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1.
Mol Reprod Dev ; 60(2): 270-6, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11553928

ABSTRACT

Bacillus stick insects have proved adequate for studying a wide array of reproductive modes: sexual, parthenogenetic, hybridogenetic, androgenetic. Hybridogenetic strains (B. rossius-grandii) were thought to discard the paternal "grandii" haploset during first meiotic division and keep the "rossius" hemiclone, whereas the clonal B. whitei (=rossius/grandii) would maintain its hybrid structure by fusing back two nonsister nuclei-each derived from previously segregated heterospecific complements-by the end of the 2(nd) meiotic division. New investigations on laid eggs and ovariole squashes, either DAPI stained or FISH labeled, revealed that in hybridogens the "grandii" set is excluded from the germ line prior to meiosis and that a DNA extra-synthesis should occur to produce hemiclonal eggs after two cytologically normal meiotic divisions. On the other hand, in B. whitei eggs no genome segregation appears to occur and an intrameiotic DNA extra-synthesis must take place to produce 2n tetrachromatidic oocytes I; these divide twice and give unreduced clonal eggs. The new findings bring hybridogenetic oogenesis of Bacillus to be coincident with that of the known hemiclonal organisms and point to an independent onset of B. whitei from hemiclonal strains. In addition, B. whitei gains a closer resemblance to B. lynceorum owing to the sharing of a cytologically identical egg maturation mechanism, of the same maternal ancestor and of peculiar chromosomal features. It is here suggested that B. lynceorum originated from the incorporation of an "atticus" genome into a B. whitei egg, according to a pathway of repeated hybridization often occurred with other polyploid hybrids.


Subject(s)
Fluorescent Dyes/metabolism , In Situ Hybridization, Fluorescence , Indoles/metabolism , Insecta/physiology , Meiosis/physiology , Oocytes/growth & development , Animals , Female , Histocytological Preparation Techniques , In Situ Hybridization , Insecta/genetics , Male , Meiosis/genetics , Oocytes/cytology , Parthenogenesis/genetics , Sexual Behavior/physiology
2.
J Clin Endocrinol Metab ; 84(4): 1304-10, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10199771

ABSTRACT

Sixty-six hirsute women were randomized and treated with 1) flutamide (n = 15), 250 mg/day; 2) finasteride (n = 15), 5 mg/day; 3) ketoconazole (n = 16), 300 mg/day; and 4) ethinyl estradiol (EE)-cyproterone acetate (CPA; n = 20), 0.01 mg EE/day for the first week, 0.02 mg EE/day for the second week, and 0.01 mg EE/day for the third week, followed by a pause of 7 days, then 12.5 mg CPA/day added during the first 10 days of every month for 12 months. Hirsutism was evaluated by the Ferriman-Gallwey score, and hair diameter and hair growth rate were determined by a special image analysis processor in basal conditions and after 90, 180, 270, and 360 days of treatment. All treatments produced a significant decrease in the hirsutism score, hair diameter, and daily hair growth rate: flutamide, -55 +/- 13%, -21 +/- 14%, and -37 +/- 18%; finasteride, -44 +/- 13%, -16 +/- 12%, and -27 +/- 14%; ketoconazole, -53 +/- 18%, -14 +/- 12%, and -30 +/- 21%; and EE-CPA, -60 +/- 18%, -20 +/- 11%, and -28 +/- 21%. Some differences existed among treatments with regard to effectiveness; EE-CPA and flutamide seem to be the most efficacious in improving hirsutism. For the hirsutism score, a greater decrease was seen with EE-CPA (-60 +/- 18%) than with finasteride (-44 +/- 13%; P < 0.01) and a greater decrease was seen with flutamide (-58 +/- 18%) than with finasteride (-44 +/- 13%; P < 0.05). Flutamide is the fastest in decreasing hair diameter; EE-CPA is the fastest in slowing down hair growth, even though at the end of the treatment there was a significant difference between flutamide and finasteride only (-41 +/- 18% vs. -27 +/- 14%; P < 0.05). Flutamide, ketoconazole, and EE-CPA induced a significant decrease in total and free testosterone, 5alpha-dihydrotestosterone, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione plasma levels. During the EE-CPA treatment, gonadotropins were suppressed, and the sex hormone-binding globulin level increased. Finasteride induced a decrease in dehydroepiandrosterone sulfate and 5alpha-dihydrotestosterone and an increase in testosterone levels. Very few side-effects were observed during treatment with low doses of flutamide, EE-CPA, and particularly finasteride. Flutamide induced a decrease whereas EE-CPA induced an increase in triglycerides and cholesterol, showing higher values within the normal range. Ketoconazole induced several side-effects and complications, and several people dropped out of the study. Despite different modalities of action and significantly different effects on androgen levels, low doses of flutamide, finasteride, and EE-CPA constitute very satisfactory alternative therapeutic regimens in the treatment of hirsutism.


Subject(s)
Cyproterone Acetate/administration & dosage , Ethinyl Estradiol/administration & dosage , Finasteride/therapeutic use , Flutamide/therapeutic use , Hirsutism/drug therapy , Ketoconazole/therapeutic use , Adult , Cyproterone Acetate/adverse effects , Ethinyl Estradiol/adverse effects , Female , Finasteride/adverse effects , Flutamide/adverse effects , Hormones/blood , Humans , Ketoconazole/adverse effects , Prospective Studies
3.
Genome ; 40(2): 261-70, 1997 Apr.
Article in English | MEDLINE | ID: mdl-18464826

ABSTRACT

Bacillus atticus atticus is a complex of thelytokous parthenogens, related to the bisexual Bacillus grandii, that ranges from Sardinia to Near Eastern countries. Karyotypic and cytogenetic differentiation of the B. atticus atticus diploid unisexual "isolates" is really higher than expected. Its standard karyotype has 2n = 34 chromosomes, but several instances of repatterned or even aneuploid complements have been found. The number and location of silver-stained NORs are particularly intriguing, since in addition to homozygous NOR patterns, simple or double hemizygous strains are found spread over specific and wide regions. The odd patterns are not due to Ag-NOR staining technique artifacts, since the FISH method, using rDNA probes, apparently labels the same ribosomal clusters. Transpositions and translocations have been suggested to account for some NOR patterns, but hybridizations between different NOR-bearing races are also a possible cause. This chromosomal survey clearly contributes to a better understanding of B. atticus phylogeny.

4.
Genome ; 36(2): 317-26, 1993 Apr.
Article in English | MEDLINE | ID: mdl-18469990

ABSTRACT

The standard karyotype and a wide array of repatterned cytotypes from 21 demes of the double-allotriploid thelytokous Bacillus lynceorum have been analyzed by means of Giemsa, C-banding, and silver-staining techniques. The present study substantially amends the first karyotype description and also analyzes in detail the chromosomal rearrangements to trace their most likely derivation. Bacillus lynceorum cytotypes also provide a well-documented instance of an intraspecific gain of centromeric function. The contribution of three different specific haplosets is particularly evidenced from centromeric heterochromatin pattern and satellite/Ag-NOR locations. In stick insects, both hybridogenetic and parthenogenetic Bacillus hybrids, including B. lynceorum, can utilize the rDNA of all available parental haplosets, although a hierarchical role of the B. rossius genome seems to emerge. Satellite/Ag-NOR patterns, besides clearly allowing the recognition of ancestral parental genomes, also suggest a polyphyletic origin for B. lynceorum, which, to our knowledge, represents the only described karyotype of a trihybrid invertebrate.

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