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RESUMO Objetivou-se avaliar a qualidade microbiológica da carne bovina moída por meio de um estudo metanalítico. Para o estudo metanalítico, utilizou-se como base de dados o Google Scholar Brasil, concentrando-se no período de busca entre outubro de 2020 e junho de 2021. Foram avaliados 108 estudos científicos com as variáveis analisadas referentes a contagens de bactérias mesófilas, bactérias psicrotróficas, coliformes totais, coliformes termotolerantes, Staphylococcus aureus e Salmonella sp. em unidade formadora de colônia por grama de carne (UFC.g-1). Os dados foram submetidos a uma análise descritiva e distribuição normal por histograma de frequência. As contagens de bactérias mesófilas apresentaram uma média de 3,09 UFC.g-1 com coeficiente de variação de 68,53%. As bactérias psicrotróficas apresentaram 27,27% dos dados levantados próximos a 5,60 UFC.g-1. Com relação aos coliformes termotolerantes, 40% dos dados levantados estavam com contagens entre 0,90 e 40% em 3,10 UFC.g-1. Oito estudos apresentaram efeitos (P < 0,001) sobre a presença se Salmonella sp. na carne moída, sendo este estudo metanalítico classificado como heterogêneo (Chi2 = 80,39; P < 0,001) e com inconsistência alta (I2 = 81%). A metanálise constatou baixa contagem de bactérias mesófilas e Staphylococcus aureus em pesquisas brasileiras que abordassem a qualidade microbiológica da carne moída bovina. Estudos metanalíticos como o proposto são necessários para identificar os problemas relacionados à transmissão de doenças em alimentos. Observou-se que, nos achados brasileiros, Staphylococcus aureus e mesófilos foram encontrados em menor quantidade, com maior presença de Samonella sp.

ABSTRACT This paper evaluates the microbiological quality of ground beef through a meta-analytic study using Google Scholar Brazil database, with a focus on the search period between October 2020 and June 2021. A total of 108 scientific studies were evaluated with the analyzed variables, referring to the counts of mesophilic bacteria, psychrotrophic bacteria, total coliforms, thermotolerant coliforms, Staphylococcus aureus and Salmonella sp. In colony forming unit per gram of meat (CFU.g-1). Data were subjected to descriptive analysis and normal distribution by frequency histogram. The counts of mesophilic bacteria presented an average of 3.09 CFU.g-1, with a coefficient of variation of68.53%. Psychrotrophic bacteria represented 27.27% of the data collected, close to 5.60 CFU.g-1. Regarding thermotolerant coliforms, 40% of the data collected had counts between 0.90 and 40% at 3.10 CFU.g-1. Eight studies showed effects (p < 0.001) on the presence of Salmonella sp. in ground beef. This meta-analytic study was classified as heterogeneous (Chi2 = 80.39; p < 0.001) and with high inconsistency (P = 81%). Besides, the meta-analysis allowed identifying low counts of mesophilic bacteria and Staphylococcus aureus in Brazilian studies addressing the microbiological quality of ground beef.

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Vitamin D deficiency is considered a global public health problem with high prevalence in children and adolescents. The majority of the studies in the literature have identified a relationship between vitamin D insufficiency/deficiency and obesity, as well as other traditional cardiometabolic risk factors in children and adolescents. Scarce studies address vitamin D status with oxidative stress and inflammation in the young population. The aim of this systematic review was to evaluate the evidence of the association of vitamin D status with oxidative stress and inflammation in children and adolescents. This is a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guideline on reporting systematic reviews. Eight studies were selected for this review. All included studies evaluated inflammatory biomarkers and two out of eight evaluated biomarkers of oxidative stress. The majority of the studies (five out of eight) found association of vitamin D status with biomarkers of oxidative stress and inflammation such as C-reactive protein (CRP), interleukin-6 (IL-6), cathepsin S, vascular cell adhesion molecule-1 (VCAM-1), malondialdehyde (MDA), myeloperoxidase, 3-nitrotyrosine, and superoxide dismutase (SOD). Vitamin D status is associated with oxidative stress and inflammation in the majority of the studies with children and adolescents. Thus, the assessment of vitamin D status is important because it is associated with nontraditional cardiometabolic markers in the pediatric population (review registration: PROSPERO CRD42018109307).

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The prion protein (PrPC) binds copper and affects copper metabolism, albeit among a poorly understood functional landscape. Much of the data on physiological roles of PrPC were obtained in mice of mixed genetic background deficient of the PrPC-coding gene Prnp. This strategy is currently under scrutiny due to the flanking gene problem, in particular related with a polymorphism, typical of both the 129Sv and 129Ola mouse substrains, in the Sirpa gene located in the vicinity of Prnp. Here we report an investigation of biochemical properties of Cu(I)-ATPases as a function of genotype in two strains of PrPC-deficient mice. We found that both the brain and liver of Prnp-null mice of mixed B6;129Sv background had diminished activity, accompanied by increased catalytic phosphorylation of Cu(I)-ATPase, as compared with the respective wild-type animals. However, no such differences were found between Prnp-null and wild-type mice of a B10;129Ola background. Activity of Cu(I)-ATPase was strongly reduced in brain tissue from mice of 129Sv strain, when compared with wild-type either of B6;129Sv, and especially of mice of the B6 strain. No differences between wild-type and Prnp-null brain tissue were noted in the expression of either Atp7a or b genes, and RFLP analysis indicated that the Sirpa129 polymorphism was present in both the B6;129Sv and B10;129Ola Prnp-null mouse colonies used in this study. The results suggest a novel substrain-dependent effect of 129Sv, but not 129Ola, genotype upon the regulation of the Cu(I)-ATPase catalytic cycle in Prnp-null mice, rather than either a Prnp-dependent, or a 129 strain-dependent effect.

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RESUMORubiaceae é uma família botânica com grande potencial químico e biológico Neste trabalho realizou-se a prospecção fitoquímica e avaliou-se as atividades citotóxica, antioxidante e antifúngica dos extratos diclorometânicos e metanólicos das folhas de Duroia saccifera, Ferdinandusa goudotiana, F. hirsuta, F. paraensis, Ferdinandusa sp., Palicourea corymbifera e P. guianensis. A avaliação da citotoxicidade foi realizada empregando-se o ensaio de toxicidade sobre Artemia salina. A atividade antifúngica foi determinada pelo método de difusão em ágar utilizando-se os fungos: Epidermophyton floccosum, Microsporum canis 32905, M. gipseum 29/00, Trichophyton mentagrophytes ATCC 9533/03, T. rubrum ATCC 28189, T. tonsurans 21/97, Cladosporium cladosporioides, C. sphaerospermum, FusariumU. 662/06, Scytalidium U. 661/06, Candida albicans ATCC 3632 e C. albicans U. 5/99. A atividade antioxidante foi determinada através dos ensaios de redução do radical livre 1,1-difenil-2-picrilhidrazila (DPPH) e de descoloração do cátion radical ácido-6-sulfônico-2,2-azinobis-3-etilbenzotiazolina (ABTS). Para o ensaio de toxicidade sobre A. salina observou-se maior toxicidade no extrato metanólico de F. goudotiana, que se mostrou tóxico até a concentração de 5 µg mL-1. A presença de princípios antifúngicos foi observada em F. hirsuta e F. paraensiscontra quatro dos fungos testados. Na avaliação da atividade antioxidante os extratos metanólicos mostraram maior atividade que os extratos diclorometânicos, sendo coincidente o resultado obtido através de ambos os métodos (redução do DPPH e descoloração do ABTS). Os resultados criam possibilidades para futuras investigações relacionadas à estrutura e atividade dos componentes de cada extrato ativo.

ABSTRACTRubiaceae is a plant family with great chemical and biological potential. In this work a phytochemical prospection was performed and it was assessed the cytotoxic, antioxidant and antifungal activities of dichloromethanic and methanolic extracts of the leaves of Duroia saccifera, Ferdinandusagoudotiana, F. hirsuta, F. paraensis, Ferdinandusa sp., Palicourea corymbifera and P. guianensis. The cytotoxicity evaluation was carried out using the test toxicity on Artemia salina. The antifungal activity was determined by agar diffusion method using fungi: Epidermophyton floccosum, Microsporum canis 32905, M. gipseum 29/00, Trichophyton mentagrophytes ATCC 9533/03, T.rubrum ATCC 28189, T. tonsurans 21/97 , Cladosporium cladosporioides, C. sphaerospermum, FusariumU. 662/06, Scytalidium U. 661/06, Candida albicans ATCC 3632 and C. albicans U. 5/99. The antioxidant activity was determined by testing the amount of free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the discoloration of the radical cation 6-sulfonic acid-2 ,2-azinobis-3-ethylbenzothiazoline (ABTS). For the toxicity test on A. salina greater toxicity in the methanol extract of F. goudotiana was observed, which proved to be toxic up to a concentration of 5 µg mL-1. The presence of antifungal principles was observed in the F. hirsuta and F. paraensis against four tested fungi. In the evaluation of the antioxidant activity, the methanol extracts showed greater activity than the dichloromethanic ones, being similar the obtained result through both methods (reduction of DDPH and ABTS decolorization) . The results create possibilities for future researches related to the structure and activity of the components of each active extract.

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The aim of this study was to analyse the composition, structure and spatial and temporal patterns of diversity and abundance of the ichthyofauna of the Santa Cruz Reservoir in semi-arid Brazil. Data were collected quarterly at eight sampling locations on the reservoir between February 2010 and November 2011 using gillnets from 12- to 70-mm mesh that were left in the water for 12h00min during the night. We evaluated the composition, structure and assemblage descriptors (Shannon-Wiener diversity index and equitability, respectively) and catch per unit effort by the number (CPUEn) and biomass (CPUEb) of the ichthyofauna. The 6,047 individuals (399,211.6 g) captured represented three orders, ten families and 20 species, of which four belonged to introduced species. The family Characidae was the most abundant with a total of 2,772 (45.8%) individuals captured. The species-abundance curve fit the log-normal model. In the spatial analysis of diversity, there were significant differences between sampling sites in the lacustrine and fluvial regions, and the highest values were found in the lacustrine region. In the temporal analysis of diversity, significant differences were also observed between the rainy and dry seasons, and the higher values were found during the dry season. Equitability followed the same spatiotemporal pattern as diversity. The Spearman correlation was significantly negative between diversity and rainfall. A cluster analysis spatially separated the ichthyofauna into two groups: one group formed by sampling sites in the fluvial region and another group formed by the remainder of the points in the lacustrine region. Both the CPUEn and CPUEb values were higher at point 8 (fluvial region) and during the rainy season. A two-way ANOVA showed that the CPUEn and CPUEb values were spatially and temporally significant. We conclude that the spatial and temporal trends of diversity in the Santa Cruz reservoir differ from those of other Brazilian reservoirs but that the fish community composition and spatiotemporal patterns of abundance were similar.

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The aim of this study was to analyse the composition, structure and spatial and temporal patterns of diversity and abundance of the ichthyofauna of the Santa Cruz Reservoir in semi-arid Brazil. Data were collected quarterly at eight sampling locations on the reservoir between February 2010 and November 2011 using gillnets from 12- to 70-mm mesh that were left in the water for 12h00min during the night. We evaluated the composition, structure and assemblage descriptors (Shannon-Wiener diversity index and equitability, respectively) and catch per unit effort by the number (CPUEn) and biomass (CPUEb) of the ichthyofauna. The 6,047 individuals (399,211.6 g) captured represented three orders, ten families and 20 species, of which four belonged to introduced species. The family Characidae was the most abundant with a total of 2,772 (45.8%) individuals captured. The species-abundance curve fit the log-normal model. In the spatial analysis of diversity, there were significant differences between sampling sites in the lacustrine and fluvial regions, and the highest values were found in the lacustrine region. In the temporal analysis of diversity, significant differences were also observed between the rainy and dry seasons, and the higher values were found during the dry season. Equitability followed the same spatiotemporal pattern as diversity. The Spearman correlation was significantly negative between diversity and rainfall. A cluster analysis spatially separated the ichthyofauna into two groups: one group formed by sampling sites in the fluvial region and another group formed by the remainder of the points in the lacustrine region. Both the CPUEn and CPUEb values were higher at point 8 (fluvial region) and during the rainy season. A two-way ANOVA showed that the CPUEn and CPUEb values were spatially and temporally significant. We conclude that the spatial and temporal trends of diversity in the Santa Cruz reservoir differ from those of other Brazilian reservoirs but that the fish community composition and spatiotemporal patterns of abundance were similar.(AU)

O objetivo desse trabalho foi analisar a composição, estrutura e os padrões espacial e temporal de diversidade e abundância da ictiofauna do reservatório de Santa Cruz, no semiárido brasileiro. As coletas ocorreram trimestralmente em oito pontos do reservatório entre fevereiro de 2010 e novembro de 2011, com rede de espera e malhas entre 12 a 70mm, expostas por 12h00min na água no período noturno. Foram analisados a composição, estrutura e os descritores da assembleia (índice de diversidade de Shannon-Wiener, equitabilidade), CPUEn (número) e CPUEb (biomassa) da ictiofauna. Foram capturados 6.047 indivíduos (399.211,6g) pertencentes a três ordens, 10 famílias e 20 espécies, sendo quatro espécies introduzidas. A família Characidae foi a mais abundante com 2.772 (45,8%) dos indivíduos capturados. A curva de abundância-espécie se ajustou ao modelo log-normal. Na abordagem espacial da diversidade, houve diferenças estatísticas entre os pontos da região fluvial e região lacustre, sendo os maiores valores encontrados nos pontos da região lacustre. Na abordagem temporal da diversidade, também foram observados diferenças estatísticas entre as estações de chuva e seca, sendo os maiores valores encontrados na estação da seca. A equitabilidade seguiu o mesmo padrão espaço-temporal da diversidade. A correlação de Spearman foi significativa e negativa entre a diversidade e a pluviosidade. A análise de cluster separou espacialmente a ictiofauna em dois grupos: um formado pelos pontos da região fluvial e outro formado pelos demais pontos do compartimento lacustre. Tanto as valores da CPUEn e CPUEb foram maiores no ponto 8 (compartimento fluvial) e na estação da chuva. ANOVA two-way foi significativa no espaço e no tempo nos valores da CPUEn e CPUEb. Concluímos que os padrões espacial e temporal de diversidade no reservatório de Santa Cruz foram diferentes de outros reservatórios brasileiros, enquanto a composição da ictiofauna e os padrões espaço-temporal de abundância apresentaram padrões similares.(AU)

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The aim of this study was to compare the efficacy of two extenders (Tris-egg yolk - TRIS and Botu-Bov® - BB, Botupharma, Brazil) for bovine semen cryopreservation with a different number of sperm per straw (6, 12, 25 or 50 x 106 sperm per straw) on post-thaw seminal viability (experiment 1) and pregnancy per artificial insemination (P/AI; experiment 2). In experiment 1, higher values of linearity and straightness associated to low amplitude of lateral head displacement (ALH) were observed in samples cryopreserved with BB extender, when compared to samples cryopreserved with TRIS extender (P < 0.05) regardless of the sperm concentration per straw. The pregnancy rates were 57.63, 60.32, 59.26 and 62.50% respectively for 6, 12, 25 or 50 x 106 sperm/straw in BB samples and 45.61, 48.84, 60.34 and 70.59% respectively for the TRIS extender. Increasing the number of sperm had a significant effect on P/AI (P < 0.05) when TRIS extender was used. In conclusion, Botu-Bov® extender promotes better post-thaw sperm movement. The increase in the number of sperm cells per insemination dose improved P/AI rates in Bos indicus lactating beef cows inseminated when using Tris-egg yolk extender.

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The aim of this study was to compare the efficacy of two extenders (Tris-egg yolk - TRIS and Botu-Bov® - BB, Botupharma, Brazil) for bovine semen cryopreservation with a different number of sperm per straw (6, 12, 25 or 50 x 106 sperm per straw) on post-thaw seminal viability (experiment 1) and pregnancy per artificial insemination (P/AI; experiment 2). In experiment 1, higher values of linearity and straightness associated to low amplitude of lateral head displacement (ALH) were observed in samples cryopreserved with BB extender, when compared to samples cryopreserved with TRIS extender (P < 0.05) regardless of the sperm concentration per straw. The pregnancy rates were 57.63, 60.32, 59.26 and 62.50% respectively for 6, 12, 25 or 50 x 106 sperm/straw in BB samples and 45.61, 48.84, 60.34 and 70.59% respectively for the TRIS extender. Increasing the number of sperm had a significant effect on P/AI (P < 0.05) when TRIS extender was used. In conclusion, Botu-Bov® extender promotes better post-thaw sperm movement. The increase in the number of sperm cells per insemination dose improved P/AI rates in Bos indicus lactating beef cows inseminated when using Tris-egg yolk extender.(AU)

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This study aimed to assess outcomes of expectant management for early preterm premature rupture of membranes (PPROM). This retrospective cohort involved 66 women with PPROM <28 weeks managed in a single hospital (1999-2006). Main outcomes were chorioamnionitis, severe maternal morbidity (maternal sepsis, haemorrhage/blood transfusion, hysterectomy or admission to intensive care unit), maternal mortality, low birth weight, preterm birth, neonatal infection and perinatal mortality. Mean gestational ages at PPROM and delivery were 21.7 ± 4.2 and 28.4 ± 5.9 weeks, respectively. Chorioamnionitis was diagnosed in 47%; no cases of severe maternal morbidity or mortality occurred. Stillbirth rate was 25.7% and >80% of infants were delivered before 34 weeks. Neonatal infection was diagnosed in 42.9% of the 49 live-births. Overall survival rate was 57.6%. Expectant management of PPROM <28 weeks resulted in high rates of chorioamnionitis and preterm deliveries but in over half of the cases, a live infant was discharged home.

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This study examines the qualitative and quantitative aspects of fishery landings at the hypereutrophic Barra Bonita reservoir, Brazil. Data were collected each month (July/2004-June/2006) at three localities and the reported catch, fishing effort and fishing techniques were recorded from 745 landings, comprising a total fish catch of 86,691.9 kg. The most caught species were exotic tilapias, especially the Nile tilapia (Oreochromis niloticus L.), which represented 82.5 percent of the total biomass. The reservoir's fishery productivity was 11.1 kg/ha-¹/day-¹ with a Catch Per Unit Effort of 62.4 kg/fisher-¹/day-¹. Five fishing techniques were identified: cast net, gill net, trawl net, beating gill net, and beating gill net + gill net. The analysis of DCA related the active strategies for the tilapia catch, to the passive strategies for the Pimelodus maculatus (Lacepède) and Triportheus angulatus catches (Spix & Agassiz), and the mixed strategies for the tilapia, catfish and Prochilodus lineatus (Valenciennes) catches. ANCOVA results were significant for all the variables analysed (season, fishing location and fishing technique). The results showed that fishing for "corvina" Plagioscion squamosissimus (Heckel), predominant in the 1990s, had been replaced by fishing focused on the Nile tilapia. This substitution appears to be due to the increasing levels of eutrophication in the reservoir, combined with changes in fishing techniques. The pattern of the fisheries in Barra Bonita Reservoir follow those in other eutrophic Brazilian reservoirs, with catches of the exotic Nile tilapia predominating.

Esse estudo avaliou aspectos quantitativos qualitativos do desembarque pesqueiro no reservatório hipertrófico de Barra Bonita. Os dados foram coletados mensalmente (julho/2004-junho/2006) em três localidades e informações sobre captura, esforço de pesca e técnicas de pesca foram registrados de 745 desembarques, totalizando 86.691,9 kg de pescado capturados. As espécies mais capturadas foram as exóticas tilápias, especialmente a tilápia-do-nilo (Oreochromis niloticus L.), que representaram 82,5 por cento da biomassa total. A produtividade pesqueira do reservatório foi de 11,1 kg/ha-¹/dia-¹ com uma Captura Por Unidade de Esforço de 62,4 kg/pescador-¹/dia-¹ . Cinco técnicas de pesca foram identificadas: tarrafas, rede de espera, rede de arrasto, pesca da batida e pesca da batida + rede de espera. Análise de DCA relacionou as estratégias ativas com a captura de tilápia, as estratégias passivas com a captura de Pimelodus maculatus (Lacepède) e Triporthues angulatus (Spix & Agassiz) e a estratégia mista com a captura de tilápia, cascudos e Prochilodus lineatus (Valenciennes). Os resultados da ANCOVA foram significativos para todas as variáveis analisadas (época, local de pesca e técnicas de pesca). Os resultados mostram uma substituição da pesca da corvina, Plagioscion squamossisimus (Heckel) na década de 1990, pela tilápia-do-nilo. A substituição pode ter sido provocada pelo aumento da eutrofização do reservatório, aliado à mudança das estratégias de pesca. A pesca no reservatório de Barra Bonita seguiu padrões de outros reservatórios eutrofizados brasileiros, com a pesca sustentada pela exótica tilápia-do-nilo.

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There is some evidence to show a possible role of guanosine in the modulation of cellular function, in particular, in the neuronal system. However, nothing is known about the role of guanine in renal function. The aim of the present work was to investigate the role of guanine on modulation of Na+-ATPase activity in isolated basolateral membrane (BLM) of the renal cortex. Guanine inhibited the enzyme activity in a dose-dependent manner with maximal effect (56%) obtained at 10⁻6 M. This effect was reversed by DPCPX (8-cyclopentyl-1,3-dipropylxanthine), an antagonist of A1 receptors, but it was not changed by 10⁻8 M DMPX (3,7-dimethyl-1-propargylxanthine) or 10⁻8 M MRS (2,3-diethyl-4,5-dipropyl-6-phenylpyridine-3-thiocarboxylate-5-carboxylate), antagonists of A2 and A3 receptors, respectively. Furthermore, it was observed that guanine increased [γ-³5S]GTP-specific binding with the maximal effect observed at 10⁻6 M and this effect was abolished by 10⁻6 M GDPßS. The inhibitory effect of 10⁻6 M guanine on Na+-ATPase activity was reversed by 10⁻6 M GDPßS, 10⁻6 M forskolin, 10⁻6 M pertussis toxin and 10⁻8 M cholera toxin. These results indicate that guanine binds to a DPCPX-sensitive receptor promoting the activation of Gi protein and leading to a decrease in cAMP level and, consequently, inhibition of BLM Na+-ATPase activity.

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The purpose of this work was to apply a simple method for acquisition of power output (PO) during the Wingate Anaerobic Test (WAnT) at a high sampling rate ( S(R)) and to compare the effect of lower S(R) on the measurements extracted from the PO. 26 male subjects underwent 2 WAnTs on a cycle ergometer. The reference PO was calculated at 30 Hz as a function of the linear velocity, the moment of inertia and the frictional load. The PO was sampled at 0.2, 0.5, 1, 2 and 5 Hz. Both the peak (16.03±2.22 W·kg (-1)) and mean PO (10.34±1.01 W·kg (-1)) presented lower relative values when the S(R) was lower. Peak PO was attenuated by 0.29-42.07% for decreasing sampling rates, resulting in different values for 0.2 and 1 Hz ( P<0.001). When the S(R) was 0.2 Hz, the time to peak was delayed by 53.81% ( P<0.001) and the fatigue index was attenuated by 22.12% ( P<0.001). In conclusion, due to the differences achieved here and the fact that the peak flywheel frequency is around 2.3 Hz, we strongly recommend that the PO be sampled at 5 Hz instead of 0.2 Hz in order to avoid biased errors and misunderstandings of the WAnT results.

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In the present work, we demonstrate that adenine reduced Na(+)-ATPase activity in isolated basolateral membrane (BLM) of proximal tubule in a dose-dependent manner. Adenine metabolism was ruled out by TLC analysis of the potential [(3)H]adenine derived-metabolites. Specific binding of [(3)H]adenine to isolated BLM was observed in a dose-dependent manner with K(d) and B(max) of 242.6+/-27.6 nM and 2749.9+/-104.9 fmolmg(-1), respectively. Adenine increased the [(35)S]GTPgammaS specific binding and it was completely abolished by 10(-6)M GDPbetaS (G protein inhibitor) but it was not modified by DPCPX, DMPX and MRS1523, selective antagonists for A(1), A(2) and A(3) receptors, respectively. Furthermore, the inhibitory effect of adenine on the Na(+)-ATPase activity was blocked by 10(-6)M GDPbetaS, 1 microg/ml pertussis toxin (Gi protein inhibitor), 10(-6)M foskolin (adenylyl cyclase activator) and 10(-8)M cAMP. These data demonstrate that adenine inhibits the proximal tubule Na(+)-ATPase activity through the Gi protein-coupled receptor.

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Relata-se a ocorrência de metacercárias de Diplostomum compactum (Trematoda: Diplostomidae) infectando Geophagus brasiliensis (Teleostei: Cichlidae) do reservatório de Barra Bonita, rio Tietê, estado de São Paulo, Brasil. As metacercárias foram coletadas no globo ocular, fixadas em solução de AFA e coradas com carmim. As análises morfológicas e morfométricas de cinco espécimes foram realizadas por meio do sistema computadorizado de analise de imagem. Este foi o primeiro registro da ocorrência desse parasito no reservatório de Barra Bonita e também o primeiro registro em acará Geophagus brasiliensis.

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Relata-se a ocorrência de metacercárias de Diplostomum compactum (Trematoda: Diplostomidae) infectando Geophagus brasiliensis (Teleostei: Cichlidae) do reservatório de Barra Bonita, rio Tietê, estado de São Paulo, Brasil. As metacercárias foram coletadas no globo ocular, fixadas em solução de AFA e coradas com carmim. As análises morfológicas e morfométricas de cinco espécimes foram realizadas por meio do sistema computadorizado de analise de imagem. Este foi o primeiro registro da ocorrência desse parasito no reservatório de Barra Bonita e também o primeiro registro em acará Geophagus brasiliensis.(AU)

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Both the presence of receptors for gonadal steroids in the pineal gland and in vitro observations of direct action of melatonin upon Leydig cells, inhibiting testosterone secretion, indicate a direct connection between pineal gland and gonadal function. In the present study, we used a transmission electron microscope to analyze the morphologic parameters of Leydig cells from adult Swiss outbred white mice treated with daily subcutaneous injections of 100 µg of melatonin (N-acetyl, 5-methoxytryptamine), during 22 consecutive days, compared with sham-control animals which had only received the melatonin vehicle. The melatonin group of mice showed a decrease in nuclear volume and fractional nuclear volume; smooth and rough endoplasmic reticulum; mitochondria; and Golgi complex. Our data also showed an increase in cytoplasmic volume, fractional cytoplasmic volume, and lysosomes in these same animals. The results suggest that melatonin, directly or indirectly, alters the ultrastructure of mouse Leydig cells and possibly influences their secretory activity by inhibiting their capacity to secrete steroids

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