Time filter

Source Type

Alburquenque C.,Laboratorio Clnica Dvila | Alburquenque C.,University Mayor | Bucarey S.A.,University of Chile | Neira-Carrillo A.,University of Chile | And 4 more authors.
Medical Mycology | Year: 2010

Chitosan is a natural polymer derived from chitin, a structural component of fungi, insects and shrimp, which exerts antimicrobial effects against bacteria and fungi. The aim of this study was to investigate the in vitro antifungal activity of low molecular weight chitosan (LMWC), and the potential synergy between chitosan and a currently used antifungal drug, fluconazole. The in vitro minimal inhibitory concentrations (MICs) of chitosan and fluconazole against 105 clinical Candida isolates were measured by the broth microdilution method. LMWC exhibited a significant antifungal activity, inhibiting over 89.9% of the clinical isolates examined (68.6% of which was completely inhibited). The species included several fluconazole-resistant strains and less susceptible species such as C. glabrata, which was inhibited at a concentration of 4.8 mg/l LMWC. Although some strains were susceptible at pH 7.0, a greater antifungal activity of LMWC was observed at pH 4.0. There was no evidence of a synergistic effect of the combination of LMWC and fluconazole at pH 7.0. This is the first report in which the antifungal activity of LMWC was investigated with clinical Candida strains. The use of LMWC as an antifungal compound opens new therapeutic perspectives, as the low toxicity of LMWC in humans supports its use in new applications in an environment of pH 4.04.5, such as a topical agent for vulvovaginal candidiasis. © 2010 ISHAM.

Montalvo M.T.,University of Tarapaca | Lobato I.,University of Tarapaca | Villanueva H.,University of Tarapaca | Borquez C.,University of Tarapaca | And 4 more authors.
Oncology Letters | Year: 2011

Cervical cancer is the second most prevalent female cancer worldwide. The majority of cases appear between the age of 30 and 50. Human papillomavirus (HPV) plays a central role in cervical cancer with 99.7% of HPV DNA identified in invasive cervical carcinomas. The prevalence of the HPV infection varies substantially among countries and according to age and lifestyle. HPV is a common sexually transmitted infection among males and females with a 70% higher incidence in sexually active females. This study aimed to determine the prevalence of human papillomavirus in young university women by analyzing the correlation between Papanicolaou (PAP)-stained cervical tests and HPV detection by genotyping, as well as other risk factors. A total of 200 women aged between 18 and 25 years were enrolled in this study, which took place between September 2008 and May 2009 at the Universidad de Tarapacá, Arica, Chile. Results of the PAP smears showed that 97.5% of cells had normal characteristics, although an inflammatory pattern was noted. The prevalence of generic HPV infection was 3.5% when testing for HPV DNA using the polymerase chain reaction (PCR) method. An analysis of the genotype of infected female individuals indicated that high-risk HPV types, such as HPV 16 and 31 were present in 42.84 and 14.29% of females, respectively, and low-risk types such as HPV 6, in 14.29%. Only one sample with differentiated non-HPV (14.29%) was found. A 95% correlation between PAP-stained cervical tests and the method of testing for HPV was observed. Using the PCR method, it was found that of the 195 negative PAP smears, 5 were positive for HPV and two of the samples that were positive for ASC-US were also positive. A significantly increased (P<0.05) HPV infection risk was observed in the 18-21 age group with a higher prevalence (71.40%) when compared to the 22-25 age group (28.6%). A significant (P<0.042) difference was found between smoking and HPV infection. In conclusion, a significant (P<0.05) correlation was found between PAP and PCR methods for HPV testing in young university women. A significant correlation between smoking and HPV was detected, whereas no difference was noted with other parameters.

Tapia Silva R.,Major University | Valenzuela Aranguiz V.,Major University | Zamorano Pino X.,Major University | Baena Aguila R.,University Mayor
Avances en Odontoestomatologia | Year: 2010

It's usual in dental practice, to build temporary crowns using self curing acrylics; this way, important amounts of heat are generated during the polimerization process, that may affect the biological preparations. The aim of this research is to know exactly how much heat is generated during polimerazation of some resins and evaluate the relationship between resin volume and temperature rising. This research used self curing resins of three different commercial brands ALIKE™, DURALAY y MARCHE. This brands was used in volumes of: 0.25, 0.5, 1.0 and 1.5 cc. A thermocouple was connected to a digital thermometer to register temperature variations inside the material. Our results showed that the reaction heat is directly proportional to the resin volume used. ALIKE raises the largest temperature for 0.25, 0.5 and 1.0 cc. (40.6, 61.5, and 69.4°C respectly). For 1.5 cc. DURALAY showed the highest temperature at 86.0°C. Using ANOVA was found important differences in heat generation between MARCHE and ALIKE only for 0.25 cc group of samples (p=0.001).

Higuera C M.,University of Chile | Higuera C M.,University Mayor | Higuera C M.,University Mayor
Revista Chilena de Pediatria | Year: 2010

This paper presents some critical considerations regarding the growing adoption, by families, of alternative treatments and diets for the treatment of various disorders like autism in children. Research does not seem to support such practices, with the exception of the relationship between timesoral and vaccines, neurological and cardiac disorders. Issues to consider are pointed out in the need to opt for biological treatments, and the need for families and research teams to work together for the purpose of clarifying such procedures.

Beltran S.,University Mayor | Munoz-Bergmann C.A.,University Mayor | Elola-Lopez A.,University Mayor | Quintana J.,University Mayor | And 2 more authors.
Biological Research | Year: 2015

Background: Vibrio parahaemolyticus (V. parahaemolyticus) is a Gram-negative, halophilic bacterium recognized as one of the most important foodborne pathogen. When ingested, V. parahaemolyticus causes a self-limiting illness (Vibriosis), characterized mainly by watery diarrhoea. Treatment is usually oral rehydration and/or antibiotics in complicated cases. Since 1996, the pathogenic and pandemic V. parahaemolyticus O3:K6 serotype has spread worldwide, increasing the reported number of vibriosis cases. Thus, the design of new strategies for pathogen control and illness prevention is necessary. Lactobacillus sp. grouped Gram positive innocuous bacteria, part of normal intestinal microbiota and usually used as oral vaccines for several diarrheic diseases. Recombinants strains of Lactobacillus (RL) expressing pathogen antigens can be used as part of an anti-adhesion strategy where RL block the pathogen union sites in host cells. Thus, we aimed to express MAM-7 V. parahaemolyticus adhesion protein in Lactobacillus sp. to generate an RL that prevents pathogen colonization. Results: We cloned the MAM-7 gene from V. parahaemolyticus RIMD 2210633 in Lactobacillus expression vectors. Recombinant strains (Lactobacillus rhamnosus pSEC-MAM7 and L. rhamnosus pCWA-MAM7) adhered to CaCo-2 cells and competed with the pathogen. However, the L. rhamnosus wild type strain showed the best capacity to inhibit pathogen colonization in vitro. In addition, LDH-assay showed that recombinant strains were cytotoxic compared with the wild type isogenic strain. Conclusions: MAM-7 expression in lactobacilli reduces the intrinsic inhibitory capacity of L. rhamnosus against V. parahaemolyticus. © 2016 Beltran et al.

Discover hidden collaborations