Acute and chronic effects of cortisol on milk yield, the expression of key receptors, and apoptosis of mammary epithelial cells in Saanen goats.

Cortisol (CORT) induces mammary development in late gestation and is fundamental to the differentiation of mammary epithelial cells and lactogenesis. The objective of this study was to investigate the relationship between CORT, insulin, prolactin, growth hormone, and insulin-like growth factor-1 in milk as well as the effect of CORT on the expression of receptors of insulin (INSR), prolactin (PRLR), growth hormone (GHR); we also studied the insulin-like growth factor-1 (IGF1R), glucocorticoid (NR3C1), mineralocorticoid (NR3C2), B-cell lymphoma 2 (BCL2), BCL-2-like protein X (BAX) genes, and the apoptosis rate of mammary epithelial cells of lactating Saanen goats in vivo and in vitro. The following experiments were conducted: (1) comparing hormone release in milk and blood after ACTH or a placebo administration; (2) evaluating the effect of acute CORT increases in mammary gland expression and milk yield in vivo; and (3) evaluating the effect of a chronic increase in CORT concentration in epithelial mammary cell apoptosis in vitro. In vivo, ACTH administration significantly increased CORT release but did not affect insulin, prolactin, growth hormone, and insulin-like growth factor-1 release in plasma and milk versus placebo. The results show also that a low CORT release after ACTH administration increased the expression of GHR and PRLR genes in the mammary tissue. Indeed, CORT release significantly increased the milk yield from goats subjected to ACTH versus goats subjected to the placebo. However, a higher amount of CORT added in vitro upregulated the NR3C1, GHR, PRLR, and BAX genes and downregulated the IGF1R and INSR genes, which could negatively modulate the apoptosis of mammary epithelial cells. Finally, the effect of CORT in vivo after ACTH administration demonstrated the increased expression of the PRLR and GHR genes, which may improve epithelial cell responsiveness and be associated with the positive effect of CORT observed on milk yield at mid-end lactation.

Zymosan enhances in vitro phagocyte function and the immune response of mice infected with Paracoccidioides brasiliensis.

Paracoccidioides brasiliensis is the major etiologic agent of Paracoccidioidomycosis (PCM), the most frequent human deep mycosis in Latin America. It is proposed that masking of ß-glucan in P. brasiliensis cell wall is a critical virulence factor that contributes to the development of a chronic disease characterized by a long period of treatment, which is usually toxic. In this context, the search for immunomodulatory agents for therapeutic purposes is highly desirable. One strategy is to use pattern recognition receptors (PRRs) ligands to stimulate the immune response mediated by phagocytes. Here, we sought to evaluate if Zymosan, a ß-glucan-containing ligand of the PRRs Dectin-1/TLR-2, would enhance phagocyte function and the immune response of mice challenged with P. brasiliensis. Dendritic cells (DCs) infected with P. brasiliensis and treated with Zymosan showed improved secretion of several proinflammatory cytokines and expression of maturation markers. In addition, when cocultured with splenic lymphocytes, these cells induced the production of a potential protective type 1 and 17 cytokine patterns. In macrophages, Zymosan ensued a significant fungicidal activity associated with nitric oxide production and phagolysosome acidification. Importantly, we observed a protective effect of Zymosan-primed DCs delivered intranasally in experimental pulmonary PCM. Overall, our findings support the potential use of ß-glucan-containing compounds such as Zymosan as an alternative or complementary antifungal therapy. LAY SUMMARY: We report for the first time that Paracoccidioides brasiliensis-infected phagocytes treated with Zymosan (cell wall extract from bakers' yeast) show enhanced cytokine production, maturation, and fungal killing. Also, Zymosan-primed phagocytes induce a protective immune response in infected mice.

Effect of heat stress in late gestation on subsequent lactation performance and mammary cell gene expression of Saanen goats.

Little is known about the effects of heat stress during the late gestation period on lactation in dairy goats. For this reason, 32 Saanen goats were randomly assigned to 1 of 2 groups, control (CT; n = 16) or heat stress (HS; n = 16), during late gestation. The HS goats were housed in a climatic chamber before parturition and subjected to heat stress for the last 45 d. After parturition, the HS goats were housed in the same conditions as the CT group. Mammary gland biopsies were performed on 7 goats per treatment at -30, -15, 15, and 30 d relative to parturition, so that the expression levels of several genes could be determined. The HS goats produced less milk than the CT goats did during the first half of lactation, but not during the rest of lactation. Before parturition, apoptosis-related transcripts (TP53 and BAX) were higher in the mammary glands of the HS goats than in those of the CT goats. The HS goats also had higher levels of HSPB1 gene expression during gestation and lactation. However, expression of the prolactin receptor gene was lower after parturition in the mammary glands of HS, suggesting downregulation of prolactin signaling. In summary, heat stress during final gestation reduces milk yield in the subsequent lactation. Although the upregulation of apoptosis signaling in the HS goats suggests that heat stress affects mammary cell number, the loss of the effect on milk production is more compatible with an effect on cell activity, which could be due to a downregulation of prolactin signaling.

Effect of acute stressors, adrenocorticotropic hormone administration, and cortisol release on milk yield, the expression of key genes, proliferation, and apoptosis in goat mammary epithelial cells.

Cortisol is essential to milk synthesis; however, different acute stressors and the exogenous administration of adrenocorticotropic hormone (ACTH) decrease milk yield. Therefore, the effect of cortisol on milk yield and its influence on the survival of mammary epithelial cells have not been fully elucidated. In this context, the objective of this study was to evaluate the effect of cortisol on the expression of growth hormone receptor (GHR), insulin-like growth factor type 1 (IGF1), insulin-like growth factor type 1 receptor (IGF1R), insulin-like growth factor-binding protein 3 and 5 (IGFBP3 and IGFBP5), BAX, and BCL2 genes on the proliferation and apoptotic rates of mammary epithelial cells, and on milk yield in Saanen goats. In the present study, 3 experiments were conducted: (1) comparing the in vivo effects of first milking, vaccination, vermifugation, preventive hoof trimming, and the administration of ACTH or a placebo on cortisol release in dairy goats; (2) studying the in vivo effects of immediate increases in cortisol on the mammary gland of lactating goats; and (3) studying the in vitro effects of a prolonged increase in cortisol on mammary epithelial cells obtained from lactating goats. Cortisol release by goats increased significantly after ACTH administration compared with that observed after a placebo, and the cortisol profiles after first milking, vaccination, vermifugation, hoof trimming, and ACTH administration were similar. However, there was no effect of the immediate increase in cortisol in vivo on IGF-1 release, milk yield, milk quality, or the apoptosis and proliferation rates, nor was there any effect on the expression of the target genes. Furthermore, no interaction was observed between IGF-1 and cortisol in either the in vivo or in vitro experiments. However, the addition of cortisol in vitro significantly increased the expression of the GHR and IGF1R genes, which stimulate cell proliferation, and the BAX gene, which causes apoptosis. These contrasting results can explain why cortisol did not change the rates of proliferation or apoptosis in epithelial cells. Indeed, cortisol supplementation in vitro did not change the number or apoptotic rate of epithelial cells over the course of 5 d. Finally, further studies must be performed to understand the effect of cortisol on the expression of the GHR, IGF1R, and BAX genes by epithelial cells and the roles of these genes in milk synthesis during early lactation.

Effects of different supplemental soya bean oil levels on the performance of prepubertal Saanen goats: Oestrogen and progesterone release.

The aim of this study was to investigate the effects of different levels of soya bean oil in the total diet on the growth rate, metabolic changes, and oestrogen and progesterone release in Saanen goats. After dietary adaptation, 21 prepubertal goats (weight of 29.12 ± 0.91 kg, 230 days old) were randomly distributed among three diets of D2: inclusion of 2% soya bean oil in the total diet; D3: basal diet - inclusion of 3% soya bean oil in the total diet; and D4: inclusion of 4% soya bean oil in the total diet. The basal diet (D3) was formulated to promote a daily gain of 0.140 kg. The goats were weighed, and their blood samples were collected weekly. Glucose, cholesterol, triglycerides, total protein, urea, non-esterified fatty acids, beta-hydroxybutyrate, oestrogen and progesterone in the plasma were measured. Prepubertal goats that were fed D4 exhibited a significantly lower dry matter intake, urea and cholesterol levels compared with the goats that were fed D2 and D3. Indeed, goats that were fed D4 displayed a significantly lower final weight than goats that were fed D2 and D3. In contrast, the inclusion of soya bean oil in the diet increased the progesterone and oestrogen concentrations, and goats that were fed D4 released a significantly higher concentration of progesterone than those that were fed D2 and D3. Furthermore, the percentage of goats with a progesterone level greater than 1 ng/ml (functional Corpus luteum) was significantly higher among the goats that were fed D3 and D4 than among those that were fed D2. In this study, although the inclusion of 4% soya bean oil in the diet decreased dry matter intake and growth rate, it increased progesterone concentration and the percentage of goats with a functional Corpus luteum, suggesting that the inclusion of soya bean oil accelerated puberty in prepubertal goats.

Occupational hepatitis C seroconversions in a Brazilian hospital.

BACKGROUND: There are six known cases of occupational human immunodeficiency virus (HIV) seroconversion in Brazil. However, there are neither published cases of occupational hepatitis C virus (HCV) seroconversion nor systematic studies of blood and body fluid exposures (BBFE) that could estimate the risk of HCV or HIV occupational seroconversion in Brazil. AIMS: To describe the outcomes of BBFEs in a Brazilian hospital over 12 years and 2 months. METHODS: Statistical analysis of a computerized database of exposure events recorded on printed forms. Incidence rates (IR) were calculated as the number of BBFE per 100 full-time equivalent worker-years. RESULTS: There were 1457 BBFE, 87% being percutaneous and 561 (38%) recurring in health care workers (HCWs) who reported having previous exposures. The highest IRs occurred in laboratory technicians (9.7), medical students (9.5), cleaning staff (9.5) and nursing aids (9.2). The IR in temporary employees was 13.0. Two HCWs, a nursing aid and a surgeon, seroconverted to hepatitis C after HCV exposures involving 13 G catheter needles. The risk of acquiring a HCV infection was 2 in 38 percutaneous HCV exposures, i.e. 5% (95% CI: 0.89-16.3). There were no seroconversions to HIV despite 80 percutaneous HIV exposures. CONCLUSIONS: HCV has a higher potential for occupational transmission than HIV. Measures to reduce the risks of BBFE and occupational transmission of blood-borne viral infections should be improved in Brazil.

IGFR-I expression and structural analysis of the hard palatine mucosa in an ethanol-drinking rat strain (UChA and UChB).

The study analyzed the effects of chronic alcohol ingestion on the ultrastructure of the lining epithelium of the hard palatine mucosa of rats UChA and UChB (lines with voluntary alcohol consumption) in order to contribute to the understanding of the consequences of alcohol abuse for the morphology of the digestive system. Thirty female adult animals aged 120 days were divided into three experimental groups. (1) Ten UChA rats (genetically low ethanol consumer) with voluntary intake of 10% v/v (5.45 g/kg/day) ethanol solution and water. (2) Ten UChB (genetically high ethanol consumer) rats with voluntary intake of 10% v/v (7.16 g/kg/day) ethanol solution and water. (3) Ten Wistar rats with voluntary ad libitum water intake (control group). Both groups received Nuvital pellets ad libitum. The IGFR-I expression was intense in both experimental groups. The epithelial cells of the alcoholic rats UChA and UChB showed many alterations such as the presence of lipid droplets, altered nuclei, nuclei in corneum layer and disrupted mitochondria. It was concluded that ethanol intake induces ultrastructural lesions in the hard palatine mucosa.

Morphological alterations on the prostate of Calomys callosus submitted to chronic ethanol ingestion.

The objective of the present study was to assess the possible toxic effects of chronic alcohol ingestion on the ultrastructure of the glandular epithelium of the prostate of the rodent Calomys callosus, in order to contribute to the understanding of the consequences of alcohol abuse for the morphology of the male reproductive apparatus. Sixteen adult animals aged three months were divided into two experimental groups. The control group received a solid diet and tap water, and the alcoholic group received the same solid diet and ethanol P.A. diluted 20% in water (v/v). After 120 days of treatment, all animals were anesthetized, weighed and sacrificed. At the end of treatment, mean body weight did not differ between control and alcoholic animals. The prostate epithelial cells of the alcoholic group showed intense atrophy and ultrastructural alterations such as the presence of lipid droplets, altered nuclei, ruptured mitochondrial cristae, and intense dilatation of the cisterns of the granular endoplasmic reticulum. It was concluded that 20% ethanol provokes marked lesions on the epithelium of the prostate probably interfering on the glandular secretion.

Ultrastructural changes on the hard palatine mucosa of Calomys callosus after 120 days of experimental chronic alcoholism.

The present study analyzed the toxic effects of chronic alcohol ingestion on the ultrastructure of the lining epithelium of the hard palatine mucosa of the rodent Calomys callosus, in order to contribute to the understanding of the consequences of alcohol abuse for the morphology of the digestive system. Twenty-six adult animals aged three months were divided into two experimental groups. The control group received a solid diet and tap water, and the alcoholic group received the same solid diet and ethanol P.A. diluted 20% in water (v/v). After 120 days of treatment, all animals were anaesthetised, weighed and sacrificed. At the end of treatment, mean body weight did not differ between control and alcoholic animals. The epithelial cells of the alcoholic group showed many alterations such as the presence of lipid droplets, nuclei in corneum layer, nuclei with increase peripheral chromatin and greater electron density, altered mitochondria, and intense dilatation of the intercellular spaces. It was concluded that 20% ethanol provokes marked ultrastructural lesions in the hard palatine mucosa.

A prospective comparison of Doppler echocardiography and postoperative angiography in the assessment of left internal thoracic artery graft in 72 patients submitted to minimally invasive direct coronary artery bypass.

BACKGROUND: Concerns have been raised regarding the accuracy of the left internal thoracic artery (LITA) anastomosis performed during minimally invasive direct coronary artery bypass (MIDCAB). In a prospective study, we tested the hypothesis that transthoracic Doppler echocardiography is an adequate technique to determine LITA patency when compared to "gold standard" postoperative angiography. METHODS: Seventy-two consecutive patients with single left anterior descending (LAD) coronary artery stenosis were submitted to MIDCAB performed on a beating heart using the LITA. All patients underwent transthoracic Doppler Echocardiography and angiography before discharge. LITA was considered patent when diastolic fraction (DF) of time-velocity integral was equal or greater than 0.5. FitzGibbon grading system was used to evaluate LITA patency by angiography (A=excellent; B=stenosis reducing caliber of anastomosis or trunk to < 50% of grafted coronary artery; O=occlusion). RESULTS: Angiography showed that LITA was patent in 70 (97.2%) patients, 69 of them been graded A. Adequate image and flow signal of the LITA was achieved in 65 (90.3%) patients, been considered patent in 61 (93.8%) of them. Comparison between echocardiography and angiography in these 65 patients showed a specificity of 96.8% and a sensitivity of 50%. In 7 (9.7%) patients in whom no adequate echocardiography signal was obtained, the LITA graft was normal in six and occluded in one. CONCLUSIONS: For patients whose LITA graft can be imaged, transthoracic Doppler echocardiography is highly specific and is a valuable method for noninvasive evaluation of LITA graft patency after MIDCAB.

Influence of ischemic preconditioning in myocardial protection in patients undergoing myocardial revascularization with intermittent crossclamping of the aorta. Analysis of ions and blood gases.

OBJECTIVE: To test the hypothesis that short periods of ischemia may increase the myocardial protection obtained with intermittent crossclamping of the aorta. METHODS: In the control group (18 patients), surgery was performed with systemic hypothermia at 32 degrees C and intermittent crossclamping of the aorta. Extracorporeal circulation was used. In the preconditioning group (17 patients), 2 crossclampings of the aorta lasting 3min each were added prior to the intermittent crossclamping of the conventional technique with an interval of 2min of reperfusion between them. Blood samples for analyses of pH, pCO2, pO2, sodium, potassium, calcium, and magnesium were obtained from the coronary sinus at the beginning of extracorporeal circulation (time 1), at the end of the first anastomosis (time 2), and at the end of extracorporeal circulation (time 3). RESULTS: No difference was observed in the results of the 2 groups, except for a variation in the ionic values in the different times of blood withdrawal; sodium values, however, remained stable. All patients had a good clinical outcome. CONCLUSION: The results of intermittent crossclamping of the aorta with moderate hypothermia were not altered by the use of ischemic preconditioning.

Complete myocardial revascularization using arterial grafts.

BACKGROUND: Complete arterial revascularization is important in younger patients to reduce the likelihood of future reoperation. We assessed the short-term outcome of a strategy to provide complete arterial revascularization in a cohort of young patients. METHODS: Three hundred and eighty-five patients underwent myocardial revascularization using artery grafts alone and were followed up for 30 months. One hundred fourteen patients (29.6%) had single-vessel disease, 118 (30.6%) had two-vessel disease, and 153 (39.7%) had three or more obstructed coronary arteries. Eight of the patients had undergone previous surgical revascularization. The left internal thoracic artery (LITA) was routinely used for the left anterior descending branch (LAD). In 103 patients (28.1%), the in situ right internal thoracic artery (RITA) was used for revascularization of the right coronary artery (RCA) and its branches. The RITA was sometimes used as a free graft from the aorta or as an artificial "Y" from the LITA to the diagonal and marginal branches. Other arterial conduits included the radial artery (RA) in 215 patients (55.8%), the right gastroepiploic artery (RGEA) in 24 patients (6.3%), and the inferior epigastric artery (IEA) in four patients (1.1%). RESULTS: In patients having lesions in three or more arteries, the mean number of distal anastomoses was 3.2 per patient. There were no intraoperative deaths. Hospital mortality was 1.8% (n = 7). Of the fatal cases, two were redos and two underwent combined procedures (one for left ventricular aneurysm and one for double valve replacement), while only three of the fatal cases underwent revascularization as a primary and isolated procedure. CONCLUSIONS: Complete arterial reconstruction carries an acceptably low operative mortality and excellent short-term follow-up. This strategy is particularly important for young patients to reduce the probability of future reoperation.

Tricuspid dura mater bioprostheses: more than 20-year follow-up of 3 patients.

Replacement of the tricuspid valve is sometimes necessary. We report 3 consecutive patients with tricuspid insufficiency who underwent valve replacement with glycerol-preserved, homologous dura mater cardiac bioprostheses between 1971 and 1973. The first 2 patients are well 28 and 27 years later; the last patient was lost to follow-up after 20 years. We conclude that preservation of homologous dura mater bioprostheses in glycerol may reduce rates of thromboembolism, thrombosis, and structural dysfunction during the late postoperative period.

Two family members with a syndrome of headache and rash caused by human parvovirus B19.

Human parvovirus B19 infection can cause erythema infectiosum (EI) and several other clinical presentations. Central nervous system (CNS) involvement is rare, and only a few reports of encephalitis and aseptic meningitis have been published. Here, we describe 2 cases of B19 infection in a family presenting different clinical features. A 30 year old female with a 7-day history of headache, malaise, myalgias, joint pains, and rash was seen. Physical examination revealed a maculopapular rash on the patient's body, and arthritis of the hands. She completely recovered in 1 week. Two days before, her 6 year old son had been admitted to a clinic with a 1-day history of fever, headache, abdominal pain and vomiting. On admission, he was alert, and physical examination revealed neck stiffness, Kerning and Brudzinski signs, and a petechial rash on his trunk and extremities. Cerebrospinal fluid analysis was normal. He completely recovered in 5 days. Acute and convalescent sera of both patients were positive for specific IgM antibody to B19. Human parvovirus B19 should be considered in the differential diagnosis of aseptic meningitis, particularly during outbreaks of erythema infectiosum. The disease may mimic meningococcemia and bacterial meningitis.

Myocardial revascularization with coronary endarterectomy. Stratification of risk factors for early mortality.

OBJECTIVE: To determine the risk factors for mortality related to myocardial revascularization when performed in association with coronary endarterectomy. METHODS: We assessed retrospectively 353 patients who underwent 373 coronary endarterectomies between January '89 and November '98, representing 3.73% of the myocardial revascularizations in this period of time. The arteries involved were as follows: right coronary artery in 218 patients (58.45%); left anterior descending in 102 patients (27.35%); circumflex artery in 39 patients (10.46%); and diagonal artery in 14 patients (3.74%). We used 320 (85.79%) venous grafts and 53 (14.21%) arterial grafts. RESULTS: In-hospital mortality among our patients was 9.3% as compared with 5.7% in patients with myocardial revascularizations without endarterectomy (p=0.003). Cause of death was related to acute myocardial infarction in 18 (54.55%) patients. The most significant risk factors for mortality identified were as follows: diabetes mellitus (p=0.001; odds ratio =7.168), left main disease (<0.001; 9.283), female sex (0.01; 3.111), acute myocardial infarction (0.02; 3.546), ejection fraction <35% (<0.001; 5.89), and previous myocardial revascularization (<0.001; 4.295). CONCLUSION: Coronary endarterectomy is related to higher mortality, and the risk factors involved are important elements of a poor outcome.

Diagnosis of rubella infection by detecting specific immunoglobulin M antibodies in saliva samples: a clinic-based study in Niterói, RJ, Brazil.

This study was designed to investigate whether saliva could be a feasible alternative to serum for the diagnosis of recent rubella infection in a clinic setting. Forty-five paired blood and saliva samples collected 1 to 29 days after onset of illness were tested for specific immunoglobulin (Ig) M by antibody-capture radioimmunoassay (MACRIA). Rubella IgM was detected in all serum samples and in 38 (84.4%) saliva specimens. Forty-six serum and saliva samples from other patients with rash diseases were tested by MACRIA for control purposes and two saliva specimens were reactive. The saliva test had specificity of 96%. These results indicate that salivary IgM detection may be a convenient non-invasive alternative to serum for investigation of recent rubella cases, especially for disease surveillance and control programmes.

Transmyocardial laser revascularization. Early clinical experience.

OBJECTIVE: To analyze the initial clinical experience of transmyocardial laser revascularization (TMLR) in patients with severe diffuse coronary artery disease. METHODS: Between February, 1998 and February, 1999, 20 patients were submitted to TMLR at the Heart Institute (InCor), University of São Paulo Medical School, Brazil, isolated or in association with conventional coronary artery bypass graft (CABG). All patients had severe diffuse coronary artery disease, with angina functional class III/IV (Canadian Cardiovascular Society score) unresponsive to medical therapy. Fourteen patients were submitted to TMLR as the sole therapy, whereas 6 underwent concomitant CABG. Fifty per cent of the patients had either been previously submitted to a CABG or to a percutaneous transluminal coronary angioplasty (PTCA). Mean age was 60 years, ranging from 45 to 74 years. RESULTS: All patients had three-vessel disease, with normal or mildly impaired left ventricular global function. Follow-up ranged from 1 to 13 months (mean 6.6 months), with no postoperative short or long term mortality. There was significant symptom improvement after the procedure, with 85% of the patients free of angina, and the remaining 15% of the patients showing improvement in functional class, as well as in exercise tolerance. CONCLUSION: This novel technique can be considered a low risk alternative for a highly selected group of patients not suitable for conventional revascularization procedures.

[The joint manifestations of exanthematous viroses]. / Manifestações articulares nas viroses exantemáticas.

The frequency of arthropathy was evaluated in 251 patients with clinical and serological diagnosis (specific IgM detection by enzyme immunoassay) of exanthematous disease. Arthropathy (arthralgia and/or arthritis) was more frequent in dengue fever (49%) and rubella (38.2%) cases than in human parvovirus (30%) and measles (28.1%) cases. Except for measles cases, joint complaints prevailed in adults (> or = 15 years of age) and this difference was significant. The higher frequency of arthropathy in adults was more evident in human parvovirus (75%), rubella (65%) and dengue fever (57.7%) cases than in measles cases (31%). Arthropathy was also more frequent in females for all rash diseases studied. The results of this study showed the high occurrence of joint complaints in the disease described here and the importance of laboratory confirmation for their differential diagnosis.