Ultrastructure and expression of enzymes: cytochrome P450 aromatase and cytochrome P450c17 (17-α-hydroxylase/17,20-lyase) in different developmental stages of spermatogenesis and excurrent canals in agouti (Dasyprocta sp.) kept in captivity

Espécies silvestres com grande potencial zootécnico devem ser exploradas de forma racional a fim de se evitar a extinção das mesmas. Assim se dá a importância de pesquisas voltadas à reprodução daquelas criadas em cativeiro, como a cutia (Dasyprocta sp.). Este animal é um mamífero e roedor vivente, em sua maioria, na Caatinga brasileira. A ultraestrutura é a base para determinar os estágios celulares e, assim, facilitar as comparações dos processos entre cutias e roedores silvestres ou outros mamíferos. As enzimas P450 aromatase e P450c17 são responsáveis pela regulagem da produção de estrógenos e andrógenos, respectivamente. Considerando a hipótese de que o comportamento de expressão das enzimas do complexo citocromo P540 permanece o mesmo no testículo e na via espermática de cutias durante as fases de desenvolvimento sexual, objetivou-se observar a atuação das enzimas P450 aromatase e P450c17 (17-α-hidroxilase/17,20-liase) nas diferentes fases do desenvolvimento sexual, detalhar a ultraestrutura dos componentes desta via e constatar o desenvolvimento do processo espermatogênico. Segmentos do ducto deferente, epidídimo e testículo de 28 cutias machos em diferentes idades (um dia, 2-14 meses) foram fixados em paraformoldeído e glutaraldeído. O material foi coletado no Centro de Multiplicação da Universidade Federal Rural do Semiárido, Mossoró, RN (Autorização IBAMA nº 2028236/2008). Foram feitos: histologia, seguindo o protocolo padrão para hematoxilina e eosina; processamento para corte semifino (azul de toluidina); microscopia eletrônica de transmissão e varredura; e imunohistoquímica. Este trabalho foi pioneiro ao observar que o epidídimo de cutias é composto por células basais, células principais, células haloides e, quando impúbere, por células \"limpas\", e por células apicais, quando a partir da puberdade. O ducto deferente de cutias antes da puberdade era caracterizado por duas camadas musculares, possivelmente devido à falta de trânsito espermático. No epitélio germinativo foram encontradas, em sua maioria, células em prófase I, principalmente em paquíteno. A espermiogênese é completa quando na pré-puberdade, entretanto, a espermiação ocorre a partir dos 9 meses de idade. A expressão da enzima P450 aromatase variou ao longo do desenvolvimento sexual, sendo na puberdade seu pico de atividade. A P450c17 não mostrou nenhuma ação em qualquer fase sexual. Pode-se concluir que o epitélio germinativo testicular e intersticial, bem como o epitélio pseudoestratificado estereociliado do epidídimo e do ducto deferente de cutias criadas em cativeiro sofrem mudanças morfológicas e funcionais ao longo do desenvolvimento sexual. As atividades androgênicas preponderantes em cutias criadas em cativeiro ocorrem no período da puberdade.Wild species with great potential livestock should be explored rationally in order to prevent the extinction of the same. Thus is the importance of research aimed at reproducing those bred in captivity, such as agouti (Dasyprocta sp.). This animal is a mammal and rodent living mostly in the Brazilian Caatinga. The ultrastructure is the basis for determining the stages and thus facilitates comparisons of cases between agouti and wild rodents or other mammals. The enzymes P450 aromatase and P450c17 are responsible for regulating the production of estrogens and androgens, respectively. On the assumption that the behavior of expression of the enzymes of complex cytochrome P540 remains the same in the testis and excurrent canals of the agouti during the stages of sexual development, aimed to observe the activity of the enzymes P450 aromatase and P450c17 (17-α- hidroxilase/17,20-lyase) in different stages of sexual development, detail the ultrastructure of the components of this pathway and observe the development of spermatogenesis. Segments of the vas deferens, epididymis and testis of 28 agouti males at different ages (1 day, 2-14 months) were fixed in glutaraldehyde and paraformoldehyde. The material was collected on Center of Multiplication of Federal Rural University of the Semi-arid, Natal, RN (IBAMA Authorization No. 2028236/2008). Were made: histology following the standard protocol for hematoxylin and eosin; processing to semithin (blue toluidine), electron microscopy of transmission and scanning; and immunohistochemistry. This work was pioneered by observing that the epididymis is composed by basal cells, principal cells, haloids cells; and for clean cells when impubertal and apical cells after puberty in agoutis. The vas deferens before puberty was characterized by two muscle layers, possibly due to the lack of sperm transit. In the germinal epithelium were found mostly cells in prophase I, mainly in pachytene. Spermiogenesis is complete when prepubertal phase; however, spermiation takes place from 9 months of age. The expression of enzymes of the cytochrome complex varied over sexual development and peak activity of P450 aromatase was at puberty. The P450c17 showed no action at any stage of sexual development. It can be concluded that the testicular germinal epithelium and interstitial epithelium as well as the pseudostratified estereociliated epithelium of the epididymis and vas deferens undergo morphological and functional changes during the sexual development. Androgenic activities prevalent in agoutis kept in captivity occur during puberty

Effect of letrozole in hypothalamus and gonads of spixs yellow-toothed cavy during sexual development

O letrozol é usado como terapêutico em desordens reprodutivas provocadas pelos altos níveis de estrógenos. A enzima citocromo P450 aromatase biossintetiza estrógenos a partir dos andrógenos em tecidos com capacidade esteroidogênica, como o cérebro, testículo e ovário. O objetivo do nosso estudo foi avaliar se o letrozol afeta o desenvolvimento das principais vias de controle reprodutivo de preás machos e fêmeas. Para tanto, consideramos o ganho de peso corporal, do testículo, do ovário e do cérebro, a progressão morfológica da espermatogênese e da foliculogênese, bem como a atividade enzimática da citocromo P450 aromatase nesses tecidos, comparado-os entre os grupos experimentais de machos e fêmeas. Os preás receberam 0,01 g/kg-1 de letrozol diluído, via oral, semanalmente, até as idades de 30, 45, 90 e 120 dias. O letrozol aumentou o ganho de peso corporal, das gônadas e do cérebro. Também, prejudicou a formação do epitélio germinativo testicular e estratificou o epitélio de revestimento do ovário. Ainda, o inibidor pode alterar os campos neurais relacionados às zonas de aromatização. E alterou os sítios de atuação da aromatase nas gônadas. Concluímos que o uso prolongado do letrozol pode ocasionar efeito anabólico, infertilidade de machos, induzir a displasia ovariana em fêmeas e alterar os sítios de atuação da aromatase.Letrozole is used as a therapeutic in reproductive disorders caused by high estrogen levels. The enzyme cytochrome P450 aromatase biosynthesizes estrogens from androgens on tissues with steroidogenic capacity such as brain, testis and ovary. The objective of our study was to evaluate whether letrozole affects the development of the main reproductive control pathway of male and female spixs yellow-toothed cavy. For this, we considered body weight, testis, ovary and brain gain, spermatogenesis and folliculogenesis, as well as the enzymatic activity of cytochrome P450 aromatase in these tissues compared to experimental groups of males and females. The cavies received dilute letrozole orally (0,01 g/kg-1), once a week, until 30, 45, 90 and 120 days. Letrozole increased body weight, gonad and brain gain. Also, it impaired the formation of the testicular germinal epithelium and epithelium of ovary. Furthermore, the inhibitor may alter the neural fields related to the aromatization zones and changed the sites of aromatase in the gonads. We concluded that prolonged use of letrozole may result in an anabolic effect, male infertility, induce ovarian dysplasia in females, and alter the sites of aromatase activity

Effect of letrozole in hypothalamus and gonads of spixs yellow-toothed cavy during sexual development

O letrozol é usado como terapêutico em desordens reprodutivas provocadas pelos altos níveis de estrógenos. A enzima citocromo P450 aromatase biossintetiza estrógenos a partir dos andrógenos em tecidos com capacidade esteroidogênica, como o cérebro, testículo e ovário. O objetivo do nosso estudo foi avaliar se o letrozol afeta o desenvolvimento das principais vias de controle reprodutivo de preás machos e fêmeas. Para tanto, consideramos o ganho de peso corporal, do testículo, do ovário e do cérebro, a progressão morfológica da espermatogênese e da foliculogênese, bem como a atividade enzimática da citocromo P450 aromatase nesses tecidos, comparado-os entre os grupos experimentais de machos e fêmeas. Os preás receberam 0,01 g/kg-1 de letrozol diluído, via oral, semanalmente, até as idades de 30, 45, 90 e 120 dias. O letrozol aumentou o ganho de peso corporal, das gônadas e do cérebro. Também, prejudicou a formação do epitélio germinativo testicular e estratificou o epitélio de revestimento do ovário. Ainda, o inibidor pode alterar os campos neurais relacionados às zonas de aromatização. E alterou os sítios de atuação da aromatase nas gônadas. Concluímos que o uso prolongado do letrozol pode ocasionar efeito anabólico, infertilidade de machos, induzir a displasia ovariana em fêmeas e alterar os sítios de atuação da aromatase.Letrozole is used as a therapeutic in reproductive disorders caused by high estrogen levels. The enzyme cytochrome P450 aromatase biosynthesizes estrogens from androgens on tissues with steroidogenic capacity such as brain, testis and ovary. The objective of our study was to evaluate whether letrozole affects the development of the main reproductive control pathway of male and female spixs yellow-toothed cavy. For this, we considered body weight, testis, ovary and brain gain, spermatogenesis and folliculogenesis, as well as the enzymatic activity of cytochrome P450 aromatase in these tissues compared to experimental groups of males and females. The cavies received dilute letrozole orally (0,01 g/kg-1), once a week, until 30, 45, 90 and 120 days. Letrozole increased body weight, gonad and brain gain. Also, it impaired the formation of the testicular germinal epithelium and epithelium of ovary. Furthermore, the inhibitor may alter the neural fields related to the aromatization zones and changed the sites of aromatase in the gonads. We concluded that prolonged use of letrozole may result in an anabolic effect, male infertility, induce ovarian dysplasia in females, and alter the sites of aromatase activity

Main causes of mortality in Holstein calves on rural properties in the Bragantina region

This study was conducted on two dairy farms that breed Holstein cattle in the municipality of Bragança Paulista, São Paulo. The study included 11 female calves that were one to three months old. The animals were autopsied. Tissue samples of affected organs were collected for histopathological and microbiological examination and blood was collected for serological tests. The aim of this study was to identify the main causes of death in calves of dairy cattle from the Bragantina region. Among the causes, the frequency of dysentery and respiratory diseases was similar. The samples evalulated identified a higher frequency of macroscopic and microscopic lung lesions when compared to intestinal lesions. The etiological agents associated with the diseases found were Salmonella sp., Escherichia coli, Clostridium perfringens, Pasteurella spp., syncytial virus and coronavirus, which affect the respiratory and gastrointestinal systems and can lead to septicemia and death

Mesenchymal stem cells: emphasis in adipose tissue

The study of stem cells has evolved rapidly in recent decades. The importance is given to the concept that these cells are potentially able to become any cell type and have the power of self-renewal throughout the life of the organism. Mesenchymal stem cells (MSCs) can be isolated from various organs of the body such as bone marrow, adipose tissue, synovium, muscle and dermis, deciduous teeth, umbilical cord, placenta, liver, spleen and thymus. After their isolation in vitro, mesenchymal stem cells have the capacity to differentiate into various mesenchymal lineages and various tissues after the use of appropriate cultures. Studies have reported that mesenchymal stem cells from adipose tissue have the potential to differentiate themselves, like the cells commonly studied bone marrow. Adipose tissue is attractive due to its easy access, rapid expansion in vitro and only one collects the large amount of tissue. This review intends to show the protocols for isolation, cell culture and means of commercial cellular differentiation most widely used with emphasis on adipose tissue

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data

NEOTROPICAL XENARTHRANS: a data set of occurrence of xenarthran species in the Neotropics

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data