[Prevalence of vaginal candidiasis in pregnant women. Identification of yeasts and susceptibility to antifungal agents]. / Prevalencia de candidiasis vaginal en embarazadas. identificación de levaduras y sensibilidad a los antifúngicos.

Pregnant women are more susceptible to both vaginal colonization and infection by yeast. Our objectives were to determine the prevalence in pregnant women of yeasts isolated from vaginal exudates and their susceptibility to current antifungal drugs. A total of 493 patients was studied between December 1998 and February 2000. The prevalence of Candida spp. was 28% (Candida albicans 90.4%; Candida glabrata 6.3%; Candida parapsilosis 1.1%, Candida kefyr 1.1 %; unidentified species 1.1 %). The diffusion test in Shadomy agar was employed to determine the susceptibility to fluconazole, ketoconazole, itraconazole and nistatine. All C. albicans, C. kefyr and C. parapsilosis isolates were susceptible in vitro to the antifungal agents tested, while 1 in 6 C. glabrata isolates showed resistance to azole drugs; all strains were susceptible to nistatine. In pregnant women, C. albicans was the yeast most frequently isolated from vaginal exudates; it continues to be highly susceptible to antifungal drugs. Azole resistance was detected only among C. glabrata isolates. Identification to the species level is recommended, specially in cases of treatment failure and recurrent or chronic infection.

Prevalencia de candidiasis vaginal en embarazadas: Identificación de levaduras y sensibilidad a los antifúngicos / Prevalence of vaginal candidiasis in pregnant women: Identification of yeasts and susceptibility to antifungal agents

La mujer embarazada es más susceptible tanto a la colonización como a la infección vaginal por levaduras. El objetivo de este trabajo fue determinar la prevalencia de levaduras aisladas de exudados vaginales de mujeres embarazadas y evaluar la sensibilidad a los antifúngicos de uso frecuente. Se estudiaron 493 pacientes en el período comprendido desde diciembre de 1998 hasta febrero de 2000. La prevalencia de Candida spp. fue 28% (Candida albicans 90,4%, Candida glabrata 6,3%, Candida parapsilosis 1,1%, Candida kefyr 1,1%, especies no identificadas 1,1%). Se determinó la sensibilidad a fluconazol, ketoconazol, itraconazol y nistatina por el método de difusión en agar Shadomy. Todos los aislamientos de C. albicans, C. kefyr y C. parapsilosis fueron sensibles in vitro a los antifúngicos probados, mientras que 1 de 6 aislamientos de C. glabrata presentó resistencia extendida a todos los azoles, pero sensibilidad a nistatina. En mujeres embarazadas C. albicans fue la levadura más frecuentemente aislada de exudados vaginales y continúa siendo ampliamente sensible a los antifúngicos; sólo en C. glabrata se observó resistencia a los azoles. Se recomienda la identificación de la levadura a nivel de especie particularmente en el caso de falla terapéutica y en infecciones recidivantes o crónicas.

Pregnant women are more susceptible to both vaginal colonization and infection by yeast. Our objectives were to determine the prevalence in pregnant women of yeasts isolated from vaginal exudates and their susceptibility to current antifungal drugs. A total of 493 patients was studied between December 1998 and February 2000. The prevalence of Candida spp. was 28% (Candida albicans 90.4%; Candida glabrata 6.3%; Candida parapsilosis 1.1%, Candida kefyr 1.1%; unidentified species 1.1%). The diffusion test in Shadomy agar was employed to determine the susceptibility to fluconazole, ketoconazole, itraconazole and nistatine. All C. albicans, C. kefyr and C. parapsilosis isolates were susceptible in vitro to the antifungal agents tested, while 1 in 6 C. glabrata isolates showed resistance to azole drugs; all strains were susceptible to nistatine. In pregnant women, C. albicans was the yeast most frequently isolated from vaginal exudates; it continues to be highly susceptible to antifungal drugs. Azole resistance was detected only among C. glabrata isolates. Identification to the species level is recommended, specially in cases of treatment failure and recurrent or chronic infection.

[Deoxyribonuclease activity detection in Clostridium chauvoei strains]. / Detección de la actividad de desoxiribonucleasa (DNasa) en cepas de Clostridium chauvoei.

Beta toxin of C. chauvoei has desoxiribonuclease (DNase) activity which is regarded as one of its virulence factors. The production of DNase was detected in strains isolated from bovines, using as controls C. chauvoei ATCC 10092, and C. perfringens Type A and C. septicum, both laboratory isolates. The enzyme activity was made evident on a DNA substrate observing the macroscopic degradation. A simple methodology was developed using a commercial medium for DNase test, with the incorporation of sterile horse serum. Each strain was streaked on the surface of the medium, incubated in anaerobic atmosphere at 37 degrees C for 48 hours. The plates were revealed with HCI 1 N. The appearance of a clear and transparent zone around and under the microbial growing was considered a positive reaction. Enzyme activity was detected in 10 of 12 strains and also in the controls. The serum addition to the commercial basal medium allows the optimum development of the microorganism showing the enzymatic digestion zone.

Detección de la actividad de desoxiribonucleasa (DNasa) en cepas de Clostridium chauvoei / [Deoxyribonuclease activity detection in Clostridium chauvoei strains]

Beta toxin of C. chauvoei has desoxiribonuclease (DNase) activity which is regarded as one of its virulence factors. The production of DNase was detected in strains isolated from bovines, using as controls C. chauvoei ATCC 10092, and C. perfringens Type A and C. septicum, both laboratory isolates. The enzyme activity was made evident on a DNA substrate observing the macroscopic degradation. A simple methodology was developed using a commercial medium for DNase test, with the incorporation of sterile horse serum. Each strain was streaked on the surface of the medium, incubated in anaerobic atmosphere at 37 degrees C for 48 hours. The plates were revealed with HCI 1 N. The appearance of a clear and transparent zone around and under the microbial growing was considered a positive reaction. Enzyme activity was detected in 10 of 12 strains and also in the controls. The serum addition to the commercial basal medium allows the optimum development of the microorganism showing the enzymatic digestion zone.

Detección de la actividad de desoxiribonucleasa (DNasa) en cepas de Clostridium chauvoei. / [Deoxyribonuclease activity detection in Clostridium chauvoei strains]

Beta toxin of C. chauvoei has desoxiribonuclease (DNase) activity which is regarded as one of its virulence factors. The production of DNase was detected in strains isolated from bovines, using as controls C. chauvoei ATCC 10092, and C. perfringens Type A and C. septicum, both laboratory isolates. The enzyme activity was made evident on a DNA substrate observing the macroscopic degradation. A simple methodology was developed using a commercial medium for DNase test, with the incorporation of sterile horse serum. Each strain was streaked on the surface of the medium, incubated in anaerobic atmosphere at 37 degrees C for 48 hours. The plates were revealed with HCI 1 N. The appearance of a clear and transparent zone around and under the microbial growing was considered a positive reaction. Enzyme activity was detected in 10 of 12 strains and also in the controls. The serum addition to the commercial basal medium allows the optimum development of the microorganism showing the enzymatic digestion zone.

Incidence of Chlamydia trachomatis and other potential pathogens in neonatal conjunctivitis.

OBJECTIVE: Ocular infection in neonatology is a permanent and important health problem. To improve primary attention, prevention, and control, the study of the potential bacterial etiology of all consecutive cases of conjunctivitis was incorporated as a regular procedure in primary care from July 1995 to December 1998. MATERIALS AND METHODS: Prof. A. Posadas Hospital (Great Buenos Aires) has an average of 4294 births per year. This report analyzes the results obtained in 332 infants (age range, 0-30 d) with conjunctivitis. Clinical conjunctivitis was diagnosed in inpatients and outpatients by the same specialized staff. Isolation and characterization of bacteria were done by conventional microbiologic methods, including specific search for Neisseria gonorrhoeae and Chlamydia trachomatis. Chlamydia trachomatis was studied by antigen immunodetection and polymerase chain reaction, and genotyped by restriction fragment length polymorphism. RESULTS: Conjunctivitis had an incidence (cases per 1000 live births) of 39.6 in 1995, 25.3 in 1996, 15.4 in 1997, and 15.2 in 1998. Microbial growth was detected in 167 (50.3%) of 332 cases. Ocular C. trachomatis infection was detected in 26 cases (7.83%). Five of seven isolates in tissue cultures belonged to type E and two to type G. Bacteria from respiratory ecology were the main isolates: Haemophilus influenzae (16.9%), Streptococcus pneumoniae (12.3%), and Staphylococcus aureus (8.7%). Haemophilus influenzae isolates were not serotyped and 17.2% of them were b-lactamase producers. In 15 cases both H. influenzae and S. pneumoniae were isolated together. Of S. pneumoniae, 4.9% were oxacillin resistant. CONCLUSIONS: There has been a decline in the total number of cases of neonatal conjunctivitis, but the disease is still an important health problem. Chlamydia trachomatis also shows a decreasing profile with an incidence of (cases per 1000 live births) 4.39 in 1995, 1.85 in 1996, 1.01 in 1997, and 0.78 in 1998, and a tendency to show more incidence in spring-summer and significant accumulation of cases in babies between 7 and 9 days of age. Haemophilus influenzae alone (12.3%) or associated with S. pneumoniae (4.5%) appears as a prevalent potential bacterial pathogen. A significant accumulation of H. influenzae and S. pneumoniae cases occurs in winter. In 47.6% of cases, there was no bacterial growth. No significant seasonal differences in percentage of negative cultures or among the three-day age groups were detected. Neisseria gonorrhoeae was not found associated with ophthalmia neonatorum in this series.

Antiviral activity of enterocin CRL35 against herpesviruses.

Enterocin CRL35 is an antibacterial polypeptide of 3.5 x 10(3) Da produced by Enterococcus faecium CRL35. A series of experiments are described that show the enterocin also had antiviral activity against thymidine-kinase positive (tk+) and deficient (tk-) strains of herpes simplex (HSV) type 1 and 2 in Vero and BHK-21 cells. This activity was observed at 100 microg/ml, 15-fold lower than the cytotoxic concentration. In both cell lines there was a 2 log inhibition of infectivity. The compound inhibited viral multiplication in a dose-dependent manner and had no virucidal effect. Enterocin CRL35 also inhibited the virion-associated host shutoff in infected Vero cells showing that intracellular viral multiplication was affected.

Detection of the etx gene (epsilon-toxin inducer) in plasmids of high molecular weight in Clostridium perfringens type D.

The purpose of this work is to correlate the production of epsilon-toxin in a set of strains of Clostridium perfringens type D with the presence of the etx gene, either genomic or in plasmids. Total DNA obtained from strains with a different level of toxin production was explored by PCR and all the strains showed the amplification signal. Different methods were used to obtain plasmid profiles and all of the bands were assayed by PCR. The detection of the etx gene was only shown in several high molecular plasmids. These results were confirmed by a Southern blot. We suggest that the localization of the etx gene in different plasmids could be associated with the epsilon-toxin production level.

[Syphilis in adolescent mothers in the city of Posadas, Province of Misiones]. / Sifilis en madres adolescentes en la ciudad de Posadas, Provincia de Misiones.

During three months (April to June 1997) 1,238 consecutive pregnant women were studied at the time of delivery at the Madariaga public Hospital. Syphilis was confirmed in 26 (2.1%) women, and 15 cases (57.7%) of congenital syphilis were demonstrated in newborns one of whom was a stillborn. Of the syphilitic women 61.5% were 20 years old (average), 65.4% were single, 19.2% had a stable partner and 15.4% were married; 70% of them had finished elementary school (seven years), but despite this discrete level of instruction and that they were benefited with free health attention, 73% of them had not started or completed the pregnancy control. None of these women acted as sexual workers or were drug users; 57.7% were unemployed and the remainder worked as domestic servants or were still going to school. Menarca started at 13 (average) and the age of the first sexual activity was 15 (average). The distribution of the cases of syphilis within the city area shows four clusters that coincide with the lower income population, but not with marginal groups. The failure to submit to medical control during pregnancy among syphilitic women is directly linked with an increased risk for congenital syphilis. The specific prevalence of syphilis in women (20 years old or less) pregnant or not, shows an alarming hidden epidemic situation. An interinstitutional and communitary program, with direct interventions within the detected population clusters, is now underway in order to control syphilis. Undesired pregnancy and syphilis seem to be associated with adolescent unsafe sex conducts. A coordinated program between Public Health Service and National Misiones University is operating, visiting home by home, in order to decrease or eliminate congenital syphilis and is considered a priority health problem. Unfortunately, if sexual conducts do not undergo changes in the near future, at least by the correct use of condoms, HIV will replace syphilis.

Flagellin, a major protein present in SDS-PAGE profiles of Sarkosyl-OMP-enriched fractions from Bordetella bronchiseptica Bvg- or modulated Bvg+ strains.

The bvg or vir locus positively regulates the expression of many Bordetella virulence-associated determinants (encoded by vag genes), including cell envelope proteins, in response to environmental stimuli. On the other hand, several genes named vrg genes are negatively controlled by the bvg regulon (Knapp and Mekalanos, 1988). Flagellin is encoded by a vrg gene, which is expressed when the principal virulence factors are eliminated during antigenic modulation or in phase variants (Akerley et al., 1992). We have previously analyzed SDS-PAGE profiles of Sarkosyl-outer membrane protein (OMP)-enriched fractions from B. bronchiseptica Bvg- and modulated Bvg+ strains and reported a major band associated with the avirulent phenotype (Passerini de Rossi et al., 1995). In order to characterize this band we have purified flagellar filaments from Bvg- and modulated Bvg+ strains, and analyzed them by SDS-PAGE. These profiles revealed a single major band of 40 or 45 kDa depending on the strain. The N-terminal amino acid sequence of the putative flagellin expressed by BB7200a was identical over the first 21 residues analyzed to that of the flagellin from the modulated strain BB7865 reported by Akerley et al. (1992). Comparison of the SDS-PAGE profile of flagellar filaments with that of the OMP-enriched fraction of the corresponding strain showed that the flagellum-associated polypeptide had the same electrophoretic mobility as that of the characteristic band of the avirulent phenotype. Furthermore, this band was absent in the OMP-enriched fraction profile from a Bvg- strain subjected to a treatment that removes flagella. Our results indicate that the major protein observed in SDS-PAGE profiles of Sarkosyl-OMP-enriched fractions from B. bronchiseptica Bvg- and modulated Bvg+ strains corresponds to flagellin.

[Selection of Bvg- variants of Bordetella pertussis]. / Selección de variantes Bvg- de Bordetella pertussis.

Bordetella pertussis virulent strains (Bvg+) produce a wide array of virulence factors. The production of these factors is coordinately regulated by the locus bvg in response to environmental signals in a process known as antigenic modulation. Mutations in the bvg locus originate avirulent variants (Bvg-) that are unable to express virulence factors regardless of growth conditions. In this paper we have obtained spontaneous variants Bvg- of B. pertussis Tohama I and 10536, which would be useful for studying virulence markers, using the selective media Stainer-Scholte agar supplemented with 1% Casamino-acids (SSA-CAS) and Jones-Kendrick with 0.20 microgram of erythromycin per ml (JK-Ery). We have also studied the efficiency of plating of B. pertussis Tohama I, 10536 and 40103 cells (Bvg+ strains) and of Bvg- strain 347 (control of the avirulent phenotype) on SSA-CAS and Stainer-Scholte agar (SSA), and we have analyzed the phenotype of the cells recovered from these media. The bacterial phenotype was characterized by using the following virulence markers: hemolysis production, hemagglutinin production, and outer membrane protein (OMP) enriched profiles. The three Bvg+ strains showed different behaviour in these selective media. B. pertussis Tohama I and 10536 could not be recovered on SSA, whereas on SSA-CAS the efficiency of plating was poor, less than 0.001%, but nevertheless allowed the selection of stable Bvg- variants of Tohama I since the OMP profile of this stain did not change after subculture in Cyclodextrin liquid medium. By contrast, strain 10536 grown on SSA-CAS suffered the process of antigenic modulation since this strain recovered the virulent phenotype when it was subcultured in Bordet-Gengou. Stable Bvg- variants from Tohama I and 10536 were obtained on JK-Ery. On the other hand, Bvg+ strain 40103 showed a high efficiency of plating on SSA and SSA-CAS and retained the virulent phenotype in all the selective media. Bvg- strain 347, in spite of being an avirulen variant, showed a poor efficiency of plating in SSA and a scant growth in JK-Ery, in agreement with the findings of other investigators which suggest that not all avirulent strains posses the ability to grow on media that inhibit most of virulent strains.

[Extent of endemic Chlamydia trachomatis in the metropolitan area of Buenos Aires (Argentina)]. / Dimensión de la endemia por Chlamydia trachomatis en el área de la ciudad de Buenos Aires (Argentina).

BACKGROUND: In this report we inform laboratory results accumulated over ten years (1986-1995). The number of cases, and the geographic distribution, allow us to present a very reliable data about the dimension of Chlamydia trachomatis urogenital infections in Buenos Aires city and we also compare this profile with the prevalence of Neisseria gonorrhoeae in the same area and period of time. METHODS: Patients were females and males (aged from 15 to 49 years old) attending clinics not specialize in Sexually Transmitted Diseases (STD). Intent to isolation of C. trachomatis was done in McCoy cells culture. Patients for Neisseria gonorrhoeae investigation were a population assisted at the Clinic for STD of an University Hospital (aged from 15 to 75 years old). Study for detection of N. gonorrhoeae was developed by direct and conventional culture technics. RESULTS: 4128 endocervical samples from women with lower genital tract pathology were studied and C. trachomatis infection was detected in 25.6 +/- 4.8%. Over 1206 male urethral samples 29.5 +/- 4.47% shows positive cultures. Except for years 1989 and 1990 in which annual percentage of infected women showed slightly higher percentage over the global average, the results shows a very stable annual values, as it was also found in male patients. Infection in males shows a discrete tendency to be higher compare with values obtained in women. Global results of the evolution of prevalence of N. gonorrhoeae infection shows a very different pattern. Since 1992 we demonstrate a very significant decrease in the number of confirmed cases. CONCLUSIONS: We concluded that patients not attending a STD clinic, reveal a high and very stable endemic level of C. trachomatis lower tract urogenital infections. N. gonorrhoeae in this population is a very sporadic or null finding. Prevalence of Chlamydial infection in STD centers is even higher and also shows an stable profile. In people attending STD clinics N. gonorrhoeae shows a very different kinetics, with an important decrease in prevalence in the last five years.

[Genomic heterogeneity of hepatitis B virus, genotype A circulating in the metropolitan area of Buenos Aires, Argentina]. / Heterogeneidad genómica de virus de la Hepatitis B, Genotipo A, circulantes en el área metropolitana de Buenos Aires, Argentina.

HVB DNA was extracted from highly purified Dane particles, from sera of HBV viremic patients, collected in the metropolitan area of Buenos Aires (Argentina). HBV DNA was cloned in pUC18 vector, amplified in Escherichia coli DH5 F'. Plasmids were recovered and analyzed for HBV DNA inserts. Three recombinant plasmids, pHB4, pHB7 and pHB20 were selected, and HBVDNA inserts sequenced. The resulted sequences were incorporated at the GenBank, with the following accession numbers: PHB4P3=U33188; PHB4P5=U33189; PHB7P3=U33190; PHB7P5=U33191 and PHB20=U33190; PHB7P5=U33191 and PHB20=U33187. All belongs to the genotype A, pHB4 and pHB20 have a very close relation in between each other and with L13994 sequence, from North America origin. pHB7 have a significant distance from pHB4 and pHB20 and have a discrete homology with m57633 detected in Philippines. pHB4 shows a mutation at the T 3182-Leu in the preS1 region that change Pro for Leu, this mutation is absent in 125 sequences selected (having a 65% or more of homology) from NCBI by Blast algortm. The sequence of the pre C regions of all three inserts do not show any evidence to belong to the e-or scape mutants. Type A genotypes shows to be common in the area, but a hight degree of divergence have been demonstrate between two circulating strains.

Meliacine, an antiviral compound from Melia azedarach L., inhibits interferon production.

A glycopeptide isolated from the high plant Melia azedarach L. (meliacine) inhibits the in vitro replication of several RNA and DNA animal viruses. Interferon (IFN) production was depressed greatly in meliacine treated L929 cells and primary mouse embryo fibroblast cultures (MEF) induced with Newcastle disease virus (NDV) or poly(rI).poly(rC). This action was observed when meliacine was added before, simultaneously or early after induction with poly(rI).poly(rC) or NDV. In addition, accumulation of acid-resistant IFN was strongly diminished in adult mice treated intraperitoneally with meliacine. Though meliacine causes a strong inhibition of IFN both in vitro and in vivo, we do not know how selectively it affects the IFN system.

Participation of PBP 3 in the acquisition of dicloxacillin resistance in Listeria monocytogenes.

Purified membranes of Listeria monocytogenes ATCC 15313 contain at least five penicillin-binding proteins. In two dicloxacillin-resistant mutants, derived from a sensitive parent strain, a 16-fold increase in the MIC of dicloxacillin was observed. A less-significant increase was detected in the MICs of other beta-lactam drugs. In the mutants, PBP 3 lost its strong affinity for dicloxacillin, but remained fully susceptible to binding of 125I-penicillin X, as compared with the wild-type strain. PBP 2 could not be detected in one of the mutants. No decrease in affinity for the radioactive tracer or dicloxacillin was detected in any other PBP of the resistant mutants.

[Viability of Bacillus subtilis auxotrophs in the absence of their essential metabolites]. / Viabilidad de Bacillus subtilis auxotrofos en ausencia de sus metabolitos esenciales.

The effect of tryptophan and uracil starvation on the viability of the transformant B. subtilis BSA 170 trp- ura- and its parent strains Bacillus subtilis PB 168 trp -C and Bacillus subtilis PB 3308 ura- was examined. These studies were performed at the conditions for competence development, during 16 hours. Our results showed that B. subtilis BSA 170 was resistant to tryptophan-less death during all the assay and was also resistant to uracil-less death during three hours. After this time, viability measurements revealed less colony forming units per milliliter, and decrease of the culture absorbances. The uracil-less death required the presence of tryptophan suggesting that protein synthesis is needed. The parental strains exhibit similar behavior. Bacillus subtilis PB 168 was resistant to tryptophan-less death and B. subtilis PB 3308 showed decrease of the viability after uracil starvation comparable to that of the transformant strain.