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Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sperm-rich semen and washed porcine spermatozoa were incubated for up to 2 hr either in utero in the presence of oviduct fluid or in vitro at 37 degrees C. Sperm lipids were extracted and separated into phospholipid and neutral lipid fractions. Eleven phospholipid and five neutral lipid fatty acids were identified and quantified using GC and GC-MS. The percentage of 22:5n6, the major phospholipid fatty acid, decreased slightly but significantly during 1.5 hr of in utero incubation (41.2-38.0%), but after 2.0 hr of in utero incubation no significant difference was observed (40.0%). None of the phospholipid fatty acids changed in concentration during in vitro incubation. The mole ratio of phospholipid to phospholipid fatty acid (1.00:1.27) did not change during incubation. The levels of neutral lipid-bound 14:0 decreased (43.5% to 31.8%) and that of 18:0 increased (11.1% to 18.2%) during in utero incubation. Similar but less pronounced changes were observed during in vitro incubation. (43.5% to 36.0%; and 11.1% to 15.8%, respectively). Two major sterols, cholesterol (73%) and desmosterol (27%) were identified by gas chromatography-mass spectrometry. The mole ratio of phospholipid to sterol (2.47:1:00) did not change during incubation.
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PMID:Effects of in utero and in vitro incubation on the lipid-bound fatty acids and sterols of porcine spermatozoa. 350 67

Actin in the sperm head of Talpa europaea was observed by immunofluorescence and immunoelectron microscopy. The indirect immunofluorescence technique, using both anti-actin and DNase anti-DNase methods, showed a shining fluorescent band around the sperm head in some spermatozoa, whereas in others the fluorescence was found in the postacrosomal region. Since no labeling was detected in sperms treated with NBD-phallacidin, it is likely that mature mole sperms contain G-actin but not F-actin. The results of electron microscopy indicated the deposition of the anti-actin antibodies in two places in mole spermatozoa: the postacrosomal region and the nuclear segment of the acrosome. In the first case, the actin was localized in the space between the outer surface of the postacrosomal sheath and the plasma membrane; in the second one, the actin was localized in the space between the outer acrosomal membrane and the plasma membrane. The significance of the presence of actin and its role(s) during fertilization are discussed.
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PMID:Immunocytochemical localization of actin in the sperm head of Talpa europaea (Insectivora). 351 5

Complete mole is a form of natural allograft since it carries paternal genetic traits alone which differ antigenetically from those of the mother. Successful growth of mole is likely to be immunologically protected. Because the immune system is genetically controlled, the effect of HLA system on the development of androgenetic ova into moles is a subject of interest. In this study, HLA-A and -B specificities in the mole and its parent were compared with the ones of general population in Japan. Fifty-six molar tissues were used for absorption of HLA specificities determined by HLA typing of each patient and her husband. Results obtained were as follows. 1) HLA antigens were expressed on all molar tissues examined, and those antigen were derived selectively from paternal specificities, but not maternal one. 2) Fifty molar tissues had received the paternal haplotype and remaining six molar tissues had showed heterozygosity which were consistent with the paternal diplotype. Those suggested the fertilization of an empty egg by two spermatozoa. 3) A significant association was found with decreased frequency of HLA-Aw19 and HLA-Bw22 in the molar tissues (3.6% and 2.7%) compared with general population (16.4% and 11.5%). 4) The compatibility of HLA-A and -B types among moles with sequelae and the parents was higher(81%) than the estimated value(68%) in the control families. As a result, HLA analysis was useful for distinction of zygosity of molar tissues. Decreased frequencies of HLA-Aw19 and -Bw22 in the mole were assumed to be resulted from the wastage of androgenetic ova.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Studies on HLA specificities in molar conceptions]. 367 84

A heat-stable microtubule-associated protein (MAP) with molecular weight of 190,000, termed 190-kD MAP, was purified from bovine adrenal cortex. This MAP showed the same level of ability to promote tubulin polymerization as did MAP2 and tau from mammalian brains. Relatively high amounts of 190-kD MAP could bind to microtubules reconstituted in the presence of taxol. At maximum 1 mol of 190-kD MAP could bind to 2.3 mol of tubulin. 190-kD MAP was phosphorylated by a cAMP-dependent protein kinase prepared from sea urchin spermatozoa and by protein kinase(s) present in the microtubule protein fraction prepared from mammalian brains. The maximal numbers of incorporated phosphate were approximately 0.2 and approximately 0.4 mol per mole of 190-kD MAP, respectively. These values were lower than that of MAP2, which could be heavily phosphorylated by the endogenous protein kinase(s) up to 5 mol per mole of MAP2 under the same assay condition. 190-kD MAP had no effects on the low-shear viscosity of actin and did not induce an increase in turbidity of the actin solution. It was also revealed that 190-kD MAP does not cosediment with actin filaments. These data clearly show that, distinct from MAP2 and tau, this MAP does not interact with actin. Electron microscopic observation of the rotary-shadowed images of 190-kD MAP showed the molecular shape to be a long, thin, flexible rod with a contour length of approximately 100 nm. Quick-freeze, deep-etch replicas of the microtubules reconstituted from 190-kD MAP and brain tubulin revealed many cross-bridges connecting microtubules with each other.
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PMID:Purification and characterization of a 190-kD microtubule-associated protein from bovine adrenal cortex. 378 89

There are two main mechanisms of origin for complete hydatidiform mole: (a) fertilization of an empty egg by a haploid sperm followed by duplication (monospermic mole); and (b) fertilization of such an egg by two haploid spermatozoa (dispermic mole). The former is inevitably homozygous (homozygous mole), whereas the latter may be heterozygous for a given genetic marker (heterozygous mole). A recent cytogenetic study showed that three cases of choriocarcinoma were undoubtedly heterozygous, which prompted us to compare the incidence of postmolar sequelae between patients with homozygous moles and those with heterozygous moles. Making use of chromosomal heteromorphisms and human lymphocyte antigen and phosphoglucuromutase 1 polymorphisms, we established the androgenetic origin of a complete mole in 49 of 56 cases. Homozygosity was confirmed in 21 moles, and heterozygosity was confirmed in five. Three of five patients with heterozygous moles developed postmolar trophoblastic disease, whereas none of the 21 patients with homozygous moles suffered postmolar trophoblastic disease except one who showed signs of degenerating residual trophoblasts. Consistent with this observation is the fact that all of the four destructive moles studied here were of dispermic origin. Thus, heterozygous moles seem to have a higher malignant potential than do homozygous moles.
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PMID:Malignant potential of homozygous and heterozygous complete moles. 631 83

Complete mole is an abnormal human pregnancy which is characterized by grossly swollen villi in the absence of a fetus. It has been widely accepted that of all forms of pregnancy that leads to choriocarcinoma, the risk associated with moles is by far the highest, being 2000 to 4000 times greater than that of normal pregnancy or abortion (1). However there has been no direct proof that choriocarcinoma indeed derives from complete mole. In the present study, to shed some light on the genesis of trophoblastic tumor, chromosome, HLA and PGM1 polymorphisms were examined for complete moles and choriocarcinomas. As a result, it has been ascertained that complete mole was androgenetic in origin; the entire genome of the molar conceptus was paternally derived. More than ninety percent of cases were resulted from fertilization of an empty egg (i.e. the nucleus was either eliminated or inactivated) by a haploid sperm. The paternally derived haploid set then duplicated without cytokinesis and restored diploidy. This class of moles had invariably a 46, XX karyotype and was completely homozygous for any genetic markers. Fertilization of an empty egg by two spermatozoa could elucidate remaining cases. The androgenetic origin of complete mole has provided us with a means to directly evaluate the relationship between choriocarcinomas and their putative forerunners; complete homozygosity and exclusive inheritance of a paternal genome would be expected if the tumor arose from complete mole derived from the former mechanism. However, the heterozygosity observed in choriocarcinoma cells suggested that the tumor did not arise from moles which originated from the fertilization of an empty egg by a haploid sperm.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[A study for the genesis of trophoblastic tumor, with reference to its androgenetic origin]. 632 16

A survey of species differences in the duration of capacitation, T, has revealed that they closely correlate with sperm cholesterol/phospholipid mole ratios, R : T = 8R - 1 (r2 = 0.97, in which r is Pearson's correlation coefficient). Because uterine cells displayed low relative cholesterol concentrations, spermatozoa evidently experience a negative external cholesterol gradient (positive phospholipid gradient) during capacitation. A decrease in sperm R-value is suggested, therefore, to accompany capacitation. The idea received strong support from a kinetic analysis of capacitation intervals, based on the rate of cholesterol efflux from sperm cells in utero. Lipid-binding serum proteins in uterine fluid are attributed with removing a sterol barrier to the Ca2+-facilitated membrane fusion that initiates the acrosome reaction. Tight cell junctions prevent permeation of the male generative tract by these proteins (capacitation factors). Furthermore, seminal plasma contains a decapacitation factor, identified as a membrane vesicle (cholesterol donor) component of this fluid, that reverses capacitation. Initiation of the sperm acrosome reaction among mammals could be the first fusion process found to be physiologically modulated through the membrane bilayer cholesterol level.
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PMID:Timing of fertilization in mammals: sperm cholesterol/phospholipid ratio as a determinant of the capacitation interval. 695 Mar 97

Reproductive tracts and spermatozoa from reproductively active and reproductively suppressed non-breeding males from two species of eusocial African mole-rats Cryptomys damarensis and Heterocephalus glaber were examined. In two captive colonies of Heterocephalus glaber, reproductive tracts from seven non-breeding males removed from their colonies, and housed singly for 5-6 weeks to cause reproductive activation, were compared with reproductive tracts from seven non-breeding males. The body weight of the separated, reproductively active males increased significantly (P < 0.01), and the mean testis weights relative to body weight of the reproductively active males were significantly larger (P < 0.05) than those of non-breeding males. The number of spermatozoa, in one half of the reproductive tract, was higher in active males than in non-breeding males (mean +/- SEM: 8.59 x 10(6) +/- 2.69 x 10(6) versus 1.78 x 10(6) +/- 1.43 x 10(6), respectively; P < 0.05). In addition, six of the seven reproductively active males, but only two of seven non-breeding males, had motile spermatozoa. A total of 28 wild Cryptomys damarensis from two colonies were examined in the field. The testis weights relative to body weight of breeding males (n = 7) were higher than those of non-breeding males (n = 19; P < 0.01), but the number of spermatozoa did not differ significantly between the two groups (0.13 x 10(6) +/- 0.06 x 10(6), n = 7 versus 0.29 x 10(6) +/- 0.14 x 10(6), n = 21, respectively). Breeding and non-breeding males produced similar numbers of motile spermatozoa.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Investigation of numbers and motility of spermatozoa in reproductively active and socially suppressed males of two eusocial African mole-rats, the naked mole-rat (Heterocephalus glaber) and the Damaraland mole-rat (Cryptomys damarensis). 802 57

The testicular structure of the wild caught naked mole rat was studied. It comprises of a large volume of lipid-rich interstitial cells of Leydig among which are few scattered seminiferous tubules. In addition, the interstitial cells possess elongated mitochondria and vast network of smooth endoplasmic reticulum (sER). The Golgi apparatus (GA) apparently is not conspicuous or well developed. All stages of spermatogenesis occur in the seminiferous tubules although the mature forms (secondary spermatocytes, spermatids and spermatozoa) are few. Sertoli cells show an irregular nucleus, mitochondria oriented perpendicular to the basement membrane, a vast network of endoplasmic reticulum with sER as the predominant form and lipid droplets. The ultrastructural features of Leydig cells seem to suggest a steroidogenic capacity although the vast accumulation of lipid droplets may imply impaired utilisation of cholesterol reservoir as a result of pituitary hormonal imbalance or (and) the local paracrine influence by Sertoli cells. The cause of slow-down in spermatogenesis is still unclear but may also be under the influence of pheromonal cues or the local paracrine control. Sertoli cell features point towards a role of synthesis and secretion.
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PMID:Ultrastructural study of the testis of non-breeding naked mole-rat (Heterocephalus glaber, Ruppell). 825 Feb 73

The lipid composition of the sperm membrane has a significant effect upon the functional characteristics of spermatozoa. In the present study we investigated the fatty acid (FA) composition of subpopulations of spermatozoa separated on a discontinuous Percoll gradient (47:90%) and the FA composition of phospholipids (PL) of sperm heads and tails in both normal and abnormal semen samples. In normozoospermic samples, polyunsaturated fatty acids (PUFA) represented 34.0 +/- 1.3 (mean +/- SE, mole %) and 25.6 +/- 1.2% of total FA of PL of the 47 and 90% Percoll fractions respectively. Docosahexaenoic acid (22:6omega3, DHA) contributed to more than 60% of total PUFA. DHA was significantly lower in both the 47% (P < 0.05) and the 90% (P < 0.01) Percoll fractions of oligozoospermic samples and in the 90% Percoll layer of asthenozoospermic samples (P < 0.01), compared with normozoospermic samples. The omega6/omega3 ratio was significantly increased in both Percoll fractions of samples with oligozoospermia (47%, P < 0.001 and 90%, P < 0.001) or with asthenozoospermia (47%, P < 0.05 and 90%, P < 0.001) compared with normozoospermic samples. The oxidative potential index (OPI) of spermatozoa recovered from the 47% Percoll layer was significantly higher (P < 0.0001) than of those recovered from the 90% Percoll. Mean melting point (MMP), an index of membrane fluidity, was significantly lower in head than in tails (P < 0.01) of spermatozoa, and also in both the 47% (P < 0.01) and 90% (P < 0.001) Percoll fractions of normozoospermic samples in comparison with oligozoospermic samples. The MMP was significantly higher (P < 0.05) in samples of patients with idiopathic oligo/asthenozoospermia, varicocele, and male accessory gland infection (MAGI). These differences in FA composition of PL in subpopulations of human spermatozoa, and in their heads and tails may be related to sperm maturity and to differences in physiological function.
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PMID:The fatty acid composition of phospholipids of spermatozoa from infertile patients. 954 67


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