PubMed Health⌕ Search

Biomedical subjects

S Borgmann

Publications and source records attributed to S Borgmann.

26 records · Page 2Linked to original sources
PubMed1997

Conserved Y-chromosomal location of TSPY in Bovidae.

We determined the chromosomal location of TSPY, the testis-specific protein, Y-encoded, by fluorescence in situ hybridization (FISH) to chromosome spreads of cattle, goat and sheep. Using a cloned polymerase chain reaction (PCR) product of one bovine TSPY family member, we were able to show a conserved Y chromosomal localization for TSPY in all three species. In contrast to a limited regional distribution of TSPY FISH signals on the chromosome of man, other primates, great apes, goat and sheep, in cattle TSPY-related sequences appear to be spread over most of the Y chromosome. The painting effect observed in this species reflects the higher complexity of the bovine TSPY gene family, being composed not only of a tandemly repeated cluster, but harbouring a large number of different family members dispersed all over the Y chromosome.

Animals↗
PubMed1996

Sex reversal in a child with the karyotype 46,XY, dup (1) (p22.3p32.3).

The karyotype 46,XY, dup(1) (p22.3p32.3) was found in a 10-year-old patient with sex reversal, mental retardation and multiple dysmorphic features. In other cases with duplication 1p but different breakpoints cryptorchidism and genital ambiguity have been observed suggesting the dosage effect of a locus in 1p involved in sex differentiation.

Abnormalities, Multiple↗
PubMed1994

Electron microprobe analysis of electrolytes in whole cultured epithelial cells.

Microprobe analysis was used to determine electrolyte contents in whole epithelial sheets of A6 cells and to investigate the most critical points of this method. Analysis of dextran standard sections of different thickness revealed that low accelerating voltages of about 10 kV are best suited for whole freeze-dried cells on thick supports, since 5 microM thick sections are not penetrated by 10 kV electrons. Washing of A6 cells for 10 sec with distilled water led to cell swelling of about 40%, but the molar concentration ratios and the concentrations per dry weight (dw) were not altered. Washing for 60 sec with distilled water caused a further increase in cell volume (120%) and loss of cellular K and Cl (90 mmol/kg dw). Washing with isotonic NH4- acetate led to a loss of cell Cl already after 10 sec. To characterize the Na transport compartment, A6 cells cultured on permeable supports were washed for 5 sec with distilled water, freeze-dried, and analyzed. Inhibition of transepithelial Na transport by ouabain increased Na/P from 0.15 +/- 0.07 to 0.75 +/- 0.03 and Cl/P from 0.21 +/- 0.001 to 0.38 +/- 0.003 while K/P decreased from 0.83 +/- 0.08 to 0.32 +/- 0.03. The changes in cell Na and K contents can be explained by K/Na exchange; the increase in Cl content indicates some cell swelling. Since the ouabain-induced changes could be prevented by apical amiloride, the apical membrane provides the most important pathway for Na entry in A6 cells.

Animals↗
PubMed1993

A natural rubber drainage tube with antithrombogenic lumen surface.

A drainage tube was made by radiation vulcanization of a high polymeric substance based on natural rubber elastomers. Pentosan polysulphate sodium bound to a carrier substance (synthetic type 4A or 13X zeolite) was incorporated in the drainage tube which was then tested for its anticoagulant properties during perfusion with Tris buffer solution, citrated plasma, and blood, resp. The amount of pentosan polysulphate sodium released from the tube walls during perfusion with human citrated plasma in an open circulatory system was sufficient to exert an anticoagulant effect on the streaming plasma. This effect was corroborated by prolonged thrombin times and by unclottability in case of recalcified plasma samples in thrombelastographic studies. The antithrombogenicity test according to Chandler in a closed circulatory system revealed thrombus formation times (TFT) of more than 24 h (control: TFT = 1-3 min in native blood).

Animals↗
PubMed1990

Cytogenetic analysis of 750 spontaneous abortions with the direct-preparation method of chorionic villi and its implications for studying genetic causes of pregnancy wastage.

Altogether, 750 cases of spontaneous abortion between the fifth and 25th week of gestation were analyzed cytogenetically by the direct-preparation method using chorionic villi. The majority of cases (68%) were derived from early abortions before the 12th week of gestation. The frequency of abnormal karyotypes was 50.1%; trisomy was predominant (62.1%), followed by triploidy (12.4%), monosomy X (10.5%), tetraploidy (9.2%), and structural chromosome anomalies (4.7%). Among trisomies, chromosomes 16 (21.8%), 22 (17.9%), and 21 (10.0%) were prevalent. The frequency of chromosomally abnormal abortions increased with maternal age but only because of an increase of trisomy. Polyploidy and monosomy X, however, decreased. Mean maternal age was significantly increased for trisomies 16, 21, and 22 and was highest for trisomies 18 and 20. The results obtained are within the range of variability reported earlier from tissue culture-type studies. A consistent feature during our study is the excess of females in chromosomally normal abortions (male:female sex ratio 0.71). According to the methodology applied, maternal cell contamination and undetected 46,XX molar samples cannot have influenced the sex ratio. However, a bias introduced by social status or maternal age cannot be excluded. With the more rapid and convenient direct preparation of chorionic villi, reliable cytogenetic data on causes of spontaneous abortions can be obtained.

Abortion, Spontaneous↗
PubMed1988

Studies on elastomeric materials with incorporated antithrombotics.

Antithrombotically effective drugs (heparin, pentosan polysulphate, streptokinase) were incorporated into elastomeric materials by means of zeolites as carrier. The incorporated antithrombotic agents can be delivered to the surrounding medium. These self-antithrombotic elastomers may be used as tubes to drain off body fluids (catheters, drains, etc.).

Adsorption↗
PubMed1987

A cytogenetic study directly from chorionic villi of 140 spontaneous abortions.

Spontaneous abortions were studied by analyzing chromosomes directly from chorionic villi. The frequency and the type of anomalies detected among 140 abortuses are in good agreement with those observed by others using conventional tissue cultures. Abnormal karyotypes were found in 48.6% of the cases. Trisomy predominated (66.2%), followed by polyploidy (22.1%), monosomy X (7.4%), and structural anomalies (4.4%). Among the trisomies, the most prevalent were of chromosome 22 (22.2%), 16 (22.2%), and 13 (9.5%). The relative frequencies of trisomies, monosomy X, and the different chromosomes involved in trisomies seem to differ between our study and those in which tissue cultures were analyzed. Our low frequency of 45,XO karyotypes and the shift to trisomies of chromosomes whose involvement increases steeply with maternal age are considered due to the approximately 3 year higher mean maternal age in our sample. The sex ratio (male to female) in chromosomally abnormal abortuses was 1.28, which is nearly identical to the 1.2 found in earlier studies. Surprisingly, in chromosomally normal abortions males were significantly outnumbered by females (sex ratio 0.76). Since maternal cell contamination cannot have influenced the sex ratio in our study, we consider it worthwhile to investigate whether failures associated with X inactivation are responsible for pregnancy wastage of some euploid female conceptuses. Knowledge of the karyotypes may serve as a prerequisite for the investigation of non-chromosomal genetic causes of pregnancy wastage.

Abortion, Spontaneous↗