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Biomedical subjects

A Piazza

Publications and source records attributed to A Piazza.

At least 109 records · Page 6Linked to original sources
PubMed1987

Abnormal distribution of epididymal antigens on spermatozoa from infertile men.

An antiserum raised against human epididymal proteins associated with ejaculated sperm was used to test the hypothesis that the amount and/or localization of these antigens may be altered in men with infertility. With the use of immunofluorescence we found that in sperm from fertile donors 88.4% of the cells had the antigens localized over the acrosomal cap only and 1.3% had most of the antigens at extraacrosomal sites. Fifteen of the 26 infertile men (P1) studied had a similar relative distribution of antigens, but the remaining 11 patients (P2) had a 38-fold increase in cells with extraacrosomal localization of the antigens (40%, P less than 0.005). Using flow cytometry to quantitate immunofluorescence, content of antigen on sperm from patients from population P1 (680 +/- 60 V X 10(-4)) was not different from that of control (835 +/- 53 V X 10(-4], whereas it was significantly lower in sperm from patients from population P2 (554 +/- 64 V X 10(-4), P less than 0.005). Differences could not be correlated with parameters measured by routine semen analysis. Our results suggest a possible relationship between the decreased amount of epididymal antigens or their altered localization on sperm and the infertility of patients from population P2.

Adult↗
PubMed1986

Mental health care in Southern Italy: application of case-control methodology for the evaluation of the impact of the 1978 psychiatric reform.

A survey to analyse patients' characteristics and the care delivered to them was conducted in several psychiatric facilities, covering the whole range of care offered in the public sector in two regions of Southern Italy. A case-control method of analysis was chosen, and the relative risk estimates (RR), together with their 95% confidence intervals (CI), of being in custodial facilities were computed, comparing patients treated in custodial institutions ('cases') with those in community-based services ('controls') in respect of social and clinical variables. Factors more strongly associated with custodial treatment were: illiteracy (RR = 2.4), unmarried status (RR = 2.4), a history of prolonged illness (RR = 7.6), organic diagnosis (RR = 2.6), previous custodial treatment (RR = 3.9), and expected poor social functioning (RR = 2.4). The suitability and advantages of the case-control method of analysis in the field of psychiatric care evaluation are discussed.

Adult↗
PubMed1986

Surnames in Sardinia. III. The spatial distribution of surnames for testing neutrality of genes.

1. A study on heterogeneity of males' surnames over time and space in the island of Sardinia was carried out using data from consanguineous marriages (1800-1970) and telephone directories (1978). 2. Variation of frequency of surnames over time is barely significant and 10 times lower than that over space, which is very highly significant. 3. For sufficiently frequent surnames the estimate of the Wahlund variance, calculated from chi 2 for heterogeneity in space, is independent of the frequency of a surname: this supplies evidence of neutrality in line with that obtained from the frequency distribution of surnames. 4. The Wahlund variance, W (also called FST), decreases regularly as the average size of the area considered (number of individuals per area, N) increases. The estimate of the parameter beta in the relation W = KN beta could be of interest for the study of population structure. 5. A correction factor of 1/4 must be made on the surnames' variance in consideration of their haploid unisexual transmission. 6. It is suggested that surnames could provide a baseline for estimating the value of Wahlund variance under random genetic drift and hence evaluating whether a gene behaves as selectively neutral. 7. The distribution of the Wahlund variances obtained from two sets of gene frequency data as compared with that obtained in comparable conditions for surnames in the same areas seems to show that most genes behave as neutral, with the exception of a few, with high W values, which presumably have been under different selection pressures in the area examined.

Consanguinity↗
PubMed1986

The HLA system in Italy.

4,902 Italians were typed for HLA-A antigens, 4,721 for HLA-B and 1,503 for HLA-C. The samples, which were composed of unrelated, healthy individuals born in Italy, were used for estimating HLA-A, HLA-B and HLA-C gene frequencies with the maximum-likelihood method. Different Italian regions showed significant differences in the HLA alleles, providing further evidence for the genetic heterogeneity of the Italian population. HLA gene frequencies place continental Italy and Sicily in a position which is similar to that of other Mediterranean populations, whereas the genetic isolation of Sardinia is quite evident. The most significant linkage disequilibrium values found in the Italian population (except for Sardinia) were in agreement with those observed in other Caucasian populations. The difference between Northern and Southern Italy and between continental Italy and Sardinia was emphasized by the linkage disequilibrium values and by the principal-component analysis as well.

Gene Frequency↗
PubMed1986

Genetic markers of cluster headache and the links with the lithium salts therapy.

The existing relationship between genetic markers of the cluster headache and the efficacy of lithium salts therapy was described in the present study. Thirty-five patients suffering from cluster headache, who were already typed for the HLA antigens, were studied. Typing was carried out with the microlymphocytotoxicity technique used by US National Institutes of Health. The patients were treated with lithium carbonate for a period of three months. Three parameters for evaluation of the efficacy of lithium therapy was used: the percentage of improvement, the wake-sleep rhythm and the pupil diameter measurement. The parameters were statistically (Student's t-test) evaluated and it was possible to separate two subgroups of patients: "responders" and "non-responders" to the lithium therapy. The phenotypical frequencies in the two subgroups was analysed using the chi 2 test, Data emerging showed a higher frequency of antigen HLA-B18 (23.8% versus 0%; p less than 0.005 pc less than 0.06) and of antigen HLA-A9 (42.9% versus 14.3%) in the "responders" subgroup. In the "non-responders" subgroup a higher frequency of antigen HLA-A1 (35.7% versus 14.3%) was found.

Adult↗
PubMed1986

Vitamin E supplementation in hemodialysis patients: effects on peripheral blood mononuclear cells lipid peroxidation and immune response.

Lipid peroxidation and vitamin E levels in peripheral blood mononuclear cells (PBMC) were studied in 10 patients on maintenance hemodialysis. Significant increases of PBMC malonyldialdehyde (MDA) were detected, together with low vitamin E levels. After a fifteen-day-course of parenteral vitamin E supplementation, PBMC MDA reverted to normal values, while PBMC vitamin E levels remained lower than controls. In a parallel study an immunological monitoring was performed in the same patients before and after vitamin E supplementation. NK activity and PHA blastogenesis were not influenced by treatment, while a reduction of the number of OKT8+ lymphocytes were observed after vitamin E therapy. It is tempting to speculate that peroxidative damage of PBMC cell membranes in hemodialysis patients could, by impairing their functionality, influence immune responses and expression of functionally relevant membrane determinants.

Adult↗
PubMed1985

[Various parameters of hemostasis in patients with chronic liver diseases].

The aim of the study was to investigate the nature and the possible correlations between abnormalities of platelet function and haemostatic and fibrinolytic activity in a group of 33 patients with biopsy-proven chronic liver disease. A slight decrease in prothrombin activity, AT III and plasminogen levels was noticed in the patients studied. Significantly enhanced levels of intraplatelet 5HT was also found in patients with cirrhosis and in those with chronic active hepatitis. Changes in these parameters were generally independent from each other, the only correlation being found between prothrombin activity and AT III levels in patients with cirrhosis.

Adult↗
PubMed1985

Genetic and population structure of four Sardinian villages.

Data on microgeographic population structure on four neighbouring villages of Sardinia island (Italy) are presented and discussed. Two villages are located in the lowlands where malaria from Plasmodium falciparum was endemic until the eradication of paludism. The other two villages are located in the highlands and they were malaria-free because of the altitude. Census data, inbreeding, migration matrices and surname distributions have been collected. The genetic differentiation of the four villages, tested for 31 genetic polymorphisms (106 alleles), is only in part compatible with migration rates inferred from demographic data. The possible adaptive nature of some genetic markers with respect to malarial resistance is discussed. Ambiguous results from population genetics quantitative methods do not support definite answers.

Blood Group Antigens↗
PubMed1985

HLA sharing in couples with recurrent abortion.

To investigate the interactions between HLA region and recurrent abortion we examined the HLA-A and HLA-B antigen frequencies, the degree of HLA sharing, and the incidence of anti-HLA antibodies in 18 recurrent abortion and in 23 control couples. HLA antigens with low distribution (less than 25% of phenotype frequencies in the general population) represent 38.5% of the HLA antigens shared between recurrent abortion partners. No antibodies against partners' HLA antigens were detected in recurrent abortion women, while such antibodies were present in 39.1% of control women (p = 0.002).

Abortion, Habitual↗
PubMed1985

Genetic analysis of eight linked polymorphisms within the human immunoglobulin heavy-chain region.

Genetic analyses of multiple restriction fragment length polymorphisms, revealed by a single DNA probe containing the switch region of the immunoglobulin constant heavy-chain (IgCH) mu gene, are presented here in detail. Five of the polymorphic loci segregate in complete linkage with IgCH allotypic markers, while one appears to be located at more than 10 centimorgans from the IgCH region. A study of over 100 random haplotypes typed at eight linked loci, including the Ig switch polymorphisms and the classical Gm-Am allotypes, allowed us to construct an evolutionary tree by which each haplotypic variant can be derived one from the other either by single-step mutation or by recombination. A few of the recombinant haplotypes appeared to carry large DNA duplications that could be explained by unequal crossing over; others might postulate gene-conversion events. Linkage disequilibria observed between the IgCH-linked loci were compared with expected ones. A heterogeneous distribution of recombination rates is clearly documented, a "hot" region of recombination being present between the gamma 2 and switch alpha 2 loci.

Alleles↗
PubMed1985

High frequency of nonclassical steroid 21-hydroxylase deficiency.

Nonclassical steroid 21-hydroxylase deficiency is an autosomal recessive disorder that is defined by clinical and hormonal criteria that distinguishes it from the classical 21-hydroxylase deficiency. No estimates of the gene frequency of nonclassical 21-hydroxylase deficiency, also called attenuated, late-onset, acquired, and cryptic adrenal hyperplasia, have been published thus far. Here, we have used HLA-B genotype data in families containing multiple members affected with nonclassical 21-hydroxylase deficiency together with the results of quantitative hormonal tests to arrive at estimates of gene and disease frequencies for this disorder. We found nonclassical 21-hydroxylase deficiency to be a far more common disorder than classical 21-hydroxylase deficiency, which occurs in 1/8,000 births. The prevalence of the disease in Ashkenazi Jews was 3.7%; in Hispanics, 1.9%; in Yugoslavs, 1.6%; in Italians, 0.3%; and in the diverse Caucasian population, 0.1%. The gene for nonclassical 21-hydroxylase deficiency is in genetic linkage disequilibrium with HLA-B14 in Ashkenazi Jews, Hispanics, and Italians, but not in Yugoslavs or in a diverse, non-Jewish, Caucasian group. The penetrance of nonclassical 21-hydroxylase deficiency gene in the HLA-B14 containing haplotypes was incomplete. Thus, nonclassical 21-hydroxylase deficiency is probably the most frequent autosomal recessive genetic disorder in man and is especially frequent in Ashkenazi Jews, Hispanics, Italians, and Yugoslavs.

Adrenal Hyperplasia, Congenital↗
PubMed1984

Addition of androgens to cultured hamster epididymis increases zona recognition by immature spermatozoa.

The ability of spermatozoa recovered from the successive segments of the hamster epididymis to bind to the zona pellucida was studied and a major increase was found as spermatozoa passed from the proximal to the distal portion of the corpus epididymidis (1.95 compared with 20 spermatozoa bound/egg). Tubules from the proximal epididymis were cultured in conditions which preserved the motility of the contained spermatozoa for 48-72 h. Addition of 2 microM-5 alpha-DHT to the culture medium for 17 h stimulated the incorporation of 3H-labelled amino acids into several protein bands whose mobility in polyacrylamide gel electrophoresis was coincident with those of glycoproteins EP1-EP6, previously identified as androgen-dependent in the hamster epididymis in vivo. Examination of the material extracted from washed spermatozoa with 0.5 M-NaCl revealed the presence of radioactive proteins on spermatozoa. The zona-binding ability of spermatozoa from androgen-treated cultured proximal corpus tubules was significantly increased (P less than 0.001) as was the no. of spermatozoa/egg (5.51) compared with the value for control cultures (0.87 spermatozoa/egg). We suggest that androgen-dependent epididymal secretory proteins that associate with spermatozoa might participate in the formation or activation of a site for zona pellucida recognition in the sperm surface.

Animals↗
PubMed1984

Epididymal proteins mimic the androgenic effect on zona pellucida recognition by immature hamster spermatozoa.

The increase in zona pellucida binding caused by the exposure of cultured proximal corpus epididymidis to 2 microM-5 alpha-DHT (0.87 and 4.29 spermatozoa/egg for control and 5 alpha-DHT group respectively) was lost when 20 microM-cycloheximide was also added to the medium (0.72 spermatozoa/egg). These results were interpreted as meaning that de-novo protein synthesis was required to obtain the effect of androgens. When a fraction enriched in epididymal glycoproteins EP2-EP6 (18% total protein in epididymal cytosol and 30% in enriched fraction) and depleted of androgens (less than 120 pg testosterone + DHT/ml) was added to the cultured epididymal tubules, the zona pellucida-binding ability of the contained spermatozoa increased from 0.55 in controls to 2.73 spermatozoa/egg in the extract-treated group (P less than 0.02). When the enriched fraction was prepared from epididymides of 30-day castrates, the stimulatory effect was lost (1.04 spermatozoa/egg). We suggest that proteins synthesized in the epididymis are required to obtain the effect of androgens and that the glycoproteins EP2-EP6 may be involved.

Animals↗
PubMed1984

Addition of an androgen-free epididymal protein extract increases the ability of immature hamster spermatozoa to fertilize in vivo and in vitro.

The fertility of spermatozoa from the different epididymal segments of hamsters was tested by in-vivo insemination. Caput and proximal corpus spermatozoa were non-fertile; spermatozoa from the distal corpus epididymidis fertilized 13% (38/290) oocytes and those from the proximal and distal cauda epididymidis 71 and 87%, respectively. When tested by in-vitro insemination, distal corpus spermatozoa penetrated 44% of oocytes while those from the distal cauda fertilized 87% of oocytes. Spermatozoa from the distal corpus recovered in Medium BMOC fertilized 13% (28/219) of oocytes in vivo, while those mixed with an epididymal protein preparation (0.8 mg protein/ml) fertilized 24% (49/204; P less than 0.01) of oocytes. When distal corpus spermatozoa were inseminated in vivo with 0.8 mg epididymal protein preparation 34% (31/90) oocytes were fertilized and only 22% (23/103; P less than 0.05) oocytes were fertilized when the proteins were obtained from epididymides of animals castrated for 30 days. When distal corpus spermatozoa were preincubated for 5 h in medium without (control) or with protein preparation (0.8 or 1.6 mg protein/ml), a significant increase in in-vitro oocyte penetration was found (25 compared with 45%; P less than 0.05) when the protein was present at 1.6 mg/ml. These results confirm and extend previous observations suggesting a role for androgen-dependent glycoproteins secreted by the epididymis in the acquisition of fertilizing ability that occurs during sperm maturation.

Animals↗