Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 378
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Gene Ther ; 23(1): 1-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26207935

RESUMEN

Gene therapy holds exceptional potential for translational medicine by improving the products of defective genes in diseases and/or providing necessary biologics from endogenous sources during recovery processes. However, validating methods for the delivery, distribution and expression of the exogenous genes from such therapy can generally not be applicable to monitor effects over the long term because they are invasive. We report here that human granulocyte colony-stimulating factor (hG-CSF) complimentary DNA (cDNA) encoded in self-complementary adeno-associated virus-type 2 adeno-associated virus, as delivered through eye drops at multiple time points after cerebral ischemia using bilateral carotid occlusion for 60 min (BCAO-60) led to significant reduction in mortality rates, cerebral atrophy and neurological deficits in C57black6 mice. Most importantly, we validated hG-CSF cDNA expression using translatable magnetic resonance imaging (MRI) in living brains. This noninvasive approach for monitoring exogenous gene expression in the brains has potential for great impact in the area of experimental gene therapy in animal models of heart attack, stroke, Alzheimer's dementia, Parkinson's disorder and amyotrophic lateral sclerosis, and the translation of such techniques to emergency medicine.


Asunto(s)
Isquemia Encefálica/terapia , Terapia Genética/métodos , Imagen por Resonancia Magnética , Neuroprotección , Animales , Encéfalo/metabolismo , Isquemia Encefálica/patología , Cerebro/patología , ADN Complementario/genética , ADN Complementario/metabolismo , Dependovirus/genética , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Vectores Genéticos , Factor Estimulante de Colonias de Granulocitos/genética , Factor Estimulante de Colonias de Granulocitos/metabolismo , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Soluciones Oftálmicas , Células PC12 , Oligonucleótidos Fosforotioatos/genética , Ratas
2.
Genes Immun ; 16(3): 213-20, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25633979

RESUMEN

Numerous reports have suggested that immunogenetic factors may influence human immunodeficiency virus (HIV)-1 acquisition, yet replicated findings that translate between study cohorts remain elusive. Our work aimed to test several hypotheses about genetic variants within the IL10-IL24 gene cluster that encodes interleukin (IL)-10, IL-19, IL-20 and IL-24. In aggregated data from 515 Rwandans and 762 Zambians with up to 12 years of follow-up, 190 single-nucleotide polymorphisms passed quality control procedures. When HIV-1-exposed seronegative subjects (n=486) were compared with newly seroconverted individuals (n=313) and seroprevalent subjects (n=478) who were already infected at enrollment, rs12407485 (G>A) in IL19 showed a robust association signal in adjusted logistic regression models (odds ratio=0.64, P=1.7 × 10(-4) and q=0.033). Sensitivity analyses demonstrated that (i) results from both cohorts and subgroups within each cohort were highly consistent; (ii) verification of HIV-1 infection status after enrollment was critical; and (iii) supporting evidence was readily obtained from Cox proportional hazards models. Data from public databases indicate that rs12407485 is part of an enhancer element for three transcription factors. Overall, these findings suggest that molecular features at the IL19 locus may modestly alter the establishment of HIV-1 infection.


Asunto(s)
Cromosomas Humanos Par 1 , Susceptibilidad a Enfermedades , Elementos de Facilitación Genéticos , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , Interleucinas/genética , Adulto , Alelos , Población Negra , Estudios de Cohortes , Biología Computacional , Femenino , Estudios de Seguimiento , Genotipo , Infecciones por VIH/mortalidad , Infecciones por VIH/virología , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Polimorfismo de Nucleótido Simple , Adulto Joven
3.
Tissue Antigens ; 85(2): 117-26, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25626602

RESUMEN

The RV144 HIV vaccine trial in Thailand elicited antibody responses to the envelope of HIV-1, which correlated significantly with the risk of HIV-1 acquisition. Human leukocyte antigen (HLA) class II molecules are essential in antigen presentation to CD4 T cells for activation of B cells to produce antibodies. We genotyped the classical HLA-DRB1, DQB1, and DPB1 genes in 450 individuals from the placebo arm of the RV144 study to determine the background allele and haplotype frequencies of these genes in this cohort. High-resolution 4 and 6-digit class II HLA typing data was generated using sequencing-based methods. The observed diversity for the HLA loci was 33 HLA-DRB1, 15 HLA-DQB1, and 26 HLA-DPB1 alleles. Common alleles with frequencies greater than 10% were DRB1*07:01, DRB1*09:01, DRB1*12:02, DRB1*15:02, DQB1*02:01/02, DQB1*03:01, DQB1*03:03, DQB1*05:01, DQB1*05:02, DPB1*04:01:01, DPB1*05:01:01, and DPB1*13:01:01. We identified 28 rare alleles with frequencies of less than 1% in the Thai individuals. Ambiguity for HLA-DPB1*28:01 in exon 2 was resolved to DPB1*296:01 by next-generation sequencing of all exons. Multi-locus haplotypes including HLA class I and II loci were reported in this study. This is the first comprehensive report of allele and haplotype frequencies of all three HLA class II genes from a Thai population. A high-resolution genotyping method such as next-generation sequencing avoids missing rare alleles and resolves ambiguous calls. The HLA class II genotyping data generated in this study will be beneficial not only for future disease association/vaccine efficacy studies related to the RV144 study, but also for similar studies in other diseases in the Thai population, as well as population genetics and transplantation studies.


Asunto(s)
Vacunas contra el SIDA/inmunología , Variación Genética , Infecciones por VIH/genética , Infecciones por VIH/inmunología , VIH-1/inmunología , Antígenos de Histocompatibilidad Clase II/genética , Alelos , Frecuencia de los Genes , Cadenas beta de HLA-DP/genética , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Haplotipos/genética , Humanos , Placebos , Tailandia , Resultado del Tratamiento
4.
Genes Immun ; 15(5): 275-81, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24784026

RESUMEN

Multiple major histocompatibility complex (MHC) loci encoding human leukocyte antigens (HLA) have allelic variants unequivocally associated with differential immune control of HIV-1 infection. Fine mapping based on single nucleotide polymorphisms (SNPs) in the extended MHC (xMHC) region is expected to reveal causal or novel factors and to justify a search for functional mechanisms. We have tested the utility of a custom fine-mapping platform (the ImmunoChip) for 172 HIV-1 seroconverters (SCs) and 449 seroprevalent individuals (SPs) from Lusaka, Zambia, with a focus on more than 6400 informative xMHC SNPs. When conditioned on HLA and nongenetic factors previously associated with HIV-1 viral load (VL) in the study cohort, penalized approaches (HyperLasso models) identified an intergenic SNP (rs3094626 between RPP21 and HLA-E) and an intronic SNP (rs3134931 in NOTCH4) as novel correlates of early set-point VL in SCs. The minor allele of rs2857114 (downstream from HLA-DOB) was an unfavorable factor in SPs. Joint models based on demographic features, HLA alleles and the newly identified SNP variants could explain 29% and 15% of VL variance in SCs and SPs, respectively. These findings and bioinformatics strongly suggest that both classic and nonclassic MHC genes deserve further investigation, especially in Africans with relatively short haplotype blocks.


Asunto(s)
Infecciones por VIH/genética , Desequilibrio de Ligamiento , Complejo Mayor de Histocompatibilidad/genética , Polimorfismo de Nucleótido Simple , Adulto , África , Femenino , Infecciones por VIH/inmunología , VIH-1/patogenicidad , Humanos , Masculino , Carga Viral
5.
Hernia ; 28(1): 25-31, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37682377

RESUMEN

PURPOSE: We sought to compare females and males for the risk of reoperation following different inguinal hernia repair approaches (open, laparoscopic, and robotic). METHODS: We conducted a retrospective cohort study including all patients aged ≥ 18 who underwent first inguinal hernia repair with mesh within a US integrated healthcare system (2010-2020). Data were obtained from the system's integrated electronic health record. Multiple Cox proportional-hazards regression was used to evaluate the association between sex and risk for ipsilateral reoperation during follow-up. Analysis was stratified by surgical approach (open, laparoscopic, and robotic). RESULTS: The study cohort was comprised of 110,805 patients who underwent 131,626 inguinal hernia repairs with mesh, 10,079 (7.7%) repairs were in females. After adjustment for confounders, females had a higher risk of reoperation than males following open groin hernia repair (hazard ratio [HR] = 1.98, 95% CI 1.74-2.25), but a lower reoperation risk following laparoscopic repair (HR = 0.70, 95% CI 0.51-0.97). The crude 5-year cumulative reoperation probability following robotic repair was 2.8% in males and no reoperations were observed for females. Of females who had a reoperation, 10.3% (39/378) were for a femoral hernia, while only 0.6% (18/3110) were for femoral hernias in males. CONCLUSION: In a large multi-center cohort of mesh-based inguinal hernia repair patients, we found a higher risk for reoperation in females after an open repair approach compared to males. Lower risk was observed for females through a minimally invasive approach (laparoscopic or robotic) and may be due to the ability to identify an occult femoral hernia through these approaches.


Asunto(s)
Prestación Integrada de Atención de Salud , Hernia Femoral , Hernia Inguinal , Adulto , Masculino , Humanos , Femenino , Reoperación , Estudios de Cohortes , Estudios Retrospectivos , Hernia Inguinal/cirugía , Hernia Inguinal/etiología , Hernia Femoral/cirugía , Mallas Quirúrgicas/efectos adversos , Herniorrafia/efectos adversos , Recurrencia
6.
J Virol ; 86(10): 5452-66, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22419811

RESUMEN

Dendritic cells (DC) are potent antigen-presenting cells and central to the induction of immune responses following infection or vaccination. The collection of DC migrating from peripheral tissues by cannulation of the afferent lymphatic vessels provides DC which can be used directly ex vivo without extensive in vitro manipulations. We have previously used bovine migrating DC to show that recombinant human adenovirus 5 vectors efficiently transduce afferent lymph migrating DEC-205(+) CD11c(+) CD8(-) DC (ALDC). We have also shown that recombinant modified vaccinia virus Ankara (MVA) infects ALDC in vitro, causing downregulation of costimulatory molecules, apoptosis, and cell death. We now show that in the bovine system, modified vaccinia virus Ankara-induced apoptosis in DC draining from the skin occurs soon after virus binding via the caspase 8 pathway and is not associated with viral gene expression. We also show that after virus entry, the caspase 9 pathway cascade is initiated. The magnitude of T cell responses to mycobacterial antigen 85A (Ag85A) expressed by recombinant MVA-infected ALDC is increased by blocking caspase-induced apoptosis. Apoptotic bodies generated by recombinant MVA (rMVA)-Ag85A-infected ALDC and containing Ag85A were phagocytosed by noninfected migrating ALDC expressing SIRPα via actin-dependent phagocytosis, and these ALDC in turn presented antigen. However, the addition of fresh ALDC to MVA-infected cultures did not improve on the magnitude of the T cell responses; in contrast, these noninfected DC showed downregulation of major histocompatibility complex class II (MHC-II), CD40, CD80, and CD86. We also observed that MVA-infected ALDC promoted migration of DEC-205(+) SIRPα(+) CD21(+) DC as well as CD4(+) and CD8(+) T cells independently of caspase activation. These in vitro studies show that induction of apoptosis in DC by MVA vectors is detrimental to the subsequent induction of T cell responses.


Asunto(s)
Presentación de Antígeno , Apoptosis , Caspasas/metabolismo , Células Dendríticas/citología , Tuberculosis/inmunología , Virus Vaccinia/inmunología , Vacunas Virales/inmunología , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Caspasas/genética , Caspasas/inmunología , Bovinos , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Regulación hacia Abajo , Vectores Genéticos/genética , Vectores Genéticos/inmunología , Humanos , Mycobacterium bovis/genética , Mycobacterium bovis/inmunología , Transducción de Señal , Tuberculosis/enzimología , Tuberculosis/fisiopatología , Tuberculosis/virología , Virus Vaccinia/genética , Virus Vaccinia/fisiología , Vacunas Virales/genética
7.
Hernia ; 27(5): 1209-1223, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37148362

RESUMEN

PURPOSE: The aim of this study was to describe a cohort of patients who underwent inguinal hernia repair within a United States-based integrated healthcare system (IHS) and evaluate the risk for postoperative events by surgeon and hospital volume within each surgical approach, open, laparoscopic, and robotic. METHODS: Patients aged ≥ 18 years who underwent their first inguinal hernia repair were identified for a cohort study (2010-2020). Average annual surgeon and hospital volume were broken into quartiles with the lowest volume quartile as the reference group. Multiple Cox regression evaluated risk for ipsilateral reoperation following repair by volume. All analyses were stratified by surgical approach (open, laparoscopic, and robotic). RESULTS: 110,808 patients underwent 131,629 inguinal hernia repairs during the study years; procedures were performed by 897 surgeons at 36 hospitals. Most repairs were open (65.4%), followed by laparoscopic (33.5%) and robotic (1.1%). Reoperation rates at 5 and 10 years of follow-up were 2.4% and 3.4%, respectively; rates were similar across surgical groups. In adjusted analysis, surgeons with higher laparoscopic volumes had a lower reoperation risk (27-46 average annual repairs: hazard ratio [HR] = 0.63, 95% confidence interval [CI] 0.53-0.74; ≥ 47 repairs: HR 0.53, 95% CI 0.44-0.64) compared to those in the lowest volume quartile (< 14 average annual repairs). No differences in reoperation rates were observed in reference to surgeon or hospital volume following open or robotic inguinal hernia repair. CONCLUSION: High-volume surgeons may reduce reoperation risk following laparoscopic inguinal hernia repair. We hope to better identify additional risk factors for inguinal hernia repair complications and improve patient outcomes with future studies.


Asunto(s)
Hernia Inguinal , Laparoscopía , Cirujanos , Humanos , Estudios de Cohortes , Hernia Inguinal/cirugía , Hernia Inguinal/etiología , Herniorrafia/efectos adversos , Herniorrafia/métodos , Hospitales , Laparoscopía/efectos adversos , Laparoscopía/métodos , Estudios Retrospectivos , Mallas Quirúrgicas/efectos adversos , Adolescente , Adulto
8.
Hernia ; 27(6): 1515-1524, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38007413

RESUMEN

PURPOSE: Inguinal hernia repair is one of the most common operations performed globally. Identification of risk factors that contribute to hernia recurrence following an index inguinal hernia repair, especially those that are modifiable, is of paramount importance. Therefore, we sought to investigate risk factors for reoperation following index inguinal hernia repair. METHODS: 125,133 patients aged ≥ 18 years who underwent their first inguinal hernia repair with mesh within a large US integrated healthcare system were identified for a cohort study (2010-2020). Laparoscopic, robotic, and open procedures were included. The system's integrated electronic health record was used to obtain data on demographics, patient characteristics, surgical characteristics, and reoperations. The association of these characteristics with ipsilateral reoperation during follow-up was modeled using Cox proportional-hazards regression. Risk factors were selected into the final model by stepwise regression with Akaike Information Criteria, which quantifies the amount of information lost if a factor is left out of the model. Factors associated with reoperation with p < 0.05 were considered statistically significant. RESULTS: The cumulative incidence of reoperation at 5-year follow-up was 2.4% (95% CI 2.3-2.5). Increasing age, female gender, increasing body mass index, White race, chronic pulmonary disease, diabetes, drug abuse, peripheral vascular disease, and bilateral procedures all associated with a higher risk for reoperation during follow-up. CONCLUSION: This study identifies several risk factors associated with reoperation following inguinal hernia repair. These risk factors may serve as targets for optimization protocols prior to elective inguinal hernia repair, with the goal of reducing reoperation risk.


Asunto(s)
Prestación Integrada de Atención de Salud , Hernia Inguinal , Laparoscopía , Humanos , Femenino , Reoperación , Hernia Inguinal/cirugía , Hernia Inguinal/etiología , Estudios de Cohortes , Herniorrafia/efectos adversos , Herniorrafia/métodos , Recurrencia , Factores de Riesgo , Laparoscopía/métodos , Mallas Quirúrgicas/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía
9.
J Virol ; 85(18): 9385-94, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21752909

RESUMEN

Targeting dendritic cells (DC) is key to driving effective immune responses. Lymphatic cannulation provides access to the heterogeneous populations of DC draining peripheral sites in rodents and ruminants. Afferent lymph DEC-205(+) CD11c(+) SIRPα(+) DC were preferentially infected ex vivo with three vaccine viral vectors: recombinant human replication-defective human adenovirus 5 (rhuAdV5), recombinant modified vaccinia virus Ankara (rMVA), and recombinant fowlpox virus (rFPV), all expressing green fluorescent protein (GFP). The rhuAdV5-infected cells remained viable, and peak GFP expression was observed 16 to 24 h posttransduction. Increasing the incubation period of DC with rhuAdV5 enhanced GFP expression. In contrast, DC infected with rMVA-GFP or rFPV-GFP became rapidly apoptotic and GFP expression peaked at 6 h postinfection. Delivery of foot-and-mouth disease virus (FMDV) A(22) antigen to DC by rhuAdV5-FMDV-A(22) ex vivo resulted in significantly greater CD4(+) T cell proliferation than did delivery by rFPV-FMDV-A(22). Delivery of rhuAdV5-GFP in oil adjuvant in vivo, to enhance DC-vector contact, resulted in increased GFP expression in migrating DC compared to that with vector alone. Similarly, CD4(+) T cell responses were significantly enhanced when using rhuAdV5-FMDV-A(22) in adjuvant. Therefore, the interaction between viral vectors and afferent lymph DC ex vivo can predict the outcome of in vivo immunization and provide a means of rapidly assessing the effects of vector modification.


Asunto(s)
Adenovirus Humanos/inmunología , Células Dendríticas/inmunología , Células Dendríticas/virología , Virus de la Viruela de las Aves de Corral/inmunología , Virus Vaccinia/inmunología , Vacunas Virales/inmunología , Adenovirus Humanos/genética , Adenovirus Humanos/patogenicidad , Animales , Antígenos Virales/genética , Antígenos Virales/inmunología , Linfocitos T CD4-Positivos/inmunología , Bovinos , Proliferación Celular , Supervivencia Celular , Virus de la Fiebre Aftosa/genética , Virus de la Fiebre Aftosa/inmunología , Virus de la Viruela de las Aves de Corral/patogenicidad , Ganglios Linfáticos/citología , Ganglios Linfáticos/inmunología , Vacunación/métodos , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Virus Vaccinia/patogenicidad , Vacunas Virales/administración & dosificación , Vacunas Virales/genética
10.
Cytotherapy ; 13(5): 618-28, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21171821

RESUMEN

BACKGROUND AIMS: Immunotherapy targeting MAGE-A3 in multiple myeloma (MM) could eradicate highly aggressive and proliferative clonal cell populations responsible for relapse. However, expression of many cancer-testis antigens, including MAGE-A3, can be heterogeneous, leading to the potential for tumor escape despite MAGE-A3-induced immunity. We hypothesized that a combination of the hypomethylating agent 5-azacitidine (5AC) and the histone deacetylase inhibitor (HDACi) MGCD0103 (MGC) could induce MAGE-A3 expression in MAGE-A3-negative MM, resulting in recognition and killing of MM cells by MAGE-A3-specific cytotoxic T lymphocytes (CTL). METHODS: Gene expression analyses of MAGE-A3 expression in primary MM patient samples at diagnosis and relapse were completed to identify populations that would benefit from MAGE-A3 immunotherapy. MM cell lines were treated with 5AC and MGC. Real-time polymerase chain reaction (PCR) and Western blotting were performed to assess MAGE-A3 RNA and protein levels, respectively. Chromium-release assays and interferon (IFN) secretion assays were employed to ascertain MAGE-A3 CTL specificity against treated targets. RESULTS: Gene expression analysis revealed that MAGE-A3 is expressed in MM patients at diagnosis (25%) and at relapse (49%). We observed de novo expression of MAGE-A3 RNA and protein in MAGE-A3-negative cell lines treated with 5AC. MGC treatment alone did not induce expression but sequential 5AC/MGC treatment led to enhanced expression and augmented recognition by MAGE-A3-specific CTL, as assessed by (51)Cr-release assays (P = 0.047) and enzyme-linked immunosorbent assay (ELISA) for IFN-γ secretion (P = 0.004). CONCLUSIONS: MAGE-A3 is an attractive target for immunotherapy of MM and epigenetic modulation by 5AC, and MGC can induce MAGE-A3 expression and facilitate killing by MAGE-A3-specific CTL.


Asunto(s)
Antígenos de Neoplasias/genética , Protocolos de Quimioterapia Combinada Antineoplásica , Azacitidina/uso terapéutico , Benzamidas/uso terapéutico , Epigénesis Genética/efectos de los fármacos , Inhibidores de Histona Desacetilasas/uso terapéutico , Mieloma Múltiple/terapia , Proteínas de Neoplasias/genética , Pirimidinas/uso terapéutico , Linfocitos T Citotóxicos/trasplante , Antígenos de Neoplasias/inmunología , Línea Celular Tumoral , Metilación de ADN/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Mieloma Múltiple/genética , Mieloma Múltiple/inmunología , Proteínas de Neoplasias/inmunología , Prevención Secundaria , Linfocitos T Citotóxicos/inmunología
11.
Clin Med (Lond) ; 10(5): 464-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21117378

RESUMEN

Pressure on working hours has led to a decrease in opportunities for training in invasive medical procedures for junior doctors. The effect of a structured course on immediate and medium-term changes in self-reported confidence was investigated. A one-day model-based practical course was run on two separate occasions teaching central venous line placement, lumbar puncture, Seldinger-technique chest drain insertion and knee joint aspiration. Attendees were asked to indicate their confidence in each procedure on a 10-point Likert scale before, immediately after and three months after the course. Significant improvements in self-reported confidence were seen for all procedures which were sustained at three months. Feedback was universally positive. Practical preclinical training may be a useful adjunct to patient-based training in invasive procedures. The course was particularly popular with foundation year trainees: ideally this training should be available before trainees' first exposure in the clinical setting.


Asunto(s)
Competencia Clínica , Educación de Postgrado en Medicina/métodos , Internado y Residencia , Enseñanza/métodos , Análisis de Varianza , Cateterismo Venoso Central/métodos , Tubos Torácicos , Humanos , Punción Espinal/métodos , Succión/educación , Succión/métodos , Encuestas y Cuestionarios
12.
Biochem Biophys Res Commun ; 366(3): 775-8, 2008 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-18083115

RESUMEN

Reactive oxygen species (ROS) are critical in tissue responses to ischemia-reperfusion. The enzyme methionine sulfoxide reductase-A (MsrA) is capable of protecting cells against oxidative damage by reversing damage to proteins caused by methionine oxidation or by decreasing ROS through a scavenger mechanism. The current study employed adenovirus mediated over-expression of MsrA in primary neonatal rat cardiac myocytes to determine the effect of this enzyme in protecting against hypoxia/reoxygenation in this tissue. Cells were transduced with MsrA encoding adenovirus and subjected to hypoxia/reoxygenation. Apoptotic cell death was decreased by greater than 45% in cells over-expressing MsrA relative to cells transduced with a control virus. Likewise total cell death as determined by levels of LDH release was dramatically decreased by MsrA over-expression. These observations indicate that MsrA is protective against hypoxia/reoxygenation stress in cardiac myocytes and point to MsrA as an important therapeutic target for ischemic heart disease.


Asunto(s)
Cardiotónicos/metabolismo , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Oxidorreductasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Animales , Animales Recién Nacidos , Apoptosis , Hipoxia de la Célula , Células Cultivadas , Ratas
13.
J Evol Biol ; 21(5): 1408-17, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18544070

RESUMEN

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species--the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener.


Asunto(s)
Germinación , Hibridación Genética , Semillas/crecimiento & desarrollo , Silene/fisiología , Análisis de Varianza , Cruzamientos Genéticos , Flores/fisiología , Razón de Masculinidad , Factores de Tiempo
14.
Mol Cell Biol ; 13(2): 749-61, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8423799

RESUMEN

Schizosaccharomyces pombe is becoming an increasingly useful organism for the study of cellular processes, since in certain respects, such as the cell cycle and splicing, it is similar to metazoans. Previous biochemical studies have shown that the DNA binding ability of S. pombe heat shock factor (HSF) is fully induced only under stressed conditions, in a manner similar to that of Drosophila melanogaster and humans but differing from the constitutive binding by HSF in the budding yeasts. We report the isolation of the cDNA and gene for the HSF from S. pombe. S. pombe HSF has a domain structure that is more closely related to the structure of human and D. melanogaster HSFs than to the structure of the budding yeast HSFs, further arguing that regulation of HSF in S. pombe is likely to reflect regulation in metazoans. Surprisingly, the S. pombe HSF gene is required for growth at normal temperatures. We show that the S. pombe HSF gene can be replaced by the D. melanogaster HSF gene and that strains containing either of these genes behave similarly to transiently heat-shocked strains with respect to viability and the level of heat-induced transcripts from heat shock promoters. Strains containing the D. melanogaster HSF gene, however, have lower growth rates and show altered morphology at normal growth temperatures. These data demonstrate the functional conservation of domains of HSF that are required for response to heat shock. They further suggest a general role for HSF in growth of eukaryotic cells under normal (nonstressed) growth conditions.


Asunto(s)
Proteínas Fúngicas/metabolismo , Proteínas de Choque Térmico/metabolismo , Schizosaccharomyces/crecimiento & desarrollo , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN de Hongos/metabolismo , Drosophila melanogaster/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Proteínas de Choque Térmico/genética , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Unión Proteica , Schizosaccharomyces/genética , Homología de Secuencia de Aminoácido , Temperatura , Factores de Transcripción/genética
15.
Mol Cell Biol ; 13(11): 6752-65, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8413270

RESUMEN

The cardiac troponin C (cTnC) gene produces identical transcripts in slow-twitch skeletal muscle and in heart muscle (R. Gahlmann, R. Wade, P. Gunning, and L. Kedes, J. Mol. Biol. 201:379-391, 1988). A separate gene encodes the fast-twitch skeletal muscle troponin C and is not expressed in heart muscle. We have used transient transfection to characterize the regulatory elements responsible for skeletal and cardiac cell-type-specific expression of the human cTnC (HcTnC) gene. At least four separate elements cooperate to confer tissue-specific expression of this gene in differentiated myotubes; a basal promoter (between -61 and -13) augments transcription 9-fold, upstream major regulatory sequences (between -68 and -142 and between -1319 and -4500) augment transcription as much as 39-fold, and at least two enhancer-like elements in the first intron (between +58 and +1028 and between +1029 and +1523) independently augment transcription 4- to 5-fold. These enhancers in the first intron increase myotube-specific chloramphenicol acetyltransferase activity when linked to their own promoter elements or to the heterologous simian virus 40 promoter, and the effects are multiplicative rather than additive. Each of the major myotube regulatory regions is capable of responding directly or indirectly to the myogenic determination factor, MyoD.A MyoD expression vector in 10T1/2 cells induced constructs carrying either the upstream HcTnC promoter elements or the first intron of the gene 300- to 500-fold. Expression was inhibited by cotransfection with Id, a negative regulator of basic helix-loop-helix transcription factors. The basal promoter contains five tandem TGGGC repeats that interact with Sp1 or an Sp1-like factor in nuclear extracts. Mutational analysis of this element demonstrated that two of the five repeat sequences were sufficient to support basal level muscle cell-specific transcription. Whereas the basal promoter is also critical for expression in cardiac myocytes, the elements upstream of -67 appear to play little or no role. Major augmentation of expression in cardiomyocytes is also provided by sequences in the first intron, but these are upstream (between +58 and +1028). The downstream segment of the first intron has no enhancer activity in cardiomyocytes. A specific DNA-protein complex is formed by this C2 cell enhancer with extracts from C2 cells but not cardiomyocytes. These observations suggest that tissue-specific expression of the HcTnC gene is cooperatively regulated by the complex interactions of multiple regulatory elements and that different elements are used to regulate expression in myogenic and cardiac cells.


Asunto(s)
Regulación de la Expresión Génica , Proteína MioD/metabolismo , Miocardio/metabolismo , Regiones Promotoras Genéticas , Troponina/biosíntesis , Troponina/genética , Animales , Animales Recién Nacidos , Secuencia de Bases , Células Cultivadas , Cloranfenicol O-Acetiltransferasa/biosíntesis , Secuencia Conservada , Cartilla de ADN , Elementos de Facilitación Genéticos , Humanos , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos , Ratas , Proteínas Recombinantes de Fusión/biosíntesis , Eliminación de Secuencia , Homología de Secuencia de Ácido Nucleico , Transfección , Troponina C
16.
Mol Cell Biol ; 7(10): 3646-55, 1987 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2824993

RESUMEN

The human heat shock protein 70 (hsp70) gene is expressed constitutively in a wide variety of cells. Two separate promoter domains determine this basal level of hsp70 expression. The proximal domain is contained within 84 bases of the transcription initiation site and consists of three elements which appear to interact with the TATA factor(s) and CCAAT-box-binding transcription factor and SP1, respectively. The proximal domain is sufficient for near-maximal basal expression to rodent cell lines. The distal promoter domain consists of sequences upstream of -84 and is necessary in conjunction with the proximal domain for full basal expression in human cell lines. Although in BALB/c 3T3 cells the distal promoter domain plays little role in basal expression, it is functional as evidenced by the ability to compensate efficiently for mutations in the proximal CCAATC homology. The distal domain does not compensate as efficiently for proximal-domain mutations in HeLa cells. Basal expression of this human hsp70 promoter is, therefore, determined by multiple elements. Fewer elements are required for basal expression in rodent cell lines than in human cell lines, suggesting that there are significant differences between the rodent and human transcription apparatuses.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Regulación de la Expresión Génica , Proteínas de Choque Térmico/genética , Regiones Promotoras Genéticas , Factores de Transcripción/fisiología , Animales , Línea Celular , Análisis Mutacional de ADN , Endonucleasas , Humanos , Metilación , Ratones , Ratas , Secuencias Reguladoras de Ácidos Nucleicos , Endonucleasas Específicas del ADN y ARN con un Solo Filamento , Especificidad de la Especie
17.
Clin Infect Dis ; 42(1): 51-6, 2006 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-16323091

RESUMEN

BACKGROUND: Invasive fungal infections due to less-common molds are an increasing problem, and accurate diagnosis is difficult. METHODS: We used our previously established molecular method, which allows species identification of molds in histological tissue sections, to test sequential specimens from 56 patients with invasive fungal infections who were treated at our institution from 1982 to 2000. RESULTS: The validity of the method was demonstrated with the establishment of a molecular diagnosis in 52 cases (93%). Confirmation of the causative organism was made in all cases in which a mold had been cultured from the tissue specimen. Less-common molds were identified in 7% of cases and appear to be an increasing problem. CONCLUSIONS: Our previously established method has proven to be of value in determining the incidence of invasive infection caused by less-common molds. Institutions should continue to pursue diagnosis of invasive fungal infections by means of tissue culture and microbiologic analysis.


Asunto(s)
Aspergilosis/diagnóstico , Aspergilosis/microbiología , Aspergillus flavus/aislamiento & purificación , Aspergillus fumigatus/aislamiento & purificación , Aspergillus flavus/genética , Aspergillus fumigatus/genética , Humanos , Técnicas de Diagnóstico Molecular
18.
Proc Biol Sci ; 273(1596): 1961-7, 2006 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-16822758

RESUMEN

Human cytomegalovirus can cause a diverse range of diseases in different immunocompromised hosts. The pathogenic mechanisms underlying these diseases have not been fully elucidated, though the maximal viral load during infection is strongly correlated with the disease. However, concentrating on single viral load measures during infection ignores valuable information contained during the entire replication history up to the onset of disease. We use a statistical model that allows all viral load data sampled during infection to be analysed, and have applied it to four immunocompromised groups exhibiting five distinct cytomegalovirus-related diseases. The results show that for all diseases, peaks in viral load contribute less to disease progression than phases of low virus load with equal amount of viral turnover. The model accurately predicted the time of disease onset for fever, gastrointestinal disease and pneumonitis but not for hepatitis and retinitis, implying that other factors may be involved in the pathology of these diseases.


Asunto(s)
Infecciones por Citomegalovirus/virología , Citomegalovirus/patogenicidad , Huésped Inmunocomprometido , Modelos Estadísticos , Replicación Viral , Citomegalovirus/fisiología , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/inmunología , Retinitis por Citomegalovirus/inmunología , Retinitis por Citomegalovirus/virología , Fiebre/inmunología , Fiebre/virología , Enfermedades Gastrointestinales/inmunología , Enfermedades Gastrointestinales/virología , Hepatitis/inmunología , Hepatitis/virología , Humanos , Neumonía/inmunología , Neumonía/virología , Carga Viral
19.
Bone Marrow Transplant ; 38(1): 47-51, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16715107

RESUMEN

This open-label, dose-escalation study assessed the maximum tolerated dose (MTD) of the new antifungal micafungin in patients undergoing haematopoietic stem cell transplantation (HSCT). Participants received 3, 4, 6 or 8 mg/kg/day micafungin intravenously from 7 days to a maximum of 28 days or until neutropaenia resolved. The MTD was defined as the highest dose not causing the same Grade 3 or 4 adverse event in three or more patients. All 36 participants received >/=8 days treatment for a median of 18 days (range: 8-28); 1 patient withdrew consent and a further 11 discontinued to receive another systemic antifungal agent for a suspected infection. No case of confirmed invasive fungal infection occurred. Adverse events were those expected for patients undergoing HSCT and showed no evidence of dose-related toxicity. Criteria for MTD were not met; no patient had a Grade 3 or 4 adverse event considered causally related to micafungin. Thus, the MTD of micafungin can be inferred to be 8 mg/kg/day or higher.


Asunto(s)
Antifúngicos/efectos adversos , Trasplante de Células Madre Hematopoyéticas , Lipoproteínas/efectos adversos , Péptidos Cíclicos/efectos adversos , Adulto , Antifúngicos/administración & dosificación , Esquema de Medicación , Equinocandinas , Femenino , Humanos , Infusiones Intravenosas , Lipopéptidos , Lipoproteínas/administración & dosificación , Masculino , Dosis Máxima Tolerada , Micafungina , Persona de Mediana Edad , Péptidos Cíclicos/administración & dosificación , Seguridad , Trasplante Autólogo , Trasplante Homólogo , Resultado del Tratamiento
20.
J Clin Oncol ; 9(10): 1840-7, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1919634

RESUMEN

The results in 34 adult patients with acute myeloid leukemia (AML) who have undergone autologous bone marrow transplantation (ABMT) using busulfan and cyclophosphamide (Bu/Cy) in 12 United Kingdom (UK) centers have been analyzed. There were 19 females and 15 males; median age was 40 years (range, 21 to 62 years). Nine patients were in first relapse; 25 were in second remission. The median time of first remission for the whole group was 11.5 months (range, 1 to 56 months). All the patients in first relapse and six patients in second remission received first remission marrow. The leukemia-free survival (LFS) for the patients in first relapse was 33%, with a median follow-up of 20 months. The LFS for the patients in second remission was 48% with a median follow-up of 26 months. The length of second remission exceeds the length of first remission in 14 patients. Considerable toxicity with hemorrhagic cystitis (four patients; none fatal), venoocclusive disease (four patients; one fatal), pneumonitis (four patients; one fatal), intracranial hemorrhage (two patients; two fatal) has occurred. There have been four procedure-related deaths (12%). Hematologic recovery was satisfactory for neutrophils (median time to 0.5 x 10(9)/L, 22 days [range, 11 to 101 days]), but very slow for platelets (median time to 50 x 10(9)/L, 62 days [range, 15 to 1,080 days]). This study suggests that the use of Bu/Cy with ABMT for patients beyond first remission in AML compares favorably with chemotherapy, and although the procedure-related mortality is acceptable, it is associated with protracted platelet recovery.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Médula Ósea/métodos , Leucemia Mieloide/terapia , Enfermedad Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Trasplante de Médula Ósea/efectos adversos , Busulfano/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inducción de Remisión , Análisis de Supervivencia , Trasplante Autólogo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA