Morphological features and vascularization study of caprine cyclic corpus luteum

Corpus luteum is a temporary endocrine gland that regulates either the estrous cycle and pregnancy. It presents extreme dependency on the adequate blood supply. This work aims to evaluate goat corpus luteum (CL) vascular density (VD) over the estrous cycle. For that purpose, 20 females were submitted to estrus synchronization/ovulation treatment using a medroxyprogesterone intra-vaginal sponge as well as intramuscular (IM) application of cloprostenol and equine chorionic gonadotrophine (eCG). After sponge removal, estrus was identified at about 72hs. Once treatment was over, female goats were then subdivided into 4 groups (n=5 each) and slaughtered on days 2, 12, 16 and 22 after ovulation (p.o). Ovaries were collected, withdrawn and weighted. CL and ovaries had size and area recorded. Blood samples were collected and the plasma progesterone (P4) was measured through RIA commercial kits. The VD was 24.42±6.66, 36.26±5.61, 8.59±2.2 and 3.97±1.12 vessels/mm² for days 2, 12, 16 and 22 p.o, respectively. Progesterone plasma concentrations were 0.49±0.08, 2.63±0.66, 0.61±0.14 and 0.22±0.04ng/ml for days 2, 12, 16 e 22 p.o, respectively. Studied parameters were affected by the estrous cycle phase. Values greater than 12 p.o were observed. In the present work we observed that ovulation occurred predominantly in the right ovary (70% of the animals), which in turn presented bigger measures than the contra lateral one. There is a meaningful relationship between the weight and size of the ovary and these of CL (r=0.87, r=0.70, respectively, p<0.05). It is possible to conclude that morphology of goat's ovaries and plasma progesterone concentration changed according to estrous cycle stages. We propose these parameters can be used as indicators of CL functional activity.

Histopathological, immunohistochemical, and molecular study of BHV-5 infection in the central nervous system of experimentally infected calves

Bovine meningoencephalitis caused by BHV-5, a double-stranded DNA enveloped virus that belongs to the family Herpesviridae and subfamily Alphaherpesvirinae, is an important differential diagnosis of central nervous diseases. The aim of this study was to describe the histological changes in the central nervous system of calves experimentally infected with BHV-5 and compare these changes with the PCR and IHC results. Formalin-fixed paraffin-embedded central nervous system samples from calves previously inoculated with BHV-5 were microscopically evaluated and tested using IHC and PCR. All the animals presented with nonsuppurative meningoencephalitis. From 18 evaluated areas of each calf, 32.41% and 35.19% were positive by IHC and PCR, respectively. The telencephalon presented more accentuated lesions and positive areas in the PCR than other encephalic areas and was the best sampling area for diagnostic purposes. Positive areas in the IHC and PCR were more injured than IHC and PCR negative areas. The animal with neurological signs showed more PCR- and IHC-positive areas than the other animals.

Flows of Bingham Materials Through Ideal Porous Media: an Experimental and Theoretical Study

The flow of Bingham liquids through porous media has been studied. Experiments have been performed to determine the flow rate / pressure drop relationship for the flow of a grease of Binghamian rheological behavior through an array of rods of circular cross section. The yield stress and plastic viscosity of the grease have been determined with the aid of a controlled stress rotational rheometer. To investigate a wider range of the flow parameters, the mass and momentum conservation equations have been solved numerically, in conjunction with the generalized Newtonian constitutive law and the bi-viscosity model. The finite volume method has been employed to obtain the numerical solution. These numerical results also yielded a flow rate / pressure drop relationship, which is in very good agreement with the experimental results. A capillaric theory has been developed to determine an analytical relationship between the flow rate and pressure drop for flows of Bingham liquids through porous media. It is shown that the predictions of this theory are in good agreement with the experimental and numerical results.

Dialysis, time and death: comparisons of two consecutive decades among patients treated at the same Brazilian dialysis center

The survival of hemodialysis patients is likely to be influenced not only by well-known risk factors like age and comorbidity, but also by changes in dialysis technology and practices accumulated along time. We compared the survival curves, dialysis routines and some risk factors of two groups of patients admitted to a Brazilian maintenance hemodialysis program during two consecutive decades: March 1977 to December 1986 (group 1, N = 162) and January 1987 to June 1997 (group 2, N = 237). The median treatment time was 22 months (range 1-198). Survival curves were constructed using the Kaplan-Meier method and compared using the log-rank method. The Cox proportional hazard regression model was used to investigate the more important variables associated with outcome. The most important changes in dialysis routine and in patient care during the total period of observation were the progressive increase in the dose of dialysis delivered, the prohibition of potassium-free dialysate, the use of bicarbonate as a buffer and the upgrading of the dialysis equipment. There were no significant differences between the survival curves of the two groups. Survival rates at 1, 5 and 10 years were 84, 53 and 29%, respectively, for group 1 and 77, 42 and 21% for group 2. Patients in group 1 were younger (45.5 ± 15.2 vs 55.2 ± 15.9 years, P<0.001) and had a lower prevalence of diabetes (11.1 vs 27.4%, P<0.001) and of cardiovascular disease (9.3 vs 20.7%, P<0.001). According to the Cox multivariate model, only age (hazard ratio (HR) 1.04, confidence interval (CI) 1.03-1.05, P<0.001) and diabetes (HR 2.55, CI 1.82-3.58, P<0.001) were independent predictors of mortality for the whole group. Patients of group 2 had a lower prevalence of sudden death (19.1 vs 9.7%, P<0.001). After adjusting for age, diabetes and other mortality risk factors, the risk of death was 17% lower in group 2, although this difference was not statistically significant. We conclude that the negative effects of advanced age and of higher frequency of comorbidity on the survival of group 2 patients were probably offset by improvements in patient care and in the quality and dose of dialysis delivered, so that the survival curves did not undergo significant changes along time.

Pharmacological and histopathological study of cyclophosphamide-induced hemorrhagic cystitis - comparison of the effects of dexamethasone and Mesna

Chemotherapy with oxazaphosphorines, such as cyclophosphamide (CYP), is often limited by unacceptable urotoxicity. Without uroprotection, hemorrhagic cystitis (HC) becomes dose-limiting. To compare the uroprotective efficacy of classical 2-mercaptoethanesulfonic acid (Mesna) treatment with dexamethasone in CYP-induced HC, male Wistar rats (150-200 g; N = 6 in each group) were treated with saline or Mesna (40 mg/kg, ip) immediately and 4 and 8 h after ip administration of CYP (200 mg/kg). One, 2 or 3 doses of Mesna were replaced with dexamethasone (1 mg/kg, ip). The animals were sacrificed 24 h later. Cystitis was evaluated by determining the changes in bladder wet weight (BWW) and by macroscopic and microscopic analysis. CYP treatment induced a marked increased in BWW (162%, P<0.05), which was significantly inhibited by treatment with 3 doses of Mesna (P<0.05; 80%). The replacement of 1 or 2 doses of Mesna with dexamethasone reduced the increase in BWW by 83.3 and 95%, respectively. Macroscopic analysis of the bladder of rats with CYP-induced HC showed severe edema and hemorrhage, confirmed by microscopic analysis, that also showed mucosal erosion, inflammatory cell infiltration and ulcerations. The replacement of 1 or 2 doses of Mesna with dexamethasone inhibited the CYP-induced increase in BWW and almost abolished the macroscopic and microscopic alterations, with no significant difference between the effects of Mesna and dexamethasone, indicating that both drugs were efficient in blocking HC. However, although the replacement of all Mesna doses with dexamethasone reduced the edema, it did not prevent HC, suggesting that Mesna is necessary for the initial uroprotection.

Hepatitis C virus infection among Brazilian hemophiliacs: a virological, clinical and epidemiological study

We determined and analyzed risk factors of hepatitis C virus (HCV)-infected Brazilian hemophiliacs according to their virological, clinical and epidemiological characteristics. A cross-sectional and retrospective study of 469 hemophiliacs was carried out at a Brazilian blood center starting in October 1997. The prevalence of HCV infection, HCV genotypes and factors associated with HCV RNA detection was determined. The seroprevalence of anti-HCV antibodies (ELISA-3.0) was 44.6% (209/469). Virological, clinical and epidemiological assessments were completed for 162 positive patients. There were seven (4.3%) anti-HCV seroconversions between October 1992 and October 1997. During the same period, 40.8% of the positive anti-HCV hemophiliacs had abnormal alanine transaminase (ALT) levels. Plasma HCV RNA was detected by nested-RT-PCR in 116 patients (71.6%). RFLP analysis showed the following genotype distribution: HCV-1 in 98 hemophiliacs (84.5%), HCV-3 in ten (8.6%), HCV-4 in three (2.6%), HCV-2 in one (0.9%), and not typeable in four cases (3.4%). Univariate analysis indicated that older age (P = 0.017) and abnormal ALT levels (P = 0.010) were associated with HCV viremia, while the presence of inhibitor antibodies (P = 0.024) and HBsAg (P = 0.007) represented a protective factor against the presence of HCV RNA. These findings may contribute to a better understanding of the relationship between HCV infection and hemophilia.

Detection of renal dysfunction based on serum creatinine levels in a Brazilian community: the Bambuí Health and Ageing Study

There are few population-based studies of renal dysfunction and none conducted in developing countries. In the present study the prevalence and predictors of elevated serum creatinine levels (SCr > or = 1.3 mg/dl for men and 1.1 mg/dl for women) were determined among Brazilian adults (18-59 years) and older adults (>60 years). Participants included all older adults (N = 1742) and a probabilistic sample of adults (N = 818) from Bambuí town, MG, Southeast Brazil. Predictors were investigated using multiple logistic regression. Mean SCr levels were 0.77 ± 0.15 mg/dl for adults, 1.02 ± 0.39 mg/dl for older men, and 0.81 ± 0.17 mg/dl for older women. Because there were only 4 cases (0.48%) with elevated SCr levels among adults, the analysis of elevated SCr levels was restricted to older adults. The overall prevalence of elevated SCr levels among the elderly was 5.09% (76/1494). The prevalence of hypercreatinemia increased significantly with age (chi² = 26.17, P = 0.000), being higher for older men (8.19%) than for older women (5.29%, chi² = 5.00, P = 0.02). Elevated SCr levels were associated with age 70-79 years (odds ratio [OR] = 2.25, 95% confidence interval [CI]: 1.15-4.42), hypertension (OR = 3.04, 95% CI: 1.34-6.92), use of antihypertensive drugs (OR = 2.46, 95% CI: 1.26-4.82), chest pain (OR = 3.37, 95% CI: 1.31-8.74), and claudication (OR = 3.43, 95% CI: 1.30-9.09) among men, and with age >80 years (OR = 4.88, 95% CI: 2.24-10.65), use of antihypertensive drugs (OR = 4.06, 95% CI: 1.67-9.86), physical inactivity (OR = 2.11, 95% CI: 1.11-4.02) and myocardial infarction (OR = 3.89, 95% CI: 1.58-9.62) among women. The prevalence of renal dysfunction observed was much lower than that reported in other population-based studies, but predictors were similar. New investigations are needed to confirm the variability in prevalence and associated factors of renal dysfunction among populations.

Experimental chronic entrapment of the sciatic nerve in adult hamsters: an ultrastructural and morphometric study

Entrapment neuropathy is a group of clinical disorders involving compression of a peripheral nerve and interference with nerve function mostly through traction injury. We have investigated the chronic compression of peripheral nerves as an experimental procedure for detecting changes in ultrastructural nerve morphology. Adult hamsters (Mesocricetus auratus, N = 30) were anesthetized with a 25% pentobarbital solution and received a cuff around the right sciatic nerve. Left sciatic nerves were not operated (control group). Animals survived for varying times (up to 15 weeks), after which they were sacrificed and both sciatic nerves were immediately fixed with a paraformaldehyde solution. Experimental nerves were divided into segments based upon their distance from the site of compression (proximal, entrapment and distal). Semithin and ultrathin sections were obtained and examined by light and electron microscopy. Ultrastructural changes were qualitatively described and data from semithin sections were morphometrically analyzed both in control and in compressed nerves. We observed endoneurial edema along with both perineurial and endoneurial thickening and also the existence of whorled cell-sparse structures (Renaut bodies) in the subperineurial space of compressed sciatic nerves. Morphometric analyses of myelinated axons at the compression sites displayed a remarkable increase in the number of small axons (up to 60%) in comparison with the control axonal number. The distal segment of compressed nerves presented a distinct decrease in axon number (up to 40%) comparatively to the control group. The present experimental model of nerve entrapment in adult hamsters was shown to promote consistent histopathologic alterations analogous to those found in chronic compressive neuropathies.

Apolipoprotein E polymorphism distribution in an elderly Brazilian population: the Bambuí Health and Aging Study

Apolipoprotein E (ApoE) is one of the most extensively studied genes in the context of aging, but there are few population-based studies on ApoE polymorphism in the elderly in developing countries. The objective of the present study was to assess ApoE allele and genotype distribution in a large elderly community-based sample and its association with age, sex and skin color. Participants included 1408 subjects (80.8% of all residents aged ³60 years) residing in Bambuí city, MG, Brazil. The DNA samples were subjected to the polymerase chain reaction amplification, followed by the restriction fragment length polymorphism technique, with digestion by HhaI. Analysis was carried out taking into consideration the six ApoE genotypes (e3/e3, e3/e4, e2/e3, e4/e4, e2/e4, and e2/e2), the three ApoE alleles, and the number of ApoE4 alleles for each individual. The e3 allele predominated (80.0%), followed by e4 (13.5%) and e2 (6.5%). All six possible genotypes were observed, the e3/e3 genotype being the most frequent (63.4%). This distribution was similar to that described in other western populations. Sex was not associated with number of ApoE4 alleles. Black skin color was significantly and independently associated with the presence of two ApoE4 alleles (age-sex adjusted OR = 7.38; 95%CI = 1.93-28.25), showing that the African-Brazilian elderly have a high prevalence of the e4 allele, as observed in blacks from Africa. No association between number of ApoE4 alleles and age was found, suggesting the absence of association of ApoE genotype with mortality in this population.

A safety and feasibility study of cell therapy in dilated cardiomyopathy

The aim of this study was to determine if bone marrow mononuclear cell (BMMC) transplantation is safe for moderate to severe idiopathic dilated cardiomyopathy (IDC). Clinical trials have shown that this procedure is safe and effective for ischemic patients, but little information is available regarding non-ischemic patients. Twenty-four patients with IDC, optimized therapy, age 46 ± 11.6 years, 17 males, NYHA classes II-IV, and left ventricular ejection fraction <35% were enrolled in the study. Clinical evaluation at baseline and 6 months after stem cell therapy to assess heart function included echocardiogram, magnetic resonance imaging, cardiopulmonary test, Minnesota Quality of Life Questionnaire, and NYHA classification. After cell transplantation 1 patient showed a transient increase in enzyme levels and 2 patients presented arrhythmias that were reversed within 72 h. Four patients died during follow-up, between 6 and 12 weeks after therapy. Clinical evaluation showed improvement in most patients as reflected by statistically significant decreases in Minnesota Quality of Life Questionnaire (63 ± 17.9 baseline vs 28.8 ± 16.75 at 6 months) and in class III-IV NYHA patients (18/24 baseline vs 2/20 at 6 months). Cardiopulmonary exercise tests demonstrated increased peak oxygen consumption (12.2 ± 2.4 at baseline vs 15.8 ± 7.1 mL·kg-1·min-1 at 6 months) and walked distance (377.2 ± 85.4 vs 444.1 ± 77.9 m at 6 months) in the 6-min walk test, which was not accompanied by increased left ventricular ejection fraction. Our findings indicate that BMMC therapy in IDC patients with severe ventricular dysfunction is feasible and that larger, randomized and placebo-controlled trials are warranted.

Histochemistry and morphoanatomy study on guava fruit during ripening

Guava (Psidium guajava L.) is a highly perishable fruit due to its intense metabolism during ripening. Information on the enzyme activities that degrade pectic substances, as well as the amount of pectin, is very contradictory and not clearly defined. Thus, this study aimed to monitor the changes occurred in the fruit during ripening through histochemical, physical, and scanning microscopy processes. Guavas were picked at the half-mature stage and stored for 9 days at 22 ± 1 °C and 78 ± 1% RH. The analyses conducted on the day of harvest (0) and each day of storage (1, 2, 3, 4, 5, 6, 7, and 8 days) were: firmness and histochemical analyses (ferric chloride, lugol, comassie blue, vanillin hydrochloric, and ruthenium red) observed under an optic microscope and a scanning electron microscope. Ruthenium red showed a high amount of pectin in the cell wall on day zero as well as its decrease in the wall during ripening and its accumulation in the central area of the cell. Scanning microscopy showed loss of the cell structure during ripening. Those observations suggest that the pectin is the main polymer responsible for firmness maintenance in the guava fruit.

Influence of different sanitizers on food contaminant bacteria: effect of exposure temperature, contact time, and product concentration

The efficiency of four Sanitizers - peracetic acid, chlorhexidine, quaternary ammonium, and organic acids - was tested in this work using different bacteria recognized as a problem to meat industry, Salmonella sp., S. aureus, E. coli and L. monocytogenes. The effects of sanitizer concentration (0.2, 0.5, 0.6, 1.0, 1.1 and 1.4%), at different temperatures (10 and 45 °C) and contact time (2, 10, 15, 18 and 25 minutes) were evaluated. Tests in an industrial plant were also carried out considering previously obtained results. In a general way, peracetic acid presented higher efficiencies using low concentration (0.2%) and contact time (2 minutes) at 10 °C. The tests performed in industrial scale showed that peracetic acid presented a good performance in concentration and contact time lower than that suggested by the suppliers. The use of chlorhexidine and quaternary ammonium led to reasonable results at the indicated conditions, and organic acids were ineffective under concentration and contact time higher than those indicated by the suppliers in relation to Staphylococcus aureus. The results, in general, show that the choice for the most adequate sanitizer depends on the microorganism contaminant, the time available for sanitizer application, and also on the process cost.

Quality of eggs sold in different commercial establishments and the study of the conditions of storage

The objective of this study was to investigate the influence of storage conditions on the physicochemical (mass, albumen height, pH, and Haugh unit) and microbiological (Salmonella spp., determination of the Total and Thermotolerant Coliforms, and Counting of the Mesophilic Aerobic Bacteria) quality of eggs. In the first experiment, a questionnaire was applied, and 33 samples of eggs were collected for the Salmonella spp analysis. In the second experiment, the eggs were collected from supermarkets, open markets, and distributors for physicochemical analysis. In the third experiment, 175 eggs were collected from the distributor, packaged in cardboard boxes lined with plastic wrapping, stored at 5 °C and 28 °C, and the physicochemical and microbiological analyses were performed at 7, 14, and 21 days of storage. In the first experiment, 100% of the samples analyzed showed no Salmonella spp. In the second experiment, it was found that the values of physicochemical parameters were in agreement with those in the literature. However, in the third experiment, the physicochemical parameter results showed statistical difference during storage and temperatures studied. Salmonella spp. were found in the samples stored at room temperature and in the refrigerated samples. Mesophilic microorganisms with values ranging from <10 CFU g- 1 (estimated) to 8.0 × 10³ CFU g- 1 and coliforms to 4 NMP.g- 1 were also found, but the presence of E. coli was not confirmed.

Prevention of enzymatic browning of yacon flour by the combined use of anti-browning agents and the study of its chemical composition

Yacon roots present functional properties because of the high levels of fructooligosaccharides (FOS), which are considered as prebiotic fibers. In addition, yacon roots are rich in phenolic compounds. During the processing of yacon, the freshly cut surface undergoes rapid enzymatic browning. Control of enzymatic browning during processing is very important to preserve the appearance of yacon flour. In this study, it was evaluated the combined effect of anti-browning agents (ascorbic acid, citric acid and L-cysteine) on the inhibition of enzymatic browning of yacon, using Response Surface Methodology. The yacon pre-treated with anti-browning agents in concentrations of 15.0 mM for ascorbic acid, 7.5 mM for citric acid and 10.0 mM for L-cysteine was used for the processing of flour. Yacon flour presented an attractive color and good sensory properties, without residual aroma. The contents of FOS and phenolic compounds obtained in yacon flour were 28.60 g.100 g- 1 and 1.35 g.100 g- 1. Yacon flour can be considered as a potential functional food, especially due to high levels of FOS, which allows for its use in formulation of various foods.

Cajá-flavored drinks: a proposal for mixed flavor beverages and a study of the consumer profile

Mixed flavor beverages represent a trend that is gaining the allegiance of potential fruit juice consumers. The present study proposed to prepare mixed flavor beverages and verify their consumer acceptance. Cajá beverage (sample A) was used as the standard. The other beverages were prepared by mixing the cajá-flavored product with other flavors: strawberry (B), pineapple (C), jabuticaba (D), mango (E) and cashew (F). The consumer profiles in the two regions studied were similar. Overall beverages B, A and F were the most accepted, with scores of 7.7, 6.4 and 6.2, respectively. Internal Preference Mapping showed that most of the consumers were located near beverages A, B and F, confirming the acceptance results. The consumers indicated appearance and flavor as the most appreciated characteristics in beverages A, B and F. Beverages A, B and F presented higher total soluble solids contents and viscosities than the other beverages. Consumer segmentation did not depend on the different levels of familiarity with the cajá flavor. Thus the preparation of mixed flavor beverages of cajá-strawberry and cajá-cashew is an excellent proposal because it presents flavors with good potential for marketing in different regions of Brazil.