[Plasma cell tumors associated with HIV infection].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to A Gil.
Explore the source record for details and available documents.
Liver cirrhosis has been induced with thioacetamide administered via different routes in rats and other species. The oral intake of thioacetamide causes nodular liver cirrhosis in rats characterized by extensive fibrosis occupying most of the hepatic parenchyma. To characterize the cytological features of cirrhosis induced by thioacetamide, and the degree of recovery obtained with dietary nucleotides, we made a morphometric study of the hepatocytes in rats administered 300 mg/l of thioacetamide for 4 months, and in rats receiving the same hepatotoxic treatment but allowed a 2-weeks recovery period on a nucleotide-free diet or a 250 mg/100 g nucleotide-supplemented diet. Thioacetamide caused to cell damage and affected the ultrastructure of hepatocytes leading to a decrease in cytoplasmic area together with increased nuclear and nucleolar size. Dietary supplementation with nucleotides favoured recovery, restoring the cytoplasmic (TN=491.7+/-9.6 vs TAA=305.1+/-3.7), nuclear (73.6+/-2.8 vs 97.4+/-2.9), and nucleolar area of damaged hepatocytes (5.6+/-0.3 vs 14.0+/-0.9). The injury from thioacetamide intake increased liver collagen, but dietary nucleotides prevented hepatic deposition of this protein. This study supports the hypothesis that dietary supplementation with nucleotides is decisive in ensuring hepatocyte recovery after thioacetamide-induced liver damage, and that dietary nucleotides have antifibrotic properties.
The aim of this cross-sectional study was to assess the seroprevalence of antibodies against varicella zoster (VZV), herpes simplex type 1 (HSV-1) and type 2 (HSV-2), hepatitis B (HBV) and hepatitis A (HAV) viruses in adolescents (14-17 years of age) in Madrid, Spain. At the study visit, demographic data and blood samples were obtained. The enzyme linked immunosorbent assay (ELISA) method was used to assess the presence of anti-VZV, anti-HSV-1, anti-HSV-2, anti-HBc and anti-HAV antibodies. A total of 1191 serum samples were collected. Mean age (SD) and male/female ratio of the study population were 15.3 (1.1) years and 0.9, respectively. Seroprevalences obtained were as follows: anti-VZV (94%), anti-HSV-1 (46%), anti-HSV-2 (5%), anti-HBc (3%) and anti-HAV (5%). These data show that Spanish adolescents should be considered a target group for prevention programmes against HSV-2, HBV and HAV infections.
BACKGROUND/AIMS: Dietary nucleotides modulate a number of metabolic processes, including long-chain polyunsaturated fatty acid metabolism. In this study, we evaluated the effect of dietary nucleotides on plasma and liver microsomal fatty acid profiles in a rat model of liver cirrhosis induced by oral intake of thioacetamide. METHODS: Fifty-four female Wistar rats were assigned to one of the following groups: rats in the thioacetamide group (n=45) were given 300 mg thioacetamide/l in their drinking water for 4 months, and rats in the control group (n=9) received water during the same period. After 4 months of treatment, 9 rats in each group were killed. The remaining rats in the thioacetamide group were divided into two new groups, and the animals in each were allowed to recover for 1 or 2 weeks on either a nucleotide-free diet or the same diet supplemented with 50 mg of each of the following: AMP, GMP, CMP, IMP and UMP per 100 g diet. RESULTS: Saturated (mainly stearic acid), monounsaturated, and n-6 long-chain polyunsaturated fatty acids (mainly arachidonic acid), and also the unsaturation index decreased in plasma of rats with experimental cirrhosis. Administration of the diet supplemented with nucleotides to thioacetamide-treated rats corrected plasma levels of saturated, n-6 long-chain polyunsaturated fatty acids and the unsaturation index. In liver microsomes, the cirrhotic rats showed lower levels of protein and higher levels of palmitic, oleic, linoleic and arachidonic acids. Protein concentrations and levels of all the above-mentioned fatty acids were corrected with the nucleotide-enriched diet. CONCLUSIONS: Dietary nucleotides contribute to correcting plasma and liver microsomal fatty acid alterations in rats with liver cirrhosis induced by chronic oral administration of thioacetamide.
The goal of this study was to evaluate the influence of severe protein-energy malnutrition (PEM) on lipid composition and fatty acid profile in the small intestinal mucosa of lactating pigs. Malnutrition was achieved by 80% protein-energy restriction for 30 d (20% of the food intake in the control group) in 7-d-old newborn piglets. Malnourished piglets had significantly lower concentrations of cholesterol, phospholipid and triglycerides in the jejunum and ileum compared with freely fed controls. Fatty acid composition of the intestinal mucosa was severely affected by malnutrition. A sharp decline in the relative percentages of (n-3) and (n-6) long-chain polyunsaturated fatty acids (LC-PUFA) in malnourished piglets paralleled higher (n-9) fatty acid proportions in the total mucosa, microsomes and phospholipids of the jejunum. The structure of the small intestine was severely affected as assessed by light and electron microscopy, and alkaline phosphatase and disaccharidase activities in the intestinal mucosa were also significantly impaired. Plasma from malnourished piglets had significantly lower concentrations of (n-3) and (n-6) LC-PUFA than that of control piglets; however, the fatty acid composition of red blood cell membrane was unaffected. Our results suggest that early severe PEM dramatically modifies intestinal membrane lipid composition. Changes in the lipid composition of the small intestinal mucosa and in phospholipid distribution as well as in the fatty acid profile may alter membrane fluidity and organization. These alterations appear to affect the activity of membrane-bound hydrolytic enzymes.
The human milk composition may be influenced by several factors, such as gestational age or genetic characteristics and dietary habits of different populations. To analyze the total lipid and fatty acid contents of human milk, we have conducted two studies, one on mothers who had delivered preterm and term newborns and another on mothers from two different sociocultural backgrounds (Spain and Panama). The total lipid content (g/100 g wet weight) was significantly higher in term (2.76 +/- 0.66; mean +/- SD) than in preterm mature milk (1.06 +/- 0.4). The relative amount of 18:1n-9 was significantly higher in preterm than in term milk for transitional and mature milk, whereas that for the colostrum followed the opposite trend. Concerning the comparison between milk from mothers born in different countries, the relative contents of each of the fatty acids 16:0, 16:1n-7, 18:2n-6, 18:3n-3, and 22:5n-3 were higher in Panamanian than in Spanish milk, whereas the mean percentages of saturated fatty acids < 14:0, of 16:1n-9, and of 18:1n-9 were higher in Spanish than in Panamanian milk. Statistically significant differences were found during the three periods of lactation considered for almost all the fatty acids mentioned above, especially for 18:1n-9 and 18:3n-3. Although the potential biological significance of the changes in oleic acid content between preterm and term milk remains unclear, differences in fatty acid content between Spanish and Panamanian milk reflect the different composition of the diet among women from these countries.
Explore the source record for details and available documents.
The development of the atherosclerosis is mediated by the accumulation of oxidized lipids in the arterial wall. There is a relationship between average intake of dietary fat, its quality, and incidence of atherosclerosis. The goal of this work was to study the effect of different dietary fats on the coenzyme Q10 and hydroperoxide content of liver mitochondria in rabbits affected by an induced atherosclerosis. The results show that the induction of experimental atherosclerosis leads to a significant increase in hydroperoxides of rabbit liver membrane mitochondria and to a significant drop in the content of CoQ10. Furthermore, treatment of atherosclerotic rabbits with different diets resulted in an increase of membrane hydroperoxides in the group fed sunflower oil whereas the increase was significantly lower for animals fed virgin olive oil and fish oil stabilized with vitamin E (1 g/kg). CoQ10 levels only recovered partially in all groups; however, values in the sunflower oil were significantly lower as compared to corresponding values of the other groups. The use of either virgin olive oil or vitamin E stabilized fish oil in the dietary treatment of atherosclerosis appears to be a valid alternative for maintaining adequate levels of CoQ10 and hydroperoxides in liver mitochondria.
The activity of UDP-N-acetylglucosamine 2-epimerase was determined in the liver of rats and guinea-pigs of different ages. The activity of this enzyme in rats was low at birth, increased to a maximum value on day 15, and fell gradually until day 30. Thereafter, it increased up to the 60th day. The activity profile of the enzyme from guinea-pig liver was very similar. However, guinea-pig activity was 2-5 times lower than in rats. Both rats and guinea-pigs displayed similar liver sialic acid contents which increased from birth to 2 months of age. Rats also showed a N-glycolylneuraminic acid content that decreased from birth to 2 months. From these results we can inferred that postnatal UDP-N-acetylglucosamine 2-epimerase activity seems to be correlated with age and the developmental states of rats and guinea-pigs.
Explore the source record for details and available documents.
Diluted dried blood drops on filter paper were compared with serum samples as a specimen source for qualitative anti-HAV antibody determination by ELISA. A total of 298 serum samples and dried blood drops were collected from a population of healthy adolescents (15.3 +/- 1.2 years old). The prevalence of anti-HAV antibody obtained by testing serum samples was 7.7% (95% CI:4.8 10.1). Compared with serum sampling the sensitivity and specificity of diluted dried blood drops were 91.3 and 99.3%. The positive and negative predictive values were 91.3 and 99.3%, respectively, and the likelihood ratios of positive and negative results were 91 and 0.09. It is proposed that this test represents a reliable procedure for anti-HAV antibody testing.
A two-stage cross-sectional study was conducted in a 951-bed acute-care hospital: a first survey designed to determine the profile of patients aged > or = 64 years needing supportive social/health care services, in which 38 patients discharged between June and July, 1992 (group 1) with social/health care problems that accounted for inappropriate hospitalization days participated, and a second survey designed to identify patients aged > or = 65 years at high risk and thus facilitating the early intervention of social workers, in which 153 patients selected at random and interviewed between August and September, 1992 (group 2) participated. A significantly higher percentage of group 1 patients had no medical insurance, were admitted to hospital for treatment, lived alone, had been readmitted in the previous 6 months, suffered from dementia and/or cognitive impairment, presented with associated chronic illnesses, and showed lower Barthel index scores as compared to group 2 patients. In patients in group 2, hospital discharge was delayed due to the need of supportive social and health care services in only 27 patients. The percentage of agreement in the suitability of the resource provided was higher after (92.6%) than before the intervention (71.1%). The mean number of inappropriate hospitalization days was 3.5 days for patients in group 1 and 1.9 days for those in group 2 (p = 0.013). The early identification of elderly inpatients at high risk of needing additional supportive social and health care would help patients to find the most appropriate resource according to their individuals needs.
We have assessed the effect of the oral ingestion of thioacetamide on small intestine structure and function. Thioacetamide-treated rats showed diminished mucosa weight; protein, DNA, and RNA content; and leucine aminopeptidase activity as compared to controls in both jejunum and ileum. In the jejunum, there was a reduction in the activities of alkaline phosphatase, ATPase, glucose-6-phosphatase, and myeloperoxidase, whereas in the ileum, maltase, lactase, and gamma-glutamyltranspeptidase were reduced. In both jejunum and ileum we found enlarged intercellular spaces, dark epithelial enterocytes, and lymphocyte infiltration. Enterocytes showed lobulated nuclei, deranged mitochondria with loss of their cristae, dilated rough endoplasmic reticulum containing dense material, and vesiculation of the smooth endoplasmic reticulum and the Golgi apparatus. Smooth muscle cells of the intestine exhibited ultrastructural alterations. These findings indicate that chronic oral intake of thioacetamide mimics not only hepatic alterations but also small intestine alterations normally associated with human cirrhosis.
The administration of thioacetamide in rats induces nodular cirrhosis of the liver, characterized by fibrous septae, parenchymal nodules, proliferation of the bile ducts, and excessive deposition of connective tissue elements. Nodular cirrhosis is also associated with changes in lipid metabolism, as shown by the accumulation of lipid droplets in the hepatocyte cytoplasm. Adequate nutritional support during cirrhosis is important to sustain liver function and promote recovery after the lesions have been induced. Supplementation with nucleotides may increase cellular proliferation and thus optimize hepatic recovery. The aim of this study was to investigate the effects of dietary nucleotide supplementation on the degree of fibrosis and steatosis in rats with liver cirrhosis induced by four months of oral intake of thioacetamide. The use of dietary nucleotides after thioacetamide administration was found to decrease the percentage area of fibrous septae. In animals with liver cirrhosis fed the nucleotide-supplemented diet for two weeks, the total area of fibrosis was reduced. Withdrawal of the hepatotoxic agent led to a decrease in the degree of steatosis in cirrhotic animals, which was significant in rats given the nucleotide-supplemented diet during a two-week recovery period. In conclusion, dietary nucleotides may be an important factor in the histological recovery of damaged liver in experimental cirrhosis.
We have addressed the question of whether dietary nucleotides contribute to the liver nucleic acid pool and whether this contribution is related to age. Two experiments were performed in rats of 1 months, 3 months and 17 months of age. In the first, rats were fed a nucleotide-free diet or the same diet, but supplemented with nucleotides for 3 and 10 days. In the second experiment, rats were starved for 3 days. Liver RNA decreased by 10-day deprivation of dietary nucleotides and starvation in young and adult rats but not in the old. Liver DNA decreased by starvation in adult and old rats but not in the young, whereas nucleotide deprivation had no effect. These results, demonstrating that dietary nucleotide deprivation causes an effect on liver RNA pool similar to the effect of starvation, indicate that dietary nucleotides contribute to the liver RNA pool, this influence being related to age.
The objective of this study was to evaluate the influence of dietary nucleotide supplementation in preterm infants during the first month of life on the intestinal permeability to lactulose, mannitol and to beta-lactoglobulin and on the development of circulating antibodies to beta-lactoglobulin and alpha-casein. Twenty-seven preterm infants were enrolled in the study; 11 of them were fed a standard low-birth weight milk formula and 16 infants were fed the same formula supplemented with nucleotides at similar levels to those found in human milk. Blood and urine samples were obtained at 1, 7 and 30 days of age. Serum beta-lactoglobulin, serum IgG antibody to alpha-casein and serum IgG antibody to beta-lactoglobulin were measured by ELISA. The lactulose/mannitol urinary excretion rate was measured by gas liquid chromatography. Neither the intestinal permeability to saccharides nor the intestinal absorption of beta-lactoglobulin were affected by the nucleotide supplementation. However, serum concentrations of IgG antibody to beta-lactoglobulin were higher in preterm neonates fed the supplemented formula than in those fed the standard formula. According to these results, dietary nucleotides might influence the maturation of the humoral immune response in preterm newborn infants.
Lead is a toxin widely used in industry. Recently, medical investigation into lead exposure has turned to testing organ systems, such as the immune system, that historically were not associated with lead poisoning. We evaluated the effects of doses of 13, 130 or 1,300 ppm of lead on the adherence of mouse peritoneal cells, and particularly on macrophages. Cellular adherence was measured according to the De la Fuente technique. Adherence of macrophages showed significant changes in the 1,300 ppm group, revealing a reduction to 55% of the control group. The macrophage adherence index showed 91% sensitivity and 96% specificity. These results indicate a considerable reduction in the adherence of peritoneal macrophages following exposure to certain levels of lead.
BACKGROUND AND METHODS: We used thioacetamide administered orally to induce cirrhosis in rats, and after these had recovered for 1 and 2 weeks we examined the effects of dietary supplementation with monounsaturated and n-3 polyunsaturated fatty acids, or with a combination of n-3 and n-6 polyunsaturated fatty acids, on the extent of steatosis and collagen content in the liver. RESULTS: Nodular cirrhosis, increased collagen content, and lipid accumulation were established after 4 months of treatment with thioacetamide. When the animals were fed a diet rich in oleic acid for 2 weeks, the steatosis and fibrosis decreased. Supplementation with n-3 polyunsaturated fatty acids favored reductions in collagen content but did not reduce the fat accumulation. With a diet supplemented with a mixture of n-3 and n-6 fatty acids we found no reduction in either lipid accumulation or collagen content. CONCLUSIONS: Fibrosis and steatosis may be influenced by dietary fat, and monounsaturated fat appears to influence favorably the histologic recovery of the damaged liver.