PubMed Health⌕ Search

Biomedical subjects

C Madahar

Publications and source records attributed to C Madahar.

10 recordsLinked to original sources
PubMed1987

Progression in a chemically induced transplantable human pancreas carcinoma.

A methylnitrosourea (MNU)-induced transplantable human pancreas carcinoma was examined, at 3, 12, 18 and 36 months after its development, for growth and invasiveness in nude mice, karyotypic alteration and the evolution of marker chromosomes. Progression in tumorigenicity and invasiveness of cells were evident by a significant increase in tumor diameters produced within 8 weeks by the cells at 36 months as compared to those developed by cells from 3-month-old cell lines. Chromosome analysis at 3 months showed normal 46 XX karyotype in about 80% and minor anomalies in 20% of the cells. At 12, 18 and 36 months, all cells were hyperdiploid with 53-61 chromosomes and several abnormal marker chromosomes. Marker chromosomes showed non-reciprocal translocations, deletions, inversion and isochromosomes. The absence of chromosome 13 from the earlier stage onward may have resulted in the loss of genes which suppress tumorigenicity. The increase in homogeneously staining regions of marker chromosome 3 at later stages appears to parallel the augmentation in tumor growth and mitotic indices.

Animals↗
PubMed1982

Higher incidence of small Y chromosome in humans with trisomy 21 (Down syndrome).

The length of the Y chromosome was measured in 42 black patients with trisomy 21 (47,XY,+21) and a similar number of normal individuals of American black ancestry. The length of the Y was expressed as a function of Y/F ratio and arbitrarily classified into five groups using subjectively defined criteria as follows: very small, small, average, large, and very large. Thirty-eight % of the trisomy 21 patients had small or very small Ys compared to 2.38% of the controls (P less than 0.01). In both populations the size of the Y was not normally distributed. In the normals it was skewed to the left, whereas in the Downs the distribution was flat (platykurtic). A significantly higher incidence of Y length heteromorphisms was noted in the Down as compared to the normal black population. In the light of our current understanding that about one-third of all trisomy 21 patients are due to paternal nondisjunction, it may be tempting to speculate that males with small Y are at an increased risk for nondisjunction of the 21 chromosome.

Adolescent↗
PubMed1980

Temporary increase in chromosome breakage in an infant prenatally exposed to lead.

An infant exposed to high levels of lead in utero was found to have increased numbers of cells with chromosome breaks in blood samples obtained at 6 weeks and 3 months of life. Later samples did not show significant abnormality. Physical and neurological examinations of the patient up to 18 months of age gave results within normal limits.

Adolescent↗
PubMed1980

Distal 18q deletion without clinical findings of 18q- syndrome.

A de nova translocation of long arm of chromosome 3 to the distal third of long arm of 18 was detected in a 10 years old boy, whose phenotype has been somewhat affected. Although the translocation has resulted in loss of distal segment of 18q, clinically he bears little resemblance to 18q- syndrome.

Child↗
PubMed1979

The SC phocomelia syndrome: report of two cases with cytogenetic abnormality.

We report two sibs with the SC phocomelia syndrome with typical facial appearance and bilateral absence or extreme hypoplasia of the fibula, radius, and thumb. One sib had bilateral humero-ulnar and femoro-tibial synostosis (absence of the elbow and knee joints). Application of the nosologic criteria of Herrmann and Opitz showed that there was no significant intrafamilial variation in phenotype. Chromosome analyses in both patients showed heterochromatic puffing and centromere separation involving many chromosomes, an observation that has previously been reported in patients with SC phocomelia and Roberts syndromes. More important, this finding will have significance in prenatal detection of a certain proportion of cases with these syndromes without resorting to the use of radiographic examinations.

Adolescent↗
PubMed1979

Ring chromosome 17 in a mentally retarded boy.

A six-year-old boy was found to have a ring chromosome 17. In addition to psychomotor retardation, speech delay and seizure disorders, his abnormal phenotypic features included epicanthal folds, broad depressed nasal bridge, protruding thick upper and lower lips, micrognathia, narrow high arched palate, short fifth fingers with a mild degree of clinicodactyly, multiple café-aui-lait spots, and abnormal dermatoglyphics.

Abnormalities, Multiple↗
PubMed1977

Trisomy 9 syndrome.

An infant is described with multiple congenital anomalies associated with mosaic trisomy 9. Review of the three previously reported cases of trisomy 9 shows that these patients have several common features which make trisomy 9 a clinically distinct syndrome. The frequently encountered findings are: upward-slanted eyes, small palpebral fissures, enophthalmos or microphthalmos, broad base and prominent tip of the nose, microcephaly, micrognathia, low-set malformed ears, high-arched palate, congenital heart disease, skeletal and genito-urinary anomalies, abnormal palmar creases, failure to thrive, hypotonia and retardation.

Abnormalities, Multiple↗