Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P50583 (asymmetrical)
 12,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During development membranous organelles first appeared in the primary spermatocytes of Ancylostoma. They were derived from the Golgi as two separate components. One component, an electron-dense spheroid, quickly fused with other newly-formed cup-shaped, membranous structures to form the asymmetrical organelles. Initially the membranous organelles had a homogeneous matrix but later became filled with quantities to 6- 8-nm filaments. Following the meiotic reduction divisions each cell assumed a bipolar configuration. The membranous organelles and mitochondria were confined to the broad anterior region while the non-membrane bound nucleus became located in the narrow posterior region. Golgi membranes, endoplasmic reticulum, and numerous ribosomes were sloughed from the main cell body. The filaments lost their association with the membranous organelles and attached to the plasma membrane while the membranous portion of each organelle became progressively more complex and assumed a peripheral position in the cytoplasm. The resulting spermatid, with its condensed, posteriorly-projected nucleus, and broad anterior cytoplasm, had a tadpolelike appearance. Subsequent to deposition in the female uterus the membranous organelles fused with the plasma membrane and the mature spermatozoa became pleomorphic and moved in an ameboid manner. Because the pseudopods in the mature cell originated in those areas where the filaments previously attached to the plasma membrane it is surmised that the filaments consist of, or contain, actin. The significance of the fusion of the membranous organelles with the sperm plasma membrane, however, remains unknown.
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PMID:Development and fate of the membranous organelles in spermatozoa of Ancylostoma caninum. 713 Nov 88

A new panel of monoclonal antibodies to the calf uterus estrogen receptor was prepared. Thirteen antibodies were characterized for their isotype and for the affinity for the antigen. These antibodies recognize the human receptor and can be used in Western blot analysis. The location of the epitopes was mapped on the antigen structure using synthetic fragments of estrogen receptor, and it was possible to group the antibodies in five groups. Many antibodies were useful for the purification of estrogen receptor from tissue extracts by immunoaffinity chromatography. The reciprocal inhibition of the antibodies for the antigen binding was measured with an immunoadsorption assay. This was maximal and symmetrical for antibody pairs within the same group, but was incomplete and, in some instances, asymmetrical between pairs of antibodies from different groups. One antibody was able to inhibit the estrogen receptor-DNA interaction, whereas two others were unable to recognize the receptor-DNA complexes. This new panel of antibodies is a useful addition to the existing tools for studying structure and function of the estrogen receptor.
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PMID:Characterization and epitope mapping of a new panel of monoclonal antibodies to estradiol receptor. 767 26

The objective of this prospective follow-up study was to evaluate the potential utility of three-dimensional (3D) ultrasound to differentiate intrauterine from extrauterine gestations. Fifty-four pregnancies with a gestational age <10 weeks and with an intrauterine gestational sac <5 mm in diameter formed the study group. The configuration of the endometrium in the frontal plane of the uterus was correlated to eventual pregnancy outcome. After exclusion of three patients with a poor 3D-image quality the endometrial shape was asymmetrical with regard to the median longitudinal axis of the uterus in 84% of intrauterine pregnancies, whereas the endometrium showed a symmetry in the frontal plane in 90% of extrauterine pregnancies (P = 0.0000001). Intrauterine fluid accumulation may distort the uterine cavity, thus being responsible for false-positive as well as false-negative results. The evaluation of the endometrial shape in the frontal plane appears to be a useful additional means to distinguish intrauterine from extrauterine pregnancies, especially when a gestational sac is not clearly demonstrated with conventional ultrasound.
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PMID:The shape of the endometrium evaluated with three-dimensional ultrasound: an additional predictor of extrauterine pregnancy. 955 55

The authors describe and illustrate two trematodes from Belize (Central America): Paramaritremopsis solielangi n. sp. from the small intestine of Arenaria interpres is characterised by a body length of 478 microm, two short and pre-acetabular caeca, part of the uterus in close association with the cirrus-sac and left caecum, vitelline glands in the shape of a horseshoe, a short pre-ovarian cirrus-sac containing a long, cylindrical, voluminous and unarmed cirrus (size when evaginated: 150 x 20-30 microm) and Microphallus kinsellai n. sp. from the caeca of Actitis macularia characterised by a body length of 370 microm and a phallus which is 30 microm in diameter and asymmetrical (basically a pad with a moderately developed accessory lobe) and a straight ejaculatory canal. Levinseniella carteretensis is another microphallid recovered from Arenaria interpres. The term of "phallus" is proposed to name the male copulatory organ which characterizes the Microphallinae.
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PMID:Paramaritremopsis solielangi n. sp. and Microphallus kinsellai n. sp. (Digenea: Microphallidae) parasites of Charadrii (Aves) of Belize (Central America). 1096 20

2.1. History and clinical-gynecological investigation including a Pap smear are the first step in the clarification. The history should make sure if there is in fact bleeding from the genital and not from the urological or the intestinal region. Drug intake should be recorded, and risk factors for the development of endometrial carcinoma should be considered. This will not affect further investigation. The clinical-gynecological investigation should prove the source of postmenopausal bleeding according to the anatomical site--uterine, infra-, or suprauterine. The causes of infrauterine bleeding may easily be diagnosed by means of inspection of the external genitalia and further by using a speculum. The causes of uterine bleeding are of major importance. Cytology and colposcopy, supported by bimanual investigation, exclude cervical carcinoma as a cause of bleeding. Atypical endometrial cells on the cytological smear arouse suspicion of endometrial carcinoma. 2.2. Transvaginal sonography (TVS) is the next step if the above-mentioned investigations are negative. Both adnexa should always be investigated and the findings sonographically documented, so that solid cystic masses in the adnexal area can be better identified as suprauterine causes of postmenopausal bleeding. Then the uterus should be investigated. Further procedures are decided from the results of measurement of the longitudinal section of the endometrium at the level of maximum endometrial thickness. If the endometrial thickness is _<4 mm, an observant attitude can be assumed. After 3 months the patient should be controlled against using TVS. If bleeding recurs or the endometrial thickness is >4 mm on TVS, the procedure given in subparagraph 2.3 should be followed. In case the endometrial thickness is >4mm or not measurable, a histomorphological investigation according to subparagraph 2.3 should be performed. In such cases, saline infusion sonohysterography(SIS) is useful as a simple method to supplement TVS. It can aid in the decision making as to which further, more invasive measures should be taken (endometrial biopsy/hysteroscopic resection). Computerized tomography or magnetic resonance imaging are, as a rule, not indicated in patients with postmenopausal bleeding. 2.3. A definite diagnosis is possible only on the basis of a histological investigation. If TVS or SS show evidence of a polypoid state, removal under hysteroscopic control is the diagnostic method of choice. In cases of symmetrical or asymmetrical thickening of the endometrium on SIS, a less invasive biopsy may be sufficient. If the biopsy specimen does not yield representative diagnostic material, one should proceed as described above. A fractionated curettage should as a rule not be performed solely, but in combination with hysteroscopy.
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PMID:[Guideline for the diagnosis of postmenopausal bleeding. PMPB Working Group of the SGGG]. 1097 Oct 89

The genetics of sex determination is a child of the twentieth century, which overturned the previously held view that sex was determined by the environment. The last quarter of the century witnessed an active search for sex-determining genes in mammals. Although successful, the modus operandi of these genes remained unknown, and the relationship between the sex-determining systems of mammals and other vertebrates remained enigmatic. To overcome these problems, scientists in the 21st century should heed William Bateson's counsel to treasure exceptions, for they point the way to progress. One exception to conventional concepts of sex determination is the bilaterally asymmetrical distribution of ovaries and testes in true hermaphroditism. Ovaries favour the left side in humans and the right side in mice. Observations suggesting that a reversal of asymmetry may occur with increasing organ size may point to a possible explanation. A reevaluation is also required regarding the beginning of sex differentiation, in view of mounting evidence of a sex difference in growth rates of early embryos. Another question to be settled is whether the function of SRY is confined to the fetal gonad. The recent demonstration that Sry induces cell proliferation in the fetal mouse gonad (Schmahl et al., 2000) further emphasizes the importance of differential growth in sex determination and differentiation. It is suggested that SRY represents an additional growth-promoting gene sequestered by mammals to enable the XY embryo to undergo male sex differentiation in the female hormonal environment of the uterus. An increased awareness of the relationship between growth and gonadal differentiation should lead to a better understanding of sex determination in mammals and an ability to relate the function of sex-determining genes to the effects of environmental factors. J. Exp. Zool. 290:484-489, 2001.
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PMID:Genetics of mammalian sex determination: some unloved exceptions. 1155 55

The parental origin of triploidy in 19 cases was examined by inheritance of DNA microsatellites and by methylation patterns of SNRPN or PW71 (where parents' blood was unavailable). The fetal and placental morphology on these cases was reviewed. The phenotype of the fetuses with non-mosaic triploidy was assessed in relation to the two types described by McFadden and Kalousek. Of the diandric fetuses three of the six showed mild-to-moderate symmetrical growth retardation and the other three had growth characteristics in accordance with their gestational ages. This study would suggest the fetal triploid 'Type 1' definition be modified to 'well grown to moderate symmetrical IUGR' to allow for such variation. In the digynic fetuses (McFadden/Kalousek Type 2) there were poor growth characteristics with IUGR being more severe and asymmetrical. The diandric fetuses were as common as digynic fetuses in this series. The ratio of diandric to digynic specimens was 11:8 but if only fetal specimens (not embryos or mosaic children) were included the ratio was 6:5. Many diandric conceptions end as partial moles but later in gestation diandric fetuses may be well grown. It is proposed that there may be a survival barrier for diandric fetuses early in gestation (possibly based on the proportion of vascularised placental villi), although once this is passed the diandric fetuses are comparatively more viable and better grown than digynic fetuses. In the XXY triploid fetuses, 5/6 had hypoplastic or ambiguous external genitalia (two were recorded as of female phenotype) as has been reported previously. In these, the gonadal histology was testicular in all the diandrics but in the single digynic XXY case, sex reversal was complete with normal uterus and Fallopian tubes and the gonads were histologically ovaries. Two triploid/diploid mosaics were proven to be due to digyny. The probable cause is delayed incorporation of the second polar body into a blastomere and there was evidence of identical alleles from the same sperm being present in both diploid and triploid cells. In one of these triploid/diploid mosaics in which there was a termination of pregnancy (TOP) after prenatal karyotyping the diploid cell line had trisomy 16 which was not evident in the triploid line. This trisomy was probably of post-zygotic origin and we suggest the fetus was rescued by the prominence of the triploid line.
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PMID:Karyotype, phenotype and parental origin in 19 cases of triploidy. 1174 61

Mosaicism 45X/47XXX is a sporadic form of ovarian dysgenesis. Many of the cases previously described were characterized by a variable phenotype expression. We here report the case of a 33-yr-old woman with recent secondary amenorrhea, weight loss and breast regression. Her menarche had occurred at the age of 11 yr and 6 months and her menstrual cycles had been regular until the age of 28; then, oligomenorrhea and hypertricosis developed. A pelvic ultrasound showed enlarged polycystic-like ovaries and normal uterus. She was treated with ethynil-estradiol and cyproterone acetate for one year. At the age of 31 yr, she underwent a pelvic ultrasound--which revealed normal volume of the ovaries--and hormonal assays including FSH (69 UI/l), LH (113 UI/l), 17beta-estradiol (88 pg/ml), plasma androgens and cortisol levels within normal ranges. No organ-specific autoantibodies toward ovaries, steroid-producing cells or adrenals were found. At the age of 33 yr, there was ultrasound evidence of streak-like ovaries. The patient's height was 145 cm and her weight 45 kg. She had normal female external genitalia, abnormal upper-to-lower body segment ratio, webbed neck, low posterior hair line, cubitus valgus, short and asymmetrical 4th metacarpi, hallux with lateral deviation and moderate scoliosis. No increase in ovarian steroids were found after GnRH-analogue triptorelin (0,1 mg sc) administration. The karyotype analysis on peripheral blood lymphocytes showed a mosaic 45X (90% cells) and 47XXX (10% cells). Diagnostic pelviscopy confirmed streak gonads. Chronic lymphocytic thyroiditis was diagnosed but no cardiovascular or kidney abnormalities were found. A neuro-psychological evaluation revealed emotional and social immaturity, disorders in motorial coordination, visual-spatial organization, as well as reading difficulties and impaired complex phrase construction. The presence of several somatic features of Turner's syndrome, neuro-psychological disorders and an interesting natural history probably depended on the quantitative proportion of 45X to 47XXX cell-lines in different tissues and organs. Estrogen and progestin replacement therapy led to weight gain, re-appearance of secondary sexual characteristics and a mild improvement in mental equilibrium.
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PMID:Turner's syndrome mosaicism 45X/47XXX: an interesting natural history. 1176 52

Artificial insemination with sexed semen, in vitro fertilisation and intracytoplasmic sperm injection have been used to reproduce animals, but often not as successfully as natural mating. Learning more about how spermatozoa normally interact with the female tract can provide inspiration for developing improvements in assisted reproduction. The present review focuses on Bos taurus, because more is known about this species than others. At coitus, bull spermatozoa are deposited into the anterior vagina, where they rapidly enter the cervix. Cervical mucus quickly filters out seminal plasma from spermatozoa, unlike most assisted reproduction protocols. Spermatozoa that reach the uterus may require certain cell surface proteins to swim through the uterotubal junction. Shortly after passing through the junction, most spermatozoa are trapped in a storage reservoir by binding to oviducal epithelium, in the case of cattle via bovine seminal plasma (BSP) proteins coating the sperm head. As ovulation approaches, spermatozoa capacitate and shed BSP proteins. This reduces sperm binding to the epithelium and releases them from storage. Motility hyperactivation assists spermatozoa in leaving the storage reservoir, swimming through oviducal mucus and the cumulus oophorus, and penetrating the oocyte zona pellucida. Chemotactically regulated switching between asymmetrical (i.e. hyperactivated) and symmetrical flagellar beating may also guide spermatozoa to the oocyte.
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PMID:Interactions of spermatozoa with the female reproductive tract: inspiration for assisted reproduction. 1738 39

Genus-specific reproductive processes and strategies displayed by equids, camelids and elephantids are compared and contrasted to illustrate the amazing diversity of reproductive physiology between genera and the equally surprising conservation of reproductive processes across a genus in the face of other dramatic phenotypic modifications and adaptation to prosper in the prevailing environment. From intrauterine conceptus mobility and chorionic gonadotrophic secretion by specialised invasive trophoblast cells in equids, through induced ovulation, an asymmetrical uterus and an almost absurdly short dioestrous interval in camelids, to intrabdominal testes, the testosterone-driven expression of musth and a very tenuous intrauterine attachment of the placenta in elephantids, reproductive physiology remains a discipline of great fascination and academic merit with much yet to be discovered and understood across the whole mammalian kingdom.
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PMID:Sex, science and satisfaction: a heady brew. 2046 95


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