ESBL-producing Escherichia coli and Klebsiella pneumoniae from health-care institutions in Mexico.

We investigated the phenotypic and molecular characteristics of Extended-Spectrum-ß-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae clinical isolates from four health-care institutions in Hermosillo, Sonora, Mexico. ESBL-producing isolates were collected from February to August 2016. The prevalence of ESBL-producing E. coli and K. pneumoniae was 11.9 and 8.7%, respectively. High dissemination of resistance to ciprofloxacin (88%), trimethoprim/sulfamethoxazole (72%) and aminoglycosides (59%) were detected, as well as susceptibility to meropenem, amikacin and tigecycline. The ESBL found variants were CTX-M-1 (88%) and CTX-M-9 (5%). The plasmid-mediated quinolone resistance (PMQR) gene aac(6´)-Ib-cr was identified in 62% of a representative sample, whereas the qnrB and qnrS genes were detected in 49% of the isolates. PFGE analyses detected many unrelated clones among the hospital or community isolates. A constant programme of epidemiological surveillance is recommended to understand the dynamics of bacterial resistance to both cephalosporin as well as the fluoroquinolone family of antibiotics.

Antiproliferative activity of spinasterol isolated of Stegnosperma halimifolium (Benth, 1844).

Cancer is the major cause of death in the world, representing a significant public health problem. Plants have been shown as a great source of secondary metabolites with anticancer activity. The aim of this work was evaluated the antiproliferative activity of the methanolic extracts, chemical fractions and the compound spinasterol isolated of medicinal plant Stegnosperma halimifolium. The methanolic extracts of stem, leaf and stem/leaf was obtained by maceration. The methanolic extract of stem was purified by successive extractions with solvents as n-hexane, ethyl acetate and ethanol. The n-hexane fraction was separated by column chromatographic and monitored by thin layer chromatographic. The compound spinasterol was characterized by 1H NMR, 13C NMR and Mass Spectrometry. Methanolic extracts, chemical, chromatographic fractions and spinasterol was evaluated against RAW 264.7, M12.C3.F6, PC-3, LS-180, A549 and HeLa cancer cell lines by the standardized method MTT for determinate the antiproliferative activity. Methanolic extract of stem shown the better antiproliferative activity against the murine macrophage cancer cell line RAW 264.7. n-Hexane chemical fraction shown antiproliferative activity against human alveolar cancer cell line A549 and RAW 264.7. Was isolated and characterized a compound by NMR 1H and 13C, revealing the presence of sterol spinasterol. Spinasterol shown to have antiproliferative activity against cervical cancer cell line HeLa and RAW 264.7, indicating that spinasterol can be a responsible compound of antiproliferative activity found in the methanolic extract of Stegnosperma halimifolium.

Proposal of a Screening MIRU-VNTR Panel for the Preliminary Genotyping of Mycobacterium bovis in Mexico.

Mycobacterium bovis is the major causative agent of bovine tuberculosis, one of the most relevant zoonoses in the world, and affects a wide range of wild and domesticated animals. Development of screening panels in mycobacterial genotyping, according to specific geographical regions, is strongly needed. The aim of this study is to select a panel, constituted by highly polymorphic MIRU-VNTR loci, to discriminate clinical isolates of M. bovis in Mexico. In this study, 65 isolates of M. bovis obtained from clinical bovine samples proceeding from different geographic regions of Mexico were identified by phenotypic and genotypic tests and subsequently genotyped by a 24-locus MIRU-VNTR panel. The most polymorphic loci were selected to build a panel with a high discriminatory power similar to the 24-locus panel results. A panel of seven elements (QUB 11a, MIRU 26, ETR-A, QUB 26, MIRU 16, MIRU 27, and MIRU 39) with the highest allelic diversity showed an appropriate differentiation. The selected MIRU-VNTR elements, according to the regional allelic variability, may be used in the preliminary genotyping of Mycobacterium bovis isolates in Mexico.

In vitro anti-mycobacterial activity of nine medicinal plants used by ethnic groups in Sonora, Mexico.

BACKGROUND: Sonoran ethnic groups (Yaquis, Mayos, Seris, Guarijíos, Pimas, Kikapúes and Pápagos) use mainly herbal based preparations as their first line of medicinal treatment. Among the plants used are those with anti-tuberculosis properties; however, no formal research is available. METHODS: Organic extracts were obtained from nine medicinal plants traditionally used by Sonoran ethnic groups to treat different kinds of diseases; three of them are mainly used to treat tuberculosis. All of the extracts were tested against Mycobacterium tuberculosis H37Rv using the Alamar Blue redox bioassay. RESULTS: Methanolic extracts from Ambrosia confertiflora, Ambrosia ambrosioides and Guaiacum coulteri showed minimal inhibitory concentration (MIC) values of 200, 790 and 1000 µg/mL, respectively, whereas no effect was observed with the rest of the methanolic extracts at the concentrations tested. Chloroform, dichloromethane, and ethyl acetate extracts from Ambrosia confertiflora showed a MIC of 90, 120 and 160 µg/mL, respectively. CONCLUSIONS: A. confertiflora and A. ambrosioides showed the best anti-mycobacterial activity in vitro. The activity of Guaiacum coulteri is consistent with the traditional use by Sonoran ethnic groups as anti-tuberculosis agent.For these reasons, it is important to investigate a broader spectrum of medicinal plants in order to find compounds active against Mycobacterium tuberculosis.

Antibacterial activity of Sonoran propolis and some of its constituents against clinically significant Vibrio species.

The aim of the present study was to evaluate the anti-Vibrio activity of propolis collected from three different areas of the Sonoran Desert in northwestern, Mexico [Pueblo de Alamos (PAP), Ures (UP), and Caborca (CP)]. The anti-Vibrio spp. activity of Sonoran propolis was determined by the broth microdilution method. UP propolis showed the highest antibacterial activity [minimal inhibitory concentration (MIC(50))<50 µg mL(-1)] against Vibrio spp. (UP>CP>PAP). UP propolis significantly inhibited the growth of Vibrio cholerae O1 serotype Inaba (MIC(50)<50 µg mL(-1)), V. cholerae non-O1 (MIC(50)<50 µg mL(-1)), V. vulnificus (MIC(50)<50 µg mL(-1)), and V. cholerae O1 serotype Ogawa (MIC(50) 100 µg mL(-1)), in a concentration-dependent manner. The UP propolis constituents, galangin and caffeic acid phenethyl ester (CAPE), exhibited a potent growth inhibitory activity (MIC(50) 0.05-0.1 mmol l(-1)) against V. cholerae strains (non-O1 and serotype Ogawa). The strong anti-Vibrio activity of Sonoran propolis and some of its chemical constituents (galangin and CAPE) support further studies on the clinical applications of this natural bee product against different Vibrio spp., mainly V. cholerae.

[Hospital and community-acquired ß-lactamases-producing Escherichia coli and Klebsiella pneumoniae at hospitals in Hermosillo, Sonora]. / Escherichia coli y Klebsiella pneumoniae comunitarias y hospitalarias productoras de ß-lactamasas en hospitales de Hermosillo, Sonora.

OBJECTIVE: To determine the prevalence of extended-spectrum ß-lactamases (ESBL)-producing Esherichia coli and Klebsiella pneumoniae in hospitals of Hermosillo, Sonora, Mexico. MATERIAL AND METHODS: To detect ESBL-production, 1 412 bacterial isolates obtained over a one year period (2008-2009) were analyzed using the double-disk synergy test, with and without clavulanic acid. RESULTS: Hospitalaryacquired ESBL-producing E.coli and K.pneumoniae (31.8% and 35.3%) were isolated with higher prevalence that community-acquired isolates (14.4% and 0.0%) (p<0.005). CONCLUSIONS: Our study shows the presence of ESBL-producing bacteria in the three hospitals.

Escherichia coli y Klebsiella pneumoniae comunitarias y hospitalarias productoras de β-lactamasas en hospitales de Hermosillo, Sonora / Hospital and community-acquired β-lactamases-producing Escherichia coli and Klebsiella pneumoniae at hospitals in Hermosillo, Sonora

OBJETIVO: Determinar la prevalencia de Escherichia coli y Klebsiella pneumoniae productoras de β-lactamasas de espectro extendido (BLEE) en hospitales de Hermosillo, Sonora, México. MATERIAL Y MÉTODOS: Se analizaron 1 412 aislamientos obtenidos durante un año (2008-2009). La detección de productores de BLEE se realizó por el método de sinergia de doble disco con y sin ácido clavulánico. RESULTADOS: Se aislaron E.coli y K.pneumoniae productores de BLEE hospitalarios (31.8 y 35.3 por ciento) con mayor prevalencia que los comunitarios (14.4 y 0.0 por ciento) (p<0.005). CONCLUSIONES: Nuestro estudio demuestra la presencia de microorganismos productores de BLEE en los tres hospitales.

OBJECTIVE: To determine the prevalence of extended-spectrum β-lactamases (ESBL)-producing Esherichia coli and Klebsiella pneumoniae in hospitals of Hermosillo, Sonora, Mexico. MATERIAL AND METHODS: To detect ESBL-production, 1 412 bacterial isolates obtained over a one year period (2008-2009) were analyzed using the double-disk synergy test, with and without clavulanic acid. RESULTS: Hospitalaryacquired ESBL-producing E.coli and K.pneumoniae (31.8 percent and 35.3 percent) were isolated with higher prevalence that community-acquired isolates (14.4 percent and 0.0 percent) (p<0.005). CONCLUSIONS: Our study shows the presence of ESBL-producing bacteria in the three hospitals.