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981.
982.
983.
Olivier D'Amours zquiel Calvo Sylvie Bourassa Patrick Vincent Patrick Blondin Robert Sullivan 《Molecular reproduction and development》2019,86(8):999-1012
In the context of artificial insemination, male fertility is defined as the ability to produce functional spermatozoa able to withstand cryopreservation. We hypothesized that interindividual variations in fertility depend on the proportion of the fully functional sperm population contained in the insemination dose. The objective of this study was to identify protein markers of the fully functional sperm subpopulation. Insemination doses from four high‐fertility (HF) and four low‐fertility (LF) bulls with comparable post‐thaw quality parameters were selected for proteomic analysis using iTRAQ technology. Thawed semen was centrifuged through a Percoll gradient to segregate the motile (high density [HD]) from the immotile (low density [LD]) sperm populations. Sperm proteins were extracted with sodium deoxycholate and four groups were compared: LD and HD spermatozoa from LF and HF bulls. A total of 498 unique proteins were identified and quantified. Comparison of HD spermatozoa from HF and LF bulls revealed that five proteins were significantly more abundant in the HF group (AK8, TPI1, TSPAN8, OAT, and DBIL5) whereas five proteins were more abundant in the LF group (RGS22, ATP5J, CLU, LOC616319, and CCT5). Comparison of LD spermatozoa from HF and LF bulls revealed that four proteins were significantly more abundant in the HF group (IL4I1, CYLC2, OAT, and ARMC3) whereas 15 proteins were significantly more abundant in the LF group (HADHA, HSP90AA1, DNASE1L3, SLC25A20, GPX5, TCP1, HIP1, CLU, G5E622, LOC616319, HSPA2, NUP155, DPY19L2, SPERT, and SERPINE2). DBIL5, TSPAN8, and TPI1 showed potential as putative markers of the fully functional sperm subpopulation. 相似文献
984.
Diseased American eels, Anguilla rostrata , were collected from an eel culture facility in South Carolina and examined. The disease was characterized by skin lesions located on the body. A bacterium identified as Aeromonas salmonicida was isolated from the lesions and shown to be the causative agent. The bacterium was also isolated from the kidney during later stages of the disease. 相似文献
985.
Patrick Sullivan 《CMAJ》1990,143(5):404-405
986.
A comparison of two populations of decidual cells by immunocytochemistry and prostaglandin production 总被引:1,自引:0,他引:1
The decidua has been implicated in the control of human labour, particularly through changes in prostaglandin production, but this tissue contains a number of different cell types. A density gradient system was used to obtain two populations of cells from term human decidua, and these populations were characterised. The more dense cells (population B) was a mixed population, predominantly macrophages (80%), but small numbers of T- and B-lymphocytes were also present, as identified by immunocytochemistry. Most of these cell types also contained detectable levels of cyclooxygenase enzyme. The less-dense cell population (population A) did not contain significant numbers of the above cell types and released prolactin, suggesting that they were decidual stromal cells. This preparation of decidual stromal cells may be of use in defining the functions of these cells in labour. 相似文献
987.
An autoradiographic study of the distribution of fibers from the dorsal motor nucleus of the vagus to the digestive tube of the rat 总被引:1,自引:0,他引:1
At the present time, complete agreement on the origin and course of parasympathetic preganglionic fibers to the alimentary canal has not been reached. The purpose of this study was to trace vagal fibers to the abdominal cavity and to follow the distribution of these fibers to the digestive tube. The technique used was to label neurons in the dorsal motor nucleus of the vagus (DMX) with 3H-leucine and then to follow the orthograde transport. 16 albino rats were used in this experiment. The right DMX in one group of rats and the left DMX in the other group was injected with 25 microCi of 3H-leucine in three injections. The injection sites and tissue sections from various areas of the digestive tube were processed for autoradiography. A heavy label was observed in the injection site and it could be traced down the vagus nerve through the thorax into the abdomen. Labelled vagal fibers were found in the parasympathetic ganglia of the stomach, small intestine and colon. 相似文献
988.
The binding of cytochrome b5 to phosphatidylcholine vesicle 总被引:2,自引:0,他引:2
Cytochrome b5 was isolated from rabbit liver by a detergent procedure and by a proteolytic procedure. Only cytochrome b5 isolated by the detergent procedure would bind to phosphatidylcholine vesicles and the cytochrome b5 was not removed by 1 M KCl. The Eo′ and visible absorption spectrum of the cytochrome b5 and its rate of reduction by NADH plus NADH-cytochrome b5 reductase did not change appreciably upon binding. These data indicate that cytochrome b5 is bound to phospholipid by a hydrophobic interaction which leaves the heme portion in the aqueous environment. 相似文献
989.
Estradiol and progesterone regulation of immunoglobulin A and G and secretory component in cervicovaginal secretions of the rat 总被引:4,自引:0,他引:4
The present study examined the influence of hormones on the levels of immunoglobulins A (IgA) and G (IgG) and secretory component (SC) in cervicovaginal secretions of ovariectomized rats. Administration of estradiol to ovariectomized rats resulted in a significant decline in cervicovaginal content of IgA, IgG and SC. This response was dose dependent and was not prevented by administration of dexamethasone, a potent synthetic glucocorticoid, with estradiol. Treatment of ovariectomized rats with progesterone also lowered the levels of IgA and SC in cervicovaginal secretions. In contrast, dexamethasone had no apparent vaginal effect. The action of estradiol on cervicovaginal IgA, IgG and SC appears to be independent of uterine influence. This conclusion is based upon our observation that estrogen treatment of rats with ligations at their uterocervical junction still have decreased cervicovaginal IgA and SC levels. In parallel with this inhibitory effect, estradiol administration stimulated the accumulation of IgA and SC in uterine secretions. These findings indicate that the sex hormones play a role in regulating IgA, IgG and SC content in cervicovaginal secretions. In addition, it suggests that hormonal balance in females may influence the immune response of the reproductive tract to infectious disease. 相似文献
990.
James D. Sullivan 《CMAJ》1985,132(9):1004-1005