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Results for “Follicle selection”

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PubMed1978

Pure crystalline estradiol pellet implantation for contraception.

The subcutaneous implantation of estradiol pellets was found to be a simple and effective contraceptive method with good patient acceptance and minimal untoward effects. The pellets (25 mg each) were implanted through a Kearn's trocar into the abdominal wall, 2.5 to 5 cm above and parallel to Poupart's ligament. The regimen began with four pellets, and the dose was maintained or decreased by one pellet every 6 months (four, three, two, one). A potent progestogen was utilized monthly for induction of withdrawal bleeding. Altogether, 236 patients were followed for a total of 1,060 courses in 6,360 cycles (489,02 woman-years). Two pregnancies occurred during therapy. Pearl's index was 0.37. No significant alterations occurred in body weight and blood pressure. Glucose tolerance test, standard blood profiles, and Papanicolaou smears were normal during therapy. No cases of thrombophlebitis, blurred vision, headaches, gastric symptoms, or amenorrhea-galactorrhea were observed. The suppression of ovulation was confirmed by endometrial biopsies, basal body temperature, and serum follicle-stimulating hormone, luteinizing hormone, estradiol, and progesterone in a selected group of patients.

Abdominal Muscles↗
PubMed1977

Identification of human peripheral T cell antigens.

A new type of differentiation antigens on human T cells was demonstrated by using a heterologous anti-human T cell serum (ATS). This type of antigen, referred to as human peripheral T cell antigen (HPTA), was found on peripheral T cells and medullary thymocytes, but not on cortical thymocytes and B cells. The percentage of ATS-reactive lymphocytes in human peripheral lymphoid organs was correlated with that of cells rosetting with sheep erythrocytes, but contrasted with the number of B cells defined by the presence of a complement (C) receptor or by rabbit anti-human B cell serum (ABS). ATS also reacted with T cells purified by nylon fiber column filtration but ABS did not. Chronic lymphocytic leukemia cells rosetted with either sheep erythrocytes or erythrocyte-antibody-complement complexes were lysed by ATS and ABS, respectively. Mitogenic responses of blood lymphocytes to phytohemagglutinin (PHA) and concanavalin-A (Con A) were abrogated by treating them with ATS and C, whereas ABS suppressed only their response to Con A. Although numerous thymus cells rosetted with SRBC, only 14% were reactive with ATS. Quantitative absorption studies demonstrated that HPTA content of the thymus cells was much lower than that of lymph node cells. Anatomical localization of ATS-reactive lymphocytes in human lymphoid organs studied by immunofluorescence indicated that they were present in the thymus-dependent paracortical areas of lymph node and in the medullary region of thymus. ABS, on the other hand, did not stain thymocytes but reacted selectively with the cells located in the lymphoid follicles of lymph node. These data, together with that from cell suspension studies, confirmed that HPTA were shared between medullary thymocytes and peripheral T cells.

Antigens↗
PubMed1977

Influence of synthetic thyrotropin-releasing hormone tartrate monohydrate on plasma gonadotropin concentration of normal males.

Synthetic thyrotropin-releasing hormone (TRH) tartrate monohydrate was administered by rapid intravenous injection to nine normal males. Plasma thyroid-stimulating hormone (TSH), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were measured before and at selected periods after TRH injection. The mean plasma TSH value immediately prior to TRH injection was 3.5 muU/ml and the level 15 min after injection was 14.8 muU/ml. The mean plasma LH value immediately prior to TRH injection was 8.0 mIU/ml and the level 15 min after injection was 15.0 mIU/ml. The latter elevation was statistically significant (p less than 0.01), although it was just above the upper normal range. The mean plasma FSH value immediately prior to TRH injecion was 7.7 mIU/ml, and a significant difference was not observed after TRH administration. These results revealed that synthetic TRH tartrate monohydrate influenced the release of LH from the anterior pituitary.

Adult↗
PubMed1979

Ovarian function and the immune system.

A hypothesis is presented on the interaction between the immune system and ovary in the regulation of the reproductive system and in the origin of some of its disorders. It has been suggested that the beginning, duration and age dependent failure of ovarian ovulatory function depends among other things on the adequate relationship between the immune system and approriate ovarian target structures. The cyclicity of ovarian function is considered to be primarily dependent on the induction of a specific cyclic immune response to the ovary. Similarly, the selection of a species-specific number of ovulating follicles during sexual maturity is thought to be ensured by immune mechanisms. This hypothesis, on the role of the immune system in regulation of ovulatory ovarian function respects the physiological effect of gonadotropins and steroids on the ovarian structures. The interaction between the ovary and the hypothalamus-pituitary system appears to be modulated by the relationship between the ovary and the immune system.

Aging↗
PubMed1978

Role of the immune system in regulation of ovarian function-hypothesis.

A hypothesis is presented on the interaction between the immune system and ovary in the regulation of the reproductive system and in the origin of some of its disorders. The cyclicity of ovarian function is considered to be primarily dependent on the induction of a specific cyclic immune response to the ovary. Similarly, the selection of a species-specific number of ovulating follicles during sexual maturity is thought to be ensured by immune mechanisms.

Animals↗
PubMed1979

[Pineal teratoma--case report (author's transl)].

A 3-year-old boy had a history of nausea and vomiting for 1 month. After two episodes of tonic cramp, he became drowsy and then semicomatous. Physical examination on admission revealed a dehydrated semicomatous boy with fixed, dilated pupils of equal size, horizontal nystagmus, and left hemiparesis with bilateral Babinski signs. Plain skull films showed a separation of coronal and sagittal sutures. A high density area surrounded by cyst was found in the pineal region in CT scan. Angiography demonstrated stretching of the posterior choroidal arteries, backward displacement of the Galen, the posterior mesencephalic and the precentral vein. The right occipital transtentorial approach was selected to remove the tumor totally. Histology revealed epidermis, hair follicle, sebaceus and sweat glands, columar gland, bone, cartilage, muscle, fatty tissue, nervous tissue, and connective tissue, indicating a pineal teratoma. There was no evidence of germinoma.

Brain Neoplasms↗
PubMed2025

Evaluating Selective Quality Control in Mammalian Oogenesis: Evidence and Opportunities.

The formation and maintenance of the finite mammalian ovarian reserve are critical for fertility and species survival. Genetic and developmental studies have uncovered various mechanisms underlying oocyte development and maturation, revealing two curious features of the ovarian germline: (a) The establishment of the follicle reserve involves an initial massive overproduction of oocyte precursors, and (b) the total number of ovulated oocytes across an animal's fertile lifetime is a very small proportion of the initial ovarian reserve. Many have proposed that this indicates the existence of selective quality control to ensure gamete fitness. Here, we review the findings underlying the hypotheses for germline quality control during prepubertal development, homeostatic fertility, and reproductive aging. We evaluate whether the existing evidence base distinguishes the active selection of specific germ cell subsets from neutral dynamics. Throughout, we discuss strategies for applying statistical frameworks to evaluate selection in oogenesis and the implications of neutrality versus selection at various points in oocyte development.

Oogenesis↗
PubMed1979

Germinal vesicle configurations and patterns of polypeptide synthesis of procine oocytes from antral follicles of different size, as related to their competency for spontaneous maturation.

The cytogenetic configurations of germinal vesicle (gv) chromatin were analyzed for pools of porcine oocytes harvested from small (1.0-2.0 mm), medium (3.0-5.0 mm), and large (6.0-10.0 mm) antral follicles. Groups of oocytes from these follicular classes also were examined by high-resolution, two-dimensional, polyacrylamide gel electrophoresis to compare their patterns of polypeptide synthesis. The results show a high incidence of gross and cytogenetic degeneration among oocytes from small antral follicles as compared with those from medium or lage follicles. Pools of oocytes could be separated, on the basis of gross morphology and integrity of adherent granulosa cells, into two classes: "Type A" which appeared normal, and "type B" which appeared to be atretic. Among selected "type A" oocytes a particular chromatin configuration, termed "fibrous" characterizes the gv of oocytes from small follicles; whereas a different configuration, termed "diffuse," characterizes the gv of oocytes from large follicles. The patterns of polypeptide synthesis were markedly different for samples of "type A" oocytes of the three follicular classes; and the patterns for oocytes from medium and large follicles were more similar to each other than to patterns for oocytes from slall follicles. The incidences of maturational development beyond the gv stage in vitro were similar for "type A" oocytes from the three follicular classes (i.e., 66% to 82% maturation); although "type B" oocytes underwent maturation beyond the gv at a significantly reduced incidence (i.e., 20% to 29% maturation). "Type A" oocytes from large follicles completed maturation in vitro (i.e., underwent the first meiotic division) at a significantly higher incidence (55%) than did oocytes from small (11% to 20%) or medium (16%) follicles. Our findings are consistent with the hypotheses that a high proportion of oocytes from small antral follicles are atretic, and that a developmental program controls the molecular and cytogenetic changes occurring in porcine oocytes during follicular growth. These changes appear to be highly correlated with the acquisition of competency to complete maturation in vitro, and possibly also are required for normal fertilization and embryogenesis.

Animals↗
PubMed2026

Large-scale low-coverage whole-genome sequencing reveals the genetic architecture of wool and growth traits in fine-wool sheep.

Breeding sheep with superior growth performance and wool quality is essential for the sustainability of the fine-wool sheep industry. In this study, we perform low-coverage whole-genome sequencing (lcWGS) on 3842 individuals from 5 sheep breeds (4 fine-wool and 1 semi-fine wool) and generate a large genomic dataset. By comparing these breeds with coarse-wool sheep, we characterize the genomic landscape and selection signatures of fine-wool sheep. We identify several known functional genes associated with hair follicle development and skin morphology, including EGFR, KRT74, EDAR, EREG, and GLI2. Furthermore, GWAS of 19 traits identifies 156 candidate genes significantly associated with growth and wool characteristics, including LCORL for body size, EGFR for clean wool yield, and PRDM1 for fiber diameter. Notably, EGFR is detected in both GWAS and selection signature analyses, indicating its important role in phenotype formation and historical selection. Overall, our findings reveal the genetic basis of growth and wool traits in fine-wool and semi-fine wool sheep, highlight EGFR, LCORL, and PRDM1 as candidate genes, and provide valuable genomic resources and candidate markers for future functional validation and molecular breeding.

Body size↗
PubMed1978

Staging profile of hypofertile male subjects.

Thirty-four hypofertile male subjects with either oligospermia or azoospermia underwent infertility evaluation with assay of serum follicle-stimulating hormone, luteinizing hormone, testosterone and testicular biopsy. Cytogenetic analysis of testicular tissue and peripheral leukocytes was competed on 11 patients. Fifteen male subjects underwnet bilateral contrast vasography. These studies permitted segregation of the hypofertile male population from those with post-germinal hypofertility, primary germinal hypofertility or pre-germinal hypofertility. Retrospective analysis indicates that segregation of the hypofertile male population permits optimum selection for treatment intervention.

Biopsy↗
PubMed1978

Suppressive effect of 1,2-dibromo-3-chloropropane on human spermatogenesis.

Azoospermia was diagnosed in six factory workers who had been chronically exposed to 1,2-dibromo-3-chloropropane. Infertility was the presenting symptom in two patients and a decrease in libido or impotence characterized the others. Hormone studies revealed elevated plasma follicle-stimulating hormone levels and normal plasma luteinizing hormone and testosterone concentrations. Testicular biopsy showed selective atrophy of the germinal epithelium, intact Sertoli cells, and a normal appearance of a relatively increased number of Leydig cells.

Adult↗
PubMed1979

Bromocriptine in the treatment of hypogonadism and male impotence.

A rapid, practical diagnostic scheme is the key to selecting proper candidates for treatment with bromocriptine. The evaluation centres around assays for prolactin and follicle stimulating hormone, polytomography and computerised axial tomography of the sella turcica and parasellar regions, and the ergot alkaloid, bromocriptine. Additionally, bromocriptine is of significant value in the treatment of men and women with hypogonadotrophic hypogonadism. Approximately 80% of patients with hypogonadotrophic hypogadism and hyperprolactinaemia will respond favorably to bromocriptine therapy. In women who conceive during such treatment there appears to be no increase in the rate of spontaneous abortion, of multiple gestations or of congenital anomalies. Bromocriptine appears to be of little value in the treatment of male impotence unless hyperprolactinaemia is a component of the disease. Side affects are usually mild and transient. Following the discontinuation of therapy most patients have a recurrence of hyperprolactinaemia and hypogonadism.

Bromocriptine↗
PubMed1979

Ultrastructural study of the follicle cells in the freshwater gastropod Viviparus viviparus L.

The morphology and the role of the follicle cells of Viviparus viviparus were examined by means of light and electron microscopy. The follicle cells appear to contain glycogen and fat, and often lysosomes or heterogeneous inclusions. Therefore, they seem to be active in phagocytosis and storage. They are probably involved in the nutrition of the oocyte. Their role in the formation of a selectively permeable barrier is discussed.

Animals↗
PubMed1976

A microbial etiology of acne?

The view is advanced that sebum as originally produced must contain materials, other than lipids, which may serve as a selective substrate for growth of bacteria and yeasts. Growth of large numbers of P. acnes and P. granulosum in some follicles is considered to place those follicles at risk of undergoing pathological changes. Deleterious products of bacterial growth could be not only lipase and free fatty acids, but also other enzymes as well as bacterial antigens and unspecified toxins or irritants. The possibility is suggested that follicles heavily infested with P. acnes and P. granulosum may be identified by their reddish fluorescence under ultraviolet light, thus permitting identification and study of those which are at risk. Antibiotics may be helpful in reducing the formation of harmful bacterial products during continued growth of the organisms. The eventually self-limiting nature of the disease may be due to the immune response to bacterial products, or to an accommodation of the follicular epithelium to the long-continued presence of irritant materials within the follicle.

Acne Vulgaris↗
PubMed1977

Studies on the proteins of Poekilocerus pictus. III-changes taking place in the haemolymph protein during maturation of male.

In all 7 protein fractions have been detected in the haemolymph of Poekilocerus pictus by the Polyacrylamide gel disc electrophoresis. Out of seven protein fractions, four fractions i.e. 3, 4, 5 and 6 take major role in the maturation of testis. Accumulation of proteins has been observed in the castrated insect. The concentration of the protein decreases and the size of the testis follicle remains small as compared to the normal male in the allatectomised insect. It is concluded that the proteins are selectively incorporated in the testis. It also appears that the synthesis of proteins and the maturation of testis is controlled by the allatum.

Animals↗
PubMed1979

Effect of dibromochloropropane on human testicular function.

Severe impairment of spermatogenesis was found in 18 (78%) of 23 workers after exposure to 1,2-dibromo-3-chloropropane (DBCP). Azoospermia associated with elevated plasma follicle-stimulating hormone was diagnosed in 12 workers whose exposure time to DBCP varied from 100 to greater than 6,000 h. Oligospermia and normal plasma follicle-stimulating hormone were found in six employees with exposure times between 34 and 95 h. Plasma luteinizing hormone, testosterone and thyroxine were within the normal range. Testicular biopsy showed selective atrophy of the germinal epithelium, intact Sertoli cells and normal appearance of Leydig cells. The mechanism and potential reversibility of these testicular changes are still to be evaluated.

Adult↗
PubMed1979

Hormone interactions in the Sertoli cells.

The effects of follicle-stimulating hormone (FSH) and testosterone in rat Sertoli cells were investigated in vitro by means of isolated cell populations. The Sertoli cells selectively bind FSH, and respond to FSH stimulation with increased accumulation of endogenous cyclic AMP and secretion of androgen-binding protein (ABP). FSH binding and cyclic AMP response in the Sertoli cells change dramatically during sexual maturation. Cyclic AMP response decreases despite an increase in FSH-binding receptors per cell. Evidence has been provided for the existence of cytoplasmic and nuclear androgen receptors and chromatin acceptor-sites that specifically bind the androgen-receptor complex in the Sertoli cells. A model has been proposed for the hormonal interactions in the seminiferous tubule and the possible role of Sertoli cells in mediating the hormonal effects on spermatogenesis.

Animals↗