Saray Aranda-Romo

Severe pneumonia associated with pandemic (H1N1) 2009 outbreak, San Luis Potosí, Mexico.

Severe pneumonia developed in young adults who had no identifiable risk factors.

Killer-cell immunoglobulin-like receptors (KIR) in severe A (H1N1) 2009 influenza infections

Introduction of a novel influenza virus into the human population leads to the occurrence of pandemic events, such as the one caused by pandemic influenza A (H1N1) 2009 virus. The severity of infections caused by this virus in young adults was greater than that observed in patients with seasonal influenza. Fatal cases have been associated with an abnormal innate, proinflammatory immune response. A critical role for natural killer cells during the initial responses to influenza infections has been suggested. In this study, we assessed the association of killer-cell immunoglobulin-like receptors (KIRs) with disease severity by comparing KIR gene content in patients with mild and severe pandemic influenza virus infections to a control group. We found that activator (KIR3DS1 and KIR2DS5) and inhibitory (KIR2DL5) genes, encoded in group B haplotypes containing the cB01, cB03 and tB01 motifs, are associated with severe pandemic influenza A (H1N1) 2009 infections. Better understanding of how genetic variability contributes to influenza virus pathogenesis may help to the development of immune intervention strategies aiming at controlling the severity of disease.

NKG2C gene deletion in the Mexican population and lack of association to respiratory viral infections

Expansion of a natural killer (NK) cell population that expresses NKG2C has been associated with cytomegalovirus and other viral infections. It has been suggested that this cell population may play a role in infection control. Deletion of the NKG2C gene (homozygous or heterozygous) has been reported with high prevalence in European and Asian populations. However, the effect of NKG2C genotype on NK cell responses to infection remains poorly defined. We determined the prevalence of the NKG2C deletion in a Mexican population (n = 300) and in a group of patients (n = 131) to assess whether NKG2C genotype affects the incidence of symptomatic viral infections caused by influenza or respiratory syncytial virus. The frequency of the NKG2C deletion haplotype in Mexican mestizos was significantly lower (10.3%) than that reported in other populations (17.5–21.9%). No difference in the prevalence of NKG2C deletion was observed in subjects with viral infections compared with the reference population. In addition, no differences in clinical characteristics and infection outcome were observed between patients with and without the NKG2C gene deletion. Our results indicate that copy number variation in the NKG2C gene has no impact on the severity of respiratory viral infections.

Effect of an immunization program on seasonal influenza hospitalizations in Mexican children

We analyzed 2378 respiratory samples of children <5 years of age admitted during a 7-year period in order to determine the contribution of seasonal influenza as a cause of hospitalizations, as well as the impact of the inclusion of influenza vaccine in the childhood immunization program. The presence of influenza virus was demonstrated in 106 (4.4%) samples. The proportion of influenza hospitalizations after the introduction of influenza vaccination was lower (3.4%) than before the establishment of this vaccination program (7.5%; P=0.00002). Our study shows that influenza vaccination programs in children significantly reduce the impact of influenza related hospitalizations.

Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico

Please cite this paper as: Comas‐García et al. (2011) Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico. Influenza and Other Respiratory Viruses 5(2), 76–82.

Oral Candida isolates and fluconazole susceptibility patterns in older Mexican women

OBJECTIVES To assess the epidemiologic and microbiologic profile and in vitro fluconazole susceptibility of yeasts isolated from the oral mucosa colonization/infection of elderly patients. BACKGROUND It has been reported that in older adults increases the oral colonization by Candida particularly C. non-albicans, showing a decreased response to fluconazole, which increases the risk of recalcitrant local and disseminated candidiasis. MATERIALS AND METHODS This was a prospective cross-sectional study conducted in 120 elderly patients. Oral samples were obtained of mucosal Candida colonization or infection by swabbing. Each sample was plated on CHROMagar(®)Candida and incubated (36±1.5°C) for two days. The yeast species were identified using the API(®)ID32-C-AUX. Fluconazole susceptibility was tested using a broth microdilution assay according to the CLSI methods. RESULTS The yeast colonization/infection frequency in the total population was 65.8%. The frequency of the highest Candida carriers was 67.4% in the 70-79-year-old-group. Oral candidiasis was present in 20%, with a tendency to increase with age (33.3% of adults aged>80years), it was determined that the use of prosthesis is associated with a higher colonization rate (Chi2, p=0.011). The frequency of colonization/infection cases with more than one species showed a tendency to increase with age; 18.9% in the 60-69 year-old-group, 20.9% in the 70-79-year-old-group and 29.2% in the ≥80 year-old-group. About fluconazole susceptibility: for C. albicans, 20.3%, about Candida non-albicans species 15.3% were dose dependently susceptible (DDS) and 17.9% were resistant. CONCLUSIONS After 80 years of age, there is a considerable increase in Candida non-albicans species and a reduced susceptibility to fluconazole.

Susceptibilidad in vitro de Candida albicans y no albicans Aisladas de Prótesis Dentales de Pacientes con Estomatitis Protésica a Tres Sustancias de Desinfección

A pesar del gran numero de productos disponibles para la limpieza de protesis dentales, el 60% de los portadores hace uso de ellos, posiblemente por la situacion economica. El objetivo fue determinar la susceptibilidad antifungica in vitro que presenta Candida y sus especies a tres sustancias utilizadas para la desinfeccion de protesis (hipoclorito de sodio, acido acetico y solucion de superoxidacion). Se obtuvieron aislados clinicos de Candida de pacientes portadores de protesis diagnosticados con estomatitis protesica, para su posterior estudio de susceptibilidad in vitro a las diferentes sustancias. El hipoclorito de sodio al 0,5% mostro in vitro una mayor inhibicion para las cepas de Candida albicans y Candida no albicans. El acido acetico y la solucion de superoxidacion no mostraron inhibicion in vitro frente a ambas cepas. El hipoclorito de sodio al 0,5% tiene un efecto inhibitorio in vitro sobre las cepas de C. albicans y Candida no albicans.

Tau Protein in Oral Mucosa and Cognitive State: A Cross-sectional Study

Neurodegenerative diseases are characterized by the presence of abnormal aggregates of proteins in brain tissue. Among them, the presence of aggregates of phosphorylated Tau protein (p-Tau) is the hallmark of Alzheimer’s disease (AD) and other major neurodegenerative disorders such as corticobasal degeneration and frontotemporal dementia among others. Although Tau protein has previously been assumed to be exclusive to the central nervous system, it is also found in peripheral tissues. The purpose of this study was to determine whether there is a differential Tau expression in oral mucosa cells according to cognitive impairment. Eighty-one subjects were enrolled in the study and classified per Mini-Mental State Examination test score into control, mild cognitive impairment (MCI), and severe cognitive impairment (SCI) groups. Immunocytochemistry and immunofluorescence revealed the presence of Tau and four p-Tau forms in the cytoplasm and nucleus of oral mucosa cells. More positivity was present in subjects with cognitive impairment than in control subjects, both in the nucleus and cytoplasm, in a speckle pattern. The mRNA expression of Tau by quantitative real-time polymerase chain reaction was higher in SCI as compared with the control group (P < 0.01). A significantly higher percentage of immunopositive cells in the SCI group was found via flow cytometry in comparison to controls and the MCI group (P < 0.01). These findings demonstrate the higher presence of p-Tau and Tau transcript in the oral mucosa of cognitively impaired subjects when compared with healthy subjects. The feasibility of p-Tau quantification by flow cytometry supports the prospective analysis of oral mucosa as a support tool for screening of proteinopathies in cognitively impaired patients.