Gene-specific promoter methylation is associated with micronuclei frequency in urothelial cells from individuals exposed to organic solvents and paints.

Sufficient epidemiologic evidence has established an etiologic link between bladder cancer risk and occupational exposure as a painter to organic solvents. Currently, it remains to be established whether gene-specific promoter methylation contributes to bladder cancer development, including by enhancing chromosome breakage or loss. We investigated the effect of chronic exposure to organic solvents and paints on DNA methylation profiles in the promoter regions of four genes (GSTP1, p16(INK4a), APC and CDH1) and micronucleus (MN) frequency in exfoliated urothelial cells from voided urine from Colombian male non-smoking car painters and age-matched unexposed individuals. The exposed group had a higher percentage of individuals with >2 MNs/2000 cells compared with the unexposed group (P=0.04). Gene-specific analysis showed a significantly higher percentage of individuals with methylated GSTP1, p16(INK4a) and APC in the exposed group. Poisson regression analysis indicated that exposed individuals with methylated GSTP1 and p16(INK4a) promoters were more than twofold more likely to have an increase in MN frequency as compared with the reference. Finally, among exposed individuals with GSTP1 and p16(INK4a) methylated promoters, those with a greater age had a higher RR of increased MN frequency compared with younger exposed individuals with methylated promoters. These results support the conclusion that gene-specific promoter methylation may increase MN frequency in a dependent or independent interaction with occupational exposure to organic solvents.

[Microbiologic and molecular diagnostic of cariogenic bacteria in pregnant women from the Araucania Region of Chile]. / Diagnóstico microbiológico y molecular de bacterias cariogénicas en mujeres embarazadas de la Región de La Araucanía, Chile.

Dental caries is a transmissible infectious disease in which Streptococcus mutans is a principal protagonist. Although it is widely believed that pregnancy is harmful to teeth, the effect of pregnancy on the development of caries is not clear. Considering this situation, the aim of the present study was to evaluate the levels of infection and to differentiate bacterial species with cariogenic potential in pregnant women from the Araucania region in Chile, by bacteriological and molecular analysis. In this work, we evaluated 51 pregnant women aged 15 to 40 years. The results show that 100% of women are infected by mutans streptococci Group, and 70.6% exhibited high levels of infection (> 500.000 cfu/mL). The molecular analysis shows that Streptococcus mutans and Streptococcus sobrinus frequencies were 92.1% and 1.9%, respectively. In conclusion, our data suggest that pregnant women are a high risk group for caries development.

Aracnoidismo en el Hospital Universitario Ruíz Páez estado Bolívar Venezuela: y revisión de la literatura / Arachnoidism at Hospital Universitario Ruíz Páez

El aracnoidismo constituye el síndrome producido por la mordeura de arañas. En el estado Bolívar, Venezuela, se desconoce la prevalencia de estos accidentes. El objetivo del presente estudio fue determinar la prevalencia y aspectos clínico-epidemiológicos del aracnoidismo en el Complejo Hospitalario "Ruíz Páez", centro de referencia en el Estado Bolívar, Venezuela. Se realizó un estudio descriptivo, retrospectivo. Se revisaron las historias clínicas de los casos de aracnoidismo que fueron evaluados en el Complejo Hospitalario Universitario "Ruíz Páez" de ciudad bolívar durante el período de enero 1996 a julio 2003, registrándose los datos clínicos y epidemiológicos. Además, se realizó revisión de la literatura. En el período de estudio se diagnosticaron 3 casos de aracnoidismo. En Ciudad Bolívar el aracnoidismo es inusual; suele ser leve y no complicado; sin embargo, el personal de salud debe estar atento ante eventuales envenenamientos graves en la región

[Distribution of capsular types and antimicrobial susceptibility of Streptococcus agalactiae causing infections in Argentina]. / Distribución de tipo capsular y sensibilidad antimicrobiana de Streptococcus agalactiae productores de infecciones en Argentina.

Streptococcus agalactiae is an endogenous bacterium that has emerged in the last 20 years as an etiological agent in both neonatal and perinatal infections, and in immunocompromised patients. The differentiation of the capsular polysaccharide, the presence of surface proteins c, X, R, and molecular methods allow classification in serotypes and genotypes. This identification is a useful tool for epidemiological purposes and virulence studies in this bacterium. The objective of this work was to study the serotypes and the antimicrobial susceptibility of isolates recovered from invasive diseases in different areas of Argentina. In the analyzed sample a fair predominance of Ia and III serotypes was recovered, followed by II and IV serotypes. All the isolates were found to be sensitive to penicillin. A 6% of resistance to erythromycin and a 4.5% to clindamycin were detected. In three of the isolates, constitutive MLS phenotype (resistance to macrolides, lincosamins and streptogramins) was founded, while in the remaining one, inducible MLS phenotype was detected. These results stress the importance of conducting a surveillance of the prevalent serotypes in our country with the goal of future prevention of this disease with an effective vaccine. The knowledge of the antimicrobial susceptibility profile will be also important to obtain therapeutic success in the treatment.

Distribución de tipo capsular y sensibilidad antimicrobiana de Streptococcusagalactiae productores de infecciones en Argentina / Distribution of capsular types and antimicrobial susceptibility of Streptococcus agalactiae causing infections in Argentina

Streptococcus agalactiae es una bacteria colonizante que ha emergido en los últimos años como causante de infecciones neonatales, perinatales y en pacientes con compromiso inmunológico. La caracterización del polisacárido capsular, de las proteínas de superficie (c, X, R), así como el análisis de marcadores moleculares, permiten su clasificación en serotipos y genotipos. Esto resulta de utilidad para fines epidemiológicos y para estudios de virulencia de la bacteria. El objetivo de este trabajo fue conocer los serotipos prevalentes y la sensibilidad antimicrobiana de aislamientos provenientes de procesos infecciosos en pacientes de distintas zonas de Argentina. En la muestra analizada se obtuvo predominio de los serotipos Ia y III, seguido de II y IV. Todas las cepas resultaron sensibles a penicilina. Se observó 6% de resistencia a eritromicina y 4,5% a clindamicina. En 3 de las cepas se detectó fenotipo MLS (resistencia a macrólidos, lincosaminas y estreptograminas) constitutiva y en una cepa, resistencia MLS inducible. Los resultados logrados en este estudio destacan la importancia de efectuar un relevamiento de los serotipos más frecuentes en nuestro país en vistas a la prevención de esta infección con una vacuna que realmente sea eficaz, como así también el conocimiento de la sensibilidad antimicrobiana para lograr éxito terapéutico en los tratamientos.

Streptococcus agalactiae is an endogenous bacterium that has emerged in the last 20 years as an etiological agent in both neonatal and perinatal infections, and in immunocompromised patients. The differentiation of the capsular polysaccharide, the presence of surface proteins c, X, R, and molecular methods allow classification in serotypes and genotypes. This identification is a useful tool for epidemiological purposes and virulence studies in this bacterium. The objective of this work was to study the serotypes and the antimicrobial susceptibility of isolates recovered from invasive diseases in different areas of Argentina. In the analyzed sample a fair predominance of Ia and III serotypes was recovered, followed by II and IV serotypes. All the isolates were found to be sensitive to penicillin. A 6% of resistance to erythromycin and a 4.5% to clindamycin were detected. In three of the isolates, constitutive MLS phenotype (resistance to macrolides, lincosamins and streptogramins) was founded, while in the remaining one, inducible MLS phenotype was detected. These results stress the importance of conducting a surveillance of the prevalent serotypes in our country with the goal of future prevention of this disease with an effective vaccine. The knowledge of the antimicrobial susceptibility profile will be also important to obtain therapeutic success in the treatment.

Distribución de tipo capsular y sensibilidad antimicrobiana de Streptococcus agalactiae productores de infecciones en Argentina. / [Distribution of capsular types and antimicrobial susceptibility of Streptococcus agalactiae causing infections in Argentina]

Streptococcus agalactiae is an endogenous bacterium that has emerged in the last 20 years as an etiological agent in both neonatal and perinatal infections, and in immunocompromised patients. The differentiation of the capsular polysaccharide, the presence of surface proteins c, X, R, and molecular methods allow classification in serotypes and genotypes. This identification is a useful tool for epidemiological purposes and virulence studies in this bacterium. The objective of this work was to study the serotypes and the antimicrobial susceptibility of isolates recovered from invasive diseases in different areas of Argentina. In the analyzed sample a fair predominance of Ia and III serotypes was recovered, followed by II and IV serotypes. All the isolates were found to be sensitive to penicillin. A 6

of resistance to erythromycin and a 4.5

to clindamycin were detected. In three of the isolates, constitutive MLS phenotype (resistance to macrolides, lincosamins and streptogramins) was founded, while in the remaining one, inducible MLS phenotype was detected. These results stress the importance of conducting a surveillance of the prevalent serotypes in our country with the goal of future prevention of this disease with an effective vaccine. The knowledge of the antimicrobial susceptibility profile will be also important to obtain therapeutic success in the treatment.

IgA antibodies to Chlamydia trachomatis and seminal parameters in asymptomatic infertile males.

Prevalence of IgA antibodies to Chlamydia trachomatis in semen samples from infertile men was estimated and its clinical meaning is discussed. The ejaculate of 102 infertile men without any symptom of genital infection was studied, and seminal alterations were classified according to WHO criteria. Antichlamydial IgA antibodies were detected using a solid-phase, enzyme-linked immunoassay (ImmunoComb II Chlamydia trachomatis monovalent IgA) and related to sperm count, motility and membrane integrity, seminal leucocyte count, and past history of sexually transmitted disease (STD). Prevalence of IgA antibodies to C. trachomatis was 23%. There was no relationship between IgA antibodies and the sperm variables or leucocyte count in semen. However, a strong association between antichlamydial IgA antibodies and the antecedent of STD was found (p < .005; OR = 6). IgA antibodies to C. trachomatis did not cause alterations in sperm function and they were not associated with inflammatory response. However, these antibodies in semen of asymptomatic infertile men would indicate a risk of C. trachomatis infection for the couples of those patients.

Cytogenetic effects from exposure to mixed pesticides and the influence from genetic susceptibility.

Exposure to pesticides remains a major environmental health problem. Health risk from such exposure needs to be more precisely understood. We conducted three different cytogenetic assays to elucidate the biological effects of exposure to mixed pesticides in 20 Costa Rica farmers (all nonsmokers) compared with 20 matched controls. The farmers were also exposed to dibromochloropropane during the early employment years, and most of them experienced sterility/fertility problems. Our data show that the farmers had consistently higher frequencies of chromosome aberrations, as determined by the standard chromosome aberration assay, and significantly abnormal DNA repair responses (p < 0.05), as determined by the challenge assay, but no statistically significant differences in the tandem-probe fluorescence in situ hybridization (FISH) assay (p > 0.05). Genotype analysis indicates that farmers with certain "unfavorable" versions of polymorphic metabolizing genes (cytochrome P4502E1, the glutathione S-transferases mu and theta, and the paraoxonase genes) had significantly more biological effects, as determined by all three cytogenetic assays, than both the farmers with the "favorable" alleles and the matched controls. A unique observation is that, in individuals who had inherited any of the mentioned "unfavorable" alleles, farmers were consistently underrepresented. In conclusion, the Costa Rican farmers were exposed to genotoxic agents, most likely pesticides, which expressed the induction of biological and adverse health effects. The farmers who had inherited "unfavorable" metabolizing alleles were more susceptible to genotoxic effects than those with "favorable" alleles. Our genotype data suggest that the well-recognized "healthy worker effect" may be influenced by unrecognized occupational selection pressure against genetically susceptible individuals.

In vitro and in vivo genotoxic activity of miral, an organophosphorus insecticide used in Colombia.

Miral 500 CS (CAS# 42509-80-8), an organophosphorus insecticide, has been widely used in Columbia to fumigate coffee plantations. Therefore, there is extensive human exposure to this pesticide. Miral's mutagenic and genotoxic activities, however, are not known. In this study, such activities of the pesticide were evaluated using the Salmonella TA98/S9 test and the chromosome aberration assay in bone marrow cells of Swiss albino CD1 male mice. All doses tested with Salmonella in the presence of S9 mix (3.2, 16, 80, 400 and 2000 micrograms/plate) induced a mutagenic response that was three times the spontaneous mutation frequency. The mutagenic response without S9 was twice the spontaneous frequency. Based on a 4-day treatment (i.p.) of mice with Miral, the median lethal dose (LD50) and the maximum tolerated dose (MTD) were 912.5 mg/kg and 730 mg/kg, respectively. A significant dose-dependent cell cycle delay (r2 = 0.85, p < 0.01) was observed in bone marrow cells when mice were treated for 24 h with 73, 146, 219, 292, 365, 438, 511, 584, 657 and 730 mg/kg. Significant increase in mitotic indices (p < 0.02) and chromosome aberrations (p < 0.05) were induced in bone marrow cells, when mice were treated for 18 h with the highest dose 511 mg/kg. Our results indicate that Miral is a mutagenic compound in Salmonella and is capable of inducing chromosome aberrations at high doses in mice. Additional genotoxicity studies in farmers exposed to Miral should be conducted to determine the potential human health risk resulting from chronic low-dose exposures to this pesticide.

Nucleic acid scanning-by-hybridization of enterohemorrhagic Escherichia coli isolates using oligodeoxynucleotide arrays.

Nucleic acid scanning by hybridization (NASBH) is a non-electrophoretic typing strategy that uses gridded oligonucleotides to reproducibly characterize arbitrarily amplified nucleic acid sequences. Membrane-bound arrays of terminally-degenerate oligonucleotides were hybridized to DNA amplification fingerprinting (DAF) products from enterohemorrhagic Escherichia coli O157:H7 isolates. Numerical and cluster analysis of 64 isolates, selected by DAF to represent a single dominant amplification type identified 14 hybridization types. Results show that NASBH is a powerful alternative for the identification of closely related bacteria, can be used successfully in epidemiological studies, and holds potential in general nucleic acid diagnostics.

Magnesio, calcio y fósforo séricos en neonatos de alto riesgo y controles / Serum magnesium, calcium and phosphorus in normal and high risk neonates

Las convulsiones son un problema neonatal frecuente y grave. Las principales determinaciones sugeridas para investigar su origen tiene relaión por ejemplo con la medición de los niveles de glucosa, magnesio, calcio, etc. Se estudiaron a 32 recién nacidos de alto riesgo y en un grupo control, formado por 30 neonatos sanos, los niveles de magnesio, calcio y fósforo por las metódicas de Calmagite-dye y o-Cresolftaleína-Complexona y Molibdato-Vanadato, respectivamente. Los valores en controles fueron 2,55 ñ 0,28 mg/dl para magnesio; 8,21 ñ 1,20 mg/dl para calcio y 5,96 ñ 1,18 mg/dl para fósforo y en el grupo de riesgo fueron: 2,39 ñ 0,41 mg/dl; 8,21 ñ 1,32 mg/dl y 5,87ñ 1,14 mg/dl. El grupo de riesgo evidenció valores más bajos para magnesio con una mayor dispersión, siendo esto significativo para la prueba de F con un p<0,05. También se observaron niveles levemente más altos de calcio en este grupo, con mayor dispersión de valores pero, no siendo significativas estas diferencias. Los valores de fósforo en ambos grupos fueron muy similares. Se concluye que solamente el magnesio podría ser un indicador sensible ante la presencia de convulsiones, aunque deberían estudiarse estos parámetros conjuntamente con los niveles de glicemia

[Labial melanotic macule. Review of the literature. Report of a case]. / Macula melanotica labial. Revision de la literatura. Presentation de un caso.

A review of the literature is done concerning labial melanotic macule. Several aspects are studied such as definition, clinical significance and histopathology. A new case is added, located in the lower lip. Several observations are done and conclusions are drawn. Emphasis is given to the need of determining the etiology of the lesion.

Brote Intrahospitalario de Salmonelosis por Salmonella Enteritidis Seropo Agona / Nosocomial Salmonellosis Outbreak by Salmonella Enteritidis, Agona Type

Se describe una epidemia de salmonelosis ocurrida en el servicio de Pediatria del Hospital Militar Central, la cual afecto a quince pacientes. Se concluye que fue una infeccion intrahospitalaria. Como agente etiologico fue plenamente identificado Salmonella Enteritidis, serotipo Agona con una gran multirresistencia a los antibioticos. Como origen posible del brote se demostro un portador sano, preparador de teteros en el servicio. Es, posiblemente, la primera vez que se informa Salmonella Agona en nuestro pais