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1.
Ann Surg Oncol ; 21 Suppl 4: S546-54, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24562936

RESUMO

BACKGROUND: In the tumor microenvironment, factors inhibiting the targeting of cancer cells by activated T cells have recently been noted. B7-H3 belongs to the B7 superfamily of immune regulatory ligands and plays an important role in the adaptive immune response of co-inhibitory/stimulatory factors in regulating T cells. However, the degree to which B7-H3 directly affects tumor immune evasion mechanisms remains unclear, particularly in patients with breast cancer. Regulatory T cells (Tregs) are known as a key player in the inhibition of immune mechanisms. The present study demonstrated that expression of B7-H3 on tumor cells and the number of Tregs in the tumor microenvironment independently affected prognosis in breast cancer patients. METHODS: We immunohistochemically investigated the presence of B7-H3 and forkhead box P3 (Foxp3)-positive Tregs in pathological specimens from 90 patients with breast cancer. RESULTS: Positive B7-H3 expression was associated with shorter recurrence-free survival (RFS) (p = 0.014). A higher percentage of Foxp3-positive cells also correlated with shorter RFS (p = 0.039). Multivariate analysis showed B7-H3 as an independent factor on RFS. Foxp3 expression in tumor-infiltrating lymphocytes (TILs) correlated significantly with larger tumor size (>2 cm), expression of human epidermal growth factor receptor 2 (HER2), and higher nuclear grade (p = 0.003, p < 0.001, p = 0.001, respectively). No correlation was identified between expression of B7-H3 and the percentage of Foxp3-positive TILs. CONCLUSIONS: B7-H3 and Foxp3 can be regarded as markers of poor prognosis in breast cancer. These expressions were not correlated, suggesting that B7-H3 expression plays an independent role in tumor immune evasion, regardless of Tregs.


Assuntos
Antígenos B7/análise , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Linfócitos do Interstício Tumoral , Linfócitos T Reguladores , Evasão Tumoral , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/imunologia , Carcinoma Ductal de Mama/patologia , Intervalo Livre de Doença , Feminino , Fatores de Transcrição Forkhead/análise , Humanos , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/química , Pessoa de Meia-Idade , Receptor ErbB-2/análise , Taxa de Sobrevida , Linfócitos T Reguladores/química , Carga Tumoral , Microambiente Tumoral/imunologia
2.
Leukemia ; 27(2): 464-72, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22828443

RESUMO

Tumor-associated B7-H1 molecules inhibit antitumor immunity in some malignancies. We found that B7-H1 expression on patient myeloma cells and human myeloma cell lines (HMCLs) was upregulated by cultivating the cells with autologous stromal cells and the human stromal cell line HS-5. Among major cytokines produced by HS-5 cells, interleukin (IL)-6-induced B7-H1 expression on HMCLs. Moreover, HS-5 cell-mediated B7-H1 expression was downregulated by inhibiting IL-6. B7-H1(+) HMCLs were more proliferative and less susceptible to antimyeloma chemotherapy compared with B7-H1(-) HMCLs. Moreover, the former cells showed higher levels of Bcl-2 and FasL expression than the latter. Finally, B7-H1 molecules on HMCLs induced T-cell apoptosis and anergy of tumor-specific T cells. Consistent with these in vitro observations, patients whose myeloma cells expressed high levels of B7-H1 had higher myeloma cell percentages in the bone marrow (BM) and higher serum lactate dehydrogenase levels compared with other myeloma patients. In addition, B7-H1 expression levels were often upregulated after myeloma patients relapsed or became refractory to therapy. Our data indicate that the BM microenvironment upregulates B7-H1 expression on myeloma cells, which links to the two biological actions of inducing T-cell downregulation and enhancing aggressive myeloma-cell characteristics. Modulating the B7-H1 pathway may be worthwhile in myeloma.


Assuntos
Antígeno B7-H1/metabolismo , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Células Estromais/patologia , Linfócitos T Citotóxicos/imunologia , Apoptose , Antígeno B7-H1/genética , Western Blotting , Proliferação de Células , Proteína Ligante Fas/genética , Proteína Ligante Fas/metabolismo , Citometria de Fluxo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Ativação Linfocitária , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/metabolismo , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/imunologia , Células Estromais/metabolismo , Células Tumorais Cultivadas
4.
Pancreatology ; 11(4): 390-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21894056

RESUMO

BACKGROUND: Metastasis to the pancreas (MP) is a rare entity that is difficult to identify by imaging alone. Few reports have described endoscopic ultrasound (EUS) and EUS-guided fine-needle aspiration (FNA) findings. Herein, we try to describe the EUS and EUS-FNA characteristics of MP. METHODS: This retrospective study compared 28 patients with MP (13 males; mean age: 60.1 ± 12.6 years) and 60 control patients (30 males; 62.7 ± 11.5 years) with pancreatic ductal adenocarcinoma (PDAC). All lesions were characterized by EUS, and MP was diagnosed by EUS-FNA (n = 16), surgery (n = 6) or both (n = 6). RESULTS: Multivariate logistic regression revealed that the presence of regular borders (p = 0.004; OR: 8.81, 95% CI: 1.97-39.4), the absence of retention cysts (p = 0.045; OR: 12.5, 95% CI: 1.06-147.0), and the absence of main pancreatic duct (MPD) dilation (p = 0.003; OR: 8.18, 95% CI: 2.04-32.8) were predictors of MP rather than PDAC. The EUS-FNA sampling adequacy was 95.4% (21/22), and the correct diagnosis was obtained in 95.2% (20/21) of cases when K-ras mutation analysis and/or immunostaining were added. CONCLUSION: The presence of regular borders, the absence of retention cysts and the presence of nondilated MPD on EUS indicate MP rather than PDAC. This diagnosis can be accurately confirmed by EUS-FNA with immunostaining and/or K-ras analysis.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico , Endoscopia do Sistema Digestório/métodos , Endossonografia/métodos , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/secundário , Biópsia por Agulha Fina/métodos , Carcinoma Ductal Pancreático/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Hospitais de Ensino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Retrospectivos
5.
Phys Rev Lett ; 106(14): 146101, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21561204

RESUMO

We demonstrate a new method to switch on and off the rotational motion of a long-chain molecule by controlling the bonding geometry between the molecule and a substrate. An azobenzene derivative molecule adsorbed on a Au(111) surface is immobile only when its three rotation centers, comprised of two phenyl rings and a nitrogen-nitrogen bond, are located at hollow sites of the Au(111) surface, as observed by scanning tunneling microscopy. Rotational motion can be activated by exciting the vibrational modes and inducing hopping motion away from the immobile site with a voltage pulse.

7.
Br J Ophthalmol ; 94(2): 202-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19692386

RESUMO

AIMS: To determine the sensitivity and specificity of the photopic negative response (PhNR) of the focal electroretinograms (ERG; focal PhNR) to detect glaucomatous eyes with different degrees of visual field defects. METHODS: One-hundred and fourteen eyes of 114 patients with open angle glaucoma and 42 eyes of 42 normal controls were studied. The focal ERGs were elicited by a 15 degrees stimulus spot centred on the macula, and on the supero-temporal and on the infero-temporal areas of the macula. The receiver operating characteristic curves were determined to obtain optimal cut-off values. Eyes were classified as being glaucomatous when their focal PhNRs were less than the cut-off values in either retinal area (combined criterion). RESULTS: The focal PhNR amplitudes were significantly reduced with an advance in the stage of glaucoma. In early glaucoma, the sensitivities of the PhNR measured for each retinal area ranged from 58.1% to 80.7%. The sensitivities were significantly increased to 90.6% and 96.9% for the focal PhNR amplitude and the focal PhNR/b-wave amplitude ratio, respectively, when the combined criterion was employed. The specificity was >90%. CONCLUSIONS: Focal PhNRs have diagnostic ability in detecting early glaucoma with high sensitivity and specificity, especially when the combined criterion is used.


Assuntos
Glaucoma de Ângulo Aberto/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Diagnóstico Precoce , Eletrorretinografia/métodos , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Processamento de Sinais Assistido por Computador , Testes de Campo Visual , Campos Visuais/fisiologia
8.
Oncogene ; 28(36): 3197-208, 2009 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-19561643

RESUMO

The receptor tyrosine kinase Ror2 regulates cell migration by acting as a receptor or co-receptor for Wnt5a. Although Wnt5a has been implicated in the invasiveness of several types of tumors, the role of Ror2 in tumor invasion remains elusive. Here we show that osteosarcoma cell lines SaOS-2 and U2OS show invasive properties in vitro by activating Wnt5a/Ror2 signaling in a cell-autonomous manner. The suppressed expression of either Wnt5a or Ror2 in osteosarcoma cells inhibits cell invasiveness accompanying decreased invadopodia formation. Gene-expression profiling identified matrix metalloproteinase 13 (MMP-13) as one of the genes whose expression is downregulated in SaOS-2 cells following suppression of Ror2 expression. Reduced expression or activity of MMP-13 suppresses invasiveness of SaOS-2 cells. Moreover, expression of MMP-13 and cell invasiveness by Wnt5a/Ror2 signaling can be abrogated by an inhibitor of the Src-family protein tyrosine kinases (SFKs), suggesting the role of the SFKs in MMP-13 expression through Wnt5a/Ror2 signaling. We further show that activation of an SFK is inhibited by the suppressed expression of Ror2. Collectively, these results indicate that Wnt5a/Ror2 signaling involves the activation of a SFK, leading to MMP-13 expression, and that constitutively active Wnt5a/Ror2 signaling confers invasive properties on osteosarcoma cells in a cell-autonomous manner.


Assuntos
Movimento Celular/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/fisiologia , Proteínas Wnt/metabolismo , Proteína Tirosina Quinase CSK , Linhagem Celular Tumoral , Movimento Celular/genética , Ativação Enzimática/efeitos dos fármacos , Matriz Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Immunoblotting , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Microscopia de Fluorescência , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Pirimidinas/farmacologia , RNA Interferente Pequeno/genética , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Receptores de Superfície Celular/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transfecção , Proteínas Wnt/genética , Proteína Wnt-5a , Quinases da Família src
9.
Langmuir ; 21(26): 12146-52, 2005 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-16342986

RESUMO

Asymmetrically substituted poly(paraphenylene) (PhPPP) with hydrophilic and hydrophobic side chains was investigated. The polymer behavior at the air-water interface was studied on the basis of surface pressure-area (pi-A) isotherms and compression/expansion hysteresis measurements. PhPPP can form stable monolayers with an area per repeat unit of A=0.20+/-0.02 nm2 and a collapse pressure in the range of pi=25 mN/m. Then, Langmuir-Blodgett-Kuhn (LBK) films of PhPPP were prepared by horizontally and vertically transferring the Langmuir monolayers onto hydrophilic solid substrates at pi=12 mN/m. Cross-section analysis of the AFM tapping-mode topography images of a single transferred monolayer reveals a thickness of d0=0.9+/-0.1 nm. Taking into account the obtained monolayer thickness, curve-fitting calculations of angular scan data of LB monolayers measured using surface plasmon resonance (SPR) spectroscopy lead to a value for the refractive index of n=1.78+/-0.02 at lambda=632.8 nm. Next, the spontaneous formation of a PhPPP monolayer by adsorption from solution was studied ex situ by atomic force microscopy and UV-vis spectroscopy and in situ by using SPR spectroscopy. Stable self-assembled monolayers of PhPPP can be formed on hydrophilic surfaces with a thickness similar to that of the monolayer obtained using the LB method. The characterization results confirmed the amphiphilic character and the self-assembly properties of PhPPP, as well as the possibility of preparing homogeneous monolayer and multilayer films.


Assuntos
Polímeros/química , Adsorção , Cinética , Microscopia de Força Atômica , Espectrofotometria Ultravioleta
10.
Gut ; 54(1): 33-9, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15591501

RESUMO

BACKGROUND AND AIMS: In the progression of chronic gastritis, gastric mucosal cells deviate from the normal pathway of gastric differentiation to an intestinal phenotype which is closely related to gastric carcinoma. However, to date, it has not been elucidated whether the intestinal metaplasia is merely a change in the epithelium or whether the underlying mesenchyme also changes from gastric type to intestinal type. We have investigated the relationship between intestinal metaplasia and the pericryptal fibroblast sheath (PCFS) in the mesenchyme. In addition, we also examined PCFS in gastric carcinoma. METHODS: We determined the existence of PCFS in the intestinal metaplastic mucosa and carcinoma of both human and Cdx2 transgenic mouse stomach. PCFS was determined using the antibody against alpha-smooth muscle actin and electron microscopic observations. RESULTS: PCFS formed an almost complete layer around the small and large intestinal crypts while it did not exist around the normal gastric glands in both mice and humans. PCFS was seen around the glands of intestinal metaplastic mucosa in both Cdx2 transgenic mouse and human stomachs. However, PCFS was virtually absent in the intestinal-type gastric adenocarcinoma area. CONCLUSION: We successfully demonstrated that the epithelium as well as the mesenchyme changed from the gastric type to the intestinal type in intestinal metaplasia and that PCFS disappeared in intestinal-type gastric carcinoma.


Assuntos
Adenocarcinoma/patologia , Fibroblastos/patologia , Mucosa Gástrica/patologia , Neoplasias Gástricas/patologia , Actinas/metabolismo , Adenocarcinoma/metabolismo , Animais , Fator de Transcrição CDX2 , Fibroblastos/ultraestrutura , Mucosa Gástrica/metabolismo , Mucosa Gástrica/ultraestrutura , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Metaplasia/patologia , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/metabolismo , Neoplasias Gástricas/metabolismo , Fatores de Transcrição
11.
Gut ; 52(10): 1487-93, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12970143

RESUMO

BACKGROUND AND AIM: The present study was conducted to examine the effect of activin A on activation of rat pancreatic stellate cells (PSCs). METHODS: PSCs were prepared from rat pancreas using collagenase digestion and centrifugation with Nycodenz gradient. Activation of PSCs was examined by determining smooth muscle actin expression with western blotting. The presence of activin A receptors in PSCs was investigated by reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and immunocytochemistry. Expression of activin A and transforming growth factor beta (TGF-beta) mRNA was examined by RT-PCR. Activin A and TGF-beta peptide concentrations were examined with ELISA. Existence of activin A peptide in PSCs was investigated by immunocytochemistry. Collagen secretion was determined by Sirius red dye binding. RESULTS: Activin A receptors I and IIa were present in PSCs. PSCs expressed activin A mRNA and secreted activin A. Activin A enhanced PSC activation and collagen secretion in a dose dependent manner. TGF-beta and activin A increased each other's secretion and mRNA expression of PSCs. Follistatin decreased TGF-beta mRNA expression and TGF-beta secretion of PSCs, and inhibited both PSC activation and collagen secretion. CONCLUSION: Activin A is an autocrine activator of PSCs. Follistatin can inhibit PSC activation and collagen secretion by blocking autocrined activin A and decreasing TGF-beta expression and secretion of PSCs.


Assuntos
Ativinas/farmacologia , Comunicação Autócrina , Folistatina/farmacologia , Subunidades beta de Inibinas/farmacologia , Pâncreas/efeitos dos fármacos , Proteínas , Actinas/análise , Receptores de Ativinas Tipo I/análise , Receptores de Ativinas Tipo I/genética , Receptores de Activinas Tipo II/análise , Receptores de Activinas Tipo II/genética , Ativinas/análise , Ativinas/metabolismo , Animais , Western Blotting/métodos , Células Cultivadas , Colágeno/metabolismo , Relação Dose-Resposta a Droga , Fibrose , Folistatina/uso terapêutico , Subunidades beta de Inibinas/análise , Subunidades beta de Inibinas/metabolismo , Microscopia de Fluorescência , Pâncreas/química , Pâncreas/metabolismo , RNA Mensageiro/análise , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/análise , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/farmacologia
13.
Abdom Imaging ; 27(5): 549-51, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12172995

RESUMO

BACKGROUND: Percutaneous canalization of the bile duct is essential for radiologic interventions of the biliary tract. This study discusses technical considerations for safe approaches for canalization of the bile duct when using a sheath. METHODS: During early and late periods, percutaneous canalization was performed in 104 patients and 79 patients with malignant biliary stenosis, respectively. The late period differed from the early period in that the bile duct was canalized with a previously placed sheath to prevent catheter dislodgement during the procedure. RESULTS: During the early and late periods, catheter dislodgement during canalization occurred in three of 104 patients (3%) and none of 79 patients (0%), respectively. The success rate of canalization without cholangioscopy in the late period (99%) was better than that in the early period (89%; p < 0.05). CONCLUSION: Placement of a sheath into the biliary tree increases the safety and success of canalization in patients with malignant stenosis.


Assuntos
Ductos Biliares , Neoplasias do Sistema Biliar/complicações , Cateterismo/métodos , Colestase/terapia , Drenagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Colangiografia , Colestase/etiologia , Drenagem/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Intervencionista/métodos
14.
Gut ; 50(3): 326-31, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11839709

RESUMO

BACKGROUND: When endoscopic retrograde cholangiopancreatography (ERCP) guided bile duct biopsy fails to demonstrate malignancy, it remains unclear how to manage patients with presumably malignant strictures. AIMS: To evaluate the value of intraductal ultrasonography (IDUS) when bile duct biopsy is negative. METHODS: Sixty two patients with strictures of the bile duct were studied prospectively. During ERCP, IDUS was performed using an ultrasonic probe (diameter 2.0 mm; frequency 20 MHz). Following IDUS, a bile duct biopsy was performed using forceps (diameter 1.8 mm). The IDUS images of the tumour were classified as polypoid lesions, localised wall thickening, intraductal sessile tumours, sessile tumour outside of the bile duct, or absence of apparent lesion. The bile duct wall structures at the site of the tumour as well as the maximum diameter of the tumour were also analysed. The IDUS findings were compared with the histological findings or clinical course. RESULTS: When the IDUS images showed a polypoid lesion (n=19), localised wall thickening (n=8), intraductal sessile tumour (n=13), and sessile tumour outside of the bile duct (n = 20), the sensitivities of the biopsy were 80%, 50%, 92%, and 53%, respectively. Multiple regression analysis showed that the presence of sessile tumour (intraductal or outside of the bile duct: p<0.05), tumour size greater than 10.0 mm (p<0.001), and interrupted wall structure (p<0.05) were independent variables that predicted malignancy. CONCLUSION: When biopsy fails to demonstrate evidence of malignancy, the presence of sessile tumour (intraductal or outside of the bile duct), tumour size greater than 10.0 mm, and interrupted wall structure on IDUS images are factors that can predict malignancy.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colestase/etiologia , Endossonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/complicações , Neoplasias dos Ductos Biliares/patologia , Biópsia/métodos , Colangiopancreatografia Retrógrada Endoscópica , Reações Falso-Negativas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Sensibilidade e Especificidade
15.
J Clin Invest ; 108(12): 1771-80, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11748260

RESUMO

Costimulatory molecules on antigen-presenting cells (APCs) play an important role in T cell activation and expansion. However, little is known about the surface molecules involved in direct T-T cell interaction required for their activation and expansion. LIGHT, a newly discovered TNF superfamily member (TNFSF14), is expressed on activated T cells and immature dendritic cells. Here we demonstrate that blockade of LIGHT activity can reduce anti-CD3-mediated proliferation of purified T cells, suggesting that T cell-T cell interaction is essential for this proliferation. To test the in vivo activity of T cell-derived LIGHT in immune homeostasis and function, transgenic (Tg) mice expressing LIGHT in the T cell lineage were generated. LIGHT Tg mice have a significantly enlarged T cell compartment and a hyperactivated peripheral T cell population. LIGHT Tg mice spontaneously develop severe autoimmune disease manifested by splenomegaly, lymphadenopathy, glomerulonephritis, elevated autoantibodies, and severe infiltration of various peripheral tissues. Furthermore, the blockade of LIGHT activity ameliorates the severity of T cell-mediated diseases. Collectively, these findings establish a crucial role for this T cell-derived costimulatory ligand in T cell activation and expansion; moreover, the dysregulation of T cell-derived LIGHT leads to altered T cell homeostasis and autoimmune disease.


Assuntos
Doenças Autoimunes/etiologia , Proteínas de Membrana/fisiologia , Linfócitos T/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Linhagem da Célula , Citocinas/biossíntese , Homeostase , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral
16.
J Immunol ; 167(9): 5099-105, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11673520

RESUMO

Negative selection refers to the selective deletion of autoreactive thymocytes but its molecular events have not been well defined. In this study, we demonstrate that a cellular ligand for herpes virus entry mediator and lymphotoxin receptor (LIGHT), a newly identified member of the TNF superfamily, may play a critical role in negative selection. Using TCR transgenic mice, we find that the blockade of LIGHT signaling in vitro and in vivo prevents negative selection induced by peptide and intrathymically expressed Ags, resulting in the rescue of thymocytes from apoptosis. Furthermore, the thymi of LIGHT transgenic mice show severe atrophy with remarkably reduced CD4(+)CD8(+) double-positive cells caused by increased apoptosis, suggesting that LIGHT can delete immature T cells in vivo. Taken together, these results demonstrate a critical role of LIGHT in thymic negative selection of the T cell repertoire.


Assuntos
Proteínas de Membrana/fisiologia , Linfócitos T/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Apoptose , Isoanticorpos/fisiologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Receptores de Antígenos de Linfócitos T/fisiologia , Timo/citologia , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral
17.
Intervirology ; 44(5): 283-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11684889

RESUMO

OBJECTIVE: Epstein-Barr virus (EBV) nuclear antigen-1 (EBNA-1) and the replication origin, oriP, are essential for the replication and maintenance of latent EBV DNA in cells, but no enzymatic activity has been associated with EBNA-1 protein alone. In this study, we have searched for host cellular proteins that interact with EBNA-1 protein in various B cell lines latently infected with EBV, including a recently EBV growth-transformed cell line. METHODS: By using gel shift analysis, we investigated the interactions of an oligonucleotide containing a single EBNA-1 recognition site, derived from the family of repeats (FR) element of oriP, with protein from cell extracts. RESULTS: The FR oligonucleotide bound a (72-kD) cellular protein in the absence of EBNA-1 and without induction of the previously reported 'anti-EBNA-1 proteins'. The FR oligonucleotide formed complexes with additional proteins from EBNA-1-synthesizing cell lines; these complexes were abolished or supershifted by anti-EBNA-1 monoclonal antibodies. SDS-PAGE analyses of 35S-Met-labeled proteins that bound to a biotin- conjugated FR oligonucleotide, fractionated by a glycerol gradient centrifugation and affinity-purified with streptavidin, showed three major bands, a 72-kD protein, the FR binding of which seemed to be independent of EBNA-1, a 64-kD protein in both EBNA-1-transfected and latently EBV-infected cell lines, and a 45-kD protein in EBV-infected cell lines, which was most prominent in a recently EBV growth-transformed cell line. CONCLUSIONS: The FR element forms complexes with cellular proteins in the absence and presence of EBNA-1. These 72-, 64- and 45-kD cellular proteins might be involved in the function of the oriP and EBNA-1 system.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Antígenos Nucleares do Vírus Epstein-Barr/fisiologia , Herpesvirus Humano 4/genética , Oligodesoxirribonucleotídeos/metabolismo , Origem de Replicação/genética , Sítios de Ligação , Linfoma de Burkitt , Extratos Celulares , Centrifugação com Gradiente de Concentração , Sequência Consenso/genética , Ensaio de Desvio de Mobilidade Eletroforética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Humanos , Oligodesoxirribonucleotídeos/genética , Ligação Proteica , Transfecção , Células Tumorais Cultivadas
19.
Endoscopy ; 33(9): 808-10, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11558037

RESUMO

A case of symptomatic duodenal duplication cyst is reported. The patient underwent endoscopic partial resection of the cystic wall using the O-ring ligation kit. After resection, the abdominal pain disappeared. Endoscopic partial resection is useful for diagnosis and treatment of duodenal duplication cyst.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica , Cistos/diagnóstico , Cistos/cirurgia , Duodenopatias/diagnóstico , Duodenopatias/cirurgia , Duodeno/anormalidades , Duodeno/cirurgia , Adulto , Cistos/diagnóstico por imagem , Duodenopatias/diagnóstico por imagem , Duodeno/diagnóstico por imagem , Feminino , Humanos , Ultrassonografia
20.
J Gastroenterol ; 36(7): 492-4, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11480794

RESUMO

PURPOSE: Because biopsy forceps tend to turn towards the right hepatic duct during endoscopic retrograde cholangiopancreatography (ERCP), selective access to the left hepatic duct is difficult. METHODS: In this study, we managed to insert biopsy forceps selectively into the left hepatic duct, by using a looping technique, in three patients. Biopsy forceps were inserted into the right hepatic duct by the conventional method. The elevator of the endoscope was kept down, and the shaft of the biopsy forceps was then advanced to the duodenal cavity until it formed a loop between the endoscope and the papilla. During the procedure, the tip of the forceps was kept at the hepatic hilus. RESULTS: In this condition, we were able to slowly rotate the tip of the forceps and direct the forceps towards the left. Sufficient material from the left hepatic duct was obtained in all patients. CONCLUSIONS: The looping technique was useful for selective access to the left hepatic duct.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Biópsia/métodos , Colangiopancreatografia Retrógrada Endoscópica , Adulto , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Biópsia/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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