Comparison of sweat rate during graded exercise and the local rate induced by pilocarpine

Centrally stimulated sweat rate produced by graded exercise until exhaustion was compared to the local sweat rate induced by pilocarpine, often used as a sweating index for healthy individuals. Nine young male volunteers (22 ± 4 years) were studied in temperate environment in two situations: at rest and during progressive exercise with 25 W increases every 2 min until exhaustion, on a cycle ergometer. In both situations, sweating was induced on the right forearm with 5 ml 0.5 percent pilocarpine hydrochloride applied by iontophoresis (1.5 mA, 5 min), with left forearm used as control. Local sweat rate was measured for 15 min at rest. During exercise, whole-body sweat rate was calculated from the body weight variation. Local sweat rate was measured from the time when heart rate reached 150 bpm until exhaustion and was collected using absorbent filter paper. Pharmacologically induced local sweat rate at rest (0.4 ± 0.2 mg cm-2 min-1) and mean exercise-induced whole-body sweat rate (0.4 ± 0.1 mg cm-2 min-1) were the same (P > 0.05) but were about five times smaller than local exercise-induced sweat rate (control = 2.1 ± 1.4; pilocarpine = 2.7 ± 1.2 mg cm-2 min-1), indicating different sudorific mechanisms. Both exercise-induced whole-body sweat rate (P < 0.05) and local sweat rate (P < 0.05) on control forearm correlated positively with pilocarpine-induced local sweat rate at rest. Assuming that exercise-induced sweating was a result of integrated physiological mechanisms, we suggest that local and whole-body sweat rate measured during graded exercise could be a better sweating index than pilocarpine.

Heat storage rate and acute fatigue in rats

Thermal environmental stress can anticipate acute fatigue during exercise at a fixed intensity ( percentVO2max). Controversy exists about whether this anticipation is caused by the absolute internal temperature (Tint, ºC), by the heat storage rate (HSR, cal/min) or by both mechanisms. The aim of the present study was to study acute fatigue (total exercise time, TET) during thermal stress by determining Tint and HSR from abdominal temperature. Thermal environmental stress was controlled in an environmental chamber and determined as wet bulb globe temperature (ºC), with three environmental temperatures being studied: cold (18ºC), thermoneutral (23.1ºC) or hot (29.4ºC). Six untrained male Wistar rats weighing 260-360 g were used. The animals were submitted to exercise at the same time of day in the three environments and at two treadmill velocities (21 and 24 m/min) until exhaustion. After implantation of a temperature sensor and treadmill adaptation, the animals were submitted to a Latin square experimental design using a 2 x 3 factorial scheme (velocity and environment), with the level of significance set at P<0.05. The results showed that the higher the velocity and the ambient temperature, the lower was the TET, with these two factors being independent. This result indicated that fatigue was independently affected by both the increase in exercise intensity and the thermal environmental stress. Fatigue developed at different Tint and HSR showed the best inverse relationship with TET. We conclude that HSR was the main anticipating factor of fatigue

Effects of aluminum on the mechanical and electrical activity of the Langendorff-perfused rat heart

The effect of aluminum (Al3+) chloride (1,5,10,50 and 100 µM) on myocardial electromechanical activity was studied in 10 Langendorff-perfused hearts from adult female Wistar rats. Al3+ decreased the development of isovolumic systolic pressure from 34.3 ñ 2.95 mmHg under control conditions to 11.8 ñ 1.53 mmHg at 100µM AlCl3 (P<0.01) (diastolic pressure = 0 mmHg). The atrial and ventricular rates also decreased, but only with AlCl3 concentrations greater than 1µM (from 180 ñ 5 to 94 ñ 11 bpm for atrial rate and from 180 ñ 5 to 78 ñ 7 bpm for ventricular rate). Reduction of coronary flow was also observed, reaching 60 percent at 100 µM Al3+. A delay in atrioventricular conduction occurred at 10µM Al3+, increasing progressively up to 100 µM (62.3 ñ 4 ms in the Al3+ - free solution to 143 ñ 34 ms in the presence of 100 µM Al3+, P<0.01, ANOVA). QRS duration did not change as a function of increasing Al3+ concentrations (37.1 ñ 1.7 ms in the Al3+ -free solution vs 32.1 ñ 1.6 ms in the presence of 100 µM Al3+). No qualitative changes in ECG were observed. These data show that the toxic effects of Al3+ on the myocardium are reflected in reduced systolic pressure development and coronary flow and increased PR interval. These effects are discussed in terms of the inhibition of nucleotide hydrolysis by Al3+

Calcifilaxia. / Calciphylaxis

Os autores apresentam um caso de ulceracao isquemica da pele e calcificacao vascular em um paciente com uremia e hiperparatiroidismo secundario, que respondeu ao tratamento medico. Discutem a fisiopatologia, enfatizando o diagnostico clinico, laboratorial, radiologico e histopatologico e o tratamento medico conservador

Pesquisa de virus no liquido cefalorraqueano na sindrome de Vogt-Koyanagi Registro de um caso. / Virus research in cerebrospinal fluid in Vogt-Koyanagi syndrome: report of a case

Foi realizada pesquisa para isolamento e identificacao de virus no liquido cefalorraqueano de paciente com sindrome de Vogt-Koyanagi (uveo-meningoencefalite). Os resultados foram negativos. Nao pudemos caracterizar um virus responsavel pela doenca nesse caso. Esta foi a primeira pesquisa realizada nesse sentido no Brasil

Degeneracao senil de macula. / Senile macular degeneration

Os autores comentam acerca da etiopatogenia da DSM. Enfatizam a importancia das drusas.Descrevem varios casos pessoais escolhidos para ilustracao e concluem que e importante a deteccao precoce da membrana neo-vascular sub-retiniana e da fotocoagulacao da mesma como uma terapeutica disponivel na atualidade

Estudo bacteriologico em sinusites maxilares. / Bacteriological study in maxillary sinusitis

Os autores apresentam um estudo bacteriologico em infeccoes sinusais, atraves de material colhido por puncao transmeatica inferior do seio maxiliar. Em 26 pacientes estudados, 27% das culturas foram negativas; 61,5% revelaram a presenca de 1 ou mais germes anaerobios, de forma isolada ou associada com germes anaerobios; e apenas 11,5% apresentaram somente germes anaerobios, unicos ou multiplos

Sindrome de Vogt-Koyanagi: relato de um caso em gestante. / Vogt-Koyanagi syndrome: report of a case in a pregnant woman

Os autores relatam o caso de uma paciente com 28 anos, gestante, portadora de sindrome de Vogt-Koyanagi que, mesmo com o uso de corticosteroides, nao obteve recuperacao da visao. O recem-nato apresentou no bercario quadro sugestivo de meningoencefalite e faleceu com dois anos de idade apresentando manifestacoes compativeis a grave paralisia cerebral. Questiona-se a possibilidade de relacionar este fato a enfermidade da mae

Catarata congenita e sua terapeutica. / Congenital cataract and its therapy

Os autores fazem uma revisao atualizada sobre diversos aspectos das cataratas congenitas, dando sua opiniao sobre os mesmos descrevendo sua experiencia e a conduta que adotam. Analizam o periodo ideal para cirurgia, associacao desta entidade com outras anomalias, a indicacao e tecnica cirurgica, bem como a conduta pos-operatoria e a correcao optica da afacia

Rubeola congenita: sua importancia em nosso meio e sua profilaxia vacinal. / Congenital rebella: its importance in our environment and vaccine prophylaxis

Os autores pesquisaram a importancia da rubeola congenita em nosso meio, o valor da vacinacao na modificacao destes indices e o nivel de conhecimento relativo ao assunto das mulheres em idade gestacional. Para tanto,obtiveram indices de rubeola congenita em anos recentes em quatro hospitais que atendem camadas diversas do ponto de vista socio-economico da populacao da cidade de Sao Paulo,tendo entrevistado obstetras e parturientes e/ou puerperas.Concluem que a incidencia da rubeola congenita deve ser maior do que a encontrada e chamam a atencao para a pratica pouco comum do exame pre-nupcial, a baixa utilizacao da vacina preventiva da rubeola e as poucas informacoes que parturientes e puerperas tem dos riscos inerentes a esta infeccao