57 resultados para Age-dependent Branching Processes with Immigration at Zero State
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It has been demonstrated that resistance exercise improves cognitive functions in humans. Thus, an animal model that mimics this phenomenon can be an important tool for studying the underlying neurophysiological mechanisms. Here, we tested if an animal model for resistance exercise was able to improve the performance in a hippocampus-dependent memory task. In addition, we also evaluated the level of insulin-like growth factor 1/insulin growth factor receptor (IGF-1/IGF-1R), which plays pleiotropic roles in the nervous system. Adult male Wistar rats were divided into three groups (N = 10 for each group): control, SHAM, and resistance exercise (RES). The RES group was submitted to 8 weeks of progressive resistance exercise in a vertical ladder apparatus, while the SHAM group was left in the same apparatus without exercising. Analysis of a cross-sectional area of the flexor digitorum longus muscle indicated that this training period was sufficient to cause muscle fiber hypertrophy. In a step-through passive avoidance task (PA), the RES group presented a longer latency than the other groups on the test day. We also observed an increase of 43 and 94% for systemic and hippocampal IGF-1 concentration, respectively, in the RES group compared to the others. A positive correlation was established between PA performance and systemic IGF-1 (r = 0.46, P < 0.05). Taken together, our data indicate that resistance exercise improves the hippocampus-dependent memory task with a concomitant increase of IGF-1 level in the rat model. This model can be further explored to better understand the effects of resistance exercise on brain functions.
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We evaluated changes in levels by comparing serum proteins in senescence-accelerated mouse-prone 8 (SAMP8) mice at 2, 6, 12, and 15 months of age (SAMP8-2 m, -6 m, -12 m, -15 m) to age-matched SAM-resistant 1 (SAMR1) mice. Mice were sacrificed, and blood was analyzed by 2-dimensional electrophoresis combined with mass spectrometry. Five protein spots were present in all SAMP8 serum samples, but only appeared in SAMR1 samples at 15 months of age except for spot 3, which also showed a slight expression in SAMR1-12 m sera. Two proteins decreased in the sera from SAMP8-2 m, -6 m, and -12 m mice, and divided into 2 spots each in SAMP8-15 m sera. Thus, the total number of altered spots in SAMP8 sera was 7; of these, 4 were identified as Ig kappa chain V region (M-T413), chain A of an activity suppressing Fab fragment to cytochrome P450 aromatase (32C2_A), alpha-fetoprotein, and apolipoprotein A-II. M-T413 is a monoclonal CD4 antibody, which inhibits T cell proliferation. We found that M-T413 RNA level was significantly enhanced in splenocytes from SAMP8-2 m mice. This agreed with serum M-T413 protein alterations and a strikingly lower blood CD4+ T cell count in SAMP8 mice when compared to the age-matched SAMR1 mice, with the latter negatively correlating with serum M-T413 protein volume. Age-related changes in serum proteins favored an increase in autoantibodies and alpha-fetoprotein and a decrease of apolipoprotein A-II, which occurred in SAMP8 mice at 2 months of age and onwards. These proteins may serve as candidate biomarkers for early aging.
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This study investigated the in vitro and in vivo antiproliferative activity of esculetin against hepatocellular carcinoma, and clarified its potential molecular mechanisms. Cell viability was determined by the MTT (tetrazolium) colorimetric assay. In vivoantitumor activity of esculetin was evaluated in a hepatocellular carcinoma mouse model. Seventy-five C57BL/6J mice were implanted with Hepa1-6 cells and randomized into five groups (n=15 each) given daily intraperitoneal injections of vehicle (physiological saline), esculetin (200, 400, or 700 mg·kg-1·day-1), or 5-Fu (200 mg·kg-1·day-1) for 15 days. Esculetin significantly decreased tumor growth in mice bearing Hepa1-6 cells. Tumor weight was decreased by 20.33, 40.37, and 55.42% with increasing doses of esculetin. Esculetin significantly inhibited proliferation of HCC cells in a concentration- and time-dependent manner and with an IC50 value of 2.24 mM. It blocked the cell cycle at S phase and induced apoptosis in SMMC-7721 cells with significant elevation of caspase-3 and caspase-9 activity, but did not affect caspase-8 activity. Moreover, esculetin treatment resulted in the collapse of mitochondrial membrane potential in vitro and in vivo accompanied by increased Bax expression and decreased Bcl-2 expression at both transcriptional and translational levels. Thus, esculetin exerted in vitro and in vivo antiproliferative activity in hepatocellular carcinoma, and its mechanisms involved initiation of a mitochondrial-mediated, caspase-dependent apoptosis pathway.
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The present study aimed to investigate visceral adipose tissue-specific serpin (vaspin) concentrations in serum and term placentas and relate these values to insulin resistance and lipid parameters in women with gestational diabetes mellitus (GDM). A total of 30 GDM subjects and 27 age-matched pregnant women with normal glucose tolerance (NGT, control) were included. Serum glucose, glycated hemoglobin (HbA1c), lipid profile, insulin, and vaspin were measured at the end of pregnancy, and homeostasis model of assessment-insulin resistance (HOMA-IR) values were calculated. Vaspin mRNA and protein levels in placentas were measured by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting, respectively. Serum vaspin levels were significantly lower in the GDM group than in controls (0.49±0.24 vs 0.83±0.27 ng/mL, respectively; P<0.01). Three days after delivery, serum vaspin levels were significantly decreased in subjects with GDM (0.36±0.13 vs0.49±0.24 ng/mL, P<0.01). However, in the GDM group, serum vaspin levels were not correlated with the parameters evaluated. In contrast, in the control group, serum vaspin levels were positively correlated with triglycerides (TG; r=0.45, P=0.02) and very low-density lipoprotein cholesterol (VLDL-C; r=0.42, P=0.03). Placental mRNA vaspin (0.60±0.32 vs0.68±0.32, P=0.46) and protein (0.30±0.08 vs0.39±0.26; P=0.33) levels in the GDM group did not differ significantly from those in the control group, but were negatively correlated with neonatal birth weight in the GDM group (r=-0.48, P=0.03; r=-0.88; P<0.01). Our findings indicated that vaspin may be an important adipokine involved in carbohydrate and lipid metabolism and may also play a role in fetal development.
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Mortality from all causes as well as from the great groups of cardiovascular diseases for the residents of the city of S.Paulo, Brazil, of the ages-group 40-69, for the years 1970 to 1983, has been analysed by means of the specific death rates. During this period a statistically significant decline was observed (28% on the average for ischemic heart diseases and 16% for cerebrovascular diseases). The death rates for the group 40-69 years old for both sexes were age-standardized and compared with those of 27 industrialized countries. The S.Paulo standardized death rates ranked almost always very high in the comparisons.
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INTRODUCTION: After the era of rubella vaccine, cytomegalovirus (CMV) infection is one of the most frequently causes of mental retardation and congenital deafness. Seroepidemiological studies are necessary to understand the transmission dynamics of the disease. The purpose of the study was to quantify the transmission rate of CMV disease in a community in the state of São Paulo, Brazil. METHODS: Using ELISA test (IgG), a retrospective serological survey looking for CMV antibodies was performed in an non-immunized community. Frozen sera from 443 individuals, randomly selected by cluster sampling technique in the town of Caieiras, São Paulo, were collected from November 1990 to January 1991. Seroprevalence was stratified by age (0-40 years). Mathematical techniques were applied to determine the age-dependent decay function of maternal antibodies during the first year of life, the age-dependent seroprevalence function and the force of infection for CMV in this community. RESULTS: It was observed a descending phase of seropositivity in the first 9 months, but changes in antibody titration were observed between 8 months old and one year of age. The average age of the first infection was 5.02 months of age and 19.84 years, when the age-dependent seroprevalence and the force of infection were analyzed between 10 months of age and 10 years of age and from 10 to 40 years old, respectively. CONCLUSION: CMV infection is highly prevalent among the population studied and infection occurs in the first year of life. This study shows that most women at reproductive age are vulnerable to the first infection, increasing the risk for congenital infection.
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Two cases of ectopic cutaneous schistosomiasis are described. Both patients presented with abdominal papular skin lesions, which on biopsy were found to contain granulomas with Schistosoma mansoni eggs. Twenty-five other cases were retrieved from the literature. Most patients were female, mean age 24.9 year, with a predominance of the white race. The most common localization was anterior thorax and abdomen. Usually, the lesions were asymptomatic. In few cases, however, severe clinical syndromes due to the parasite coexisted, such as transverse myelitis or the acute-toxemic form of the disease. Intestinal infection was not frequently demonstrated in these patients. The importance of the recognition of these cutaneous lesions may rest on the opportunity to provide an etiological diagnosis in these difficult cases.
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This study was carried out in order to obtain base-line data concerning the epidemiology of American Visceral Leishmaniasis and Chagas Disease in an indigenous population with whom the government is starting a dwelling improvement programme. Information was collected from 242 dwellings (1,440 people), by means of house to house interviews about socio-economic and environmental factors associated with Leishmania chagasi and Trypanosoma cruzi transmission risk. A leishmanin skin test was applied to 385 people and 454 blood samples were collected on filter paper in order to detect L. chagasi antibodies by ELISA and IFAT and T. cruzi antibodies by ELISA. T. cruzi seroprevalence was 8.7% by ELISA, L. chagasi was 4.6% and 5.1% by IFAT and ELISA, respectively. ELISA sensitivity and specificity for L. chagasi antibodies were 57% and 97.5% respectively, as compared to the IFAT. Leishmanin skin test positivity was 19%. L. chagasi infection prevalence, being defined as a positive result in the three-immunodiagnostic tests, was 17.1%. Additionally, 2.7% of the population studied was positive to both L. chagasi and T. cruzi, showing a possible cross-reaction. L. chagasi and T. cruzi seropositivity increased with age, while no association with gender was observed. Age (p<0.007), number of inhabitants (p<0.05), floor material (p<0.03) and recognition of vector (p<0.01) were associated with T. cruzi infection, whilst age ( p<0.007) and dwelling improvement (p<0.02) were associated with L. chagasi infection. It is necessary to evaluate the long-term impact of the dwelling improvement programme on these parasitic infections in this community.
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The goal of this short communication is to report the uncommon presence of intracellular amastigotes of Leishmania in peritoneal fluid of a dog with leishmaniasis from Alagoas State, Brazil. Physical examination of an adult male rottweiler suspected to be suffering of leishmaniasis revealed severe loss of weight, ascitis, splenomegaly, moderately enlarged lymph nodes, onychogryphosis, generalized alopecia, skin ulcers on the posterior limbs, and conjunctivitis. Samples of bone marrow, popliteal lymph node, skin ulcer, and peritoneal fluid were collected and smears of each sample were prepared and stained with hematoxylin and eosin. Numerous amastigotes were detected in bone marrow, popliteal lymph node, and skin ulcer smears. Smears of peritoneal fluid revealed the unusual presence of several free and intracellular amastigotes of Leishmania. Future studies are needed to determine whether the cytology of ascitic fluid represents a useful tool for diagnosis Leishmania infection in ascitic dogs, particularly in those living in areas where canine leishmaniasis is enzootic.
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Human Bartonellosis has an acute phase characterized by fever and hemolytic anemia, and a chronic phase with bacillary angiomatosis-like lesions. This cross-sectional pilot study evaluated the immunology patterns using pre- and post-treatment samples in patients with Human Bartonellosis. Patients between five and 60 years of age, from endemic areas in Peru, in the acute or chronic phases were included. In patients in the acute phase of Bartonellosis a state of immune peripheral tolerance should be established for persistence of the infection. Our findings were that elevation of the anti-inflammatory cytokine IL-10 and numeric abnormalities of CD4+ and CD8+ T-Lymphocyte counts correlated significantly with an unfavorable immune state. During the chronic phase, the elevated levels of IFN-γ and IL-4 observed in our series correlated with previous findings of endothelial invasion of B. henselae in animal models.
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Introduction:American tegumentary leishmaniasis (ATL) can be caused by Leishmania (Viannia) braziliensis complex. The evolution of ATL initially results in lesions and can develop into disseminated or diffuse forms. The genetic diversity of L. (V.) braziliensis in some endemic areas of Brazil has been poorly studied, such as in the state of São Paulo. This study analyzed the genetic diversity of L. (V.) braziliensis isolates collected from patients and dogs with LTA from the state of São Paulo.Methods:Leishmaniasis diagnosis was determined by PCR. The 132 biopsies were collected in different regions of Sao Paulo State, Brazil (36 municipalities). The genetic characterization of L. (V.) braziliensis isolates was tested by RFLP-PCR using DNA extracted from biopsies. The primer set amplified a specific region of Leishmania internal transcribed spacers of the ribosomal DNA locus.Results:Of the 132 samples, 52 (40%) were completely genotyped by RFLP-PCR (44 from human patients and eight from dogs). The results showed nine distinct patterns. The majority of the genotyped samples were from Sorocaba (30), and the others were distributed among 14 other municipalities. The first pattern was more frequent (29 samples), followed by pattern 2 (nine samples) and pattern 3 (three samples). Patterns 4, 6, 7, 8 and 9 were composed of two samples each and pattern 5 of one sample.Conclusion:These results suggest that polymorphic strains of L. (V.) braziliensis circulate in the state of São Paulo. These data agree with studies from other regions of Brazil, showing great variability among the natural populations of endemic foci.
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IntroductionFew studies have examined hepatocellular carcinoma (HCC) in Brazil, and the incidence and risk factors for this type of malignancy vary greatly geographically. In this paper, we report several risk factors associated with HCC diagnosed at the University Hospital in Vitória, ES, Brazil.MethodsWe reviewed 274 cases of HCC (January 1993 to December 2011) in which hepatitis B (HBV) and C (HCV) virus infection and chronic alcoholism were investigated. A diagnosis of hepatocellular carcinoma was confirmed by histology or by the presence of a characteristic pattern on imaging.ResultsHCC with associated liver cirrhosis was noted in 85.4% of cases. The mean ages of men and women were 56.6 years and 57.5 years, respectively. The male-to-female ratio was 5.8:1. Associated risk factors included the following: HBV, 37.6% (alone, 23.4%; associated with chronic alcoholism, 14.2%); HCV, 22.6% (alone, 13.5%; associated with chronic alcoholism, 9.1%), chronic alcoholism, 17.1%, non-alcoholic steatohepatitis, 2.6% and cryptogenic, 19.3%. The male-to-female ratio was higher in cases associated with HBV or chronic alcoholism compared with HCV-associated or cryptogenic cases. In 40 cases without associated cirrhosis, the male-to-female ratio and mean age were lower than those in cirrhosis-associated cases.ConclusionsThese results demonstrate that the main risk factor associated with HCC in the State of Espírito Santo is HBV. Chronic alcoholism is an important etiological factor, alone or in association with HBV or HCV infection.
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INTRODUCTION: Toxoplasma gondii infection is widely prevalent in humans and other animals worldwide. Information on the prevalence of T. gondii infection is scarce in some regions of Brazil, including riverside communities along the Amazon River basin. M METHODS: The prevalence of T. gondii in 231 people, aged 1-85 years, who were living in four riverside communities along the Purus River, Lábrea, State of Amazonas, Brazil, was determined. Antibodies against T. gondii were assayed using a commercial enzyme-linked immunosorbent assay (ELISA) kit. The hearts and brains of 50 chickens, which were raised free-range in the communities, were pooled according to the community of origin and bioassayed in mice. The isolates were genotyped using polymorphisms at 12 nuclear markers (SAG1, 5' and 3'-SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3). RESULTS: The overall seroprevalence of T. gondii was 56.7% (131/231). IgG antibodies were presented by 117 (89.3%) and IgM by 14 (10.7%) of the 131 positive individuals. No association between age group and gender with prevalence was observed (chi-square test, p > 0.05); however, the comparison between localities showed that the seroprevalence of T. gondii was significantly lower among the individuals living in the Boca do Ituxi (p < 0.05) community. Five isolates of T. gondii were obtained in the mouse bioassay, and genotyping revealed two complete genotypes that had not been described previously and three mixed isolates. CONCLUSIONS: These results support previous findings that T. gondii population genetics are highly diverse in Brazil and that T. gondii infection is active in these riverside communities.
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We report the case of a one-day-old newborn infant, female, birth weight 1900 g, gestational age 36 weeks presenting with necrotizing fasciitis caused by E. coli and Morganella morganii. The newborn was allowed to fall into the toilet bowl during a domestic delivery. The initial lesion was observed at 24 hours of life on the left leg at the site of the venipuncture for the administration of hypertonic glucose solution. Despite early treatment, a rapid progression occurred resulting in a fatal outcome. We call attention to the risk presented by this serious complication in newborns with a contaminated delivery, and highlight the site of the lesion and causal agents.
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OBJECTIVE:To assess the changes in the medicamentous treatment of elderly patients hospitalized with acute myocardial infarction occurring over an 8-year period. METHODS:We retrospectively analyzed 379 patients above the age of 65 years with acute myocardial infarction who were admitted to the coronary unit of a university-affiliated hospital from 1990 to 1997. The patients were divided into 2 groups, according to the period of time of hospital admission as follows: group 1 - from 1990 to 1993; and group 2 - from 1994 to 1997. RESULTS:The use of beta-blockers (40.8%chi 75.2%, p<0.0001) and angiotensin-converting enzyme inhibitors (42% chi59.5%, p=0.001) was significantly greater in group 2, while the use of calcium antagonists (42% chi 18.5%, p<0.0001) and general antiarrhythmic drugs (19.1% chi 10.8%, p=0.03) was significantly lower. No significant difference was observed in regard to the use of acetylsalicylic acid, thrombolytic agents, nitrate, and digitalis in the period studied. The length of hospitalization was shorter in group 2 (13.4±8.9 days chi 10.5±7.5 days, p<0.001). The in-hospital mortality was 35.7% in group 1 and 26.6% in group 2 (p=0.07). CONCLUSION: Significant changes were observed in the treatment of elderly patients with acute myocardial infarction, with a greater use of beta-blockers and angiotensin-converting enzyme inhibitors and a lower use of calcium antagonists and antiarrhythmic drugs in group 2. The length of hospitalization and the mortality rate were also lower in group 2, even though the reduction in mortality was not statistically significant.