Controle de qualidade de técnicas realizadas nos laboratórios de parasitologia da Secretaria Municipal de Saúde do Município de Salvador, Bahia / Quality control of the parasitological techniques used in the laboratories of clinical

As infecções por enteroparasitos estão entre os mais freqüentes agravos infecciosos, estimando-se que o número de infectados no mundo seja de aproximadamente 3.5 bilhões de pessoas e no Brasil, 130 milhões de habitantes são acometidos por algumaespécie de parasito intestinal. Desta forma, métodos laboratoriais para diagnóstico dos agentes etiológicos das doenças parasitárias intestinais são de extrema relevância. O objetivo deste trabalho foi caracterizar o controle de qualidade interno nas fases do processopré-analítico, analítico e pós-analítico utilizado nos laboratórios de Análises Clínicas da Secretaria Municipal de Saúde de Salvador em 2008, comparando-o com resultados obtidos em 2005. Detectou-se precariedade quanto à padronização e execução das técnicas nos Laboratórios de Parasitologia da Secretária Municipal de Saúde de Salvador em 2005 e 2008, evidenciando um Programa deControle de Qualidade Interno ainda ineficaz ou inexistente.

Inhibition of rat microsomal lipid peroxidation by the oral administration of D002

The effect of D002, a defined mixture of higher primary alcohols purified from bee wax, on in vivo and in vitro lipid peroxidation was studied. The extent of lipid peroxidation was measured on the basis of the levels of thiobarbituric acid reactive substances (TBARS). When D002 (5-100 mg/kg body weight) was administered orally to rats for two weeks, a partial inhibition of the in vitro enzymatic and non-enzymatic lipid peroxidation was observed in liver and brain microsomes. Maximal protection (46 percent) occurred at a dose of 25 mg/kg. D002 behaved differently depending on both the presence of NADPH and the integrity of liver microsomes, which suggests that under conditions where microsomal metabolism was favored the protective effect of D002 was increased. D002 (25 mg/kg) also completely inhibited carbon tetrachloride- and toluene-induced in vivo lipid peroxidation in liver and brain. Also, D002 significantly lowered in a dose-dependent manner the basal level of TBARS in liver (19-40 percent) and brain (28-44 percent) microsomes. We conclude that the oral administration of D002 (5, 25 and 100 mg/kg) for two weeks protected rat liver and brain microsomes against microsomal lipid peroxidation in vitro and in vivo. Thus, D002 could be useful as a dietary natural antioxidant supplement. More studies are required before these data can be extrapolated to the recommendation for the use of D002 as a dietary antioxidant supplement for humans

Central lead administration inhibits water intake and sodium appetite in rats

We have demonstrated that acute third ventricle injections of lead acetate (PbAc) exert a powerful antidipsogenic effect and induce a significant increase in renal sodium excretion. In the present study we confirm the antidipsogenic effect of lead and demonstrate that central administration of this metal, in minute amounts, significantly reduces salt intake both during dehydration and after central angiotensinergic stimulation. Adult male Wistar rats had the third ventricle cannulated seven days before the experiments. During this period they had free access to distilled water and hypertonic saline solution (1.5 percent). After a 24-h period of fluid deprivation, experimental animals received third ventricle injections of PbAc (0.3, N = 8 and 3.0 nmol/rat, N = 14) while controls received sodium acetate (NaAc; 3.0 nmol/rat, N = 10). Rats treated with PbAc at the highest dose showed a significant reduction both in water and hypertonic saline intake when compared to controls. When the effect of lead administration on angiotensin II-induced water and salt intake was studied, normohydrated animals received third ventricle injections of angiotensin II (9.6 nmol/rat) after pretreatment with 3.0 nmol/rat of PbAc (experimental group, N = 10) or NaAc (controls, N = 8). The group pretreated with PbAc presented a significant reduction in both water and salt intake compared to controls. Thus, this study confirms the antidipsogenic effect of central lead injections and demonstrates that the presence of lead in the brain exerts a significant inhibition of sodium appetite

Effect of policosanol on the hepatic cholesterol biosynthesis of normocholesterolemic rats

We have suggested previously, measuring 14C-acetate incorporation into free cholesterol, that oral administration of policosanol inhibits hepatic cholesterol biosynthesis in rats. Nevertheless, since acetate has limitations to study cholesterol synthesis in vivo, we now investigate rates of incorporation of labeled water into hepatic sterol after policosanol treatment. Absolute rates of incorporation of 3H-water in sterols were depressed by policosanol by about 20 percent, giving a more accurate degree of cholesterol biosynthesis inhibition in this species. Since policosanol did not inhibit labeled mevalonate incorporation into cholesterol in rat liver, we also studied the effect of policosanol on hydroxy-methylglutaryl-coenzyme A (HMG-CoA) reductase. Reductase activity assayed in microsomes treated with policosanol remained unchanged, suggesting that cholesterol synthesis is not inhibited by a direct action of policosanol on this enzyme

Policosanol inhibits cholesterol biosynthesis and enhances low density lipoprotein processing in cultured human fibroblasts

Policosanol is a mixture of aliphatic primary alcohols isolated and purified from sugar cane wax, that induces cholesterol-lowering effects in experimental models and human beings. When human lung fibroblasts were incubated with policosanol for 48 hours prior to the experiment, a dose dependent inhibition of 14C-acetate incorporation into total cholesterol was observed, whereas labeled mevalonate incorporation was not inhibited. Even when cholesterol synthesis was not strongly inhibited, low density lipoprotein (LDL) processing was markedly enhanced. Thus, LDL binding, internalization and degradation were significantly increased after policosanol treatment. In addition, despite the fact that'cholesterol generation was not inhibited at the lowest dose of policosanol assayed, LDL processing was significantly increased. The current data indicate that policosanol inhibits cholesterol synthesis at the earliest steps of the cholesterol biosynthetic pathway. On the other hand, this study suggests that the increase in LDL processing may be partially explained by the inhibition of cholesterol biosynthesis, even though an sterol-independent mechanism might be responsible for the enhancement of LDL-receptor activity

Estudio del efecto sobre lípidos y lipoproteínas séricos y de la tolerancia al tratamiento oral con dosis crecientes de policosanol en monos macaca arctoides / Study of effect of oral treatment with increased dosis of policosanol on serum an lipoproteins macaca arctoides mankeys

En diferentes modelos experimentales se ha demostrado que el Policosanol reduce los niveles séricos de colesterol. En el presente trabajo se investiga el efecto del tratamiento oral con dosis sucesivas crecientes de Policosanol sobre los lípidos y las lipoproteínas séricos de monos de la especie Macaca arctoides, así como la tolerancia a este tratamiento. Dosis de 50, 150, 300, 400 y 500 mg/kg de Policosanol se administraron a 4 animales adultos por períodos de 10 días. Los valores séricos de los lípidos y lipoproteínas se determinaron antes de iniciar el tratamiento, al finalizar la administración de cada dosis y a los 15, 30 y 45 días del período de lavado. De igual forma se cuantificaron los parametros de hematología y bioquímica sanguínea investigados. Además, se controló sistemáticamente el estado físico de los animales, su peso corporal, así como su repertorio conductual para determinar si el tratamiento afectaba alguno de los parámetros conductuales habituales de esta especie o si aparecía algún signo de fármaco toxicidad. Mediante la décima de Freidman se compararon los valores de los diferentes períodos de tratamiento con los niveles basales, así como los del período de lavado con la última etapa de tratamiento. Los resultados sugieren que la administración oral de dosis sucesivamente crecientes de Policosanol producen un rápido y notable decremento de las cifras de colesterol y LDL-C en monos de la especie Macaca arctoides y que el tratamiento es bien tolerado por esta especie a dosis tan elavadas como 500 mg/kg de peso corporal