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Biomedical subjects

O Mutchinick

Publications and source records attributed to O Mutchinick.

At least 37 records · Page 2Linked to original sources
PubMed1990

Human lymphocyte proliferation kinetics in Hanks' BSS supplemented with autologous plasma and in synthetic medium.

Human lymphocyte proliferation kinetics was studied in different culture conditions including synthetic medium, Hanks' BSS and Hanks' supplemented with autologous plasma at several culture times. Even though mitotic indices (MI) were low, lymphocytes were able to divide for a few cycles in BSS alone, with a cycling time of around 24 h. Similar cell proliferation patterns with similar MIs, replication indices and cell cycle times of approximately 12 h were obtained with RPMI 1640 and with autologous plasma-supplemented BSS, although lymphocytes exhibited a more uniform MI distribution curve in synthetic medium. The findings mentioned above suggest that Hanks' with autologous plasma may represent a suitable and inexpensive culture condition to avoid undesirable side effects related to synthetic media and heterologous sera, for diagnostics as well as research cytogenetics.

Acetates↗
PubMed1988

Duplication 11q and deletion 5p syndromes due to a reciprocal translocation segregating in four generations.

We report on 2 relatives with duplication 11q and deletion 5p, resulting from an adjacent-1 segregation of a balanced reciprocal translocation 5p15;11q23, segregating in 4 generations of this family. Twelve out of 16 at-risk relatives of inheriting the translocation were shown to be carriers, giving a significant (p less than .05) 3:1 ratio of carriers/noncarriers. The breakpoint on chromosome 11 at q23 is a folate sensitive fragile site into where the proto-oncogene c-ets has been mapped.

Abnormalities, Multiple↗
PubMed1986

Endocrine evaluation in a patient with MURCS association and ovarian agenesis.

A new case of Mullerian duct aplasia, renal aplasia, and cervicothoracic somite dysplasia (MURCS association) in a 16-yr-old female patient is reported. In addition, agenesis of the right ovary plus hypoplasia of the right craniofacial bones were also present. Dynamic tests of anterior pituitary reserve (LH-RH, TRH and hypoglycemia) showed normal responsiveness of this gland in terms of LH, FSH, TSH, prolactin and growth hormone secretion, whilst a subnormal plasma cortisol response to hypoglycemia and exogenous ACTH (in the presence of unilateral adrenal agenesis) was found. Functional integrity of the hypothalamic-pituitary-ovarian axis was also documented. The presence of two additional and previously unreported congenital anomalies in this patient with MURCS association underlines the wide spectrum of the syndrome.

Abnormalities, Multiple↗
PubMed1986

A joint international study on the epidemiology of hypospadias.

A descriptive epidemiological study of hypospadias has been made utilizing data from seven malformation surveillance systems round the world: Denmark, Hungary, Italy, Mexico, South America, Spain, and Sweden. The joint material represents 8,122 boys with hypospadias, 7,419 of which were "isolated", that is, with no other known malformation except those obviously related to hypospadias (undescended testis, hydrocele, scrotum anomalies). The main study was based on the infants with isolated hypospadias, but an analysis of multimalformed infants with hypospadias was also made. The registered birth prevalence of isolated hypospadias varied much among the seven programs. For the years 1980-1981, the lowest recorded birth prevalence was 0.26 (Mexico) and the highest, 2.11 (Hungary). An analysis of ascertainment was made for three programs: Denmark, Hungary, and Sweden. While some uncorrect registration of infants as hypospadiac were detected, a strong underascertainment of varying degree was seen. In Hungary and Sweden, where the highest birth prevalences were recorded, there was a 30-40% underascertainment of cases later operated on; in Denmark underascertainment was still larger. When correction was made for underascertainment, the Danish and Swedish birth prevalences of isolated hypospadias were very similar. No information on ascertainment was available for the other systems, but it seems very unlikely that the low birth prevalences recorded in Mexico and South America can be solely explained by underascertainment. Therefore, it appears that true differences in the prevalence at birth of hypospadias do exist. There are no indications that the different birth prevalences depend on inclusion or exclusion of mild (distal) forms of hypospadias. There is an apparent inverse correlation between fertility in a population (estimated from mean parity in control women) and the birth prevalence of isolated hypospadias. Within each program geographical variations in birth prevalence could be seen, but the interprogram variation was larger than the intraprogram one. There is an effect of maternal age and parity on the intensity ratio of isolated hypospadias. This effect varies among programs. The variability for mothers under 20, parity 1, seems to be inversely related to the proportion of delivered women belonging to that age class. With increasing maternal age, especially within parity 1, an increased hypospadias intensity ratio is seen. Infants with isolated hypospadias show a lower birth weight and to some extent also a shorter gestational length than do controls.(ABSTRACT TRUNCATED AT 400 WORDS)

Abnormalities, Multiple↗
PubMed1985

Fetal mortality in sibships with one or more affected members with oral clefts.

We investigated the fetal mortality in 903 sibships with at least one member having cleft lip with or without cleft palate [CL(P)] and 213 with at least one individual affected with cleft palate (CP) derived from three different data sources in México. The frequency of fetal wastage (abortion and/or stillbirth) was not increased in sibships where the propositi had cleft lip and palate (CLP) as compared with cleft lip (CL) nor in those where index cases had a bilateral lesion as compared to a unilateral one, nor when the index cases with CL(P) were female rather than males, nor when the index case was a female with bilateral lesion as compared to males with a unilateral one. Similarly fetal mortality was not increased in sibships in which the propositus had CP compared to those in which the index case was a female. These findings are contrary to some reports that claim to support a two-threshold model according to which individuals reaching the first one would be born with an oral cleft, and those reaching the second would be aborted. Our results, together with others, suggest the possibility that liability to oral clefts is independent of liability to fetal wastage.

Abortion, Spontaneous↗
PubMed1985

Endocrine and biochemical studies in a 46,XY phenotypically male infant with 17-ketosteroid reductase deficiency.

A 46,XY phenotypically male patient with 17-ketosteroid reductase deficiency is described. The patient was a 6-month-old infant who presented with micropenis and bilateral cryptorchidism. Baseline plasma levels of testosterone (T), delta 4-androstenedione (delta 4A), and 5 alpha-dihydrotestosterone (5 alpha-DHT) were within the normal range [patient: 0.17 (T), 0.12 (delta 4A), and 0.032 (5 alpha-DHT) ng/ml; normal infants: 0.03-0.55 (T), 0.14-0.45 (delta 4A), and 0.01-0.23 (5 alpha-DHT) ng/ml]. hCG administration induced a significant rise in plasma delta 4A levels (up to 8.39 ng/ml) and a slight increase in T and 5 alpha-DHT levels. The delta 4A/T ratios before and during the hCG challenge were 0.86 and 55.61, respectively (controls: 0.83 and 0.13). Incubation of genital skin-derived fibroblasts from the patient with either [3H]T or [3H] delta 4A revealed normal formation of delta 4A from T and diminished conversion of delta 4A to T. The development of a male phenotype despite both a testicular and peripheral 17-ketosteroid reductase deficiency is difficult to explain. It is possible that the fetal testes were the source of sufficient amounts of T during the early periods of embryonic life, and that late onset of the enzyme deficiency prevented the development of completely normal male genitalia. The in vitro finding of normal T to delta 4A conversion by the mutant fibroblasts suggests that in this particular tissue 17 beta-reduction and dehydrogenation of androgens are mediated by two isoenzymes with distinct substrate and/or cofactor specificities.

17-Hydroxysteroid Dehydrogenases↗
PubMed1983

Sister-chromatid exchanges and cell kinetics in human and rabbit lymphocytes exposed in vivo and in vitro to 2-bromo-alpha-ergocryptine.

The possible mutagenic and DNA-synthesis inhibitory effects of 2-bromo-alpha-ergocryptine, a new semi-synthetic ergot alkaloid, was studied in human and rabbit lymphocytes exposed to it in vivo and in vitro. The analysis of SCE was mainly used to evaluate potential mutagenicity, and the mitotic and DNA-synthesis inhibition was explored by examining the proportions of first-, second- and third-division metaphases in the corresponding lymphocyte cultures. The results obtained show that 2-bromo-alpha-ergocryptine does not induce SCE in the cell systems tested, or structural chromosome aberrations in human lymphocytes in vivo. On the other hand, a marked mitotic inhibitory effect and associated cell kinetic changes could be clearly attributed to the drug, probably related to its cytotoxicity.

Animals↗
PubMed1982

Distribution of ABO blood groups and other genetic markers in mothers of infants with congenital malformations.

The distribution of ABO and Rh (antigen D) blood groups and of serum albumin, haptoglobin and transferrin variants, in a group of mothers of malformed newborns was investigated. In the first phase of the study, the results showed borderline statistical differences in the distribution of the transferrin types between the study group and a suitable control population. The second phase of the research, where only transferrin phenotypes were studied, showed the same trend as in the first one, but the results were not statistically significant. We conclude that probably there are no true distribution differences, but that it would be desirable to study this problem in a different ethnic group.

ABO Blood-Group System↗
PubMed1982

Comparative cytogenetic studies in Macaca arctoides with other species of Macaca and man.

Chromosome studies of 5 males and 5 females of the species Macaca arctoides from Thailand were performed and the G, C and NOR banding patterns obtained for comparison with other species of the genus Macaca and with the human karyotype. The cytogenetic analysis showed a complement of 42 chromosomes. Of the 20 autosomal pairs, 15 are submetacentric and 5 almost metacentric. Pair number 9 presents a large secondary constriction, which corresponds to the only nucleolar organizer region of the whole genome, and has giant satellites in the short arms. In regard to the sex chromosomes, females have a pair of submetacentric chromosomes with a G banding pattern identical to that of the human X, while the males have one X and a very small Y chromosome.

Animals↗
PubMed1981

Constitutive heterochromatin polymorphisms in patients with malignant diseases.

The frequency of constitutive heterochromatin heteromorphisms was assessed in peripheral blood cultures of 23 patients with various malignant diseases and in their respective controls, formed by cancer-free same sex siblings of the propositi. The results showed no significant differences between the cancer and the control groups, except for chromosome 1 in breast cancer, where polymorphisms were more frequent in the controls than in the patients. Our results do not support previous data reported by others, and although there are differences in the type of malignancies studied by us and them, we believe that our control group is a more appropriate one for this particular type of study.

Adult↗
PubMed1981

Clinical and endocrine spectrum in patients with the 45,X/46,XY karyotype.

Cytogenetic and endocrine studies were performed in five unrelated 45,X/46,XY individuals in an attempt to correlate them with their clinical expression and gonadal morphology. A lack of a consistent pattern between cytogenetic findings and phenotype was observed. Endocrine studies revealed a wide spectrum of hypothalamic, pituitary, and gonadal hormone production as assessed by the base line levels of LH, FSH, T, and delta 4-A and their responses to appropriate exogenous stimulation (LH-RH and HCG). An adequate correlation between endocrine findings with gonadal morphology and phenotype could be established; thus demonstrating that patients with this particular chromosome complement have a functional integrity of the gonadotropin hypothalamic pituitary activity modulated accordingly with the gonadal function of each particular case.

Adolescent↗
PubMed1981

Frequency and types of induced and spontaneous chromosome aberrations in relation to cell kinetics.

Induced and spontaneous structural chromosome aberrations (SCA) were studied in a child accidentally radiated with a high dose of 192Ir, and in three sibs with Fanconi's anemia, analyzing by separate first division metaphases (FDM) and second division metaphases (SDM). The results showed that the number of SCA, number of cells with aberrations, and SCA per cell were markedly higher in FDM in all patients. Furthermore, for some type of structural changes like dicentric chromosomes and chromatid interchanges, the differences were particularly striking. The importance of ascertaining FDM identified with proper techniques, for the study of the clastogenic effect of environmental agents and some aspects related to the differences in cytogenetic features found in diverse tissues in Fanconi's anemia are discussed.

Anemia, Aplastic↗
PubMed1980

Late-appearing Philadelphia chromosome in two patients with chronic myelogenous leukemia.

We describe two patients with typical myelogenous leukemia, who at the beginning of the disease lacked the Philadelphia chromosome in bone marrow cells, and 90 and 42 days later, respectively, its presence was shown in all cells analyzed from that tissue. These findings are compatible with the possibility that at least occasionally Ph1 occurs secondarily in already leukemic cells. The rapid change form Ph1- to Ph1+ CML in one of the patients (42 days), suggests the possibility that in addition to Ph1+ cells enjoying marked selective advantage, this change is induced simultaneously in multiple bone marrow cells.

Adult↗