Search PubMed⌕ Search

Biomedical subjects

G Neri

Publications and source records attributed to G Neri.

At least 397 records · Page 22Linked to original sources

Gene for non-specific X-linked mental retardation maps in the pericentromeric region.

Linkage analysis was carried out in a large four-generation German family segregating for non-specific X-linked mental retardation. Affected males have moderate intellectual handicap. Speech delay, deviant behaviour, and hyperactivity have also been reported. Head circumference and testicular volumes are normal. Cytogenetic analysis failed to show evidence for fragile site or structural abnormality of the X chromosome. None of the obligatory carriers shows any clinical symptoms. Close linkage without recombination (lod scores 1.74 to 2.05) has been found between the disease locus (MRX1) and the polymorphic DNA loci DXS7 (Xp11.4-p11.3), MAOA (Xp11.3-p11.23), DXS255 (Xp11.22), and DXS159 (Xq12) suggesting that the gene responsible for the disease in this family maps in the pericentromeric region of the X chromosome. Linkage data obtained with the flanking marker loci OTC (Xp21.1) and DXS95 (Xq21.2-q21.3) also were compatible with this localization of the MRX1 gene. Close linkage to loci from Xp22, Xq22, Xq24-25, or Xq28 could be excluded.

Adult↗

X-linked mental retardation with marfanoid habitus: first report of four Italian patients.

We report on 4 new cases of mildly retarded patients with marfanoid habitus and a characteristic constellation of minor anomalies. These patients, although sporadic, are likely to be affected by the same X-linked type of mental retardation described by Lujan et al. (American Journal of Medical Genetics 17:311-322, 1984) and more recently by Fryns and Buttiens (American Journal of Medical Genetics 28:267-274, 1987). The similar psychiatric history in 2 of our patients suggests that psychotic behaviour could be an additional manifestation, previously unrecognized in this condition. Late diagnosis of this relatively new syndrome in all our patients confirms the difficulty of the nosologic definition of mentally retarded individuals on clinical grounds alone. On the other hand, the Lujan-Fryns syndrome appears to be more common than one would have thought.

Abnormalities, Multiple↗

XLMR genes: update 1992.

Up to now, we have identified 77 X-linked conditions in which mental retardation is the primary or a major component manifestation. These conditions were subdivided into 2 categories, designated respectively "X-linked mental retardation syndromes" and "Non-specific X-linked mental retardation". Forty genes have been regionally mapped onto the X chromosome. However, in several instances the data were derived from a single family and most lod scores were less than 3.0.

Chromosome Mapping↗

New XLMR syndrome with characteristic face, hypogenitalism, congenital hypotonia and pachygyria.

A previously unreported X-linked MCA/MR syndrome is described in 4 members of a large family. Phenotypic manifestations include mental retardation, microcephaly, failure to thrive, severe congenital hypotonia, characteristic face, hypogenitalism, pachygyria. This appears to be an X-linked dominant trait with decreased penetrance and expressivity in carrier females.

Adolescent↗

Skin biopsy of Mediterranean cetaceans for the investigation of interspecies susceptibility to xenobiotic contaminants.

Various studies on Mediterranean cetaceans have revealed bioaccumulation of contaminants such as organochlorines (OCs) and heavy metals. The susceptibility of these animals to organic pollutants and the relationship between bioaccumulation and population decline (as in the case of Delphinus delphis) are unexplored fields. In this study, we used a non-destructive approach (skin biopsy) to explore OC bioaccumulation processes and mixed-function oxidase activity (BPMO) in four species of cetaceans: striped dolphin (Stenella coeruleoalba), bottlenose dolphin (Tursiops truncatus), common dolphin (D. delphis) and fin whale (Balaenoptera physalus). Significant differences in BPMO induction and OC levels were found between odontocetes and mysticetes, the former having mixed-function oxidase activities four times higher than the latter, binding with levels of OCs one order of magnitude higher in odontocetes. A significant correlation (P < 0.05) between BPMO activities and OC levels was found in B. physalus. In an ongoing project, fibroblast cultures have been used as an alternative in vitro method of evaluating interspecies susceptibility to contaminants such as OCs and polycyclic aromatic hydrocarbons (PAHs). These results suggest that cetacean skin biopsies are a powerful non-invasive tool for assessing ecotoxicological risk to Mediterranean marine mammals species.

Animals↗

Skin biopsies for cell cultures from Mediterranean free-ranging cetaceans.

The aim of this study was to develop a useful method for obtaining viable tissue samples for establishing cell cultures from skin biopsies of free-ranging cetaceans. The skin biopsies were performed by two methods: dart from an air gun and dart from a crossbow. The dart tip was modified to collect tissue. The tissue was kept in tissue culture medium at ambient temperature, then processed within 24 h. Many modifications in culture technique, with respect to conventional culture methods for human fibroblasts, were made. The cultures thus obtained can be used for many purposes, including genetic and toxicological studies. In toxicology they are an alternative in vitro system for studying threatened animals such as marine mammals. In particular, fibroblasts can be used to test the vulnerability of cetaceans and pinnipeds to different environmental contaminants such as organochlorine compounds, heavy metals and polycyclic aromatic hydrocarbons.

Animals↗

Multi-trial biomarker approach in Meganyctiphanes norvegica: a potential early indicator of health status of the Mediterranean "whale sanctuary.".

The aim of this study was to propose a suite of biomarkers (BPMO activity, NADPH-cytocrome c reductase, NADH-ferricyanide reductase. esterases, porphyrins, vitellogenin and zona radiata proteins) and residue levels (organochlorines, PAHs and heavy metals) in the zooplanktonic euphausiid Meganyctiphanes norvegica as a potential multi-disciplinary diagnostic tool for assessment of the health status of the Mediterranean "whale sanctuary". Very little difference in BPMO was detected between sites, with values ranging from 0.75 to 2.68 U.A.F./mg prot/h. On the other hand larger differences between sites were found for reductase activities. Esterases (AChE), porphyrins (Copro-, Uro-, Proto-porphyrins) vitellogenin and zona radiata proteins were also detectable in this zooplanctonic species. Hg showed mean levels of 0.141 ppm d.w., Cd 0.119 ppm d.w. and Pb 0.496 ppm d.w. Total PAHs ranged from 860.7 to 5,037.9 ng/g d.w., carcinogenic PAHs from 40.3 to 141.7 ng/g d.w., HCB from 3.5 to 11.6 ng/g d.w., DDTs from 45.3 to 163.2 ng/g d.w. and the PCBs from 84.6 to 210.2 ng/g d.w.

Animals↗

Biomarkers for endocrine disruptors in three species of Mediterranean large pelagic fish.

The hypothesis that Mediterranean top predator species, such as large pelagic fish, are potentially at risk due to endocrine disrupting chemicals (EDCs), is investigated. The potential estrogenic effects of PHAHs in three fish species of commercial interest, the top predators bluefin tuna (Thunnus thynnus thynnus), swordfish (Xiphias gladius), and Mediterranean spearfish (Tetrapturus belone), were investigated using vitellogenin (Vtg), zona radiata proteins (Zrp) and mixed function oxidases (EROD, BPMO) as diagnostic tools. High induction of Vtg and Zrp was detected by western blot and ELISA techniques in adult males of X. gladius and T. thynnus thynnus, suggesting that these species are at high toxicological risk in the Mediterranean sea. Comparison of BPMO and EROD activities in the three species indicated, both in male and female, much higher MFO activity in bluefin tuna. This data suggests high exposure of this species to lipophilic xenobiotic contaminants in the Mediterranean environment.

Animals↗

Pharmacological reactivation of inactive genes: the fragile X experience.

The present review on the pharmacological reactivation of inactive genes focuses on our experience with the fragile X syndrome. The fragile X syndrome of mental retardation is the prototype of a series of inherited neurological disorders caused by abnormal expansion of repeated trinucleotide sequences embedded in various genes. In a number of these disorders, such as Huntington disease and several forms of spinocerebellar ataxias, the expanded CAG repeat is translated, resulting in a polyglutamine-containing protein that indirectly causes neurodegeneration. On the contrary, in the fragile X syndrome, the expanded CGG repeat is contained in the regulatory region of the FMR1 gene and causes transcriptional inactivation. The mutation spares the coding region of the FMR1 gene, which potentially would allow synthesis of a normal protein if transcription could be restored. This prompted us to try and reactivate the gene function with different pharmacological regimens. We discuss our successful results with DNA demethylating and histone hyperacetylating drugs and their implications for future treatments of the fragile X syndrome.

Antineoplastic Agents↗

Effect of luteinizing hormone-releasing hormone on rat adrenocortical cells.

The effects of luteinizing hormone-releasing hormone (LH-RH) on the function of rat adrenal cortex were investigated by using dispersed zona glomerulosa (capsular) and zona fasciculata-reticularis (inner) cells. LH-RH increased basal (but not adrenocorticotropic hormone (ACTH)-stimulated) corticosterone secretion of inner cells, without affecting either aldosterone or corticosterone production by capsular cells. LH-RH markedly raised basal (but not ACTH-enhanced) cyclic-AMP release by inner cells. The corticosterone secretagogue action of LH-RH was abolished by the protein kinase A inhibitor H-89. The conclusion is drawn that LH-RH specifically stimulates adrenal glucocorticoid secretion in rats through the activation of the adenylate cyclase signaling pathway.

Adrenal Cortex↗

[A three-year long follow-up of a group of "everyday patients" in a mental health center].

OBJECTIVE: This research concerns those patients who most attend the community Mental Health Centre (CSM), hereby called "everyday patients". According to a previous research (Pileggi et al., 1992) a sample of patients mostly attending the Centre had been pointed out. Basing on the number of attendances, it emerged that some of those patients (57) had been on the average attending the Centre more than twice a week and, despite being only 10% of the total number of users, they had taken on a large share of the services offered by the Centre (30%). Therefore, those patients were the ones the Centre had been working for more intensely and continuously. Three years later, the object of this research is to check the assistance and clinical destiny of such patients and compare their patterns of attendances to those ones regarding the remainder of the CSM users. The hypothesis is that "everyday patients" are assisted by different and continuous treatments and that such a procedure prevents patients from dropping out and determines a strong reduction in relapses and less frequent attendances. DESIGN: Longitudinal study on a 42 patient sample (19 males, 23 females) on therapy at CSM. SETTING: Mental Health Centre, "Saragozza" District, Sanitary Unit of Bologna. MAIN OUTCOME MEASURES: The following elements have been examined: 1) social and demographic features; 2) duration of psychiatric history; 3) clinical diagnosis according to DSM-III-R, set by patients personal psychiatrist; 4) global functioning level as examined by two psychiatrists or psychologists from the Centre, using DSM-III-R Global Functioning Scale (GFS); 5) actions carried out and patterns of using the CSM services over the past 12 months. Concordance measures among independent examiners (Cohen K) and non-parametric variability measures for comparison between groups (Chi-square and Kruskal-Wallis tests) have been used. RESULTS AND CONCLUSION: Results partially confirm the original hypotheses. In particular, complicated services (psychological and pharmacological therapies and rehabilitation) are carried out for the most of "everyday patients" and much more intensely to them than to the remainder of the users. No drop-out has been found out, the global functioning level of the patients is good in most of cases and the number of necessary admissions to psychiatric wards has been reduced. However, the "attendance share" relevant to the sample of "everyday patients" is still high compared to the total number of the CSM users. Besides, discharge rate is nought.

Adult↗

[Quality of life assessment: validation of the Italian version of the WHOQOL-Brief].

OBJECTIVE: To test the psychometric properties of the Italian version of the WHOQOL-BRIEF (e.g., construct and internal validity, concurrent validity with the MOS SF-36 and test-retest reliability). The WHOQOL-BRIEF is a 26-items self-report instrument which assesses four domains assumed to represent the Quality Of Life (QOL) construct: physical domain, psychological domain, social relationships domain and environment domain, plus two facets for assessing overall QOL and general health. METHODS: Data have been collected in three sites (Bologna, Modena and Padua), located in the North of Italy, in the framework of the international WHOQOL project. According to the study design, the sample had to include about 50% males and 50% females, 50% of subjects below and 50% above the age of 45, all in contact with various health services. A subsample has been re-interviewed after 2-3 weeks in order to study test-retest reliability. After the WHOQOL-BRIEF, most subjects have also been administered the MOS-SF36 in order to test the concurrent validity between these two instruments. RESULTS: The instrument was administered to 379 subjects (1/6 healthy and 1/6 sick), chosen to be representative of a variety of different medical conditions. Seventy patients, who displayed stable health conditions, have been reassessed after 2-3 weeks to study test-retest reliability. The WHOQOL-BRIEF domains has shown good internal consistency, ranging from 0.65 for the social relationships domain to 0.80 for the physical domain; it has been able to discriminate between in- and out-patients and between the two age groups considered in the present study (< 45, > or = 45 years). Only physical and psychological domains were found to discriminate between healthy and ill subjects. No gender differences in the mean scores for the four domains were found. Concurrent validity between the WHOQOL-Brief and the MOS-SF-36 was satisfactory, and specific for the physical and psychological health domains. Test-retest reliability values were also good, ranging from 0.76 for the environment domain to 0.93 for the psychological domain. CONCLUSIONS: This study shows that the WHOQOL-BRIEF is psychometrically valid and reliable, and that it is also potentially useful in discriminating between subjects with different health conditions in clinical settings.

Aged↗

Mosaic trisomy 17 in amniocytes: phenotypic outcome, tissue distribution, and uniparental disomy studies.

Mosaicism for trisomy 17 in amniocyte cultures is a rare finding, whilst postnatal cases are exceptional. In order to gain insight into the possible effects of the distribution of the trisomic line and of uniparental disomy (UPD) on embryofoetal development, we have performed follow-up clinical, cytogenetic and molecular investigations into three newly detected prenatal cases of trisomy 17 mosaicism identified in cultured amniotic fluid. In the first case, the pregnancy ended normally with the birth of a healthy girl, and analysis of newborn lymphocytes and of multiple extra-embryonic tissues was indicative of confined placental mosaicism. The second case was also associated with a normal pregnancy outcome and postnatal development, and only euploid cells were found in peripheral blood after birth. However, maternal isodisomy 17 consequent to a meiosis II error and loss of a chromosome 17 homologue was detected in peripheral lymphocytes postnatally. In the third case, pathological examination after termination of pregnancy showed growth retardation and minor dysmorphisms, and the trisomic line was detected in foetal skin fibroblasts. In addition, biparental derivation of chromosome 17 was demonstrated in the euploid lineage. These results, together with previously reported data, indicate that true amniotic trisomy 17 mosaicism is more commonly of extra-embryonic origin and associated with normal foetal development. Phenotypic consequences may arise when the trisomic line is present in foetal tissues. Case 2 also represents the first observation of maternal UPD involving chromosome 17; the absence of phenotypic anomalies in the child suggests that chromosome 17 is not likely to be subject to imprinting in maternal gametes.

Adult↗

Prolonged cerebellin administration inhibits the growth, but enhances steroidogenic capacity of rat adrenal cortex.

Cerebellin is a 16-amino acid peptide, that has been previously found to acutely stimulate steroid secretion from rat adrenal cortex in vivo and in vitro. We have investigated the effects of a prolonged cerebellin treatment (daily injections of 15 nmoles/kg for 6 consecutive days) on the growth and secretion of rat adrenal cortex. Cerebellin lowered adrenal weight, and morphometry showed that this was due to the decrease in the volume of each adrenocortical zone exclusively ensuing from the reduction in the number of its parenchymal cells. Cerebellin did not alter plasma concentration of ACTH, but it raised the levels of circulating aldosterone and corticosterone. The conclusion is drawn that cerebellin chronic administration evokes a marked hypoplastic atrophy of rat adrenocortical cells, that is coupled with an enhanced ACTH-independent steroidogenic capacity of the remaining parenchymal cells.

Adrenal Cortex↗

Genetic counseling in hereditary non-polyposis colorectal cancer.

Genetic counseling is a medical process aimed at providing information about disease risks for hereditary conditions. For adult-onset diseases, such as cancer, the main purpose consists in formulating probability estimates of disease appearance, along with details on preventive or follow-up measures. The process of genetic counseling has been substantially modified by the availability of molecular tests to identify mutant gene carriers. So far, 16 autosomal dominant genes associated with cancer susceptibility have been cloned. Four of these, which encode for components of the DNA mismatch repair machinery, have been implicated in hereditary non-polyposis colorectal cancer, one of the most common hereditary cancer syndromes. Genetic counseling and testing in hereditary non-polyposis colorectal cancer is associated with several problems that are common to other hereditary conditions (psychologic consequences, confidentiality, genetic "discrimination", testing of minors, prenatal diagnosis) and peculiar to the specific condition (incomplete penetrance, genotypic and phenotypic heterogeneity, limits of currently available tests). For such reasons, genetic testing should be performed in qualified research laboratories and restricted to highly selected families. In this way, pilot studies, involving both clinicians and researchers, can be undertaken with the aim of providing comprehensive results, potentially applicable to other cancer-predisposing conditions.

Colorectal Neoplasms, Hereditary Nonpolyposis↗