Patterns of cell proliferation and apoptosis by topographic region in normal Bos taurus vs. Bos indicus crossbreeds bovine placentae during pregnancy

Abstract Background Placental and fetal growth requires high rates of cellular turnover and differentiation, which contributes to conceptus development. The trophoblast has unique properties and a wide range of metabolic, endocrine and angiogenic functions, but the proliferative profile of the bovine placenta characterized by flow cytometry analysis and its role in fetal development are currently uncharacterized. Complete understanding of placental apoptotic and proliferative rates may be relevant to development, especially if related to the pathogenesis of pregnancy losses and placental abnormalities. Methods In this study, the proliferation activity and apoptosis in different regions of normal bovine placenta (central and boundary regions of placentomes, placentomal fusion, microplacentomes, and interplacentomal regions), from distinct gestation periods (Days 70 to 290 of pregnancy), were analyzed by flow cytometry. Results Our results indicated that microplacentomes presented a lower number of apoptotic cells throughout pregnancy, with a higher proliferative activity by the end of gestation, suggesting that such structures do not contribute significantly to normal of placental functions and conceptus development during pregnancy. The placentome edges revealed a higher number of apoptotic cells from Day 170 on, which suggests that placentome detachment may well initiate in this region. Conclusion Variations involving proliferation and apoptotic rates may influence placental maturation and detachment, compromising placental functions and leading to fetal stress, abnormalities in development and abortion, as frequently seen in bovine pregnancies from in vitro fertilization and cloning procedures. Our findings describing the pattern of cell proliferation and apoptosis in normal bovine pregnancies may be useful for unraveling some of the developmental deviations seen in nature and after in vitro embryo manipulations

Chorioallantoic placentation in Galea spixii (Rodentia, Caviomorpha, Caviidae)

<p>Abstract</p> <p>Background</p> <p>Placentas of guinea pig-related rodents are appropriate animal models for human placentation because of their striking similarities to those of humans. To optimize the pool of potential models in this context, it is essential to identify the occurrence of characters in close relatives.</p> <p>Methods</p> <p>In this study we first analyzed chorioallantoic placentation in the prea, Galea spixii, as one of the guinea pig's closest relatives. Material was collected from a breeding group at the University of Mossoró, Brazil, including 18 individuals covering an ontogenetic sequence from initial pregnancy to term. Placentas were investigated by means of histology, electron microscopy, immunohistochemistry (vimentin, α-smooth muscle actin, cytokeration) and proliferation activity (PCNA).</p> <p>Results</p> <p>Placentation in Galea is primarily characterized by an apparent regionalization into labyrinth, trophospongium and subplacenta. It also has associated growing processes with clusters of proliferating trophoblast cells at the placental margin, internally directed projections and a second centre of proliferation in the labyrinth. Finally, the subplacenta, which is temporarily supplied in parallel by the maternal and fetal blood systems, served as the center of origin for trophoblast invasion.</p> <p>Conclusion</p> <p>Placentation in Galea reveals major parallels to the guinea pig and other caviomorphs with respect to the regionalization of the placenta, the associated growing processes, as well as trophoblast invasion. A principal difference compared to the guinea pig occurred in the blood supply of the subplacenta. Characteristics of the invasion and expanding processes indicate that Galea may serve as an additional animal model that is much smaller than the guinea pig and where the subplacenta partly has access to both maternal and fetal blood systems.</p

Morphology of the male genital organs and cloaca of Rhea americana americana

As características morfológicas, macroscópicas e microscópicas, dos órgãos genitais masculinos e da cloaca foram analisados em 23 emas, quatro filhotes (duas semanas), sete jovens (de três a oito meses) e doze adultos (três anos), provenientes da Cooperativa Emas do Brasil, RS, e do CEMAS, Mossoró, RN. Os testículos da ema possuem formato alongado e localizam-se na cavidade celomática, na região intra-abdominal dorsal, com comprimento e larguras médias de 7,6±1,2cm e 2,6± 0,7cm nos adultos; 4,5±1,5cm e 0,9±0,4cm nos jovens; e 0,8±0,3cm, e 0,2±0,1cm nos filhotes. O testículo está envolto pela túnica albugínea e seu parênquima possui túbulos seminíferos irregulares, compostos por epitélio espermatogênico e por células de sustentação, e pelo tecido intersticial, com as células endócrinas intersticiais, tecido conjuntivo frouxo e vasos. Nos adultos observaram-se todas as células da linhagem espermatogênica, enquanto nos jovens com 3 meses, os testículos apresentaram túbulos seminíferos com luz reduzidas, espermatogônias e células de sustentação indiferenciadas. Os ductos eferentes possuem um epitélio cúbico ciliado, enquanto no ducto epididimário o epitélio é columnar. O epidídimo apresentou-se alongado e fusiforme junto a margem medial do testículo. O ducto deferentes apresentou trajeto sinuoso nos adultos, retilíneo nos jovens, convoluto na sua porção média, diminuindo seu formato sigmóide em sua porção caudal, próximo à cloaca. O epitélio é pseudoestratificado e reveste a luz irregular nos adultos e circular nos jovens, mantendo proximidade com o ureter. A cloaca dividiu-se em três segmentos: o coprodeu, o urodeo e o proctodeo. No urodeu os ductos deferentes desembocaram em papilas na parede ventro-lateral, próximo a inserção do falo fibroso. O falo é um órgão fibroso linfático, localizado na parede ventral, no assoalho da cloaca, e apresentou duas porções: uma rígida bifurcada e contorcida, e outra simples espiralada e flexível, a qual normalmente esteve invertida. Em exposição forçada, o falo teve 14 cm de comprimento. De forma geral os órgãos reprodutores das emas compartilharam da morfologia de outras aves, principalmente aquelas descritas para os avestruzes.The rhea (Rhea americana americana) is a bird that belongs to the group of the Ratitas, order Rheiforme and family Rheidae. Macroscopic and microscopic morphology of the male genital organ (testes, epididymis, deferent ducts, and phallus) and the cloaca were analyzed in 23 emas, four chicken (2 weeks old), young (3 to 10 months old), and twelve adult ones (3 years old), from Cooperativa Emas do Brasil, RS and from CEMAS, Mossoró, RN. The testis of rhea had elongated shape and were located inside coelomatic cavity, in dorsal region of abdominal cavity, with medium length and width of 7.6±1.2cm and 2.6±0.7cm at adult animals; 4.5±1.5cm and 0.9±0.4cm at young animals; and 0.8±0.3cm, and 0.2±0.1cm at chicken. The testis were recovered by the tunica albuginea and its parenchyma had seminiferous tubules composed by spermatogenic epithelium and by sustentation cells, and also interstitial tissue, with interstitial endocrine cells, connective tissue and vessels. At the adult animals were observed all the cells from spermatogenic lineage, whilst at the youngs with 3 months the seminiferous tubules had a smale lumen with spermatogonia and undifferentiated sustentacular cells. The efferents ductus were composed by a cubic ciliated epithelium, while the epididimydis duct had a columnar epithelium. The epididymis was elongated and fusiform closely to medial testis board. The deferent duct had sinuous stretch at adult animals, rectilineae at young animal, convolute at its medium portion, decreasing its sigmoid shape at caudal portion, next to cloaca. The epithelium was pseudostratified ciliated, irregular lumen at adult animal, and circular at young animal, closely with urether. The cloaca was divided into three segments: coprodeum, urodeum and proctodeum. At urodeum the deferent ducts discharged into papillas at the ventral side wall, next to fibrous phallus's insertion. The phallus was a lymphatic fibrous organ, located at ventral wall, at the cloaca floor, and was composed by two portions: one rigid forked and twisted, and another simple spiraled and flexible, which normally was inverted. In forced exposition, the phallus had 14 cm in length. In a general way the Rhea genital organs shared the morphology from others birds, mainly those described to the ostrich

Expressão da progranulina durante os primeiros estágios de desenvolvimento hepático em ratos Fischer 344

Transplants are the only effective therapy for the treatment of advanced liver diseases such as cirrhosis. Given the limited number of organ donors, regenerative medicine has sought for sources of cells and tissues for replacement therapy. Embryonic stem cells are a promising source of material for transplantation because of their exclusive property of being expanded indefinitely in culture, thus, they are a source of replacement tissue. Moreover, they are capable of differentiating into practically all cell types, and may be utilized in replacement therapy in various diseases. The liver bud has bipotent stem cells that have not yet differentiated into hepatocytes or biliary duct cells; however, they have great potential of proliferation and differentiation. Thus, the challenge is to identify methods that promote their differentiation in specific and functional strains. This study aimed to evaluate the role of the progranulin growth factor PGRN during the liver development of rats F344, since this growth factor could be utilized in protocols of differentiation of stem cells of the liver bud in functional hepatocytes. The results showed that PGRN is present during different periods of hepatogenesis in F344 rats, and that this growth factor should be involved in the process of differentiation of hepatoblasts into hepatocytes after activation by HNF4α , however, PGRN seems not to exert a cellular proliferation function during the hepatogenesis. Thus, PGRN can be used in future protocols of liver cell differentiation directed toward cellular therapy in Regenerative Medicine.Os transplantes são a única terapia eficaz para o tratamento de doenças hepáticas avançadas, como a cirrose. Dado o número limitado de doadores de órgãos, a medicina regenerativa tem procurado fontes de células para a terapia de substituição. As células embrionárias são uma fonte promissora de material para o transplante devido à sua propriedade exclusiva de ser expandida indefinidamente em cultura, assim, elas são uma fonte de tecido de substituição. Além disso, são capazes de se diferenciar em praticamente todos os tipos celulares, e podem ser utilizadas na terapia de substituição em várias doenças. O broto hepático tem células-tronco (CT) bipotenciais que ainda não se diferenciam em hepatócitos ou células do ducto biliar, contudo, elas têm um grande potencial de proliferação e de diferenciação. Desse modo, o desafio é identificar métodos que promovam sua diferenciação em linhagens específicas e funcionais. Este estudo teve como objetivo avaliar o papel do fator de crescimento progranulina (PGRN) durante o desenvolvimento hepático em ratos F344, uma vez que a PGRN poderia ser utilizada em protocolos de diferenciação de CT do broto hepático em hepatócitos funcionais. Os resultados mostraram que PGRN está presente durante diferentes períodos da hepatogênese em ratos F344, e que a mesma deve estar envolvida no processo de diferenciação de hepatoblastos em hepatócitos após ativação por HNF4α, no entanto, a PGRN parece não desempenhar uma função de proliferação celular durante a hepatogênese. Assim, a PGRN pode ser usada em futuros protocolos de diferenciação de células hepáticas voltadas para a terapia celular na medicina regenerativa

Placentation and fetal membrane development in the South American coati, Nasua nasua (Mammalia, Carnivora, Procyonidae)

Abstract\ud \ud Background\ud Placental research in carnivores has concentrated on domestic species, which have zonary, labyrinthine placentas with an endotheliochorial barrier. Although the coati, Nasua nasua, is a widely distributed species in South America, data on the development of the placenta and the fetal membranes in this species are very sparse.\ud \ud \ud Findings\ud Four placentas from mid-gestation to near term were collected from wild individuals and were investigated based on gross morphology, histology, immunohistochemistry and electron microscopy. The available data support the concept that the ancestral condition of placentation in carnivores is phylogenetically characterized by a zonary and labyrinthine placental type with an endotheliochorial fetomaternal barrier, comprising extended epitheliochorial and haemochorial zones, such as hemophagous organs for iron supply and histiotrophe uptake and a yolk sac placenta.\ud \ud \ud Conclusions\ud Because of the foundational mechanisms that lead to the considerable complexity of fetomaternal contact zones in carnivores have not been studied, carnivores are interesting animal models for interhaemal barrier differentiation.Financial support was provided by FAPESP (2009/51606-0)

Placentation in Sigmodontinae: a rodent taxon native to South America

Background: Sigmodontinae, known as ""New World rats and mice,"" is a large subfamily of Cricetidae for which we herein provide the first comprehensive investigation of the placenta. Methods: Placentas of various gestational ages ranging from early pregnancy to near term were obtained for five genera, i.e. Necromys, Euryoryzomys, Cerradomys, Hylaeamys, and Oligoryzomys. They were investigated by means of histology, immunohistochemistry, a proliferation marker, DBA-lectin staining and transmission electron microscopy. Results: The chorioallantoic placenta was organized in a labyrinthine zone, spongy zone and decidua and an inverted yolk sac persisted until term. The chorioallantoic placenta was hemotrichorial. The interhemal barrier comprised fetal capillary endothelium and three layers of trophoblast, an outermost, cellular layer and two syncytial ones, with interspersed trophoblast giant cells (TGC). In addition, accumulations of TGC occurred below Reichert's membrane. The junctional zone contained syncytial trophoblast, proliferative cellular trophoblast, glycogen cells and TGC that were situated near to the maternal blood channels. In three of the genera, TGC were also accumulated in distinct areas at the placental periphery. PAS-positive glycogen cells derived from the junctional zone invaded the decidua. Abundant maternal uNK cells with positive response to PAS, vimentin and DBA-lectin were found in the decidua. The visceral yolk sac was completely inverted and villous. Conclusion: The general aspect of the fetal membranes in Sigmodontinae resembled that found in other cricetid rodents. Compared to murid rodents there were larger numbers of giant cells and in some genera these were seen to congregate at the periphery of the placental disk. Glycogen cells were found to invade the decidua but we did not identify trophoblast in the walls of the deeper decidual arteries. In contrast these vessels were surrounded by large numbers of uNK cells. This survey of wild-trapped specimens from five genera is a useful starting point for the study of placentation in an important subfamily of South American rodents. We note, however, that some of these rodents can be captive bred and recommend that future studies focus on the study of time dated pregnancies.This research was supported by grants from FAPESP (Proc. 07/51491-3 and\ud 09/53392-8)

There are differences in hematological and biochemical parameters between carriers and not carriers of experimental model of GRMD (Golden Retriever Muscular Dystrophy)?

A proposta deste estudo foi avaliar se existem alterações nos padrões hematológicos e bioquímicos de cadelas da raça Golden Retriever portadoras do gene da distrofia muscular progressiva em comparação aos valores obtidos em cadelas não portadoras de mesma raça e idade. Foram analisados 33 animais, distribuídos em dois grupos, um composto por 19 cadelas Golden Retrievers não portadoras (GRNP) e outro composto por 14 cadelas Golden Retrievers portadoras do gene da distrofia muscular (GRP). Os dois grupos foram submetidos aos mesmos testes hematológicos e bioquímicos, com a mesma frequência e durante o mesmo intervalo de tempo. Apesar de existir diferença estatisticamente significativa entre os grupos para alguns parâmetros hematológicos avaliados, todos os resultados obtidos estavam de acordo com os valores de referência utilizados. Na avaliação dos parâmetros bioquímicos séricos a dosagem de ALT no grupo GRNP ficou levemente acima da média, porém sem grandes significados clínicos A CK também apresentou níveis elevados no grupo GRP, devido à degeneração e necrose muscular característicos da doença, as alterações encontradas nessa análise já eram esperadas. Os demais parâmetros não se alteraram.The purpose of this study was to evaluate whether there are alterations in hematological and biochemical patterns of female Golden Retriever dogs carrying the gene for progressive muscular dystrophy compared to not carriers dogs of the same breed, age and gender. We analyzed 33 animals, divided into two groups; one consisting of 13 not carriers dogs Golden Retrievers (GRNP) and the other composed of 14 dogs Golden Retrievers carrying the gene for muscular dystrophy (GRP). Animals of both groups underwent biochemical and hematological tests with the same frequency and at the same time interval. Although there is a statistically significant difference between groups for some hematological parameters evaluated, all results were in line with the benchmarks used. In the assessment of serum biochemical parameters in the determination of ALT GRS group was slightly above average, but without major clinical significance CK also showed high levels in GRP group, due to muscle degeneration and necrosis characteristic of the disease, the changes found in this analysis were already expected. The other parameters did not change

Integrated didactics: an example of a curriculum model enhancing knowledge crossing

In this paper, we introduce an innovative course in the Portuguese Context, the Master's Course in “Integrated Didactics in Mother Tongue, Maths, Natural and Social Sciences”, taking place at the Lisbon School of Education and discussing in particular the results of the evaluation made by the students who attended the Curricular Unit - Integrated Didactics (CU-ID). This course was designed for in-service teachers of the first six years of schooling and intends to improve connections between different curriculum areas. In this paper, we start to present a few general ideas about curriculum development; to discuss the concept of integration; to present the principles and objectives of the course created as well as its structure; to describe the methodology used in the evaluation process of the above mentioned CU-ID. The results allow us to state that the students recognized, as positive features of the CU-ID, the presence in all sessions of two teachers simultaneously from different scientific areas, as well as invitations issued to specialists on the subject of integration and to other teachers that already promote forms of integration in schools. As negative features, students noted a lack of integrated purpose, applying simultaneously the four scientific areas of the course, and also indicated the need to be familiar with more models of integrated education. Consequently, the suggestions for improvement derived from these negative features. The students also considered that their evaluation process was correct, due to the fact that it was focused on the design of an integrated project for one of the school years already mentioned

Spermatogenesis in goats with and without scrotum bipartition

The objective of the present research was to quantify the seminiferous epithelium cells, spermatogenesis efficiency and characterize the ultrastrucure of Sertoli cells in goats. Eighteen goats were used and divided into three groups: Group I - goats without bipartition of the scrotum; Group II - animals with bipartition of the scrotum in up to 50% of the testicular length; Group III - goats with bipartition of the scrotum in more than 50% of the testicular length. The goat testes in Group III had a greater number of primary spermatocytes (25.37 +/- 4.55 cells per cross sections), spermatids (112 +/- 15.12 cells per cross sections), and Sertoli cells (9.46 +/- 1.74 cells per cross sections) than the animals in Groups land (P <0.05). The spermatogenic mitotic, meiotic, and general efficiency were greater in animals in Group III (1.25 +/- 0.28; 5.12 +/- 1.63; 6.44 +/- 1.96) when compared to those in Groups I and II. Sheet-like processes originated from the Sertoli cell body as simple and smooth structures which involved almost all the surface of germ cells. Slender cord-like processes originated from Sertoli cells and also from the sheet-like processes. The relative frequency of the cycle stages showed differences among the groups of goats studied, and the highest frequency was in Stage 3 (20.68% for goats in Group I, 21.15% for those in Group II, and 16.89% for the animals in Group III). In conclusion, goats with bipartition of the scrotum have a greater number of germ and Sertoli cells per cross section of seminiferous tubule, that indicated a greater sperm production when compared to the other groups, and the ultrastructure of the Sertoli cell process did not present any relationship with bipartition of the scrotum. (C) 2012 Elsevier B.V. All rights reserved.CNPq 620240/2006-

Estudo do complexo valvar atrioventricular cardíaco esquerdo em búfalos (Bubalus bubalis) da raça Jafarabadi

Atrioventricular valve complex of 30 Jafarabadi water buffaloes, adult males were studied in this research with no heart diseases. The animals were obtained from a slaughterhouse in Brazilian State of Parana. The hearts were opened at the third portion affording access to the valve complex. The complexes had its area, number and type of tendinous cords submitted to analysis. The results showed that the complex is composed by two cusps and four accessory cusps, two or three papillary muscles in which 10-25 tendinous cords fix on the cusps that face the ventricle wall. The total area of the complex was on average 38.56cm², with a minimum of 24.96cm² and a maximum of 55.54cm². Statistically, no relation between the number of cords and the cusps' area where they are inserted or with the number of papillary muscle where they originated from was observed.Foram estudados os complexos valvares atrioventricular esquerdo de 30 búfalos da raça Jafarabadi, machos e adultos, sem alterações cardíacas, provenientes de abatedouros do Estado do Paraná. Os corações foram examinados em seu terço médio para acesso ao complexo valvar, que foi submetido a estudos de área, número e tipificação de cordas tendíneas. Os resultados demonstram que este complexo é formado por duas cúspides principais e quatro cúspides acessórias, apresentam em sua formação de 2-3 músculos papilares, nos quais se inserem de 10-25 cordas tendíneas, que se fixam em cúspides voltadas para a parede do ventrículo. A área total deste complexo apresenta uma média de 38,56cm² com um mínimo de 24,96cm² e um máximo de 55,54cm². Estatisticamente não há relação entre número de cordas e a área da cúspide onde estas estão inseridas, nem com o número de músculos papilares dos quais elas provem