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Biomedical subjects

I Beck

Publications and source records attributed to I Beck.

At least 19 recordsLinked to original sources
PubMed1991

Enhancer element at the 3'-flanking region controls transcriptional response to hypoxia in the human erythropoietin gene.

Erythropoietin gene expression is greatly stimulated under conditions of hypoxia. The activation of the erythropoietin gene appears regulated primarily at the level of gene transcription. To study cis-acting elements involved in the response to hypoxia a mini-gene was constructed by an internal deletion from exon II to V of the human erythropoietin gene and used in transient transfection assays in the erythropoietin producing Hep 3B cell line. It was initially found that hypoxia responsiveness was present in an erythropoietin fragment containing 400 base pairs (bp) of 5'-flanking and 600 bp of 3'-flanking regions. Deletion analysis showed no significant effect on the response to hypoxia when highly conserved regions of 5'-flanking sequence, exon and intron I, and exon V were removed from the mini-gene construct. However, removal of a fragment containing the 3' end of the gene and 3'-flanking sequences completely eliminated hypoxia responsiveness. Reinsertion of the above fragment upstream of the 5' end of the mini-gene restored the response to hypoxia. Further analysis using hybrid erythropoietin-chloramphenicol-acetyltransferase constructs allowed the localization of enhancer-like element(s) in the 3'-flanking region, approximately 120 bp downstream of the polyadenylation site of the human erythropoietin gene. Activation by these sequences were position- and orientation-independent and stimulated 15-fold transcription of the erythropoietin gene in response to hypoxia.

Cells, Cultured↗
PubMed1990

General practitioner obstetrics in Bradford.

The standard of obstetrics care by general practitioners in Bradford was assessed by reviewing the case records of all women who in 1988 were booked for delivery under their general practitioner but subsequently required transfer to consultant care. A total of 5885 women were delivered in Bradford during 1988. Of 1289 booked under their general practitioner, 637 required transfer to consultant care. In 259 cases transfer occurred during labour; only 37 of these women were visited by their general practitioner. Many of the problems that precipitated transfer were predictable and some were considered preventable: 263 of the women transferred were considered unsuitable for booking by general practitioners. The perinatal mortality among women booked under their general practitioner was 10.1/1000 and the stillbirth rate 7.8/1000. These figures are high and suggest a need for tighter controls over the qualifications and experience of doctors participating in a fully integrated system of obstetric care.

Consultants↗
PubMed1989

Temporary complementation of temperature-sensitive mutants of the cell cycle by transfection with a wild-type or a mutant cDNA of ADP/ATP translocase.

A number of cell-cycle-specific temperature-sensitive (ts) mutants have been isolated from animal cells, especially Syrian hamster cells. These ts mutants, like cell cycle ts mutants of yeast, can be complemented by specific genes, some of which have been molecularly cloned. We have isolated a cDNA clone that complements TK-ts13 cells, but only temporarily. This clone, called B1, differs from a previously isolated clone (Sekiguchi et al.: EMBO Journal 7:1683-1687, 1988) that specifically complements ts13 cells. In addition, B1 also complemented temporarily three other ts mutants of the cell cycle, tsAF8, ts694, and ts550C cells. These mutants have different mutations since, in cell fusion experiments, they complement each other. Sequencing of the B1 cDNA clone revealed that it was a mutant of human ADP/ATP translocase in which some human sequences at the 5' end have been replaced by SV40 sequences. The wild-type translocase was less effective but could still increase the survival time of cell cycle ts mutants at the restrictive temperature. Using the polymerase chain reaction, it was possible to demonstrate that the B1 plasmid is expressed in TK-ts13 cells undergoing temporary complementation.

Amino Acid Sequence↗
PubMed1989

Changes in nuclear distribution of large tumor antigen correlate with the proliferative activity of simian virus 40-transformed cells.

A correlation between intranuclear distribution of large tumor antigen (T-ag) and proliferative activity in Simian virus 40 (SV40)-transformed cells has been established. Nuclear T-ag was cytochemically detected by the immunoperoxidase reaction. Cell populations with a high growth rate displayed a heterogeneous pattern with patches of positive reaction surrounded by large and irregular negative areas. By contrast, cell populations with a low growth rate presented a rather homogeneous distribution of nuclear T-ag with a finely granular positive reaction all over the nucleus, excluding nucleolus-like areas. The latter pattern was also observed in cells that had been inhibited from traversing S phase. In this case, the heterogeneous distribution of T-ag within the nucleus was recovered once the cells were allowed to proceed again through S phase, or through G2 phase. Highly condensed chromatin in mitotic chromosomes appeared to exclude T-ag fully as early as in prophase. Then, nuclear distribution of T-ag changes throughout the cell cycle, thus suggesting it might be a cell cycle-dependent event. Interestingly, thymidine-labeled cells from cultures with a high growth rate presented a heterogeneous distribution of autoradiographic grains. Regardless of their mechanism(s) of origin, T-ag-enriched areas might correspond to nuclear sites where a specific function, such as DNA synthesis, is being carried out.

Animals↗
PubMed1987

Lymphocyte responses in systemic lupus erythematosus in pregnancy.

There is a high incidence of pregnancy loss in patients with systemic lupus erythematosus (SLE). This may be due to clinically undetectable exacerbations of the disease. Two case reports are presented in which the patients' lymphocyte responses were assessed throughout pregnancy. The results obtained suggest that monitoring lymphocyte responses may be a useful indicator of disease activity in pregnancy.

Adult↗
PubMed1985

Ectopic pregnancy in a distal tubal remnant.

Ectopic pregnancy is a well-recognized complication of tubal reanastomosis (Young PE, Egan JE, Barlow JJ: Reconstructive surgery for infertility at the Boston Hospital for Women. Am J Obstet Gynecol 108: 1092, 1970 and Hodari AA, Vibhasiri A, Isaac AY: Reconstructive tubal surgery for midtubal obstruction. Fertil Steril 28: 620, 1977). We describe here, however, a case of tubal pregnancy occurring in a tubal remnant on the opposite side to a successful tubocornual reanastomosis.

Adult↗
PubMed1983

A longitudinal study of leucocyte numbers and mitogenesis during the last ten weeks of human pregnancy.

Leucocyte numbers rose consistently in normal primigravid women sampled repeatedly during the last ten weeks of pregnancy. The increase in total leucocyte count was significant from 35 weeks gestation to delivery and was directly related to an increase in neutrophils, while mononuclear cell numbers remained unaltered. In addition to the pregnancy associated neutrophilia there was a further increase in neutrophil counts at delivery. Using whole blood and purified leucocytes in culture, it was confirmed that pregnancy plasma contains suppressor factors which inhibit mitogenesis with PHA or Con A. There was no significant change in individual women's whole blood mitogenic response at any time during the sampling period except at delivery when there was a significant decrease. Culture of washed cells from pregnant women in non-pregnancy plasma restored their mitogenic response to levels found in non-pregnant control women, except at delivery when there was evidence of a cell-associated impairment of function. Purified leucocyte cultures from individual women sampled repeatedly from 30 weeks gestation to delivery gave variable responses although it was still possible to identify pregnancy-related plasma suppressor factors and delivery-associated impairment of leucocyte function in vitro.

Cells, Cultured↗
PubMed1981

[Yersinioses. Clinical, patho-anatomical and pathogenetic problems (author's transl)].

On the basis of a selected patient group and bioptic material, the difficulties in diagnosing Y. pseudotuberculosis and Y. enterocolitica infections are presented from the clinical and morphological point of view, particularly when extraintestinal complications are present. Taking one patient with Y. enterocolitica infection and recurrent oligoarthritis as an example, the possible pathogenetic significance of circulating immune complexes for the development of extraintestinal symptoms is being discussed.

Adolescent↗