (P < 0.0001). Tooth colour change was mainly after the first hour of tooth bleaching. The tooth type was significant in tooth colour change (P = 0.0416). Tooth colour relapse and resistance to colour change were observed. CONCLUSIONS: Ozicure Oxygen Activator bleached teeth in a manner and to an extent similar to Opalescence Quick.


Assuntos
Ozônio/uso terapêutico , Clareadores Dentários/uso terapêutico , Clareamento Dental/métodos , Dente/efeitos dos fármacos , Dente Pré-Molar/efeitos dos fármacos , Cor , Dente Canino/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Peróxido de Hidrogênio/uso terapêutico , Incisivo/efeitos dos fármacos , Teste de Materiais , Peróxidos/uso terapêutico , Polivinil/uso terapêutico , Fatores de Tempo , Dente/patologia , Clareamento Dental/instrumentação , Ureia/análogos & derivados , Ureia/uso terapêutico
11.
Diabet Med ; 26(3): 253-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19317820

RESUMO

AIMS: Obesity is linked to increased morbidity and mortality risk in both the general population and in patients with diabetes mellitus; however, recent reports suggest that, in hospitalized elderly individuals, the association between body mass index (BMI) and mortality may be inverse. The present study sought to investigate the association between BMI and survival in hospitalized elderly individuals with diabetes mellitus. METHODS: The medical records of 470 patients (226 males, mean age of 81.5 +/- 7.0 years) admitted to an acute geriatric ward between 1999 and 2000 were reviewed. Of the 140 patients with diabetes mellitus, 122 had more than 6 months of follow-up and were included in this analysis. Patients were followed up until 31 August 2004. Mortality data were extracted from death certificates. RESULTS: During a mean follow-up of 3.7 +/- 1.6 years, 69 (56.6%) subjects died, 31 (25.4%) from cardiovascular causes. Those who died from any cause had lower baseline BMI than those who survived (24.0 +/- 4.0 vs. 27.1 +/- 4.3 kg/m(2); P < 0.0001). Similarly, those who died of cardiovascular causes had lower baseline BMI than those who did not (23.7 +/- 3.6 vs. 25.9 +/- 4.5, P = 0.01). BMI was inversely associated with all-cause [relative risk (RR) 0.89, 95% confidence interval (CI) 0.83-0.96, P = 0.002] and cardiovascular death (RR 0.83, 95% CI 0.74-0.93, P = 0.002) even after controlling for age, sex, smoking, dyslipidaemia and reason for hospital admission. CONCLUSIONS: In very elderly subjects with diabetes mellitus, increased BMI was associated with reduced mortality risk.


Assuntos
Índice de Massa Corporal , Doenças Cardiovasculares/mortalidade , Angiopatias Diabéticas/mortalidade , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Causas de Morte , Feminino , Seguimentos , Humanos , Masculino , Fatores de Risco , Estatística como Assunto
12.
Horm Metab Res ; 41(1): 46-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18949682

RESUMO

Adiponectin is an important vascular protective substance whose levels are reduced in states of insulin resistance. The relationships between plasma insulin levels and adiponectin are not fully understood, and it is not known whether it is the elevated circulating levels of insulin or insulin resistance that directly affects adiponectin levels. The present study evaluates the direct effect of chronic hyperinsulinemia on plasma adiponectin levels. Male Sprague-Dawley rats were treated with insulin (n=15) administered by a sustained-release implant or were given a sham implantation (n=10) as a control group. Body weight, systolic blood pressure, plasma glucose, triglycerides, insulin, and adiponectin were measured at baseline and after 20 and 40 d of treatment. Insulin-treated rats and controls showed a similar increase in body weight. The insulin-treated group had a significant increase in plasma insulin levels and a decrease in plasma glucose levels compared with the sham group, with no change in blood pressure or triglyceride levels. Adiponectin levels remained unchanged despite the significant increase in insulin levels. High circulating insulin levels do not affect plasma adiponectin levels. These results support the concept that the primary defect that results in insulin resistance and hyperinsulinemia is responsible for the altered plasma adiponectin levels in the metabolic syndrome and type 2 diabetes.


Assuntos
Adiponectina/sangue , Hiperinsulinismo/sangue , Animais , Glicemia/análise , Glicemia/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Doença Crônica , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/fisiopatologia , Insulina/sangue , Insulina/farmacologia , Sistemas de Infusão de Insulina/veterinária , Resistência à Insulina/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Triglicerídeos/sangue
14.
SADJ ; 63(1): 010-4, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18543733

RESUMO

A descriptive study of SA IADR Conference participation 1967-2004 showed that both membership numbers and conference presentations have declined by half over the past 20 years. Of the total of 3 259 presentations, from mainly the six Schools of Oral Health Sciences (SOHS), the majority were from SOHS 1, followed by the SOHS 2, 3, 5, 4 and 6. Productivity of individual SOHS has changed over the years. Number of annual presentations per school has varied according to the organising school and the distance of the school from the conference venue. Research prizes are well supported. Research active "drivers" have high personal research productivity but do not significantly influence (P > 0.05) the number of conference presentations of their respective schools.


Assuntos
Congressos como Assunto/estatística & dados numéricos , Pesquisa em Odontologia/estatística & dados numéricos , Distinções e Prêmios , Pesquisa em Odontologia/economia , Pesquisa em Odontologia/organização & administração , Eficiência , Humanos , Faculdades de Odontologia/estatística & dados numéricos , África do Sul
15.
J Phys Chem B ; 112(24): 7166-70, 2008 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-18491939

RESUMO

We describe a general method of finding the transport properties of molecules in polymer films by photolysis. Poly(methyl methacrylate) samples held at different temperatures are exposed to UV radiation at discrete wavelengths, and the time evolution of the volatile photoproducts are detected with a quadrupole mass spectrometer. A diffusion model is used to fit the experimental data and deduce diffusion coefficients for the main photoproduct methyl formate. The average value at room temperature was equal to 1.9 x 10 (-11) cm (2) s (-1) at all wavelengths investigated. Together with the values derived at other temperatures, an Arrhenius plot was obtained and the activation energy for methyl formate diffusion within the polymeric thin film calculated from the slope of the graph. We envision that this new method will find application to a variety of problems involving the mass transport of molecules through boundary layers of single or multilayer thin film structures.

16.
Eur J Dent Educ ; 12(2): 69-74, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18412733

RESUMO

The careers of 131 dental research trainees were followed (1954-2007) to establish whether and how they utilised their research training in keeping with clinical research workforce needs. The Dental Research Institute database was used to obtain trainee demographic, teaching and research outputs which were examined according to degree types: PhD (18); MSc (55); MDent (42) and dropout (16). Current careers show that 48% are in exclusive private practice and 15% in exclusive academia with further 15% practitioners having academic links via sessional teaching or research at a dental school. Most (63%) have remained in South Africa but emigration is high amongst the PhD and MSc groups. Forty-one per cent of the cohort is of age

Assuntos
Pesquisa em Odontologia/educação , Pesquisadores/estatística & dados numéricos , Academias e Institutos , Adulto , Escolha da Profissão , Bases de Dados Factuais , Emigração e Imigração , Docentes de Odontologia , Humanos , Pessoa de Meia-Idade , Prática Privada , Editoração , Estudos Retrospectivos , África do Sul , Especialidades Odontológicas , Recursos Humanos
17.
Am J Transplant ; 8(5): 965-74, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18341685

RESUMO

While the function of each organ is used by each transplant team to assess suitability for transplantation, little is known about the donor characteristics and clinical interventions that contribute toward overall organ transplantation potential. We conduct a retrospective review of United Network for Organ Sharing (UNOS) deceased donor registry data from January 2005 to December 2006. This registry contains all deceased donors from whom organs were recovered during this time period (n = 15,601). Ordinary least-squares (OLS) regression models using variables in the registry are estimated to predict the number of organs transplanted. Outcome is the number of organs transplanted per donor. Organ yield is found to depend significantly on donor age, anoxia as cause of death, history of myocardial infarction (MI), hypertension and/or diabetes, body mass index (BMI), B or AB blood type, cocaine and/or cigarette use and hepatitis infection (p < 0.01). In addition, the clinical interventions of steroid administration, desmopressin (DDAVP) and diuretic usage, as well as oxygenation, are associated with organ yield. Both intrinsic donor characteristics and medical management practice are observed to be highly variable across organ procurement organizations (OPOs). These findings may provide important information to explore and assess the efficacy of clinical interventions, compare OPO performance and point to best practices.


Assuntos
Cadáver , Doadores de Tecidos/estatística & dados numéricos , Obtenção de Tecidos e Órgãos/métodos , Morte Encefálica , Seleção do Doador , Humanos , Seleção de Pacientes , Sistema de Registros , Alocação de Recursos/métodos , Estados Unidos , Listas de Espera
18.
Rev Sci Instrum ; 79(2 Pt 1): 025106, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18315328

RESUMO

The materials of spacecraft external surfaces in low Earth orbit (LEO) are exposed to the various constituents of the space environment, including atomic oxygen (AO) and solar ultra violet (UV) radiation. Material degradation and erosion by LEO are simulated in ground laboratories using a variety of experimental facilities, each with their respective limitations. rf oxygen plasma is a simulation facility widely used for materials screening for LEO application. However, the complex plasma environment, which contains, in addition to the neutral oxygen atoms, excited species, electrons, and ions as well as vacuum ultraviolet (VUV) radiation, might lead to erroneous determination of materials reactivity with respect to LEO. This paper describes the development of a simple, low cost rf plasma system to produce a well-defined AO and VUV environment. The new system constrained the afterglow flow through two right-angle turns. The afterglow was characterized at three specific locations by (i) optical emission spectroscopy for assessment of electronically excited states, (ii) current measurements, and (iii) UV radiation measurements. KaptonR samples were exposed at the three specific locations in the system and characterized by mass loss for etch rate evaluation, and atomic force microscopy for surface modification. It was found that there is a significant reduction in ionic species, excited species, and UV radiation as the afterglow advances through the right-angle turns. The reduction in charged particle flux is due to recombination within the afterglow as well as neutralization by colliding with the grounded metal chamber walls; similar decrease in UV radiation flux occurs through radiation absorption by the chamber walls. Finally, it is shown that the ground state AO is the dominant reactive specie of the plasma afterglow after passing through the two right-angle turns.

19.
Horm Metab Res ; 40(2): 147-54, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18283633

RESUMO

Type 1 diabetes mellitus (T1DM) is a disease that results from the selective autoimmune destruction of insulin-producing beta-cells. This disease process lends itself to cellular therapy because of the single cell nature of insulin production. Murine models have provided opportunities for the study of cellular therapies for the treatment of diabetes, including the investigation of islet transplantation, and also the possibility of stem cell therapies and islet regeneration. Studies in islet transplantation have included both allo- and xeno-transplantation and have allowed for the study of new approaches for the reversal of autoimmunity and achieving immune tolerance. Stem cells from hematopoietic sources such as bone marrow and fetal cord blood, as well as from the pancreas, intestine, liver, and spleen promise either new sources of islets or may function as stimulators of islet regeneration. This review will summarize the various cellular interventions investigated as potential treatments of T1DM.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Transplante de Células-Tronco , Animais , Terapia Baseada em Transplante de Células e Tecidos , Humanos
20.
Horm Metab Res ; 39(5): 384-8, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17533582

RESUMO

BACKGROUND: Adiponectin is an adipose tissue-specific protein, which possesses anti-atherogenic and antidiabetic properties, yet its plasma levels are decreased in subjects with metabolic syndrome. Although high fat diet has been linked to hypoadiponectinemia, the effect of high-carbohydrate diet on adiponectin levels is not known. Therefore, we studied the effect of high-carbohydrate diet on adiponectin levels in the rat models of hypertension and insulin resistance. METHODS: Rats were randomly assigned to the high carbohydrate diet [Sprague-Dawley rats with fructose enriched diet (SDR-F) and spontaneously hypertensive rats with sucrose enriched diet (SHR-S model)] or chow diet (Control group). Rats were followed for 6 weeks (SDR-F model) and 8 weeks (SHR-S model). Body weight, systolic blood pressure, plasma levels of glucose, insulin, triglycerides and adiponectin, were recorded. RESULTS: Both models were associated with features of the metabolic syndrome, namely, high insulin levels, increased blood pressure and triglyceride levels. Plasma adiponectin levels did not change in the control groups. In contrast, adiponectin levels increased by 39 and 30% compared to baseline following four and six weeks of fructose enriched diet in SDR (from 3.3+/-0.2 to 4.5+/-0.4 and 4.3+/-0.2 microg/ml, respectively, p<0.05). Likewise, five and eight weeks of sucrose enriched diet in SHR, induced a 54 and 81% increase in adiponectin levels compared to baseline (from 4.2+/-0.3 to 6.3+/-0.3 and 7.3+/-0.5 microg/ml, respectively, p<0.01). CONCLUSION: Metabolic stress with a high-carbohydrate diet increases plasma levels of adiponectin. Further studies will elucidate whether this is a transitory compensatory mechanism or a sign of target organ resistance to adiponectin.


Assuntos
Adiponectina/sangue , Carboidratos da Dieta/farmacologia , Síndrome Metabólica/sangue , Animais , Pressão Sanguínea/fisiologia , Dieta , Frutose/farmacologia , Hipertensão/fisiopatologia , Resistência à Insulina/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ratos Sprague-Dawley , Sacarose/farmacologia , Triglicerídeos/sangue , Aumento de Peso/efeitos dos fármacos
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