Initial stage of atherosclerosis in aorta of rabbits by administering cholesterol

Para obtener un modelo experimental de ateroesclerosis aórtica, se suministraron tres dosis de colesterol dietético (0,62; 0,93 y 1,24 g/día) durante 60 días a conejos neozelandeses machos adultos. Se evaluaron los niveles séricos de colesterol, colesterol-HDL y LDL, aspartato aminotransferasa (AST) y alanin aminotransferasa (ALT), así como el desarrollo de ateroesclerosis en aorta. El incremento en la dosis de 0,62 a 0,93 g/día de colesterol ocasionó un aumento significativo (p≤0,05) en la colesterolemia (de 6,79 ±2,34 a 9,51 ±0,10 g/l), principalmente por incremento del colesterol-LDL. La dosis de 1,24 g/día no indujo aumento adicional de la colesterolemia comparado con la dosis de 0,93 g/ día. La colesterolemia fue muy variable entre los conejos que recibieron 0,62 g/día; las dosis mayores de colesterol redujeron esta variabilidad. Las actividades ALT y AST permanecieron normales hasta el día 30 de la experiencia, incrementándose significativamente en el día 60 (p≤0,05) en los grupos que recibieron 0,93 y 1,24 g/día, asociadas a degeneración grasa hepática. Las tres dosis de colesterol indujeron áreas sudanofílicas de extensión variable en aorta. Las lesiones en aorta se caracterizaron por un incremento focal del espesor intimal causado por la infiltración de macrófagos espumosos y músculo liso, entremezclados en proporción variable con depósitos de matriz extracelular. En conclusión, se confirma la sensibilidad del conejo neozelandés a desarrollar hipercolesterolemia y lesiones ateroescleróticas en un corto período de tiempo con una dieta rica en colesterol. La dosis de 0,93 g/día durante 60 días fue la que indujo una respuesta hipercolesterolémica con menor variabilidad entre los conejos y lesiones ateroescleróticas bien desarrolladas. El modelo experimental de ateroesclerosis temprana permitirá estudiar el efecto ateroprotector de diferentes medicamentos y alimentos funcionales.To obtain an experimental model of aortic atherosclerosis, male adult New Zealand rabbits were fed with three doses of dietary cholesterol (0.62, 0.93 and 1.24 g/day) for 60 days. Serum cholesterol, HDL and LDL-cholesterol, aspartate aminotransferase (AST), alanin aminotransferase (ALT) and the development of atherosclerosis in aorta, were evaluated. Increased dietary cholesterol from 0.62 to 0.93 g/day resulted in a significant increase (p≤0.05) in serum cholesterol (from 6.79 ±2.34 to 9.51 ±0.10 g/l), due mainly to the increase in LDL-cholesterol. The dose of 1.24 g/day did not induce further increase in cholesterolemia compared to the dose of 0.93 g/day. Serum cholesterol was highly variable among rabbits that received 0.62 g/day, this variability was reduced with the highest dose of cholesterol. ALT and AST activities remained normal until day 30 of experience, increasing significantly at day 60 (p≤0.05) in the groups receiving cholesterol at the doses of 0.93 and 1.24 g/day, associated with liver fatty degeneration. All doses of cholesterol induced aortic sudanophilic lesion areas of variable surface. Aortic lesions were characterized by a focal increase in intima thickening caused by infiltration of foamy macrophages and smooth muscle mixed in variable proportions with extracellular matrix deposition. In conclusion, the sensitivity of the New Zealand rabbit to develop hypercholesterolemia and atherosclerotic lesions in a short period of time when consuming a high cholesterol diet, is confirmed. The dose of 0.93 g/day for 60 days caused a lower variability in the hypercholesterolemic response among rabbits with significant development of atherosclerotic lesions. This model of early atherosclerosis will allow the study of the atheroprotective effects of different medicines and functional foods.Fil: Lértora, W. J.. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias; ArgentinaFil: Billordo, G. I.. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias; ArgentinaFil: Mussart, Norma Beatriz. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Catugno, M. S.. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias; ArgentinaFil: Sanchez Negrette, M.. Universidad Nacional del Nordeste. Facultad de Cs.veterinarias; Argentin

Fatty Acids in the Meat of Buffaloes Supplemented with Fish Oil

The purpose of this study has been to investigate the influence of both a supplementary fish oil diet on conjugated linoleic acid (CLA) and n6 and n3 fatty acids on intramuscular fat in Mediterranean buffalo meat. Twenty animals were randomly divided into two groups and fed with Brachiaria brizantha, 3Kg rice bran, 500 g corn and 500 g sunflower pellets for 60 days. Group I received this diet only while in group II each animal received additional 100 ml fish oil daily. Results indicated a significant decrease of palmitic fatty acid in group II (232.67 mg/g fat) in relation to group I (254.73 mg/g fat). Among unsaturated acids (AGI), the 9c 11t CLA value of group II (21.23 mg/g fat) showed an increase in relation to group I (15.80 mg/g fat), while the linoleic acid content of group II (28,85 mg/g fat) decreased significantly in relation to group I (47,00 mg/g fat). However, the alpha linolenic acid showed no significant difference between the supplemented diet group and the control group (10.31 and 10.70 mg/g fat, respectively). Group II n6/n3 ratio was narrower (2.69:1) than that of group I (4.55:1). Summing up, group II diet, which included fish oil, increased the CLA content in intramuscular fat and decreased the n6 fatty acids, improving the n6/n3 ratio

High Throughput Selection of Effective Serodiagnostics for Trypanosoma cruzi infection

The diagnosis of Trypanosoma cruzi infection (the cause of human Chagas disease) is difficult because the symptoms of the infection are often absent or non-specific, and because the parasites themselves are usually below the level of detection in the infected subjects. Therefore, diagnosis generally depends on the measurement of T. cruzi–specific antibodies produced in response to the infection. However, current methods to detect anti–T. cruzi antibodies are relatively poor. In this study, we have conducted a broad screen of >400 T. cruzi proteins to identify those proteins which are best able to detect anti–T. cruzi antibodies. Using a set of proteins selected by this screen, we were able to detect 100% of >100 confirmed positive human cases of T. cruzi infection, as well as suspect cases that were negative using existing tests. This protein panel was also able to detect apparent changes in infection status following drug treatment of individuals with chronic T. cruzi infection. The results of this study should allow for significant improvements in the detection of T. cruzi infection and better screening methods to avoid blood transfusion–related transmission of the infection, and offer a crucial tool for determining the success or failure of drug treatment and other intervention strategies to limit the impact of Chagas disease

Epidemiology and pathogenesis of maternal-fetal transmission of Trypanosoma cruzi and a case for vaccine development against congenital Chagas disease

Trypanos o ma cruzi (T. cruzi or Tc) is the causative agent of Chagas disease (CD). It is common for patients to suffer from non-specific symptoms or be clinically asymptomatic with acute and chronic conditions acquired through various routes of transmission. The expecting women and their fetuses are vulnerable to congenital transmission of Tc. Pregnant women face formidable health challenges because the frontline antiparasitic drugs, benznidazole and nifurtimox, are contraindicated during pregnancy. However, it is worthwhile to highlight that newborns can be cured if they are diagnosed and given treatment in a timely manner. In this review, we discuss the pathogenesis of maternal-fetal transmission of Tc and provide a justification for the investment in the development of vaccines against congenital CD.Fil: Rios, Lizette. University of Texas Medical Branch; Estados UnidosFil: Campos, Emiliano Emanuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Menon, Ramkumar. University of Texas Medical Branch; Estados UnidosFil: Zago, María Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Garg, Nisha J.. University of Texas Medical Branch; Estados Unido

Liver response to low-hexachlorobenzene exposure in protein- or energy-restricted rats

The individual effects of protein deficiency and energy restriction on liver response to low-hexachlorobenzene (HCB) exposure were investigated in adult male Wistar rats. In rats fed either the low-protein or control diet, the only effect caused by HCB was a decrease in paralysis time following an ip injection of zoxazolamine. This decrease was similar for both groups. In the animals subjected to energy restriction, HCB induced a greater decrease in paralysis time, an increase in the size of centrilobular hepatocytes, a lower liver DNA content and an increased concentration of HCB in the adipose tissue, compared with the control and protein-deficient groups. Our data suggest that energy restriction increases liver response to HCB, while protein deficiency does not impair the hepatic reaction to small doses of HCB exposure

Milk fatty acid profile from grazing buffaloes fed a blend of soybean and linseed oils

The aim of the study was to examine the changes in milk fatty acid (FA) profile of grazing buffaloes fed either low (L, 276g/d) or high (H, 572g/d) doses of a blend (70:30, wt/wt) of soybean and linseed oils. Fourteen multiparous Mediterranean buffaloes grazing on a native pasture were fed 4 kg/day of a commercial concentrate containing no supplemental oil over a pre-experimental period of ten days. The baseline milk production and composition and milk FA profile were measured over the last three days. After this pre-experimental period the animals received the same concentrate added with either the L or H oil doses for 26 additional days. Milk yield (g/animal/day) did not differ at the start (1776 ± 522 and 1662 ± 291 for L and H, respectively, P<0.622) or at the end of the trial (4590 ± 991 and 4847 ± 447 in L and H, respectively, P<0.543). Baseline milk fat content (g/kg) averaged 77.1 (±20.5) in L and 74.3 (±9.9) in H (P<0.10) and was reduced (P<0.031) to 60.7 (±23.6) and 49.4 (±11.2) (P<0.0031) respectively after L and H with no differences between treatments (P<0.277). Baseline milk protein content (L=43.2 ± 3.4 and H= 44.3 ± 6.9g/kg) increased after oil supplementation (P<0.0001) in both L (73.2 ± 6.0g/kg) and H (68.4 ± 4.9g/kg) without differences between oil doses (P<0.123). Milk fat content of 14:0 decreased after oil supplementation only in the H treatment (5.29 to 4.03, P<0.007) whereas that of 16:0 was reduced (P<0.001) at both L (24.49 to 19.75g/100g FA) and H (25.92 to 19.17g/100g FA) doses. The reduction of total content of 12:0 to 16:0 was higher (P<0.052) in H (32.02 to 23.93g/100g FA) than L (30.17 to 25.45g/100g FA). Vaccenic acid content increased (P<0.001) from 5.70 to 13.24g/100g FA in L and from 5.25 to 16.77 in H, with higher results in the in H treatment (P<0.001). Baseline rumenic acid was sharply increased (P<0.001) in L (1.80 to 4.09g/100g FA, +127%) and H (1.60 to 4.61g/100g FA, +187%) with no differences between L and H (P<0.19). Overall, these results indicate a pronounced improvement in the nutritional value of milk fat from grazing buffaloes fed little amounts (0.276g/day) of a blend of soybean and linseed oils

Prevalência da doença de Chagas em gestantes da região sul do Rio Grande do Sul Prevalence of Chagas disease among pregnant women in the southern region of Rio Grande do Sul

Anticorpos antiTrypanosoma cruzi no cordão umbilical de 351 parturientes da Cidade de Pelotas, RS foram pesquisados a fim de investigar a prevalência da doença de Chagas em gestantes. Um (0,3%) caso foi identificado, não sendo detectada transmissão congênita. Salienta-se a importância da investigação da doença de Chagas em gestantes de zonas endêmicas ou provenientes destas.<br>Anti-Trypanosoma cruzi antibodies in the umbilical cord of 351 parturients in the city of Pelotas, Rio Grande do Sul were investigated to determine the prevalence of Chagas disease among pregnant women. One case was identified (0.3%), without detection of congenital transmission. This highlights the importance of investigating Chagas disease among pregnant women living in or originating from endemic areas