Biomedical subjects

G Neri

Publications and source records attributed to G Neri.

At least 235 records · Page 13Linked to original sources

PubMed1991

Acute action of polypeptide YY (PYY) on rat adrenocortical cells: in vivo versus in vitro effects.

Polypeptide YY (PYY), a 36-amino-acid peptide contained in high concentration in the chromaffin granules of adrenal medullary cells, significantly raised aldosterone (but not corticosterone) plasma level, when acutely administered intraperitoneum to rats at a dose of 25 microM.kg-1. Conversely, the exposure to PYY (10(-6) M) notably and specifically depressed both basal and ACTH-stimulated production of 18-hydroxylated steroids (aldosterone, 18-hydroxy-corticosterone and 180H-DOC) by isolated rat zona glomerulosa cells. The discrepancy between in vivo and in vitro results is tentatively explained by assuming that the direct inhibitory effect of PYY on aldosterone secretion by rat zona glomerulosa is masked in vivo by the interference of this peptide with one or more of the various factors that are involved in the multifactorial regulation of zona glomerulosa function.

18-Hydroxycorticosterone↗

PubMed1991

Chronic myelogenous leukemia in the course of chronic lymphocytic leukemia: evidence for an independent clonal origin.

We report on a 69-year-old man who developed Ph-positive CML 6 years after the onset of B-cell CLL. When CML was diagnosed, both malignant cell populations were detected in bone marrow and peripheral blood. Peripheral leukocytes were fractionated by Ficoll-Hypaque density gradient, and cytogenetic and molecular studies were performed on mononuclear cell and granulocyte-enriched populations. Mononuclear cells were stimulated with either PHA or PWM. In PHA-treated cultures 76% of the metaphases were Ph-negative, while after PWM stimulation 87% were Ph-positive. A bcr rearrangement was observed in DNA from the granulocyte-enriched fraction, but not in mononuclear cells. On the contrary the IgH locus resulted in monoclonally rearranged DNA, only in peripheral blood mononuclear cells. These results indicate that the two neoplastic populations originated independently.

Aged↗

PubMed1991

Corticotropin-releasing hormone (CRH) directly stimulates corticosterone secretion by the rat adrenal gland.

Corticotropin-releasing hormone (CRH) acute ip administration (10 micrograms) significantly increased the blood concentration of corticosterone (B) in hypophysectomized rats, without inducing any rise in the level of circulating ACTH. CRH (10(-6) M) did not affect B production by isolated rat adrenocortical cells, but notably enhanced that by adrenal slices including both cortex and medulla. This last effect of CRH was blocked by corticotropin inhibiting peptide (CIP), at a concentration (10(-6) M) which was found to completely annul B response of adrenal slices to ACTH (10(-8) M). In light of many findings indicating that adrenal medulla contains and releases CRH and numerous POMC-derived peptides, the hypothesis is advanced that an intra-adrenal CRH/ACTH mechanism may be operative in the control of adrenocortical steroid-hormone secretion.

Adrenal Glands↗

PubMed1991

Interleukin-1 beta enhances corticosterone secretion by acting directly on the rat adrenal gland.

Interleukin-1 (IL-1), a monokine released by activated monocytes during the acute phase of the inflammatory responses, has been reported to enhance hypophyseal ACTH release mainly by stimulating hypothalamic CRF secretion. We investigated a possible direct effect of IL-1 beta on the adrenal gland of the rat. IL-1 beta was found to dose-dependently (4-8 micrograms/kg) raise corticosterone (B) blood concentration in hypophysectomized rats, without inducing any significant increase in the level of circulating ACTH. IL-1 beta did not affect B production by either isolated rat inner adrenocortical cells or fragments of adrenocortical autotransplants lacking chromaffin cells, but dose-dependently (10(-8)-10(-6) M) enhanced that by adrenal slices including both cortex and medulla. The secretory effect of IL-1 beta (10(-6) M) was completely blocked by both alpha-helical-CRF (10(-6) M) and corticotropin-inhibiting peptide (10(-6) M), two competitive inhibitors which (at these concentrations) were able to annul B response of adrenal slices to CRF (10(-6) M) and ACTH (10(-8) M), respectively. In light of many findings indicating that adrenal medulla contains and releases CRF and numerous POMC-derived peptides (including ACTH), the hypothesis is advanced that the mechanism underlying the direct secretory effect of IL-1 beta on the adrenal gland may involve the activation of an intraadrenal CRF/ACTH system.

Adrenal Glands↗

PubMed1991

[Long-term evaluation of a new single lead VDD pacemaker].

Since June 1988 we have implanted 36 VDD pacemakers with single lead catheter which has floating differential sensing (Phymos). The patients were affected by 2nd and 3rd degree AV block with normal sinus node function. The reliability of the pacing system was assessed acutely and after 1 and 3 months and then every six months with ECG, Holter 24 hours monitoring, exercise stress test and nifedipine test. Two patients died during the follow-up period and two had atrial fibrillation. In the remaining patients an AV synchronization between 95 and 100% was demonstrated.

Adult↗

PubMed1991

Effects of prolonged treatment with adrenocorticotropin on the morphology and function of rat adrenocortical autotransplants.

Regenerated adrenocortical nodules were obtained by implanting in the musculus gracilis of rats fragments of the capsular tissue of their excised adrenal glands. Five months after operation, transplanted rats showed a slightly elevated blood concentration of adrenocorticotropin (ACTH), a moderately reduced plasma level of corticosterone (PBC) and a very low concentration of circulating aldosterone (PAC). Regenerated nodules were well encapsulated, and from the connective capsule some septa dipped into the parenchyma. Subcapsular-outer (OZ) and inner (IZ) cells were similar to those of the zona fasciculata/zona reticularis (ZF/ZR) of the normal gland; juxta-septal (JZ) cells resembled those of the zona glomerulosa (ZG). Prolonged (14 days) ACTH infusion normalized PBC and caused a conspicuous hypertrophy of transplanted tissue, which was coupled with a marked hypertrophy of ZF/ZR-like OZ and IZ cells and a notable rise in the basal in vitro production of corticosterone. Conversely, ACTH infusion strikingly lowered PAC, reduced the number of ZG-like JZ cells, and decreased both basal and stimulated secretion of 18-hydroxylated steroids by transplants in vitro.

Adrenal Cortex↗

PubMed1991

[Post-infarction rupture of the interventricular septum. A report on 2 cases studied by color-coded Doppler].

Rupture of interventricular septum is an infrequent but serious complication of acute myocardial infarction. We report the cases of two patients admitted to our department for acute myocardial infarction whose clinical course was complicated by rupture of the interventricular septum. They died from cardiogenic shock on the 13th and 6th days. Two dimensional and color coded echocardiography correctly detected the presence and the site of the rupture.

Aged↗

PubMed1990

Differential expression of FRA16B in peripheral lymphocytes and bone marrow cells.

Expression of the rare fragile site FRA16B in chromosome band 16q22 was studied in bone marrow (BM) cells and peripheral blood lymphocytes (PBLs) from three unrelated subjects. Although FRA16B was detected only in PBLs from two healthy subjects who had been previously treated for non-Hodgkin's lymphoma (NHL), both cell types displayed FRA16B in a patient with chronic myelomonocytic leukemia (CMMoL). This variability in expression could be related to differences in the proliferative status of the cell populations or to differences in gene activity in the fragile site region.

Adult↗

PubMed1990

"C" trigonocephaly syndrome: clinical variability and possibility of surgical treatment.

We report on 3 new cases of C trigonocephaly syndrome. In addition to the findings characteristic of this condition, one of the patients also had a large omphalocele. This patient was referred from a suburban hospital with a diagnosis of Down syndrome, stressing the fact that C syndrome is still under-recognized and underdiagnosed. Another patient was diagnosed at birth and immediately submitted to craniosynostectomy. A second operation was performed 7 months later resulting in normal brain growth and close to normal psychomotor development at 3 years, in contrast to the third patient, who was not treated surgically and was severely retarded at 4 years.

Abnormalities, Multiple↗

PubMed1990

Trisomy 21: conference report and 1990 update.

The most relevant data and stimulating ideas presented and discussed at the symposium are briefly summarized. They centered around four major foci: the genotype, the phenotype, the pathogenesis of Down syndrome (DS), and the Down person. The molecular genetic approaches to the isolation of genes encoded by chromosome 21, the definition of a possible "critical region," and the acquisition of further insights on the origin of trisomy 21 were the main topics of the analysis of the genotype. The study of the phenotype concentrated essentially on three complex traits related to the nervous, immune, and hematologic systems, which show great sensitivity to developmental disturbances, with major effects on DS subjects' health and behavior. The difficulties of investigating the pathogenesis of the syndrome were outlined, but the theoretical bases for devising sound and complete experimental approaches were also delineated. Finally, the special attention that in the last decade the medical and sociopsychological sciences gave to Down persons was also underlined, and future developments indicated. DS still remains a challenge to science and medicine; however, from the symposium emerged a less pessimistic view on actual potentialities for a decisive advancement in its basic knowledge.

Down Syndrome↗

PubMed1990

Growth delay in Down syndrome and zinc sulphate supplementation.

Children affected with Down syndrome (DS) show deficient growth, immunodeficiency--especially concerning the T-cell population--and low plasma zinc levels. New growth charts have been recently proposed, and zinc supplementation to the diet has been reported to improve transiently the efficiency of the immune system. The aim of this study was to evaluate if in DS children zinc sulphate therapy could improve the growth rate and affect some endocrine parameters. We studied 22 patients (16 males and 6 females) who received zinc sulphate for 6 to 9 months. Fifteen of 22 patients studied reached a higher centile in their growth rate, whereas the remaining seven showed no change, at least to date. The average height velocity changed from 23.84 +/- 7.98 mm/6 months to 40.80 +/- 7.68 mm/6 months. Growth hormone serum level was 5.94 +/- 4.89 ng/ml compared with 7.49 +/- 6.75 ng/ml before and after therapy, respectively. Somatomedin serum level was 160.27 +/- 68.88 mU/ml and 205 +/- 124.07 mU/ml before and after therapy, respectively. In conclusion, zinc sulphate therapy of patients with DS affects not only the immune system, as previously reported, but can also accelerate growth.

Adolescent↗

PubMed1990

Pericentric inversion of chromosome 9: prevalence in 300 Down syndrome families and molecular studies of nondisjunction.

The incidence of Down syndrome (DS) families where one of the parents is an heterozygous carrier of pericentric inversion of the heterochromatic region of chromosome 9-inv(9) (qh) - was determined in 3 independent groups of 100 families each. The total number of 17 such families found in the sample is significantly greater than the expected number of 5.73 for a sample of non-DS families of equal size. Consequently, the statistical association of the presence of inv (9) (qh) in one parent with the birth of a DS offspring, and the correlative 3-fold increased risk of a DS child for such families, seem to be demonstrated. A study of the origin of nondisjunction, using restriction fragment length polymorphism (RFLP) segregation analysis with a sufficient number of chromosome 21 specific probes, has provided complete information in 7 of 8 available families. Although the statistical interpretation of the results is not straightforward, due to the small size of the sample, the observed data do not contradict the assumption that the presence of inv (9) (qh) in a parent increases, by a factor of about 3, the chance that the offspring will inherit an extra chromosome 21 from that parent. Nevertheless, gathering further data appears desirable because stronger evidence would have relevance both for clinical implications and for the understanding of the function of heterochromatin, particularly with respect to meiotic and mitotic processes.

Chromosome Inversion↗

PubMed1990

Analysis of 138 consecutive ovarian cancer patients: incidence and characteristics of familial cases.

Eight families with two or more first-degree relatives affected with ovarian carcinoma were identified among a series of 138 consecutive ovarian cancer patients. History of breast cancer was reported in six of the eight families. Five of 19 patients with familial cancer developed ovarian cancer as a second primary tumor following breast carcinoma, whereas only 6/130 sporadic cases had a previous history of breast cancer. No significant difference was detected in clinical and pathological features between sporadic and familial cases. However, in three high-risk families ovarian cancer tended to develop at a younger age compared with other familial cases and with sporadic occurrences, and nulliparity was less frequent in the familial group. These observations emphasize the need to take into account multiple factors-in addition to positive family history-for the evaluation of genetic predisposition to ovarian carcinoma.

Carcinoma↗

PubMed1990

Effects of neuropeptide-Y and substance-P on the secretory activity of dispersed zona-glomerulosa cells of rat adrenal gland.

Neuropeptide-Y (NPY) and substance-P (SP), two peptides contained in the chromaffin granules of adrenal medullary cells, were found to partially inhibit both basal ACTH-stimulated release of aldosterone and 18-hydroxy-corticosterone by isolated rat zone-glomerulosa cells, without affecting the overall post-pregnenolone yield or basal progesterone output. Conversely, the exposure to both peptides increased 11-deoxy-corticosterone and corticosterone secretion. These data indicate that NPY and SP are able to exert a direct suppression of 18-hydroxylase activity in rat zona-glomerulosa cells, without conceivably altering the earlier steps of aldosterone synthesis. The possible physiological implications of these findings are discussed in light of previous studies suggesting a net adrenoglomerulotrophic effect of NPY and SP in vivo.

18-Hydroxycorticosterone↗

PubMed1990

Multicenter comparison of once- and twice-daily isradipine to hydrochlorothiazide for the treatment of hypertension in elderly patients.

After 8 weeks of isradipine, a twice-a-day dihydropyridine calcium channel blocker, 49% of elderly patients showed a complete response (sitting diastolic blood pressure less than or equal to 85 mm Hg) and 36% showed a partial response (sitting diastolic blood pressure decrease greater than or equal to 10 mm Hg) for an 85% total response rate. Hydrochlorothiazide gave a complete response in 36% of the patients and a partial response in 33%, for a 69% total response rate (p less than 0.0046). Because elderly subjects have reduced clearance for many drugs, we determined how those who responded to twice-a-day administration would respond to once-a-day administration. After 4 weeks of isradipine administered once a day, 54% of the patients showed a complete or partial response, whereas 38% of the patients who were changed to placebo showed a response. In contrast, 82% of patients receiving hydrochlorothiazide once a day showed a response, whereas 60% of patients who were changed to placebo showed a response. These data indicate that the standard formulation of isradipine was not effective when administered once a day.

Aged↗

PubMed1990

Brachy/ectrodactyly and absence or hypoplasia of the fibula: an autosomal dominant condition with low penetrance and variable expressivity.

A complex dysostosis characterized by brachy- and/or ectrodactyly and fibular hypoplasia was found in two distantly related individuals. The proposita, aged 25 years, showed metacarpal and phalangeal hypoplasia on both hands, ectrodactyly on both feet, and nearly complete bilateral absence of the fibula. Only milder acromelic defects were detected in a second cousin. A similar pattern of skeletal involvement had been previously described in an unrelated Italian family. The peculiar segregation pattern can be explained by autosomal dominant inheritance with low penetrance and variable expressivity.

Abnormalities, Multiple↗

PubMed1990

Investigations on the morphology and function of adrenocortical tissue regenerated from gland capsular fragments autotransplanted in the musculus gracilis of the rat.

This paper describes the function and morphology of regenerated adrenocortical nodules obtained by implanting, in the musculus gracilis of rats, several (n = 6-7) fragments of the capsular tissue of their excised adrenal glands. Four months after the operation, each bilaterally adrenalectomized rat developed six or seven well encapsulated adrenocortical nodules about 2-3 mm in diameter and always lacking chromaffin cells, and displayed almost complete normalization of basal and stimulated blood levels of corticosterone, but not of aldosterone. In vitro study showed that regenerated nodules were well functioning as far as glucocorticoid production was concerned. Accordingly, electron microscopy and stereology indicated that the majority of the parenchymal cells (independently of their location in the outer subcapsular, middle, or inner portions) closely resembled those of the zonae fasciculata/reticularis of the adrenal gland of age-matched sham-operated rats. By contrast, regenerated nodules evidenced a relative impairment in aldosterone secretion, and this was coupled with the presence of only a few zona glomerulosa-like cells. Such cells were grouped in small islets located near the few connective trabeculae detaching from the capsule, and autoradiography showed that they were the only parenchymal elements of the nodule able to bind [125I]angiotensin-II. The possibility is suggested that the paucity of zona glomerulosa-like cells in regenerated nodules could be ascribed to the absence of zona medullaris, which is currently thought to exert a paracrine control on the growth and secretion of zona glomerulosa in the rat adrenal glands.

18-Hydroxycorticosterone↗

PubMed1990

[Aneurysm of the thoracic aorta as a cause of heart failure. Description of a case].

The Authors describe the case of a 81 year old patient admitted to their department for cardiac failure. The patient was submitted to chest x-ray, bidimensional and Doppler echocardiography and computerized tomography. These exams identified the presence of an enormous aneurysm of thoracic and abdominal aorta. Intraluminal thrombus was present. The aneurysm compressed the left atrium and obstructed diastolic filling of left ventricle. Because of the poor conditions of the patient, surgery was not taken in account.

Aged↗