Accessory marker chromosomes are occasionally discovered in normal individuals and they are presumed "clinically inert" since they do not appear to have any phenotypic effect. However, they do pose a theoretical risk at meiosis since they could disrupt the normal pairing and disjunction of homologous chromosomes. Sperm chromosome complements have been studied in two normal males, each of whom carry a small bisatellited accessory marker chromosome 47,XY, + mar (psps), to determine if these marker chromosomes are associated with an increased frequency of aneuploid gametes. Pronuclear chromosomes were visualized after in vitro fertilization of golden hamster eggs with human sperm. The frequency of sperm complements containing a marker chromosome was not significantly different from 50% as theoretically expected, in either male (17/43 and 13/31 with marker chromosomes). One male had 2/43 (4.7%) aneuploid sperm, which is very close to the average frequency of aneuploid sperm seen in control donors (5%). The other male had 6/31 complements with chromosomal abnormalities. One set of sperm chromosomes had structural abnormalities, and five (16.1%) had numerical abnormalities. This frequency of aneuploidy is significantly elevated over the frequency seen in control donors (P = .0002). It is particularly interesting that all the abnormalities involved small chromosomes, as would be expected if the marker chromosome participated in distributive pairing and thereby disrupted normal disjunction of chromosomes of similar size. These preliminary results suggest that accessory marker chromosomes may increase the risk of aneuploid gametes in some individuals.

Adult↗

PubMed1986

Abdominal visceral perforation secondary to electrical injury: case report and review of the literature.

A patient with a vesico-enteric fistula was successfully treated with resection of the small intestine and dome of the bladder and drainage of the intervening abscess. A search of the literature reveals this to be a very unusual complication of high-voltage electrical injury.

Adult↗

PubMed1986

Chromosomal analysis of unfertilized human oocytes.

Unfertilized human oocytes were obtained from women in an in-vitro fertilization programme. The women had a mean age of 29.4 years (range 24-35 years). Chromosomal complements could be analysed in 50 oocytes. Q-banding of the chromosomes facilitated identification of individual chromosomes: 34 oocytes (68%) had the normal haploid chromosomal complement, 14 complements were hypohaploid (28%), 1 complement was hyperhaploid (2%) and 2 had structural abnormalities (4%). (One oocyte had numerical and structural abnormalities). The 16 abnormal oocytes were obtained from 15 different women. A conservative estimate of aneuploidy in this sample is 4%; however, the frequency of aneuploidy may be higher if there is a predisposition to chromosome loss during oogenesis. This study provides information on the largest series of karyotyped unfertilized human oocytes published to date.

Adult↗

PubMed1986

Physician referral service benefits patients, doctors.

Explore the source record for details and available documents.

Community Participation↗

PubMed1986

The problems and payoffs of setting up a rural health clinic.

Explore the source record for details and available documents.

Certificate of Need↗

PubMed1985

A wheat HMW glutenin subunit gene reveals a highly repeated structure.

A wheat genomic library was screened with two synthetic oligonucleotides (24 and 25 bases in length) complementary to a partial cDNA clone encoding a glutenin gene [Thompson et al. (1983) Theor. Appl. Genet. 67, 87-96]. Glutenins are large molecular weight aggregated proteins of grain endosperm, and major determinants of bread making quality of wheat. Of the two clones obtained one was fully characterized. It contained the sequence of the high molecular weight subunit of glutenin. The amino acid sequence derived from the gene sequence reveals a mature protein (817 amino acids) with a highly repeated structure of two different motifs corresponding to the high glutamine (35.7%), glycine (20.1%) and proline (13.1%) content. The gene does not contain an intron, and possesses a typical eukaryotic promoter; the RNA initiation site is 25-30 bases downstream.

Amino Acid Sequence↗

PubMed1985