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Biomedical subjects

P Goetz

Publications and source records attributed to P Goetz.

At least 55 records · Page 3Linked to original sources
PubMed1984

On the nature and extent of XY pairing at meiotic prophase in man.

Evidence is presented that pairing between the human X and Y chromosomes could be more extensive at early pachytene than has previously been supposed and could involve even the entire euchromatic portion of the Y chromosome. Following desynapsis over the major part of the X and Y axes, a small paired segment of Xp and Yp remains into late pachytene. Association between the distal tips of Xq and Yq can also be observed in about one half of the spermatocytes examined. A hypothesis linking meiotic pairing to early replicating sites along the chromosomes is proposed.

Adult↗
PubMed1984

Morphological and temporal sequence of meiotic prophase development at puberty in the male mouse.

The correct sequence of meiotic prophase development in the male mouse has been established by the use of pubertal males. The first wave of spermatogenesis at this time provides a unique opportunity to study progressive meiotic development in a direct way. Air-dried and micro-spread analyses have been carried out. Temporal and morphological progression at this time is entirely consistent with that occurring in the later waves of meiosis of the adult male. Morphological detail shows delayed pairing of the X and Y chromosomes relative to the autosomes. The longest XY synaptonemal complex is seen in early pachytene cells, occupying up to 72% of the length of the Y and 22% of the length of the X axis. By late pachytene, end-to-end pairing in the XY bivalent is established, the autosomal axes remaining fully paired. Desynapsis of the autosomes commences at early diplotene. A 'diffuse' diplotene stage in the male, comparable to the dictyate stage of the female, could not be found. Marked lengthening of the XY and autosomal axes did, however, occur through the diplotene stage.

Animals↗
PubMed1981

XY pair associates with the synaptonemal complex of autosomal male-sterile translocations in pachytene spermatocytes of the mouse (Mus musculus).

Analysis of the chromosome behaviour at pachytene has been performed by means of the silver staining technique visualizing the synaptonemal complexes (SCs) in male mice heterozygous for the male-sterile translocations T(5;12)31Hm T(16;17)43H and T(7;19)145H, respectively. the T(9;17)138Ca male heterozygotes and T43H/T43H homozygous males were used as fertile controls. The sterile mice displayed a high frequency (about 60%) of pachytene spermatocytes with autosomal translocation configuration located in close vicinity of the XY pair. The dense round body (XAB), normally located near the X-chromosome axis in fertile males, exhibited abnormal affinity to translocation configuration in the sterile translocation heterozygotes. The incomplete synapsis of autosomes involved in translocation configuration was observed in more than 70% of the pachytene spermatocytes with the male-sterile translocations but less than 20% of the cells from T138Ca fertile male.s. A hypothesis relating the spermatogenic arrest of carriers of male-sterile rearrangements to the presumed interference with X chromosome inactivation in male meiosis is discussed.

Animals↗
PubMed1981

Cytogenetic analysis of translocations induced by the chemical mutagen thio TEPA in spermatids of male mice.

Cytogenetic analysis of meiotic cells at diakinesis/metaphase I was carried out in 36 reciprocal translocation heterozygotes. Translocations were induced in late spermatids of C57BL/6 male mice with 1:25 mg/kg body weight of thioTEPA. The prevalent types of multivalent configuration were Ring IV in 15F1 males, chain IV in 20 males, and one male showed the same proportion of cells with chains and rings. The conclusion can be made that an intensive mutation process with may induce as much as 30% heterozygous translocation males in characterized by a random distribution of breaks along the chromosome.

Animals↗
PubMed1981

Clastogenicity and sister chromatid exchange induction by ftorafur.

The main effect of Ftorafur at the chromosomal level is the induction of chromatid and chromosome breaks, which is some pronounced in neoplastic or transformed cells than in normal cells. Different cell lines used in the study exhibited both in vitro and in vivo varying sensitivity to Ftorafur. Ftorafur does not increase the frequency of SCE.

Animals↗
PubMed1980

Cyclophosphamide-induced chromosomal aberrations in meiotic cells of male mice.

Single doses of 40, 80 and 160 mg of cyclophosphamide per kg body weight were administered intraperitoneally to C57BL/6 male mice. Cytogenetic analysis of spermatocytes at diakinesis/metaphase I, influenced as spermatogonia A and B and pachytene spermatocytes, showed the chromosomal damage. Cyclophosphamide induced structural chromosomal aberrations including translocations and interfered with the normal development of bivalents. The dose of 80 mg/kg yielded 0.6% spermatocytes with translocations and 3% translocation carriers in F1 males. Robertsonian translocations were detected in 3 males.

Animals↗
PubMed1979

Synaptonemal complexes of mouse and human pachytene chromosomes visualized by silver staining in air-dried preparations.

A new method is described which allows light microscopy visualization of the synaptonemal complexes in primary spermatocytes. The conventional acetic acid-alcohol fixed and air-dried preparations can be used for the modified silver staining technique. Several hundred pachytene spermatocytes from a single mouse testis or human testicular biopsy can be examined. The prospective utilization of the present method is briefly discussed.

Animals↗
PubMed1979

Effects of alkylating agents on lymphocytes from controls and from patients with Fanconi's anemia. Studies of sister chromatid exchanges, chromosome aberrations, and kinetics of cell division.

The frequency of sister chromatid exchanges (SCE) and chromosome aberrations and the dynamics of cell division in peripheral blood lymphocytes of four patients with Fanconi's anemia were studied after in vitro exposure to alkylating agents TEPA and mitomycin. SCE frequency was significantly increased even after very low doses of mutagens, while chromosome aberrations were significantly increased only after high doses (0.160 micrograms/ml mitomycin and 10(-5) M TEPA). The responses of Fanconi's anemia cells and control cells did not differ significantly. The increased frequency of both SCE and chromosome aberrations was accompanied by gradual delay of cell division, which was most conspicuous in cells from patients with Fanconi's anemia.

Anemia, Aplastic↗
PubMed1979

[Edwards' syndrome].

Two cases of Edwards' syndrome were observed. One occurred in a girl aged 6 months, the other in a male neonate. The two children showed a highly characteristic appearance of both the face and the extremities, so that it arouse suspicion of 18-chromosomy. The latter was confirmed by a postmortem cytogenetic examination. The syndrome also includes malformations of inner organs and microscopical architectural changes of organs, which occurred in both the cases described, but different in type.

Abnormalities, Multiple↗