Human oviductal cells produces three glycoprotein fractions that stimulate mouse embryo development

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Congenital myopathies: characteristic and subtypes in Hong Kong

This journal suppl. entitled: 20th International Congress of The World Muscle SocietyCongenital myopathies are a group of childhood onset neuromuscular disorder with the diagnosis mainly based on genetic and pathological features. This is a unique group with phenotypic, genotypic and pathological heterogeneity, so the confirmation of an underlying diagnosis is often challenging. This is the first congenital myopathy case series in Hong Kong. A total of 15 patients have been diagnosed to have congenital myopathies with 11 patients had the genetic mutations being identified (4 patients had RYR1 mutations, 3 patients had ACTA1 mutations, 2 patients had KLHL40 mutations, 1 patient had MTM1 mutation and 1 patient had DNM2 mutation).postprin

Cytogenetic and histological studies of the brook trout, Salvelinus fontinalis (Mitchill), and the Arctic char, S-alpinus (L.) hybrids

Although brook trout and the Arctic char hybrids are able to reproduce, individuals with decreased fertility or even fish that are unable to produce any gametes have been also described. Abnormal gonadal development and disturbances in the gamete production in the char hybrid offspring may be triggered by the odd chromosome number and disturbances in their pairing during meiosis. To verify this hypothesis, cytogenetic examination and the gonadal histology analysis of the brook trout x Arctic char hybrids were carried out. Diploid chromosome number in the studied char (F-1) hybrids varied from 82 to 84 (FN = 99-102). Among 28 hybrids, 12 males, three females, nine intersex individuals and two sterile specimens were described. In the case of two individuals, gonads were not found. Diploid chromosome numbers in the males and intersex individuals varied from 82 to 84. Chromosome numbers in the females were 82 and 83 chromosomes. Two sterile fish exhibited karyotypes composed of 82 and 84 chromosomes. Predominance of the ovarian component in the intersex gonads and gonadal sex ratio distortion towards the males suggested hybrid females had problems with gonadal differentiation. However, the lack of the clear relationship between chromosome number and gonadal development in the studied hybrids did not support our hypothesis that odd chromosome number may be responsible for such reproductive disturbances in the hybrid individuals. We have presumed that sterility and intersexual development of the gonads may be caused by interactions between brook trout and Arctic char genes on the sex chromosomes and autosomes rather than unpairing of the parental chromosomes.Polish National Science Center (NCN) [N N311 525240]info:eu-repo/semantics/publishedVersio

A study on the thyroid gland and the TSH cells in the pituitary of the ricefield eel, Monopterus albus

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A cytological study on the structure of the pituitary gland of Monopterus albus (Zuiew)

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Sex steroids in intersexual fishes

Studies of the in vitro gonadal steroidogenesis in intersexual fishes, using labelled testosterone as precursor, showed large species variation. The protogynous Monopterus albus produced predominantly 5α-reduced metabolites while the protandrous Rhabdosargus sarba produced mainly 5β-reduced products. Both fishes synthesized 11-oxotestosterone; the synthesis of which appeared to mediate mainly through adrenosterone in M. albus but via 11β-hydroxytestosterone in R. sarba. When the plasma levels of androstenedione, testosterone, 11-oxotestosterone, 11β-hydroxytestosterone, estrone and 17β-estradiol among the male, intersexual and female phase of the same species were compared, available data showed that either there was no obvious difference among the different sexual phases or the differences could be accounted for by the seasonal reproductive activities of the animal. Except for androstenedione, there are no marked changes in plasma testosterone, 11-oxotestosterone, 11β-hydroxytestosterone, estrone and 17β-estradiol levels in the intersexual phase compared with the female and male, it is unlikely that these classical sex steroids act as a primary trigger of natural sex reversal in these fishes; the role of androstenedione awaits further elucidation. © 1989 Kugler Publications.link_to_subscribed_fulltex

A new method for the simultaneous determination of androstenedione, testosterone, 11-oxotestosterone and 11β-OH-testosterone in fish plasma using combined techniques of celite chromatography and radioimmunoassay

A new method for the simultaneous determination of androstenedione, testosterone, 11-oxotestosterone and 11β-hydroxy-testosterone in teleost plasma has been developed. Steroids extracted from the plasma were first separated by Celite chromatography using ethanediol as the stationary phase and different concentrations of ethyl acetate in iso-octane as the eluting solvents. Androstenedione, testosterone, 11-oxotestosterone and 11β-OH-testosterone were eluted successively with 0, 10, 15 and 40% of ethyl acetate in iso-octane. The eluted steroid fractions were then quantitatively determined by radioimmunoassay. Data on the accuracy, precision, and sensitivity were presented showing that this new assay system was precise and reproducible. As an illustration of its application, this method was used in the present study to determine the plasma androgen levels in Monopterus albus and in methyl-testosterone treated Tilapia mossambicus.link_to_subscribed_fulltex

The in vitro metabolism of radioactive progesterone and testosterone by the gonads of the protandrous Rhabdosargus sarba at various sexual phases

The in vitro steroidogenic capacity of the gonadal tissue in the protandrous Rhabdosargus sarba was studied. Testicular and ovarian tissues from various sexual phases were used either separately or combined. With progesterone as precursor, high yield of 5β-reduced metabolites, and no 11-ketotestosterone or 11β-hydroxytestosterone were found. The production of 5β-pregnan-3α-ol-20-one and 5β-pregnane-3,20-dione was very high in incubations with testicular tissue from intersexes or males and was low in those with ovarian tissue only. The production of 17α-hydroxyprogesterone was high in the female but was low in other sexual phases. With testosterone as precursor, 11-ketotestosterone and 11β-hydroxytestosterone were identified. The latter was the most abundant and prominent polar steroid in all incubations. 5β-Reductase activity was high in the male and relatively low in the female. 5α-Reduced products, however, were absent. There was an increase in the production of androstenedione as the animal underwent sex reversal. The significance of this change in steroidogenesis in this protandrous fish is at present under investigation. Experimental results also indicated that in the intersexual gonad there may be interaction between the testicular component and the ovarian component in steroidgenesis.link_to_subscribed_fulltex

4 Sex Control and Sex Reversal in Fish Under Natural Conditions

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The plasma sex steroid profiles in the freshwater, sex-reversing teleost fish, Monopterus albus (Zuiew)

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