Towards the Development of a Female Animal Model of T1DM Using Hyaluronic Acid Nanocoated Cell Transplantation: Refinements and Considerations for Future Protocols

Female mice (Black 6 strain) (C57BL/6) aged 6 weeks were subject to low dose streptozotocin (STZ) treatment for five consecutive days to mimic type 1 diabetes mellitus (T1DM) with insulitis. At two weeks after STZ injections, evaluation of the elevated glucose levels was used to confirm diabetes. The diabetic mice were then subject to the transplantation of pancreatic β-cells (MIN-6 line). Four groups of mice were studied. The first group was injected with saline-only acting as the placebo surgery control, also known as SHAM group, the second and third groups were injected with MIN-6 single cells and polyethylene glycol-modified dipalmitoyl-glycerol-phosphatidyl ethanolamine (PEG-DPPE) modified MIN-6 single cells (500 µg per 1.10⁶ cells), respectively, while the fourth group was injected with hyaluronic acid (HA)-coated MIN-6 single cells (5 bilayers). At seven- and fourteen-days following transplantation, the mice were euthanised. The renal and pancreatic tissues were then collected and histologically analysed. The induction of diabetes in female mice, through five-consecutive daily STZ injections resulted in inconsistent glycaemic levels. Interestingly, this shows an incomplete diabetes induction in female mice, of which we attribute to sex dimorphism and hormonal interferences. Transplantation failure of free-floating encapsulated cells was unable to decrease blood glucose hyperglycaemia to physiological ranges. The result is attributed to deprived cell–cell interactions, leading to decreased β-cells functionality. Overall, we highlight the necessity of refining T1DM disease models in female subjects when using multiple low-dose STZ injections together with transplantation protocols. Considerations need to be made regarding the different developmental stages of female mice and oestrogen load interfering with pancreatic β-cells susceptibility to STZ. The use of pseudo islets, cell aggregates and spheroids are sought to improve transplantation outcome in comparison to free-floating single cells.

Targeting Glucose Transporters for Breast Cancer Therapy: The Effect of Natural and Synthetic Compounds

Reprogramming of cellular energy metabolism is widely accepted to be a cancer hallmark. The deviant energetic metabolism of cancer cells-known as the Warburg effect-consists in much higher rates of glucose uptake and glycolytic oxidation coupled with the production of lactic acid, even in the presence of oxygen. Consequently, cancer cells have higher glucose needs and thus display a higher sensitivity to glucose deprivation-induced death than normal cells. So, inhibitors of glucose uptake are potential therapeutic targets in cancer. Breast cancer is the most commonly diagnosed cancer and a leading cause of cancer death in women worldwide. Overexpression of facilitative glucose transporters (GLUT), mainly GLUT1, in breast cancer cells is firmly established, and the consequences of GLUT inhibition and/or knockout are under investigation. Herein we review the compounds, both of natural and synthetic origin, found to interfere with uptake of glucose by breast cancer cells, and the consequences of interference with that mechanism on breast cancer cell biology. We will also present data where the interaction with GLUT is exploited in order to increase the efficiency or selectivity of anticancer agents, in breast cancer cells.

Intake, digestibility, ingestive behavior, and nitrogen balance of goats fed with diets containing residue from tamarind fruit

This study is aimed at determining the maximum inclusion level of tamarind (Tamarindus indica) residues in the diet of goats on intake, digestibility, ingestive behavior, and nitrogen (N) balance. Twenty-four crossbred (Boer × undefined breed) castrated goat kids (5 months old and with an initial weight of 23.9 ± 0.3 kg) were assigned in a completely randomized design (4 treatments and 6 replicates). Diets consisted of Tifton 85 (Cynodon sp.) hay as the roughage (400 g/kg) source and concentrate (600 g/kg); the levels of tamarind residue inclusion were 0.0, 7.0, 14.0, and 21.0% on a dry matter (DM) basis. The experimental period lasted 23 days (15 of adaptation and 8 of sampling). Inclusion of tamarind residue in the goat kid diets did not affect (P > 0.05) the intake and digestibility of DM, crude protein, neutral detergent fiber (NDF), and total digestible nutrient; intake of N, urinary N, and retained N (g/day); time spent ruminating; numbers of times/day feeding, ruminating, or idling; eating efficiency of DM and NDF; number of boluses/day; and amount (g) of DM/bolus. However, there were a linear reduction in ether extract digestibility (P = 0.011) and a linear decreasing trend in non-fibrous carbohydrate digestibility (P = 0.083). The addition of tamarind residue had a positive linear effect (P = 0.041) on the time spent feeding and promoted a decreasing linear trend for the time spent idling (P = 0.063). It is recommended to include the residue from tamarind fruit at a level of 21% in diets for goat kids, as it does not affect nutrient intake and digestibility and the N balance.

Effect of replacing ground corn and soybean meal with licuri cake on the performance, digestibility, nitrogen metabolism and ingestive behavior in lactating dairy cows

Licuri (Syagrus coronate) cake is a biodiesel by-product used in ruminant feed as a beneficial energy source for supplementation in managed pastures. The objective was to evaluate the performance, digestibility, nitrogen balance, blood metabolites, ingestive behavior and diet profitability of eight crossbred Holstein (3/4)×Gyr (5/8) multiparous cows (480±25 kg BW and 100 days milking) grazing and supplemented with licuri cake partially replacing ground corn and soybean meal in concentrate (0, 200, 400 and 600 g/kg in dry matter (DM)), distributed in an experimental duplicated 4×4 Latin square design. Licuri cake partially replacing ground corn and soybean meal increased (P<0.01) the intake and digestibility of ether extract and decreased the non-fiber carbohydrates; however, there were no influences on the intakes of DM, CP, NDF and total digestible nutrients (TDN). The digestibilities of DM, CP and NDF were not influenced by licuri cake addition. There was a decrease trend on TDN digestibility (P=0.08). Licuri cake replacing ground corn and soybean meal in concentrate did not affect the intake; fecal, urinary and mammary excretions; N balance; and triglycerides concentrations. However, the blood urea nitrogen (P=0.04) concentration decreased with the licuri cakes inclusion in cow supplementation. There was an increasing trend for serum creatinine (P=0.07). Licuri cake inclusion did not affect body condition score, production, yield, protein, lactose, total solids and solid non-fat contents of milk and Minas frescal cheese. There was a linear decrease in average daily weight gain (g/day). The milk fat concentration and cheese fat production (P<0.1) presented a linear increase with partial replacement of ground corn and soybean meal with licuri cakes. The addition of licuri cake did not alter the time spent feeding, ruminating or idling. There was an increasing trend in NDF feeding efficiency (P=0.09). The replacing of ground corn and soybean meal with licuri cake up to 600 g/kg decreased the concentrate cost by US$0.45/cow per day. Licuri cake replacing corn and soybeans (400 g/kg) in concentrate promoted a profit of US$0.07/animal per day. Licuri cake is indicated to concentrate the supplementation of dairy cows with average productions of 10 kg/day at levels up to 400 g/kg in the concentrate supplement because it provides an additional profit of US$0.07/animal per day and increased milk and Minas frescal cheese fat without negative effects on productive parameters.

Atherosclerosis: analysis of the eNOS (T786C) gene polymorphism

The coronary arteriosclerotic disease is the most common cardiovascular disease. Atherosclerosis affects large- and medium-sized arteries leading to severe thrombosis or artery stenosis that could evolve to myocardial infarction, ischemic stroke, ischemic injury of kidneys and intestines, and several other life-threatening clinical manifestations. Nitric oxide has been shown to be a promising therapeutic agent against cardiovascular diseases. The eNOS gene assumes several important functions, including regulation of vascular tone and regional blood flow, the suppression of vascular smooth muscle cell proliferation, and modulation of leukocyte-endothelium interactions. The T786C polymorphism is an important point mutation, where thymine is changed to cytosine. T786C significantly reduces the activity of the eNOS promoter gene. Two hundred and ninety-seven peripheral blood samples were collected from patients with the previous diagnosis of atherosclerotic disease based on clinical examination and confirmed by imaging methods. Results were compared using the chi-square test and the G-test. In the present study, the TC genotype was more frequent in both case and control groups with no statistically significant difference. Comparing the relation TC/TT and CC genotypes in the case and control groups, there was no statistically significant difference. No significant difference was found when genotypes were analyzed regarding gender and smoking. Our results suggest a strong tendency of the T allele, in single or double dose, to be associated with atherosclerosis that was not confirmed by the scientific data.

Analysis of p53 gene polymorphism (codon 72) in symptomatic patients with atherosclerosis

Atherosclerosis is a multifactorial pathological disease that alters the morphology and function of arterial walls. The atheroma growth leads to vessel hardening and lumen narrowing, limiting the blood flow. The atheroma plaque can eventually break, expose highly thrombogenic material and lead to platelet activation and subsequent formation of a thrombus that may block blood flow in loco, or even leading to obstruction of other vessels with a smaller diameter. This process is one of the main determinants of the clinical manifestations of atherosclerosis, such as coronary artery disease, ischemic stroke, and peripheral arterial disease. Although the inflammatory theory about atherosclerosis is the most renowned one, observations point to common biological characteristics between cancer and atherosclerosis suggesting a possible association between p53 and atherosclerotic diseases. We collected peripheral blood samples from 200 individuals with clinical manifestations of atherosclerotic disease and 100 individuals without manisfestation of the disease to form the control group. DNA was subjected to molecular analysis (PCR) to identify the polymorphism of the p53 gene. We have not found any relationship between the polymorphism of the p53 gene and atherosclerosis in the population studied (P = 0.36). There was no relationship between atherosclerosis, polymorphism of p53 and the variables accounted: smoking habit (P = 0.72, 0.51 and 0.62 for smokers, non-smokers and former smokers respectively), alcohol consumption (P = 0.17 for individuals with drinking habits and 0.38 for those who do not consume alcohol beverage), systemic arterial hypertension (P = 0.60), diabetes mellitus (P = 0.34), and dyslipidemia (P = 0.89). Our population has a high rate of miscegenation and heterozygotes, and according to studies the arginine variant is more related to plaque formation because it induces apoptosis more frequently when compared to the proline variant. According to our results, there is no association between the polymorphism of the p53 gene, atherosclerosis and its risk factors in the population studied.

Molecular analysis of the GSTT1 gene polymorphism in patients with clinical manifestation of atherosclerosis

Atherosclerosis is a chronic inflammatory disease formed by the accumulation of lipids in the innermost layer and large-caliber artery (tunica intima). This accumulation, along with platelet factors, stimulates the proliferation of muscle cells in this region. Over than 400 genes may be related to the pathology since they regulate endothelial function, coagulation, inflammation, metabolism of amino acids, lipids, and carbohydrates. Glutathione S-transferases (GST) are enzymes that catalyze the polymorphic detoxification of metabolites produced by oxidative stress within the cells, which is induced by reactive oxygen species. GSTs are one of the defense mechanisms against oxidative stress damage. Due to genetic, cultural, and environmental factors, the rate of atherosclerosis is higher; however, an early diagnosis is crucial for the prevention and treatment of several complications related to the disease. The present study aimed to analyze the frequency of GSTT1 genotypes regarding the presence or absence of the polymorphism in patients with clinical manifestation of atherosclerosis. We collected 200 samples of peripheral blood of patients with the previous diagnosis of atherosclerosis based on clinical examination and imaging, and 100 samples of peripheral blood to compose the control group of patients without clinical manifestation of atherosclerosis. The polymorphism was assessed by PCR and analyzed on the agarose gel stained with 2.0% ethidium bromide. The frequency of the GSTT1 gene polymorphism was compared using the chi-square test (P < 0.05) and the G-test. In the case group, we detected 85.5% of patients with the GSTT1 genotype present and 14.5% of patients with the null genotype. A significant difference was observed between groups (case vs control) for the presence of the GSTT1 polymorphism. According to the analysis of the variable alcohol consumption, we found that in the case group the presence of the GSTT1 gene was higher in individuals who reported not drinking alcohol. In this study, the presence of the GSTT1 gene polymorphism in male patients with atherosclerosis was 1.5 times higher when compared to female patients. Regarding the variable time of smoking, we found that this genotype was more frequent in smokers for both case and control groups.

Polymorphism of the gene eNOS G894T (Glu298Asp) in symptomatic patients with aterosclerosis

Atherosclerotic and its cardiovascular complications are responsible for 17.5 million deaths a year, according to the World Health Organization. There is consensus that atherosclerosis involves multiple pathogenic processes initiated by endothelial dysfunction, with inflammation and vascular proliferation determining alterations in the matrix, with consequent formation of the atheromatous plaque and its clinical implications. Risk factors such as hypertension, diabetes mellitus, dyslipidemia, and smoking are widely known. Currently, genotyping, which is not directly related to these factors, is not accepted to estimate the risk of cardiovascular diseases, but strong evidence indicates several polymorphic genes as factors of risk and progression leading to complications of the disease. Among the genes involved, eNOS (endothelial nitric oxide synthase gene), which is responsible for the production of endothelial nitric oxide (an important arterial vasodilator), when presented in polymorphic variation can determine production, malfunction, and predisposition to atherosclerosis. In the present study, we analyzed the G894T polymorphism of the eNOS gene in groups of individuals diagnosed with atherosclerosis and in a control group. We collected 200 blood samples from patients previously diagnosed with atherosclerosis and 100 samples formed the control group. The genotyping analysis for polymorphism of the eNOS gene was determined by PCR. We considered variables such as gender, smoking, smoking history, and alcohol consumption; statistical differences were found in the distribution of case and control groups (P = 0.0378) and in non-smoking patients (P = 0.0263). In the other associations, no statistically significant difference was found. In the population studied, the frequency of the heterozygous genotype (GT) was much higher than in the other populations (GG and TT) in both groups (case and control). The GG genotype showed greater susceptibility to atherosclerosis. Association of the GG genotype in non-smokers also showed greater susceptibility. Gender, alcohol consumption, smoking, and smoking history did not influence atherosclerosis.

Oral fish oil positively influences nutritional-inflammatory risk in patients with haematological malignancies during chemotherapy with an impact on long-term survival: a randomised clinical trial

BACKGROUND

Studies suggest that the ingestion of fish oil (FO), a source of the omega-3 polyunsaturated fatty acids docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), can reduce the deleterious side-effects of chemotherapy. The aim of this randomised clinical trial was to evaluate the effect of supplementation with oral FO for 9 weeks on nutritional parameters and inflammatory nutritional risk in patients with haematological malignancies during the beginning of chemotherapy.

METHODS

Twenty-two patients with leukaemia or lymphoma were randomised to the unsupplemented group (UG) (n = 13) or supplemented group (SG) (n = 9). SG received 2 g/day of fish oil for 9 weeks. Nutritional status, serum acute-phase proteins and plasma fatty acids were evaluated before (T0) and after (T1) the intervention period. Data were analysed using two models; model 1, comprising data from all patients included in the study, and model 2, comprising data from UG patients with no increase in the proportions of EPA and DHA in plasma and data from SG patients showing an at least 100% increase in plasma EPA and DHA.

RESULTS

SG showed an increased plasma proportion of EPA and DHA in both models. In model 2, C-reactive protein (CRP) and CRP/albumin ratio showed larger reductions in the SG. Overall long-term survival in both models (465 days after the start of the chemotherapy) was higher in the group ingesting fish oil (P < 0.05).

CONCLUSIONS

These findings indicate an improved nutritional-inflammatory risk and potential effects on long-term survival in patients with haematological malignancies supplemented with FO during the beginning of chemotherapy.

GSTM1 polymorphism in patients with clinical manifestations of atherosclerosis

Atherosclerosis is characterized by lesions, called atheroma or atheromatous plaques, in the inner layer of blood vessels, which block the vascular lumen and weaken the underlying tunica media. Several modifiable and non-modifiable risk factors for the development of atherosclerosis exist. The modifiable risk factors include hypertension, smoking, obesity, high LDL and low HDL cholesterol levels, sedentary lifestyle, and stress; the non-modifiable factors include diabetes mellitus, family history of hypertension and heart disease, thrombophilia, sex, age, and genetic factors. The association of polymorphisms in GST with coronary artery disease has been studied since the polymorphisms can affect enzyme activity and contribute to the onset of atherosclerosis. We analyzed polymorphisms in GSTM1 in individuals diagnosed with atherosclerosis as well as in healthy individuals (control group). The frequency of the GSTM1 present genotype in the atherosclerosis group was 1.2 times higher than that observed in the control group. We found no sex- or alcohol-consumption-dependent differences between the occurrences of the present and null genotypes. However, the GSTM1 present genotype occurred in 52.6% individuals with atherosclerosis who reported smoking 20 or more cigarettes per day and in 60% individuals who smoked 10 to 20 cigarettes per day (P = 0.0035). In addition, the GSTM1 present genotype was more frequent in individuals who reported being former smokers - 45.5% in individuals with atherosclerosis who smoked for more than 20 years and 50% each for individuals in the control group who smoked for less than 10 years or for 10 to 20 years, respectively (P = 0.0240).

Neuromuscular activity of Bothrops fonsecai snake venom in vertebrate preparations

The neuromuscular activity of venom from Bothrops fonsecai, a lancehead endemic to southeastern Brazil, was investigated. Chick biventer cervicis (CBC) and mouse phrenic nerve-diaphragm (PND) preparations were used for myographic recordings and mouse diaphragm muscle was used for membrane resting potential (RP) and miniature end-plate potential (MEPP) recordings. Creatine kinase release and muscle damage were also assessed. In CBC, venom (40, 80 and 160μg/ml) produced concentration- and time-dependent neuromuscular blockade (50% blockade in 85±9 min and 73±8 min with 80 and 160μg/ml, respectively) and attenuated the contractures to 110μM ACh (78-100% inhibition) and 40mM KCl (45-90% inhibition). The venom-induced decrease in twitch-tension in curarized, directly-stimulated preparations was similar to that in indirectly stimulated preparations. Venom (100 and 200μg/ml) also caused blockade in PND preparations (50% blockade in 94±13 min and 49±8 min with 100 and 200μg/ml, respectively) but did not alter the RP or MEPP amplitude. In CBC, venom caused creatine kinase release and myonecrosis. The venom-induced decrease in twitch-tension and in the contractures to ACh and K(+) were abolished by preincubating venom with commercial antivenom. These findings indicate that Bothrops fonsecai venom interferes with neuromuscular transmission essentially through postsynaptic muscle damage that affects responses to ACh and KCl. These actions are effectively prevented by commercial antivenom.

GSTM1 polymorphism in patients with primary open-angle glaucoma

Primary open-angle glaucoma (POAG) is characterized by loss of retinal ganglion cells, optic nerve damage and irreversible loss of visual field. Glaucoma is the second leading cause of blindness worldwide. It was estimated that in 2010 there were about 60.5 million glaucoma cases worldwide; among these patients, 4.5 million will become bilaterally blind. Glutathione S-transferases (GST) are a group of drug-metabolizing enzymes of phase-II that act in the detoxification of xenobiotics and inactivate end-products formed as secondary metabolites during oxidative stress. Through PCR amplification, we analyzed the GSTM1 gene in DNA samples from 25 patients with POAG and 25 controls; 14 of the patients presented the GSTM1 gene null polymorphism while only eight of the control group had this gene.Although the POAG patients had a higher frequency of GSTM1, the difference was not significant (P = 0.0874); this lack of significance could be due to the small sample size.

Endogenous fraction and urinary recovery of purine derivatives obtained by different methods in Nellore cattle

Two experiments were conducted to assess the endogenous fraction of purine derivative (PD) excretion, urinary recovery, and intestinal digestibility of purines in Nellore heifers. For both experiments, 8 Nellore heifers fitted with ruminal and abomasal cannulas were allocated to two 4 × 4 Latin squares. The diets were based on corn silage and concentrate (60 and 40% DM basis, respectively); feces and urine samples were obtained by total collection, and abomasal DM flow was estimated using indigestible NDF as an internal marker. In Exp. I, 4 of the 8 heifers (BW 258 ± 20 kg) were also fitted with ileal cannula. The planned treatments were 4 different DMI: 1.2, 1.6, 2.0, and 2.4% of BW (DM basis). The endogenous losses and purine recovery as urinary PD were estimated using linear regression between daily urinary PD excretion (Y) and daily abomasal flow of purine bases (X), expressed in millimoles per kilogram of BW(0.75). In Exp. II, the same 8 Nellore heifers (BW of 296 ± 15 kg) were fed at 1.37% BW (DM basis). The treatments were the infusion of purines (RNA from torula yeast, type VI, Sigma) into the abomasum in increasing amounts (0, 33, 66, and 100 mmol/d). All statistical analyses were performed using the PROC MIXED procedure in SAS. In Exp. I, the DMI range was 1.16 to 1.84% of BW and did not affect (P > 0.05) the apparent RNA digestibility in the small intestine, which had a mean of 75.6%, and a true digestibility of 93.0%. The mean ratio of the N-RNA to the total-N in the ruminal bacteria was 0.137. The daily urinary PD excretion (Y, mmol/kg of BW(0.75)) was a function of RNA flow in the abomasum (X, mmol/kg of BW(0.75)): Y = 0.860X + 0.460, where 0.860 and 0.460 were the PD recovery of purines and the endogenous fraction (in mmol/kg of BW(0.75)), respectively. In Exp. II, the daily urinary PD excretion was a function of RNA flow in the abomasum: Y = 0.741X + 0.301, where 0.741 and 0.301 were the recovery of PD in urine of infused purines and the endogenous losses (in mmol/kg of BW(0.75)), respectively. In conclusion, our data suggest that in Nellore heifers the respective values of endogenous PD excretion (mmol/kg of BW(0.75)), urinary recovery of the purines absorbed in the abomasum, and true digestibility of RNA in the small intestine were 0.30, 0.80, and 0.93.

Influence of different levels of concentrate and ruminally undegraded protein on digestive variables in beef heifers

This experiment evaluated the effect of 2 levels of diet concentrate (20 and 40% of DM) and 2 levels of ruminally undegraded protein (RUP: 25 and 40% of CP) on nutrient intake, total and partial apparent nutrient digestibility, microbial protein synthesis, and ruminal and physiological variables. Eight Nellore heifers (233 +/- 14 kg of BW) fitted with ruminal, abomasal, and ileal cannulas were used. The animals were held in individual sheltered pens of approximately 15 m(2) and fed twice daily at 0800 and 1600 h for ad libitum intake. Heifers were allocated in two 4 x 4 Latin square designs, containing 8 heifers, 4 experimental periods, and 4 treatments in a 2 x 2 factorial arrangement. All statistical analyses were performed using PROC MIXED of SAS. Titanium dioxide (TiO(2)) and chromic oxide (Cr(2)O(3)) were used to estimate digesta fluxes and fecal excretion. Purine derivative (PD) excretion and abomasal purine bases were used to estimate the microbial N (MN) synthesis. No significant interaction (P > 0.10) between dietary levels of RUP and concentrate was observed. There was no effect of treatment (P = 0.24) on DMI. Both markers led to the same estimates of fecal, abomasal, and ileal DM fluxes, and digestibilities of DM and individual nutrients. Ruminal pH was affected by sampling time (P < 0.001), but no interaction between treatment and sampling time was observed (P = 0.71). There was an interaction between treatment and sampling time (P < 0.001) for ruminal NH(3)-N concentration. A linear decrease (P = 0.04) over sampling time was observed for the higher level of RUP, whereas a quadratic effect (P < 0.001) of sampling time was observed for the lower level of RUP. The higher level of dietary concentrate led to greater MN yield regardless of the level of RUP. The MN yield and the efficiency of microbial yield estimated from urinary PD excretion produced greater (P < 0.01) values than those estimated by either TiO(2) or Cr(2)O(3), which did not differ (P = 0.63) from each other. However, all methods yielded values that were within the range reported in the literature. In conclusion, no interactions between dietary levels of RUP and concentrate were observed for ruminal and digestive parameters. Neither RUP nor concentrate level affected DMI. Titanium dioxide showed to be similar to Cr(2)O(3) as an external marker to measure digestibility and nutrient fluxes in cattle.

Kinin B1 receptor deficiency leads to leptin hypersensitivity and resistance to obesity

OBJECTIVE

Kinins mediate pathophysiological processes related to hypertension, pain, and inflammation through the activation of two G-protein-coupled receptors, named B(1) and B(2). Although these peptides have been related to glucose homeostasis, their effects on energy balance are still unknown.

RESEARCH DESIGN AND METHODS

Using genetic and pharmacological strategies to abrogate the kinin B(1) receptor in different animal models of obesity, here we present evidence of a novel role for kinins in the regulation of satiety and adiposity.

RESULTS

Kinin B(1) receptor deficiency in mice (B(1)(-/-)) resulted in less fat content, hypoleptinemia, increased leptin sensitivity, and robust protection against high-fat diet-induced weight gain. Under high-fat diet, B(1)(-/-) also exhibited reduced food intake, improved lipid oxidation, and increased energy expenditure. Surprisingly, B(1) receptor deficiency was not able to decrease food intake and adiposity in obese mice lacking leptin (ob/ob-B(1)(-/-)). However, ob/ob-B(1)(-/-) mice were more responsive to the effects of exogenous leptin on body weight and food intake, suggesting that B(1) receptors may be dependent on leptin to display their metabolic roles. Finally, inhibition of weight gain and food intake by B(1) receptor ablation was pharmacologically confirmed by long-term administration of the kinin B(1) receptor antagonist SSR240612 to mice under high-fat diet.

CONCLUSIONS

Our data suggest that kinin B(1) receptors participate in the regulation of the energy balance via a mechanism that could involve the modulation of leptin sensitivity.

Antifungal activity of Brazilian medicinal plants involved in popular treatment of mycoses

A survey of medicinal plants used to treat common mycoses was done in the Curituba district, Sergipe State, Brazil. One hundred inhabitants were interviewed by health agents and traditional healers. Four different plants were the most cited (more than 50% of the citations): Ziziphus joazeiro, Caesalpinia pyramidalis, Bumelia sartorum and Hymenea courbaril. The aqueous extracts obtained following traditional methods and using different parts of these plants, were submitted to drop agar diffusion tests for primary antimicrobial screening. Only the water infusion extract of Ziziphus joazeiro and Caesalpinea pyramidalis presented a significant antifungal activity against Trichophyton rubrum, Candida guilliermondii, Candida albicans, Cryptococcus neoformans and Fonsecaea pedrosoi, when compared to the antifungal agent amphotericin B. The minimal inhibitory concentration (MIC) of the bioactive extracts was evaluated by the microdilution method. Best activity with a MIC of 6.5 microg/ml for both extracts was observed against Trichophyton rubrum and Candida guilliermondii. Ziziphus joazeiro and Caesalpinea pyramidalis extracts presented also low acute toxicity in murine models. The present study validates the folk use of these plant extracts and indicates that they can be effective potential candidates for the development of new strategies to treat fungal infections.

Pharmacological characterization of mouse hind paw oedema induced by Bothrops insularis (jararaca ilhoa) snake venom

Bothrops snake venoms produce marked local effects, including oedema, haemorrhage and necrosis. The ability of Bothrops insularis venom to induce oedema in mice was investigated. Venom was injected into hind paws and the change in volume over time was measured by plethysmometry. B. insularis venom (0.01-2.5 microg/paw) induced paw oedema which, at high doses (>/=0.5 microg/paw), was accompanied by haemorrhage. The peak oedematogenic response occurred 3 h after venom injection with all doses and decreased gradually thereafter, but was still elevated with high doses after 24 h. Pretreating the mice with cyproheptadine (histamine H(1) and serotonin 5-HT(2) receptor antagonist), mepyramine (histamine H(1) receptor antagonist), L-NAME (inhibitor of nitric oxide synthase), indomethacin and rofecoxib (inhibitors of cyclooxygenases), and dexamethasone (indirect inhibitor of PLA(2)) significantly attenuated venom-induced oedema, whereas methysergide, a serotonin 5-HT(1)/5-HT(2) receptor antagonist, had no effect. The administration of antivenom 30 min before or immediately after venom injection also significantly inhibited venom-induced oedema. These results show that B. insularis venom causes oedema in the mouse hind paw and that this response is mediated by histamine, nitric oxide, and arachidonic acid metabolites formed by cyclooxygenases 1 and 2. The neutralization by commercial antivenom indicates that the venom components responsible for oedema are recognized by the antivenom and share immunological identity with their counterparts in the venoms of mainland Bothrops species.

Veratryl alcohol stimulates fruiting body formation in the oyster mushroom, Pleurotus ostreatus

The oyster mushroom, Pleurotus ostreatus, cultivated in solid state on sugarcane bagasse-wheat bran (5:1) medium in the presence of veratryl alcohol resulted in an increased production of the fruiting body at earlier times compared to when the fungus was grown in the absence of veratryl alcohol. The results indicate a new physiological role for veratryl alcohol in stimulating fruiting body formation. Veratryl alcohol also stimulated laccase production during the mycelial growth stage. Evidence is also presented that laccases were involved in the physiological development of the fruiting body.

The effects of aeration and veratryl alcohol on the production of two laccases by the ascomycete Botryosphaeria sp

The ascomycete, Botryosphaeria sp, produced two extracellular constitutive laccases (PPO-I and PPO-II) active toward the substrates: 2, 2(1)-azino-bis(3-ethyl-benzthiazoline-6-sulfonic acid) [ABTS], and 2,6-dimethoxyphenol (DMP), respectively. The production of both laccases increased when the fungal isolate was grown in the presence of veratryl alcohol, and resulted in optimal laccase production (100- and 25- fold, respectively) at 40 mM. The effect of aeration on growth and laccase production was studied in baffled flasks, and showed that aeration of the cultures increased the production of both enzymes 4-5 fold in the presence of veratryl alcohol. Both laccases were susceptible to inhibition by azide, acetate and chloride anions. Veratryl alcohol inhibited the laccase-catalyzed polymerization of DMP. Growing cultures of Botryosphaeria sp. produced an exopolysaccharide of the beta-glucan type whose synthesis was depressed when grown in the presence of veratryl alcohol.

Speciation of heavy metals in estuarine sediments in the northeast of Brazil

An analytical procedure involving a three-step sequential extraction was used to determine the chemical association of heavy metals (Zn, Cr, Mn and Fe) with the major phases (exchangable, reducible and oxidizable) in samples from a fishpond of estuarine sediments. The pond is located in the Capibaribe River estuary, within the boundaries of the city of Recife, in the State of Pernambuco in the northeast of Brazil. The total metal content was determined as well. All metals were extracted from the residual fraction at a percentage greater than 50%.

Pharmacological characterization of RMP-7, a novel bradykinin agonist in smooth muscle

RMP-7 is a bradykinin (BK) agonist designed to be resistant to kininases such as angiotensin-converting enzyme (ACE). Pharmacological assays were performed with RMP-7 in isolated guinea-pig ileum and rat mesenteric artery. RMP-7 induced contractile responses in the guinea-pig ileum, where the apparent affinity of the peptide (pD2) was significantly lower than that determined for BK (7.3 +/- 0.07 vs. 8.3 +/- 0.05, respectively). HOE-140 blocked this effect indicating that B2 receptor was involved. Captopril (1 microM) had no potentiating effect on RMP-7 but increased pD2 value determined for BK (8.8 +/- 0.1), confirming a high resistance of RMP-7 to the ACE. In rat mesenteric artery, RMP-7 induced endothelium-dependent relaxation (7.8 +/- 0.4), with a higher affinity than that of BK which induced vasodilatation only in the presence of 1 microM captopril (6.9 +/- 0.36). Nevertheless, the maximum effect induced by RMP-7 was lower than that of BK in contrast to that observed in guinea-pig ileum although B2 receptor was involved in both cases. We concluded that: RMP-7 is greatly resistant to the ACE and that the receptor sites activated by RMP-7 and BK show important differences in vascular and non-vascular preparations probably due to the different sensitivity of the B2 receptor to RMP-7.

Dengue epidemic in the State of Rio Grande do Norte, Brazil, in 1997

During 1997 a large dengue epidemic occurred in Rio Grande do Norte, a State in north-east Brazil. The co-circulation of dengue virus type 1 and dengue virus type 2 was demonstrated by virus isolation in Aedes albopictus clone C6/36 cell-line and by reverse transcriptase-polymerase chain reaction (RT-PCR). IgM capture enzyme-linked immunosorbent assay confirmed 52.3% of the 8105 studied cases and dengue antigen was demonstrated by immunohistochemical reaction on hepatocytes from 2 out of 5 fatal cases studied. Individual risk factors for development of dengue haemorrhagic fever/dengue shock syndrome, such as hypertension, diabetes mellitus and bronchial asthma, are discussed.

Semileaky waves in dielectric chirowaveguides

The occurrence of semileaky waves in dielectric chirowaveguides is investigated. It is shown that a thinfilm dielectric chiroslabguide with an achiral superstrate and in which both the film and substrate are chiral can support semileaky modes radiating energy into the substrate, provided that the chirality parameters are properly chosen.

Two pregnancies in a Cushing's syndrome. Case report

A case of patient with Cushing's syndrome due to an adrenal adenoma who conceived twice in the course of the disease is described. Pregnancy is known to be rare in these patients. When first seen she had some manifestations of Cushing's syndrome, but follow-up was lost prior to complete investigation. She conceived a few months later and gave birth to a 900 g premature liveborn infant. At the beginning of a second pregnancy, an adrenal adenoma was resected. The remainder of her pregnancy was uneventful and she delivered a normal fullterm 4 kg infant. Both children show normal physical and neurological development up to date. The patient presented herein illustrates the early diagnosis of Cushing's syndrome during pregnancy is extremely important, and early surgical treatment is indicated in order to avoid maternal and fetal complications.