Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 339
Filtrar
1.
BJA Educ ; 23(2): 42-45, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36686886
2.
Heredity (Edinb) ; 115(2): 115-24, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23963342

RESUMEN

Habitat fragmentation is extensive throughout the world, converting natural ecosystems into fragments of varying size, density and connectivity. The potential value of remnant trees in agricultural landscapes as seed sources and in connecting fragments has formed a fertile area of debate. This study contrasted the mating patterns of bat-pollinated Pachira quinata trees in a continuous forest to those in pasture through microsatellite-based paternity analysis of progeny. The breeding system was determined by analysis of pollen tube growth and seed production from controlled pollinations. Fitness of selfed and outcrossed seed was compared by germination and seedling growth. There was more inbreeding within pasture trees (outcrossing=0.828±0.015) compared with forest trees (0.926±0.005). Pasture trees had fewer sires contributing to mating events, but pollen dispersal distances were greater than those in the forest. Paternity analysis showed variation in outcrossing rates among pasture trees with high proportions of external and self pollen sources detected. A leaky self-incompatibility system was found, with self pollen having reduced germination on stigmas and slower growth rate through the style. Controlled pollinations also showed a varied ability to self among trees, which was reflected in the selfing rates among pasture trees shown by the paternity analysis (0-80% selfing). Self pollination resulted in lower seed set, germination and seedling growth compared with outcrossing. While remnant trees in agricultural landscapes are involved in broader mating patterns, they show increased but varied levels of inbreeding, which result in reduced fitness.


Asunto(s)
Genética de Población , Endogamia , Malvaceae/genética , Autoincompatibilidad en las Plantas con Flores , Árboles/genética , Costa Rica , ADN de Plantas/genética , Bosques , Aptitud Genética , Variación Genética , Genotipo , Repeticiones de Microsatélite , Polen/genética , Reproducción/genética , Semillas/genética , Autofecundación , Análisis de Secuencia de ADN
3.
Eur J Pediatr Surg ; 20(2): 73-7, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19882502

RESUMEN

INTRODUCTION: The laparoscopic treatment of pediatric populations remains controversial. This review was conducted to compare the clinical and cost effectiveness of laparoscopic and open surgical approaches for a variety of surgical indications in pediatric populations. METHOD/DESIGN: A computerized comprehensive search supplemented by a manual review of the literature was performed for all peer-reviewed publications comparing laparoscopic and open appendectomy, fundoplication and hernia repair cohorts. Outcomes of interest were length of stay (LOS), operating room (OR) time, complication rates and total hospital costs; aggregation of outcome rates was performed with the Mantel-Haenszel method. RESULTS: A total of 24 articles were identified that met the search and inclusion criteria. LOS was found to be significantly reduced in favor of the laparoscopic approach, with a weighted mean difference of -1.44 days, although the OR time was significantly increased, with a weighted mean difference of +12.8 min. Laparoscopic intervention was associated with a significantly reduced complication rate compared to the open approach (10.6 vs. 15.6%). Total hospital costs of the laparoscopic approaches were found to be insignificantly increased compared to the open techniques. CONCLUSION: This review further supports the use of minimally invasive surgery (MIS) in pediatric populations, demonstrating that the three types laparoscopic procedures reviewed resulted in better patient outcomes compared to open procedures, in the form of reduced LOS and overall complication rates. Increased utilization of this approach may prove beneficial to pediatric patients.


Asunto(s)
Laparoscopía , Humanos , Laparoscopía/economía , Laparoscopía/métodos , Resultado del Tratamiento
4.
Am J Transplant ; 6(1): 150-60, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16433769

RESUMEN

Rejection diagnosis by endomyocardial biopsy (EMB) is invasive, expensive and variable. We investigated gene expression profiling of peripheral blood mononuclear cells (PBMC) to discriminate ISHLT grade 0 rejection (quiescence) from moderate/severe rejection (ISHLT > or = 3A). Patients were followed prospectively with blood sampling at post-transplant visits. Biopsies were graded by ISHLT criteria locally and by three independent pathologists blinded to clinical data. Known alloimmune pathways and leukocyte microarrays identified 252 candidate genes for which real-time PCR assays were developed. An 11 gene real-time PCR test was derived from a training set (n = 145 samples, 107 patients) using linear discriminant analysis (LDA), converted into a score (0-40), and validated prospectively in an independent set (n = 63 samples, 63 patients). The test distinguished biopsy-defined moderate/severe rejection from quiescence (p = 0.0018) in the validation set, and had agreement of 84% (95% CI 66% C94%) with grade ISHLT > or = 3A rejection. Patients >1 year post-transplant with scores below 30 (approximately 68% of the study population) are very unlikely to have grade > or = 3A rejection (NPV = 99.6%). Gene expression testing can detect absence of moderate/severe rejection, thus avoiding biopsy in certain clinical settings. Additional clinical experience is needed to establish the role of molecular testing for clinical event prediction and immunosuppression management.


Asunto(s)
Perfilación de la Expresión Génica , Rechazo de Injerto/diagnóstico , Trasplante de Corazón , Adolescente , Adulto , Anciano , Femenino , Rechazo de Injerto/genética , Rechazo de Injerto/patología , Trasplante de Corazón/inmunología , Humanos , Terapia de Inmunosupresión , Leucocitos Mononucleares/química , Masculino , Persona de Mediana Edad , ARN Mensajero/análisis
5.
Genes Immun ; 5(6): 451-60, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15190266

RESUMEN

The interleukin-1 gene cluster is a key regulator in a number of chronic disease processes. We explored the linkage between nine polymorphic loci in the IL1R1 promoter, eight in the IL1A-IL1B-IL1RN gene complex, and their association with osteoarthritis (OA), a common complex disease associated with low-level inflammation. Using 195 healthy controls, we identified eight novel polymorphisms in the IL1R1 exon 1A region. We found limited LD between IL1R1 and the IL1A-IL1B-IL1RN cluster, although LD within these two individual groups was high. To test association with knee OA, we genotyped 141 patients from Bristol (UK) at the 17 loci. IL1R1 promoter haplotypes showed no association with disease. However, within the IL1A-IL1B-IL1RN complex, we identified a common haplotype conferring a four-fold risk of OA (P=0.00043; Pc=0.0043) and one IL1B-IL1RN haplotype conferring a four-fold reduced risk (P=0.0036; Pc=0.029). To replicate these associations, we subsequently examined 163 knee OA patients from London. Here, the effects of the haplotypes were confirmed: the risk IL1A-IL1B-IL1RN haplotype conferred a two-fold risk of OA (P=0.02), and the protective IL1B-IL1RN haplotype conferred a five-fold reduced risk of OA (P=0.0000008). These results may help to explain the genome-wide scan linkage data and functional observations concerning association between IL-1 and OA.


Asunto(s)
Interleucina-1/genética , Desequilibrio de Ligamiento , Osteoartritis de la Rodilla/genética , Polimorfismo de Nucleótido Simple/genética , Receptores de Interleucina-1/genética , Sialoglicoproteínas/genética , Anciano , Secuencia de Bases , Estudios de Casos y Controles , Femenino , Genotipo , Haplotipos/genética , Humanos , Proteína Antagonista del Receptor de Interleucina 1 , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Familia de Multigenes , Regiones Promotoras Genéticas/genética , Receptores de Interleucina-1/antagonistas & inhibidores , Receptores Tipo I de Interleucina-1 , Factores de Riesgo , Homología de Secuencia de Ácido Nucleico , Secuencias Repetidas en Tándem/genética
6.
Circulation ; 104(21): 2615-9, 2001 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-11714659

RESUMEN

BACKGROUND: Allograft coronary atherosclerosis (TxCAD) is the leading cause of death after the first year after transplantation. TxCAD is believed to be a form of chronic rejection of the cardiac allografts. This study was undertaken to determine whether TxCAD could develop in the absence of a cellular alloimmune response. METHODS AND RESULTS: Inbred lean Zucker rats (>26 generations) served as donors and recipients of the cardiac grafts. Donor hearts were explanted at 60 or 90 days. Explanted hearts were processed for coronary artery histological analysis. Cytokine expression was determined by reverse transcription-polymerase chain reaction, and the presence of T cells within the explanted hearts was evaluated by immunohistochemistry. Forty-six transplantations were made, and TxCAD developed in all but one of the transplanted hearts. Overall, one third of the vessels examined were affected by TxCAD, and in roughly half of these vessels, the disease was severe. Native hearts were free of atherosclerosis. Interleukin-2 was absent from the transplanted hearts, and T cells were present in minimal amounts (<1 per low-power field). CONCLUSIONS: TxCAD developed in the absence of a cellular alloimmune response in these genetically similar donors and recipients. The observed TxCAD was significant and comparable to what is found in rat allografting models.


Asunto(s)
Enfermedad de la Arteria Coronaria/etiología , Modelos Animales de Enfermedad , Trasplante de Corazón/efectos adversos , Animales , Glucemia/metabolismo , Enfermedad de la Arteria Coronaria/metabolismo , Enfermedad de la Arteria Coronaria/patología , Citocinas/biosíntesis , Citocinas/genética , Citocinas/inmunología , Femenino , Inmunohistoquímica , Lípidos/sangre , Masculino , ARN Mensajero/biosíntesis , Ratas , Ratas Zucker , Linfocitos T/inmunología , Tolerancia al Trasplante
9.
Transplantation ; 70(7): 1038-49, 2000 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11045640

RESUMEN

BACKGROUND: Assays of drug blood levels are used for therapeutic immunosuppressive drug monitoring (pharmacokinetics, PK). We monitored lymphocyte functions (pharmacodynamics, PD) in allograft recipients treated with mycophenolic acid (MPA) to determine its mechanisms and the relationships among dose levels, PK, PD, and histological severity of graft rejection. METHODS: Lewis rats transplanted with Brown Norway (BN) rat hearts were treated with different dose levels of MPA for 8, 15, or 29 days at which times grafts were removed and scored for rejection grade. Blood was analyzed (high-performance liquid chromatography) for MPA plasma concentrations (area under the concentration-time curve0-24 hr, C6 hr, trough) and for lymphocyte functions using concanavalin A-stimulated whole blood assays to measure lymphocyte proliferation (tritium labeled thymidine incorporation and flow cytometric bivariate proliferating nuclear cell antigen/DNA analysis) and activation (percent lymphocytes expressing CD25 or CD134). PD values were AUE0-24 hr (area under the PD effect-time curve), maximum inhibition and trough. RESULTS: MPA equipotently suppressed (by flow cytometry) both proliferation and activation and these effects correlated with MPA plasma levels (r2=0.80-0.91). Relationships among MPA dose levels, PK and PD were clear, direct, and reproducible. Correlation coefficients after 8 days of MPA treatment were: 0.90, 0.87, and 0.49 for MPA PK (AUC0-24 hr, C6 hr and trough) versus rejection scores; 0.80-0.89, 0.86-0.92, and 0.25-0.52 for PD flow cytometric assays (AUE0-24 hr, maximum inhibition, and trough) versus rejection scores. CONCLUSIONS: MPA inhibits both lymphocyte proliferation and activation. PD by flow cytometry (FCM) correlates highly with severity of graft rejection, showing that PD of MPA measured in peripheral blood predicts immune cell activity in graft tissue.


Asunto(s)
Ácido Micofenólico/farmacología , Receptores del Factor de Necrosis Tumoral , Animales , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/inmunología , Trasplante de Corazón/inmunología , Trasplante de Corazón/patología , Trasplante de Corazón/fisiología , Activación de Linfocitos/efectos de los fármacos , Masculino , Ácido Micofenólico/administración & dosificación , Ácido Micofenólico/farmacocinética , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Receptores de Interleucina-2/biosíntesis , Receptores de Interleucina-2/efectos de los fármacos , Receptores OX40 , Índice de Severidad de la Enfermedad , Trasplante Homólogo/fisiología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/biosíntesis , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/efectos de los fármacos
10.
Transplantation ; 70(3): 420-9, 2000 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-10949182

RESUMEN

BACKGROUND: Graft vascular disease (GVD) is an incompletely understood process and the primary cause of late allograft failure. A nonhuman primate model was established to study the progression of GVD by using serial intravascular ultrasound (IVUS). METHODS: Aortic allografts were transplanted below the inferior mesenteric arteries (IMA) into 6 rhesus monkeys. Removed and re-implanted aortic segments between renal arteries, and the inferior mesenteric arteries served as autografts. IVUS was performed at days 0, 24, 52, 80, and 98 after transplantation. Vessel area (VA) and lumen area (LA) were measured from each cross-section at 0.5 mm intervals. Intimal index (II=100x (VA-LA/VA)) and corresponding vessel volumes were calculated for the whole grafts. Histologic features were assessed from autopsy samples using computerized morphometric method and a score from 0 to 3 for GVD (0=none, 3=severe). RESULTS: In allografts, vessel volume and luminal volume decreased significantly (P<0.05 for both) and the intimal index increased from 12% to 59% by day 98. These parameters remained unchanged in autografts. Histologic analysis of allografts showed concentric intimal hyperplasia and scattered mononuclear cell accumulations, whereas the autografts had only occasional eccentric intimal changes. The GVD-scores were significantly higher in allografts than in autografts (median 3 vs. 1, P=0.042). CONCLUSIONS: We introduce a nonhuman primate model of GVD that enables serial IVUS assessments of multiple parameters of GVD. Concentric intimal proliferation and decrease of vessel dimensions was observed in allografts as a consequence of alloimmunity. This is a potential new model for studying new therapies to prevent GVD or halt its progression.


Asunto(s)
Aorta/trasplante , Rechazo de Injerto/diagnóstico por imagen , Enfermedades Vasculares/diagnóstico por imagen , Animales , Aorta/diagnóstico por imagen , Aorta/patología , Modelos Animales de Enfermedad , Rechazo de Injerto/inmunología , Rechazo de Injerto/patología , Hiperplasia , Isoanticuerpos/sangre , Macaca mulatta , Factores de Tiempo , Trasplante Autólogo , Trasplante Homólogo , Ultrasonografía , Enfermedades Vasculares/inmunología , Enfermedades Vasculares/patología
11.
J Endocrinol ; 165(3): 545-56, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10828838

RESUMEN

Increased concentrations of insulin-like growth factor (IGF) system components have previously been observed in rheumatoid arthritis (RA) and osteoarthritis (OA); however, disruption of the IGF axis and the implications for the disease process remain largely unaddressed. This study was undertaken to characterise the IGF binding protein (IGFBP)-3 proteolysis and complex formation systems in synovial fluid and to investigate changes in these systems in arthritic disease, and their impact on the availability of IGF. Western blotting or autoradiography of SDS gels was used to visualise IGFBP-3 or its proteolysis. IGF-I and IGFBP-3 concentrations were determined by radioimmunoassays and acid-labile subunit (ALS) was measured by ELISA. A shift in distribution of IGFBP-3 and IGF-I in RA and OA synovial fluids (RASynF, OASynF) and an associated increase in ALS suggested the presence of 150 kDa ternary complexes. IGFBP-3 proteolysis was decreased in RASynF and OASynF, but was apparent in size-fractionated fluid and resembled serum activity. The presence of serum-like inhibitors of IGFBP-3 proteolysis in RASynF was also demonstrated by the ability of this fluid, and 150 kDa fractions from its size fractionation, to inhibit IGFBP-3 proteolysis in the other synovial fluid. A marked disruption in the IGF system was observed, as considerably more IGF-I was retained in ternary complexes. We also classified the IGFBP-3 proteolysis system in synovial fluid and found it to be disturbed in RASynF and OASynF. These changes may be caused by an increased flux of circulatory proteins into synovial fluid, resulting from an inflammation-induced increase in vascular permeability. The net result in RA and OA would be a decrease in IGF availability in arthritic joints, and therefore loss of a potential anabolic stimulus. This disruption to the IGF axis would influence disease progression in RA and OA.


Asunto(s)
Artritis Reumatoide/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Osteoartritis de la Rodilla/metabolismo , Líquido Sinovial/metabolismo , Adulto , Anciano , Artritis Reumatoide/sangre , Western Blotting , Electroforesis en Gel de Poliacrilamida , Endopeptidasas/sangre , Endopeptidasas/metabolismo , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Persona de Mediana Edad , Osteoartritis de la Rodilla/sangre , Embarazo
12.
Arthritis Rheum ; 43(6): 1226-32, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10857781

RESUMEN

OBJECTIVE: To study the expression of messenger RNA (mRNA) for different membrane-type matrix metalloproteinases (MT-MMPs) and compare their expression pattern in rheumatoid arthritis (RA) and normal synovium. METHODS: Polymerase chain reaction (PCR) with specific primers was performed to analyze the presence of MT1-, MT2-, MT3-, and MT4-MMP in synovial tissue and synovial fibroblasts from 10 patients with RA and 4 subjects without arthritis. In addition, in situ hybridization with digoxigenin-labeled RNA probes was used to investigate the expression pattern of MT-MMPs in the synovium of these subjects. MT-MMP-expressing cells were characterized by immunohistochemical double labeling with anti-CD68 monoclonal antibodies. RESULTS: Reverse transcription-PCR revealed the expression of MT1-, MT2-, MT3-, and MT4-MMP mRNA in all tissues and cell cultures examined. However, in situ hybridization showed considerable differences in the expression pattern of the different MT-MMPs in RA synovium. MT1- and MT3-MMP mRNA were highly expressed in both the lining and the sublining layer, with more intense staining in the lining. Immunohistochemical double labeling demonstrated the presence of mRNA for MT1-MMP in fibroblasts and macrophages, as well as in osteoclast-like cells at sites of bone resorption. Expression of MT3-MMP mRNA was seen in fibroblasts and some macrophages. Expression of MT2- and MT4-MMP was characterized by staining of only a few CD68-negative fibroblasts, and no differences could be found between the lining and sublining. Normal synovial samples showed only limited staining for all MT-MMPs. CONCLUSION: Our results indicate a role for MT1-MMP not only in the matrix degradation by fibroblasts, but also in osteoclast-mediated bone resorption in RA. Given the ability of MT1-MMP to activate MMP-2 and MMP-13, the findings also point to a cooperation between fibroblasts and macrophages in degrading cartilage and bone. While MT3-MMP is also intensely expressed in RA synovium, MT2- and MT4-MMP appear not to be involved in rheumatoid joint destruction.


Asunto(s)
Artritis Reumatoide/enzimología , Metaloproteinasas de la Matriz/metabolismo , Artritis Reumatoide/metabolismo , Humanos , Inmunohistoquímica , Hibridación in Situ , Metaloproteinasas de la Matriz/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/metabolismo , Valores de Referencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Membrana Sinovial/metabolismo
13.
Arthritis Rheum ; 43(12): 2634-47, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11145021

RESUMEN

OBJECTIVE: Rheumatoid arthritis (RA) is characterized by a progressive destruction of joints by invasive synovial fibroblasts (SF). We searched for retroviral sequences in RA synovial fluid pellets, identified a sequence similar to that of open reading frame 2 (ORF2)/L1 retrotransposable elements, explored the expression of L1 in RA synovial tissues and cultured RA SF, and investigated the link to genomic DNA hypomethylation and the influence of functional L1 on gene expression. METHODS: RA synovial fluid pellets were screened by reverse transcriptase-polymerase chain reaction (RT-PCR) using degenerated pol primers. The sequences were identified by GenBank search. Riboprobes to ORF2/L1 and galectin-3 and antibodies to the ORF1/L1-related p40 protein were used for in situ hybridization and immunohistochemistry of synovial tissues and cultured RA SF. Real-time quantitative RT-PCR was used for detecting ORF1 messenger RNA (mRNA). Since DNA hypomethylation occurs in inflammatory diseases, we incubated cells with the methylation inhibitor 5-aza-2'-deoxycytidine (5-azaC) and compared RA SF and osteoarthritis (OA) SF. L1-negative RA SF were transfected with the functional L1.2 construct, and differential gene expression was analyzed by subtractive hybridization combined with nested PCR. RESULTS: RNA sequences similar to those of ORF2/L1 retrotransposable elements, THE1 transposon, human endogenous retrovirus (ERV)-E, human ERV-HC2, and gibbon ape leukemia virus pol genes were isolated from different RA synovial fluid pellets. In RA synovial tissues, ORF2/L1 transcripts were detected in the sublining layer and at sites of cartilage and bone destruction. Galectin-3 mRNA and L1-related ORF1/ p40 protein showed similar expression patterns. In contrast, OA synovial tissues in situ and cultures in vitro were negative. Real-time quantitative RT-PCR confirmed the presence of ORF1 mRNA in cultured RA SF (30-300-fold the amount in normal SF), demonstrating the existence of a nondegenerated and functional L1 element. In vitro, the majority of RA SF expressed ORF2/L1 mRNA. After incubation of SF with 5-azaC, L1 mRNA appeared in a time- and dose-dependent manner. Compared with OA SF, RA SF were more sensitive to 5-azaC. After transfection of RA SF with a functional L1.2 element, human stress-activated protein kinase 2 delta (SAPK2delta [or SAPK4]), met protooncogene, and galectin-3 binding protein genes were differentially expressed. The transcription of the SAPK2delta gene, favored also by DNA hypomethylation in vitro, was confirmed in RA synovial tissues. CONCLUSION: Taken together, these data suggest that L1 elements and SAPK2delta pathways play a role in the activation of RA SF.


Asunto(s)
Artritis Reumatoide/genética , Elementos de Nucleótido Esparcido Largo/genética , Retroelementos/genética , Membrana Sinovial/metabolismo , Antígenos de Diferenciación/genética , Ectima Contagioso/genética , Fibroblastos/química , Galectina 3 , Expresión Génica , Humanos , Lectinas/genética , Elementos de Nucleótido Esparcido Largo/fisiología , Macrófagos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/genética , ARN Mensajero/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos
15.
Circulation ; 100(1): 67-74, 1999 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-10393683

RESUMEN

BACKGROUND: Chronic graft vascular disease (CGVD) in cardiac allografts has been defined as a slowly evolving vasculopathy unresponsive to conventional immunosuppression. We compared 4 rodent models of CGVD to evaluate the reproducibility of CGVD in heart allografts. Rapamycin (Rapa) and cyclosporine (CSA) were then used to treat CGVD. METHODS AND RESULTS: Hearts were harvested and placed heterotopically into allogenic recipients. CGVD scores of PVG allografts from ACI recipients treated with CSA on days 1 through 10 were significantly elevated on day 90 (n=16) compared with other models (immunosuppression used): (1) Lewis to F344 recipients (CSA), (2) Brown Norway to Lewis (FK506), and (3) DA to Wistar-Firth (methylprednisolone, azathioprine, CSA). Although delayed (day 60 to 90) CSA treatment had no effect (n=6), delayed Rapa (3 mg. kg-1. d-1 IP) reversed CGVD in PVG grafts (0.22+/-0.19 on day 90, n=6). ACI isografts showed no evidence of CGVD (n=6) at day 90. Immunohistochemistry of PVG grafts revealed perivascular infiltrates consisting of CD4(+) T cells and limited numbers of macrophages persisting up to day 90. Flow cytometry demonstrated increased levels of anti-donor antibody at day 90, which was significantly inhibited by Rapa treatment. CONCLUSIONS: PVG grafts developed a significant increase in CGVD without evidence of ongoing myocardial rejection. This CGVD appeared to be mediated by both cellular and humoral mechanisms, given CD4(+) perivascular infiltrates and increased levels of anti-donor antibody. The anti-CGVD effectiveness of Rapa during a period in which there was little myocardial cellular infiltrate supports a novel mechanism of effect such as smooth muscle or B-cell inhibition.


Asunto(s)
Enfermedad Coronaria/tratamiento farmacológico , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Trasplante de Corazón/efectos adversos , Inmunosupresores/uso terapéutico , Sirolimus/uso terapéutico , Animales , Formación de Anticuerpos/efectos de los fármacos , Especificidad de Anticuerpos , Enfermedad Coronaria/etiología , Enfermedad Coronaria/inmunología , Ciclosporina/uso terapéutico , Evaluación Preclínica de Medicamentos , Citometría de Flujo , Rechazo de Injerto , Enfermedad Injerto contra Huésped/etiología , Trasplante de Corazón/inmunología , Histocompatibilidad , Antígenos de Histocompatibilidad/inmunología , Inmunidad Celular/efectos de los fármacos , Inmunoglobulina G/sangre , Isoanticuerpos/sangre , Masculino , Óxido Nítrico/fisiología , Ratas , Ratas Endogámicas ACI , Ratas Endogámicas F344 , Ratas Endogámicas Lew , Ratas Endogámicas WF , Reproducibilidad de los Resultados , Trasplante Homólogo/efectos adversos , Trasplante Homólogo/inmunología
16.
Biochem Biophys Res Commun ; 258(3): 763-7, 1999 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10329460

RESUMEN

The initiating factors in primary, idiopathic osteoarthritis are unknown, the characteristic bone and cartilage changes being late features of the disease. We have proposed that biochemical cruciate ligament alteration may be important in early osteoarthritis by mediating loading consequences on the bone and cartilage. Using the widely accepted STR/ORT mouse model of spontaneous osteoarthritis we have found biochemical evidence that, before radiological signs of osteoarthritis develop, cruciate ligament collagen metabolism is upregulated in the STR/ORT mouse when compared to controls. Also, importantly, at this time the anterior cruciate ligament is weaker in STR/ORT mice than in controls. This is the first biochemical evidence to show that alterations in cruciate ligament metabolism occur early in the etiopathogenesis of idiopathic, primary osteoarthritis.


Asunto(s)
Ligamento Cruzado Anterior/metabolismo , Colágeno/metabolismo , Osteoartritis/metabolismo , Animales , Ligamento Cruzado Anterior/enzimología , Fenómenos Biomecánicos , Gelatinasas/metabolismo , Metaloproteinasa 2 de la Matriz , Metaloendopeptidasas/metabolismo , Ratones , Ratones Endogámicos CBA , Especificidad de la Especie
17.
J Rheumatol ; 26(1): 166-9, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9918259

RESUMEN

OBJECTIVE: To investigate the distribution pattern of membrane-type-1 matrix metalloproteinase (MT1-MMP) within the synovial-like interface membranes of failed prosthetic joints. METHODS: Interface tissue around loose arthroplasties containing both fibrous membrane and attached bone was obtained from 6 patients at revision surgery. In situ hybridization with digoxigenin labeled RNA probes was applied to investigate MT1-MMP expression in paraffin sections of the samples. In addition, double labeling using immunohistochemistry was performed to characterize MT1-MMP producing cells. RESULTS: Apart from being present in fibroblasts, MT1-MMP was also found expressed in osteoclasts at sites of bone resorption. Our results revealed no expression of MT1-MMP at parts of the membrane that originally had been located next to the prosthesis. In contrast, abundant staining for MT1-MMP was observed at sites attached to bone. MT1-MMP mRNA expression was more intense at those sites of bone resorption covered by a thicker interface membrane. CONCLUSION: These results indicate a role for MT1-MMP not only in matrix degradation by fibroblasts but also in osteoclast mediated bone resorption. Given the ability of MT1-MMP to activate MMP2 and MMP13, they suggest also that osteoclasts might contribute to matrix degradation by activating these MMP. This could be of potential interest not only for other conditions in which bone resorption by fibroproliferative tissue plays a role, but also to design novel strategies to prevent loosening of prosthetic joints.


Asunto(s)
Artroplastia de Reemplazo/efectos adversos , Fibroblastos/enzimología , Metaloendopeptidasas/biosíntesis , Osteoclastos/enzimología , Falla de Prótesis , Resorción Ósea/patología , Fibroblastos/patología , Humanos , Hibridación in Situ , Metaloproteinasas de la Matriz Asociadas a la Membrana , Osteoclastos/patología
19.
Ann Oncol ; 9(7): 711-6, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9739435

RESUMEN

BACKGROUND: Pegylated liposomal doxorubicin (PL-DOX) has been shown in preclinical models to induce less cardiotoxicity than non-liposomal doxorubicin. Endomyocardial biopsy is a highly sensitive and specific method for detecting anthracycline-induced cardiac damage. PATIENTS AND METHODS: Myocardial tissue from ten KS patients who had received cumulative PL-DOX (20 mg/m2/biweekly) of 440-840 mg/m2 was evaluated for evidence of anthracycline-induced cardiac damage. Controls were assembled from patients who had received cumulative doxorubicin doses of 174-671 mg/m2 in two earlier cardiac biopsy protocols. Two control groups were selected on the basis of both cumulative (+/- 10 mg/m2) and peak doxorubicin dose (60 or 20 mg/m2, control group 1), or peak dose alone (20 mg/m2, control group 2). RESULTS: PL-DOX patients had significantly lower biopsy scores compared with those of doxorubicin controls despite higher cumulative doses of anthracycline. The median biopsy scores for the PL-DOX and doxorubicin groups, respectively, were 0.3 vs. 3.0 (P = 0.002, Cochran-Mantel-Haenszel row mean difference test) for group 1 and 1.25 for group 2 (P < 0.001, Wilcoxon rank-sum test). CONCLUSIONS: Less severe cardiac changes were seen in patients given PL-DOX relative to historical control patients given comparable cumulative doses of doxorubicin.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Corazón/efectos de los fármacos , Miocardio/patología , Sarcoma de Kaposi/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Adulto , Anciano , Biopsia , Portadores de Fármacos , Femenino , Humanos , Liposomas , Masculino , Persona de Mediana Edad , Sarcoma de Kaposi/complicaciones , Estadísticas no Paramétricas
20.
J Thorac Cardiovasc Surg ; 116(3): 386-96, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9731779

RESUMEN

OBJECTIVE: We hypothesized that ex vivo hyperbaric transfection of antisense oligodeoxynucleotides for blockade of intercellular adhesion molecule-1, an important mediator of cell adhesion and T-cell co-stimulation, would reduce chronic graft vascular disease in cardiac allografts. METHODS: PVG hearts underwent ex vivo transfection with antisense, reverse antisense intercellular adhesion molecule-1 oligodeoxynucleotide (80 micromol/L), or saline solution at 3 atm pressure for 45 minutes at 4 degrees C and were transplanted heterotopically into ACI recipients with or without treatment with intercellular adhesion molecule-1 (1A29) or leukocyte function associated antigen-1 (WT.1) monoclonal antibodies. Transfection efficiency was confirmed with fluorescein isothiocyanate-labeled oligodeoxynucleotides and fluorescent microscopy. Efficacy of intracellular adhesion molecule-1 blockade was assessed with the use of immunohistochemistry. Graft reperfusion injury was evaluated at 6 to 24 hours by neutrophil infiltration (myeloperoxidase [MPO]), cardiac edema (%wt/wt), and histologic injury (percent contraction band necrosis). Grafts from recipients treated with cyclosporine A (5 mg/kg per day, days 0 to 9) were scored for chronic graft vascular disease on postoperative day 90 ranging from 0 (no involvement) to 4 (>50% vascular occlusion). RESULTS: Transfection was highly efficient (fluorescein isothiocyanate-labeled oligodeoxynucleotides in 48%+/-5% of total myocardial nuclei) and effective at blocking intracellular adhesion molecule-1 expression (positive area in allografts taken on postoperative day 3 was reduced from 100%+/-0% to 52%+/-14%, n=4). Blockade with antisense oligodeoxynucleotides versus monoclonal antibodies was less effective at preventing reperfusion injury while more effective at reducing chronic graft vascular disease (score 0.98+/-0.48, p < 0.05). Reverse antisense oligodeoxynucleotides and vector control (antisense oligodeoxynucleotide infusion without pressure) groups failed to demonstrate this beneficial effect. CONCLUSION: Hyperbaric transfection of antisense oligodeoxynucleotides proved highly efficient, effective at blockade of intracellular adhesion molecule-1, and demonstrated a sequence-specific reduction in chronic graft vascular disease. This highly targeted alteration of donor organ immunogenicity may have an important future role in clinical immunosuppressive strategies.


Asunto(s)
Enfermedad Coronaria/prevención & control , Terapia Genética/métodos , Trasplante de Corazón , Molécula 1 de Adhesión Intercelular/genética , Daño por Reperfusión Miocárdica/prevención & control , Complicaciones Posoperatorias/prevención & control , Transfección , Animales , Enfermedad Coronaria/etiología , Enfermedad Coronaria/inmunología , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Trasplante de Corazón/efectos adversos , Terapia de Inmunosupresión/métodos , Molécula 1 de Adhesión Intercelular/fisiología , Masculino , Daño por Reperfusión Miocárdica/etiología , Daño por Reperfusión Miocárdica/inmunología , Oligonucleótidos Antisentido/uso terapéutico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/inmunología , Presión , Ratas , Ratas Endogámicas ACI , Ratas Endogámicas , Trasplante Heterotópico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA