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V Romano-Spica

Publications and source records attributed to V Romano-Spica.

At least 19 recordsLinked to original sources

Epidemiology of essential hypertension: the role of genetic polymorphism.

Over the past 20 years, the interest of the scientific community was increasingly placed in the field of genetic epidemiology and molecular genetics of blood pressure control. This paper explores references related to essential hypertension, gene and genetic epidemiology indexed in the MedLine health science database during the period 1980-2001. A systematic literature search was performed using selected keywords, such as 'genetic', 'genome' or a combination of words. We considered the study heading and evaluated the time profile of published articles. A total number of 3116 publications was collected and analyzed. Allelic distribution for the most studied polymorphisms of the renin-angiotensin system in different world populations was reviewed and reported together with a detection of their frequency in Italy: essential hypertensive patients (n = 90), healthy unrelated subjects (n = 300). Molecular variants at angiotensinogen (M and T), angiotensin II type 1 receptor (A and C) and angiotensin-converting enzyme (D and I) genes were analyzed by amplified fragment length polymorphism. A significant association was detected by chi2 analysis for angiotensinogen and angiotensin II-type I receptor allele distribution in hypertensive patients, in accordance with previous reports. Genetic data and methods are contributing more and more to epidemiological studies of complex diseases, and their application is influenced by information availability and Genome Project results.

Amplified Fragment Length Polymorphism Analysis↗

CCR5 and CCR2 gene polymorphisms in hypertensive patients.

Essential hypertension is a complex trait under polygenic control. Evidences suggests immune system involvement during pathogenesis. CC-chemokine receptor (CCR)5 and CCR2 are characterised by gene polymorphism. Variant alleles are derived from a deletion in the CCR5 gene (CCR5delta32) and a substitution mutation at the CCR2 locus (CCR264I). CCR polymorphic forms have been studied extensively as invasion cofactors for HIV-1, but they have also been implicated in immuno-related disorders. Here, we evaluate the allelic distribution of CCR5 and CCR2 genes in essential hypertension in a case-control study. Genotype frequency in a group of essential hypertensive patients (stage I-II; n=120) and a group of unrelated, healthy Caucasian subjects (n=340) is compared. CCR gene polymorphism is analysed by polymerase chain reaction and restriction enzyme digestion. A statistically significant difference was observed for CCR5 and CCR2 mutant alleles in essential hypertensive patients, compared with the controls (P=0.004 and P=0.003, respectively). CCR5delta32 and CCR264I alleles showed a 0.096 and 0.10 frequency among cases. To date, a role for the immune system in hypertension has not been clarified, nor has the predictive value of CCR polymorphisms.

Alleles↗

A molecular typing approach for evaluating bioaerosol exposure in wastewater treatment plant workers.

Bioaerosols associated with wastewater treatment process may represent a health risk for occupationally exposed personnel. To evaluate microbial contamination in plant workers, we compared oral cavity isolates against isolates collected from aerosol surrounding the aeration basin. Typing was performed by metabolic profile and arbitrarily primed-polymerase chain reaction. The latter is more sensitive and rapid than conventional tests. After comparison, isolates from the air samples were not related to those obtained from the exposed workers. This molecular approach can support bioaerosol risk evaluation .

Aerosols↗

AGT and AT1R gene polymorphism in hypertensive heart disease.

Left ventricular hypertrophy in patients with hypertension is a main clinical prognostic entity The aim of this study was to evaluate the association between mutations at genes of the renin-angiotensin system (RAS) and the development of left ventricular hypertrophy. Genetic polymorphism in angiotensinogen (AGT) and angiotensin Il-type 1 receptor (AT1R) genes was examined in a group of well-selected essential hypertensive caucasians with left ventricular involvement (n = 40) and a group of healthy unrelated caucasians (n = 150). Cardiac morphology and function were assessed by M-mode echocardiography. Molecular variants were analysed by amplified fragment length polymorphism. We observed a statistically significant difference both for AGT and AT1R genotype distribution in patients with left ventricular hypertrophy compared with controls (p<0.05). A 0.49 and 0.225 frequency was detected among cases for T and C mutant alleles at AGT and AT1R genes. Mutations in RAS genes are involved in the pathophysiology of target-organ damage in essential hypertension. Evaluation of molecular factors conferring a risk of developing heart involvement may lead to better identification of patient subgroups and more effective control of the clinical course.

Adult↗

A microwave-based method for nucleic acid isolation from environmental samples.

AIMS: A simple and rapid method was described for DNA isolation directly from activated sludge or other environmental sources, including soil and sediments. METHODS AND RESULTS: The present method is based on microwave thermal shock and provides DNA suitable for further analysis. It is also effective for RNA extraction. CONCLUSION: The protocol is effective, easy, fast and does not require the use of expensive equipment or reagents. SIGNIFICANCE AND IMPACT OF THE STUDY: The described method can be applied to difficult substrates in environmental microbiology studies.

DNA, Bacterial↗

Angiotensin-related genes involved in essential hypertension: allelic distribution in an Italian population sample.

BACKGROUND: Blood pressure is a quantitative multifactorial trait influenced by environmental and genetic determinants. Although several candidate genes have been associated with the development of essential hypertension, the mechanisms of individual susceptibility still remain unclear. Knowledge on the distribution of genetic polymorphisms in different populations is fundamental for the assessment of the predictive value of genetic variation. METHODS: We genotyped 300 healthy normotensive subjects from the Italian population for three polymorphisms, at the angiotensinogen (AGT, M and T), angiotensin II type 1 receptor (ATIR, A and C) and angiotensin-converting enzyme (ACE, D and I) genes. Polymorphisms were analyzed by polymerase chain reaction and restriction enzyme digestion. Statistical analysis was performed to verify the agreement with the Hardy-Weinberg equilibrium. RESULTS: The observed allelic distribution was in accordance with estimates reported for Caucasian populations. Variant allelic frequencies were 0.36 for the T and C alleles at the AGT andAT1R locus and 0.47 for the I allele of the ACE gene. AT1R and ACE genotype frequencies were in Hardy-Weinberg equilibrium, while there was a deviation of the AGT genotypes from those predicted by the equation. CONCLUSIONS: The studied polymorphisms are largely distributed in the Italian population sample, with a frequency of homozygous subjects for mutant alleles ranging from 9 to 22%. Epidemiology of mutations in the genes involved in blood pressure regulation provides tools to evaluate susceptibility to hypertension.

Adult↗

Allelic distribution of CCR5 and CCR2 genes in an Italian population sample.

Genetic polymorphisms of CCR5 and CCR2 human chemokine receptors have been associated with resistance during HIV-1 infection and disease progression. The protective effect of mutant alleles at these loci has important implications in AIDS pathogenesis. Chemokine receptors have a role in viral entry into target cells as well as in immune response modulation. In the present report, we studied the frequency of CCR5delta32 and CCR264I allelic variants among a representative sample of the Italian population. Observed allelic frequencies were 0.0454 and 0.0655, respectively. In both cases, genotype distribution was in equilibrium as predicted by the Hardy-Weinberg equation. Taken as a whole, about 21% of the population sample was found to be heterozygous for one or another of those two mutated alleles. Distribution of CCR5delta32 and CCR264I allelic variants within a population can be considered as a measure of genetic susceptibility to HIV infection and disease progression.

Alleles↗

Ets1 oncogene induction by ELF-modulated 50 MHz radiofrequency electromagnetic field.

We have analyzed gene expression in hemopoietic and testicular cell types after their exposure to 50 MHz radiofrequency (RF) non-ionizing radiation modulated (80%) with a 16 Hz frequency. The exposure system generates a 0.2 microT magnetic field parallel to the ground and a 60 V/m electric field orthogonal to the earth's magnetic field. Exposure conditions were selected so as to interfere with the calcium ion flow. Under these electromagnetic field (EMF) conditions, we observed an overexpression of the ets1 mRNA in Jurkat T-lymphoblastoid and Leydig TM3 cell lines. This effect was observed only in the presence of the 16 Hz modulation, corresponding to the resonance frequency for calcium ion with a DC magnetic field of 45.7 microT. We have also identified a putative candidate gene repressed after EMF exposure. The experimental model described in this paper may contribute to the understanding of the biological mechanisms involved in EMF effects.

Animals↗

A human placenta-specific ATP-binding cassette gene (ABCP) on chromosome 4q22 that is involved in multidrug resistance.

We characterized a new human ATP-binding cassette (ABC) transporter gene that is highly expressed in the placenta. The gene, ABCP, produces two transcripts that differ at the 5' end and encode the same 655-amino acid protein. The predicted protein is closely related to the Drosophila white and yeast ADP1 genes and is a member of a subfamily that includes several multidrug resistance transporters. ABCP, white, and ADP1 all have a single ATP-binding domain at the NH2 terminus and a single COOH-terminal set of transmembrane segments. ABCP maps to human chromosome 4q22, between the markers D4S2462 and D4S1557, and the murine gene (Abcp) is located on chromosome 6 28-29 cM from the centromere. ABCP defines a new syntenic segment between human chromosome 4 and mouse chromosome 6. The abundant expression of this gene in the placenta suggests that the protein product has an important role in transport of specific molecule(s) into or out of this tissue.

ATP-Binding Cassette Transporters↗

Isolation and characterization of a novel gene expressed in multiple cancers.

Using differential display method, we have isolated and characterized a novel gene, N8, encoding an approximately 24 kDa protein. It is located on human chromosome 8q13 region. N8 gene is expressed at high levels in tumor derived cell lines from multiple cancers. It is also expressed at higher levels in lung tumors than normal lung tissue. N8 is also differentially expressed in fetal and adult tissues. In adult, N8 is expressed at high levels in brain, kidney, prostate, pancreas and intestine and at very low levels in lung, liver, hematopoietic cells and gonads. During murine embryonic development N8 is expressed in the epithelium of the intestine, stomach, olfactory epithelium, neuronal layers of retina, kidney and salivary gland. Taken together, these results suggest that N8 may play different roles during embryogenesis and in the adult animals.

Amino Acid Sequence↗

ETS1 suppresses tumorigenicity of human colon cancer cells.

We have ectopically expressed transcription factor ETS1 in two different highly tumorigenic human colon cancer cell lines, DLD-1 and HCT116, that do not express endogenous ETS1 protein and have obtained several independent clones. The expression of wild-type ETS1 protein in these colon cancer cells reverses the transformed phenotype and tumorigenicity in a dose-dependent manner. By contrast, expression in DLD-1 cells of a variant form of ETS1, lacking transcriptional activity, did not alter the tumorigenic properties of the cells, suggesting that the reduction in tumorigenicity in these clones was specific for the wild-type ETS1 gene products. Since these colon cancer cells have multiple genetic alterations, the system described in this paper could be a good model to study the suppression of tumorigenicity at a transcriptional level, which could lead to the design and development of novel drugs for cancer treatment.

Base Sequence↗

Role of ETS1 in IL-2 gene expression.

The ETS1 gene encodes a sequence-specific transcription factor binding to purine-rich DNA sequences (-GGAA-) present in the transcriptional regulatory regions of many cellular and viral promoters/enhancers, including many lymphokine genes. The ETS1 gene is expressed at high levels in resting T cells and at very low levels after T cell activation, suggesting it may suppress the expression of genes induced during T cell activation. To find out if ETS1 regulates expression of the IL-2 gene, we have ectopically expressed antisense (AS) ETS1 in Jurkat T cells to block the formation of ETS1 proteins. AS ETS1 transfectants produce higher levels of IL-2 compared with sense ETS1 transfectants. Expression of ETS1 DNA binding domain in Jurkat T cells also decreased the production of IL-2. In AS ETS1 transfectants, IL-2 formation was completely inhibited by cyclosporin A and FK590. The IL-2 promoter linked to a chloramphenicol acetyl transferase reporter gene has high activity in AS ETS1 transfectants, indicating that increased IL-2 production seems to be a result of transcriptional induction. Taken together, these results suggest the possibility that ETS1 may act as a negative regulator of IL-2 gene transcription and provide a rational approach toward engineering the endogenous expression of IL-2 in T cells.

Cell Line↗

Epitope mapping of human ETS1 monoclonal antibody.

The epitope for E44 monoclonal antibody (mAb) was mapped using mutated ETS1 proteins lacking different carboxy-terminal regions and by the employment of synthetic oligopeptides spanning the epitope region. This epitope lies around Arg211 of the human ETS1 protein since substitution of Arg211 by Gln211 in the epitope region results in the loss of recognition of the mouse ETS1 protein by E44 mAb. Substitution of Leu214 by valine214 in the epitope region (as is found in the chicken ETS1 and viral Ets proteins) does not alter the capacity of the E44 mAb to recognize this antigen. Taken together, these results suggest that a specific ionic interaction is able to play a pivotal role in the recognition of the ETS1 protein by the E44 mAb.

Amino Acid Sequence↗

Cytostatic drugs and health risks for exposed personnel: search for new biomarkers.

The use of antiblastic drugs has opened up new perspectives in improvement of therapy and life quality for cancer patients. The widespread clinical application of cytostatic drugs implies risks for exposed hospital personnel, due to genotoxic and toxic-reproductive effects. Biological monitoring is fundamental to identify individuals at risk but is limited by the long latency of chronic effects, absence of unique cellular targets and low sensitivity of available laboratory tests. The objective of this study was to investigate toxic mechanisms by a molecular biology approach, searching for biomarkers potentially useful in monitoring programs. The proposed experimental model consisted of cell line exposure to cyclophosphamide, an alkylating agent of wide clinical use. Cellular response has been investigated focusing on potential targets at RNA level, through reverse transcription polymerase chain reaction (RT-PCR) and differential display analysis. We studied the expression of several genes involved in differentiation, apoptosis and chemoresistance: ets1, bax, bcl-2, bag-1, bcl-X, mdr1 and mrp. Specific patterns of mRNA modulations were observed. Differential display analysis revealed candidate genes induced or repressed following exposure: their characterization is in progress. Besides improving the understanding of toxic mechanisms, identification of modulated molecular targets opens up new perspectives in exposure risk assessment, biomonitoring and preventive strategies at occupational level.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Hepatitis C virus infection: other biological fluids than blood may be responsible for intrafamilial spread.

BACKGROUND/AIMS: Several epidemiological studies have shown the existence of other routes of transmission of the hepatitis C virus besides the parenteral one, but the mechanisms involved are not yet understood. The general aim of this study was to evaluate the prevalence of hepatitis C virus infection in family contacts of infected patients and to analyze the possible risk factors and alternative transmission routes. METHODOLOGY: One hundred and thirty-eight relatives of 45 patients (index cases) affected by C virus-related chronic hepatitis were studied. The relatives were 45 spouses, 89 children and 4 cohabitants who underwent detection of serum anti-HCV antibodies; the anti-HCV-positive subjects were tested for serum HCV-RNA. The index cases, all the spouses and only other infected relatives were tested for the presence of HCV-RNA in saliva RESULTS: Antibodies to hepatitis C virus were detected in 5.7% of the family members while 11.1% of the analyzed spouses were serum HCV-RNA-positive. HCV-RNA was found in 44% of the examined saliva and 39% of these were found serum HCV-RNA-negative. The prevalence of hepatitis C virus among household contacts, excluding cases with previous parenteral exposure, was 3.6%. CONCLUSIONS: The epidemiological data on the intrafamilial spread of hepatitis C virus may be underestimated owing to the existence of infected relatives serum-negative but saliva-positive for the presence of the virus. The whole of these observations suggests a possible role of biological fluids in intrafamilial spread of hepatitis C virus.

Adult↗