Search PubMed⌕ Search

Biomedical subjects

G Neri

Publications and source records attributed to G Neri.

At least 307 records · Page 17Linked to original sources

Reproductive risks for translocation carriers: cytogenetic study and analysis of pregnancy outcome in 58 families.

Here we report on studies of the reproductive risks for heterozygous carriers of chromosome translocations. Pregnancy outcome, breakpoints, mode of segregation of the translocated chromosomes, and resulting chromosome imbalance were analyzed in 58 families (46 with reciprocal and 12 with Robertsonian translocations) ascertained for birth of a malformed child, recurrent spontaneous abortion, or hypogonadism. These families include a total of 122 informative sibships. The analysis of the data, after correction for ascertainment bias, showed that the incidence of spontaneous abortion is nearly 50% in reciprocal and between 20 and 25% in Robertsonian translocation families ascertained for malformed child or recurrent abortion. The risk of malformed infants with unbalanced genome is approximately 6% among the liveborn offspring of reciprocal translocation carriers and 23% among the liveborn offspring of carrier mothers of t(14q21q). The distribution of the breakpoints on the chromosomes involved in reciprocal translocations ascertained through a malformed child is nonrandom, with an excess on chromosomes 5, 9, 13, and 15. The study of chromosome imbalance, expressed as gain or loss of a portion of genetic information relative to the total haploid autosome length (percent HAL), shows that among the common types of disjunction-segregation leading to unbalanced gametes, adjacent 1 seems to be the one producing on the average the least level of genome imbalance. This explains why it is the most frequently observed type of segregation giving rise to gametes from which subjects with a chromosome imbalance compatible with life can be generated.

Abortion, Habitual↗

Appearance of altered cell-surface fucosyl glycopeptides in concomitance with chromosomal alterations in the gross virus-infected pre-leukemic thymus of the rat.

The appearance of a class of fast-eluting cell-surface glycopeptides that are encountered almost exclusively in malignant and certain pre-malignant cells was monitored in the course of leukemogenesis in the thymus of rats injected at birth with Gross leukemia virus. The altered glycopeptides appeared as early as 15 days after virus injection, when the animals were still clinically healthy and no histological signs of the disease were present in the thymus. Their amount was further increased at 30 days, and reached a maximum in the fully developed lymphoma. The development of this early phenotypic marker of malignancy appeared to be concomitant with that of chromosomal anomalies in the thymus. Since these anomalies are non-random, the existence of a causal relationship between the glycopeptide change and the loss of specific chromosomes might be hypothesized.

AKR murine leukemia virus↗

[Myasthenia and sleep].

A Central Nervous System (CNS) acetylcholine receptors involvement in Myasthenia Gravis (MG) has been suggested but never fully demonstrated. On the other hand, although the question concerning the neurotransmitters connected to REM sleep is still unsettled, the importance of acetylcholine as a neurotransmitter involved in the maintenance of this sleep stage has been outlined. The spontaneous night sleep organization has been studied in 9 male subjects with MG and results are compared with those obtained in normal subjects matched for age and sex. Statistically significant differences have been found: 1) slow-waves sleep better represented in MG patients; 2) average REM period length shorter in MG patients; 3) instability of the EEG consisting in a tendency toward lightening of sleep. These findings may confirm the presence of a disturbance in the CNS cholinergic activity of MG patients.

Adult↗

Cytogenetic findings in 4952 prenatal diagnoses. An Italian collaborative study.

The development of prenatal diagnosis in Italy was made difficult by the restrictions of the old abortion law and only in recent years has a consistent number of cases been investigated. We report the experience on prenatal chromosome diagnosis of ten Italian centers participating in a collaborative study on 4952 diagnoses performed from 1972 to 1980. The main indication groups were: advanced maternal age (2882 cases), previous child with chromosome anomaly from parents with normal karyotype (847 cases), and chromosome anomaly in one parent (97 cases). The other indications for amniocentesis, including cases without a cytogenetic risk, have been assembled into a "miscellaneous" group (1126 cases). We found 125 abnormal fetal karyotypes (2.5%) of which 89 were unbalanced (1.8%). The frequencies and types of chromosome anomalies are reported in detail for each indication group and are compared with the corresponding one from the European Munich Conference. The great majority of these Italian data were not included in the Munich report.

Chromosome Aberrations↗

Effects of ACTH on the zona glomerulosa of sodium-loaded timolol maleate-treated rats: stereology and plasma hormone concentrations.

The effect of chronic ACTH administration on the growth and aldosterone secretion of the zona glomerulosa of sodium-loaded timolol maleate-treated rats was investigated by stereological and radioimmunological techniques. Combined sodium loading and timolol maleate administration induced a significant atrophy of the zona glomerulosa and its cells. The plasma concentration of aldosterone was significantly decreased, while that of corticosterone did not vary. ACTH administration completely reversed zona glomerulosa atrophy, and the plasma concentration of corticosterone was noticeably enhanced, whereas that of aldosterone underwent a further decrease. This data suggests that in the absence of the other adrenoglomerulotrophic factors, ACTH stimulates the growth of the zona glomerulosa, but transforms its parenchymal elements to a functional fasciculata cell type.

Adrenal Glands↗

Sleep and human cerebellar pathology.

The organization and the quantitative evaluation of sleep stages were studied in patients with cerebellar syndrome. 25 polygraphic night recordings were scored according to the criteria suggested by Rechtschaffen & Kales (1968) and the sleep parameters investigated were referred to those indicated by Williams et al. (1974). The results matched with a homogeneous sample of normal subjects. Significant alterations were observed for several parameters of sleep, and the possible causes discussed.

Adolescent↗