Antifungal activity of extracts and purified saponins from the rhizomes of Chamaecostus cuspidatus against Candida and Trichophyton species.

AIM: To evaluate the antifungal activity of extracts of Chamaecostus cuspidatus against Candida and Trichophyton species. METHODS AND RESULTS: Crude ethanol extracts of leaves, stems and rhizomes were prepared and evaluated for antimicrobial activity. Only the rhizomes extract (RE) showed antifungal activity but had no inhibitory effect against bacteria (Staphylococcus aureus and Escherichia coli). The RE was then submitted to liquid-liquid partition with hexane (Hex), dichloromethane, chloroform, ethyl acetate and water. The Hex fraction (Hex Fr) from the RE was found to have the best antifungal effect. Three known saponins were isolated from the Hex Fr, of which two (dioscin and aferoside A) showed good antifungal activity. In addition, Hex Fr and the two bioactive compounds had no antibacterial effect, but exhibited fungicidal activity, caused significant changes in the morphology of the fungal cells and showed anti-Candida albicans biofilm activity. Finally, the bioactive plant products presented greater selectivity for fungal cells over normal human cells. CONCLUSIONS: The rhizomes of C. cuspidatus have bioactive saponins that function as effective antifungals against Candida and Trichophyton species, and have antibiofilm activity against C. albicans. SIGNIFICANCE AND IMPACT OF THE STUDY: Chamaecostus cuspidatus REs may have potential clinical application towards the management of superficial mycoses caused by Candida and Trichophyton species.

Are 6-8 year old Italian children moving away from the Mediterranean diet?

BACKGROUND: The Mediterranean diet (MD) is considered one of the healthiest dietary models, as it decreases the risk of chronic diseases and may modulate the organism's early response to environmental pollution. In recent decades, Mediterranean countries have been replacing their traditional diet with other less healthy eating habits, especially among children and teenagers. OBJECTIVE: The aim of this study was to evaluate the MD and the level of adherence to it in 6-8 year old Italian children, in relation to residence, lifestyle, and social and family contexts. METHODS: A questionnaire was administered to the children's parents in two seasons in 5 Italian towns. The diet section contained 116 questions investigating the frequency of consumption of different types of food. The Italian Mediterranean Index (IMI) was calculated according to the intake of 6 typical Mediterranean and 4 non-Mediterranean foods. On the basis of IMI score, MD adherence was classified as low (≤ 3 IMI score), medium (4-5) and high (≥ 6). Total energy load and diet composition in micro- and macronutrients were calculated from consumption frequency. RESULTS: Diet analysis was computed on 1164 subjects with two complete questionnaires. Body mass index, calculated for each subject, showed that 28.9% of the children were overweight, the figure varying slightly with area of residence. Our findings showed that 59.0% of the children had a low score for MD adherence. CONCLUSIONS: The results of this study showed that most Italian children did not follow the MD and socio-economic characteristics appeared not to be associated with type of diet.

Feasibility and reliability of a questionnaire for evaluation of the exposure to indoor and outdoor air pollutants, diet and physical activity in 6-8-year-old children.

INTRODUCTION: The MAPEC-Life project aims to study the biological effects of early exposure to air pollutants on the oral mucosa cells of school-age children in five Italian cities. A questionnaire was created to evaluate the association between outdoor and indoor airborne pollutants, lifestyle, diet and biomarker effects. The feasibility and reliability of the questionnaire were evaluated. METHODS: A questionnaire was drawn up to be filled in by the parents of 6-8-year-old children. It consisted of 148 questions on the children's health, physical activity, environmental exposures and the frequency of food consumption at the main meals. First we conducted a questionnaire feasibility study involving 53 volunteer parents. We then performed a reliability study by administering the questionnaire to a further 156 parents and again one month later (test/retest method). The correlations between answers at the first and second administration of the questionnaire were evaluated using the Kappa statistic and Spearman's coefficient. RESULTS: After verifying the feasibility of the questionnaire, we conducted a reliability analysis on 132 completed questionnaires. The percentage of agreement between the first and the second responses given was over 70%, all K values being greater than 0.6. The analysis of calories and macronutrients also showed good agreement. CONCLUSIONS: The questionnaire drawn up for the study proved to be sufficiently reliable for gathering information about the factors of interest in our study of the relationship between air pollution and early biological effects in children.

[Chronic exposure to organochlorine compounds and health effects in adults: cancer, non-Hodgkin lymphoma. Review of literature]. / Esposizione cronica a organoclorurati ed effetti sulla salute nell'adulto. Revisione sistematica della letteratura. Seconda parte: Tumori.

International Agency for Research on Cancer (IARC) has classified 2,3,7,8 tetrachlorodibenzo-p-dioxin (TCDD) as human multisite carcinogen though not associated to specific tumours. Other dioxins and furans are not classified as carcinogenic due to lack of scientific evidence, and polychlorobiphenyls (PCBs) are classified as probable carcinogens. The aim of this research is to focus the association between chronic exposure to organochlorine compounds and cancer in adults. We included cohort studies among occupationally exposed workers or in populations exposed to high levels of these chemicals in the environment, and cohort and case-control studies using measure of internal dose of exposure. Overall, cohort studies among heavy exposed people do not show an increased risk of developing cancer and do not show consistent results as regards in specific sites neoplasms. Among epidemiologic analytical studies with individual measures of exposure, most, though not all, found an association between Non-Hodgkin lymphoma and PCB serum level concentrations. Weak evidence, if any, was available as regards the association between organochlorine compounds and other cancers.

[Chronic exposure to organochlorine compounds and health effects in adults: diabetes and thyroid diseases]. / Esposizione cronica a organoclorurati ed effetti sulla salute nell'adulto. Revisione sistematica della letteratura. prima parte: Malattie della tiroide e diabete.

Organochlorine compounds are widely distributed in the world and may persist in both the environment and living organisms. They are fat-soluble compounds and people are usually exposed to them through food, inhalation or dermal contact. They are classified as POPs (persistent organic pollutants), as they persist in the environment for a long time and move up through the food chain. DTT and other synthetic pesticides, polychlorinated dibenzodioxins (PCDD), polychlorinated dibenzofurans (PCDF) and polychlorobyfenils (PCB) are among the most diffused POPs worldwide. Experimental studies show that some of these chemicals have endocrine disruption activity and particularly that they can alter the thyroid function. Furthermore, recent studies in humans show that exposure to some organochlorine compounds may increase the risk of type II diabetes mellitus. This review provides a synthesis of the results of epidemiologic studies regarding the association between organochlorines exposure and thyroid diseases and diabetes. We included published studies with measures of internal dose of exposure (usually, serum concentration) in adults. We retrieved 22 studies for thyroid diseases and 22 on diabetes. Overall, we found contrasting results among the studies, with about half of them showing a statistically significant association between serum concentration of organochlorines and the diseases investigated.

Antifungal activities of compounds isolated from Piper abutiloides Kunth.

Piperaceae is a family of tropical plants known to have antifungal, antibacterial, tumour-inhibitory, antiviral, antioxidant, molluscicidal and leishmanicidal activities. In this work, extracts and fractions from aerial parts of Piper abutiloides (Piperaceae), a traditional medicinal plant, were evaluated against the fungal species Candida albicans, C. parapsilosis, C. krusei, C. glabrata, C. tropicalis, Cryptococcus neoformans and Sporothrix schenckii. The results have shown that the antifungal activity of this plant can be concentrated in the hexanic fraction after partitioning its hydroalcoholic extract between hexane and 90% aqueous methanol. The chromatographic fractionation of the bioactive part was monitored with a bioautographic assay using C. glabrata, and allowed the isolation of three antifungal compounds: pseudodillapiol, eupomatenoid-6 and conocarpan. These compounds presented different potencies against the fungi tested, with the strongest effect being observed for eupomatenoid-6 against C. glabrata, which presented a minimal inhibitory concentration value of 0.3 microg spot(-1). Conocarpan showed antifungal activity without apparent cytotoxic effect on normal human lymphocytes, as assessed by the proliferation assay with human peripheral blood mononuclear cells stimulated with phytohaemaglutinin. This work reveals for the first time the occurrence of these compounds in P. abutiloides and justifies further studies to clarify their mechanisms of action.

Evaluation of chlorite and chlorate genotoxicity using plant bioassays and in vitro DNA damage tests.

In the last few years chlorine dioxide has been increasingly used for disinfecting drinking water in many countries. Although it does not react with humic substances, chlorine dioxide added to water is reduced primarily to chlorite and chlorate ions, compounds that are under investigation for their potential adverse effects on human health. The aim of this research was to study the genotoxicity of chlorite and chlorate and their mixtures. The end-points included two plant tests (chromosomal aberration test in Allium cepa and micronucleus assay in Tradescantia, carried out at different times of exposure) and two genotoxicity tests in human HepG2 cells (comet assay and cytokinesis-blocked micronucleus test). Preliminary toxicity tests were carried out for both plant and HepG2 assays. The results showed that chlorite and chlorate are able to induce chromosomal damage to plant systems, particularly chromosomal aberrations in A. cepa root tip cells, even at concentrations lower than the limit established by Italian normative law and WHO guidelines. In HepG2 cells increased DNA damage was only observed for chlorate at the lowest concentration. No increase in micronuclei frequency was detected in any of the samples tested in human HepG2 cells.

Characterization of the cDNA of a broadly reactive neutralizing human anti-gp120 monoclonal antibody.

The F105 mAb, identified in an HIV-1-infected individual, binds to a discontinuous epitope on the HIV-1 gp120 envelope glycoprotein, blocks the binding of gp120 to the CD4 viral receptor, and neutralizes a broad range of HIV-1 isolates. This study reports the primary nucleotide and deduced amino acid sequences of the rearranged heavy and light chains of the mAb F105. This IgG1k mAb uses a VH gene member of the VH4 gene family (V71-4) and is productively rearranged with a D-D fusion product of the dlr4 and da4 germline DH genes and the JH5 gene. This rearranged heavy chain gene expresses the VH4-HV2a idiotope, which is seen in human monoclonal IgM cold agglutinins. The F105 Vk appears to be derived from the Humvk325 germline gene and is rearranged with a Jk2 gene. For both chains, the mutational pattern in the rearranged VH and VL genes is indicative of an antigen-driven process. These studies show that production of a broadly neutralizing anti-HIV-1 antibody that recognizes determinants within the CD4 recognition site of the envelope glycoprotein is achieved by rearrangement of the V71-4 and Humvk325 germline variable region genes along with selected individual point mutations in the rearranged genes.

Genotoxicity of the disinfection by-products resulting from peracetic acid- or hypochlorite-disinfected sewage wastewater.

Wastewater disinfection is routinely carried out to prevent the spread of human pathogens present in wastewater effluents. To this aim, chemical and physical treatments are applied to the effluents before their emission in water bodies. In this study, the influence of two widely used disinfectants, peracetic acid (PAA) and sodium hypochlorite (NaClO), on the formation of mutagenic by-products was investigated. Wastewater samples were collected before and after disinfection, in winter and in summer, at a pilot plant installed in a municipal wastewater-treatment plant. Samples were adsorbed using silica C18 cartridges and the concentrates were tested for mutagenicity in the Salmonella typhimurium reversion test with strains TA98 and TA100. Non-concentrated water samples were tested with two plant genotoxicity assays (the Allium cepa root anaphase aberration test and the Tradescantia/micronucleus test). Mutagenicity assays in bacteria and in Tradescantia showed borderline mutagenicity in some of the wastewater samples, independent of the disinfection procedure applied. Negative results were obtained in the A. cepa anaphase aberration test. These results indicate that, in the conditions applied, wastewater disinfection with PAA and NaClO does not lead to the formation of significant amounts of genotoxic by-products.

Ex-vivo evaluation of the three-column concept in canine thoracolumbar fractures / [Avaliação em ex-vivo do conceito dos três compartimentos em fraturas toracolombares da coluna]

Traumatic events such as a motor vehicle accident or falling from heights are very common in veterinary medicine and often lead to vertebral fracture-luxation with concomitant spinal cord injuries, mostly in the thoracolumbar spine. The purpose of this cadaveric biomechanical study was to determine the feasibility of the three-column concept in canine thoracolumbar segments with induced fractures. Eighteen Functional Spinal Units (FSU) of the thoracolumbar segments (T12-L2) were collected from 18 medium-sized adult dog cadavers and were subjected to flexion-extension and lateral bending tests so that range of motion (ROM) was recorded with a goniometer. Fractures were induced by compressive loads applied by a universal testing machine (EMIC®). After this, specimens were screened using computed tomography (CT) and the fractures were graded as affecting one, two or three columns, and divided into groups A, B, and C, respectively. Post-fracture range of motion (ROM) was compared with the previous results. Groups B and C (with fractures in two or three columns) had instability in the two axes evaluated (P<0.05). The outcomes of this study support the applicability of the three-column theory to thoracolumbar spines of dogs, as the FSUs that suffered fractures in two or more columns showed axial instability.(AU)

Eventos traumáticos, como acidentes automobilísticos ou quedas, são muito comuns na medicina veterinária e, frequentemente, levam a fraturas ou luxações vertebrais, associadas a lesões medulares concomitantes, mais frequentemente na coluna toracolombar. O propósito deste estudo biomecânico em cadáveres foi determinar a viabilidade da teoria dos três compartimentos em fraturas induzidas em segmentos toracolombares de cães. Dezoito unidades espinhais funcionais (UEF) de segmentos toracolombares (T12-L2) foram coletadas de 18 cadáveres de cães adultos de médio porte e submetidas a testes de flexão-extensão e curvamento lateral, de modo que a amplitude de movimento (ADM) foi registrada com um goniômetro. Fraturas foram induzidas por meio de cargas compressivas aplicadas por uma máquina universal de ensaios (EMIC®). As amostras foram submetidas à tomografia computadorizada (TC), e as fraturas foram classificadas como afetando um, dois ou três compartimentos e divididas nos grupos A, B e C, respectivamente. A ADM pós-fratura foi comparada com os resultados prévios. Os grupos B e C (com fraturas em dois ou três compartimentos) apresentaram instabilidade nos dois eixos avaliados (P<0,05). Os resultados deste estudo corroboram a aplicabilidade da teoria dos três compartimentos para segmentos de coluna toracolombar em cães, uma vez que as UEF que sofreram as fraturas em dois ou mais compartimentos apresentaram instabilidade axial.(AU)

Monitoring of volatile and non-volatile urban air genotoxins using bacteria, human cells and plants.

Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 µg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p < 0.01). Aqueous extracts collected in January and February induced genotoxic effects in Tradescantia exposed in the laboratory (p < 0.01). Ames test showed that organic extracts of winter urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants.

A new cyclohexadecane derivative from Trixis vauthieri DC (Asteraceae).

The dichloromethane-methanol extract from the fresh leaves of Trixis vauthieri DC (Asteraceae) afforded trixol, a new cyclohexadecane derivative. The structural elucidation of this new compound, with a novel skeleton, was based on NMR studies of the natural product nd its derivatives.

Genotoxicity of surface water treated with different disinfectants using in situ plant tests.

Disinfection of surface drinking water, in particular water chlorination, results in many by-products with potential genotoxic and/or carcinogenic activity. In the present study, we evaluated the genotoxicity of surface water after treatment with different disinfectants by means of in situ plant genotoxicity assays (micronucleus and chromosomal aberration tests) which can detect both clastogenic and aneugenic effects. The study was carried out at a pilot plant using lake water after sedimentation and filtration. This water supplied four stainless steel basins: three basins were disinfected with sodium hypochlorite, chlorine dioxide, and peracetic acid and the fourth basin containing untreated lake water was used as a control. Plants were exposed in situ in the basins. The study was carried out using water collected in different seasons over a period of about 1 year in order to assess the treatments in different physical and chemical lake water conditions. The micronucleus test in root cells of Vicia faba (Vicia faba/MCN test) revealed genotoxicity in many samples of disinfected water. The micronucleus test in Tradescantia pollen cells and the chromosome aberration test in root cells of Allium cepa showed genotoxic effects only in some disinfected samples, but also revealed genotoxicity in raw water. The results of the study indicated that the Vicia faba/MCN test was the most sensitive plant assay for disinfected water and that peracetic acid disinfection produced similar or lower genotoxicity than sodium hypochlorite or chlorine dioxide treatment.

A cytotoxic diterpene from Alomia myriadenia.

An extract of the aerial parts from Alomia myriadenia Schultz-Bip. ex Baker (Asteraceae) showed significant cytotoxicity against a panel of human cancer cell lines in a screening of extracts from Brazilian Atlantic Forest plant species. Employing a bioassay-linked HPLC-electrospray/MS method, followed by semi-preparative HPLC, the active component was isolated and characterized as a mixture of epimers of the labdane diterpene 12S,16-dihydroxy-ent-labda-7,13-dien-15,16-olide.

An improved HPLC method for the quantitation of 6-mercaptopurine and its metabolites in red blood cells.

A procedure is described for the rapid determination of the intra-erythrocyte concentration of 6-mercaptopurine (6-MP) and its metabolites, 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP). Erythrocytes (8 x 10(8) cells) in 350 microl Hanks solution containing 7.5 mg dithiothreitol were treated with 50 microl 70% perchloric acid. The precipitate was removed by centrifugation (13,000 g) and the supernatant hydrolyzed at 100 degrees C for 45 min. After cooling, 100 microl was analyzed directly by HPLC using a Radialpack Resolve C18 column eluted with methanol-water (7.5:92.5, v/v) containing 100 mM triethylamine. 6-TG, 6-MP and the hydrolysis product of 6-MMP, 4-amino-5-(methylthio)carbonyl imidazole, were monitored at 342, 322 and 303 nm using a Shimadzu SPD-M10A diode array UV detector. The analytes eluted at 5.3, 6.0 and 10.2 min, respectively. The calibration curves were linear (r(2) > 0.998), and the analytical recoveries were 73.2% for 6-TG, 119.1% for 6-MP and 97.4% for 6-MMP. The intra- and inter-assay variations were highest for 6-MP (9.6 and 14.3%, respectively). The lowest detectable concentrations were 3, 3 and 25 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The quantification limits (coefficients of variation <15%) were 8, 10 and 70 pmol/8 x 10(8) erythrocytes for 6-TG, 6-MP and 6-MMP, respectively. The method was applied to the analysis of 183 samples from 36 children under chemotherapy for acute lymphoblastic leukemia. The concentrations of the metabolites in the red cells of the patients ranged from 0 to 1934 pmol/8 x 10(8) erythrocytes for 6-TGN, and from 0 to 105.8 and 0 to 45.9 nmol/8 x 10(8) erythrocytes for 6-MP and 6-MMP, respectively. The procedure gave results that were in agreement with those obtained with other methods designed to detect cases of non-compliance with treatment, including patient interviews and medical evaluation, among others, demonstrating its applicability to monitoring the treatment of leukemic children.

Evaluation of the migration of mutagens/carcinogens from PET bottles into mineral water by Tradescantia/micronuclei test, Comet assay on leukocytes and GC/MS.

This study monitored the release of mutagenic/carcinogenic compounds into mineral water (natural and carbonated) from polyethylene terephthalate (PET) bottles, using a plant mutagenicity test which reveals micronuclei formation in Tradescantia pollen cells (Trad/MCN test), a DNA damage assay (Comet assay) on human leukocytes and gas chromatography/mass spectrometry (GC/MS) for the characterisation of migrants. The water samples were collected at a bottling plant and stored in PET bottles for a period ranging from 1 to 12 months. Every month some samples were randomly collected and lyophilised, the residual powders were extracted with organic solvents and then analysed by GC/MS and tested for DNA damage in human leukocytes, or reconstituted with distilled water to obtain concentrates for the exposure of Tradescantia inflorescences. Micronuclei increase in pollen was found only in natural mineral water stored for 2 months. DNA-damaging activity was found in many of the natural and carbonated water samples. Spring water was negative in the plant micronuclei test and the Comet assay, whereas distributed spring water showed DNA-damaging effects, suggesting a possible introduction of genotoxins through the distribution pipelines. GC/MS analysis showed the presence in mineral water of di(2-ethylhexyl)phthalate, a nongenotoxic hepatocarcinogenic plasticizer, after 9 months of storage in PET bottles.

[Preliminary trials of Guaiacum officinale L. as a molluscicide]. / Ensaios preliminares do Guaiacum officinale L. como moluscicida.

Aqueous suspensions of fruit's pericarp, leaves, root's bark and seeds of Guaiacum officinale were tested at different concentrations as molluscicide, cercaricide and piscicide. In the laboratory the suspension of fruit's pericarp produced 100% mortality for egg masses of B. glabrata at 100 ppm, for adult snails of Biomphalaria glabrata, B. straminea and B. tenagophila at 20 ppm, for Lebistes reticulatus (fishes) at 5 ppm and Schistosoma mansoni's cercariae at 1 ppm. The ethanolic extract of fruit's pericarp was not active against adult snails of B. glabrata. The lethal dose for adult snails(DL90) of the aqueous suspension of fruit's pericarp after 24 hours exposure, were: 15 ppm for B. glabrata; 14 ppm for B. straminea and 18 ppm for B. tenagophila. The DL90 of aqueous suspensions of root's bark, seeds and leaves were 57 ppm, 33 ppm and 15 ppm, respectively. In the field, B. glabrata adult snail mortality was 68% at 20 ppm and 100% at 40 ppm, when using suspension of fruit's pericarp.

[Decontamination of dental unit waterlines using disinfectants and filters]. / Decontaminazione del sistema idrico del riunito mediante disinfezione e filtrazione.

Bacterial contamination of the dental unit water system can become a health problem for patients, particularly if they are immunodepressed. The present study has had the purpose of evaluating the effectiveness of methods of chemical decontamination using different disinfectants (peracetic acid, hydrogen peroxide, silver salts, chloramine T, glutaraldehyde T4) and methods of physical decontamination using synthetic membranes for the filtration of water. A preliminary removal procedure of the biofilm present in the waterline has been followed in a dental unit prepared on purpose for the research; subsequently different 2-week long maintenance procedures were applied using disinfectants injected by a pump and finally the bacterial contamination of the water flowing from the waterline was evaluated. The physical decontamination was performed using 0.22 mm membrane filters, which have been installed also in another dental unit, and the filtered water was analyzed to detect bacterial contamination. The preliminary procedure of biofilm removal succeeded obtaining germ-free water. Among the disinfectants used for the maintenance of the water quality only glutaraldehyde T4 was able to reduce the bacterial contamination under the limit suggested by the ADA. The membrane filter system was not able to purify the water, but when a disinfectant (peracetic acid) was used in the last part of the waterline good results were obtained. At present no decontamination system of dental waterline is available, and glutaraldehyde T4 seems to be the best disinfectant only if integrated with periodic biofilm removal for the maintenance of the water quality.

[Environmental monitoring of infective risks in Italian dental offices]. / Monitoraggio ambientale dei rischi infettivi legati all'assistenza odontoiatrica.

BACKGROUND: Bacterial contamination in dental offices plays a primary role in the evaluation of infective risks for patients and dental personnel. The aim of the research was to study bacterial contamination in eight Italian dental offices by investigating the water of dental units, the air and certain surfaces (push-button panel and instrument cabinet) in order to evaluate potential risks in dental practices. METHODS: The water underwent a microbiological test as specified by Italian law (DPR 236/88). The water was sampled from the hoses and air/water syringes of twenty dental units. The microbiological analysis of the air was performed using sedimentation plates to evaluate microbial fall-out. The microbiological analysis of the surfaces was performed using membrane filters to evaluate microbial accumulation. RESULTS: The research showed bacteriological contamination of the dental unit water in all the dental offices. During the working activity total bacteriological counts in the air fall-out were fairly high and the surfaces examined showed some widespread bacterial contamination in dental practices. The results of this study show the importance of routine monitoring of microbial contamination of dental offices and, in case of contamination, the need to apply disinfection treatments for the waterlines and preventive measures for the aerosol reduction. CONCLUSIONS: Our research was used to work out a program for the prevention of environmental contamination in dental offices.

[Genotoxicity of surface water treated with different disinfectants using in situ plant tests]. / Valutazione della genotossicità di acque superficiali trattate con diversi disinfettanti mediante test su vegetali.

Disinfection of surface drinking water, in particular water chlorination, produces many by-products with genotoxic and/or carcinogenic activity. The aim of this research was to evaluate the genotoxicity of surface water after treatment with different disinfectants by means of in situ plant genotoxicity assays. The study was carried out in a pilot plant using lake water after sedimentation and filtration, which supplied four stainless steel basins: three basins were disinfected with sodium hypochlorite, chlorine dioxide and peracetic acid, respectively, and the fourth basin contained untreated lake water and was used as a control. The study was carried out using water collected in different seasons over a period of about one year in order to assess the treatments under different physical and chemical lake water conditions. Plant genotoxicity tests were performed by exposing plant bioindicators directly to raw and disinfected water. The Tradescantia micronucleus test in pollen cells of the flowers of an hybrid of Tradescantia and the Allium cepa test, a chromosome aberration test in root cells of Allium cepa, showed genotoxic effects only in some disinfected samples and revealed genotoxicity also in raw water in one experiment. The Vicia faba test, a micronucleus test in root cells of Vicia faba, revealed genotoxicity in many samples of disinfected water. The results of the study indicated that the Vicia faba/MCN test was the most sensitive plant assay for disinfected water, and that peracetic acid disinfection produced lower genotoxicity than sodium hypochlorite or chlorine dioxide treatment.