Reproduction in natural populations of the Australian ringtail possum, Pseudocheirus peregrinus (Marsupialia: Phalangeridae) in Victora.

Reproductive data from 83 female and 34 male ringtail possums, living in natural populations, have been accumulated over a 3-yr period (March 1960-May 1963). Reproductive tracts from 75 females killed during this period have been examined. Pseudocheirus is polyoestrous and breeds between the latter half of April and the end of November. The whole female reproductive tract and, in the male, the testes then undergo involution until the next breeding season. The majority of conceptions occur early in the breeding season when one to three eggs are shed and fertilized at one time. Supra-ovulation was not observed and the reproductive wastage was very low during pouch life. The mean litter size was two. It is exceptional for females to conceive a second time in one breeding season. Of the four teats, the posterior pair were selected by 85 % of the new-born young. The frequency of lactation in each posterior teat was approximately equal in 58 females. In advanced pregnancy (foetal head length, 6.5 mm) the subepithelial blood net of the uterine mucosa was more highly developed adjacent to a dorsal and ventral area of the vascular portion of the foetal yolksac. In these regions dense foetal blood vessel nets were formed by intense localized branching of the foetal vitelline veins on the yolksac. The foetal membrane, the allantois, was surprisingly large (8 mm diam.), and although not attached to the chorion possessed a conspicuous blood net in its base. An account of the histology of the ovary and reproductive tract includes the following reproductive conditions : juvenile, oestrus, early and late pregnancy, lactation, and anoestrus. Reproduction in Pseudocheirus is briefly compared to that of other marsupial species.

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Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080766 ◽

1977 ◽

Vol 35 ◽

pp. 668-669

Author(s):

Mai M. Said ◽

Ramesh K. Nayak ◽

Randall E. McCoy

Keyword(s):

Guinea Pig ◽

Reproductive Tract ◽

Three Dimensional ◽

Female Reproductive Tract ◽

Human Female ◽

Surface Ultrastructure ◽

Transmission Electron ◽

Sem Study ◽

Uterine Mucosa ◽

Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

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The Female Reproductive-Tract of the Australian Sea Lion, Neophoca-Cinerea (Peron, 1816) (Carnivora, Otariidae)

Australian Journal of Zoology ◽

10.1071/zo9910351 ◽

1991 ◽

Vol 39 (3) ◽

pp. 351 ◽

Cited By ~ 7

Author(s):

RA Tedman

Keyword(s):

Reproductive Tract ◽

Female Reproductive Tract ◽

Breeding Cycle ◽

Embryonic Diapause ◽

Sea Lion ◽

Neophoca Cinerea ◽

Australian Sea Lion ◽

Uterine Mucosa ◽

Breeding Seasons ◽

Uterine Glands

This first account of the morphology of the female reproductive tract of the Australian sea lion, Neophoca cinerea, is based on examination of 15 specimens. The morphology of the female reproductive tract is similar in most respects to that in other pinniped species; only features peculiar to the species are described. The Y-shaped, bicornuate uterus is for the most part septate, but has a common uterine canal that is relatively much longer than that in other otariids. The uterine mucosa of newborns is slightly hypertrophied and regresses considerably by 3 weeks postpartum. During the embryonic diapause the uterine mucosa has serrated luminal epithelium, coiled uterine glands, and tall luminal and glandular epithelia. The mucosa of the adult vagina decreases in thickness from 100-mu-m at about 2 weeks postpartum to 20-mu-m 14.5 weeks postpartum, indicative of the regressive phase typical of the delay period in other pinnipeds. The urethral meatus lacks urinary papillae, unlike most other pinnipeds. A relatively large clitoris is present, and an os clitoridis was collected from one old individual. A monoestrous cycle seemed to occur in four animals, but a polyoestrous cycle is suspected in at least one individual. Ovulation occurs from alternate ovaries in successive pregnancies. Corpora albicantia are retained for at least three breeding seasons and probably longer. Implantation occurs in the midsection of the uterine cornu, ipsilateral to the ovary that released the egg. The maximum period of embryonic diapause cannot be ascertained from the available data, although a delay of about 8-9 months is possible if the breeding cycle (pregnancy cycle) lasts about 18 months.

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Transcriptome and proteome dynamics of cervical remodeling in the mouse during pregnancy

Biology of Reproduction ◽

10.1093/biolre/ioab144 ◽

2021 ◽

Author(s):

Shanmugasundaram Nallasamy ◽

Hector H Palacios ◽

Rohit Setlem ◽

Mariano Colon Caraballo ◽

Kelvin Li ◽

...

Keyword(s):

Reproductive Tract ◽

Isotope Labeling ◽

Late Pregnancy ◽

Female Reproductive Tract ◽

High Turnover ◽

Structural Reorganization ◽

Fibrillar Collagens ◽

Tissue Compliance ◽

Cervical Remodeling ◽

Rapid Transition

Abstract During gestation, the female reproductive tract must maintain pregnancy while concurrently preparing for parturition. Here, we explore the transitions in gene expression and protein turnover (fractional synthesis rates [FSR]) by which the cervix implements a transition from rigid to compliant. Shifts in gene transcription to achieve immune tolerance and alter epithelial cell programs begin in early pregnancy. Subsequently, in mid-to-late pregnancy transcriptional programs emerge that promote structural reorganization of the extracellular matrix (ECM). Stable isotope labeling revealed a striking slowdown of overall FSRs across the proteome on gestation day 6 that reverses in mid-to-late pregnancy. An exception was soluble fibrillar collagens and proteins of collagen assembly, which exhibit high turnover in non-pregnant cervix compared to other tissues and FSRs that continue throughout pregnancy. This finding provides a mechanism to explain how cross-linked collagen is replaced by newly synthesized, less-cross-linked collagens, which allows increased tissue compliance during parturition. The rapid transition requires a reservoir of newly synthesized, less cross-linked collagens, which is assured by the high FSR of soluble collagens in the cervix. These findings suggest a previously unrecognized form of “metabolic flexibility” for ECM in the cervix that underlies rapid transformation in compliance to allow parturition.

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Histology of Reproduction and the Estrus Cycle in the Female Fur Seal, Callorhinus ursinus

Journal of the Fisheries Research Board of Canada ◽

10.1139/f64-070 ◽

1964 ◽

Vol 21 (4) ◽

pp. 773-811 ◽

Cited By ~ 36

Author(s):

A. M. Craig

Keyword(s):

Corpus Luteum ◽

Breeding Season ◽

Reproductive Tract ◽

Follicular Development ◽

Estrus Cycle ◽

Gradual Process ◽

Uterine Mucosa ◽

Causative Agents ◽

Nulliparous Female ◽

First Time

Gross and histological analyses of the reproductive tracts from 72 multiparous females, 12 nulliparous females, and 28 non-pregnant females, taken pelagically in the eastern Pacific and on the Pribilof Islands between 1959 and 1961, have been used to determine the histology and physiology of the estrus cycle, the age of sexual maturity, and certain causes of prenatal mortality.The ovaries alternate in function, one ovary ovulating in one breeding season, the opposite ovary ovulating in the next. An undetermined factor suppresses follicular development in the ovary containing a corpus luteum of pregnancy; suppression maintains for 6 months after parturition. Graafian follicular development is greatest in June, with an average of 15 follicles in the ovary destined to ovulate. About four of these will enlarge abruptly in July; one will reach ovulation size (10 mm or greater in diameter) and rupture; the rest will become atretic.Ovulation occurs spontaneously 3–5 days after parturition in mid July. If fertilization is accomplished, the resulting blastocyst remains free in the uterus until early or mid November, when it implants in the mucosa.The newly formed corpus luteum is actively secretory for a month after ovulation. During this time, follicular development is suppressed in both ovaries, and the uterine mucosa prepares for implantation. From the middle of August, the corpus luteum regresses; the luteal cells are vacuolated, and secretion is minimal. This is reflected in a recrudescence of follicular activity in the ovary containing the corpus luteum, and regression of the associated uterine mucosa. Immediately prior to implantation the corpus luteum resumes secretion, and the mucosa is prepared for implantation. Placentation is established during December. Luteal degeneration begins in January and is progressive until parturition, when the corpus luteum appears to be non-secretory. Luteal degeneration has no effect on the pregnant uterine horn; it is assumed that the placenta secretes hormones sufficient to replace the luteal hormones.A nulliparous female ovulates for the first time in late August or September, [Formula: see text] months later than subsequent ovulations. On the basis of gross reproductive examination, approximately 70% of females ovulate for the first time at 4 years of age. Since the pregnancy rate of 5-year-olds is consistently about 50%, probably a number of 4-year-olds do not mate, either because ovulation occurs after the breeding season, or because breeding males are not available.Prenatal mortalities take 3 forms: "missed" pregnancies, abortions, and resorptions. On the basis of histological examinations, "missed" pregnancies are ultimately due to failure of implantation. Three conditions are responsible: failure of fertilization, failure of implantation, or malfunction of the reproductive tract which precludes pregnancy. Abortion results in the expulsion of a conceptus from the uterus before term; resorption is a gradual process of dissolution of the conceptus within the uterus. On the basis of histological evidence, three causative agents of abortion and resorption are apparent: degeneration of the corpus luteum after implantation, malfunction of the uterine mucosa, and inter-uterine mortality of the conceptus.

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Distinct Characteristics of Endometrial and Decidual Macrophages and Regulation of Their Permissivity to HIV-1 Infection by SAMHD1

Journal of Virology ◽

10.1128/jvi.01730-14 ◽

2014 ◽

Vol 89 (2) ◽

pp. 1329-1339 ◽

Cited By ~ 19

Author(s):

Héloïse Quillay ◽

Hicham El Costa ◽

Romain Marlin ◽

Marion Duriez ◽

Claude Cannou ◽

...

Keyword(s):

Reproductive Tract ◽

Female Reproductive Tract ◽

The Body ◽

Target Cells ◽

Mucosal Protection ◽

Protective Mechanisms ◽

Mucosal Transmission ◽

Uterine Mucosa ◽

Hiv 1

ABSTRACTIn order to develop strategies to prevent HIV-1 (human immunodeficiency virus type 1) transmission, it is crucial to better characterize HIV-1 target cells in the female reproductive tract (FRT) mucosae and to identify effective innate responses. Control of HIV-1 infection in the decidua (the uterine mucosa during pregnancy) can serve as a model to study natural mucosal protection. Macrophages are the main HIV-1 target cells in the decidua. Here we report thatin vitro, macrophages and T cells are the main HIV-1 targets in the endometrium in nonpregnant women. As reported for decidual macrophages (dM), endometrial macrophages (eM) were found to have an M2-like phenotype (CD68+CD163+CD206+IL-10high). However, eM and dM may belong to different subpopulations, as they differently express certain markers and secrete different amounts of proinflammatory and anti-inflammatory cytokines. We observed strong expression of the SAMHD1 restriction factor and weak expression of its inactive form (pSAMHD1, phosphorylated at residue Thr592) in both eM and dM. Infection of macrophages from both tissues was enhanced in the presence of the viral protein Vpx, suggesting a role for SAMHD1 in the restriction of HIV-1 infection. This study and further comparisons of the decidua with FRT mucosae in nonpregnant women should help to identify mechanisms of mucosal protection against HIV-1 infection.IMPORTANCEThe female reproductive tract mucosae are major portals of HIV-1 entry into the body. The decidua (uterine mucosa during pregnancy) can serve as a model for studying natural mucosal protection against HIV-1 transmission. A comparison of target cells and innate responses in the decidua versus the endometrium in nonpregnant women could help to identify protective mechanisms. Here, we report for the first time that macrophages are one of the main HIV-1 target cells in the endometrium and that infection of macrophages from both the endometrium and the decidua is restricted by SAMHD1. These findings might have implications for the development of vaccines to prevent HIV-1 mucosal transmission.

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Surface ultrastructure of danazol treated rat endometrium: A SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007641x ◽

1983 ◽

Vol 41 ◽

pp. 556-557

Author(s):

R.P. Apkarian ◽

J.S. Sanfilippo

Keyword(s):

Cross Sections ◽

Reproductive Tract ◽

Preliminary Investigation ◽

Breast Disease ◽

Distal Segment ◽

Uterine Horn ◽

Female Reproductive Tract ◽

Ultrastructural Changes ◽

Cycle Phase ◽

Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

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The application of electron microscopy to diagnosis in gynecologic neoplasms and tumor-like conditions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110787 ◽

1984 ◽

Vol 42 ◽

pp. 102-105

Author(s):

Lawrence M. Roth

Keyword(s):

Electron Microscopy ◽

Reproductive Tract ◽

Malignant Tumors ◽

Frozen Section ◽

Cost Effective ◽

Female Reproductive Tract ◽

Ultrastructural Examination ◽

Specific Diagnosis ◽

Potential Value ◽

Gynecologic Neoplasms

The female reproductive tract may be the site of a wide variety of benign and malignant tumors, as well as non-neoplastic tumor-like conditions, most of which can be diagnosed by light microscopic examination including special stains and more recently immunoperoxidase techniques. Nevertheless there are situations where ultrastructural examination can contribute substantially to an accurate and specific diagnosis. It is my opinion that electron microscopy can be of greatest benefit and is most cost effective when applied in conjunction with other methodologies. Thus, I have developed an approach which has proved useful for me and may have benefit for others. In cases where it is deemed of potential value, glutaraldehyde-fixed material is obtained at the time of frozen section or otherwise at operation. Coordination with the gynecologic oncologist is required in the latter situation. This material is processed and blocked and is available if a future need arises.

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