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1.
Acyclic mares (free of uterine infection and with typical acyclic endometria on biopsy) received daily intramuscular injections in oil of either 1.5 mg estradiol benzoate (n - 4) or progesterone (n = 5). Estradiol and progesterone treatment induced biopsy changes consistent with estrus or diestrus respectively (Kenney, 1978). Subsequently, seven mares with typical acyclic endometria were given ten daily intra-uterine infusions of from 400 to 10 000 pg estradiol-17β. All mares developed Streptococcus zooepidemicus infections which masked any endometrial changes which might have been induced by estradiol infusion.  相似文献   

2.
Knowledge about the reproduction of the endangered pygmy hippopotamus is almost non-existent. This study takes the first step toward changing this by devising a protocol for the collection, evaluation, and short-term preservation of semen of this endangered species. Semen was collected successfully from seven bulls by electroejaculation, using a specially designed rectal probe. Mean ± SEM values of native sperm parameters from combined best fractions were: motility—80.0 ± 4.1%, concentration—2421 ± 1530 × 106 cells/mL, total collected cell number—759 ± 261 × 106 cells, intact acrosome—87.8 ± 1.2%, intact morphology—52.7 ± 4.3%, and, for some, hypoosmotic swelling test—79.3 ± 4.4% and seminal plasma osmolarity—297.5 ± 3.3 mOsm. Seven different extenders were tested for sperm storage under chilling conditions: Berliner Cryomedium (BC), Biladyl®, modification of Kenney modified Tyrode’s medium (KMT), MES medium, Androhep®, boar M III extender and Human Sperm Refrigeration Medium. While differences between males were apparent, the BC was consistently superior to all other extenders in sperm motility and facilitated storage for 7 d with up to 30% motility and some motility even after 3 weeks. With this knowledge in hand, the obvious two directions for future research are to conduct artificial insemination and to develop a technique for sperm cryopreservation.  相似文献   

3.
Schlafer DH 《Theriogenology》2007,68(3):413-422
During the 1960s and 1970s, the clinical value of equine endometrial histopathology was firmly established after it was shown that fertility outcome was correlated with the presence and severity of specific microscopic lesions. The objective of this paper is to summarize reports from the veterinary literature published after the mid 1980s that describe new diagnostic methods of assessing equine uterine health using material collected by endometrial biopsy.  相似文献   

4.
5.
Optimization of equine sperm cryopreservation protocols requires an understanding of the water permeability characteristics and volumetric shrinkage response during freezing. A cell-shape-independent differential scanning calorimeter (DSC) technique was used to measure the volumetric shrinkage during freezing of equine sperm suspensions at cooling rates of 5 degrees C/min and 20 degrees C/min in the presence and absence of cryoprotective agents (CPAs), i.e., in the Kenney extender and in the lactose-EDTA extender, respectively. The equine sperm was modeled as a cylinder of length 36.5 microm and a radius of 0.66 microm with an osmotically inactive cell volume (V(b)) of 0.6V(o), where V(o) is the isotonic cell volume. Sperm samples were collected using water-insoluble Vaseline in the artificial vagina and slow cooled at < or = 0.3 degrees C/min in an Equitainer-I from 37 degrees C to 4 degrees C. By fitting a model of water transport to the experimentally obtained DSC volumetric shrinkage data, the best-fit membrane permeability parameters (L(pg) and E(Lp)) were determined. The combined best-fit parameters of water transport (at both 5 degrees C/min and 20 degrees C/min) in Kenney extender (absence of CPAs) are L(pg) = 0.02 microm min(-1) atm(-1) and E(Lp) = 32.7 kcal/mol with a goodness-of-fit parameter R(2) = 0.96, and the best-fit parameters in the lactose-EDTA extender (the CPA medium) are L(pg)[cpa] = 0.008 microm min(-1) atm(-1) and E(Lp)[cpa] = 12.1 kcal/mol with R(2) = 0.97. These parameters suggest that the optimal cooling rate for equine sperm is approximately 29 degrees C/min and is approximately 60 degrees C/min in the Kenney extender and in the lactose-EDTA extender. These rates are predicted assuming no intracellular ice formation occurs and that the approximately 5% of initial osmotically active water volume trapped inside the cells at -30 degrees C will form innocuous ice on further cooling. Numerical simulations also showed that in the lactose-EDTA extender, equine sperm trap approximately 3.4% and approximately 7.1% of the intracellular water when cooled at 20 degrees C/min and 100 degrees C/min, respectively. As an independent test of this prediction, the percentage of viable equine sperm was obtained after freezing at 6 different cooling rates (2 degrees C/min, 20 degrees C/min, 50 degrees C/min, 70 degrees C/min, 130 degrees C/min, and 200 degrees C/min) to -80 degrees C in the CPA medium. Sperm viability was essentially constant between 20 degrees C/min and 130 degrees C/min.  相似文献   

6.
In the accompanying article contributed by Robert B. Lawson, proposals are made for revising the curriculum for doctoral students in biology in order to enhance a transdisciplinary awareness of biological science. The article is written mainly in the context of Dr Lawson's role as a scientist and educator in the United States. BioEssays will welcome articles along similar lines from educators in other countries. These should be sent to the Staff Editor, Dr Adam S. Wilkins.  相似文献   

7.
Gilbert RO 《Theriogenology》1989,32(3):451-454
Luteolysis with subsequent shortening of diestrus has been reported to follow equine endometrial biopsy performed early in the luteal phase of the estrous cycle, but a comprehensive study of the effect of endometrial biopsy on cycle length at different times of the cycle has not been reported. In this study, endometrial biopsies were obtained from four different pony mares on each of Days 0, 4, 8, 12, 16 and 20 after ovulation as determined by serial palpation per rectum. Compared with control cycles in the same mares, the ovulatory interval was shortened in mares from which biopsies were obtained on Days 4 and 8, it was lengthened in from which samples were taken on Days 16 and 20 and it remained unchanged by biopsies performed on Days 0 and 12. Although the changes were less consistent and smaller than those observed in cows, our findings are similar to those reported for effects of endometrial manipulation or uterine infusion on the estrous cycle of cows.  相似文献   

8.
With the passing of Dr. Robert Bittman from pancreatic cancer on the 1st October 2014, the lipid research field lost one of the most influential and significant personalities. Robert Bittman's genius was in chemical design and his contribution to the lipid research field was truly immense. The reagents and chemicals he designed and synthesised allowed interrogation of the role of lipids in constituting complex biophysical membranes, sterol transfer and in cellular communication networks. Here we provide a review of these works which serve as a lasting memory to his life.  相似文献   

9.
10.
Knowledge concerning reproduction in common hippopotamus is scarce and in particular very little is known about male reproductive physiology and sperm cryopreservation. Testes were obtained from nine castrated bulls and sperm extracted from the epididymides of eight of these individuals. Mean ± SEM values of reproductive parameters were: testicular weight (including epididymis and tunicas)—275.9 ± 54.1 g, total sperm motility—88.1 ± 4.2%, total cells extracted—11.0 ± 3.6 × 109, intact acrosome—87.7 ± 1.8%, intact sperm morphology—51.6 ± 4.1%, and, for 3 individuals, hypoosmotic swelling test for membrane integrity—83.3 ± 1.8%. Chilled storage extenders tested were Berliner Cryomedium (BC), Biladyl®, modification of Kenney modified Tyrode's medium (KMT), and Human Sperm Refrigeration Medium (HSRM). Extender had significant effect on post-dilution motility and motility and intact morphology after 4h and 24h at 4°C (P ≤ 0.007 for all). Berliner Cryomedium and HSRM were superior to Biladyl® and KMT. Freezing extenders tested were BC with either 6% dimethyl sulfoxide (Me2SO), or 5%, 7%, or 10% glycerol. Post-thaw motility was < 5% in 3/7 bulls in all extenders. When frozen in BC with 6% Me2SO, one bull had 15% post-thaw motility and 3/7 had 20 to 60%. In glycerol, 3/7 had 15-30% post-thaw motility in 5%, 2/7 in 7%, and 1/7 in 10%. The extender had significant effect on post-chilling motility (P = 0.008), post-thaw morphology (P = 0.016), and motility 30 min after thawing (P = 0.015). Berliner Cryomedium with 6% Me2SO or 7% glycerol were the freezing extenders of choice. Information obtained in this study allows initiation of cryobanking of sperm from the common hippopotamus which is of particular importance for genetically valuable individuals.  相似文献   

11.
Previous studies have shown that the equine uterus produces many progesterone-dependent proteins throughout gestation. In particular, uterocalin and uteroferrin are detectable using electrophoresis or blot analyses but information regarding the immunohistochemical placental distribution of these two proteins is rare and information regarding uteroglobin is still lacking. The aim of the present study was to co-immunolocalise these three secretory proteins in the mare's uterus throughout gestation in an effort to understand their functional role in the maintenance of pregnancy. Therefore, endometrial biopsy samples were obtained from 20 pregnant mares between 16 and 309 days of gestation and labelled immunohistochemically for uteroglobin, uteroferrin and uterocalin. Uteroferrin remained detectable in almost every endometrial gland at all stages but with an increase in staining intensity as gestation advanced. The most progesterone-dependent protein, uterocalin, showed variable staining throughout gestation with the most intense labelling in early pregnancy and during the period of endometrial cup reaction. Uteroglobin secretion was only detectable in traces and only in individual glands throughout gestation. The results indicate that uterocalin and uteroferrin, but not uteroglobin, may play important roles in supplying nutrients for the conceptus, thereby contributing to the maintenance of pregnancy. However, further investigations are necessary to understand the role of uteroglobin during gestation.  相似文献   

12.
The review article presents some of the history of how paleoparasitology started in Brazil, making highlight the great responsible Dr. Luiz Fernando Ferreira and Dr. Adauto Araújo, the trajectory of paleoparasitology in Brazil since 1978 and its performance in science to the present day. In sequence, it is made a presentation of parasitological findings on human remains found in archaeological sites in South America, highlighting Brazil, Argentina, Chile, and Peru, where major discoveries have occurred. Many of the parasites found in archaeological material and mentioned in this review went out of Africa with the peopling of Europe and from there they dispersed around the world, where climatic conditions allow the transmission. However, humans have acquired other parasites of animals, since humans invaded new habitats or creating new habits adopting new technologies, thus expanding its range of influence on the environment. Thus, this review article is finalized with information that explain the importance of these findings in the interaction between parasites, human host, and ambient.  相似文献   

13.
The objectives of this paper are to review the chemical and biological properties of equine chorionic gonadotropin (eCG, PMSG) isolated from the serum. Comparisons are made with eCG isolated from endometrial cups, trophoblast cell culture medium, and low titer serum. The results show that eCG can vary, depending on the source, in both chemical and biological (LH and FSH activity) properties.  相似文献   

14.
Populations of Microtus montanus, the montane vole, have been extensively studied. It is known that their reproductive activity is closely linked to the availability of the chemicals in growing plants. We use a mathematical model here to study how the length of the vegetative season and the natural reproduction rhythm of voles are involved in the long term dynamics of the population numbers. In particular, we use data obtained from Timpie Springs, Utah, and from Jackson Hole, Wyoming, to formulate a model. The novelty of this model is its use of littering curves that highlight the temporally discrete nature of vole reproduction. The model shows how the timing of the vegetative season can influence vole population sizes.This work was supported in part by NSF Grant No. MCS-82-08986 and DMS85-14000 (FCH) and by the University of Utah where Dr. Murphy was a visitor  相似文献   

15.
This review is provided in recognition of the extensive contributions of Dr. Robert J. Lefkowitz to the G protein-coupled receptor (GPCR) field and to celebrate his 75th birthday. Since one of the authors trained with Bob in the 80s, we provide a history of work done in the Lefkowitz lab during the 80s that focused on dissecting the mechanisms that regulate GPCR signaling, with a particular emphasis on the GPCR kinases (GRKs). In addition, we highlight structure/function characteristics of GRK interaction with GPCRs as well as a review of two recent reports that provide a molecular model for GRK-GPCR interaction. Finally, we offer our perspective on some future studies that we believe will drive this field.  相似文献   

16.
Objective:  Office methods of endometrial sampling for outpatients with abnormal uterine bleeding should be minimally invasive. The purpose of this study was to determine the best method for detecting endometrial cancer in an outpatients setting.
Methods:  In all, 114 symptomatic women who were suspected of having endometrial disease by their local gynaecologist were enrolled in this study. After pelvic examination and transvaginal ultrasonography, endometrial cytology, suction endometrial curettage, and four-site endometrial biopsy were performed, in this order without anaesthesia in each patient. After endometrial sampling, the patient was asked to comment on the intensity of any pain experienced during each procedure. Then the final histological diagnosis made from the surgical materials was compared with the results of the three pre-operative methods.
Results:  Among the 114 consecutive patients, 56 had endometrial carcinoma, three had carcinosarcoma, six had endometrial hyperplasia, and 49 had benign conditions. The sensitivity of detecting malignancy was 88% (52/59) with endometrial cytology, 92% (54/59) with suction curettage, and 88% (52/59) with four-site biopsy. When endometrial cytology was combined with suction curettage, the sensitivity of detecting malignancy was increased from 92% to 98%, whereas the sensitivity was increased from 88% to 97%, when endometrial cytology was added to four-site biopsy. Suction curettage was significantly less painful than four-site biopsy.
Conclusion:  Our data indicated that suction curettage plus endometrial cytology was the best combination for pathological examination of outpatients with abnormal uterine bleeding.  相似文献   

17.
Maternal recognition of pregnancy is a physiological process that primarily describes endometrial responses to a conceptus. Recognition of a conceptus prevents the release of prostaglandin F, thereby ensuring survival of the corpus luteum and continued progesterone production. Exactly how this occurs in the mare is poorly understood. Because prostaglandin F is a pro‐inflammatory hormone, we hypothesized that differential gene expression in the endometrium at the time of maternal recognition reflects an anti‐inflammatory event leading to decreased prostaglandin F secretion. Mares were inseminated, and endometrial biopsies were recovered from pregnant mares on Day 18 post‐ovulation. In subsequent estrous cycles, mares were not inseminated and Day 18 post‐ovulation endometrial biopsies were collected (non‐pregnant control, matched per individual). Endometrial gene expression profiles were examined by screening an Affymetrix equine GeneChip containing probes specific for genes related to inflammatory processes. Microarray analysis revealed 118 genes that were up‐regulated and 93 genes that were down‐regulated (P < 0.001) at least 1.5‐fold in the endometrium of pregnant versus non‐pregnant mares. Quantitative, real‐time RT‐PCR confirmed the microarray results for three up‐regulated genes homologous to TSC22D3, PPAPDC2, and KLF6, and three down‐regulated genes homologous to ESR1, MARCKSL1, and EPSTI1 (P < 0.05). It is concluded that the presence of the equine embryo induces differential gene expression in the endometrium of Day 18 pregnant mares, and that these genes are associated with inflammatory processes and pathways involving cellular growth and proliferation. The results from this study provide important new insights into endometrial gene expression in response to early equine pregnancy. Mol. Reprod. Dev. 79: 777–784, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

18.
In Memory     
Abstract

Dr. Mathias P. Mertes, well-known medicinal chemist, member of the Editorial Advisory Board of Nucleosides & Nucleotides, and a good friend, died unexpectedly earlier this year. An obituary written by Drs. Gary Grunewald and Robert Hanzlik of the University of Kansas is presented below followed by a list of the publications of Dr. Mertes. Many of us have pleasant memories of stimulating interactions with Matt. We can hope that the spirit and enthusiasm with which Matt approached science has rubbed off on some of us. He will be missed.  相似文献   

19.
20.
The equine embryo must signal its presence to the uterus for pregnancy to continue to term. Mobility of the conceptus throughout the uterus is crucial for its survival, and this action presumably permits the conceptus to transmit its antiluteolytic signal to the endometrium. Studies were completed to establish whether this unidentified antiluteolytic signal targets prostaglandin G/H synthase 2 (PGHS2), a rate limiting enzyme in converting arachidonic acid to prostaglandins (PGs). In the first study, quantitative RT-PCR was used to determine the relative abundance of PGHS2 mRNA in endometrium derived from estrous cyclic and pregnant mares on day 14 post-ovulation. PGHS2 mRNA abundance was substantially greater in endometrium from estrous cyclic mares. Additional studies were completed to better understand PGHS2 in equine endometrium. An estrogen and progesterone treatment regimen in ovariectomized mares was developed as a test model for detecting endometrial PGHS2 mRNA. Also, exposing endometrial explants to conceptus secretions (conditioned culture medium) decreased PGHS2 mRNA abundance whereas exposing explants to oxytocin increased PGHS2 mRNA abundance. Exposure to conceptus secretions also decreased PGF2α concentrations in explant-conditioned medium whereas oxytocin supplementation increased PGF2α concentrations in medium. These data support the hypothesis that PGHS2 is a target for the antiluteolytic signal produced by equine conceptuses during early pregnancy. Also, the endometrial explant culture system used for these studies can serve as a model for identifying and characterizing the maternal recognition of pregnancy factor in equids.  相似文献   

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