Immunohistochemical Localization of Oestrogen Receptors α and β, Progesterone Receptor and Aromatase in the Equine Placenta     

MMM Abd-Elnaeim  IR Derar  S Wilsher  WR Allen  R Leiser  G Schuler 《Reproduction in domestic animals》2009,44(2):312-319

The functions of placental oestrogens during equine pregnancy are still unclear. Yet, they may act predominantly as local regulators of growth and differentiation in the microplacentomes. Thus, expression patterns of oestrogen receptors (ERs) α and β were investigated in the microcotyledonary placenta from pregnant mares at 110, 121, 179, 199 and 309 days of gestation by immunohistochemistry. In microplacentomes, both the ER isoforms were detected in trophoblast (T) cells, chorionic villous stroma (FS), microcaruncular epithelium (ME) and microcaruncular stroma (MS). Proportions of positive cells were 38–91% (T), 11–41% (FS), 55–89% (ME), 17–51% (MS) for ERα and 66–76% (T), 21–37% (FS), 41–68% (ME) and 24–55% (MS) for ERβ. Between days 110 and 199, proportions of cells positive for progesterone receptor (PR) varied between 19% and 62% (T), 3% and 50% (CS), 15% and 46% (ME), and 4% and 33% (MS). At day 309, PR was virtually absent in T, CS and ME (percentages < 0.1), whereas in MS 14.3% of cells were still positive. The expression of ERs and PR in equine microplacentomes gives evidence for a role of placental steroids as regulators of placental growth, differentiation and function. The detection of ERα, ERβ and PR in foetal and maternal vascular tissue suggests that placental steroids are also involved in the control of placental angiogenesis and /or vascular functions. The co-localization of ERs with aromatase in T suggests auto- or intracrine functions of oestrogens in this cell type.  相似文献   

Expression of Fibroblast Growth Factors (FGF) and FGF Receptor (FGFR) in the Horse Placenta     

C. Pfarrer    M. Abd-Elnaeim  W. R. Allen    S. Wilsher    D. Schams    R. Leiser 《Anatomia, histologia, embryologia》2005,34(S1):39-40

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Gross and microscopic anatomy of the pineal gland in Nasua nasua--coati (Linnaeus, 1766)     

Favaron PO  Mançanares CA  De Carvalho AF  Ambrósio CE  Leiser R  Miglino MA 《Anatomia, histologia, embryologia》2008,37(6):464-468

Nasua nasua, coati, is a mammal of the Carnivora order and Procyonidae family. It lives in bands composed of females and young males. The pineal gland or epiphysis of brain is endocrine, producing the melatonin. Its function is the control of the cycle of light environment, characteristic of day and night. For this research, five adult coatis were used, originating from CECRIMPAS-UNIfeob (Proc. IBAMA 02027.003731/04-76), Brazil. The animals were killed and perfusion-fixed in 10% formaldehyde. Pineals were measured and a medium size was found to be 2.3-mm-long and 1.3-mm-wide. Pineal gland was located in the habenular commissure in the most caudal portion of the third ventricular roof, lying in a dorso-caudal position from the base to the apex. Pinealocytes were predominantly found in the glandular parenchyma. Distinct and heterogeneous arrangements of these cells throughout the three pineal portions were observed as follows: linear cords at the apex, circular cords at the base of the gland, whereas at the body a transition arrangement was found. Calcareous concretions could be observed in the apex. The pineal gland was classified as subcallosal type [Rec. Méd. Vét.1, 36 (1956)] and as AB type [Prog. Brain Res. 42, 25 (1979); The Pineal Organ, Berlin/Heidelberg: Springer-Verlag (1981)].  相似文献   

Light and scanning electron microscopic study on the blood vascular system of the donkey placenta     

Saber A  Abd-Elnaeim M  Hembes T  Pfarrer C  Salim A  Leiser R 《Anatomia, histologia, embryologia》2008,37(2):86-94

The donkey placenta is diffuse and epitheliochorial with numerous microplacentomes consisting of a fetal microcotyledonary and a maternal microcaruncular part. The microplacentomal vasculature during the last third of pregnancy has been investigated by light microscopy in comparison to scanning electron microscopy of the materno-fetal contact surface and corrosion casts of blood vessels after plastic instillation from either the microcotyledonary or the microcaruncular side, and, for the first time in a perissodactyle, from both sides. Morphological data were semiquantitatively evaluated. The supplying parts of both, the microcotyledonary and the microcaruncular vascular system are strictly proximo-distally oriented, thus reaching the capillary systems or working parts in the shortest way possible. The straight course of the vasculature, particularly on the fetal side, suggests the occurrence of venulo-arteriolar back diffusion. The fetal capillary system consists of convolutes confronting the maternal septal capillary complexes in a countercurrent way. This materno-fetal blood flow interrelationship is highly efficient in terms of placental exchange, which is further supported (1) by dilations and increasing coiling of the fetal venular capillary limbs in particular and (2) by a decrease in the interhaemal distance from 12.5 to 7.2 microm between the two capillary systems. Besides the countercurrent blood flow interrelationship, some maternal branch arterioles reach the septal capillary system from the maternally oriented pole of the microplacentome or microcaruncle, respectively, resulting in the less efficient crosscurrent blood flow. Hence, in the donkey placenta fetal and maternal blood vessels meet in a mix of countercurrent and crosscurrent flow patterns.  相似文献   

Grassland vegetation changes and nocturnal global warming   总被引：4，自引：0，他引：4  

RD Alward  JK Detling  DG Milchunas 《Science (New York, N.Y.)》1999,283(5399):229-231

Global minimum temperatures (TMIN) are increasing faster than maximum temperatures, but the ecological consequences of this are largely unexplored. Long-term data sets from the shortgrass steppe were used to identify correlations between TMIN and several vegetation variables. This ecosystem is potentially sensitive to increases in TMIN. Most notably, increased spring TMIN was correlated with decreased net primary production by the dominant C4 grass (Bouteloua gracilis) and with increased abundance and production by exotic and native C3 forbs. Reductions in B. gracilis may make this system more vulnerable to invasion by exotic species and less tolerant of drought and grazing.  相似文献   

Identification of seed protein and oil related QTL in 944 RILs from a diallel of early-maturing European soybean     

Xintian Zhu  Willmar L.Leiser  Volker Hahn  Tobias Würschum 《作物学报(英文版)》2021,(1):238-247

Soybean[Glycine max(L.)Merr.]is a global protein source and is currently expanding in Central and Northern Europe.Protein and oil content are two important quality traits that have been studied in different germplasm,however,their genetic architecture in earlymaturing European soybean has not been investigated yet.In this study,we therefore performed QTL mapping for both traits using 944 recombinant inbred lines derived from eight families from a half-diallel crossing design.We identified five QTL for each trait,with the QTL on chromosomes 8,15,and 20 being identified for both protein content and oil content.The known major QTL on chromosome 20 was detected in four families whereas the other QTL were only found in single families.Further analyses revealed the QTL to have pleiotropic but inverse effects on both traits.The effect of the major QTL was comparable between families,illustrating that it is largely independent from the genetic background.Collectively,our results illustrate the quantitative nature of protein and oil content in early European soybean.Marker-assisted selection for the QTL is possible,but the inverse effect on protein and oil content should be kept in mind.  相似文献   

Genome Multiplication in Trophoblast Giant Cells of Sheep, Goat, Water Buffalo and Deer: an Image Cytophotometric Study     

K Klisch  G Schuler  MA Miglino  R Leiser 《Reproduction in domestic animals》2000,35(3-4):145-148

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Radar detection of the nucleus and coma of comet hyakutake     

JK Harmon  SJ Ostro  LAM Benner  KD Rosema  RF Jurgens  R Winkler  DK Yeomans  D Choate  R Cormier  JD Giorgini  DL Mitchell  PW Chodas  R Rose  D Kelley  MA Slade  ML Thomas 《Science (New York, N.Y.)》1997,278(5345):1921-1924

Radar observations of comet Hyakutake (C/1996 B2) made at the Goldstone Deep Space Communications Complex in California have detected echoes from the nucleus and from large grains in the inner coma. The nucleus of this bright comet was estimated to be only 2 to 3 kilometers in diameter. Models of the coma echo indicate backscatter from porous, centimeter-size grains ejected anisotropically at velocities of tens of meters per second. The radar observations suggest that a comet's activity may be a poor indicator of its size and provide evidence that large grains constitute an important component of the mass loss from a typical active comet.  相似文献   

Reasons for liking and choosing a cat as a pet     

AL PODBERSCEK  JK BLACKSHAW 《Australian veterinary journal》1988,65(10):332-333

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Analytical Diagnostic Peritoneal Lavage in the Diagnosis of Intra-abdominal Injury     

Thompson DC  Pearce WJ  Longerbeam JK 《Veterinary surgery : VS》1985,14(4):327-327

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