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M Salis

Publications and source records attributed to M Salis.

17 recordsLinked to original sources

HLA phenotype and haplotype frequencies in Sardinia (Italy).

The gene and haplotype frequencies of the HLA-A, B, Cw, DR and DQ loci were determined in two Sardinian samples from the Nuoro (N = 252) and Sassari (N = 153) districts. Our data were compared with those reported for other Italian, European and Mediterranean populations and previously studied Sardinian samples. The results showed that the two samples differ from other Italian and European populations in the frequencies of many alleles and haplotypes. For example in the A2, B18, Cw5 and DR3 allele frequencies and the A1-B8, A2-B17, A3-B7, A30-B18, A2-Cw7, A30-Cw5, A30-DR3, A32-DR2, Cw5-DR3 and Cw7-DR4 haplotype frequencies. In common with the Mediterranean populations, Sardinians, too, have a limited number of haplotypes with significant linkage disequilibrium. The results revealed, therefore, significant genetic differentiation between Sardinians and other European and Mediterranean populations, confirming the genetic peculiarity of the Sardinians.

Ethnicity↗

Amplification of the Xq28 FRAXE repeats: extreme phenotype variability?

We report on a new case of FRAXE mutation identified through the screening of a population of FRAXA-negative mentally retarded individuals. The index case, a 4-year-old boy with distinct minor anomalies and mental retardation with severe verbal impairment, his older brother, referred to as normal, and the mother have undergone careful clinical and molecular evaluation. The molecular defect, characterized by standard Southern blot analysis, is represented by a hypermethylated "full mutation" in the 2 boys and by a unique, altered, presumably unmethylated, band in the mother, which is interpreted as a "premutation." The cytogenetic analysis failed to detect a folate-sensitive Xq27-28 fragile site in either "fully mutated" individual. The phenotype and intellectual performance of the 15-year-old brother of the propositus appeared completely normal. Our propositus shares some traits with previously described FRAXE-mutated subjects, suggesting an association with the Xq28 molecular defect; nevertheless, we find it difficult to reconcile the molecular identity and phenotypic difference in these mutated members of the same family. This could be a case of extreme phenotypic variability or a result of a more complicated molecular mechanism.

Blotting, Southern↗

Study of the matrimonial structure of the population of central Sardinia (Italy).

Temporal changes in the matrimonial structure of four Sardinian populations (Bitti, Lula, Lodè and Gavoi) have been studied. The endogamy rates and the average marriage distances indicate that the four villages experienced a long period of isolation. Only in recent decades endogamous marriages have fallen shortly. The trends of marital isonymy and inbreeding, evaluated both from isonymy and dispensation for consanguineous marriages, are similar to those of endogamy. The kinship values between pairs of populations show some preferential relationship (Bitti-Lodè, Lodè-Lula) and an evident differentiation between Gavoi and Bitti. The results also indicate that the values of kinship are not associated with the geographic distances. The possible impact of the matrimonial structure on the genetic structure and the relationships among the studied populations will be examined in further investigations, in which the genetic markers will be considered.

Adult↗

Genetic data on Alghero population (Sardinia): contrast between biological and cultural evidence.

Data on 20 genetic polymorphisms (61 alleles) in the Algehero population on the northwestern coast of Sardinia are presented and discussed in relation to its linguistic peculiarity inside the island. Since the Aragonese (Spain) conquest of Sardinia in the 13th century, the Catalan language, the same as that spoken in Northeastern Spain and certain districts of Southern France, has been used in Alghero even until today. Analysis for heterogeneity of gene frequency distributions indicates that the genetic information obtained on Alghero is adequate to discriminate Sardinians from other neighbouring populations. Genetic variation between populations measured through genetic distances and principal-component analysis shows that the present-day population of Alghero is much closer genetically to Sardinians than to Catalonians. Our genetic results do not support any interpretation of the linguistic affinities between Alghero and Catalonia at present as indicative of biological kinship.

Alleles↗

Blood groups of the Sardinian population (Italy).

The genetic polymorphism of eight red cell blood group systems was examined in a population sample from Sardinia (Italy). The Sardinian frequencies of most of the examined genes were found out the range of Italian populations. Relationships among Italian and other Mediterranean populations were examined by principal component analysis. This kind of analysis confirms the genetic peculiarity of the Sardinian population.

Adult↗

Stress and beta-carbolines decrease the density of low affinity GABA binding sites; an effect reversed by diazepam.

Cerebral cortex membranes from rats habituated to manipulations preceding decapitation (habituated rats) had 40% higher GABA binding than membranes from naive animals. Diazepam (5 X 10(-6) M), added to membranes from naive rats, increased GABA binding to the level of habituated rats, but failed to induce any further increase in membranes from the latter animals. Vice versa, beta-carbolines (FG 7142, beta-CCE, DMCM) added to membranes from habituated rats lowered GABA binding to the level of naive animals, but caused no further decrease in the membranes from this last group. Diazepam removed the effect of beta-carbolines in membranes from habituated rats. It is suggested that handling represents a stressful stimulus for naive animals and that stress lowers GABA binding by releasing an endogenous ligand for benzodiazepine receptors possessing similar properties to beta-carbolines. Finally, the results indicate that the emotional status of animals from which brain tissue is obtained should be considered when connections between GABA and benzodiazepine receptors are studied.

Animals↗

Evidence for an involvement of GABA receptors in the mediation of the proconvulsant action of ethyl-beta-carboline-3-carboxylate.

The kinetic characteristics of binding of [3H]-GABA and the pattern of isoniazid-induced convulsions were studied in rats treated with repeated intraventricular injections of ethyl-beta-carboline-3-carboxylate (beta-CCE) (10 micrograms/rat, twice daily for 8 days). Thirty-six hours after the last injection, the total number of binding sites for [3H]-GABA was decreased (25%) in the cerebral cortex and hippocampus. On the other hand, there was no significant difference in the dissociation constant (KD) between beta-CCE and solvent-treated rats. The decrease in binding sites for [3H]-GABA was paralleled by a strong potentiation of the convulsant pattern elicited by isoniazid. The results suggest that the proconvulsant effect elicited by beta-CCE is mediated by the decrease in the total number of binding sites for GABA, secondary to the interaction between beta-CCE and the benzodiazepine receptor coupled to the GABA receptor.

Animals↗

Increase of cyclic GMP in cerebellum by methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM).

The intraperitoneal administration of DMCM (0.5-3 mg/kg) produced a dose-related increase in the content of cyclic GMP in the rat cerebellar cortex. The effect of DMCM on cyclic GMP was abolished by pretreatment with benzodiazepine receptor ligands, diazepam and Ro15-1788 and by the GABA agonist muscimol. The results suggest that DMCM increases cerebellar cyclic GMP content through a direct action on benzodiazepine receptors located in the cerebellar cortex. The interaction between DMCM and the GABAergic system associated with benzodiazepine receptors is discussed. Cerebellar cyclic GMP content can be used as a biochemical index to differentiate agonists and antagonists for benzodiazepine receptors.

Animals↗

Effect of a vitamin A-free diet on [3H]diazepam and [3H]GABA binding in the rat retina.

Benzodiazepine and GABA binding sites in the rat retina are influenced by a vitamin A-free diet. In rats fed a vitamin A-free diet, the total number of [3H]GABA and [3H]diazepam binding sites was markedly higher than in rats given a balanced diet. No differences were found in the apparent affinities of [3H]GABA and [3H]diazepam for their specific binding sites. The results suggest that GABA and benzodiazepine binding sites have a role in the function of the retina.

Animals↗

Brain benzodiazepine receptors increase after chronic ethyl-beta-carboline-3-carboxylate.

Rats were treated with repeated intraventricular injections of ethyl-beta-carboline-3-carboxylate (beta-CCE) (10 micrograms/rat, twice daily for 8 days), 36 h after the last injection, the total number of 3H-diazepam binding sites was increased in the cerebral cortex, cerebellum and hippocampus by 63, 51 and 38%, respectively. On the other hand, there were no significant differences in the dissociation constants (KD) between beta-CCE and solvent treated rats. In contrast, chronic beta-CCE administration failed to change the number of the apparent affinity of 3H-beta-CCE binding sites in all the brain areas examined. The results suggest that beta-CCE is an antagonist at the 3H-diazepam binding sites.

Animals↗

Biochemical changes in the rat cerebellar cortex elicited by chronic treatment with methyl mercury.

Long-term (20 days) treatment with methyl mercury (MeHg) increases the total number of benzodiazepine binding sites and decreases essentially the content of cyclic GMP in the cerebellar cortex. In contrast, this treatment fails to modify the content of GABA and cyclic AMP, GAD activity and GABA binding sites in the same brain area. The changes in cyclic GMP and benzodiazepine binding sites in the cerebellar cortex are discussed in relation to the motor disturbances associated with MeHg intoxication.

Animals↗

Age-related changes of benzodiazepine and GABA binding sites in the rat retina.

The changes in the number and sensitivity of benzodiazepine and GABA binding sites in the rat retina during postnatal development, adulthood and ageing and their functional relationship at different ages have been studied. Data indicate an increase in the total number of both GABA and benzodiazepine binding sites with age. In contrast, the activation of retinal benzodiazepine receptor binding by GABA is significantly reduced in aged rats with respect to young adult and newborn rats. Moreover, the activation of retinal benzodiazepine receptor binding induced by dark exposure of the animals is present in young adult rats but is lost in aged rats. These results suggest that in the retina of aged rats there is an increase of GABA and benzodiazepine receptors which have lost their functional connection.

Aging↗

[The assessment of exposure to the risk of the manual lifting of patients and the results of clinical studies in the hospitals of Bolzano and Bressanone].

A study was made in two hospitals in the province of Bolzano in order to ascertain the possible relationship between risk due to manual lifting of patients and occurrence of back disorders in healthcare workers. Risk analysis was carried out in 16 wards, with 207 workers assessed by means of clinical/anamnestic check-up of the spine. In the majority of the wards analysed the index of exposure to patient lifting was average or high due mainly to the lack of equipment, unsatisfactory structures and furnishings, and organizational factors. This was particularly evident in the Bressanone hospital where there were fewer workers to each department. As regards the clinical assessment of the spine, from the overall analysis of the results it was seen that in the hospital in Bressanone the prevalence of degenerative disorders of the lumbosacral region of the spine was 3.9% and in the Bolzano hospital it was 5.7%. Similar differences were observed in the prevalences of episodes of acute low back pain reported in the previous 12 months: Bressanone 7.7%, Bolzano 3.8%. In both hospitals 3rd grade SAP was diagnosed in about 5% of the subjects examined and globally clinical/functional alterations of the lumbar spine were observed in 20% of the Bressanone workers and in 27.2% of the Bolzano workers. Management of the cases judged unfit for manual lifting of patients was particularly difficult because of the high percentage of such cases (8-9%). On the basis of these results, the administrations of both hospitals undertook a series of short-, medium- and long-term interventions in order to reduce the risk for the spine.

Adolescent↗

[A training experience for hospital workers employed in the manual lifting of loads (Bressanone Hospital): its contents and the verification of efficacy].

A check-up of the efficacy of training in the specific field of disabled patient handling was made in the Bressanone Hospital. Some members of the staff had been previously trained in this subject and afterwards they organized courses for all the staff engaged in patient assistance. Before and after this course a series of parameters were recorded on appropriate cards, that enabled a comparison to be made of the various positions assumed by the workers during patient handling, with a concise assessment made for each manoeuvre. Altogether 80 manoeuvres were studied in the medical departments, 40 before and 40 six months after the training course. The results obtained were not up to expectations even though on the whole the number of manoeuvres judged totally incorrect was reduced considerably from 43% to 15%. This was due to a lack of coordination in the action plan drawn up for improvement of this risk factor and especially to failure to purchase equipment (for raising patients, minor aids and wheelchairs). It is stressed that training of health care staff on the topic of risk factors present in hospital environments must be considered as a part of hospital management strategy and therefore developed according to well defined programmes and methods.

Adolescent↗