Rapid eye movement sleep deprivation induces an increase in acetylcholinesterase activity in discrete rat brain regions

Some upper brainstem cholinergic neurons (pedunculopontine and laterodorsal tegmental nuclei) are involved in the generation of rapid eye movement (REM) sleep and project rostrally to the thalamus and caudally to the medulla oblongata. A previous report showed that 96 h of REM sleep deprivation in rats induced an increase in the activity of brainstem acetylcholinesterase (Achase), the enzyme which inactivates acetylcholine (Ach) in the synaptic cleft. There was no change in the enzyme's activity in the whole brain and cerebrum. The components of the cholinergic synaptic endings (for example, Achase) are not uniformly distributed throughout the discrete regions of the brain. In order to detect possible regional changes we measured Achase activity in several discrete rat brain regions (medulla oblongata, pons, thalamus, striatum, hippocampus and cerebral cortex) after 96 h of REM sleep deprivation. Naive adult male Wistar rats were deprived of REM sleep using the flower-pot technique, while control rats were left in their home cages. Total, membrane-bound and soluble Achase activities (nmol of thiocholine formed min-1 mg protein-1) were assayed photometrically. The results (mean ± SD) obtained showed a statistically significant (Student t-test) increase in total Achase activity in the pons (control: 147.8 ± 12.8, REM sleep-deprived: 169.3 ± 17.4, N = 6 for both groups, P<0.025) and thalamus (control: 167.4 ± 29.0, REM sleep-deprived: 191.9 ± 15.4, N = 6 for both groups, P<0.05). Increases in membrane-bound Achase activity in the pons (control: 171.0 ± 14.7, REM sleep-deprived: 189.5 ± 19.5, N = 6 for both groups, P<0.05) and soluble enzyme activity in the medulla oblongata (control: 147.6 ± 16.3, REM sleep-deprived: 163.8 ± 8.3, N = 6 for both groups, P<0.05) were also observed. There were no statistically significant differences in the enzyme's activity in the other brain regions assayed. The present findings show that the increase in Achase activity induced by REM sleep deprivation was specific to the pons, a brain region where cholinergic neurons involved in REM generation are located, and also to brain regions which receive cholinergic input from the pons (the thalamus and medulla oblongata). During REM sleep extracellular levels of Ach are higher in the pons, medulla oblongata and thalamus. The increase in Achase activity in these brain areas after REM sleep deprivation suggests a higher rate of Ach turnover.

Student stress and quality of education

Today, managers are increasingly interested in knowing how the work in organizations aftects employees' health. Less common is the interest in stress erupting in the academic community - among students, faculty and administrators. The authors present a reflection paper focused on student stress. In this paper, they first examine McLean 's model of context, vulnerability and stressors. This model provides the framework for the student surveys and for the entire paper. Based on the students surveys, an assessment is made of how asma" group of students are coping with stress. The paper fina"y suggests what can be done by students, faculty, and administrators to insta" and/or improve social support systems that might reduce the harmful eftects of stress on students and thus impact the quality of education.

Estudo descritivo do suicídio no município de São Paulo (Brasil) - 1959 a 1968

Foi feito estudo epidemiológico retrospectivo descritivo de mortalidade por suicídio no município de São Paulo, Brasil, baseado nos dados oficiais. Foram estudadas as tendências de alguns caracteres epidemiológicos dessa causa de morte nos anos de 1959 a 1968: causas exógena, distribuição cronológica, distribuição causal e distribuição por sexo e idade.

Aspectos epidemiológicos da meningite meningocócica no município de São Paulo (Brasil), no período de 1968 a 1974

Estudo epidemiológico da meningite meningocócica no município de São Paulo no período de janeiro de 1968 a junho de 1974. A partir de julho de 1971 uma epidemia causada pelo meningococo sorogrupo C ocorreu na área. Em abril de 1974 foi observado o início de uma segunda epidemia determinada pelo meningococo sorogrupo A. Os maiores coeficientes de morbidade durante o período estudado ocorreram: nos meses frios; nos distritos sanitários da periferia do município; no grupo etário de 0 a 4 anos, no sexo masculino. No primeiro mês das duas epidemias diferiu significantemente o grupo etário mais atingido. A letalidade decresceu de 15,0% em 1968-1970 para 7,9% em 1971-1974. Ela apresentou, durante o período epidêmico, uma variação sazonal no sentido inverso ao da morbidade.

Qualidade protéica de dietas avaliadas segundo os padrões FAO 1968 e FAO 1973

Foi avaliada segundo "score" químico e aminoácido limitante, a qualidade protéica de 1.310 dietas consumidas no período de 24 horas, por famílias residentes em 18 localidades do Estado de São Paulo, Brasil. Foram utilizados os padrões de referência propostos pela FAO, em 1968 e em 1973. A totalidade das dietas apresentaram "score" inferior a 80 (padrão 1968). Pelo padrão 1973, em 93,4% das dietas o "score" foi superior a 80, sendo que 33,4% delas foi acima de 100. Os dois padrões apontam os aminoácidos sulfurados como os mais freqüentes limitantes da síntese protéica; 59% das dietas têm metionina como o primeiro aminoácido limitante (padrão 1968). Em 49,1% das dietas que apresentaram aminoácido limitante pelo padrão 1973, este é representado pelos aminoácidos sulfurados. Os resultados obtidos considerando o padrão FAO 1973 sugerem que a qualidade aminoacídica das dietas estudadas é satisfatória e que, se houver uma deficiência protéica, esta, provavelmente, corre por conta da ingestão insuficiente de proteínas e/ou energia.

Levantamento epidemiológico e virológico de casos suspeitos de poliomielite no Hospital Estadual Jesus, no período de janeiro de 1967 a março de 1968

Os autores apresentam os resultados de isolamento de poliovírus de crianças com suspeita de poliomielite paralítica no Isolamento do Hospital Estadual Jesus do Estado da Guanabara. Nas 188 amostras computadas apresentaram-se 79 positivas, destas 73,5% de poliovírus tipo I, 25,3% do tipo II e 1,2% do tipo III. Os autores mostram no Gráfico 1, um aumento da incidência da poliomielite a partir dos últimos meses no ano de 1967. Chamam a atenção para o grande número de casos no grupo etário de 0-3 anos (Gráfico 2); colocam ainda em questão o melhor equacionamento do problema das vacinações (Tabela 1), com estudos laboratoriais de avaliação da vacina Sabin. O estudo da procedência e sexo das crianças não permitiu maiores conclusões, sendo levantada também a relação da idade com a incidência da poliomielite (Tabela 2), bem como a necessidade de se realizar estudos para outros enterovírus, presentes na população infantil da área estudada.

Incindência de Himenolepíase nana e Taenia sp. no Instituto de Medicina Tropical da U. F. Pernambuco no período de 1968 a 1970

Os Autores realizando um levantamento coproparasitológico no Instituto de Medicina Tropical da U.F.Pe., com relação a incidência de Hymenolepis nana e Taenia sp no período de 1968 a 1970, encontram índice de infestação muito baixo, em tôrno de 0,05% a 2,7% para Taenia sp e 0,36% para Hymenolepis nana.

Training-related accidents during teacher-student-assistance activities of medical students

A survey was done to determine the most common hospital accidents with biologically contaminated material among students at the Medical College of the Federal University of Minas Gerais. Six hundred and ninety-four students (between fifth and twelfth semesters of the college course) answered the questionnaire individually. Three-hundred and forty-nine accidents were reported. The accident rate was found to be 33.9% in the third semester of the course, and increased over time, reaching 52.3% in the last semester. Sixty-three percent of the accidents were needlestick or sharp object injuries; 18.3% mucous membrane exposure; 16.6% were on the skin, and 1.7% were simultaneously on the skin and mucous membrane exposure. The contaminating substances were: blood (88.3%), vaginal secretion (1.7%), and others (9.1%). The parts of the body most frequently affected were: hands (67%), eyes (18.9%), mouth (1.7%), and others (6.3%). The procedures being performed when the accidents occurred were: suture (34.1%), applying anesthesia (16.6%), assisting surgery (8.9%), disposing of needles (8.6%), assisting delivery (6.3%), and others (25.9%). Forty-nine percent of those involved reported the accident to the accident control department. Of these 29.2% did not receive adequate medical assistance. Eight percent of those involved used antiretroviral drugs and of these 86% discontinued the treatment on receiving the Elisa method applied to the patient (HIV-negative); 6.4% discontinued the treatment due to its side-effects; and 16% completed the treatment.

Epidemiological aspects of schistosomiasis in workers of the Movement of Landless Rural Workers

Introduction Schistosomiasis is endemic in 74 countries and is considered a serious public health problem in some locations. Methods A transverse study was performed of 13 landless settlements in southern Sergipe from February to December 2009. The study included 822 settlers, of whom 601 underwent stool testing. Results The prevalence of schistosomiasis in landless workers was 4.3%. The population has a low education level, and basic sanitation services are not available to all residents. Conclusions The prevalence of schistosomiasis was low in the population and among different settlements, possibly because of different forms of water use by the settlers.

Assessment of medical courses in Brazil using student-completed questionnaires. Is it reliable?

INTRODUCTION: Debates about the quality of medical education have become more evident in the recent past, and as a result several different assessment methods have been refined for that purpose. The use of questionnaires filled out by medical students to assess the quality of lectures is one of the most common methods employed in our milieu. However, the reliability of this investigation method has not yet been systematically tested. The authors present the reliability of a specific form applied to the fourth grade medical students during the clinical psychiatry course. METHOD: Eighty-one fourth grade medical students were instructed to complete a form immediately after each clinical psychiatry lecture. Thirty-four students (42%) failed to turn in the forms after the final lecture. These students were given an identical form to assess the lectures in a retrospective fashion. The grades given by both groups of students for each performed lecture and the number of students who have graded an unperformed lecture were compared. Statistical significance for both groups was determined by means of the chi-square test (p< 0.05). RESULTS: Eighteen out of the 34 students who filled out the forms retrospectively (53%) rated the unperformed lecture, whereas only 5 out of the 47 students who filled out the forms during the course (11%) did so. This is statistically significant (p< 0.05). There was no statistical difference for the grades given to the lectures that were actually performed. DISCUSSION: The authors concluded the low reliability rate of the retrospective evaluation warrant a continuous assessment method during the course.

Sombreamento dos cafezais V: resultados de mais dois bienios: 1967/1968 - 1970/1971

Os dados obtidos durante os anos de 1967 a 1971 (2 biênios: 1967/1968 e 1670/1971) no cafèzal da E.S.A. "Luiz de Queiroz", parte sombreada e parte a pleno sol, foram estudados no presente trabalho, complementando aqueles de sete biênios já descritos em trabalhos anteriores. Os resultados obtidos, analisados estatisticamente em relação à produção, porcentagem de broca, porcentagem de frutos verdes, de maduros e de sêcos, rendimento de café da roça, relação café beneficiado/café coco e peneira média, permitiram as conclusões seguintes, principalmente em relação aos biênios estudados: a. o lote sombreado, em relação a um dos lotes não sombreado, apresentou diferenças significativas quanto à produção, em favor para o sombreado; isso se deve provavelmente ao fato de as plantas de sombra estarem agora em decadência com muitas árvores mortas, favorecendo o lote sombreado pela luz e pela matéria orgânica acumulada; b. a porcentagem de broca continuou a ser, em geral, sempre maior nos lotes sombreados; c. as porcentagens de frutos verdes, de maduros e de sêcos dependem, em geral, do ano e da época da colheita.