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Background: Since the middle of the last century, North America and occidental countries have reported variations in the frequency of gastrointestinal neoplasms. Several environmental factors, mainly nutritional and dietary exposure, as well as habits have contributed to these changes. We have documented these changes in Mexico during the last 35 years. Aims: To define the epidemiologic changes of gastrointestinal neoplasms during the last three decades in our population. Methods: We summarized the evidence of an observational study, registering the frequency of different gastrointestinal malignancies from four institutions of socioeconomically different populations in Mexico City during 35 years. The Mexican National Academy of Medicine supported this effort. During this period, two nutritional surveys took place, letting us define the relationship between dietary changes and cancer occurrence. Results: Replacement of gastric cancer by colorectal cancer as the leading gastrointestinal malignancy. Relationship between cancer and diet changes. Increase of esophageal adenocarcinoma in relation to epidermoid carcinoma secondary to gastroesophageal reflux and Barrett's esophagus rising incidence. Gall bladder cancer had a high frequency in one institution, probably related to genetic and racial factors. Conclusions: This epidemiologic data should lead us to implement sanitary measures for the prevention, early diagnosis, and appropriate treatment of gastrointestinal neoplasms. Source


Rodriguez-Fuentes N.,National Autonomous University of Mexico | Rodriguez-Hernandez A.G.,National Autonomous University of Mexico | Enriquez-Jimenez J.,Instituto Nacional Of Ciencias Medicas Y Nutricion Salvador Zubiran Incmnsz | Fuentes-Mera L.,Hospital General Dr. Manuel Gea Gonzalez | And 3 more authors.
Biochemical and Biophysical Research Communications | Year: 2013

Bovine bone matrix Nukbone® (NKB) is an osseous tissue-engineering biomaterial that retains its mineral and organic phases and its natural bone topography and has been used as a xenoimplant for bone regeneration in clinics. There are not studies regarding its influence of the NKB in the behavior of cells during the repairing processes. The aim of this research is to demonstrate that NKB has an osteoinductive effect in human mesenchymal stem cells from amniotic membrane (AM-hMSCs). Results indicated that NKB favors the AM-hMSCs adhesion and proliferation up to 7 days in culture as shown by the scanning electron microscopy and proliferation measures using an alamarBlue assay. Furthermore, as demonstrated by reverse transcriptase polymerase chain reaction, it was detected that two gene expression markers of osteoblastic differentiation: the core binding factor and osteocalcin were higher for AM-hMSCs co-cultured with NKB in comparison with cultivated cells in absence of the biomaterial. As the results indicate, NKB possess the capability for inducing successfully the osteoblastic differentiation of AM-hMSC, so that, NKB is an excellent xenoimplant option for repairing bone tissue defects. © 2013 Elsevier Inc. All rights reserved. Source


Fernandez-Torres J.,Instituto Nacional Of Rehabilitacion | Fernandez-Torres J.,National Autonomous University of Mexico | Granados J.,Instituto Nacional Of Ciencias Medicas Y Nutricion Salvador Zubiran Incmnsz | Lopez-Reyes A.,Instituto Nacional Of Rehabilitacion
Human Immunology | Year: 2012

Aplastic anemia (AA) is a hematological disorder characterized by pancytopenia in peripheral blood and hypoplasia in the bone marrow; the majority of cases have no known etiology, but it is thought that genetic and environmental factors can be involved in its pathogenesis. From the genetic viewpoint, it has been reported a significant increase frequency of the human leukocyte antigen HLA-DRB1*15 in patients with AA as compared to ethnically matched healthy controls, this is true in different populations worldwide, which would suggests that this allele participates in the immune regulation of the disease. Objective: To determine gene frequencies of HLA-DRB1 alleles in Mexican mestizo patients with AA. Methods: We analyzed and compared the HLA-DRB1 alleles in 36 Mexican mestizo patients (female gender, n=13; male gender, n=23) with AA to those present in 201 umbilical cord blood (UCB) samples as a control group, this was done by means of the polymerase chain reaction-single specific primer (PCR-SSP) technique. Results: Analysis of gene frequencies of HLA-DRB1* alleles exhibits a significant increase of HLA-DRB1*15 allele in the group of patients with AA as compared to those present in the control group (15.27% vs. 2.23%, respectively; p=1×10-5; odds ratio [OR]=9.3; 95% confidence interval [95% CI]=3.2-27.8). Conclusions: Our results showed a positive association of the DRB1*15 allele in Mexican patients with aplastic anemia, which coincides with that reported internationally. In addition, we think that this allele was introduced to the Mexican population structure inherited from European ancestry. © 2012 American Society for Histocompatibility and Immunogenetics. Source


Carrillo-Garcia A.,National Autonomous University of Mexico | Ponce-de-Leon-Rosales S.,Instituto Nacional Of Ciencias Medicas Y Nutricion Salvador Zubiran Incmnsz | Cantu-de-Leon D.,National Autonomous University of Mexico | Fragoso-Ontiveros V.,National Autonomous University of Mexico | And 4 more authors.
Gynecologic oncology | Year: 2014

The molecular and epidemiologic effect of human papillomavirus (HPV) coinfections in the risk of developing cervical cancer is yet unclear. The aim of this study was to determine the frequency HPV coinfections at different stages of cervical lesions in the development of cervical cancer and the impact of HPV specific type interactions on high-grade squamous intraepithelial lesions (HSIL) and invasive cervical cancer (ICC) risk. HPV testing was performed in 931 cervical samples diagnosed as: negative for intraepithelial lesion or malignancy (NILM); low-grade squamous intraepithelial lesion (LSIL); HSIL; and ICC. For HPV detection and typing two sets of primers from the L1 region were used in the polymerase chain reaction method (PCR) (MY09/MY11/HMB01 and L1C1/L1C2.1/L1C2.2) and HPV type was determined by PCR product sequence. To look for multiple HPV infections, the E6 nested multiplex PCR method was performed in all DNA samples. Odds ratios were calculated as indexes of the strength of the association between the sample category (LSIL/NILM or ICC/HSIL) and the presence of a given viral combination. In HPV positive samples, coinfections are as common in ICC/HSIL as in LSIL/NILM (47.12% and 40.17%, respectively). There is an increased risk to ICC/HSIL when multiple high-risk HPV types are present. The coinfection of HPV68 with HPV16 increases the risk of ICC/HSIL (OR=14.54, P=0.012, after multivariate adjustment), related to the presence of HPV16 or HPV68 alone. These results sustain that specific HPV coinfections confer an increased risk to develop ICC/HSIL. Copyright © 2014 Elsevier Inc. All rights reserved. Source


Antonio-Rincon F.,Instituto Nacional Of Salud Publica | Lopez-Vidal Y.,National Autonomous University of Mexico | Castillo-Rojas G.,National Autonomous University of Mexico | Lazcano-Ponce E.C.,Instituto Nacional Of Salud Publica | And 3 more authors.
Annals of Clinical Microbiology and Antimicrobials | Year: 2011

Background: Helicobacter pylori is associated with chronic gastritis, peptic ulcers, and gastric cancer. Two major virulence factors of H. pylori have been described: the pathogenicity island cag (cag PAI) and the vacuolating cytotoxin gene (vacA). Virtually all strains have a copy of vacA, but its genotype varies. The cag PAI is a region of 32 genes in which the insertion of IS605 elements in its middle region has been associated with partial or total deletions of it that have generated strains with varying virulence. Accordingly, the aim of this work was to determine the cag PAI integrity, vacA genotype and IS605 status in groups of isolates from Mexican patients with non-peptic ulcers (NPU), non-bleeding peptic ulcers (NBPU), and bleeding peptic ulcers (BPU).Methods: The cag PAI integrity was performed by detection of eleven targeted genes along this locus using dot blot hybridization and PCR assays. The vacA allelic, cag PAI genotype 1 and IS605 status were determined by PCR analysis.Results: Groups of 16-17 isolates (n = 50) from two patients with NPU, NBPU, and BPU, respectively, were studied. 90% (45/50) of the isolates harbored a complete cag PAI. Three BPU isolates lacked the cag PAI, and two of the NBPU had an incomplete cag PAI: the first isolate was negative for three of its genes, including deletion of the cagA gene, whereas the second did not have the cagM gene. Most of the strains (76%) had the vacA s1b/m1 genotype; meanwhile the IS605 was not present within the cag PAI of any strain but was detected elsewhere in the genome of 8% (4/50).Conclusion: The patients had highly virulent strains since the most of them possessed a complete cag PAI and had a vacA s1b/m1 genotype. All the isolates presented the cag PAI without any IS605 insertion (genotype 1). Combined vacA genotypes showed that 1 NPU, 2 NBPU, and 1 BPU patients (66.6%) had a mixed infection; coexistence of H. pylori strains with different cag PAI status was observed in 1 NBPU and 2 BPU (50%) of the patients, but only two of these patients (NBPU and BPU) had different vacA genotypes. © 2011 Antonio-Rincón et al; licensee BioMed Central Ltd. Source

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