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This study deals with adherence to tuberculosis treatment among men and women as well as the disease's links and consequences vis-à-vis life styles and treatment outcomes. The ethnographic study was a component of the Tuberculosis Epidemiological Control Project in the city of Pelotas and aimed to identify the reasons patients failed to complete treatment. Direct ethnographic observations and semi-structured interviews were used. Use of the term "adherence" is justified by the concern for extending to other fundamental factors in addition to the patient's own individual responsibility. This approach fostered an understanding of views towards disease, social dynamics among the various protagonists involved in the disease process, and treatment. Some of the factors considered in adherence to treatment were: socio-demographic characteristics, cultural factors, popular beliefs, the cost-benefit relationship, physical and chemical aspects of the drugs, the physician-patient relationship, and level of family participation in treatment.  相似文献   
43.
Several techniques have been developed to assess the ecotoxicity of contaminated watercourses. Most of these techniques involve chemical alterations of water samples, by diluting it or by adding chelating agents. These changes become particularly severe when assessing the toxicity of samples with very low pH and with high quantities of contaminants. Trying to overcome this problem, a novel toxicity test, specific for acid waters, was previously developed and field validated. The toxicity of acid samples is assessed using the survival time of Ceriodaphnia dubia. During this study, the novel test was applied to a field situation, where an aquatic system is seriously impacted with acid mine drainage. Its efficiency was tested and compared with two classical toxicity tests: the Microtox and the median lethal dilution with C. dubia. The survival time test was performed without adjusting pH and after adjusting pH to a fixed value (pH 2, 3, and 4). At pH 2 and 4 no acceptable results were obtained; at pH 3 it was possible to distinguish the toxicity due to pH from the toxicity due to other toxicants. The test conducted at local pH was able to discriminate toxicity sources only for highly contaminated samples. The toxicity evaluation of acid mine drainage samples was possible neither with the median lethal dilution test nor with Microtox.  相似文献   
44.
In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two beta-carboline alkaloids, 4-methoxy-1-vinyl-beta-carboline (1) and 4,8-dimethoxy-l-vinyl-beta-carboline (2) have been isolated from the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed marked inhibitory activity of iNOS on LPS- and interferon-gamma-stimulated RAW 264.7 cells.  相似文献   
45.
We evaluated children in the first grade of a elementary school using neurological examination. With no previous knowledge of their educational performance, were invited all children attending five classes of the first grade of an elementary public school chosen randomly, in Itatiba / Sao Paulo / Brazil, whose parents assigned a Commitment Term for participation in this research. Children who missed three evaluations in different days or whose parents did not assigned the Commitment Term were excluded. The Traditional Neurological Examination (ENT) (Lefevre, 1972) was applied. It was considered for normal the measurement of the skull circumference, proposed by Diament & Rodrigues (1976), and the application of all ENT items. The data were stored in a database of the Epi6 Program (Epidemiologic Information), and analyzed by percentage calculation and by the chi2 test. The significance level was 0.05. Children evaluated were 124. The ENT results were normal in 87 (70.16%) and altered in 37 (29.83%). Among the alterations, there were observed: light tremor, light muscular hypotonia, speech acquisition delay, macrocephaly, microcephaly, hyperactivity, cranial nerve syndrome, central facial paralysis. One child presented corticospinal tract impairment syndrome of the distal lower extremities.  相似文献   
46.
Loxosceles adelaida spiders (Araneae, Sicariidae) are found near and inside the caves in the Parque Estadual Turistico do Alto Ribeira (PETAR), Sao Paulo, Brazil, which are visited by thousands of tourists every year. Several Loxosceles species are a public health problem in many regions of the world, by causing severe dermonecrosis and/or complement dependent haemolysis upon envenomation. The aim of this study was to characterize the biochemical and biological properties of L. adelaida venom and evaluate the toxic potential of envenomation by this non-synanthropic Loxosceles species. The biological activities of the L. adelaida venom was compared to that of Loxosceles gaucho, a synanthropic species of medical importance in Brazil. L. adelaida venom showed a similar potential to induce haemolysis, dermonecrosis and lethality as L. gaucho venom. L. adelaida crude venom was purified, yielding a 31 kDa component endowed with haemolytic and dermonecrotic activities. In conclusion, we show here that the troglophile Loxosceles species, L. adelaida, commonly found in the complex of caves from PETAR, is potentially able to cause envenomation with the same gravity of those produced by synanthropic species.  相似文献   
47.
The authors report a case of a virilizing adrenal tumor that developed in a 2-year-old child with Beckwith-Wiedemann syndrome (BWS). He had a fetal diagnosis of omphalocele and a history of neonatal adrenal cysts. The importance of prenatal diagnosis of BWS and postnatal follow-up of tumors is discussed. The differential diagnosis of adrenal pathologies occurring in BWS also is reviewed.  相似文献   
48.
Extracellular S100B protein modulates ERK in astrocyte cultures   总被引:3,自引:0,他引:3  
S100B is a calcium binding protein expressed and secreted by astrocytes. Extracellular S100B stimulates the proliferation of astroglial cells and the survival of neurons. Extracellular signal regulated kinases (ERK) are involved in the transduction of proliferating signals in astrocytes. Here we report that S100B significantly increases the activity of ERK in primary cultures of astrocytes, a result which may be related to previous observations of the effect of this protein on glial proliferation. We further confirm that conversion of S100B to its covalent dimer by oxidation of cysteine residues increases its extracellular activity. Although we cannot exclude S100B involvement in other mechanisms of signal transduction, these results suggest that ERK activity in astrocytes is modulated by extracellular S100B.  相似文献   
49.
The ability of aluminum to inhibit the (Na(+)/K(+))ATPase activity has been observed by several investigators. The (Na(+)/K(+))ATPase is characterized by a complex molecular heterogeneity that results from the expression and differential association of multiple isoforms of both catalytic (alpha) and regulatory (beta) subunits. For instance, three main alpha (alpha(1), alpha(2) and alpha(3)) and three beta (beta(1), beta(2) and beta(3)) subunit isoforms exist in vertebrate nervous tissue, whereas only alpha(1) and beta(1) have been identified in kidney. However, no studies have focused on determining the change in (Na(+)/K(+))ATPase isoforms caused by chronic exposure to aluminum and its relation with aluminum toxicity. In this study, adult male Wistar rats were submitted to chronic dietary AlCl(3) exposure (0.03 g/day of AlCl(3) for 4 months), and the activity and protein expression of (Na(+)/K(+))ATPase isozymes were studied in brain cortex synaptosomes and in kidney homogenates. The intracellular levels of adenine nucleotides, plasma membrane integrity, and aluminum accumulation were also studied in brain synaptosomes. Aluminum accumulation upon chronic dietary AlCl(3) administration significantly decreased the (Na(+)/K(+))ATPase activity measured in the presence of nonlimiting Mg-ATP concentrations, without compromising protein expression of alpha-subunit isoforms in brain and kidney. Aluminum-induced synaptosomal (Na(+)/K(+))ATPase inhibition was due to a reduction in the activity of isozymes containing alpha(1)-alpha(2) and alpha(3)-subunits. The onset of enzyme inhibition was accompanied by a decrease of the (Na(+)/K(+))ATPase sensitivity to submicromolar concentrations of ouabain, and it preceded major damage in plasma membrane integrity and energy supply, as revealed by the analysis of lactate dehydrogenase leakage and endogenous adenine nucleotides. The data suggest that, during chronic dietary exposure to AlCl(3), brain (Na(+)/K(+))ATPase activity drops, even if no significant alterations of catalytic subunit protein expression, cellular energy depletion, and changes in cell membrane integrity are observed. Implications regarding underlying mechanisms of aluminum neurotoxicity are discussed.  相似文献   
50.
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