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1.
Anim Biosci ; 34(3): 393-404, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32882776

RESUMEN

OBJECTIVE: This study compared the catechin composition of different tea byproducts and investigated the effects of dietary supplementation with green tea byproducts on the accumulation of abdominal fat, the modulation of lipid metabolism, and the inflammatory response in red feather native chickens. METHODS: Bioactive compounds were detected, and in vitro anti-obesity capacity analyzed via 3T3-L1 preadipocytes. In animal experiments, 320 one-day-old red feather native chickens were divided into 4 treatment groups: control, basal diet supplemented with 0.5% Jinxuan byproduct (JBP), basal diet supplemented with 1% JBP, or basal diet supplemented with 5×106 colony-forming unit (CFU)/kg Bacillus amyloliquefaciens+5×106 CFU/kg Saccharomyces cerevisiae (BA+SC). Growth performance, serum characteristics, carcass characteristics, and the mRNA expression of selected genes were measured. RESULTS: This study compared several cultivars of tea, but Jinxuan showed the highest levels of the anti-obesity compound epigallocatechin gallate. 3T3-L1 preadipocytes treated with Jinxuan extract significantly reduced lipid accumulation. There were no significant differences in growth performance, serum characteristics, or carcass characteristics among the groups. However, in the 0.5% JBP group, mRNA expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) were significantly decreased. In the 1% JBP group, FAS, ACC and peroxisome proliferator-activated receptor γ levels were significantly decreased. Moreover, inflammation-related mRNA expression levels were decreased by the addition of JBP. CONCLUSION: JBP contained abundant catechins and related bioactive compounds, which reduced lipid accumulation in 3T3-L1 preadipocytes, however there was no significant reduction in abdominal fat. This may be due to a lack of active anti-obesity compounds or because the major changes in fat metabolism were not in the abdomen. Nonetheless, lipogenesis-related and inflammation-related mRNA expression were reduced in the 1% JBP group. In addition, dietary supplementation with tea byproducts could reduce the massive amount of byproducts created during tea production and modulate lipid metabolism and the inflammatory response in chickens.

2.
Anim Biosci ; 34(2): 265-275, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32138471

RESUMEN

OBJECTIVE: The study developed mushroom stalk residues as feed additives in the broiler diet for improving the growth performance and immunity of broilers as well as to increase the value of mushroom stalk residues. METHODS: In total, 300 ROSS 308 broilers were randomly allocated into fifteen pens with five dietary treatments: i) control, basal diet; ii) CMWM, supplemented with 1% Cordyceps militaris waster medium (CM); iii) CMPE, supplemented with 0.5% CM+0.5% Pleurotus eryngii stalk residue (PE); iv) CMPS, supplemented with 0.5% CM+0.5% Pleurotus sajorcaju stalk residue (PS); v) CMFV, supplemented with 0.5% CM+0.5% Fammulina velutipes stalk residue (FV). RESULTS: The chemical analysis results showed that CM extracts, PE extracts, PS extracts, and FV extracts contain functional components such as polysaccharides and phenols and have both 2, 2-diphenyl-1-picryl-hydrazyl-hydrate scavenging and Ferrous scavenging capacities. The group CMWM saw increased body weight gain and feed conversion rate and the promotion of jejunum villus growth, but there is no significant difference in the intestinal bacteria phase. Antioxidant genes in the nuclear factor (erythroid-derived 2)-like 2 (Nrf2)- antioxidant responsive element pathway among the groups are significantly higher than that of the control group, especially in group CMWM. CONCLUSION: The mushroom stalk residues have antioxidant functional components, can improve the intestinal health and body weight gain of chickens, and can activate the antioxidant pathway of Nrf2 to increase the heme oxygenase-1 expression. The treatment with 1% CM was the most promising as a feed additive.

3.
Dis Esophagus ; 32(5)2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30239640

RESUMEN

Positive proximal resection margins are strongly associated with anastomotic recurrence in esophageal cancer. However, the prognostic significance of dysplastic proximal resection margins remains unclear. The aim of this study is to investigate whether the dysplastic proximal resection margin can predict anastomotic recurrence and overall survival in patients with esophageal squamous cell carcinoma. Between 2000 and 2014, patients with esophageal squamous cell carcinoma who received a nonpalliative resection and survived the perioperative period were included. Two expert pathologists independently reviewed the proximal resection margin status, which was classified as negative, dysplastic, or positive. The kappa statistic was used to test interobserver reliability. Anastomotic recurrence and overall survival served as the main outcome measures. The study cohort consisted of 469 patients (445 males and 27 females). There was an excellent interobserver agreement for negative (kappa = 0.88), dysplastic (kappa = 0.88), and positive (kappa = 1) proximal resection margins-which were identified in 418 (89.1%), 37 (7.9%), and 14 (3.0%) patients, respectively. After a median follow-up of 21.6 months, 30 (6.4%) patients developed an anastomotic recurrence. Compared with patients with negative proximal resection margins (24/418, 5.7%), the occurrence of anastomotic recurrence was more commonly observed in those with positive proximal resection margins (3/14, 21.4%, P = 0.017) but not in those with dysplastic proximal resection margins (3/37, 8.1%, P = 0.56). Multivariable Cox regression analysis identified positive proximal resection margins (hazard ratio: 5.93, P = 0.010) and advanced clinical stage (hazard ratio: 12.04, P = 0.023) as independent risk factors for anastomotic recurrence. Dysplastic proximal resection margins were not retained in the model as an independent predictor (hazard ratio: 1.38, P = 0.602). The 5-year overall survival rates of patients with negative (38.2%) and dysplastic margins (27.0%) were similar (P = 0.814), and significantly higher than that observed in those with positive proximal resection margins (9.5%, P = 0.015). In conclusion, dysplastic proximal resection margins can be identified in at least 7.9% of patients with esophageal squamous cell carcinoma, but neither they are associated with an increased risk of anastomotic recurrence nor they portend a poor overall survival.


Asunto(s)
Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago/cirugía , Esófago/patología , Esófago/cirugía , Recurrencia Local de Neoplasia/patología , Adulto , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Quimioradioterapia Adyuvante , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago/terapia , Femenino , Estudios de Seguimiento , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Neoplasia Residual , Variaciones Dependientes del Observador , Pronóstico , Modelos de Riesgos Proporcionales , Tasa de Supervivencia
4.
Oncogene ; 36(37): 5274-5284, 2017 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-28504722

RESUMEN

Infection by hepatitis B virus (HBV) accounts for 50-80% of hepatocellular carcinoma (HCC) development worldwide, in which the HBV-encoded X protein (HBx) has critical role in the induction of carcinogenesis. Several studies have shown that thyroid hormone (TH) suppresses HCC development and protects hepatocytes from HBx-induced damage, thus it is of interest to examine whether TH can protect hepatocytes from HBx-induced carcinogenesis. By treating HBx- transgenic mice with or without TH, we confirmed the protective effects of TH on HBx-induced hepatocarcinogenesis, which was achieved via reduction of reactive oxygen species (ROS) inflicted DNA damage. We further found that TH induced biogenesis of mitochondria (MITO) and autophagy of HBx-targeted MITO simultaneously, consequently leading to suppression of HBx-promoted ROS and carcinogenesis. Using microarray data analysis, this protective effect of TH was found to be mediated via activation of PTEN-induced kinase 1 (PINK1) in hepatocytes. PINK1, in turn, activated and recruited Parkin, an E3 ligase, to ubiquitinate MITO-associated HBx protein and trigger selective mitophagy. The pathological significance of the TH/PINK1 pathway in liver protection was confirmed by the concomitant decrease in expression of both TR and PINK1 in matched HCC tumor tissues and negatively correlated with aggressive progression of cancer and poor prognosis. Our data indicate that TH/PINK1/Parkin pathway has a critical role in protecting hepatocytes from HBx-induced carcinogenesis. Notably, several liver-targeting therapeutic derivatives of TH facilitating prevention or therapy of steatosis have been identified. Furthermore, our proof-of-concept experiments suggest that application of T3 constitutes an effective novel therapeutic or preventive option for HCC. Thus, the utilization of the agonists of TRs could be the meaningful strategy in liver relative diseases, ranging from simple hepatic steatosis to HCC.


Asunto(s)
Carcinogénesis/metabolismo , Hepatocitos/metabolismo , Hepatocitos/patología , Mitocondrias/metabolismo , Transactivadores/biosíntesis , Transactivadores/genética , Triyodotironina/metabolismo , Animales , Carcinogénesis/genética , Carcinogénesis/patología , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Daño del ADN , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/metabolismo , Masculino , Ratones , Ratones Transgénicos , Mitocondrias/genética , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Transducción de Señal , Proteínas Reguladoras y Accesorias Virales
5.
Eur J Surg Oncol ; 43(1): 234-239, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27462024

RESUMEN

BACKGROUND: The purpose of this study was to investigate the prognosis and its predictors in patients with esophageal squamous cell carcinoma (ESCC) who achieve major histopathological response (MaHR) after neoadjuvant chemoradiotherapy (nCRT). METHODS: We examined a total of 187 ESCC patients who achieved MaHR following nCRT and survived the perioperative period. MaHR was defined as either absence or <10% vital residual tumor cells (VRTC) in the resected esophagus without nodal involvement. Univariate and multivariate analyses were used to identify factors significantly associated with overall survival (OS). RESULTS: At the time of analysis, 113 patients (60.4%) were dead (5-year OS = 48%; median survival time = 54.8 months). The amount of VRTC (1-10% versus 0% VRTC; hazard ratio [HR] = 1.9, P < 0.001) and the thoroughness of histopathological examination (standard [≤ 4 tumor blocks] versus thorough [> 4 tumor blocks], HR = 1.57; P = 0.013) were independent predictors of OS in multivariate analysis. A stepwise increase in OS was observed in the following groups: patients with 1-10% VRTC identified by the standard protocol, patients with 1-10% VRTC identified by the thorough protocol, patients with 0% VRTC identified by the standard protocol, and patients with 0% VRTC identified by the thorough protocol (5-year OS rates = 20%, 40%, 50%, and 62%, respectively, P < 0.001). CONCLUSIONS: In ESCC patients who achieve MaHR after nCRT, the presence of microscopical residual disease and the thoroughness of histopathological examination are associated with survival.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Neoplasias Esofágicas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagectomía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
6.
Br J Surg ; 103(13): 1874-1879, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27620361

RESUMEN

BACKGROUND: A 'surgery as needed' strategy has been proposed for patients with oesophageal cancer who truly achieve a pathological complete response (pCR) following neoadjuvant chemoradiotherapy (nCRT). However, the ability to detect residual disease remains problematic. This study investigated the anatomical locations and pathological characteristics of residual cancer in patients with oesophageal squamous cell carcinoma (SCC) who achieved a near pCR following nCRT. METHODS: Patients with oesophageal SCC who achieved a near pCR after nCRT were eligible. Near pCR was defined as residual cancer in the resection specimen representing less than 10 per cent of the apparent original tumour area. RESULTS: Detailed histopathological reassessment of 76 consecutive patients (mean age 54·4 years) with a near pCR was undertaken. Some 32 patients (42 per cent) with a near pCR had no detectable mucosal lesions. Residual tumour was identified most frequently in the submucosal layer (54, 71 per cent), followed by the mucosa (44, 58 per cent), muscle layer (36, 47 per cent) and adventitia (22, 29 per cent) (P < 0·001). Among patients without ypT1a disease, increasing depth of tumour invasion correlated negatively with the likelihood of mucosal involvement. Of patients with ypT3 disease, 16 of 22 had no detectable cancer located in the mucosa, compared with six of 29 with ypT1b disease (P < 0·001). CONCLUSION: Better tools for predicting pCR are required before considering a 'surgery as needed' approach in the management of oesophageal cancer.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Neoplasia Residual/terapia , Adulto , Anciano , Anciano de 80 o más Años , Quimioradioterapia Adyuvante/métodos , Carcinoma de Células Escamosas de Esófago , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
7.
Am J Transplant ; 16(7): 2030-41, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26914847

RESUMEN

Tolerance induction by means of costimulation blockade has been successfully applied in solid organ transplantation; however, its efficacy in vascularized composite allotransplantation, containing a vascularized bone marrow component and thus a constant source of donor-derived stem cells, remains poorly explored. In this study, osteomyocutaneous allografts (alloOMCs) from Balb/c (H2(d) ) mice were transplanted into C57BL/6 (H2(b) ) recipients. Immunosuppression consisted of 1 mg anti-CD154 on day 0, 0.5 mg CTLA4Ig on day 2 and rapamycin (RPM; 3 mg/kg per day from days 0-7, then every other day for 3 weeks). Long-term allograft survival, donor-specific tolerance and donor-recipient cell trafficking were evaluated. Treatment with costimulation blockade plus RPM resulted in long-term graft survival (>120 days) of alloOMC in 12 of 15 recipients compared with untreated controls (median survival time [MST] ≈10.2 ± 0.8 days), RPM alone (MST ≈33 ± 5.5 days) and costimulation blockade alone (MST ≈45.8 ± 7.1 days). Donor-specific hyporesponsiveness in recipients with viable grafts was demonstrated in vitro. Evidence of donor-specific tolerance was further assessed in vivo by secondary donor-specific skin graft survival and third-party graft rejection. A significant increase of Foxp3(+) regulatory T cells was evident in tolerant animals. Donor cells populated peripheral blood, thymus, and both donor and recipient bone marrow. Consequently, combined anti-CD154/CTLA4Ig costimulation blockade-based therapy induces donor-specific tolerance in a stringent murine alloOMC transplant model.


Asunto(s)
Abatacept/inmunología , Trasplante de Médula Ósea , Ligando de CD40/inmunología , Tolerancia Inmunológica/inmunología , Colgajo Miocutáneo/irrigación sanguínea , Enfermedades de la Piel/inmunología , Donantes de Tejidos , Aloinjertos , Animales , Linfocitos T CD4-Positivos/inmunología , Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Inmunosupresores/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Sirolimus/farmacología , Enfermedades de la Piel/terapia , Acondicionamiento Pretrasplante
8.
Dis Esophagus ; 29(6): 544-50, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26123695

RESUMEN

There is a significant learning curve for endoscopic submucosal dissection of esophageal neoplasms that has not been fully characterized. This retrospective study included 33 consecutive superficial esophageal neoplasms for analysis of the learning curve for esophageal endoscopic submucosal dissection based on a single, novice endoscopist's experience. The study was divided into three periods (T1, T2, and T3) of 10 endoscopic submucosal dissection procedures in chronological order, with 13 procedures in the last period. Patient factors (age, sex, coexistent esophageal varices, or submucosal fibrosis) and tumor factors (location at upper esophagus, involving >3/4 esophageal circumference) for endoscopic submucosal dissection were not statistically different between the periods. The mean procedure time was 74.6 min/cm(2) , 23.4 min/cm(2) , and 10.5 min/cm(2) for T1, T2, and T3, respectively. The procedure time decreased over time (P = 0.02) and post hoc test revealed significant difference was only between T3 and T1 (P = 0.019). The en bloc resection rate was 50%, 100%, and 92.3% for T1, T2, and T3, respectively (P for trend = 0.015). R0 resection rate was 40%, 100%, and 84.6% for T1, T2, and T3, respectively (P for trend = 0.023). Two patients had complications: each one patient in T1 and T3 period experienced major bleeding during the procedure (P for trend = 0.875). None of the patients had esophageal perforation. The results of the study concluded that at least 30 cases of endoscopic submucosal dissection of esophageal neoplasms are needed for a novice endoscopist to gain early proficiency in this technique.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Resección Endoscópica de la Mucosa , Neoplasias Esofágicas/cirugía , Esofagoscopía , Curva de Aprendizaje , Adulto , Anciano , Carcinoma de Células Escamosas/epidemiología , Comorbilidad , Neoplasias Esofágicas/epidemiología , Carcinoma de Células Escamosas de Esófago , Várices Esofágicas y Gástricas/epidemiología , Femenino , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
9.
Br J Surg ; 102(8): 998-1005, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25974177

RESUMEN

BACKGROUND: The combination of fat grafting and negative pressure (VAC) therapy represents a synergistic interaction of all essential components for wound healing. The aim of this experimental study was to determine whether it could promote healing of wounds with exposed bone. METHODS: Full-thickness wounds with denuded bone in Sprague-Dawley rats were treated with either polyurethane foam dressing, fat grafting alone, polyurethane foam dressing with VAC, or polyurethane foam dressing with VAC combined with a single, or two administrations of fat graft. Wound healing kinetics, tissue growth, cell proliferation (Ki-67) and angiogenesis (platelet endothelial cell adhesion molecule 1 and α-smooth muscle actin) were investigated. Messenger RNA levels related to angiogenesis (vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (b-FGF)), profibrosis (platelet-derived growth factor A and transforming growth factor ß), adipocyte expression (fatty acid-binding protein (FABP) 4 and peroxisome proliferator activated receptor γ), and extracellular matrix remodelling (collagen I) were measured in wound tissues. RESULTS: Wounds treated by VAC combined with fat grafting were characterized by cell proliferation, neoangiogenesis and maturation of functional blood vessels; they showed accelerated granulation tissue growth over the denuded bone compared with VAC- or foam dressing-treated wounds. Fat grafting alone over denuded bone resulted in complete necrosis. Expression of angiogenesis markers (VEGF and b-FGF) and adipocyte expression factors (FABP-4) was upregulated in wounds treated with VAC combined with fat grafting. CONCLUSION: Fat grafting with VAC therapy may represent a simple but effective clinical solution for a number of complex tissue defects, and warrants testing in clinical models. SURGICAL RELEVANCE: The combination of fat grafting and vacuum therapy represents a synergistic interaction of regenerative cells, hospitable wound matrix and stimulating micromechanical forces. It could accelerate complex wound healing through cell proliferation, neoangiogenesis and maturation of functional blood vessels. The efficacy of a multimodal wound healing approach is established in this experimental model; it could easily be translated into clinical trials of treatment for difficult wounds.


Asunto(s)
Tejido Adiposo/trasplante , Huesos/fisiopatología , Terapia de Presión Negativa para Heridas , Cicatrización de Heridas/fisiología , Tejido Adiposo/patología , Animales , Proliferación Celular , Fibrosis , Tejido de Granulación/fisiología , Modelos Animales , Necrosis , Neovascularización Fisiológica , Ratas Sprague-Dawley , Cuero Cabelludo/lesiones , Trasplante Autólogo
12.
Acta Clin Belg ; 66(4): 302-4, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21938987

RESUMEN

Double malignancies in the gastrointestinal tract are unusual. Concurrent lymphoma and adenocarcinoma is a rare clinical condition. We herein report a collision tumour which first presented with a diffuse large B-cell lymphoma in the skull base and ileocecal junction area. After rituximab and chemotherapy the skull base tumour disappeared, but the ileocecal lesion remained. A biopsy revealed the presence of adenocarcinoma in the same lesion. The tumour was surgically removed. Further microscopic examination of the tumour showed it was an adenocarcinoma but residual lymphoma cell infiltration could still be observed. Serum Epstein-Barr virus (EBV) was detected at diagnosis of lymphoma and the concentration further elevated at diagnosis of adenocarcinoma. Therefore, both lymphoma and carcinoma may be EBV related. Our experience illustrated that such collision tumours are rare and difficult in diagnosis. Clinicians and pathologists should be aware of such an association in order to make a correct diagnosis and initiate proper treatment.


Asunto(s)
Adenocarcinoma/patología , Neoplasias del Colon/patología , Linfoma de Células B Grandes Difuso/patología , Neoplasias Primarias Múltiples/patología , Neoplasias de la Base del Cráneo/patología , Adenocarcinoma/tratamiento farmacológico , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Colonoscopía , Herpesvirus Humano 4/metabolismo , Humanos , Factores Inmunológicos/uso terapéutico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Masculino , Neoplasias Primarias Múltiples/tratamiento farmacológico , Rituximab
13.
Ultrasonics ; 51(2): 148-56, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20696449

RESUMEN

A new horn for high displacement amplification is developed. The profile of the horn is a cubic Bézier curve. The ultrasonic actuation of the horn exploits the first longitudinal displacement mode of the horn. A design method of the horn using an optimization scheme and finite element analyses is developed. Prototypes of the horns are manufactured by a numerical control machining process. Performances of the proposed horn have been evaluated by experiments. Experimental results of the harmonic response of the fabricated horn confirm the effectiveness of the design method. The displacement amplification of the proposed horn is 71% higher than that of the traditional catenoidal horn with the same length and end surface diameters.


Asunto(s)
Aumento de la Imagen/instrumentación , Transductores , Ultrasonografía/instrumentación , Algoritmos , Diseño de Equipo , Análisis de Elementos Finitos
14.
Autoimmunity ; 43(5-6): 413-27, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20380583

RESUMEN

Paraneoplastic autoimmune diseases associate occasionally with small cell lung cancers and gynecologic tumors. However, myasthenia gravis (MG) occurs in at least 30% of all patients with thymomas (usually present at MG diagnosis). These epithelial neoplasms almost always have numerous admixed maturing polyclonal T cells (thymocytes). This thymopoiesis-and export of mature CD4(+)T cells-particularly associates with MG, though there are rare/puzzling exceptions in apparently pure epithelial WHO type A thymomas. Other features potentially leading to inefficient self-tolerance induction include defective epithelial expression of the autoimmune regulator (AIRE) gene and/or of major histocompatibility complex class II molecules in thymomas, absence of myoid cells, failure to generate FOXP3(+) regulatory T cells, and genetic polymorphisms affecting T-cell signaling. However, the strong focus on MG/neuromuscular targets remains unexplained and suggests some biased autoantigen expression, T-cell selection, or autoimmunization within thymomas. There must be further clues in the intriguing serological and cellular parallels in some patients with late-onset MG but without thymomas-and in others with AIRE mutations-and in the contrasts with early-onset MG, as discussed here.


Asunto(s)
Miastenia Gravis/inmunología , Síndromes Paraneoplásicos del Sistema Nervioso/inmunología , Timoma/inmunología , Timo/fisiopatología , Autoanticuerpos/inmunología , Autoantígenos/inmunología , Autoantígenos/metabolismo , Células Epiteliales/patología , Genes MHC Clase II , Humanos , Inmunoglobulina G/inmunología , Linfopoyesis , Miastenia Gravis/genética , Miastenia Gravis/fisiopatología , Síndromes Paraneoplásicos del Sistema Nervioso/genética , Poliendocrinopatías Autoinmunes/inmunología , Linfocitos T/inmunología , Timoma/genética , Timoma/patología , Timoma/fisiopatología , Factores de Transcripción/genética , Proteína AIRE
16.
Genes Immun ; 10(8): 667-72, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19693092

RESUMEN

Protein tyrosine phosphatase, non-receptor type 22 (PTPN22) inhibits T-cell activation and interleukin-2 (IL-2) production. The PTPN22(gain-of-function)+1858T(+) genotypes predispose to multiple autoimmune diseases, including early-onset (non-thymomatous) myasthenia gravis (MG). The disease association and the requirement of IL-2/IL-2 receptor signaling for intrathymic, negative T-cell selection have suggested that these genotypes may weaken T-cell receptor (TCR) signaling and impair the deletion of autoreactive T cells. Evidence for this hypothesis is missing. Thymoma-associated MG, which depends on intratumorous generation and export of mature autoreactive CD4(+) T cells, is a model of autoimmunity because of central tolerance failure. Here, we analyzed the PTPN22 +1858C/T single nucleotide polymorphism in 426 German Caucasian individuals, including 125 thymoma patients (79 with MG), and investigated intratumorous IL-2 expression levels. Unlike two previous studies on French and Swedish patients, we found strong association of PTPN22 +1858T(+) genotypes not only with early-onset MG (P=0.00034) but also with thymoma-associated MG (P=0.0028). IL-2 expression in thymomas with PTPN22 +1858T(+) genotypes (P=0.028) was lower, implying weaker TCR signaling. We conclude that the PTPN22(gain-of-function) variant biases towards MG in a subgroup of thymoma patients possibly by impeding central tolerance induction.


Asunto(s)
Interleucina-2/inmunología , Miastenia Gravis/inmunología , Polimorfismo de Nucleótido Simple , Proteína Tirosina Fosfatasa no Receptora Tipo 22/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 22/inmunología , Timoma/inmunología , Neoplasias del Timo/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos CD/genética , Antígenos CD/inmunología , Antígeno CTLA-4 , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/complicaciones , Miastenia Gravis/genética , Timoma/complicaciones , Timoma/genética , Neoplasias del Timo/complicaciones , Neoplasias del Timo/genética , Población Blanca/genética , Adulto Joven
17.
Spinal Cord ; 45(9): 641-4, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17228357

RESUMEN

STUDY DESIGN: Case report. SETTING: Tertiary referral center hospital in Taiwan. OBJECTIVES: To report a case of spinal Rosai-Dorfman disease (RDD) presenting with paraparesis and also preceding by relapsing uveitis for 6 months. A thoracic laminectomy was performed to remove the solid mass. The pathological diagnosis reveals infiltrating histiocytes, emperipolesis and positivity for S-100. There is no recurrence 1 year later with MR imaging. CONCLUSIONS: The relapsing idiopathic uveitis may be a prodrome for this unusual disease, because RDD is associated closely to defective immunogical response. Early and accurate diagnosis of CNS RDD may reverse the neurologic deficits by early decompression.


Asunto(s)
Espacio Epidural/patología , Histiocitosis Sinusal/diagnóstico , Histiocitosis Sinusal/etiología , Enfermedades de la Columna Vertebral/diagnóstico , Enfermedades de la Columna Vertebral/etiología , Uveítis/complicaciones , Uveítis/diagnóstico , Espacio Epidural/inmunología , Femenino , Histiocitosis Sinusal/inmunología , Humanos , Recurrencia , Enfermedades de la Columna Vertebral/inmunología , Uveítis/inmunología
18.
J Biomed Mater Res ; 51(4): 761-70, 2000 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10880126

RESUMEN

To evaluate the biocompatibility of biodegradable polyesterurethane membranes with different surface morphologies for their possible use as orthopedic biomaterials, rat osteoblasts were cultured on smooth, sunken, and particulate polyesterurethane membranes. A close interaction between cells and exposed particles on the particulate membranes was found. Cells on the particulate surfaces were well spread and flattened and had the greatest adhesion while cells on the smooth surfaces were more rounded, less spread, and less adhered. In addition, in order to investigate their in vivo degradation rates, the morphologic changes in retrieved membranes from 2, 4, and 8 weeks after subcutaneous implantation were observed by scanning electron microscopy and their average molecular weight changes were determined by gel permeation chromatography. These analyses showed that smooth membranes, compared with the two other surface membrane types, had the greatest rate and degree of molecular weight change. In contrast, the molecular weight of particulate membranes, which favor the osteoblast culture, had not changed significantly at 8 weeks postimplantation. Thus particulate polyesterurethane membrane surfaces may be of use as an orthopedic biomaterial, and polyesterurethane membranes certainly provide an ideal system for further study of the relative contributions to biocompatibility and degradation derived from surface morphology.


Asunto(s)
Materiales Biocompatibles , Técnicas de Cultivo de Célula/métodos , Osteoblastos/citología , Poliésteres , Poliuretanos , Animales , Biodegradación Ambiental , Recuento de Células , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Ratas , Propiedades de Superficie
19.
Biomaterials ; 20(16): 1479-87, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10458561

RESUMEN

In this work, the properties of poly(vinyl alcohol) (PVA) and PVA/chitosan blended membranes were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and electron spectroscopy for chemical analysis (ESCA). The SEM photographs show the PVA/chitosan blended membrane undergoes dramatic changes on the surface and bulk structure during the membrane formation. The DSC analysis shows that PVA and chitosan are not very compatible in the PVA/chitosan blended membrane, whereas the combination of two polymer chains of constitutionally different features is revealed. In addition, the surface of the PVA/chitosan blended membrane is enriched with nitrogen atoms at the ESCA analysis. These reflect the PVA membrane can be modified by blending with chitosan that in turn may affect the biocompatibility of the blended membrane. Therefore, adhesion and growth of fibroblasts on the PVA as well as PVA/chitosan blended membranes were investigated. Cell morphologies on the membranes were examined by SEM and cell viability was studied using MTT assay. It was observed that the PVA/chitosan blended membrane was more favorable for the cell culture than the pure PVA membrane. Cells cultured on the PVA/chitosan blended membrane had good spreading, cytoplasm webbing and flattening and were more compacting than on the pure PVA membrane. Consequently, the PVA/chitosan blended membrane may spatially mediate cellular response that can promote cell attachment and growth, indicating the PVA/chitosan blended membrane should be useful as a biomaterial for cell culture.


Asunto(s)
Materiales Biocompatibles/farmacología , Células Cultivadas/efectos de los fármacos , Quitina/análogos & derivados , Fibroblastos/efectos de los fármacos , Membranas Artificiales , Alcohol Polivinílico/farmacología , Materiales Biocompatibles/química , Rastreo Diferencial de Calorimetría , Células Cultivadas/ultraestructura , Quitina/química , Quitina/farmacología , Quitosano , Fibroblastos/ultraestructura , Humanos , Ensayo de Materiales , Técnicas Microbiológicas , Microscopía Electrónica de Rastreo , Alcohol Polivinílico/química , Análisis Espectral
20.
J Biomed Mater Res ; 40(3): 385-91, 1998 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-9570069

RESUMEN

Islets of Langerhans surrounded by a semipermeable membrane to prevent an immune response by the host immunosystem is a potential way of treating type I diabetes mellitus. In this study, poly(vinyl alcohol) (PVA) tubular membranes with added polyethylene glycol to create pores in the skin layer were prepared to improve their diffusion property. In a static incubation study, islets cultured in the PVA tubular membranes still demonstrated their function of secreting insulin after 30 days. When the tubular PVA bioartificial pancreas was perifused in a small chamber with RPMI-1640 medium containing glucose at concentrations of 5.6-16.6 mmol/L, insulin release began to increase without delay. Therefore, such a membrane is an alternative potential material for a bioartificial pancreas. In addition, a mathematical mass transfer model of insulin release was developed and compared with the perifusion data. It was shown that satisfactory kinetics could be achieved with a PVA membrane. However, the model showed that the insulin output of islets cultured in the PVA tubular membrane must be increased to improve the performance significantly. These findings suggest that a bioartificial pancreas using a PVA membrane is a promising material, but the technique for seeding islets in the chamber requires further modification.


Asunto(s)
Membranas Artificiales , Modelos Biológicos , Páncreas Artificial , Alcohol Polivinílico , Animales , Difusión , Estudios de Evaluación como Asunto , Insulina/metabolismo , Secreción de Insulina , Masculino , Perfusión , Ratas , Ratas Wistar
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