Maria Manjarrez - Academia.edu (original) (raw)

Papers by Maria Manjarrez

Research paper thumbnail of Dispositivos basicos del aprendizaje: atencion

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Actinomycetoma in Arm Disseminated to Lung with Grains of Nocardia brasiliensis with Peripheral Filaments

Mycopathologia, 2009

Actinomycetomas represent 97.8% of mycetomas in Mexico, where 86.6% are produced by Nocardia bras... more Actinomycetomas represent 97.8% of mycetomas in Mexico, where 86.6% are produced by Nocardia brasiliensis. We report a case of actinomycetoma in the arm by Nocardia brasiliensis disseminated to lung. Uncommon grains were observed which present outside peripheral filaments and also numerous filaments loosing the grains. These characteristics of the grains are due probably because for the long treatment with antibiotics of the patient. In situ antibiotic action against the microcolonies is discussed.

Research paper thumbnail of Parasitic Mycelial Forms of Coccidioides Species in Mexican Patients

Journal of Clinical Microbiology, 2004

Of 26 cases of coccidioidomycosis reported here, 15 showed hyphae, atypical parasitic structures ... more Of 26 cases of coccidioidomycosis reported here, 15 showed hyphae, atypical parasitic structures of Coccidioides spp. in fresh cytologic and/or histologic specimen preparations. The finding of this morphology could have implications which should be considered, especially when the disease affects areas of nonendemicity.

Research paper thumbnail of Molecular characterization of Histoplasma capsulatum isolated from an outbreak in treasure hunters

BMC Infectious Diseases, 2010

Background: In Mexico, primary pulmonary histoplasmosis is the most relevant clinical form of the... more Background: In Mexico, primary pulmonary histoplasmosis is the most relevant clinical form of the disease. The geographical distribution of specific strains of Histoplasma capsulatum circulating in Mexico has not been fully established. Outbreaks must be reported in order to have current, updated information on this disease, identifying new endemic areas, manner of exposure to the fungi, and molecular characterization of the causative agents. We report a recent outbreak of histoplasmosis in treasure hunters and the molecular characterization of two isolates obtained from these patients. Methods: Six patients admitted to the National Institute of Respiratory Diseases (INER) in Mexico City presented severe respiratory symptoms suggestive of histoplasmosis. They acquired the infection in the Veracruz (VZ) endemic zone. Diagnosis was made by X-ray and Computed tomography (CT), liver function, immunological techniques, and culture. Identification of H. capsulatum isolates was confirmed by using Polymerase chain reaction (PCR) was conducted with a probe from the M antigen, and the isolates were characterized by means of Random amplification of polymorphic DNA (RAPD)-PCR employed the 1253 oligonucleotide and a mixture of oligonucleotides 1281 and 1283. These were compared to eight reference strain isolates from neighboring areas.

Research paper thumbnail of An Imported Case of Blastomyces Dermatitidis Infection in Mexico

Mycopathologia, 2003

Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in Nort... more Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in North America (United States of America and Canada),Africa and Asia. We report a case in Mexico, in a three years old childwho had been born in California and lived in Chicago, U.S.A. The patientpresented pulmonary symptoms prior to development of a skin ulcer.Blastomyces dermatitidis was identified by mycological and molecularprocedures. The patient was successfully treated with amphotericin B, oralketoconazole and itraconazole.

Research paper thumbnail of An Imported Case of Blastomyces Dermatitidis Infection in Mexico

Mycopathologia, 2003

Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in Nort... more Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in North America (United States of America and Canada), Africa and Asia. We report a case in Mexico, in a three years old child who had been born in California and lived in Chicago, U.S.A. The patient presented pulmonary symptoms prior to development of a skin ulcer. Blastomyces dermatitidis was identified by mycological and molecular procedures. The patient was successfully treated with amphotericin B, oral ketoconazole and itraconazole.

Research paper thumbnail of Comparative viral frequency in Mexican children under 5 years of age with and without upper respiratory symptoms

Journal of Medical Microbiology, 2003

In Mexico, there is a lack of up-to-date published data that show viruses to be the main cause of... more In Mexico, there is a lack of up-to-date published data that show viruses to be the main cause of acute respiratory infection (ARI). The objective of this study was to estimate the comparative viral frequency between children under the age of 5 years with and without ARI (n ¼ 179 in each group) in a suburban community (Nezahualcó yotl City). A nasopharyngeal sample was collected for viral culture and identification was carried out by indirect immunofluorescence (IIF) using mAbs. There were no sex differences between the two groups. Children under 1 year of age with ARI showed a higher frequency (56 %) of viral infections; this was statistically significant (P , 0·05) when compared with the same age group in ARI-free children (17 %). Respiratory syncytial virus (RSV) was the most prevalent type of virus isolated from both groups (38 vs 18 %). A statistically significantly higher number of subjects with ARI (33/179) than without (12/179) were infected with RSV (P , 0·003). Prevalences of four other viruses studied were similar in the two groups. The highest viral incidence of ARI in children was detected in the winter-spring seasonal period.

Research paper thumbnail of Influence on collagen metabolism of vitreous from eyes with proliferative vitreoretinopathy

Ophthalmology, 1995

Purpose: Proliferative vitreoretinopathy (PVR) is characterized by cell proliferation and membran... more Purpose: Proliferative vitreoretinopathy (PVR) is characterized by cell proliferation and membrane formation on the vitreoretinal cavity of the eye. The membranes are composed of extracellular matrix, mainly collagen type I. To explore the possible mechanisms involved in PVR membrane formation, the authors analyzed the role of vitreous humor on collagen turnover.

Research paper thumbnail of Frequency of viruses associated with acute respiratory infections in children younger than five years of age at a locality of Mexico City

Memorias Do Instituto Oswaldo Cruz, 2006

A locality in the district of Tlalpan, Mexico City, was selected in order to identify the viral a... more A locality in the district of Tlalpan, Mexico City, was selected in order to identify the viral agents in children younger than 5 years of age with acute respiratory infection (ARI). A total of 300 children were randomly selected and were included in this study for a period of 13 months. During this period nasopharyngeal exudates were collected for the isolation of viral agents. Monoclonal fluorescent antibodies were used for viral identification after cell culture. Viral infection was detected in 65% of the specimens. The respiratory syncytial virus (RSV) was the most common virus agent detected. Children required an average of two consultations during the study period. Two high incidence peaks were observed, one during the summer and the other during winter; the most frequent viruses during these seasons were influenza A and RSV, respectively. The largest number of viruses was isolated in the group of children between 1 and 2 years of age and in the group between 4 and 5 years of age. This study demonstrated the presence of ARI and of different viruses in a period of 13 months, as well as the most frequent viruses in children younger than 5 years of age from a community of Mexico City.

Research paper thumbnail of Detection of Human Papillomavirus and Relevant Tumor Suppressors and Oncoproteins in Laryngeal Tumors

Clinical Cancer Research, 2006

Purpose: The mechanism of larynx oncogenesis is complex and controlled by various factors, most o... more Purpose: The mechanism of larynx oncogenesis is complex and controlled by various factors, most of them involved in cell proliferation and apoptosis. In this study, we evaluated the levels of two suppressor proteins (pRb and p53) and two oncogenic proteins (c-Myc and Bcl-2), as well as the apoptotic levels and the presence of human papillomavirus (HPV) in both tumor types. Experimental Design: Low-or high-risk HPV viral DNA was determined by PCR and in situ PCR; the level of cellular proteins was examined by immunohistochemistry; the presence of apoptotic cells was evaluated by in situ cell death detection. Results: Most laryngeal papillomatosis samples contained low-risk HPV determined by both techniques. However, 25% of laryngeal carcinoma samples were positive for HPV employing PCR or in situ PCR. In papillomatosis, pRb and p53 levels were higher than in normal larynxes, whereas laryngeal cancer presented the lowest levels. c-Myc oncogene expression was very low in normal and cancer tissues but highly increased in papillomatosis. Bcl-2 expression was low and showed no significant difference between laryngeal papillomatosis and normal larynxes. By contrast, Bcl-2 was clearly up-regulated in cancer. Normal larynx samples and those from laryngeal papillomatosis exhibited similar relatively high numbers of apoptotic cells, whereas in malignant tumors, these cells were scarce. Conclusion: Our results suggest that HPV is an important risk factor in papillomatosis and in some malignant larynx tumors with a strong participation of cellular genes, specifically involved in proliferation and apoptosis. In benign papillomatosis lesions but not in larynx cancer, high p53 activity might preserve the apoptosis process. In larynx cancer, low p53 levels and high bcl-2 expression may be playing an important role to block apoptosis.

Research paper thumbnail of Dispositivos basicos del aprendizaje: atencion

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection

Memorias Do Instituto Oswaldo Cruz, 2008

Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high ... more Adenoviruses (AdV) are commonly involved in acute respiratory infections (ARI), which cause high morbidity and mortality in children. AdV are grouped in six species (A-F), which are associated with a wide range of diseases. The aim of this study was to identify the AdV species infecting non-hospitalized Mexican children with ARI symptoms, attending to the same school. For that, a PCR/RFLP assay was designed for a region of the hexon gene, which was chosen, based on the bioinformatical analysis of AdV genomes obtained from GenBank. A total of 100 children's nasopharyngeal samples were collected from January to June, 2005, and used for viral isolation in A549 cells and PCR/RFLP analysis. Only 15 samples produced cytopathic effect, and in all of them AdV C was identified. AdV C was also identified in eight additional nasopharyngeal samples which were negative for viral isolation. In summary, this outpatient population showed a rate of AdV infection of 23%, and only AdV C was detected.

Research paper thumbnail of Actinomycetoma in Arm Disseminated to Lung with Grains of Nocardia brasiliensis with Peripheral Filaments

Mycopathologia, 2009

Actinomycetomas represent 97.8% of mycetomas in Mexico, where 86.6% are produced by Nocardia bras... more Actinomycetomas represent 97.8% of mycetomas in Mexico, where 86.6% are produced by Nocardia brasiliensis. We report a case of actinomycetoma in the arm by Nocardia brasiliensis disseminated to lung. Uncommon grains were observed which present outside peripheral filaments and also numerous filaments loosing the grains. These characteristics of the grains are due probably because for the long treatment with antibiotics of the patient. In situ antibiotic action against the microcolonies is discussed.

Research paper thumbnail of Parasitic Mycelial Forms of Coccidioides Species in Mexican Patients

Journal of Clinical Microbiology, 2004

Of 26 cases of coccidioidomycosis reported here, 15 showed hyphae, atypical parasitic structures ... more Of 26 cases of coccidioidomycosis reported here, 15 showed hyphae, atypical parasitic structures of Coccidioides spp. in fresh cytologic and/or histologic specimen preparations. The finding of this morphology could have implications which should be considered, especially when the disease affects areas of nonendemicity.

Research paper thumbnail of Molecular characterization of Histoplasma capsulatum isolated from an outbreak in treasure hunters

BMC Infectious Diseases, 2010

Background: In Mexico, primary pulmonary histoplasmosis is the most relevant clinical form of the... more Background: In Mexico, primary pulmonary histoplasmosis is the most relevant clinical form of the disease. The geographical distribution of specific strains of Histoplasma capsulatum circulating in Mexico has not been fully established. Outbreaks must be reported in order to have current, updated information on this disease, identifying new endemic areas, manner of exposure to the fungi, and molecular characterization of the causative agents. We report a recent outbreak of histoplasmosis in treasure hunters and the molecular characterization of two isolates obtained from these patients. Methods: Six patients admitted to the National Institute of Respiratory Diseases (INER) in Mexico City presented severe respiratory symptoms suggestive of histoplasmosis. They acquired the infection in the Veracruz (VZ) endemic zone. Diagnosis was made by X-ray and Computed tomography (CT), liver function, immunological techniques, and culture. Identification of H. capsulatum isolates was confirmed by using Polymerase chain reaction (PCR) was conducted with a probe from the M antigen, and the isolates were characterized by means of Random amplification of polymorphic DNA (RAPD)-PCR employed the 1253 oligonucleotide and a mixture of oligonucleotides 1281 and 1283. These were compared to eight reference strain isolates from neighboring areas.

Research paper thumbnail of An Imported Case of Blastomyces Dermatitidis Infection in Mexico

Mycopathologia, 2003

Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in Nort... more Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in North America (United States of America and Canada),Africa and Asia. We report a case in Mexico, in a three years old childwho had been born in California and lived in Chicago, U.S.A. The patientpresented pulmonary symptoms prior to development of a skin ulcer.Blastomyces dermatitidis was identified by mycological and molecularprocedures. The patient was successfully treated with amphotericin B, oralketoconazole and itraconazole.

Research paper thumbnail of An Imported Case of Blastomyces Dermatitidis Infection in Mexico

Mycopathologia, 2003

Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in Nort... more Blastomycosis is an acute or chronic primary infection of the respiratory system, endemic in North America (United States of America and Canada), Africa and Asia. We report a case in Mexico, in a three years old child who had been born in California and lived in Chicago, U.S.A. The patient presented pulmonary symptoms prior to development of a skin ulcer. Blastomyces dermatitidis was identified by mycological and molecular procedures. The patient was successfully treated with amphotericin B, oral ketoconazole and itraconazole.

Research paper thumbnail of Comparative viral frequency in Mexican children under 5 years of age with and without upper respiratory symptoms

Journal of Medical Microbiology, 2003

In Mexico, there is a lack of up-to-date published data that show viruses to be the main cause of... more In Mexico, there is a lack of up-to-date published data that show viruses to be the main cause of acute respiratory infection (ARI). The objective of this study was to estimate the comparative viral frequency between children under the age of 5 years with and without ARI (n ¼ 179 in each group) in a suburban community (Nezahualcó yotl City). A nasopharyngeal sample was collected for viral culture and identification was carried out by indirect immunofluorescence (IIF) using mAbs. There were no sex differences between the two groups. Children under 1 year of age with ARI showed a higher frequency (56 %) of viral infections; this was statistically significant (P , 0·05) when compared with the same age group in ARI-free children (17 %). Respiratory syncytial virus (RSV) was the most prevalent type of virus isolated from both groups (38 vs 18 %). A statistically significantly higher number of subjects with ARI (33/179) than without (12/179) were infected with RSV (P , 0·003). Prevalences of four other viruses studied were similar in the two groups. The highest viral incidence of ARI in children was detected in the winter-spring seasonal period.

Research paper thumbnail of Influence on collagen metabolism of vitreous from eyes with proliferative vitreoretinopathy

Ophthalmology, 1995

Purpose: Proliferative vitreoretinopathy (PVR) is characterized by cell proliferation and membran... more Purpose: Proliferative vitreoretinopathy (PVR) is characterized by cell proliferation and membrane formation on the vitreoretinal cavity of the eye. The membranes are composed of extracellular matrix, mainly collagen type I. To explore the possible mechanisms involved in PVR membrane formation, the authors analyzed the role of vitreous humor on collagen turnover.

Research paper thumbnail of Frequency of viruses associated with acute respiratory infections in children younger than five years of age at a locality of Mexico City

Memorias Do Instituto Oswaldo Cruz, 2006

A locality in the district of Tlalpan, Mexico City, was selected in order to identify the viral a... more A locality in the district of Tlalpan, Mexico City, was selected in order to identify the viral agents in children younger than 5 years of age with acute respiratory infection (ARI). A total of 300 children were randomly selected and were included in this study for a period of 13 months. During this period nasopharyngeal exudates were collected for the isolation of viral agents. Monoclonal fluorescent antibodies were used for viral identification after cell culture. Viral infection was detected in 65% of the specimens. The respiratory syncytial virus (RSV) was the most common virus agent detected. Children required an average of two consultations during the study period. Two high incidence peaks were observed, one during the summer and the other during winter; the most frequent viruses during these seasons were influenza A and RSV, respectively. The largest number of viruses was isolated in the group of children between 1 and 2 years of age and in the group between 4 and 5 years of age. This study demonstrated the presence of ARI and of different viruses in a period of 13 months, as well as the most frequent viruses in children younger than 5 years of age from a community of Mexico City.

Research paper thumbnail of Detection of Human Papillomavirus and Relevant Tumor Suppressors and Oncoproteins in Laryngeal Tumors

Clinical Cancer Research, 2006

Purpose: The mechanism of larynx oncogenesis is complex and controlled by various factors, most o... more Purpose: The mechanism of larynx oncogenesis is complex and controlled by various factors, most of them involved in cell proliferation and apoptosis. In this study, we evaluated the levels of two suppressor proteins (pRb and p53) and two oncogenic proteins (c-Myc and Bcl-2), as well as the apoptotic levels and the presence of human papillomavirus (HPV) in both tumor types. Experimental Design: Low-or high-risk HPV viral DNA was determined by PCR and in situ PCR; the level of cellular proteins was examined by immunohistochemistry; the presence of apoptotic cells was evaluated by in situ cell death detection. Results: Most laryngeal papillomatosis samples contained low-risk HPV determined by both techniques. However, 25% of laryngeal carcinoma samples were positive for HPV employing PCR or in situ PCR. In papillomatosis, pRb and p53 levels were higher than in normal larynxes, whereas laryngeal cancer presented the lowest levels. c-Myc oncogene expression was very low in normal and cancer tissues but highly increased in papillomatosis. Bcl-2 expression was low and showed no significant difference between laryngeal papillomatosis and normal larynxes. By contrast, Bcl-2 was clearly up-regulated in cancer. Normal larynx samples and those from laryngeal papillomatosis exhibited similar relatively high numbers of apoptotic cells, whereas in malignant tumors, these cells were scarce. Conclusion: Our results suggest that HPV is an important risk factor in papillomatosis and in some malignant larynx tumors with a strong participation of cellular genes, specifically involved in proliferation and apoptosis. In benign papillomatosis lesions but not in larynx cancer, high p53 activity might preserve the apoptosis process. In larynx cancer, low p53 levels and high bcl-2 expression may be playing an important role to block apoptosis.