Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 82
Filtrar
1.
Med Oral Patol Oral Cir Bucal ; 29(2): e273-e279, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37992142

RESUMEN

BACKGROUND: The differentiation between primary and metastatic salivary gland neoplasms (SGNs) helps in determining appropriate management strategies, including the need for additional diagnostic tests, surveillance, or aggressive treatment. The purpose of this study was to identify and quantify the immature and mature dendritic cells (DCs) in metastatic and no metastatic SGNs and determine its association with clinicopathological findings. MATERIAL AND METHODS: Cross-sectional, observational, and descriptive study that includes 33 malignant salivary gland neoplasms [MSGN (6, 18.1% metastatic)], and 22 pleomorphic adenomas (PA), as a control group. Clinical and histopathological characteristics were obtained. Immunohistochemistry for human leukocyte antigen D-related (HLA-DR), CD1a, CD83, and Ki-67 proteins was done. Positive intra- and peritumoral DCs were counted. RESULTS: Individuals with MSGN had a lower density of intratumoral HLA-DR+ cells than those with PA (p=0.001), Ki-67 immunostaining was significantly higher in MSGN than in PA (6% vs. 1.4%, p<0.001). Metastatic MSGN showed less intratumoral CD1a+ than non-metastatic (3.2 vs. 165.1, p=0.001). No differences in intra- and peritumoral CD83+ cells were found between benign and malignant SGN. CONCLUSIONS: These results suggest that the immune-protective function of intratumoral DCs is compromised in MSGNs. DCs markers may represent useful prediction tools for metastases in salivary gland malignancies, with crucial implications in the implementation of appropriate disease management strategies.


Asunto(s)
Adenoma Pleomórfico , Neoplasias de las Glándulas Salivales , Humanos , Estudios Transversales , Antígeno Ki-67 , Células Dendríticas , Antígenos HLA-DR
2.
J Immunol Res ; 2022: 1810804, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35465350

RESUMEN

Methods: We analyzed the secretion of cytokines, chemokines, and growth factors in 22Rv1, LNCaP, and DU145 cells. In these cells, we also evaluated the expression of NK ligands, IL6R, STAT-3, and phosporylated STAT-3. In NK-92 cells, we evaluated the effects of Stattic (Stt) and tocilizumab (Tcz) on NK receptors. In addition, we assessed if the disruption of the IL6R/STAT-3 pathway and blockade of TIGIT potentiated the cytotoxicity of NK-92 cells versus DU145 cells. Results: DU145 abundantly secretes M-CSF, VEGF, IL-6, CXCL8, and TGF-ß. Furthermore, the expression of CD155 was found to increase in accordance with aggressiveness and metastatic status in the prostate cancer cells. Stt and Tcz induce a decrease in STAT-3 phosphorylation in the DU145 cells and, in turn, induce an increase of NKp46 and a decrease of TIGIT expression in NK-92 cells. Finally, the disruption of the IL6R/STAT-3 axis in prostate cancer cells and the blocking of TIGIT on NK-92 were observed to increase the cytotoxicity of NK-92 cells against DU145 cells through an increase in sFasL, granzyme A, granzyme B, and granulysin. Conclusions: Our results reveal that the combined use of inhibitors directed against the IL6R/STAT-3 axis and TIGIT enhances the functional activity of NK cells against castration-resistant prostate cancer cells.


Asunto(s)
Células Asesinas Naturales , Neoplasias de la Próstata , Humanos , Células Asesinas Naturales/metabolismo , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Receptores Inmunológicos/metabolismo , Receptores de Interleucina-6
4.
Hernia ; 26(2): 467-472, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34767104

RESUMEN

PURPOSE: The closure of a stoma is frequently associated with an acceptable morbidity and mortality. One of the most frequent complications is incisional hernia at the stoma site, which occurs in 20%-40% of cases, higher than incisions in other parts of the abdomen. The objective of this study was to identify the risk factors associated with the presentation of incisional hernia after stoma closure, this in order to select patients who are candidates for prophylactic mesh placement during closure. METHODS: An unpaired case-control study was conducted. This study involved 164 patients who underwent a stoma closure between January 2014 and December 2019. Associated factors for the development of incisional hernia at the site of the stoma after closure were identified, for which it was performed a logistic regression analysis. RESULTS: 41 cases and 123 controls were analyzed, with a mean follow-up of 35.21 ± 18.42 months, the mean age for performing the stoma closure was 65.28 ± 14.07 years, the most frequent cause for performing the stoma was malignant disease (65.85%). Risk factor for the development of incisional hernia at the stoma site after its closure was identified as a history of parastomal hernia (OR 5.90, CI95% 1.97-17.68). CONCLUSIONS: The use of prophylactic mesh at stoma closure should be considered in patients with a history of parastomal hernia since these patients present a significantly higher risk of developing a hernia.


Asunto(s)
Hernia Incisional , Estomas Quirúrgicos , Anciano , Estudios de Casos y Controles , Hernia/etiología , Herniorrafia , Humanos , Hernia Incisional/etiología , Hernia Incisional/prevención & control , Persona de Mediana Edad , Mallas Quirúrgicas/efectos adversos , Estomas Quirúrgicos/efectos adversos
5.
Int Immunopharmacol ; 93: 107341, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33486334

RESUMEN

Although acute stress generally exerts positive effects on the immune system, chronic stress typically causes immunosuppression via the hypothalamic-pituitary-adrenal (HPA) axis. In this study, the effects of capsaicin (1.28 mg/kg intraperitoneally [i.p.] for 7 days) on immune parameters were evaluated under conditions of chronic stress. Capsaicin treatment significantly increased the immune response as evaluated by the delayed-type hypersensitivity (DTH) reaction to dinitrofluorobenzene (DNFB) and splenocyte proliferation assays- It also is able to rescue the splenocytes of the apoptosis induced by stress. The capsaicin treatment increased the production of Th1 cytokines and decreased the production of Th2 cytokines and TGF-ß1 in the plasma and culture supernatants of immunosuppressed mice, which is associated with the modulation of Th2 induced by stress cells. Moreover, the production of corticosterone significantly decreased in capsaicin-treated animals as compared to control groups. The capsaicin treatment further attenuated the immunosuppression induced by the corticosterone treatment (40 mg/kg i.p. for 7 days), albeit less potently, as exhibited in the DTH response. Intriguingly, the capsaicin treatment decreased the induction of IL-10, IL-4, and TGF-ß1 through high doses of corticosterone, indicating direct cellular immunomodulation. These results show, that capsaicin is able to modulate chronic stress-induced immunosuppression, mediating corticosterone released inhibition, but also, that capsaicin significantly modulates the pharmacological action of corticosterone in vivo.


Asunto(s)
Capsaicina/farmacología , Tolerancia Inmunológica/efectos de los fármacos , Factores Inmunológicos/farmacología , Estrés Fisiológico/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Corticosterona/farmacología , Citocinas/sangre , Citocinas/inmunología , Dinitrofluorobenceno , Hipersensibilidad Tardía/inmunología , Masculino , Ratones Endogámicos BALB C , Bazo/citología , Estrés Fisiológico/inmunología , Factor de Crecimiento Transformador beta1/sangre , Factor de Crecimiento Transformador beta1/inmunología
6.
Immunol Lett ; 196: 140-148, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29481824

RESUMEN

BACKGROUND: Transcription factor STAT3 has a prominent innate immunity effect on cancer progression. We determined the regulation of STAT3 in the immunophenotype modulation of macrophages from M1 into M2 induced by the cell-culture supernatant of the Prostate-Cancer line PC3. METHODS: Monocytes-macrophages from healthy donors were cultured in the supernatant of PC3 cells, membrane proteins, and intracytoplasmic and phosphorylated STAT3 were measured using flow cytometry, while cytokines and growth factors were studied using luminescence. Cytotoxicity and nitric oxide were evaluated via colorimetric assays. RESULTS: The supernatant of PC3 prostate-tumor cells effectively induced macrophages toward an M2 profile, and the expression of phosphorylated STAT3 in the monocytes-macrophages notably increased, and mainly related to IL-10. In the group of monocytes-macrophages treated with a STAT3 inhibitor, the macrophages were induced toward an M1 phenotype. CONCLUSIONS: In this study, we showed that the secretion profile of PC3 prostate-cancer cells induces a change in macrophage phenotype from M1 into M2, and that the phenomenon is related to phosphorylation of transcription factor STAT3 and IL-10.


Asunto(s)
Medios de Cultivo Condicionados/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Monocitos/inmunología , Factor de Transcripción STAT3/inmunología , Células Cultivadas , Humanos , Inmunofenotipificación , Interleucina-10/inmunología , Interleucina-10/metabolismo , Macrófagos/metabolismo , Masculino , Células PC-3 , Fosforilación/efectos de los fármacos , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Factor de Transcripción STAT3/metabolismo
7.
Cell Mol Biol (Noisy-le-grand) ; 63(1): 23-27, 2017 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-28234621

RESUMEN

Trypanosoma cruzi can compromise the human central nervous system (CNS) during acute infection or reactivation in immune-suppressed hosts. Astrocytes have been identified as targets of T. cruzi's CNS infection in humans. Despite a high degree of parasitism and cellular lysis by T. cruzi in vitro the number of astrocytoma cells did not change when compared to uninfected cultures. This work evaluated cellular proliferation, changes in Major Histocompatibility Complex (MHC) expression as a reflection of antigen processing, and cytokine (IL-6 & IL-8) secretion in a human astrocytoma cell line exposed to a trypomastigote-derived antigen. Light microscopy was used to evaluate the number of cells; MHC molecule expression, cell cycle and cytokine secretion were assessed by flow cytometry. The number of astrocytoma cells increased proportional to the amount of antigen used and the percentage of cells in G2/M phase was higher when compared to control cultures. Antigen exposure increased expression of MHC class II, but not MHC class I in comparison to cultures incubated without antigen. Astrocytoma cell secretion of IL-6 and IL-8 was unaffected by antigen exposure. These results suggest the participation of a trypomastigote-derived mediator that induces astrocytoma cell proliferation without an inflammatory response; which may contribute to the pathogenesis of neurologic Chagas disease.


Asunto(s)
Antígenos de Protozoos/farmacología , Trypanosoma cruzi/metabolismo , Astrocitoma/metabolismo , Astrocitoma/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Microscopía , Regulación hacia Arriba/efectos de los fármacos
8.
Clin Transl Oncol ; 18(4): 369-74, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26329293

RESUMEN

PURPOSE: Pentoxifylline (PTX) has been shown to increase chemotherapy-induced apoptosis. A clinical trial was developed to evaluate the effect of the addition of PTX to the induction steroid window phase in children with acute lymphoblastic leukemia (ALL). METHODS: Thirty-two children were enrolled on this study. Children with a new diagnosis of ALL were randomly assigned to receive prednisone (PRD) 40 mg/m(2)/day only during the 7-day treatment pre-phase (PRD group, 11 patients) or to receive PRD with PTX (10 mg/kg/day) (PTX group, 11 patients); the control group included children with normal bone marrow (10 patients). Bone marrow aspiration (BMA) was performed at diagnosis (day -7) in all groups, and at day 0 (end of PRD window) for patients with ALL (PRD and PTX groups). Apoptosis was evaluated by flow cytometry (FC) using Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) stains. Statistical analysis was performed using the Mann-Whitney U test. RESULTS: Apoptotic index at day -7 was similar in all groups. However, at day 0 post-treatment, apoptosis was significantly higher in the PTX group than in the PRD group (p < 0.001). There were no serious adverse effects associated with PTX. CONCLUSIONS: PTX potentiates blast apoptosis induced by PRD in children with ALL during steroid window phase.


Asunto(s)
Apoptosis/efectos de los fármacos , Pentoxifilina/uso terapéutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Prednisona/uso terapéutico , Adolescente , Antiinflamatorios/uso terapéutico , Niño , Preescolar , Quimioterapia Combinada , Femenino , Citometría de Flujo , Estudios de Seguimiento , Depuradores de Radicales Libres/uso terapéutico , Humanos , Lactante , Masculino , Estadificación de Neoplasias , Proyectos Piloto , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Inducción de Remisión
9.
J Perinatol ; 33(1): 15-20, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22481245

RESUMEN

OBJECTIVE: To evaluate the usefulness of serum lipid peroxide (LPO) for hypoxic ischemic encephalopathy (HIE) in full-term neonates. STUDY DESIGN: Diagnostic test evaluation forming three groups: (1) healthy full-term neonates (n=59), (2) at-risk full-term neonates without HIE (n=57) and (3) at-risk full-term neonates with HIE (n=57). HIE diagnosis was made using the Finer clinical classification at 48 h after birth. Serum LPO was taken at 4 h after birth and determined by spectrophotometry. RESULT: One hundred seventy-three full-term neonates were studied. Fifty-one of the at-risk full-term neonates with HIE (51/57) had high serum LPO and two of the at-risk full-term neonates without HIE (2/57) (P<0.001). Serum LPO level had 89% sensitivity, 96% specificity, 96% positive predictive value, 90% negative predictive value, 24 positive probability ratio, 0.11 negative probability ratio and 92% diagnostic usefulness. CONCLUSION: Serum LPO level could be a useful test for early diagnosis of HIE in full-term neonates.


Asunto(s)
Asfixia Neonatal/sangre , Asfixia Neonatal/diagnóstico , Hipoxia-Isquemia Encefálica/sangre , Hipoxia-Isquemia Encefálica/diagnóstico , Peróxidos Lipídicos/sangre , Puntaje de Apgar , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Masculino , Valor Predictivo de las Pruebas , Factores de Riesgo , Espectrofotometría
10.
Rev. colomb. cardiol ; 18(2): 111-118, mar.-abr. 2011.
Artículo en Español | LILACS | ID: lil-594831

RESUMEN

Este estudio tiene como objetivo evaluar la eficacia y seguridad de la terapia combinada de cardiomioplastia celular con el factor estimulante de colonias de granulocitos en pacientes con cardiopatía isquémica, y explorar posibles diferencias entre la vía de implantación. METODOLOGÍA: se hizo un estudio de ®antes y después¼ para datos longitudinales en el que se compararon variables ecocardiográficas y número de MET alcanzados en la prueba de esfuerzo antes, dos, seis y doce meses después del procedimiento; así mismo, se evaluaron la mortalidad y los efectos adversos de la terapia. Se exploraron diferencias en los resultados de acuerdo con la vía de implantación intracoronaria vs. epicárdica. RESULTADOS: se incluyeron dieciocho pacientes, 62,3% hombres, cuya edad promedio fue 49,4 ± 11,7 años y la fracción de eyección promedio fue 31% ± 0,04. La implantación se realizó por vía intracoronaria en doce pacientes y por vía epicárdica en seis. La mediana de fracción de eyección antes de la implantación de las células fue de 30% con un rango intercuartil de 28%-35% y la media de los MET fue de 6 con un rango intercuartil de 5-7; ambas variables, al igual que los volúmenes ventriculares de fin de diástole y sístole se incrementaron de forma significativa después del procedimiento, con tendencia a un mayor incremento de la fracción de eyección en el grupo de pacientes cuya vía de implantación fue la epicárdica en comparación con la vía intracoronaria; sin embargo, el número de pacientes en cada subgrupo impidió hacer análisis definitivos. Un paciente tuvo infección de la herida quirúrgica y tres murieron dos meses después de la implantación (uno de shock séptico y dos de shock cardiogénico)...


The objective of this study is to assess efficacy and safety of combined therapy of cellular cardiomyoplasty and granulocyte colony stimulating factor in patients with ischemic cardiomyopathy and explore possible differences between the implantation routes. METHODOLOGY: we performed a before and after study for longitudinal data comparing echocardiographic variables and number of Met achieved in the stress test before and at two, six and twelve months after the procedure. Likewise, mortality and adverse therapy effects were evaluated. Differences in the results were analyzed according to the intracoronary vs. epicardiac route of implantation. RESULTS: eighteen patients were included; 62,3% men, with mean age 49.4 ± 11,7 years. Mean ejection fraction was 31% ± 0,04. In twelve patients implantation was performed by intracoronary route and in six by epicardiac route. Mean ejection fraction before cell implantation was 30% with an interquartil range (IQR) of 28-35%, and MET average was 6 with an interquartil rage of 5-7. Both variables as well as end-systolic and end-diastolic volumes increased significantly after the procedure, with a tendency to greater increase in ejection fraction in the group of patients whose route was epicardial implantation compared with intracoronary route; however, the number of patients in each subgroup prevented to make a definitive analysis. One patient had surgical wound infection and three died two months after implantation (one of septic shock and two of cardiogenic shock). CONCLUSION: in our environment the performance of combination therapy with cellular cardiomyoplasty and granulocyte colony stimulating factor is feasible. This is a safe procedure that achieved a sustained improvement in ejection fraction and MET beyond benefits achieved with revascularization and optimal pharmacological therapy.


Asunto(s)
Enfermedad Coronaria , Factor Estimulante de Colonias de Granulocitos , Células Madre , Función Ventricular
11.
Parasite Immunol ; 32(7): 494-502, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20591120

RESUMEN

The K1 peptide is a CD8(+)T cell HLA-A*0201-restricted epitope derived from the Trypanosoma cruzi KMP-11 protein. We have previously shown that this peptide induces IFN-gamma secretion by CD8(+)T cells. The aim of this study was to characterize the frequency of K1-specific CD8(+)T cells in chagasic patients. Nineteen HLA-A2(+)individuals were selected from 50 T. cruzi infected patients using flow cytometry and SSP-PCR assays. Twelve HLA-A*0201(+)noninfected donors were included as controls. Peripheral blood mononuclear cells were stained with HLA-A2-K1 tetramer, showing that 15 of 19 infected patients have K1-specific CD8(+)T cells (0.09-0.34% frequency) without differences in disease stages or severity. Of note, five of these responders were A*0205, A*0222, A*0226, A*0259 and A*0287 after molecular typing. Thus, a phenotypic and functional comparison of K1-specific CD8(+)T cells from non-HLA-A*0201 and HLA-A*0201(+)infected patients was performed. The results showed that both non-HLA-A*0201 and HLA-A*0201(+)individuals have a predominant effector memory CD8(+)T cell phenotype (CCR7-, CD62L-). Moreover, CD8(+)T cells from non-HLA-A*0201 and HLA-A*0201(+)individuals expressed IL-2, IFN-gamma and perforin without any differences. These findings support that K1 peptide is a promiscuous epitope presented by HLA-A2 supertype molecules and is highly recognized by chagasic patients.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Enfermedad de Chagas/inmunología , Epítopos de Linfocito T/inmunología , Proteínas Protozoarias/inmunología , Trypanosoma cruzi/inmunología , Adulto , Anciano , Alelos , Femenino , Genotipo , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Humanos , Interferón gamma/biosíntesis , Interleucina-2/biosíntesis , Masculino , Persona de Mediana Edad , Perforina/biosíntesis
12.
Allergol Immunopathol (Madr) ; 38(4): 197-202, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20227159

RESUMEN

BACKGROUND: Papular urticaria caused by flea bite presents clinical symptoms of a hypersensitivity reaction accompanied by skin lesions. However, the pattern of recognition by different antibody isotypes during the progression of the disease is unknown. This study evaluated variations in immunoglobulin E and immunoglobulin G subclass antibody responses to flea antigens during the progression of papular urticaria caused by flea bite METHODS: Twenty-five patients clinically diagnosed with papular urticaria due to flea bite were included. Ten healthy children were included as controls. Recognition of antigens from complete flea body extract by patients and healthy controls was determined using immunoblot assays. RESULTS: The results revealed that patients with 2-5 years of papular urticaria evidenced more IgE bands than those with shorter or longer durations of symptoms. In contrast, healthy children showed a predominance of immunoglobulin G1 and immunoglobulin G3. The majority of the recognised antigens were low molecular weight proteins (<90 kDa). Proteins with molecular weights between 16-20, 21-25, and 31-35 kDa showed different patterns of recognition between patients and healthy children. CONCLUSION: The predominant specific antibody isotypes vary according to the time elapsed since the onset of symptoms in papular urticaria caused by flea bite.


Asunto(s)
Mordeduras y Picaduras/inmunología , Epítopos/inmunología , Inmunoglobulina E/inmunología , Inmunoglobulina G/inmunología , Adolescente , Animales , Mordeduras y Picaduras/complicaciones , Mordeduras y Picaduras/diagnóstico , Mordeduras y Picaduras/fisiopatología , Niño , Preescolar , Progresión de la Enfermedad , Epítopos/metabolismo , Femenino , Humanos , Lactante , Masculino , Siphonaptera , Enfermedades Cutáneas Vesiculoampollosas/diagnóstico , Enfermedades Cutáneas Vesiculoampollosas/etiología , Enfermedades Cutáneas Vesiculoampollosas/inmunología , Enfermedades Cutáneas Vesiculoampollosas/fisiopatología , Urticaria/diagnóstico , Urticaria/etiología , Urticaria/inmunología , Urticaria/fisiopatología
13.
Mem Inst Oswaldo Cruz ; 104(3): 468-72, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19547874

RESUMEN

The most frequent mutations associated with rifampin and isoniazid resistance in Mycobacterium are the substitutions at codons 531 and 315 in the rpoB and katG genes, respectively. Hence, the aim of this study was to characterize these mutations in Mycobacterium isolates from patients suspected to be infected with drug-resistant (DR) pulmonary tuberculosis (TB) in Veracruz, Mexico. Drug susceptibility testing of 25 clinical isolates revealed that five were susceptible while 20 (80%) were DR (15% of the annual prevalence for Veracruz). Of the DR isolates, 15 (75%) were resistant to rifampin, 17 (85%) to isoniazid and 15 (75%) were resistant to both drugs (MDR). Sequencing analysis performed in the isolates showed that 14 (93%) had mutations in the rpoB gene; seven of these (47%) exhibited a mutation at 531 (S-->L). Ten (58%) of the 20 resistant isolates showed mutations in katG; nine (52%) of these 10 exhibited a mutation at 315 (S-->T). In conclusion, the DR profile of the isolates suggests a significant number of different DR-TB strains with a low frequency of mutation at codons 531 and 315 in rpoB and katG, respectively. This result leads us to consider different regions of the same genes, as well as other genes for further analysis, which is important if a genetic-based diagnosis of DR-TB is to be developed for this region.


Asunto(s)
Proteínas Bacterianas/genética , Catalasa/genética , Mycobacterium/genética , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Pulmonar/microbiología , Antituberculosos/farmacología , ARN Polimerasas Dirigidas por ADN , Humanos , México , Mutación/genética , Mycobacterium/efectos de los fármacos , Mycobacterium/aislamiento & purificación
14.
Mem. Inst. Oswaldo Cruz ; 104(3): 468-472, May 2009. tab
Artículo en Inglés | LILACS | ID: lil-517012

RESUMEN

The most frequent mutations associated with rifampin and isoniazid resistance in Mycobacterium are the substitutions at codons 531 and 315 in the rpoB and katG genes, respectively. Hence, the aim of this study was to characterize these mutations in Mycobacterium isolates from patients suspected to be infected with drug-resistant (DR) pulmonary tuberculosis (TB) in Veracruz, Mexico. Drug susceptibility testing of 25 clinical isolates revealed that five were susceptible while 20 (80 percent) were DR (15 percent of the annual prevalence for Veracruz). Of the DR isolates, 15 (75 percent) were resistant to rifampin, 17 (85 percent) to isoniazid and 15 (75 percent) were resistant to both drugs (MDR). Sequencing analysis performed in the isolates showed that 14 (93 percent) had mutations in the rpoB gene; seven of these (47 percent) exhibited a mutation at 531 (S[L). Ten (58 percent) of the 20 resistant isolates showed mutations in katG; nine (52 percent) of these 10 exhibited a mutation at 315 (S[T). In conclusion, the DR profile of the isolates suggests a significant number of different DR-TB strains with a low frequency of mutation at codons 531 and 315 in rpoB and katG, respectively. This result leads us to consider different regions of the same genes, as well as other genes for further analysis, which is important if a genetic-based diagnosis of DR-TB is to be developed for this region.


Asunto(s)
Humanos , Proteínas Bacterianas/genética , Catalasa/genética , Mycobacterium/genética , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Pulmonar/microbiología , Antituberculosos/farmacología , México , Mutación/genética , Mycobacterium/efectos de los fármacos , Mycobacterium/aislamiento & purificación
15.
Peptides ; 28(8): 1520-6, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17683828

RESUMEN

The K1 peptide is an HLA-A*0201-restricted cytotoxic epitope derived from the Trypanosoma cruzi KMP-11 protein, this being the etiological agent of Chagas' disease. This work describes the K1 peptide's secondary structure and its recognition by sera from chagasic patients. Circular dichroism and NMR spectroscopy analysis revealed that the K1 peptide adopts an alpha-helical conformation. Fifty-six percent of individuals had anti-K1 and 86% anti-KMP-11 antibodies by ELISA in the chronic Chagas' group and 28 and 68% in the indeterminate Chagas' group, respectively. By contrast, no reactivity was observed in sera from healthy individuals and tuberculosis patients. Antibody response subclass specificity to the K1 peptide was IgG1 and IgG3. Taken together these results support the idea that the K1 peptide acts as a B-cell-inducer epitope during Chagas' disease.


Asunto(s)
Antígenos de Protozoos/química , Proteínas Protozoarias/química , Proteínas Protozoarias/inmunología , Trypanosoma cruzi/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/genética , Enfermedad de Chagas/inmunología , Epítopos/química , Epítopos/genética , Humanos , Inmunoglobulina G/sangre , Isotipos de Inmunoglobulinas/sangre , Modelos Moleculares , Estructura Secundaria de Proteína , Proteínas Protozoarias/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Trypanosoma cruzi/genética
16.
An Pediatr (Barc) ; 64(2): 126-31, 2006 Feb.
Artículo en Español | MEDLINE | ID: mdl-16527064

RESUMEN

INTRODUCTION: There is some evidence that retinopathy of prematurity is due to excessive oxidative stress on the developing retina caused by high free radical production or reduced ability to eliminate these radicals. OBJECTIVE: To determine the relationship between high levels of oxidative stress and retinopathy of prematurity. MATERIAL AND METHODS: A prospective cohort study was designed. Fifty premature infants of less than 33 weeks' gestational age were included. Serum lipoperoxide levels were determined as a measure of oxidative stress. Samples were taken once a week for 1 month, starting from the first week of life. The results of all four samples were compared between infants who developed any degree of retinopathy of prematurity and those without it. Ophthalmological examinations were performed after the fourth week of life. RESULTS: The incidence of retinopathy of prematurity was 22 % (11/50). The mean values of all the samples showed a significant difference between infants who developed retinopathy of prematurity (5.44 +/- 1.30 nmol/ml) and those who did not (2.94 +/- 0.89 nmol/ml, p = 0.0001). The relative risk of developing retinopathy of prematurity with high serum lipoperoxide levels was 5.15, 5.63, 4.15 and 12.70 for each of the weekly samples. CONCLUSIONS: There is an association between high serum lipoperoxide levels, as a measure of oxidative stress, and the incidence of retinopathy of prematurity.


Asunto(s)
Peróxidos Lipídicos/sangre , Estrés Oxidativo , Retinopatía de la Prematuridad/sangre , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Estudios Prospectivos , Retinopatía de la Prematuridad/etiología
17.
In. III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings. Anais. João Pessoa, SBEB, 2004. p.1555-1558, 1 CD-ROM - III Congresso Latino Americano de Engenharia Biomédica - CLAEB / International Federation for Medical and Biological Engineering - IFMBE Proceedings, ilus.
Monografía en Inglés | LILACS | ID: lil-540469

RESUMEN

One of the main goals in ultrasonic Doppler blood flow assessment in the estimation of the mean speed. The aim of this work is focused in Carotid artery blood flow signals...


Asunto(s)
Algoritmos , Arterias Carótidas , Ecocardiografía Doppler , Distribución Normal , Procesamiento de Señales Asistido por Computador
18.
J Nutr Biochem ; 12(7): 396-403, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11448615

RESUMEN

This study was undertaken with the aim of investigating the effect of sucrose addition to the drinking water of rats who were fed with the same diet as a control group, on Delta9- and Delta5-desaturase activities and on the fatty acid composition of serum and liver microsomes. Weanling male Wistar rats had 30% sucrose in their drinking water for 20 weeks. An increase in total calories consumed, visceral fat accumulation, insulin, triglycerides and blood pressure and a decrease in the food intake were observed in the sucrose-fed group as compared with the control group. A decrease in linoleic and alpha-linolenic acid (essential fatty acids) in all serum lipid fractions of sucrose-fed rats was found. This observation correlated with a low food intake by sucrose-fed rats. The conversion of [1 (14)C]-palmitic to [1 (14)C]-palmitoleic acid by Delta9-desaturase activity was increased in sucrose-fed compared with control rats, while the conversion of [1 (14)C]-dihomo-gamma-linolenic acids by Delta5-desaturase activity was depressed. In sucrose-fed as compared to control rats, the proportion of palmitoleic and oleic fatty acids was increased. Arachidonic acid was decreased in sucrose-fed rats. The 1,6-diphenylhexatriene fluorescence polarization of the microsomal membranes was significantly lower in the sucrose-fed group compared to the control group. These results indicate that the sucrose addition to the drinking water of the rats increased microsomal Delta9-desaturase activity and membrane disorder and decreased the activity of the Delta5-desaturase, a key enzyme in the biosynthesis of arachidonic acid, implicated in hypertension.

19.
Vet Parasitol ; 93(1): 29-38, 2000 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11027858

RESUMEN

A cross-sectional study was done of seroprevalence of Babesia bigemina, B.bovis, and Anaplasma marginale in cattle from eastern Bolivia, to characterise the risk of tick-borne disease in three ecological zones. Nineteen farms were sampled in the subtropical humid zone, 13 in the dry subtropical zone and nine in the lower western valleys of the Andean massif. The enzyme-linked immunosorbent assay was used. All three pathogens were widespread. For B. bovis, seroprevalences were high (75-78%) in the two subtropical zones which thus had low risk of disease from this infection; but the western valleys were endemically unstable with higher risk. For B. bigemina, seroprevalences were lower (24-57%) in the two subtropical zones and thus these areas were endemically unstable for disease from this infection. However, the seroprevalence of B. bigemina in the western valleys was too low (13%) for risk of disease in susceptible cattle to be considered high. For A. marginale, the seroprevalences in the two subtropical zones were low (19-32%) and very low (6%) in the western valleys suggesting all these zones were endemically unstable for anaplasmosis. Data for individual farms were analysed for risk of both forms of babesiosis; this showed low risk of disease in the subtropical humid zone, higher risk in the dry subtropical zone and variable risk in the western valleys.


Asunto(s)
Anaplasmosis/epidemiología , Babesiosis/epidemiología , Enfermedades de los Bovinos/epidemiología , Agricultura , Animales , Bolivia/epidemiología , Bovinos , Estudios Transversales , Factores de Riesgo , Estudios Seroepidemiológicos
20.
Ear Nose Throat J ; 79(12): 942-4, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11191432

RESUMEN

We retrospectively studied biopsy specimens obtained from 16 patients who had carcinoma of the tonsil or nasopharynx. Polymerase chain reaction testing detected the presence of human papillomavirus (HPV) in 13 samples (81.3%)--six tonsillar and seven nasopharyngeal. Eleven of the 13 positive samples (84.6%) contained HPV subtype 31. We believe that this is the first report of the presence of HPV subtype 31 in these carcinomas. In addition to the significant association between tonsillar and nasopharyngeal cancer and HPV, our analysis of descriptive variables confirmed the association between the incidence of these neoplasms and poor oral hygiene and low socioeconomic status in older adults.


Asunto(s)
Carcinoma/virología , Neoplasias Nasofaríngeas/virología , Papillomaviridae/clasificación , Infecciones por Papillomavirus/diagnóstico , Neoplasias Tonsilares/virología , Infecciones Tumorales por Virus/diagnóstico , Anciano , Biopsia con Aguja , Carcinoma/patología , Técnicas de Cultivo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/patología , Papillomaviridae/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Estudios Retrospectivos , Sensibilidad y Especificidad , Neoplasias Tonsilares/patología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA