Conjugated linoleic acid and cardiac health: Oxidative stress and energetic metabolism in standard and sucrose-rich diets

Studies on conjugated linoleic acid ingestion and its effect on cardiac tissue are necessary for the safe utilization of this compound as supplement for weight loss. Male Wistar 24-rats were divided into four groups (n = 6):(C)given standard chow, water and 0.5 ml saline, twice a week by gavage; (C-CLA)receiving standard chow, water and 0.5 ml of conjugated linoleic acid, twice a week, by gavage; (S)given standard chow, saline by gavage, and 30% sucrose in its drinking water; (S-CLA)receiving standard chow, 30% sucrose in its drinking water and conjugated linoleic acid. After 42 days of treatment S rats had obesity with increased abdominal-circumference, dyslipidemia, oxidative stress and myocardial lower citrate synthase(CS) and higher lactate dehydrogenase(LDH) activities than C. Conjugated linoleic acid had no effects on morphometric parameters in C-CLA, as compared to C, but normalized morphometric parameters comparing S-CLA with S. There was a negative correlation between abdominal adiposity and resting metabolic rate. Conjugated linoleic acid effect, enhancing fasting-VO2/surface area, postprandial-carbohydrate oxidation and serum lipid hydroperoxide resembled to that of the S group. Conjugated linoleic acid induced cardiac oxidative stress in both fed conditions, and triacylglycerol accumulation in S-CLA rats. Conjugated linoleic acid depressed myocardial LDH comparing C-CLA with C, and beta-hydroxyacyl-coenzyme-A dehydrogenase/CS ratio, comparing S-CLA with S. In conclusion, dietary conjugated linoleic acid supplementation for weight loss can have long-term effects on cardiac health. Conjugated linoleic acid, isomers c9, t11 and t10, c12 presented undesirable pro-oxidant effect and induced metabolic changes in cardiac tissue. Nevertheless, despite its effect on abdominal adiposity in sucrose-rich diet condition, conjugated linoleic acid may be disadvantageous because it can lead to oxidative stress and dyslipidemic profile. (c) 2007 Elsevier B.V All rights reserved.

Effect of saliva substitutes in combination with fluorides on remineralization of subsurface dentin lesions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Response to Treatment in a Prospective Cohort of Patients with Large Ulcerated Lesions Suspected to Be Buruli Ulcer (Mycobacterium ulcerans Disease)

Background: The World Health Organization (WHO) advises treatment of Mycobacterium ulcerans disease, also called Buruli ulcer'' (BU), with a combination of the antibiotics rifampicin and streptomycin (R+S), whether followed by surgery or not. In endemic areas, a clinical case definition is recommended. We evaluated the effectiveness of this strategy in a series of patients with large ulcers of >= 10 cm in longest diameter in a rural health zone of the Democratic Republic of Congo (DRC).Methods: A cohort of 92 patients with large ulcerated lesions suspected to be BU was enrolled between October 2006 and September 2007 and treated according to WHO recommendations. The following microbiologic data were obtained: Ziehl-Neelsen (ZN) stained smear, culture and PCR. Histopathology was performed on a sub-sample. Directly observed treatment with R+S was administered daily for 12 weeks and surgery was performed after 4 weeks. Patients were followed up for two years after treatment.Findings: Out of 92 treated patients, 61 tested positive for M. ulcerans by PCR. PCR negative patients had better clinical improvement than PCR positive patients after 4 weeks of antibiotics (54.8% versus 14.8%). For PCR positive patients, the outcome after 4 weeks of antibiotic treatment was related to the ZN positivity at the start. Deterioration of the ulcers was observed in 87.8% (36/41) of the ZN positive and in 12.2% (5/41) of the ZN negative patients. Deterioration due to paradoxical reaction seemed unlikely. After surgery and an additional 8 weeks of antibiotics, 98.4% of PCR positive patients and 83.3% of PCR negative patients were considered cured. The overall recurrence rate was very low (1.1%).Interpretation: Positive predictive value of the WHO clinical case definition was low. Low relapse rate confirms the efficacy of antibiotics. However, the need for and the best time for surgery for large Buruli ulcers requires clarification. We recommend confirmation by ZN stain at the rural health centers, since surgical intervention without delay may be necessary on the ZN positive cases to avoid progression of the disease. PCR negative patients were most likely not BU cases. Correct diagnosis and specific management of these non-BU ulcers cases are urgently needed.

Effects of olive oil and its minor phenolic constituents on obesity-induced cardiac metabolic changes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A2 Noradrenergic Lesions Prevent Renal Sympathoinhibition Induced by Hypernatremia in Rats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Rat nephrotoxic nephritis. The relation between the type and intensity of induced histological lesions and the content of antiglomerular basement membrane antibodies of the inoculated serum

Six groups of 6 rats received equal doses (0.8 ml/100 g of body weight) of different rabbit anti rat kidney sera. The titer of anti GBM antibodies in the sera was evaluated by indirect immunofluorescent test in isolated GBM (IIT GBM). Rats of groups 1, 2, 3, 5, 6 received anti rat GBM sera with titers of 1/320, 1/240, 1/160, 1/60, 1/30 respectively. Group 4 received anti rat kidney serum with a titer of 1/80. The rats of group 1 died from 1 to 5 minutes after inoculation and their kidney were congested, with hialine trombi occluding arterioles and glomerular capillaries. The rats of group 2 and one of group 3 died from 2 to 15 days after inoculation and diffuse cortical necrosis was found. The remaining rats were sacrificed 2 months after inoculation. The kidneys were normal in control group; chronic membranoproliferative glomerulonephritis was observed in group 3 and 4, membranoproliferative glomerulonephritis in group 5 and minimal changes in group 6. By immunofluorescence rabbit gammaglobulin was seen in GBM of group 3, 4, 5 and 6. The IIT GBM performed in the eluates of the kidneys revealed the presence of heterologous antibody in groups 1, 2, 3, 4, 5 and 6 and autologous antibody in groups 3, 4 and 5. One concludes that the IIT GBM identifies and quantifies antibodies which have the property of damaging the kidney.

Hepatic lesions in protein-deficient adult rats

Four groups of 10 young adult Wistar male rats were fed ad libitum on a protein-free diet for periods of 7, 28, 56 and 84 days. Control groups were fed on a 20% casein diet. Food intake and body weights of rats were registered. Plasma protein levels and liver weight and fat content were determined. Sections of the caudate lobe were studied histologically. Fatty changes were classified in three grades. Protein-deficient rats exhibited loss of body weight and had low levels of plasma protein concentration. Liver lost weight after 7 days of protein deficiency; there was a gradual reduction in liver weight as periods of protein deprivation were longer. After 7 days, liver fat concentration was not significantly higher than in the respective control group; it was significantly higher in all the other malnourished animals, As periods of protein deprivation were longer, fatty changes became more severe. Other hepatic lesions were found in 5 of the 10 rats submitted to the longest period of protein deficiency. One of the rats showed a diffuse cellular atrophy, 2 animals showed an extensive haemorrhagic necrosis, another showed a focal area of reticulum collapse and the last exhibited a distortion of the normal architecture of the liver due to diffuse reticulum collapse and early nodular regeneration; these 2 last rats showed early fibrosis in portal areas. The findings suggest that other deficiencies may complicate the protein deficiency when rats are given a protein-free diet over prolonged periods. Even if the protein-deficient diet has protective nutrients, it may be that, when rats eat less food, as occurs in prolonged experiments deficiency of one or all of these elements can occur, depending on their relative amount in diet.

Primary cutaneous amyloidosis: Clinical, laboratorial and histopathological study of 25 cases. Identification of gammaglobulins and C3 in the lesions by immunofluorescence

25 cases of primary cutaneous amyloidosis are studied. 16 patients had macular amyloidosis (MPA) and 9 lichen amyloidosus (LPA). γ-Globulins were increased in 50% of the patients. IgG and IgA were increased in the serum of 5 and 3 patients with MPA and 4 and 2 patients with LPA, respectively. Volume of amyloid deposits was similar in both forms. By direct immunofluorescence we demonstrated IgG in the amyloid deposits of 21 of the 25 cases and C3 in 13; IgM was present in 9 cases of MPA and in 3 cases of LPA. MPA was more frequent than LPA; histologically, it was impossible to distinguish MPA from LPA; correlation between serum levels of γ-globulins and their presence in amyloid deposits was weak; MPA and LPA seem to be distinct clinical manifestations of the same disease and itching does not cause transformation of MPA in LPA.

Effect of non-steroidal anti-inflammatory drugs (NSAID) on the histamine release induced by compound 48/80 and cardiac anaphylaxis in guinea-pig isolated heart

Histamine release from guinea pig heart treated with compound 48/80 was potentiated by the cyclooxygenase inhibitors indomethacin and piroxicam but not by aspirin or phenylbutazone. This differential effect suggests that the potentiation is not merely due to an inhibition of prostaglandin synthesis. Piroxicam potentiated the histamine release induced by cardiac anaphylaxis whereas indomethacin reduced this effect. The SRS-A antagonist FPL 55712 inhibited histamine release induced by cardiac anaphylaxis, but not that evoked by compound 48/80, and also prevented the potentiation due to indomethacin and piroxicam. In total, these data suggest that the potentiation of histamine release by piroxicam and indomethacin is probably due to a diversion of arachidonic acid metabolism from the cyclooxygenase to the lipoxygenase pathways. The resulting lipoxygenase products may then regulate histamine release, with the secretion due to antigen being more sensitive to such modulation than that evoked by compound 48/80.

Experimental pulmonary paracoccidioidomycosis in the Syrian hamster: morphology and correlation of lesions with the immune response.

A model for pulmonary paracoccidioidomycosis in the hamster is described. The disease was induced by intratracheal inoculation of 1.7 x 10(5) viable yeast forms of P. brasiliensis. Lung histopathology, dissemination lesions and humoral and cellular immune responses were investigated at intervals up to 24 weeks after infection. Humoral immunity was studied by immunodiffusion and complement fixation tests. Cell-mediated immunity was evaluated in vitro by the macrophage migration inhibition test in the presence of phytohaemagglutinin and P. brasiliensis soluble antigen, and in vivo by the paracoccidioidin test. Thirty out of 35 infected animals (85.7%) developed pulmonary paracoccidioidomycosis. Dissemination lesions were observed in regional lymph nodes (82.8%), liver (8.5%) and spleen (5.7%). Lung involvement was mainly around bronchi and vessels. Regional lymph nodes were severely involved from the fourth week on, acquiring a pseudotumoral aspect at later stages. Specific antibodies were detected from the fourth week on, with titres increasing progressively. The cellular immune response to phytohaemagglutinin was intact throughout the experiment and the response to P. brasiliensis antigen was already detectable by the second week and remained positive to the end of the experiment. The skin test became positive from the fourth week on. Inoculation by the intratracheal route represents a highly effective way of infecting hamsters with P. brasiliensis, with the induction of localized disease, good antibody production and intact cell immunity.