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.

Adapted Physical Activity for the Promotion of Health and the Prevention of Multifactorial Chronic Diseases: the Erice Charter

The Erice Charter was unanimously approved at the conclusion of the 47th Residential Course "Adapted Physical Activity in Sport, Wellness and Fitness: New Challenges for Prevention and Health Promotion", held on 20-24 April 2015 in Erice, Italy, at the "Ettore Majorana" Foundation and Centre for Scientific Culture, and promoted by the International School of Epidemiology and Preventive Medicine "G. D'Alessandro" and the Study Group on Movement Sciences for Health of the Italian Society of Hygiene, Preventive Medicine and Public Health. After an intense discussion the participants identified the main points associated with the relevance of physical activity for Public Health, claiming the pivotal role of the Department of Prevention in coordinating and managing preventive actions. The participants underlined the importance of the physicians specialized in Hygiene, Preventive Medicine and Public Health. The contribution of other operators such as physicians specialized in Sport Medicine was stressed. Further, the holders of the new degree in Human Movement and Sport Sciences were considered fundamental contributors for the performance of physical activity and their presence was seen as a promising opportunity for the Departments of Prevention. Primary prevention based on recreational physical activities should become easily accessible for the population, avoiding obstacles such as certification steps or complex bureaucracy. The Sport Doctor is recognized as the principal referent for preliminary physical evaluation and clinical monitoring in secondary and tertiary prevention actions based on adapted physical activities. Developing research in the field is essential as well as implementing higher education on physical activity management in Schools of Public Health.

Blood Pressure Regulation by CCR Genes

New genetic evidence strongly supports a role for the immune system in the pathogenesis of essential hypertension (EH) through chemokines and their receptors (CCR) involvement. The aim of the present study was to evaluate the possible relation between CCR2 and CCR5 alleles and blood pressure (BP) levels in hypertensive subjects. In all, 118 essential hypertensive outpatients (male 90, female 28; stage I and II; age 27-54 years; not previously treated with antihypertensive drugs) were selected for the study. All of the subjects underwent office BP measurement. Subsequently, 24-h ambulatory BP monitoring (ABPM) was performed with a Spacelabs 90207 monitor during a regular working day. CCR264I and CCR5Delta32 polymorphisms were determined by polymerase chain reaction (PCR), following the standard molecular biology protocols. Allelic frequencies were the following: CCR5Delta32= 0.097, CCR264I=0.101. Logistic regression analysis showed an association between the CCR5Delta32 allele and the following: 24-h systolic BP (SBP >140 mmHg; p = 0.027), values over the 50th percentile of 24-h SBP (p = 0.032), and the values over the 50th percentile of nighttime SBP (p = 0.039). Office BP showed an association with the Delta32 allele in a range over the 75th percentile of SBP (p = 0.087) and the 75th percentile of DBP (p = 0.085). No significant association was observed for CCR264I and BP levels or between physiological nocturnal BP decline and genotype. The observed results not only support the role of the immune system in the development and maintenance of hypertension, but they also indicate an influence of CCR5Delta32 polymorphism on the establishment of BP levels.

[Health promotion through physical activity: territorial models and experiences]

Scientific evidences support the preventive role of physical activity in relation to different multifactorial pathologies. Health's promotion through the spreading of lifestyles that encourage movement, does not represent just an action in contrast with "sedentary life" risk-factor, but also a priority for "quality" of life, with relevant economical and social benefits. WHO indicates physical activity as one of the priorities for an effective prevention. Besides, the EU supports the realization and the diffusion of some prevention-programs. Main pilot experiences developed in Italy and other countries are summarized. Attention is focused on the role of the competences and structures involved in an integrated approach based on availability of medical support, social services and local structures, considering recent developments in health prevention and promotion. In Italy and Europe, new opportunities to implement health promotion through physical activity are offered by the development of higher education in movement and sport sciences.

Swimming pools and fungi: an environmental epidemiology survey in Italian indoor swimming facilities

A growing number of people attend swimming facilities for recreational activities, rehabilitative treatments, or sport. Filamentous fungi and yeast can be isolated from contaminated air, water and surfaces and may represent a biological risk for employees and users. Here we investigated the occurrence of mycotic species, in a sample of Italian swimming pools (n = 10). Detection and identification of isolated species were achieved by cultural and morphological methods. Results revealed moderate mycotic titres and a high biodiversity. Penicillium spp., Aspergillus spp., Cladosporium spp. and Alternaria sp., were constantly detected in air and surfaces sampled by the swimming area, while pathogenic yeast Candida albicans was never detected. Fusarium spp. was the most common taxon isolated from surfaces. For one facility, we typed the genotypic profiles and studied, by genetic typing, the spatial and temporal distribution of isolates. Phylogenetic relationships between species were analysed by alignment of small ribosomal subunit RNA sequences.

ACTN3 Genotyping by Real-Time PCR in the Italian Population and Athletes

PURPOSE

Development of two novel sets of primers and probes to detect R577X and Q523R polymorphisms of the alpha-actinin-3 (ACTN3) gene by real-time PCR. We report the allelic frequencies observed in Italian individuals from the general population and athletes. Athletic performance is influenced by training, environmental factors, and genetic predisposition. Actn3 belongs to a family of actin-binding proteins and is supposed to influence sport performance.

METHODS

Primer-probe set design and protocol optimization for real-time PCR genotyping of R577X and Q523R polymorphisms. The assay was verified using a traditional PCR-RFLP approach and applied on an Italian population sample (102 male subjects and 42 athletes).

RESULTS

Haplotype distribution confirmed the presence of linkage disequilibrium between the polymorphisms, both in the Italian general population and athletes (respectively: chi = 54.4, P < or = 0.001 and chi = 24.5, P < or = 0.001). Within the general population, a large percentage of homozygous subjects (21.6%) was deficient for Actn3. No significant differences were observed in athletes. The concordance between PCR-RFLP and real-time PCR results was 100and 93% for polymorphisms Q523R and R577X, respectively.

CONCLUSION

Real-time PCR represents an effective approach for typing ACTN3 alleles. Allelic frequencies in the Italian population are consistent with those seen in other studies on Caucasians.

[Aquaculture in Italy. An integrated model of product quality control]

Aquaculture is becoming increasingly diffuse even in Italy. The increased production introduces new problems such as product quality control and process safety. This article presents the results of a research project, funded by the Ministry of the Environment, whose aim was to evaluate and promote aquaculture product quality and safety in an environmentally responsible way. Four intensive land-based and offshore aquaculture sites were monitored to evaluate microbiological, biological and chemical (i.e. polychlorinated biphenyls and endocrine disruptors) quality of water, products and fish feed. In total 154 samples were analysed, of which 66 were water samples, 55 product samples and 33 feed samples. Salmonella and other enteric pathogens were absent in products and the aquatic environment, while other environmental pathogens of the Vibrio species were detected. Bacterial load and fecal indicators were found to be higher in off-shore products and in mussels from all aquaculture sites. PCBs were detected in all products in concentrations below 2 microg/g fresh product (Food and Drug Administration), but on average, higher concentrations were detected in off-shore products. No estrogen mimetic activity was detected in fish feed, in contrast it was detected in offshore products and water. Product quality was found to be strictly correlated with the quality of the environment. Genetically modified organisms were detected in fish feed but no integration of genetic material in products occurred.

A gzip-based algorithm to identify bacterial families by 16S rRNA

AIMS

Microbial family identification of 16S rDNA sequences by applying a strategy based on algorithms for data compression.

METHODS AND RESULTS

Perl scripts were developed to analyse similarities in microbial sequences, based on a gzip data compression technique. For each bacterial family (n=196) a 16S rRNA reference file was constructed to compare new queries looking at compression performance. An online user-friendly bioinformatics tool was built up to attribute a bacterial family to a 16S rRNA sequence. It was successfully applied to recognize different bacterial families, including Legionellaceae, Bacillaceae, Enterobacteriaceae, Acetobacteriaceae and Rhizobiaceae. The percentage of positive identifications is higher than 95% for fragments over 450 bp.

CONCLUSIONS

A new bioinformatics approach has been developed to assign a taxonomic classification to a 16SrDNA sequence. An online tool provides quick and easy sequence attribution. The general principle can be applied to other genes of taxonomic interest.

SIGNIFICANCE AND IMPACT OF THE STUDY

Availability of simple bioinformatics tools can support the development of molecular-based analysis and classification of bacteria, especially for environmental or uncultured strains.

Prospective 3-year surveillance for nosocomial and environmental Legionella pneumophila: implications for infection control

OBJECTIVES

To perform a 3-year, prospective surveillance program for legionnaires disease (LD) in a large university hospital in Rome, and to assess the usefulness of the hospital water monitoring program in predicting the risk of nosocomial LD.

METHODS

Samples from patients with new cases of nosocomial pneumonia were sent for legionella laboratory investigations. Meanwhile, water samples for bacteriological analysis were collected every 6 months from high- and medium-risk hospital wards (10 in total). Legionella pneumophila isolates collected were serotyped and analyzed by pulsed-field gel electrophoresis.

RESULTS

From June 2001 through May 2004, the pneumonia surveillance identified one case of nosocomial LD among 43 cases of nosocomial pneumonia (2.3%). Environmental investigations detected L. pneumophila in 12 (18.7%) of the 64 water samples, of which 50% belonged to serogroup 1. The L. pneumophila count and the percentage of positive locations never exceeded 10(2) colony-forming units/L and 20%, respectively, except when the LD nosocomial case occurred (positive water samples, 40%; L. pneumophila count, <10(2) colony-forming units/L). Genotyping showed 3 prevalent clones of L. pneumophila in the water distribution network, of which one persisted over the 3 years. One clone contained 3 different L. pneumophila serogroups (2, 4, and 6).

CONCLUSIONS

The low incidence of nosocomial cases of LD appears to be associated with a low percentage (<20%) of positive water samples per semester and with a low contamination level (<10(2) colony-forming units/L). An infection control system for nosocomial LD should, therefore, be based on both environmental and clinical surveillance, together with the appropriate maintenance of the hospital water distribution system.

Molecular epidemiology of Legionella pneumophila environmental isolates representing nine different serogroups determined by automated ribotyping and pulsed-field gel electrophoresis

The purposes of the study were (i) to describe the abundance and epidemiology of Legionellaceae in the man-made environment in a northern Italian area, (ii) to assess the concordance between pulsed-field gel electrophoresis (PFGE) and automated ribotyping (AR) techniques for genotyping L. pneumophila and (iii) to investigate the correlation between serogrouping and genotyping data. Water was sampled from reservoirs in 12 buildings across an area of 80-km radius. Despite the water temperature always being maintained above 55 degrees C, all of the buildings sampled were contaminated with Legionellaceae on at least one occasion and 63 L. pneumophila isolates representing nine different serogroups were collected. The two DNA methods revealed a high degree of genetic heterogeneity, even though identical L. pneumophila clones were recovered at different sites. The AR technique provided a fairly reliable approximation of PFGE results (73% concordance), however there was poor correlation between serogrouping and genotyping data as identical DNA fingerprints were shared by isolates of different serogroups.

Gene transfer and cauliflower mosaic virus promoter 35S activity in mammalian cells

The cauliflower mosaic virus 35S promoter (CaMV35s) is extensively used in genetically modified crops for human and animal consumption. Horizontal gene transfer is attracting particular attention, in light of experimental reports, showing the presence of dietary DNA into animal tissues. Health implications may derive from possible activities of the heterologous promoter in mammalian cells after integration in the host genome. To evaluate this hypothesis, in vivo and in vitro experiments were performed using GFP as reporter gene. Recombinant plasmid DNA was fed to Balb/c mice and searched in several tissues by PCR amplification. The activity of the plant virus promoter was assessed by RT-PCR and fluorescence microscopy after liposome-mediated transfection of murine gonadic cells. Obtained data did not highlight evidences of dietary DNA transfer in mice. No CaMV35s transcriptional activity was detected in this experimental model. These findings emphasize the need for further studies and standardized methods.

Legionella contamination in hot water of Italian hotels

A cross-sectional multicenter survey of Italian hotels was conducted to investigate Legionella spp. contamination of hot water. Chemical parameters (hardness, free chlorine concentration, and trace element concentrations), water systems, and building characteristics were evaluated to study risk factors for colonization. The hot water systems of Italian hotels were strongly colonized by Legionella; 75% of the buildings examined and 60% of the water samples were contaminated, mainly at levels of > or =10(3) CFU liter(-1), and Legionella pneumophila was the most frequently isolated species (87%). L. pneumophila serogroup 1 was isolated from 45.8% of the contaminated sites and from 32.5% of the hotels examined. When a multivariate logistic model was used, only hotel age was associated with contamination, but the risk factors differed depending on the contaminating species and serogroup. Soft water with higher chlorine levels and higher temperatures were associated with L. pneumophila serogroup 1 colonization, whereas the opposite was observed for serogroups 2 to 14. In conclusion, Italian hotels, particularly those located in old buildings, represent a major source of risk for Legionnaires' disease due to the high frequency of Legionella contamination, high germ concentration, and major L. pneumophila serogroup 1 colonization. The possible role of chlorine in favoring the survival of Legionella species is discussed.

Lack of association of CCR gene polymorphisms and left ventricular hypertrophy in essential hypertension

Left ventricular hypertrophy (LVH) is a major determinant of heart damage. Scientific evidence suggests the influence of genetic factors, but these have yet to be completely clarified. This study investigates a possible relationship between LVH and two chemokine receptor (CCR) gene polymorphisms: CCR5delta32 and CCR264I. Essential hypertensive out-patients (n=118, grade I-II, age 27-54) were recruited from the Catholic University Hypertension Centre. For each subject, clinical data on office blood pressure and M-mode/2D echocardiography were collected. Statistical analysis did not show a significant association between the CCR polymorphisms and LVH in the study population.

Sulfotransferase 1A1 polymorphism and gastric cancer risk: a pilot case-control study

Sulfotransferases (SULT) catalyse both the bioactivation and detoxification of a wide range of promutagens and carcinogens. The SULT1A1 gene possesses a G-->A polymorphism that results in a Arg to His substitution at codon 213, and the His allele has been shown to have a low activity and thermal stability. To test the hypothesis that individuals carrying the variant allele may be at high risk of gastric cancer, we identified the SULT1A1 Arg213His genotype by a PCR-based RFLP in a preliminary study of 76 gastric adenocarcinoma patients that underwent curative gastrectomy and 260 age and sex-matched controls from a medical centre in Rome. A comprehensive epidemiological interview was conducted on all participants to collect lifestyle data. The prognostic significance of the SULT1A1 Arg213His polymorphism with respect to staging, differentiation and histological type of gastric cancer was also evaluated. The frequencies of His/His in cases and controls were 11.9% (9/76) and 5% (13/260), respectively (P=0.025). After adjusting for substance use, age, gender and physical activity, individuals with His/His showed a 3.32 fold increased risk of developing gastric cancer compared to those with Arg/Arg (95% CI=1.17-9.45). This positive association was more pronounced amongst males, alcohol drinkers, current smokers and consumers of grilled/barbecued meat and, unexpectedly, amongst individuals with a high intake of fruit. A statistically significant association was also found between the diffuse type of gastric cancer and the heterozygous SULT1A1 genotype. Our preliminary findings suggest for the first time that the SULT1A1 His213 allele may be important in the development of gastric cancer, with other factors modulating such effect.

Gene expression evidence for remodeling of lateral hypothalamic circuitry in cocaine addiction

By using high-density oligonucleotide arrays, we profiled gene expression in reward-related brain regions of rats that developed escalated cocaine intake after extended access to cocaine (6 h per day). Rats allowed restricted daily access to cocaine (only 1 h) that displayed a stable level of cocaine intake and cocaine naive rats were used for controls. Four analysis methods were compared: Affymetrix microarray suite 4 and microarray suite 5, which use perfect-match-minus-mismatch models, and dchip and rma, which use perfect-match-only models to generate expression values. Results were validated by RT-PCR in individual animals from an independent replication of the experiment. A small number of genes was associated with escalated cocaine intake (ESC genes). Unexpectedly, of the brain regions examined [prefrontal cortex, nucleus accumbens, septum, lateral hypothalamus (LH), amygdala, and ventral tegmental area], the LH was the most transcriptionally responsive in escalation of cocaine intake. Most of the ESC genes identified are also expressed during synaptogenesis and synaptic plasticity and include genes that code for several presynaptic and postsynaptic proteins involved in neurotransmission. These results suggest that LH intrinsic circuitry undergoes a structural reorganization during escalation of cocaine use. This remodeling of LH circuitry could contribute to the chronic deficit in reward function that has been hypothesized to drive the transition to drug addiction. Results also support the value of using multiple analysis strategies to identify the most robust changes in gene expression and to compensate for the biases that affect each strategy.

[A preliminary investigation on the occurrence of protozoa in swimming pools in Italy]

In Italy controls on the hygienic quality of swimming pools are fixed by the Accordo tra il Ministero della Salute, le regioni e le province autonome di Trento e di Bolzano, come into force in 2003. In the present study swimming pools were investigated from the microbiological point of view on the basis of the new legislation. Contemporaneously, for the first time in Italy, analytical controls on the occurrence of the protozoa Cryptosporidium and Giardia were performed with both techniques of immunofluorescence and polymerase chain reaction. Results evidenced a good water quality when the bacterial parameters stated by law were considered. However in some swimming pools, the protozoa were also recovered. Factors affecting the use of molecular techniques on the analysis of environmental samples are also put into evidence.

Legionella infection risk from domestic hot water

We investigated Legionella and Pseudomonas contamination of hot water in a cross-sectional multicentric survey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age, and mineral content. Pseudomonas presence was influenced by water source, hardness, free chlorine, and temperature. Legionella contamination was associated with a centralized heater, distance from the heater point >10 m, and a water plant >10 years old. Furthermore, zinc levels of <20 μg/L and copper levels of >50 μg/L appeared to be protective against Legionella colonization. Legionella species and serogroups were differently distributed according to heater type, water temperature, and free chlorine, suggesting that Legionella strains may have a different sensibility and resistance to environmental factors and different ecologic niches.

Public health issues related with the consumption of food obtained from genetically modified organisms

Genetically Modified Organisms (GMOs) are a fact of modern agriculture and a major field of discussion in biotechnology. As science incessantly achieves innovative and unexpected breakthroughs, new medical, political, ethical and religious debates arise over the production and consumption of transgenic organisms. Despite no described medical condition being directly associated with a diet including approved GM crops in large exposed populations such as 300,000,000 Americans and a billion Chinese, public opinion seems to look at this new technology with either growing concern or even disapproval. It is generally recognized that a high level of vigilance is necessary and highly desirable, but it should also be considered that GMOs are a promising new challenge for the III Millennium societies, with remarkable impact on many disciplines and fields related to biotechnology. To acquire a basic knowledge on GMO production, GM-food consumption, GMO interaction with humans and environment is of primary importance for risk assessment. It requires availability of clear data and results from rigorous experiments. This review will focus on public health risks related with a GMO-containing diet. The objective is to summarize state of the art research, provide fundamental technical information, point out problems and perspectives, and make available essential tools for further research. Are GMO based industries and GMO-derived foods safe to human health? Can we consider both social, ethical and public health issues by means of a constant and effective monitoring of the food chain and by a clear, informative labeling of the products? Which are the so far characterized or alleged hazards of GMOs? And, most importantly, are these hazards actual, potential or merely contrived? Several questions remain open; answers and solutions belong to science, to politics and to the personal opinion of each social subject.

[Genetic screenings: state of the art and perspectives for public health]

Management of genetic data needs the fulfillment of technical requirements, involving ethics, law, and social issues. Introduction of genetic information in preventive medicine implies complex consequences and specialized expertise. Genetic screenings represent a promising tool, but further advances are needed to provide their effective and appropriate use in the respect of the privacy. Application areas, tests validation procedures and availability of effective laboratory and qualified service networks are considered. The Authors present main laws and bioethics guidelines in the field.

Biological effects of EMF exposure on Ets genes

Ets genes are transcription factors expressed in different tissues. Biochemical pathways interfering with the intracellular calcium ion concentration are known to influence members of this gene family. Considering experimental observations and previous reports, we proposed a hypothetical model of interaction between EMF and Ets, based on possible interference in pathways involving calcium as a second messenger. This approach comprehend different hypothesis and may contribute to clarify EMF biological effects, providing an experimental model and a procedure based on gene expression analysis. Additional knowledge on biological mechanisms is required to support these promising results. Further experiments are in progress to assess the role of EMF in modulating gene expression and its biological meaning. Identification of early endpoints is needed for mechanism understanding and development of sensitive biomarkers for molecular epidemiology studies.

[Environmental diffusion of Legionella spp and legionellosis frequency among patients with pneumonia: preliminary results of a multicentric Italian survey]

A multicentric Italian investigation on legionnaires' disease is in course to clarify host factors as well as pathogen associated characteristics involved in the infection/disease. The main goal of the research plan is to account for some critical aspects concerning identification and prevention of legionellosis. To improve knowledge on factors associated with Legionella spp colonisation in hot waters, to detect cases and to characterize risk factors in subjects which develop pneumonia are specific objectives of the research programme. Preliminary results show that hot waters of houses and hotels are frequently contaminated (22.6% and 54.6%, respectively), mainly by L. pneumophila. Microbial concentrations were low in domestic waters (<1.000 ufc/l), but higher in samples from the hotels (geom. mean 1.85 x 10(3) ufc/l). Warming system, age of the plant, type of building were risk factors significantly associated with Legionella spp positivity. The active surveillance on patients affected by pneumonia with search for Legionella urinary antigen allowed the identification of 34 cases, 3 of which of nosocomial origin, corresponding to 4.2% of the screened pneumonia. After informed consent, 26 subjects were recruited for a case-control-study to clarify risk factors for the disease.

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.

Relationship between mineral content of domestic hot water and microbial contamination

The relationship between Legionella and Pseudomonas spp contamination and mineral content of domestic hot waters was investigated in a cross-sectional Italian survey. Pseudomonas spp contamination was associated with elevated Ca, but lower Fe and free chlorine content in the water. Waters with Cu concentrations > 50 microg/L prevented Legionella spp colonisation (OR = 0.14, 95% CI = 0.02-1.13), whereas the risk of legionellae occurrence increased in waters with Mn levels > 3 microg/L (OR = 2.37, 95% CI = 1.06-5.30). Furthermore, Mn was positively associated with the risk of colonisation by eterotrophic bacteria growing at either 22 and 36 degrees C. Legionella species and serogroups were differently distributed according to Cu and Mn concentrations, suggesting that Legionella strains may have a different sensibility/resistance to trace elements. A specific action of Cu as decontamination factor is suggested and the consideration of Mn as a risk indicator for bacterial colonisation and biofilm presence is proposed.

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.

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 .

In vivo modulation of ETS genes induced by electromagnetic fields

We have previously shown that electromagnetic field (EMF) exposure induces ETS1 oncogene overexpression in different cell lines. In order to investigate in vivo EMF effects, BALB/c mice were exposed at different times to 50 MHz radiation, modulated (80%) at 16 Hz. The exposed and control animals were sacrificed and the spleen excised for rt-pcr and western blot analysis. We observed an increase in ETS1 mRNA and protein expression, but a decrease in ETS2 protein levels. Preliminary results from this experimental model show in vivo evidence of the effect of EMF on ETS oncogene expression.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.