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1.
Microbiol Resour Announc ; 13(8): e0123223, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39037311

RESUMO

We sequenced the complete genomes of 16 Helicobacter pylori isolates obtained from patients residing in Nariño, Colombia. These isolates were collected from patients presenting various gastric lesions classified according to the Correa cascade classification. The genomic characterization of these isolates provides valuable insights into the structure, composition, and pathogenicity.

2.
Antibiotics (Basel) ; 13(7)2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39061325

RESUMO

The eradication of Helicobacter pylori is a valid strategy for preventing gastric cancer; however, the therapeutic failure of first-line treatments in Colombia is associated with high resistance to metronidazole and amoxicillin. This study explored alternative antibiotics and analyzed point mutations in resistance genes to furazolidone and rifampicin in order to include them in rescue therapy regimens. A total of 239 complete genomes of Helicobacter pylori Colombian strains were compared to that of the ATCC 26695 strain to identify mutations in the rpoB and porD genes for rifampicin and furazolidinone resistance, respectively. While rifampicin resistance mutations were not found, only 0.84% of the isolates showed the porD gene, suggesting that Helicobacter pylori is sensitive to these antibiotics. A phylogenomic analysis of Helicobacter pylori revealed an independent lineage in Colombia (hspColombia). The absence of point mutations in the rpoB gene, together with the scarce mutations identified in the porD gene of Helicobacter pylori, suggest that the hspColombia isolates are sensitive to rifampicin and furazolidone, which could be key to including these antibiotics in the rescue therapies against Helicobacter pylori.

3.
Rev. Asoc. Colomb. Cien. Biol. (En línea) ; 1(35): 20-31, 20231128. graf, ilus
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1518846

RESUMO

Objetivo: Dilucidar el papel de la coevolución del genoma humano y de Helicobacter pylori en la patogenesis gástrica en población de Nariño-Colombia. Materiales y Métodos: Se aisló Helicobacter pylori de biopsias gástricas obtenidas de 292 pacientes con enfermedad gástrica de Nariño. El diagnóstico histológico se realizó por la clasificación de Sydney. Se incluyeron 252 cepas de H. pylori para el análisis MLST, que las asignó a poblaciones ancestrales (hpAfrica1, hpAfrica2, hpEurope, hpEAsia). Para los análisis evolutivos humanos se utilizó Immunochip y el software ESTRUCTURE para determinar proporciones de ascendencia por comparación con 712 secuencias globales de base MLST de H. pylori (http://pubmlst.org/helicobacter). Resultados: Las cepas de H. pylori en Nariño se derivan de cuatro poblaciones ancestrales: Africa (AA1), Europea (AE1 y AE2) y Asia Oriental (AEA). Los aislamientos contenían fracciones sustanciales de ancestría africana AA1 en la costa, y europea, AE2 en la región montañosa. Debido a que la población de montaña tenía un mínimo de ancestría africana del huésped, nos preguntamos si AA1 aumentaba la gravedad de las lesiones gástricas en los sujetos con baja ancestría africana. Tal escenario podría significar una coadaptación interrumpida: disrupción de la coevolución humano-H. pylori. Cuando consideramos a las 56 personas con menos del 17,6% de ancestria africana, encontramos que todas las personas que portaban H. pylori con >19,8% de ancestría africana AA1, n = 20 tenían lesiones severas. Conclusión: Las relaciones coevolutivas humano-H. pylori son biomarcadores importantes de enfermedad gástrica, y la interrupción de estas relaciones desenlazan lesiones gástricas mas avanzadas en Nariño.


Objective: To elucidate the role of the coevolution of the human genome and Helicobacter pylori in gastric pathogenesis in a population from Nariño-Colombia. Materials and Methods: Helicobacter pylori was isolated from gastric biopsies obtained from 292 patients with Nariño gastric disease. The histological diagnosis was made by the Sydney classification. 252 H. pylori isolates were included for MLST analysis, which assigned them to ancestral populations (hpAfrica1, hpAfrica2, hpEurope, hpEAsia). Immunochip was used for human evolutionary analyses. STRUCTURE software to determine ancestry proportions by comparison with 712 global H. pylori MLST base sequences (http://pubmlst.org/helicobacter). Results: The H. pylori strains in Nariño derive from four ancestral populations: African (AA1), European (AE1 and AE2), and East Asian (AEA). The isolates contained substantial fractions of AA1 African ancestry on the coast, and AE2 European ancestry in the mountains. Because the mountain population had minimal African ancestry of the host, we wondered if AA1 increased the severity of gastric lesions in subjects of low African ancestry. Such a scenario could signify disrupted coadaptation: disruption of human-H. pylori coevolution. When we considered the 56 individuals with less than 17.6% African ancestry, we found that all individuals carrying H. pylori with >19.8% AA1 African ancestry, (n = 20) had severe lesions. Conclusion: Human and H. pylori coevolutionary relationships are important biomarkers of gastric disease, and disruption of these relationships results in more advanced gastric lesions in Nariño-Colombia.


Assuntos
Humanos , Neoplasias Gástricas , Biomarcadores Tumorais , Helicobacter pylori , Medical Subject Headings
4.
Int J Mol Sci ; 24(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37685891

RESUMO

Cancer research has prioritized the study of the tumor microenvironment (TME) as a crucial area of investigation. Understanding the communication between tumor cells and the various cell types within the TME has become a focal point. Bidirectional communication processes between these cells support cellular transformation, as well as the survival, invasion, and metastatic dissemination of tumor cells. Extracellular vesicles are lipid bilayer structures secreted by cells that emerge as important mediators of this cell-to-cell communication. EVs transfer their molecular cargo, including proteins and nucleic acids, and particularly microRNAs, which play critical roles in intercellular communication. Tumor-derived EVs, for example, can promote angiogenesis and enhance endothelial permeability by delivering specific miRNAs. Moreover, adipocytes, a significant component of the breast stroma, exhibit high EV secretory activity, which can then modulate metabolic processes, promoting the growth, proliferation, and migration of tumor cells. Comprehensive studies investigating the involvement of EVs and their miRNA cargo in the TME, as well as their underlying mechanisms driving tumoral capacities, are necessary for a deeper understanding of these complex interactions. Such knowledge holds promise for the development of novel diagnostic and therapeutic strategies in cancer treatment.


Assuntos
MicroRNAs , Microambiente Tumoral , Comunicação Celular , Comunicação , Adipócitos , MicroRNAs/genética
5.
Front Microbiol ; 14: 1198325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37485536

RESUMO

The eradication of Helicobacter pylori (H. pylori) using multiple therapies is used as a prevention strategy. However, its efficacy has been compromised by the emergence of single nucleotide polymorphisms in genes associated with H. pylori's resistance to multiple antibiotics. To estimate antibiotic resistance rates associated with mutations in H. pylori genes in the high-cancer-risk population in Colombia, we included 166 H. pylori whole genome sequences from a cohort of individuals with a high risk of gastric cancer. By using the reference strain ATCC 26695, we identified mutations in specific genes to evaluate resistance rates for different antibiotics: 23S rRNA for clarithromycin, 16S rRNA for tetracycline, pbp1A for amoxicillin, gyrA for levofloxacin, and rdxA for metronidazole. The phylogenomic analysis was conducted using the core genome consisting of 1,594 genes of H. pylori-ATCC 26695. Our findings revealed that the resistance rate of H. pylori to clarithromycin was 3.62%, primarily associated with mutations A2143G and A2142G in the 23S rRNA gene. For tetracycline, the resistance rate was 7.23%, with mutations A926G, A926T, and A928C observed in the 16S rRNA gene. Amoxicillin resistance was found in 25.9% of cases, with observed mutations in the pbp1A gene, including T556S, T593, R649K, R656P, and R656H. In the gyrA gene, mutations N87K, N87I, D91G, D91N, and D91Y were identified, resulting in a resistance rate of 12.04% to levofloxacin. The most common mutations in the rdxA gene associated with metronidazole resistance were a stop codon, and mutations at D59N and D59S, resulting in a resistance rate of 99.3%. The high resistance rate of H. pylori to metronidazole indicated that this drug should be excluded from the eradication therapy. However, the resistance rates for tetracycline and clarithromycin did not exceed the established resistance threshold in Colombia. The increased resistance rate of H. pylori to levofloxacin and amoxicillin may partially explain the observed therapeutic failures in Colombia. The phylogenomic tree showed that the H. pylori isolate belongs to its own lineage (hspColombia). These findings offer valuable insights to enhance the characterization of treatment protocols for the specific H. pylori lineage (hspColombia) at the local level.

6.
Univ. salud ; 25(1): A1-A6, ene.-abr. 2023. graf
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-1424733

RESUMO

Introducción: El riesgo de desarrollar cáncer gástrico varía entre continentes, países y regiones. A pesar de que existe una alta prevalencia de Helicobacter pylori su rol como patógeno o mutualista define el riesgo de cáncer gástrico en las regiones de Colombia. Objetivo: Discutir el rol de Helicobacter pylori en el riesgo de cáncer gástrico en Colombia. Materiales y métodos: Revisión de literatura mediante la búsqueda, en las bases de datos LILACS, SciELO, PubMed. Resultados: La coevolución del humano y de Helicobacter pylori; la virulencia de genes cagA, vacA; el tipo de respuesta inmune inflamatoria a Helicobacter pylori (Th1) o antinflamatoria (Th2) y la susceptibilidad humana a cáncer gástrico (IL1β, IL10), junto a la dieta y factores ambientales explican el papel de Helicobacter pylori como patógeno o mutualista asociado al riesgo de cáncer gástrico en Colombia. Conclusiones: Helicobacter pylori tiene un rol mutualista principalmente en poblaciones de bajo riesgo de cáncer gástrico (costas), no obstante, en poblaciones con alto riesgo de cáncer gástrico (andes), su papel como patógeno amerita la erradicación; única estrategia para mitigar la alta incidencia de este cáncer en Colombia.


Introduction: The risk to develop gastric cancer varies between continents, countries and regions. Although there is a high prevalence of Helicobater pylori, its role as either pathogen or mutualistic bacteria defines the risk of gastric cancer in Colombian regions. Objective: To discuss the role of Helicobacter pylori in the risk of gastric cancer in Colombia. Materials and methods: A literature review based on searching LILACS, SciELO, and PubMed databases. Results: Helicobacter pylori role as either a pathogen or mutualistic microorganism associated with gastric cancer risk in Colombia can be explained by analyzing elements such as: human and Helicobacter pylori coevolution; cagA and vacA gene virulence; inflammatory (Th1) or anti-inflammatory (Th2) responses induced by Helicobacter pylori; human susceptibility to gastric cancer (IL1β, IL10); diet; and environmental factors. Conclusions: Even though Helicobacter pylori has a mutualistic role in populations at low gastric cancer risk (coastal regions), its role as a pathogen in populations at higher risk (Andean regions) justifies its eradication as a key strategy to mitigate the incidence of this cancer in Colombia.


Introdução: O risco de desenvolver câncer gástrico varia entre continentes, países e regiões. Embora haja uma alta prevalência de Helicobacter pylori, seu papel como patógeno ou mutualista define o risco de câncer gástrico nas regiões da Colômbia. Objetivo: Discutir o papel do Helicobacter pylori no risco de câncer gástrico na Colômbia. Materiais e métodos: Revisão da literatura por meio da busca, nas bases de dados LILACS, SciELO e PubMed. Resultados: A coevolução de humanos e Helicobacter pylori; a virulência dos genes cagA, vacA; o tipo de resposta imune inflamatória ao Helicobacter pylori (Th1) ou anti-inflamatório (Th2) e a suscetibilidade humana ao câncer gástrico (IL1β, IL10), juntamente com a dieta e fatores ambientais explicam o papel do Helicobacter pylori como patógeno ou mutualista associado ao risco de câncer gástrico na Colômbia. Conclusões: Helicobacter pylori tem um papel mutualista principalmente em populações de baixo risco de câncer gástrico (litoral), porém, em populações com alto risco de câncer gástrico (andes), seu papel como patógeno justifica a erradicação; única estratégia para mitigar a alta incidência deste câncer na Colômbia.


Assuntos
Humanos , Bactérias , Neoplasias , Neoplasias Gástricas , Carcinógenos , Fatores de Risco , Helicobacter pylori
7.
Acta otorrinolaringol. cir. cabeza cuello ; 40(4): 279-285, 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-692122

RESUMO

Objetivo: Valorar si el uso de la dexmedetomidina es apropiado para realizar nasoendoscopias del sueño bajo sedación. Estudio: Observacional, descriptivo, transversal y prospectivo. Material y métodos: Pacientes con diagnóstico confirmado de apnea del sueño por estudio poligráfico cardiorrespiratorio. A todos los pacientes se les realizó una endoscopia del sueño bajo sedación. Resultados: Un total de diez pacientes (seis masculinos y cuatro femeninos) cumplieron los criterios de inclusión, y su promedio de edad era de 44,9. El 60% presentaron una circunferencia de cuello mayor de 39 centímetros. Un IMC promedio de 32,55 kg/m2. Escala de Epworth máxima de 16 y mínima de tres puntos. IAH máximo de 45 y mínimo de dos por hora. Conclusión: Con el uso de dexmedetomidina se logran periodos del sueño más parecidos al fisiológico. Se pudo realizar el estudio por más de 50 minutos, sin el riesgo de depresión respiratoria habitual que se presenta con los medicamentos sedantes convencionales …


Objective: To evaluate if the use of dexmedetomidine is appropriate for DISE. Study design: Observational, descriptive, cross-sectional and prospective study. Subjects and Methods: Patients with diagnosis of sleep apnea undergoing polysomnography study. All subjects underwent a DISE with dexmedetomidine. Results: A total of 10 patients met inclusion criteria. 6 males and 4 females, with a mean age 44.9. 60% file a neck circumference greater than 15 inches. A mean IBM of 32.55 kg/m2. Epworth scale maxima and minima of 16 and 3 points. AIH maxima of 45 and minima of 2 per hour. Conclusion: With the use of dexmedetomidine sleep periods were obtained more similar to the physiological. May conduct the study for more than 50 minutes without risk of respiratory depression usual with conventional drugs sedation…


Assuntos
Humanos , Apneia , Transtornos Respiratórios , Transtornos Respiratórios/diagnóstico , Transtornos Respiratórios/patologia
8.
Acta otorrinolaringol. cir. cabeza cuello ; 38(3): 357-361, sept. 2010.
Artigo em Espanhol | LILACS | ID: lil-605798

RESUMO

Objetivos: Conocer y comparar la evolución del rendimiento auditivo de los pacientes menores de 2 años (prelinguales) y entre 2 a 5 años (perilinguales) con hipoacusia neurosensorial severa a profunda que fueron intervenidos con la colocación del implante coclear. Materiales y métodos: Estudio descriptivo de pacientes del programa de implante coclear del Hospital Militar Central y el Hospital Universitario Clínica San Rafael. Se incluyeron pacientes prelinguales y perilinguales a los cuales se les realizó seguimiento del rendimiento auditivo con las pruebas de IT-MAIS y otthingham durante 3, 6 y 12 meses posimplante durante los años 2001 a 2008. Resultados: La población blanco fueron 84 pacientes de los cuales 53 pacientes cumplieron con los criterios de inclusión, 13 fueron prelinguales y 40 en proceso de adquisición del lenguaje o perilinguales, las dos pruebas alcanzaron un valor estadísticamente significativo con p menor de 0.05, a favor del grupo de pacientes prelinguales, es decir, que la intervención con el implante coclear en los pacientes prelinguales tiene mejor resultado que en los pacientes perilinguales. Conclusión: los pacientes prelinguales con implante coclear tienen mejor rendimiento auditivo que los pacientes perilinguales al año de seguimiento.


Objectives: To get to know and compare the evolution of auditory performance of children younger tan 2 years old (prelingual) and children between two and five years old (perilingual) with severe to profound sensorineural hearing loss that were implanted with a cochlear implant. Material and Methods: A descriptive study of patients that are part of the cochlear implant program at Hospital Militar central and at Hospital Universitario Clínica San Rafael. Prelingual and perilingual patients were included for follow - up of the auditory performance with the following tests IT-MAIS and Nottingham for 3, 6 and 12 months after the implant from 2001 to 2008. Results: The target population was 84 patients out of which 53 patients complied with the inclusion criteria, 13 of which were prelingual and 40 were in the process of acquiring the language or perilingual. Both tests reached a statistically significant value with p lower than 0.05, in favor of the prelingual group of patients. That is, the surgery with a cochlear implant has a better result in prelingual patients than it does in perilingual patients. Conclusion: perilingual patients with cochlear implants have a better auditory performance than perilingual patients after a follow-up of a year.


Assuntos
Perda Auditiva Neurossensorial/cirurgia , Perda Auditiva Neurossensorial/história , Perda Auditiva Neurossensorial/patologia , Perda Auditiva Neurossensorial/terapia
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