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Search Results: 1 - 10 of 97365 matches for " José Antonio Rivera-Tapia "
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Micoplasmas y antibióticos
Rivera-Tapia José Antonio,Rodríguez-Preval Nadia
Salud Pública de México , 2006,
Mycoplasmas detection in cells cultures
Rivera-Tapia José Antonio,Castillo-Viveros Linda Valeria,Sánchez-Hernández José Antonio
Revista Ciencias Biomédicas , 2010,
Abstract: INTRODUCTION. Cells cultures are widely used in both biomedical and biotechnological research centers and industry, as well as for diagnostic test in hospitals. Contaminations of cells cultures with microbial organisms as well as with virus or other eukaryotic cell lines are a major problem in cell culture related research.OBJECTIVE. Mycoplasmas detection in cells cultures came from biomedical laboratories.MATERIAL AND METHODS. The cells cultures screened for mycoplasmas by using of microbiological culture and PCR. Cells cultures were grown in the absence of antibiotics for 3-4 days. The identified based on alterations in the pH of the broth in the absence of turbidity, production of fried egg colonies. Comparison between microbiological and PCR were made using Student T test.RESULTS. Mycoplasmas were detected by culture in 9/20 (45%) of the cell culture samples and PCR revealed the presence of target DNA in 10/20 (50%) samples. Mycoplasmas detection between the microbiological culture and PCR showing not significant differences (P>0.05).CONCLUSION. Mycoplasmas detection in cell cultures must be strengthen with another technique to validate the results.RESUMENINTRODUCCIóN. Los cultivos celulares se utilizan frecuentemente en la investigación biomédica, en el área industrial y en pruebas diagnósticas en los hospitales. La contaminación de los cultivos celulares por microorganismos o por contaminación cruzada entre cultivos es uno de los principales problemas en la investigación.OBJETIVO. Detección de micoplasmas en cultivos celulares provenientes de diferentes laboratorios biomédicos.MATERIAL Y METODOS. Los cultivos celulares se evaluaron para detectar presencia de micoplasmas por medio de cultivo microbiológico y PCR. Los cultivos celulares fueron crecidos en ausencia de antibióticos durante 3-4 días. La identificación se presentó por el cambio en el indicador de pH y ausencia de turbidez en el caldo y por la presencia en agar de las colonias características a través de microscopia estereoscópica. La comparación de los resultados obtenidos entre el método microbiológico y PCR se realizó con la prueba de T de Student.RESULTADOS. Por el método microbiológico se detectó en 9/20 muestras (45%) presencia de micoplasmas en los cultivos celulares y por medio de la prueba de PCR resultaron positivas 10/20 muestras (50%) de cultivos celulares. El análisis estadístico mostró que no hay diferencia significativa (P>0.05) en la detección entre el método microbiológico y PCR.CONCLUSIONES. Es recomendable que la detección de micoplasmas en cultivos celulares debe refo
Cytologic smear study in patients with and without monopause
Sánchez-Hernández José Antonio,Rebollo-Ramírez María Fernanda,Paulin-Badillo José Antonio,Rivera-Tapia José Antonio
Revista Ciencias Biomédicas , 2011,
Abstract: Introduction: The onset of menopause is given by the gradual decrease of estrogenlevels, eventually leading to the absence of menstruation, causing a major change inthe conditions governing the cervicovaginal environment. Some studies have reporteda high frequency of cervicovaginal infections in menopausal women.Objective: To identify cervical vaginal infectious diseases that occur in patients whohave gone through menopause and those who have not.Material and Methods: We analyzed the results of the interrogation and the cellularfootage from the cervical-vaginal canal of all patients attending the Laboratorio deBiología Celular de la Facultad de Medicina de la Benemérita Universidad Autónoma dePuebla, México (BUAP) the program on Early Detection of Cancer (DOC) or Pap smearsfrom 2001 to 2008. We analyzed the results of 196 postmenopausal women (group M)and 836 menopausal patients (group NM).Results: Based on the classification of Bethesda 2001, the M group, 29 cases (14.8%)were negative for malignancy, 167 cases (85.2%) reactive changes, there were no casesof Atypical Squamous Cells of Undetermined Significance ASCUS (for short English),squamous intraepithelial lesion of low grade (LSIL) squamous intraepithelial (HSIL),squamous cell carcinoma. NM group, 112 cases (13.4%) were negative for malignancy,704 cases (84.2%) with reactive changes, 0 cases (0.0%) ASCUS, 18 cases (2.2%)with LSIL, 2 cases (0.2%) with HSIL not found patients with squamous cell carcinoma(Figure 1). As cells aggregate, Leukocyte: group M. 153 cases (78.06%), NM group.730 cases (87.32%); Erythrocytes: M group 69 cases (35.2%), NM group 306 cases(36.60%). Mixed flora, viral Reaction: 0 (0%) M, 2 (0.24%) NM; T. vaginalis 13 (6.63%9 M, 52 (6.22%) NM, bacterial vaginosis: 109 (55.61%) M, 540 (64.59%) NM, Fungi:72 (36.73%) M, 232 (27.75%) NM; Parasites : 0 (0.00%) M, 0 (0.00%) NM; Cytolysis:13 (6.63%) M, 63 (7.54%) NM; Lactobacillus: 25 (12.76%) M, 205 (24.52%) NM.Conclusions: A high percentage of postmenopausal women and postmenopausalwomen not occur with cervicovaginal inflammation, the presence of lactobacilli is lowerin postmenopausal patients, encouraging fungal infections, an important frequency inmenopausal women with bacterial vaginosis, the menopause is not a factor risk forthe prevalence of infections with T. vaginalis viruses.RESUMEN:Introducción: la aparición de la menopausia está dada por la disminución paulatinade los niveles de estrógeno que llevan finalmente a la ausencia de la menstruación,generando un gran cambio en las condiciones que rigen el entorno cervicovaginal.Alguno
Incidencia de Candida albicans en pacientes estudiadas en la Ciudad de Puebla, México
José Antonio Sánchez-Hernández, José Antonio Rivera-Tapia, Laura Lizeth Coyotécatl-García, Emmanuel Mendoza-López
Acta Cientifica Estudiantil , 2009,
Animal model of Mycoplasma fermentans respiratory infection
Antonio Yá?ez, Azucena Martínez-Ramos, Teresa Calixto, Francisco Javier González-Matus, José Antonio Rivera-Tapia, Silvia Giono, Constantino Gil, Lilia Cedillo
BMC Research Notes , 2013, DOI: 10.1186/1756-0500-6-9
Abstract: Mycoplasmas were detected by culture and PCR. The three mycoplasma strains induced an interstitial pneumonia; they also migrated to several organs and persisted there for at least 50 days. Mycoplasma fermentans P 140 induced a more severe damage in lungs than Mycoplasma fermentans PG 18. Mycoplasma pneumoniae produced severe damage in lungs and renal damage.Mycoplasma fermentans induced a respiratory tract infection and persisted in different organs for several weeks in hamsters. This finding may help to explain the ability of Mycoplasma fermentans to induce pneumonia and chronic infectious diseases in humans.Mycoplasma fermentans was first isolated from the lower genitourinary tract of humans in the early 1950’s. Reports in the 1970’s of Mycoplasma fermentans in joints of patients suffering rheumatoid arthritis (RA) raised expectations for its role as pathogen [1,2]. When AIDS appeared, interest about mycoplasmas increased, species of the Class Mollicutes Mycoplasma fermentans, Mycoplasma pirum and Mycoplasma penetrans were isolated from AIDS patients. Several researches thought that mycoplasmas may act as cofactors in HIV associated disease progression [3].The role of mycoplasmas in RA is controversial. Early work suggesting a link between Mycoplasma fermentans and human RA was unconvincing because it was isolated in a small proportion of patients, the bacteria was rarely isolated from the genitourinary tract and there was no evidence that it could colonize other sites [2]. The advent of polymerase chain reaction (PCR) provided new insights. Thus by the use of PCR, Mycoplasma fermentans has been found in the throat, peripheral blood leucocytes and urine of HIV positive and HIV negative patients [4]. More evidence has accumulated recently to establish an important and emerging role for Mycoplasma fermentans as pathogen in human respiratory tract and rheumatic diseases [1,2].Presence of Mycoplasma fermentans in throat of humans let us think about the possibility tha
Antimicrobial multiresistance of enterotoxigenic and enteropathogenic escherichia Coli detected in clinical specimens by polymerase chain reaction
Chávez-Bravo Edith,Rivera-Tapia José Antonio,Casta?eda-Roldán Elsa Iracena,Gil-Juárez Constantino
Revista Ciencias Biomédicas , 2012,
Abstract: Introduction: Increasing antimicrobial resistance of enteric pathogens has attractedattention mainly in developing countries where the prevalence of acute diarrheal diseasecontinues to be major cause of mortality and morbidity. Diarrheagenic pathotypes of E.coli, enterotoxigenic (ETEC) and enteropathogenic (EPEC) are associated with this disease.Objective: To determine antimicrobial susceptibility of enterotoxigenic and enteropathogenicEscherichia coli in clinical samples from patients with diarrhea.Material and methods: Fifty eight strains of E. coli isolated from children under five years,and forty five from adults were analyzed by PCR; we used disk diffusion method to evaluateantimicrobial susceptibility to 12 antibiotics in both, typified pathotypes and strains of E.coli without any of the tested genes (E. coli SNG).Results: Enteropathogenic Escherichia coli was found in 41% of samples andenterotoxigenic Escherichia coli in 37%; the former predominating in strains isolatedfrom adults (42%) and the last in strains isolated from infants (43%). The most commonresistance markers were carbenicillin (83%), ampicillin (70%) and trimethoprimsulfamethoxazole(49%). We found a high percentage of strains (87%) resistant to at leastone antibiotic and multiresistance of three to six antibiotics was found in 62%.In strains isolated from children, multiresistance was found in 63% and 52% for EPEC andETEC, and strains isolated from adults 53% and 71% respectively.Conclusion: Strains of E. coli showed similar resistance profiles, predominatingmultiresistance in EPEC, ETEC and E. coli SNG (four antibiotics), reflecting frequent exposureof enteropathogens to antibiotics, so increasing resistance reduce effectiveness of availableantimicrobials.RESUMEN:Introducción: la creciente resistencia antimicrobiana de patógenos entéricos hallamado la atención principalmente en países en vías de desarrollo, donde la prevalenciade enfermedades diarreicas agudas sigue causando grandes índices de mortalidad ymorbilidad. Los patotipos diarrogénicos de E.coli: EPEC y ETEC se encuentran asociadosa este tipo de enfermedades.Objetivo: determinar la susceptibilidad antimicrobiana de los patogrupos EPEC y ETECen muestras clínicas de pacientes con cuadro diarreico.Material y métodos: mediante la técnica de PCR se caracterizaron 58 cepas de E.coliaisladas de ni os menores a cinco a os y en 45 cepas de adultos, se utilizó la técnicade difusión en disco para evaluar la susceptibilidad antimicrobiana a doce antibióticostanto en los patotipos tipificados como en las cepas E.coli sin ninguno de los
Diagnóstico de Mycoplasma genitalium por amplificación de los genes MgPa y ARN ribosomal 16S
Fernández-Molina,Carmen; Rodríguez-Preval,Nadia; Rodríguez-González,Islay; Agnese-Latino,María; Rivera-Tapia,José Antonio; Ayala-Rodríguez,Idalia;
Salud Pública de México , 2008, DOI: 10.1590/S0036-36342008000500007
Abstract: objective: mycoplasma genitalium has been associated with nongonococcal urethritis (ngu). diagnosis by pcr has become the primary detection method for this organism. thus, diagnosis by dna amplification using the pcr technique should be utilized. material and methods: gmf/gmr and mgpf/mgpr primer pairs, complementary to the m. genitalium 16s rrna and mgpa genes, respectively, were selected. specificity and sensibility assays were conducted and clinical samples were studied. results: the pcr with each primer pair was specific only for m. genitalium, and the sensibility was higher with the gmf/gmr primers. in the study of 34 clinical samples, 18,5% were positive for m. genitalium, with more positive samples when the mgpf/mgpr primers were used. conclusions: dna amplification by pcr should be applied in clinical practice to the diagnosis of m. genitalium in patients with ngu should using.
Emisión de ceniza volcánica y sus efectos
A. Rivera-Tapia,A. Ya?ez-Santos,L. Cedillo-Ramírez
Ecosistemas , 2005,
Abstract: La actividad volcánica es una fuente natural de contaminación, la cual aporta una cantidad considerable de contaminantes, principalmente a la atmósfera. Se ha documentado que dicha actividad representa riesgos para los ecosistemas y las poblaciones humanas que se ubican cerca de los edificios volcánicos, no obstante se ha descrito que incluso organismos que se localizan a distancias considerables de las zonas con actividad volcánica también pueden verse afectados. Dentro de los principales riesgos volcánicos destacan la emisión de ceniza y gases, relacionándose con la cantidad y el número de exposiciones a dichos eventos. En este contexto, la colaboración entre vulcanólogos, meteorólogos, químicos, biólogos, agrónomos y profesionales de la salud permitirá mitigar los riesgos de la actividad volcánica. El objetivo de esta revisión es presentar los riesgos para el medio ambiente y la salud asociados con la emisión de ceniza volcánica.
A Clifford Bundle Approach to the Wave Equation of a Spin 1/2 Fermion in the de Sitter Manifold
W. A. Rodrigues Jr.,S. A. Wainer,M. Rivera-Tapia,E. A. Notte-Cuello,I. Kondrashuk
Physics , 2015,
Abstract: In this paper we give a Clifford bundle motivated approach to the wave equation of a free spin $1/2$ fermion in the de Sitter manifold, a brane with topology $M=\mathrm{S0}(4,1)/\mathrm{S0}(3,1)$ living in the bulk spacetime $\mathbb{R}^{4,1}=(\mathring{M}=\mathbb{R}^{5},\boldsymbol{\mathring{g}})$ and equipped with a metric field $\boldsymbol{g:=-i}^{\ast}\boldsymbol{\mathring{g}%}$ with $\boldsymbol{i}:M\rightarrow\mathring{M}$ being the inclusion map. To obtain the analog of Dirac equation in Minkowski spacetime in the structure $\mathring{M}$ we appropriately factorize the two Casimir invariants $C_{1}$ and $C_{2}$ of the Lie algebra of the de Sitter group using the constraint given in the linearization of $C_{2}$ as input to linearize $C_{1}$. In this way we obtain an equation that we called \textbf{DHESS1,}which in previous studies by other authors was simply postulated.$.$Next we derive a wave equation (called \textbf{DHESS2}) for a free spin $1/2$ fermion in the de Sitter manifold using a heuristic argument which is an obvious generalization of a heuristic argument (described in detail in Appendix D) permitting a derivation of the Dirac equation in Minkowski spacetime and which shows that such famous equation express nothing more than the fact that the momentum of a free particle is a constant vector field over timelike \ integral curves of a given velocity field. It is a remarkable fact that \textbf{DHESS1}and \textbf{DHESS2}\ coincide. One of the main ingredients in our paper is the use of the concept of Dirac-Hestenes spinor fields. Appendices B and C recall this concept and its relation with covariant Dirac spinor fields usualy used by physicists.
Monitoreo bacteriológico en el aire interior de un edificio
Rivera Tapia José Antonio, Sánchez Hernández José Antonio, Ortiz Segura Gerardo, Barahona Argueta Carlos.
Acta Cientifica Estudiantil , 2009,
Abstract: El estudio de la calidad del aire en interiores es un problema ambiental, de tal forma se ha planteado que la contaminación en interiores implica efectos negativos en la salud. La presencia de agentes biológicos en el aire de interiores, puede contribuir al síndrome del edificio enfermo, condicionando padecimientos en vías respiratorias, tracto digestivo, ojos y en la piel de los ocupantes. El objetivo del presente trabajo fue monitorear la presencia de bacterias en el aire interior en un edificio universitario de tecnología educativa. Para el muestreo por placa expuesta se emplearon medios enriquecidos y selectivos, y para la identificación de los aislamientos se utilizó medio de orientación. El muestreo se realizó por triplicado en diferentes áreas del edificio a una altura de 1.50 metros durante 30 minutos. El muestreo se realizó durante tres meses a las 12:00 horas, los medios de cultivo se incubaron a 37 oC durante 48 horas. Durante los tres meses de muestreo se aislaron un total de 4383 UFC, distribuyéndose en los géneros Proteus (30.5%), Escherichia (11%) y Enterococcus (58.5%). Los datos obtenidos impactan desde el punto de vista social, laboral y de salud pública, ya que se monitoreo la presencia de bacterias en un ambiente intramuros. Y aunque las bacterias asiladas se consideran inocuas, no se debe descartar que otro factor biótico o abiótico puede condicionar su papel como agentes etiológicos en algunos padecimientos propios del humano.
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