Search PubMed⌕ Search

Biomedical subjects

M Bobrow

Publications and source records attributed to M Bobrow.

At least 163 records · Page 9Linked to original sources
PubMed1985

Two cases of X/autosome translocation in females with incontinentia pigmenti.

We report two unrelated girls who present some clinical features of severe incontinentia pigmenti (IP), with characteristic skin pigmentation. Both have balanced de novo X/autosome translocations involving band Xp11. The coincidence of the probable de novo expression of an X-linked disorder in these two girls with translocations involving similar breakpoints on the X chromosome suggests that this band may be the site of the IP gene locus.

Child, Preschool↗
PubMed1985

Heterochromatic chromosome variation and reproductive failure.

The literature on the association of heterochromatic chromosome variants and reproductive failure, manifesting as infertility or recurrent spontaneous abortion, is critically reviewed. Many methodological problems confound attempts to interpret the data. The weight of evidence is against autosomal variants having any significant effect. Although conflicting, reports on the effect of Y heterochromatin variants on both infertility (Yq-) and recurrent abortion (Yq+) are mainly positive, and further data are required in both these areas.

Abortion, Habitual↗
PubMed1984

Familial occurrence of azoospermia and extreme oligozoospermia.

To determine the familial incidence of azoospermia and extreme oligozoospermia (AEO; sperm counts less than 3.10(6)/ml) 147 men with primary AEO were asked, by means of mailed questionnaires, for the occurrence of infertility among their brothers. 119 questionnaires were completed (81%). Out of a total of 163 informative brothers 7 were reported infertile, of whom 3 had a documented AEO. This incidence is probably about double the general population frequency. A familial case of congenital aplasia of the vasa deferentia was found; this has previously been reported to recur in a sibship and may represent a simple inherited disorder.

Adult↗
PubMed1984

Paracentric inversions in man.

We have reviewed 50 cases of paracentric inversions. Of these 34 were familial with 62 phenotypically normal carrier relatives. Twenty of the 50 were discovered fortuitously. There were two reports of children with easily recognised unbalanced karyotypes resulting from a paracentric inversion in one of the parents. The vast majority of paracentric inversions are harmless. The risk of abnormal children for paracentric inversion heterozygotes is low but increases with the finding of recurrent abortions or abnormal children or both in other carriers in the family. We emphasise the need for caution in interpreting the results of antenatal diagnosis because of the variety of unexpected unbalanced chromosome types that can result from a paracentric inversion, and the difficulty in recognising, with confidence, minute differences (for the detection of which very high resolution banding is required) between apparently similar parental and fetal inversions.

Abortion, Habitual↗
PubMed1984

Hospital safeguards capital program through private sector partnership.

As access to capital tightens, more hospitals are exploring the benefits of partnerships with private companies. A California hospital, burdened by the long-term debt it incurred for a medical office building, worked together with its medical staff and an outside real estate developer. By selling the building to the developer, not only was the hospital able to finance a much-needed expansion and reconstruction project, but the hospital's medical staff had an opportunity to become limited partners in the ownership of the building.

California↗
PubMed1983

Gonadotropins and gonadal steroids in androgen insensitivity (testicular feminization) syndrome: effects of castration and sex steroid administration.

Gonadotropin control mechanisms were examined in 12 subjects with the complete syndrome of androgen insensitivity (testicular feminization). This study confirmed the presence of elevated luteinizing hormone (LH) and normal follicle-stimulating hormone (FSH) values in these subjects and suggests an intact feedback mechanism for FSH but not LH. This gives further credence to the opinion that estrogens and a nonsteroidal inhibin are important in FSH control. Because of an exaggerated pulsatile pattern of gonadotropins in intact and gonadectomized subjects, there were dramatic variations in gonadotropin levels. After gonadectomy, there was a marked rise in FSH and a further rise in LH. Administered estradiol benzoate and, to a lesser degree, testosterone propionate were capable of lowering LH levels. The effect of testosterone could be via conversion to estrogen(s) in the testes or elsewhere.

Adolescent↗
PubMed1983

Nucleoli, micronucleoli, and nucleolus-like structures in human oocytes at meiotic prophase I studied by the silver-NOR technique.

Meiotic nuclei preparations obtained from human fetal ovaries were studied with the silver-NOR technique. At leptotene, the NOR's were located at the periphery of the nucleoli. The mean number of NOR's per nucleus was 6.4. Moreover, 2-12 micronucleoli, each containing an Ag-positive zone, were observed. At pachytene, each nucleolus was divided into two zones, one of which was Ag-positive. The mean number of Ag-positive zones was 2.1 per nucleus. The subterminal region of the short arm of nucleolar bivalents was in contact with the argyrophilic nucleolar zone. In most cells, micronucleoli were dispersed between the bivalents. A single rounded body which stained heavily with silver was consistently observed. At early diplotene, the NOR's separated, appearing again as distinct rounded Ag-positive structures embedded in the peripheral part of the nucleoli. The silver-stained round body was still visible. Eight to twelve micronucleoli were observed. At a more advanced stage of diplotene, the number of micronucleoli increased, varying from 20 to 50 per nucleus. These observations suggest that the micronucleoli, already visible at the leptotene stage, are the morphological expression of an early transcription of amplified rDNA. The biological significance of the Ag-positive round body remains obscure, but the consistency of its appearance suggests that it has a specific function somehow related to nucleolar proteins.

Cell Nucleolus↗
PubMed1982

Carcinoembryonic antigen (CEA) expression in somatic cell hybrids.

Five hybrids (LSB) were formed between LS174T, a human CEA-producing colonic tumor cell line, and BU25.CAPr, a HeLa derivative which does not produce CEA. All five hybrids produce CEA, but less per cell than LS174T. Approximately 10% of the chromosomes have been lost from these hybrids. In an attempt to map the gene(s) coding for the protein moiety of CEA, 7 LSPG and 28 LSR hybrids were formed between LS174T and PG19, an mouse melanoma cell line, and LS174T and RAG, a mouse kidney adenocarcinoma cell line, respectively. These hybrids retain between 4 and 21 human chromosomes, and each human chromosome is represented in at least seven hybrids. Two hybrids appeared to produce trace amounts of CEA. These results might represent repression by the mouse genome of CEA production or the production of a structurally abnormal CEA molecule.

Carcinoembryonic Antigen↗
PubMed1981

Steroid sulphatase levels in XX males, including observations on two affected cousins.

Quantitative assays of steroid sulphatase in XX males have shown that some individuals have two functional loci, and others only one. Two affected cousins, who cannot share the same X-chromosome, nevertheless have male levels of steroid sulphatase, suggesting functional abnormality of the X chromosome. The hypothesis is advanced that these and other unusual features of X-chromosome function in some XX males, could be explained if such cases were due to an autosomal mutation, exercising its effect by causing abnormal inactivation of a subterminal area of Xp which normally escapes the inactivation process.

Arylsulfatases↗
PubMed1980

Nonrandom segregation of nucleolar organizing chromosomes at mitosis?

The random assortment of non-homologous chromosomes at meiosis is one of the fundamental tenets of genetics, to which few exceptions have been documented. The segregation of mitotic chromatids is believed to be similarly random. We report here that we seem to have discovered a new exception to this rule, in that nucleolar organizing chromosomes remain associated with one another, held in the same lateral orientation, for several mitotic cycles.

Cell Nucleolus↗
PubMed1980

Assignment to chromosome 16 of a gene necessary for the expression of human mitochondrial glutamate oxaloacetate transaminase (aspartate aminotransferase) (E.C. 2.6.1.1.).

A gene necessary for the expression of human mitochondrial glutamate oxaloacetate transaminase (GOT-2) has been assigned to chromosome 16 on the basis of an immunochemical analysis of human-mouse somatic cell hybrids. Mitochondrial GOT cosegregates with adenine phosphoribosyl transferase (E.C. 2.4.2.7.).

Adenine Phosphoribosyltransferase↗
PubMed1980

Assignment of the human locus determining phosphoglycolate phosphatase (PGP) to chromosome 16.

The segregation of human phosphoglycolate phosphatase has been studied in 52 independent human-rodent hybrids and 69 subclones. The results suggest that human PGP is on chromosome 16. Family data suggest that PGP is not close to 16qh or alpha Hp. The most likely regional assignment for PGP would appear to be 16p13 or 16p12, but a site on 16q cannot be entirely excluded. New data on 16qh and alpha Hp suggest that the male recombination fraction between these loci is about 0.2.

Alleles↗