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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present SEM and TEM study clearly indicated that the epithelial cells of the ampulla vasis deferentis of the dog are capable of performing phagocytosis of degraded spermatozoa and even inert latex beads as in other animals described previously and further supported our working hypothesis that epithelial phagocytosis may be a common event in the vas deferens of mammals, though its precise significance remains to be clarified.
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PMID:Scanning and transmission electron microscopic study of the ampullary region of the dog vas deferens, with special reference to epithelial phagocytosis of spermatozoa and latex beads. 381 43

The adult cat oviduct was viewed by SEM and TEM as spermatozoa of the same species and inert latex beads were injected into its lumen. The present study demonstrates that nonciliated epithelial cells in extensive areas of the oviduct as well as luminal macrophages are capable of actively taking up both the spermatozoa and the latex beads in the manner of phagocytosis. The epithelial cells are thus able to eliminate foreign bodies including degenerating spermatozoa in order to scavenge the lumen, though the cellular mechanisms involved in their phagocytosic activity remain to be elucidated.
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PMID:Phagocytosis of spermatozoa and latex beads by the epithelial cell of the cat oviduct: combined SEM and TEM study. 383 15

The precise hormonal milieu required for quantitatively normal spermatogenesis in man is unclear. The authors previously have shown that both supraphysiologic dosages of human chorionic gonadotropin (hCG) and physiologic dosages of human luteinizing hormone (hLH) can reinitiate sperm production in short-term (four months) gonadotropin-suppressed normal men who have prepubertal FSH levels. To determine whether normal FSH levels were necessary to stimulate sperm production after a prolonged period of gonadotropin and testicular suppression, the authors administered hCG to four normal men whose endogenous gonadotropin levels and sperm production were suppressed by prolonged exogenous testosterone (T) administration. After a 3-month control period, all subjects received 200 mg of T enanthate intramuscularly (im) each week to suppress LH and FSH for a total of 9 months and until successive sperm concentrations (performed twice monthly) revealed azoospermia or severe oligozoospermia (mean sperm concentration less than 3 X 10(6) spermatozoa/ml) for 6 months. Then, while continuing the same dosage of T enanthate, all four men simultaneously received 5000 IU of hCG im three times weekly for 6 months, replacing LH-like activity and leaving FSH activity suppressed. The effect on sperm production of the selective FSH deficiency produced by hCG plus T administration after the period of prolonged gonadotropin suppression was determined. Exogenous T administration resulted in severe suppression of sperm concentrations from 79 +/- 7 X 10(6) spermatozoa/ml (mean +/- SEM) during the control period to 0.8 +/- 0.5 X 10(6)/ml after 12 weeks of T treatment.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Stimulation of sperm production by human chorionic gonadotropin after prolonged gonadotropin suppression in normal men. 392 31

The annual reproductive cycle of the male little brown bat, in contrast to seasonal reproductive patterns of other mammals, is differentiated by an asynchronous recrudescence of the testis and the accessory reproductive glands. Spermatogenesis occurs during the summer, whereas fully stimulated accessory organs, stored epididymal spermatozoa, and sexual behavior are expressed later during a mating period that extends, albeit interrupted by hibernation, from late summer until early spring. To investigate whether changes in high affinity androgen-binding activity in the circulation are related to the delayed renewal of the accessory organs, plasma sex steroid-binding protein (SBP) and total testosterone (T) levels were measured throughout the year. From these data and determinations of association constants for T binding to SBP and albumin at both hibernating (4 degrees C) and active (40 degrees C) temperatures, estimates of the unbound ("free") and albumin-bound T fractions were made and correlated with changes in the accessory reproductive organs. Plasma SBP concentrations (mean +/- SEM) exhibited wide seasonal fluctuations: they were baseline in May (10 +/- 2 nM) following spring arousal, increased dramatically in June (184 +/- 24 nM), and reached peak levels in early July (262 +/- 29 nM), where they remained until August. In late August they began to fall (104 +/- 23 nM) and then returned to baseline during the hibernation period (October-April). Although total T levels were also elevated in June, it appeared that the unbound ("free") and the unbound plus albumin-bound T fractions did not increase until late July. Since the accessory gland weights did not begin to increase until late July as well, it was concluded that increases in the unbound and albumin-bound T fractions may be an important factor in the recrudescence of the accessories and that increased SBP activity in early summer may play a role in the regression and delayed renewal of these organs. However, what factor(s) maintain the accessory glands, epididymal spermatozoa, and sexual behavior during the breeding and hibernation periods when all T fractions were low are, as yet, undetermined.
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PMID:Annual variations in plasma sex steroid-binding protein and testosterone concentrations in the adult male little brown bat: relation to the asynchronous recrudescence of the testis and accessory reproductive organs. 407 6

The presence of rabbit spermatozoa in the uterine horn of the doe over a 10-hr period induced an increase in the incorporation of leucine-14C and orotate-3H [from 230 +/- 50 to 520 +/- 32 and 146 +/- 41 to 432 +/- 40 (dpm 10(3) mg DNA; Mean +/- SEM)] into endometrial proteins and nucleic acids. The addition of actinomycin D or cyclohexamide significantly inhibited this process. The intraluminal administration of dibutyryl cyclic AMP (dbcAMP) (control group) induced an increase two times greater than that produced by spermatozoa. The increase in the incorporation of radioactive precursors into endometrial macromolecules induced by the spermatozoa is independent of the uterine carbonic anhydrase activation produced by this cell.
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PMID:Effect of rabbit spermatozoa on the incorporation of labeled precursors into endometrial macromolecules. 616 Aug 22

The concentration of glucose in the plasma of alloxan-diabetic rats was 23.4 +/- 0.86 mM (mean +/- SEM; n = 18), and the concentration of insulin was 11.4 +/- 1.67 microU/ml (mean +/- SEM; n = 17). The weights of the ventral prostate (0.45 +/- 0.03 vs. 0.72 +/- 0.04 g) and seminal vesicles (1.23 +/- 0.06 vs. 1.84 +/- 0.08 g) were decreased compared to control values and the rats lost body weight, but the weights of the testes were not significantly different from control values (3.14 +/- 0.08 vs. 3.23 +/- 0.14 g/pair). Similar changes were seen in streptozotocin-diabetic rats. The concentration of fructose (micromoles per g fresh wt) was greater in the coagulating gland of alloxan-diabetic (19.6 +/- 1.3; n = 17) than control rats (9.1 +/- 0.7; n = 18). The production of 14CO2 from D-[U-14C]glucose by spermatozoa or seminiferous tubules from diabetic rats was decreased compared to that in controls [28 +/- 3 vs. 53 +/- 6 nmol glucose converted/10(8) spermatozoa X 30 min (n = 8) and 0.81 +/- 0.03 vs. 1.08 +/- 0.03 mumol glucose converted/g fresh wt X 30 min (n = 7)]. There was no change in the production of lactate or 3HOH from D-[2-3H] glucose, and the presence of insulin (10 mU/ml) in the incubation had little effect. Rat epididymal spermatozoa took up 2-deoxy-D-glucose by a facilitated diffusion mechanism; the Km was about 0.2 mM, with a maximum velocity of about 0.10 nmol/10(6) spermatozoa X 10 sec. Neither alloxan-diabetes nor the presence of insulin (10 mU/ml) had an appreciable effect on these parameters.
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PMID:The effect of experimentally induced diabetes on the metabolism of glucose by seminiferous tubules and epididymal spermatozoa from the rat. 623 7

The fine structure of hibernating bat spermatozoa (Vesperugo savi and Rinolophus f.e.) has been studied by SEM and TEM, during their prolonged storage in female reproductive tract. The main morphological aspects of sperm portions: head, neck, middle piece, principal piece and terminal piece have been described. The Author besides comparisons with other mammalian species and Chiroptera, suggests some typical ultrastructural features of these Chiroptera, as the complete absence of vacuoles in the nuclear chromatin and corrugated structures in the post-acrosomal zone. Moreover electron-dense material in the subacrosomal space and three mitochondria in the neck were observed. Two areas of fusion between outer dense fibers 3 and 8 and the inner ends of the respective longitudinal columns of the fibrous sheath and asymmetrical arrangement of the outer dense fibers of the principal piece were found.
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PMID:[The fine structure of spermatozoa from Chiroptera]. 624 6

Epidermal growth factor-like activity (EGF-LA) has been detected in human seminal plasma in concentrations of 5-150 ngeq/ml (36.4 +/- 2.1, mean +/- SEM), using a heterologous RRA with murine EGF. The samples were obtained from normal, subfertile and azoospermic men, aged 21-50 yr. No correlation was found between EGF concentration and age of donor, sperm count, sperm motility, or period of sexual abstinence before sample collection. High performance liquid chromatography of the seminal plasma resulted in a main peak of EGF-LA which eluted at 29% acetonitrile, compared to 33% for murine EGF. Microsomal membranes were prepared from several tissues from the human male reproductive tract and were tested for their ability to bind radioiodinated murine EGF. Specific EGF binding activity was detectable in testicular membrane preparations but was not detectable in membranes prepared from human prostate, seminal vesicle, epididymis, or spermatozoa. Endogenous EGF-LA was detectable in human testis, seminal vesicle, prostate, and epididymis.
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PMID:Identification of epidermal growth factor-like activity in human male reproductive tissues and fluids. 632 31

The state of the art of scanning electron microscopy in the field of human reproduction and the clinical significance of SEM techniques is described on the basis of 272 articles in which the SEM was a substantial instrument for research. The first section deals with reproductive cell biology, the various cell types and function in relation to cell surface microstructure. The second section outlines briefly various types of cell and tissue preparation, and advantages and pitfalls. The following sections describe the female reproductive system (including vulva, vaginal and ectocervical squamous epithelium, metaplastic epithelium of the transformation zone, endocervix and cervical mucus, endometrium, IUDs, tube, ovary, and mammary gland), the male reproductive system (male sex organs, spermatozoa) and the conceptus (placenta, embryogenesis). It is indicated where SEM has revealed deeper insights in the structure and function of reproductive cells and tissues and where SEM has a potential for clinical application. The following areas seem promising: the placenta (description of various classes of pathological conditions), the oviduct (description of two types of hydrosalpinges with different prognostic significance), cervical and ascites cytology (SEM's capacity for (early) discrimination of malignant cells) and spermatozoa (prognostic significance of classification with the use of X-ray micro-analysis). In many instances the same results can be obtained by routine LM and TEM. Because SEM does have potentially large diagnostic and prognostic powers further research is essential in order to establish the future role of SEM in the field of human reproduction.
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PMID:Clinical application of scanning electron microscopy in human reproduction. 637 76

The male partners of 68 couples exhibiting 5.1 +/- 0.3 (SEM) years of unexplained infertility were assessed using the conventional criteria of semen quality, the movement characteristics of the spermatozoa and the outcome of the zona-free hamster egg penetration test. After a follow-up period of 2.3 +/- 0.06 (SEM) years, 25 (37%) of these patients were found to have initiated a pregnancy, thereby permitting an analysis of those aspects of semen quality which most accurately predicted their subsequent fertility. A multivariate discriminant analysis revealed that the conventional semen profile, per se, was not of significant value in discriminating the incidence of pregnancy. However, significant discrimination (P = 0.0173) was obtained when the postcapacitation movement characteristics of the spermatozoa were incorporated into the analysis. The accuracy of this prognosis was further increased if either the duration of infertility or the outcome of the zona-free hamster egg penetration test was taken into consideration. Overall classifications of fertility were then 76.3% and 76.5% accurate, respectively. These results suggest that in vitro assessments of human sperm function are of significant value in evaluating male fertility.
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PMID:A prospective study of the relationship between semen quality and fertility in cases of unexplained infertility. 654 Jul 70


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