Ultrastructural aspects of the oesophageal and reproductive systems of the equine parasiteStrongylus vulgaris

AbstractThe ultrastructure of the dorsal oesophageal gland ampulla and its relationship with the oesophagus, oesophageal ultrastructure, and control mechanisms in oesophageal activity were studied. Terminal ducts of the sub-ventral glands open through the oesophageal crown at the base of the buccal cavity. The terminal duct of the dorsal oesophageal gland running through the dorsal gutter opens to the exterior at the rim ‘groove’ of the buccal capsule. The posterior oesophageal region is clavate and the cuticle of the lumen folds to form outlet valves, ‘valvulae’. An inconspicuous oesophago-intestinal valve (three lobes) connects oesophagus and intestine and is visualized in the open and shut position. In the female reproductive tract, with the exception of the uterus, the cells lie on a thick, irregular (convoluted) basal lamina. The apical plasma membrane of the uterus, and seminal receptacle, extend into the lumen by microvilli-like projections with which spermatozoa make intimate contact. The lumen of the uterus is filled with oocytes, fertilized and unfertilized. Testicular cells have two parts linked by a rachis. Spermatocytes are elongated with a large nucleus, distinct nuclear membrane, and many granules. The apical membrane of the rachis forms long microvilli-like projections with balloon-like tips. The amoeboid spermatozoa contain membrane specializations, a nucleus devoid of a membrane, and are enclosed by a pseudopodial-like extension.

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Effects of GnRH, PGF2α and oxytocin treatments on conception rate at the time of artificial insemination in lactating dairy cows

Czech Journal of Animal Science ◽

10.17221/1283-cjas ◽

2011 ◽

Vol 56 (No. 6) ◽

pp. 279-283 ◽

Cited By ~ 1

Author(s):

A. Gümen ◽

A. Keskin ◽

G. Yilmazbas-Mecitoglu ◽

E. Karakaya ◽

S. Cevik ◽

...

Keyword(s):

Dairy Cows ◽

Artificial Insemination ◽

Reproductive Tract ◽

Female Reproductive Tract ◽

Conception Rate ◽

Beneficial Effects ◽

Lactating Dairy Cows ◽

Conception Rates ◽

Prostaglandin F ◽

And Control

In several studies, hormones such as gonadotropin-releasing hormone (GnRH), prostaglandins and oxytocin were used to increase pregnancy rate by inducing ovulation and improving the sperm transport in the female reproductive tract in lactating dairy cattle. The objective of this study was to compare the effects of GnRH, prostaglandin F2α (PGF2α) and oxytocin treatments at the time of artificial insemination (AI) after spontaneous oestrus on the conception rate (CR) of lactating dairy cows. Oestrus was detected by visual observations by experienced personnel. All cows (n = 430, 308 Holstein-Frisian and 122 Swedish-Red dairy cows) were inseminated based on the am/pm rule by veterinarians of the farm. After AI, cows were alternately assigned to one of the four treatment groups: (1) GnRH (n = 113); (2) PGF2α (n = 106); (3) oxytocin (n = 106) and (4) non-treated control (n = 105). Pregnancy diagnosis was performed 28–34 and 58–64 days post-insemination by transrectal ultrasonography. Conception rates on days 28–34 and 58–64 were not different among GnRH (46.0%; 52/113 and 44.3%; 50/113), PGF2α (37.7%; 40/106 and 35.9%; 38/106) and control (49.5%; 52/105 and 47.6%; 50/105) groups. However, conception rates were lower (P = 0.02) in oxytocin (31.1%; 33/106 and 30.2%; 32/106) than in GnRH and control groups on days 28–34 and 58–64. Other covariant factors, such as milk production, days in milk (DIM), breed, parity, service number did not affect the conception rate. Thus, there were no beneficial effects of treatments with GnRH and PGF2α at the time of AI, and oxytocin had an adverse effect on CR in lactating dairy cows in this study.

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Inhibition of mouse fertilization in vivo by intra-oviductal injection of an anti-equatorin monoclonal antibody

Reproduction ◽

10.1530/rep.0.1220649 ◽

2001 ◽

pp. 649-655 ◽

Cited By ~ 19

Author(s):

K Yoshinaga ◽

DK Saxena ◽

T Oh-oka ◽

I Tanii ◽

K Toshimori

Keyword(s):

Monoclonal Antibody ◽

Reproductive Tract ◽

Female Reproductive Tract ◽

Pathological Changes ◽

Histological Studies ◽

Control Side ◽

Mammalian Sperm ◽

The Right ◽

And Control

The monoclonal antibody mMN9 recognizes an antigenic molecule, equatorin, which is localized at the equatorial segment of the mammalian sperm acrosome. Our previous results using an IVF system indicated that mMN9 blocked sperm-oocyte fusion. Antibody-containing and control solutions were injected directly into the right and left oviductal ampullae, respectively, of anaesthetized female mice to assess the effect of mMN9 on fertilization in vivo. After hCG treatment, the females were mated, and their oviductal eggs and implanted embryos were examined. mMN9 was retained in the oviductal lumen at 20 h after injection. The rates of fertilization and concomitant pregnancy were significantly lower than in the control side (P < 0.05). In addition, histological studies showed no evidence of pathological changes in the female reproductive tract after the injections. These results indicate that mMN9 inhibits mouse fertilization significantly under in vivo conditions and that this injection method should be useful for studying the effects of antibodies and agents on fertilization in vivo.

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Steroid sulfotransferases and steroid sulfate sulfatases: characteristics and biological roles

Canadian Journal of Biochemistry and Cell Biology ◽

10.1139/o85-141 ◽

1985 ◽

Vol 63 (11) ◽

pp. 1127-1144 ◽

Cited By ~ 152

Author(s):

R. Hobkirk

Keyword(s):

Biological Control ◽

Reproductive Tract ◽

Female Reproductive Tract ◽

Control Mechanisms ◽

Regulatory Enzymes ◽

Mammalian Tissues ◽

Growth Promoting ◽

Steroid Sulfate ◽

Substrate Affinities ◽

Steroid Structure

This review discusses the biological roles of steroid sulfotransferase enzymes (ST's) and steroid sulfate sulfohydrolases (sulfatases) mainly in mammalian tissues. In addition, some consideration is given to certain characteristics of these enzymes and, where possible, to their biological control. A considerable number of ST's of varying specificities, substrate affinities, and kinetics appear to exist. Several of these possess the properties of regulatory enzymes. ST's which act upon estrogen in reproductive tissues, such as uterus, are of particularly high affinity, appear to be under some biological control, and may exert important effects upon estrogen action. Although biosynthetic pathways involving steroid sulfate intermediates have been described, their importance is difficult to determine. The presence of an esterified sulfate group on a steroid molecule may markedly affect the action of enzymes, such as hydroxylases, upon the steroid structure in both a qualitative and quantitative sense. The number of different steroid sulfatases is not well understood. A sterol sulfatase present in the female reproductive tract appears capable of destabilizing the sperm head membrane by hydrolyzing sterol sulfates necessary for its integrity, and hence enabling the fusion of sperm and ovum. Other sulfatases may utilize blood-borne steroid sulfates for the ultimate production of estrogen which, in fetal membranes, could play a role in parturition and, in breast tumours, could function as a growth promoting agent. Brain sulfatases could possibly produce steroid hormones for purposes of tissue differentiation and (or) feedback control mechanisms, but this is not firmly established.

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Natural Immunity to HIV: A Delicate Balance between Strength and Control

Clinical and Developmental Immunology ◽

10.1155/2012/875821 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 12

Author(s):

Johanne Poudrier ◽

Valérie Thibodeau ◽

Michel Roger

Keyword(s):

Sex Workers ◽

Reproductive Tract ◽

Female Reproductive Tract ◽

Natural Immunity ◽

Hiv Resistance ◽

Point Of Entry ◽

Inflammatory Conditions ◽

Effective Interventions ◽

And Control ◽

Hiv Negative

Understanding how the mucosal immune system in the human female reproductive tract might prevent or facilitate HIV infection has important implications for the design of effective interventions. We and others have established cohorts of highly-exposed, HIV-seronegative individuals, such as HIV-uninfected commercial sex workers, who have remained HIV-negative after more than 5 years of active prostitution. Observations obtained in studies of such individuals, who represent a model of natural immunity to HIV, indicate that HIV resistance may be associated with the host’s capacity to preserve systemic integrity by constraining immune activity and controlling inflammatory conditions at the mucosal point of entry. This likely necessitates the orchestration of balanced, first-line and adaptive immune responses.

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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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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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