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1.
Genet Mol Res ; 15(2)2016 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-27323163

RESUMEN

We investigated dynamic changes in T-lymphocyte subsets after hyperthermic intraperitoneal chemotherapy (HIPEC) or radiotherapy using flow cytometry. A total of 1423 lung cancer patients admitted to our hospital between October 2012 and July 2015 were enrolled, and age-matched healthy individuals served as controls. Peripheral blood mononuclear cells (PBMCs) were purified using standard Ficoll density gradient centrifugation, based on which CD3+, CD4+, and CD8+ T-cells were isolated. A surface marker was identified by flow cytometry. Immunohistochemical analysis determined the distribution of the cells in the tumor mass or adjacent tissues. A total of 957 patients (male: 555; female: 402; median age: 49.3 years) with lung cancer who had received only HIPEC or radiotherapy were enrolled. The patients were followed-up until death. No statistical difference was noticed between the patients who had received chemotherapy compared with the baseline levels. A remarkable elevation was noticed in the CD3+ T-cells in the patients three months after radiotherapy (78.71 ± 9.36 vs 68.15 ± 9.65, P < 0.05). The level of CD8+ in the patients who had received chemotherapy or radiotherapy was remarkably elevated in the post-treatment period (P < 0.05). The CD3+ and CD8+ T-cells were mainly expressed in the cytoplasm rather than in the adjacent tissues. The expression of CD3+ and CD4+ was correlated to tumor infiltration and metastasis. Remarkable elevation was noticed in the CD3+ T-cells in the patients three months after radiotherapy. The expression of CD3+ and CD4+ was negatively correlated to tumor infiltration and metastasis in non-small-cell lung cancer patients.


Asunto(s)
Leucocitos Mononucleares/inmunología , Neoplasias Pulmonares/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología , Adulto , Anciano , Femenino , Citometría de Flujo , Humanos , Hipertermia Inducida , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/efectos de la radiación , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/efectos de la radiación , Linfocitos T/efectos de los fármacos , Linfocitos T/patología , Linfocitos T/efectos de la radiación
2.
Toxicol Mech Methods ; 26(6): 427-34, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27098213

RESUMEN

Electronic cigarettes (e-cigarettes) are becoming the fashionable alternative to decrease tobacco smoking, although their impact on health has not been fully assessed yet. The present study was designed to compare the impact of e-cigarette refill liquid (e-liquid) without nicotine to e-liquid with nicotine on rat testis. For this purpose, e-liquid with nicotine and e-liquid without nicotine (0.5 mg/kg of body weight) were administered to adult male Wistar rats via the intraperitoneally route during four weeks. Results showed that e-liquid with or without nicotine leads to diminished sperm density and viability, such as a decrease in testicular lactate dehydrogenase activity and testosterone level. Furthermore, quantitative real-time polymerase chain reaction (qRT-PCR) analysis identified a reduction in cytochrome P450 side-chain cleavage (P450 scc) and 17 beta-hydroxysteroid dehydrogenase (17ßHSD) mRNA level, two key enzymes of steroidogenesis. Following e-liquid exposure, histopathological examination showed alterations in testis tissue marked by germ cells desquamation, disorganization of the tubular contents of testis and cell deposits in seminiferous tubules. Finally, analysis of oxidative stress status pointed an outbreak of antioxidant enzyme activities such as superoxide dismutase, catalase and gluthatione-S-transferase, as well as an important increase in sulfhydril group content. Taken together, these results indicate that e-liquid per se induces toxicity in Wistar rat testis, similar to e-liquid with nicotine, by disrupting oxidative balance and steroidogenesis.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina/efectos adversos , Nicotina/toxicidad , Estrés Oxidativo/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Animales , Biomarcadores/sangre , Inyecciones Intraperitoneales , L-Lactato Deshidrogenasa/sangre , Masculino , Nicotina/administración & dosificación , Ratas Wistar , Recuento de Espermatozoides , Espermatozoides/patología , Testículo/enzimología , Testículo/patología , Testosterona/sangre
3.
Genet Mol Res ; 14(3): 11488-94, 2015 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-26436389

RESUMEN

A case-control study was conducted to investigate the association between genetic variants of IL-17A rs2275913 and IL-17F rs763780 and the development of coronary artery disease (CAD) in a Chinese population. A total of 306 individuals with CAD and 306 unaffected individuals were enrolled from the Zhengzhou People's Hospital between May 2012 and May 2014. The IL-17A rs2275913 and IL-17F rs763780 genes were genotyped by polymerase chain reaction combined with a restriction fragment length polymorphism (PCR-RFLP). Logistic regression analysis revealed that individuals with the AA genotype of rs2275913 were associated with increased risk of CAD, compared to those with the GG genotype in a codominant model [adjusted odds ratio (OR) = 1.96; 95% confidence interval (CI) = 1.10-3.53]. On the other hand, the AA genotype of rs2275913 was correlated with moderately increased risk of CAD compared to the GG + GA genotype (adjusted OR = 1.76; 95%CI = 1.02-3.07) in a recessive model. However, no significant differences were observed between polymorphisms at the IL-17F rs763780 locus and CAD risk, in codominant, dominant, and recessive models. In conclusion, the results of our study suggested that the IL-17A rs2275913 polymorphism may affect the development of CAD; however, no significant association was observed between the IL-17F rs763780 polymorphism and risk of CAD.


Asunto(s)
Enfermedad de la Arteria Coronaria/genética , Predisposición Genética a la Enfermedad , Interleucina-17/genética , Polimorfismo de Nucleótido Simple/genética , Estudios de Casos y Controles , Demografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
4.
Genet Mol Res ; 14(1): 898-905, 2015 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-25730028

RESUMEN

We investigated the clinical efficacy of adoptive cytokine-induced killer (CIK) cell and dendritic cell (DC) therapy plus intensity-modulated radiation therapy (IMRT) for treating elderly patients with esophageal carcinoma (EC). In total, 68 elderly patients with EC were randomized to receive IMRT plus DC-CIK immunotherapy (study group, N = 34) or IMRT only (control group, N = 34). Clinical efficacy, immune function, toxicity and side effects, and life quality were evaluated after treatment. The efficacy rate was significantly higher in the study group than in the control group. Remarkable increases were noted for quality of life and immune function in the study group relative to the control group. Regarding toxicity and side effects, compared with the control group, the study group displayed a higher fever rate, a lower incidence rate of bone marrow suppression, and a similar rate of digestive tract reactions. DC-CIK immunotherapy plus IMRT exhibited better short-term efficacy than IMRT alone in elderly patients with EC. The therapy could improve patients'quality of life and immune function, decrease bone marrow suppression, and lengthen survival time.


Asunto(s)
Carcinoma/radioterapia , Tratamiento Basado en Trasplante de Células y Tejidos , Células Asesinas Inducidas por Citocinas/trasplante , Neoplasias Esofágicas/radioterapia , Anciano , Carcinoma/inmunología , Carcinoma/patología , Células Asesinas Inducidas por Citocinas/inmunología , Células Dendríticas/inmunología , Células Dendríticas/trasplante , Neoplasias Esofágicas/inmunología , Neoplasias Esofágicas/patología , Femenino , Humanos , Inmunoterapia/efectos adversos , Masculino , Persona de Mediana Edad , Radioterapia de Intensidad Modulada/efectos adversos
5.
J Anim Breed Genet ; 131(5): 379-86, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24373066

RESUMEN

The study characterized genetic diversity and genetic structure of five indigenous pig populations (Ha Lang, Muong Te, Mong Cai, Lung and Lung Pu), two wild pig populations (Vietnamese and Thai wild pigs) and an exotic pig breed (Yorkshire) using FAO/ISAG recommended 16 microsatellite markers in 236 samples. All estimated loci were very polymorphic indicated by high values of polymorphism information content (from 0.76 in S0225 to 0.92 in Sw2410). Indigenous populations had very high level of genetic diversity (mean He = 0.75); of all indigenous breeds, Lung Pu showed highest mean number of alleles (MNA = 10.1), gene diversity (He = 0.82), allele richness (5.33) and number of private alleles (10). Thirteen percentage of the total genetic variation observed was due to differences among populations. The neighbour-joining dendrogram obtained from Nei's standard genetic distance differentiated eight populations into four groups including Yorkshire, two wild populations, Mong Cai population and a group of four other indigenous populations. The Bayesian clustering with the admixture model implemented in Structure 2.1 indicated seven possible homogenous clusters among eight populations. From 79% (Ha Lang) to 98% (Mong Cai). individuals in indigenous pigs were assigned to their own populations. The results confirmed high level of genetic diversity and shed a new light on genetic structure of Vietnam indigenous pig populations.


Asunto(s)
Polimorfismo Genético , Porcinos/genética , Animales , Genotipo , Repeticiones de Microsatélite , Vietnam
6.
Med Trop (Mars) ; 71(3): 286-8, 2011 Jun.
Artículo en Francés | MEDLINE | ID: mdl-21870560

RESUMEN

OBJECTIVE: In response to the lack of cancer register and paucity of publications on esophageal cancer in Senegal, this retrospective descriptive single-center study was undertaken to determine epidemiological, clinical, endoscopic and histological features of the disease at a digestive endoscopy center in Dakar. PATIENTS AND METHOD: Reports describing upper digestive tract endoscopy procedures performed at the Aristide Le Dantec Teaching Hospital in Dakar between January 2006 and December 2009 were reviewed. Cases involving histologically confirmed esophageal cancer were compiled and patient data including age, sex, and indication for endoscopy as well as endoscopic and histological findings were analyzed. RESULTS: A total of 78 reports were collected including 76 patients with suitable data for analysis. Esophageal cancer accounted for 0.97% of upper digestive tract endoscopy procedures performed. Mean patient age was 49 years and the sex-ratio was 1.9. The main indication for endoscopy was dysphagia (92.1%). The most frequent endoscopic finding involved budding lesions with (42%) or without (29%) ulceration. The most common location was the middle third of the esophagus (50%). The most frequent histological type was squamous cell carcinoma (92.1%). CONCLUSION: Esophageal cancer observed at the endoscopy center of the Aristide Le Dantec Teaching Hospital in Dakar mainly affects young male adults. Lesions are generally located in the middle third of the esophagus and corresponded to squamous cell cancer. There is a need to establish a cancer register and to conduct multicentric studies to gain insight into risk factors for esophageal cancer in Senegal.


Asunto(s)
Neoplasias Esofágicas/patología , Esofagoscopía , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/patología , Niño , Trastornos de Deglución/etiología , Neoplasias Esofágicas/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Senegal/epidemiología , Adulto Joven
7.
J Chem Theory Comput ; 17(10): 6240-6261, 2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34516741

RESUMEN

The nonpolarizable CHARMM force field is one of the most widely used energy functions for all-atom biomolecular simulations. Chloride is the only halide ion included in the latest version, CHARMM36m, and is used widely in simulation studies, often as an electrolyte ion but also as the biological substrate of transport proteins and enzymes. Here, we find that existing parameters systematically underestimate the interaction of Cl- with proteins and lipids. Accordingly, when examined in solution, little to no Cl-association can be observed with most components of the protein, including backbone, polar side chains and aromatic rings. The strength of the interaction with cationic side chains and with alkali ions is also incongruent with experimental measurements, specifically osmotic coefficients of concentrated solutions. Consistent with these findings, a 4-µs trajectory of the Cl--specific transport protein CLC-ec1 shows irreversible Cl- dissociation from the so-called Scen binding site, even in a 150 mM NaCl buffer. To correct for these deficiencies, we formulate a series of pair-specific Lennard-Jones parameters that override those resulting from the conventional Lorentz-Berthelot combination rules. These parameters, referred to as NBFIX, are systematically calibrated against available experimental data as well as ab initio geometry optimizations and energy evaluations, for a wide set of binary and ternary Cl- complexes with protein and lipid analogs and alkali cations. Analogously, we also formulate parameter sets for the other three biological halide ions, namely, fluoride, bromide, and iodide. The resulting parameters are used to calculate the potential of mean force defining the interaction of each anion and each of the protein and lipid analogues in bulk water, revealing association free energies in the range of -0.3 to -3.3 kcal/mol, with the F- complexes being the least stable. The NBFIX corrections also preserve the Cl- occupancy of CLC-ec1 in a second 4-µs trajectory. We posit that these optimized molecular-mechanics models provide a more realistic foundation for all-atom simulation studies of processes entailing changes in hydration, recognition, or transport of halide anions.


Asunto(s)
Álcalis , Cloruros , Lípidos/química , Proteínas/química , Aniones/química , Cationes/química , Fluoruros/química , Simulación de Dinámica Molecular , Termodinámica
8.
Klin Khir ; (8): 11-8, 2006 Aug.
Artículo en Ruso | MEDLINE | ID: mdl-17115606

RESUMEN

Lymphoedema--is a chronic disease, characterized by the volume enhancement of some part of body, more often--of the limbs, as a consequence of tissues oedema, caused by the lymphatic system transport and resorptive function disorder. Modern approaches to lymphoedema treatment foresees combination of conservative and surgical ones, for example, microsurgical, taking into account the oedema character, stage of the disease, the previous treatment efficacy.


Asunto(s)
Extremidad Inferior/fisiopatología , Linfedema/fisiopatología , Linfedema/cirugía , Microcirugia/métodos , Algoritmos , Enfermedad Crónica , Humanos , Estudios Retrospectivos
9.
J Med Chem ; 33(8): 2162-73, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2165163

RESUMEN

A series of acyclic and C-acyclic 7-deazapurine nucleosides have been synthesized and tested for antiviral activity. Reaction of the sodium salt of 2-amino-3,4-bis(aminocarbonyl)-5-(methylthio)pyrrole (6) with an appropriate electrophile gave pyrrole nucleosides which served as common intermediates to both the 7-deazaadenosine and the 7-deazaguanosine series. Several of these 5- and 5,6-substituted pyrrolo[2,3-d]pyrimidine nucleosides have shown activity against HIV virus in preliminary in vitro screens.


Asunto(s)
Antivirales/síntesis química , VIH/efectos de los fármacos , Nucleósidos de Pirimidina/síntesis química , Antivirales/farmacología , Fenómenos Químicos , Química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Nucleósidos de Pirimidina/farmacología , Pirroles/síntesis química , Pirroles/farmacología , Simplexvirus/efectos de los fármacos
10.
Hum Pathol ; 32(3): 327-32, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11274643

RESUMEN

There is growing evidence that senescent cells accumulate in vivo and are associated with the aging process in parallel with the progressive erosion of telomeres. Because recent data show that telomere shortening is involved in the pathogenesis of liver cirrhosis, we looked for replicative senescence cells in normal livers, chronic hepatitis C, and hepatocellular carcinoma (HCC). Replicative senescent cells were detected on liver tissue cryosections using expression of a specific marker, senescence-associated beta-galactosidase, a cytoplasmic enzyme detected at pH 6. A total of 57 frozen liver samples (15 normal liver, 32 chronic hepatitis C, and 10 HCCs) were studied. Replicative senescence was graded as absent in 56% of cases (32 of 57) and present in 44% (25 of 57). Replicative senescence was considered present in 3 of 15 normal livers (20%), 16 of 32 chronic hepatitis cases (50%), and 6 of 10 HCCs (60%). In the group of nontumoral livers, the presence of senescent cells in liver was associated with older age (P =.03). In the group with chronic hepatitis C, fibrosis stage, but not activity grade, was significantly correlated with the accumulation of replicative senescent cells (P <.001). Finally, beta-Gal staining in nontumoral tissue was strongly correlated with the presence of HCC in the surrounding liver (P <.001). These results suggest that chronic hepatitis C represents a relevant model of accelerated replicative senescence and that accumulation of replicative senescent cells predispose to HCC development. Detection of replicative senescent cells may then serve as a predictive marker of a hepatocellular carcinoma in the surrounding tissue. HUM PATHOL 32:327-332.


Asunto(s)
Carcinoma Hepatocelular/patología , División Celular , Senescencia Celular , Hepatitis C Crónica/patología , Neoplasias Hepáticas/patología , Hígado/patología , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Secciones por Congelación , Humanos , Concentración de Iones de Hidrógeno , Persona de Mediana Edad , Estudios Retrospectivos , Telómero/metabolismo , Telómero/patología , beta-Galactosidasa/análisis
11.
J Clin Pathol ; 51(11): 798-802, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10193318

RESUMEN

AIMS: To evaluate the role of CD44 in early steps in the development of prostate cancer, and to assess the biological significance of preneoplastic lesions in prostate cancer. METHODS: 38 patients with clinically localised prostate cancer were studied. The standard form of CD44 (CD44H) and v6 isoform expressions were semiquantitatively evaluated on paraffin embedded tumour tissue by immunohistochemistry. Disseminated prostatic cells were detected by prostate specific membrane antigen reverse transcriptase polymerase chain reaction in the blood of each patient before radical prostatectomy. RESULTS: In normal or benign prostate glands, only basal cells showed CD44H and v6 labelling. Fourteen of the 38 prostate cancers (37%) had CD44H membranous staining of prostatic tumour cells. In 18 patients (47%), circulating prostatic cells were detected in blood before surgery. Although no correlation between the expression of CD44 and the Gleason score or staging was observed, a significant correlation was found between the expression of CD44H by tumour cells and prostatic cell blood dissemination (p = 0.04). In 28 cases, foci of prostatic intraepithelial neoplasia were observed, and nine had CD44H immunostaining. CONCLUSIONS: De novo expression of CD44 by prostatic tumour cells is associated with systemic dissemination of prostate cells independently of pathological criteria.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Acinares/metabolismo , Receptores de Hialuranos/metabolismo , Células Neoplásicas Circulantes/metabolismo , Neoplasias de la Próstata/metabolismo , Adulto , Anciano , Progresión de la Enfermedad , Estudios de Seguimiento , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Neoplasia Intraepitelial Prostática/metabolismo , Neoplasias de la Próstata/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Virchows Arch ; 436(4): 351-6, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10834538

RESUMEN

Vascular endothelial growth factor (VEGF) is an angiogenic factor that may be involved in tumor growth and metastasis. Only a few data concerning the role of VEGF in renal cell carcinomas (RCCs) are available, and no studies have yet evaluated its prognostic value. The aim of the present study was to assess VEGF expression in a large series of renal tumors with a long follow-up, correlated with the usual histoprognostic factors and survival. VEGF immunostaining was performed on formalin-fixed, paraffin-embedded archival tissue from 74 renal carcinomas (62 conventional renal cell and 12 papillary carcinomas). Positivity of immunostaining was semi-quantitatively scored by two pathologists. Angiogenesis was evaluated by immunostaining with anti-CD34 antibodies on serial sections. Cytoplasmic VEGF expression was detected in tumor cells in 35% (26/74) of RCCs, including 18 out of the 62 (29%) conventional RCCs and 8 out of the 12 (67%) papillary carcinomas (P=0.02). In the group of conventional RCCs, VEGF expression was positively correlated with both nuclear grade (P=0.05) and size of the tumor (P=0.05). Furthermore, a significant correlation was observed between VEGF expression and microvascular count (P=0.04). Finally, cumulative survival rate was significantly lower in the group of patients with conventional RCCs expressing VEGF (log rank test, P=0.01). In the Cox model, VEGF expression was a significant independent predictor of outcome, as well as stage and nuclear grade. This study suggests that VEGF is involved in angiogenesis in conventional RCCs and appears to be a potential prognostic factor in these tumors.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Factores de Crecimiento Endotelial/metabolismo , Neoplasias Renales/metabolismo , Linfocinas/metabolismo , Vasos Sanguíneos/metabolismo , Carcinoma Papilar/irrigación sanguínea , Carcinoma Papilar/metabolismo , Carcinoma de Células Renales/irrigación sanguínea , Humanos , Inmunohistoquímica , Neoplasias Renales/irrigación sanguínea , Microcirculación , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Análisis de Supervivencia , Factor A de Crecimiento Endotelial Vascular , Factores de Crecimiento Endotelial Vascular
13.
Rev Epidemiol Sante Publique ; 29(3): 355-61, 1981.
Artículo en Inglés | MEDLINE | ID: mdl-7302317

RESUMEN

Epidemiological knowledge is essential to provide sound advice on the provision of health services. The role of the community physician in the UK can only be understood with reference to the structure of the National Health Service. His function at District level is illustrated by strategies of secondary prevention such as anti-smoking campaigns in the fight against cardio-respiratory disease, and the detection of hypertensives in out-patient departments. At national level decisions mainly concern priority. The need for reliable evaluative research to be done before policy decisions are made is evident from several studies undertaken at St. Thomas' Hospital, London, and to achieve this epidemiologists, planners and administrators must work closely together.


Asunto(s)
Métodos Epidemiológicos , Política de Salud , Formulación de Políticas , Medicina Comunitaria , Necesidades y Demandas de Servicios de Salud , Rol del Médico , Medicina Estatal/organización & administración , Reino Unido
14.
Klin Khir ; (3-4): 25-9, 1997.
Artículo en Ruso | MEDLINE | ID: mdl-9377248

RESUMEN

The diagnosis complex, permitting to reveal the disease cause and the character of the affect faulty and quickly, was elaborated, based on the experience of treatment analysis of more than 600 patients with the upper extremities neurovascular diseases--thoracic inlet syndrome, Raynaud disease and syndrome. Methods of conservative therapy are introduced, indications for operative treatment are substantiated. Application of new methods of restoration-reconstructive interventions permitted to raise the treatment quality, particularly in seriously ill patients with complicated forms of upper extremities neurovascular diseases.


Asunto(s)
Brazo/irrigación sanguínea , Brazo/inervación , Enfermedad de Raynaud/diagnóstico , Enfermedad de Raynaud/cirugía , Síndrome del Desfiladero Torácico/diagnóstico , Síndrome del Desfiladero Torácico/cirugía , Diagnóstico Diferencial , Susceptibilidad a Enfermedades , Humanos , Métodos , Enfermedad de Raynaud/complicaciones , Síndrome del Desfiladero Torácico/complicaciones
15.
Environ Entomol ; 41(5): 1255-67, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23068184

RESUMEN

We created a detailed model of the Maruca vitrata (F.) and cowpea [Vigna unguiculata (L.) Walp] system to study the possible evolution of resistance by the insect to transgenic insecticidal cowpea, which is under development. We focused on population dynamics and genetics in a region of west Africa. We simulated single-toxin and pyramided (two-toxin) cowpea and emphasized conservative, worst-case scenarios in our analysis. The results indicate that as long as a pyramided, transgenic cowpea can be developed, seed saving by farmers and reliance on natural refuge are not major problems for resistance management. Furthermore, it is possible that one or both toxins in the pyramid may not need to be high dose for evolution to be delayed significantly (>20 yr or 80 generations for resistance to become a concern if transgenic cowpea is deployed in areas where M. vitrata is endemic). If efforts are made to deploy transgenic cowpea only into the regions where M. vitrata is not endemic, then there is little to no concern with resistance emerging in the M. vitrata population.


Asunto(s)
Proteínas Bacterianas , Evolución Biológica , Endotoxinas , Proteínas Hemolisinas , Insecticidas , Modelos Biológicos , Mariposas Nocturnas/genética , África , Animales , Toxinas de Bacillus thuringiensis , Fabaceae/genética , Femenino , Herbivoria , Resistencia a los Insecticidas/genética , Masculino , Plantas Modificadas Genéticamente
17.
Pak J Biol Sci ; 12(19): 1320-4, 2009 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-20387747

RESUMEN

In Burkina Faso, farmers commonly use insecticidal plants for crop protection. To understand how insecticidal plant works (their mode of action), we carried out a bioassay on Clavigralla tomentosicollis, the cowpea pod sucking bugs with three insecticidal plants, Cassia nigricans V., Cymbopogon schoenanthus S. and Cleome viscosa L. Three modes of exposures (1) direct contact application, (2) stomach poisoning activity (3) and inhalation toxicity activity, were tested. The results showed a potent contact and stomach toxicity on 1st instars larvae regardless of the three crude extracts. But the plant extracts was less effective with older stages of the insects. A highest effectiveness was recorded with inhalation of vapours of crude extracts regardless of insect stages and type of plants. Implications of these findings are discussed regarding the use of plant extract for controlling pod sucking bugs in cowpea fields.


Asunto(s)
Cassia/metabolismo , Cleome/metabolismo , Cymbopogon/metabolismo , Hemípteros/efectos de los fármacos , Insecticidas/farmacología , Extractos Vegetales/farmacología , Animales , Evaluación Preclínica de Medicamentos , Larva/efectos de los fármacos , Control Biológico de Vectores/métodos , Plantas , Solventes/química , Estómago/efectos de los fármacos
18.
Genes Immun ; 8(4): 320-4, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17396103

RESUMEN

The host genetic background has been considered one of the factors that influence leprosy outcome, a chronic infectious disease caused by Mycobacterium leprae. Genome scans demonstrated that the 6p21 region is associated with leprosy and a substantial number of population-based studies analyzing human leukocyte antigen (HLA) class II loci suggested association of HLA-DR with leprosy. However, some studies lacked robustness as they had limited power. Indeed, experimental designs require increased sample size to achieve adequate power, as well as replication studies with independent samples for confirmation of previous findings. In this work, we analyzed the influence of the HLA-DRB1 locus on leprosy susceptibility per se and disease type using a case-control design carried out in Brazilians (578 cases and 691 controls) and a replication study based on a family design in a Vietnamese population (n=194 families). The results showed that HLA-DRB1*10 is associated with susceptibility to leprosy and HLA-DRB1*04 is associated with resistance, both in the Brazilian and Vietnamese populations suggesting that these alleles play an important role in the activation of cellular immune responses against M. leprae.


Asunto(s)
Predisposición Genética a la Enfermedad , Antígenos HLA-DR/genética , Lepra/genética , Lepra/inmunología , Alelos , Brasil , Cadenas HLA-DRB1 , Humanos , Inmunidad Innata , Vietnam
19.
Antimicrob Agents Chemother ; 50(2): 625-31, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16436719

RESUMEN

SPD754 (AVX754) is a deoxycytidine analogue nucleotide reverse transcriptase inhibitor (NRTI) in clinical development. These studies characterized the in vitro activity of SPD754 against NRTI-resistant human immunodeficiency virus type 1 (HIV-1) and non-clade B HIV-1 isolates, its activity in combination with other antiretrovirals, and its potential myelotoxicity and mitochondrial toxicity. SPD754 was tested against 50 clinical HIV-1 isolates (5 wild-type isolates and 45 NRTI-resistant isolates) in MT-4 cells using the Antivirogram assay. SPD754 susceptibility was reduced 1.2- to 2.2-fold against isolates resistant to zidovudine (M41L, T215Y/F, plus a median of three additional nucleoside analogue mutations [NAMs]) and/or lamivudine (M184V) and was reduced 1.3- to 2.8-fold against isolates resistant to abacavir (L74V, Y115F, and M184V plus one other NAM) or stavudine (V75T/M, M41L, T215F/Y, and four other NAMs). Insertions at amino acid position 69 and Q151M mutations (with or without M184V) reduced SPD754 susceptibility 5.2-fold and 14- to 16-fold, respectively (these changes gave values comparable to or less than the corresponding values for zidovudine, lamivudine, abacavir, and didanosine). SPD754 showed similar activity against isolates of group M HIV-1 clades, including A/G, B, C, D, A(E), D/F, F, and H. SPD754 showed additive effects in combination with other NRTIs, tenofovir, nevirapine, or saquinavir. SPD754 had no significant effects on cell viability or mitochondrial DNA in HepG2 or MT-4 cells during 28-day exposure at concentrations up to 200 microM. SPD754 showed a low potential for myelotoxicity against human bone marrow. In vitro, SPD754 retained activity against most NRTI-resistant HIV-1 clinical isolates and showed a low propensity to cause myelotoxicity and mitochondrial toxicity.


Asunto(s)
Fármacos Anti-VIH/farmacología , Desoxicitidina/análogos & derivados , Inhibidores de la Transcriptasa Inversa/farmacología , Médula Ósea/efectos de los fármacos , ADN Mitocondrial/análisis , Desoxicitidina/farmacología , Desoxicitidina/toxicidad , VIH-1/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos
20.
Drug Discov Today ; 5(10): 465-476, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11018598

RESUMEN

Nucleoside analogue inhibitors of the reverse transcriptase (RT) enzyme of HIV-1 were the first class of compounds to be used in anti-HIV-1 therapy and are a cornerstone in highly active antiretroviral therapy. Despite the number of inhibitors of HIV-1 RT available for clinical use at the present time and the effectiveness of these compounds in combination regimens, long-term exposure of patients to these drugs often results in the development of viral resistance or long-term toxicity. For this reason, efforts to identify new agents with activity against drug-resistant strains of HIV-1 and with a toxicity profile that allows for individual patient tolerance of the drugs are still warranted.

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