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1.
Br J Surg ; 105(3): 192-202, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29405274

RESUMEN

BACKGROUND: Although some retrospective studies have suggested the value of adjuvant therapy, no recommended standard exists in bile duct cancer. The aim of this study was to test the hypothesis that adjuvant gemcitabine chemotherapy would improve survival probability in resected bile duct cancer. METHODS: This was a randomized phase III trial. Patients with resected bile duct cancer were assigned randomly to gemcitabine and observation groups, which were balanced with respect to lymph node status, residual tumour status and tumour location. Gemcitabine was given intravenously at a dose of 1000 mg/m2 , administered on days 1, 8 and 15 every 4 weeks for six cycles. The primary endpoint was overall survival, and secondary endpoints were relapse-free survival, subgroup analysis and toxicity. RESULTS: Some 225 patients were included (117 gemcitabine, 108 observation). Baseline characteristics were well balanced between the gemcitabine and observation groups. There were no significant differences in overall survival (median 62·3 versus 63·8 months respectively; hazard ratio 1·01, 95 per cent c.i. 0·70 to 1·45; P = 0·964) and relapse-free survival (median 36·0 versus 39·9 months; hazard ratio 0·93, 0·66 to 1·32; P = 0·693). There were no survival differences between the two groups in subsets stratified by lymph node status and margin status. Although haematological toxicity occurred frequently in the gemcitabine group, most toxicities were transient, and grade 3/4 non-haematological toxicity was rare. CONCLUSION: The survival probability in patients with resected bile duct cancer was not significantly different between the gemcitabine adjuvant chemotherapy group and the observation group. Registration number: UMIN 000000820 (http://www.umin.ac.jp/).


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Antimetabolitos Antineoplásicos/uso terapéutico , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Procedimientos Quirúrgicos del Sistema Biliar , Carcinoma Adenoescamoso/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de los Conductos Biliares/mortalidad , Neoplasias de los Conductos Biliares/cirugía , Carcinoma Adenoescamoso/mortalidad , Carcinoma Adenoescamoso/cirugía , Quimioterapia Adyuvante , Desoxicitidina/uso terapéutico , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intravenosas , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Resultado del Tratamiento , Gemcitabina
4.
Reprod Domest Anim ; 50(5): 872-80, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26138589

RESUMEN

The CRISPR/Cas9 system has enabled the editing of mammalian genomes; however, its applicability and efficiency in the pig genome has not been studied in depth. The α-gal epitope synthesized by α-1,3-galactosyltransferase gene (GGTA1) is known as a xenoantigen obtained upon pig-to-human xenotransplantation. We here employed the CRISPR/Cas9 system-mediated knock-in of endogenous GGTA1 via targeted homologous recombination (HR). Linearized donors with ~800-bp homology flanking the CRISPR/Cas9 target site [exon 4 (containing ATG) of GGTA1] served as a template for gene targeting by HR. Using a targeted toxin strategy to select clones lacking α-gal epitope expression, we successfully obtained several knock-in clones within 3 weeks of initial transfection. These results suggest that the use of CRISPR/Cas9-mediated HR to knock-in a mutated fragment at defined loci represents an efficient strategy to achieve the rapid modulation of genes of interest in swine cells and is a promising tool for the creation of KO piglets.


Asunto(s)
Sistemas CRISPR-Cas/genética , Fibroblastos/enzimología , Galactosiltransferasas/deficiencia , Técnicas de Sustitución del Gen/veterinaria , Sus scrofa/embriología , Animales , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Epítopos/genética , Galactosiltransferasas/genética , Recombinación Homóloga/genética , Mutación/genética , Transfección/veterinaria
5.
Br J Surg ; 100(4): 522-7, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23288577

RESUMEN

BACKGROUND: Postoperative chylous ascites following abdominal surgery is uncommon. It potentially induces malnutrition and immunodeficiency, contributing to increased mortality. In the field of hepatopancreatobiliary (HPB) surgery, no large studies have been conducted that focused on postoperative chylous ascites. The aim of this study was to determine the incidence, risk factors and management of chylous ascites following HPB surgery, with particular emphasis on pancreatic resection. METHODS: Consecutive patients who had HPB surgery between 2000 and 2011 at a single institution were reviewed retrospectively. Chyle leak was defined as 100 ml/day or more of milky, amylase-free peritoneal fluid with a triglyceride concentration of 110 mg/dl or above. Risk factors for chylous ascites associated with pancreatic resection and the clinical efficacy of octreotide in treating chylous ascites were evaluated. RESULTS: Of 2002 consecutive patients who underwent HPB surgery during the study period, 21 (1·0 per cent) developed chylous ascites. Chylous ascites occurred relatively frequently in patients who had a pancreatic resection, such as pancreaticoduodenectomy (3·3 per cent) or distal pancreatectomy (3·8 per cent). Multivariable analysis revealed that manipulation of the para-aortic area (P < 0·001), retroperitoneal invasion (P = 0·031) and early enteral feeding after operation (P < 0·001) were independent risk factors for chylous ascites following pancreatic resection. Octreotide treatment decreased drainage output of chylous ascites on day 1 after initiation of treatment (P = 0·002). CONCLUSION: Chylous ascites is a rare complication following HPB surgery. It is more common after pancreatic resection. Treatment with octreotide combined with total parenteral nutrition is recommended.


Asunto(s)
Enfermedades de las Vías Biliares/cirugía , Procedimientos Quirúrgicos del Sistema Biliar , Ascitis Quilosa/etiología , Páncreas/cirugía , Enfermedades Pancreáticas/cirugía , Complicaciones Posoperatorias/etiología , Ascitis Quilosa/tratamiento farmacológico , Femenino , Fármacos Gastrointestinales/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Octreótido/uso terapéutico , Pancreatectomía , Pancreaticoduodenectomía , Complicaciones Posoperatorias/tratamiento farmacológico , Estudios Retrospectivos , Factores de Riesgo
7.
Reprod Domest Anim ; 47(5): 759-65, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22136322

RESUMEN

Porcine embryonic fibroblasts (PEFs) are widely used as donor cells for somatic cell nuclear transfer (SCNT) in pigs. Transfection of PEFs with exogenous DNA is essential for producing genetically modified (GM; transgenic or knockout) pigs via SCNT. In this case, selectable markers are strictly required selecting and enriching stably transfected cells. The most frequently used selective drug for this purpose is a neomycin analogue (G418/geneticin); neo has been widely used as a selectable marker gene in the genomic manipulation of pigs. However, little is known about optimal concentrations of other selection drugs. This often hampers functional analysis of the porcine genome and development of individual GM pigs. This study explores the optimal concentrations of selective drugs, other than neomycin, that can be used for the selection of transfected PEFs. Porcine embryonic fibroblasts were incubated in media containing different concentrations of drugs for up to 10 days, to determine the optimal drug concentrations fatal for PEFs. The following concentrations were found to be optimal selective concentrations for use with PEFs: G418/geneticin, 400 µg/ml; blasticidin S, 8 µg/ml; hygromycin B, 40 µg/ml; puromycin, 2 µg/ml; and zeocin, 800 µg/ml. Repeated transfections with plasmids carrying selectable markers resulted in the generation of multidrug-resistant swine transfectants. Furthermore, these markers were found to be independent. The present information will be useful for the production of SCNT-mediated GM piglets that express multiple transgenes.


Asunto(s)
Animales Modificados Genéticamente/embriología , Fibroblastos/ultraestructura , Técnicas de Transferencia Nuclear/veterinaria , Porcinos Enanos/embriología , Acetiltransferasas/genética , Animales , Bleomicina/farmacología , Muerte Celular/efectos de los fármacos , ADN/análisis , Resistencia a Medicamentos/genética , Femenino , Fibroblastos/efectos de los fármacos , Marcadores Genéticos , Gentamicinas/farmacología , Edad Gestacional , Proteínas Fluorescentes Verdes/genética , Higromicina B/farmacología , Nucleósidos/farmacología , Puromicina/farmacología , Porcinos , Porcinos Enanos/genética , Transfección , Transgenes/genética
9.
Reprod Domest Anim ; 46(5): 911-6, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21906188

RESUMEN

Porcine embryonic fibroblasts (PEFs) have been used extensively as donor nuclei for the production of cloned pigs via somatic cell nuclear transfer (SCNT). Somatic cell nuclear transfer of gene-targeted PEFs has been the only way to produce gene-targeted pigs, given the lack of germ-line-competent porcine embryonic stem cells. Unlike other primary-cultured cells, such as murine embryonic fibroblasts, a single porcine PEF is unable to proliferate under normal conditions in which a certain number of PEFs (likely over 100) can grow normally. This limitation greatly hampers re-cloning of gene-modified PEFs, which is required for SCNT. Herein, we demonstrate the cultivation of a single PEF transfectant carrying the pEGFP-N1 plasmid with intact normal PEFs (>100) in a Terasaki microtest plate, which resulted in stimulation of the growth of the former cell (doubling time = 2.6 days). In contrast, when a single cell was cultured, it could typically divide only once and never divided more than twice. When a single transfectant was seeded in a well of a 96-well plate together with 5 × 10(4) untransfected PEFs and was subsequently selected in the presence of G418, we obtained a pure cell population of single-cell origin. Thus, this method should be useful for the purification of target recombinant pig clones from mosaic populations that cannot be cultured as a single cell or for which suitable cell growth-promoting conditions are unclear.


Asunto(s)
Fibroblastos/citología , Fibroblastos/fisiología , Regulación de la Expresión Génica/fisiología , Proteínas Fluorescentes Verdes/metabolismo , Porcinos Enanos/embriología , Animales , Línea Celular , Proliferación Celular , Proteínas Fluorescentes Verdes/genética , Porcinos
10.
Syst Rev ; 10(1): 274, 2021 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-34696805

RESUMEN

BACKGROUND: Early pregnancy loss (unintended pregnancy loss before 20 completed weeks of gestation) is a common adverse pregnancy outcome, with previous evidence reporting incidence ranging from 10 to 30% of detected pregnancies. The objective of this systematic review and meta-analysis is to determine the incidence and range of early pregnancy loss in contemporary pregnant populations based on studies with good internal and external validity. Findings may be useful for clinical counseling in pre-conception and family planning settings and for people who experience early pregnancy loss. METHODS: We will search MEDLINE, EMBASE, and CINAHL databases using combinations of medical subject headings and keywords. Peer-reviewed, full-text original research articles that meet the following criteria will be included: (1) human study; (2) study designs: controlled clinical trials or observational studies with at least 100 pregnancies in the denominator, or systematic reviews of studies using these designs; (3) conducted in high-income countries; (4) reporting early pregnancy loss incidence, defined as unintended early pregnancy loss occurring prior to 20 weeks' gestation expressed as the number of losses among all pregnancies in the study period; (5) among a contemporary (1990 or later) general population of pregnancies; and (6) published between January 1, 1990, and August 31, 2021. We will assess the quality of included studies according to the United States Preventive Services Task Force Criteria for Assessing Internal and External Validity of Individual Studies. If appropriate, based on methodological comparability across included studies, we will conduct meta-analyses using random effects models to estimate the pooled incidence of early pregnancy loss among all studies with both good internal and external validity, with meta-analyses stratified by study design type (survey-based or self-reported and medical record-based), by induced abortion restrictions (restricted vs. unrestricted), and by gestational age (first trimester only vs. all gestational ages before 20 weeks). DISCUSSION: This systematic review will synthesize existing evidence to calculate a current estimate of early pregnancy loss incidence and variability in reported incidence estimates in high-income settings. The findings of this review may inform updates to clinical counseling in pre-conception and family planning settings, as well as for patients experiencing early pregnancy loss. SYSTEMATIC REVIEW REGISTRATION: We have registered this review with the International Prospective Register of Systematic Reviews (PROSPERO #226267 ).


Asunto(s)
Aborto Espontáneo , Aborto Espontáneo/epidemiología , Femenino , Humanos , Incidencia , Lactante , Metaanálisis como Asunto , Embarazo , Resultado del Embarazo , Literatura de Revisión como Asunto , Revisiones Sistemáticas como Asunto , Estados Unidos
11.
Br J Cancer ; 103(2): 223-31, 2010 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-20551957

RESUMEN

BACKGROUND: Intracellular phosphoprotein activation significantly regulates cancer progression. However, the significance of circulating phosphoproteins in the blood remains unknown. We investigated the serum phosphoprotein profile involved in pancreatic cancer (PaCa) by a novel approach that comprehensively measured serum phosphoproteins levels, and clinically applied this method to the detection of PaCa. METHODS: We analysed the serum phosphoproteins that comprised cancer cellular signal pathways by comparing sera from PaCa patients and benign controls including healthy volunteers (HVs) and pancreatitis patients. RESULTS: Hierarchical clustering analysis between PaCa patients and HVs revealed differential pathway-specific profiles. In particular, the components of the extracellular signal-regulated kinase (ERK) signalling pathway were significantly increased in the sera of PaCa patients compared with HVs. The positive rate of p-ERK1/2 (82%) was found to be superior to that of CA19-9 (53%) for early stage PaCa. For the combination of these serum levels, the area under the receiver-operator characteristics curves was showing significant ability to distinguish between the two populations in independent validation set, and between cancer and non-cancer populations in another validation set. CONCLUSION: The comprehensive measurement of serum cell signal phosphoproteins is useful for the detection of PaCa. Further investigations will lead to the implementation of tailor-made molecular-targeted therapeutics.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Pancreáticas/diagnóstico , Fosfoproteínas/sangre , Transducción de Señal , Análisis por Conglomerados , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Quinasas Quinasa Quinasa PAM/metabolismo , Masculino , Neoplasias Pancreáticas/sangre , Pancreatitis/sangre , Fosforilación , Proteómica/métodos
12.
Phys Rev Lett ; 105(24): 243401, 2010 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-21231524

RESUMEN

We report here the first successful synthesis of cold antihydrogen atoms employing a cusp trap, which consists of a superconducting anti-Helmholtz coil and a stack of multiple ring electrodes. This success opens a new path to make a stringent test of the CPT symmetry via high precision microwave spectroscopy of ground-state hyperfine transitions of antihydrogen atoms.

13.
Hepatogastroenterology ; 56(89): 1-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19453018

RESUMEN

BACKGROUND/AIMS: Management of patients with recurrent intrahepatic cholangiocarcinoma (ICC) following surgical resection is difficult, and surgical resection is rarely indicated. We retrospectively reviewed patients with recurrent intrahepatic cholangiocarcinoma. METHODOLOGY: Between April 1998 and March 2007, 57 consecutive patients with ICC underwent surgical resection. Mode of recurrence and treatment of recurrent tumors, especially surgical resection for these tumors, in patients with cancer recurrence were evaluated. RESULTS: 37 (65%) patients experienced tumor recurrence. Out of these patients, 24 underwent some type of cancer-directed therapy, including 9 patients (24%) for whom surgical resection was attempted: the latter included 4 hepatic resections, 2 pulmonary resections, 2 tumor resections, and 1 gastric resection. For 6 patients with recurrent tumor in the liver or the lung, microscopic complete resection was achieved, while incomplete resection was resulted in the remaining 3 patients. No postoperative mortality was encountered. Among patients with complete resection, 3 are alive without disease 32, 39 and 77 months after the second operation, one has lived with disease for 13 months, and 2 died of disease after 22 and 26 months. No significant difference in overall survival was observed between patients undergoing primary and second surgical resections, calculated from the primary and the second operations, respectively. CONCLUSIONS: Repeated surgical resection for recurrent ICC can be performed with acceptable morbidity, and affords selected patients a chance for long-term survival.


Asunto(s)
Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos , Colangiocarcinoma/cirugía , Recurrencia Local de Neoplasia/cirugía , Anciano , Neoplasias de los Conductos Biliares/patología , Distribución de Chi-Cuadrado , Colangiocarcinoma/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Pronóstico , Recurrencia , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
14.
Br J Cancer ; 99(2): 305-13, 2008 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-18594526

RESUMEN

Pancreatic cancer has one of the highest mortalities among all malignancies and there is an urgent need for new therapy. This might be achieved by resolving the detailed biological mechanism, and in this study we examined how pancreatic cancer cells develop aggressive properties by focusing on signalling through the fibroblast growth factor (FGF)10 and FGF receptor (FGFR)2, which play important roles in pancreatic organogenesis. Immunostaining of pancreatic cancer tissues showed that FGFR2 was expressed in cancer cells, whereas FGF10 was expressed in stromal cells surrounding the cancer cells. Patients with high FGFR2 expression in cancer cells had a shorter survival time compared to those with low FGFR2 expression. Fibroblast growth factor 10 induced cell migration and invasion of CFPAC-1 and AsPC-1 pancreatic cancer cells through interaction with FGFR2-IIIb, a specific isoform of FGFR2. Fibroblast growth factor 10 also induced expression of mRNA for membrane type 1-matrix metalloproteinase (MT1-MMP) and transforming growth factor (TGF)-beta1, and increased secretion of TGF-beta1 protein from these cell lines. These data indicate that stromal FGF10 induces migration and invasion in pancreatic cancer cells through interaction with FGFR2, resulting in a poor prognosis. This suggests that FGF10/FGFR2 signalling is a promising target for new molecular therapy against pancreatic cancer.


Asunto(s)
Carcinoma Ductal Pancreático/patología , Movimiento Celular/fisiología , Factor 10 de Crecimiento de Fibroblastos/metabolismo , Neoplasias Pancreáticas/patología , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/metabolismo , Anciano , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Línea Celular Tumoral , Femenino , Factor 10 de Crecimiento de Fibroblastos/biosíntesis , Factor 10 de Crecimiento de Fibroblastos/farmacología , Humanos , Inmunohistoquímica , Masculino , Metaloproteinasa 14 de la Matriz/biosíntesis , Metaloproteinasa 14 de la Matriz/genética , Persona de Mediana Edad , Invasividad Neoplásica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Pronóstico , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/biosíntesis , Proteínas Recombinantes/farmacología , Transducción de Señal , Células del Estroma/metabolismo , Células del Estroma/patología , Factor de Crecimiento Transformador beta1/biosíntesis , Factor de Crecimiento Transformador beta1/genética , Regulación hacia Arriba/efectos de los fármacos
15.
Bone ; 43(1): 209-213, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18482878

RESUMEN

Mandibular cortical erosion detected on dental panoramic radiographs (DPRs) may be useful for identifying women with osteoporosis, but little is known about the variation in diagnostic efficacy of observers worldwide. The purpose of this study was to measure the accuracy in identifying women at risk for osteoporosis in a worldwide group of observers using DPRs. We constructed a website that included background information about osteoporosis screening and instructions regarding the interpretation of mandibular cortical erosion. DPRs of 100 Japanese postmenopausal women aged 50 years or older who had completed skeletal bone mineral measurements by dual energy X-ray absorptiometry were digitized at 300 dpi. These were displayed on the website and used for the evaluation of diagnostic efficacy. Sixty observers aged 25 to 66 years recruited from 16 countries participated in this study. These observers classified cortical erosion into one of three groups (none, mild to moderate, and severe) on the website via the Internet, twice with an approximately 2-week interval. The diagnostic efficacy of the Osteoporosis Self-Assessment Tool (OST), a simple clinical decision rule based on age and weight, was also calculated and compared with that of cortical erosion. The overall mean sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the 60 observers in identifying women with osteoporosis by cortical erosion on DPRs were 82.5, 46.2, 46.7, and 84.0%, respectively. Those same values by the OST index were 82.9, 43.1, 43.9, and 82.4%, respectively. The intra-observer agreement in classifying cortical erosion on DPRs was sufficient (weighted kappa values>0.6) in 36 (60%) observers. This was significantly increased in observers who specialized in oral radiology (P<0.05). In the 36 observers with sufficient intra-observer agreement, the overall mean sensitivity, specificity, PPV, and NPV in identifying women with osteoporosis by any cortical erosion were 83.5, 48.7, 48.3, and 85.7%, respectively. The mean PPV and NPV were significantly higher in the 36 observers with sufficient intra-observer agreement than in the 24 observers with insufficient intra-observer agreement. Our results reconfirm the efficacy of cortical erosion findings in identifying postmenopausal women at risk for osteoporosis, among observers with sufficient intra-observer agreement. Information gathered from radiographic examination is at least as useful as that gathered from the OST index.


Asunto(s)
Servicios de Salud Dental , Tamizaje Masivo/métodos , Osteoporosis/diagnóstico por imagen , Radiografía Panorámica , Absorciometría de Fotón , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , Femenino , Humanos , Persona de Mediana Edad , Posmenopausia
16.
Transplant Proc ; 50(1): 168-174, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29407304

RESUMEN

BACKGROUND: There has been no public structured training program for transplant surgeons in Japan. However, such a program is crucial for optimizing liver transplant surgery and training young professionals in liver transplant surgery. A comprehensive training program was recently developed and the underlying concepts, structure and curriculum, and results of this program are described here. METHODS: We developed a 3-year training program in 2014 called the Six National University Consortium in Liver Transplant Professionals Training (SNUC-LT) program supported by the Ministry of Education, Culture, Sports, Science, and Technology. This program is based on strong cooperation among 6 national universities (Kumamoto, Okayama, Nagasaki, Kanazawa, Niigata, and Chiba Universities). The program includes various courses to help trainees learn transplant theory and practice as well as to teach surgical skills required to safely perform transplant surgery. RESULTS: Three trainees completed the specially designed 3-year curriculum. They attended lectures on transplant theory for an average of 59 hours and participated in an average of 44 liver transplant surgeries and 51 liver resections for transplant practice. Trainees from low-volume centers had sufficient opportunities to attend operations in high-volume centers because of the cooperative agreement among the universities. After finishing the program, the trainees were certified as talent-proven liver transplant surgeons. CONCLUSIONS: The SNUC-LT program is the first national program in Japan to have strong professional support. Our multicenter program enables young surgeons to have more abundant knowledge, more extensive experience, better surgical skills, and smoother communication skills in the field of liver transplantation.


Asunto(s)
Educación de Postgrado en Medicina/métodos , Trasplante de Hígado/educación , Desarrollo de Programa , Cirujanos/educación , Curriculum , Humanos , Japón , Universidades
17.
Mol Cell Biol ; 10(4): 1664-71, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2157138

RESUMEN

Ligand-induced tyrosine phosphorylation of the human colony-stimulating factor 1 receptor (CSF-1R) could involve either an intra- or intermolecular mechanism. We therefore examined the ability of a CSF-1R carboxy-terminal truncation mutant to phosphorylate a kinase-defective receptor, CSF-1R[met 616], that contains a methionine-for-lysine substitution at its ATP-binding site. By using an antipeptide serum that specifically reacts with epitopes deleted from the enzymatically competent truncation mutant, cross-phosphorylation of CSF-1R[met 616] on tyrosine was demonstrated, both in immune-complex kinase reactions and in intact cells stimulated with CSF-1. Both in vitro and in vivo, CSF-1R[met 616] was phosphorylated on tryptic peptides identical to those derived from wild-type CSF-1R, suggesting that receptor phosphorylation on tyrosine can proceed via an intermolecular interaction between receptor monomers. When expressed alone, CSF-1R[met 616] did not undergo ligand-induced down modulation, but its phosphorylation in cells coexpressing the kinase-active truncation mutant accelerated its degradation.


Asunto(s)
Factores Estimulantes de Colonias/metabolismo , Receptores de Superficie Celular/metabolismo , Aminoácidos/análisis , Animales , Anticuerpos , Complejo Antígeno-Anticuerpo , Línea Celular , Células Cultivadas , Factores Estimulantes de Colonias/farmacología , Ligandos , Mapeo Peptídico , Fosfopéptidos/aislamiento & purificación , Fosforilación , Receptores de Superficie Celular/efectos de los fármacos , Receptores de Superficie Celular/genética , Receptores del Factor Estimulante de Colonias , Transfección , Tirosina
18.
Cancer Res ; 46(5): 2507-10, 1986 May.
Artículo en Inglés | MEDLINE | ID: mdl-2421879

RESUMEN

Intact K562 human leukemic cells showed bright membrane immunofluorescence after staining with monoclonal antibody to O-phosphotyrosine (PTyr). Up to 60% of the cells were lysed with mouse, rabbit, or human antibodies to PTyr by a complement-mediated mechanism. A new method has been developed for identifying proteins that have PTyr residues on the outside of cell membrane, and at least two species of PTyr-containing proteins with the molecular weights of 45,000 and 36,000 were identified as the most probable candidates of the antigens responsible for the membrane fluorescence and cell lysis.


Asunto(s)
Leucemia/inmunología , Proteínas de Neoplasias/inmunología , Fosfoproteínas/inmunología , Tirosina/análogos & derivados , Anticuerpos Monoclonales/inmunología , Línea Celular , Membrana Celular/inmunología , Proteínas del Sistema Complemento/inmunología , Citotoxicidad Inmunológica , Técnica del Anticuerpo Fluorescente , Humanos , Proteínas de la Membrana/inmunología , Peso Molecular , Fosfotirosina , Tirosina/inmunología
19.
Cancer Res ; 52(23): 6463-70, 1992 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-1330294

RESUMEN

Tumor-associated antigens that are expressed in tumor cells of cattle with enzootic bovine leukosis (EBL) were analyzed previously by use of 13 monoclonal antibodies. We biochemically identified one of the tumor-associated antigens, which is recognized by the c143 monoclonal antibody, as two glycoproteins, each having an apparent molecular weight of 32,000 or 34,000. These glycoproteins were found in the plasma membrane of peripheral blood lymphocytes of both bovine leukemia virus (BLV)-free normal and BLV-infected cattle. With the progression of EBL, the proportion and the absolute number of cells positive for the tumor-associated antigen increased. Moreover, the level of the M(r) 34,000 component, which was susceptible to cell-surface labeling, increased over the level of the M(r) 32,000 component. Partial proteolytic peptide mapping with V8 protease and deglycosylation analysis revealed that the two glycoproteins most likely have an identical M(r) 30,000 polypeptide portion but have different N-linked oligosaccharide portions. Both glycoproteins were found to be phosphorylated at serine residue(s) in EBL-derived B-lymphoid cell lines and in tumor cells and peripheral blood lymphocytes from cattle with EBL, but not in peripheral blood lymphocytes from BLV-free normal cattle and BLV-infected cattle without any evidence of tumor, suggesting that the phosphorylation of these glycoproteins is related to the transformed state of the BLV-infected B-lymphoid cells.


Asunto(s)
Antígenos de Neoplasias/análisis , Leucosis Bovina Enzoótica/inmunología , Virus de la Leucemia Bovina , Linfocitos/inmunología , Linfoma no Hodgkin/inmunología , Glicoproteínas de Membrana/análisis , Animales , Anticuerpos Monoclonales , Antígenos de Neoplasias/química , Bovinos , Electroforesis en Gel de Poliacrilamida , Leucosis Bovina Enzoótica/diagnóstico , Citometría de Flujo , Glicosilación , Linfoma no Hodgkin/diagnóstico , Glicoproteínas de Membrana/química , Peso Molecular , Mapeo Peptídico , Fosforilación , Ensayo de Radioinmunoprecipitación
20.
Clin Cancer Res ; 3(4): 495-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9815711

RESUMEN

To evaluate the correlation between serum levels of sialyl Lewis X-i antigen and distant metastasis and survival in patients with non-small cell lung cancer (NSCLC), we measured the serum levels of the tumor marker in 371 patients with untreated NSCLC. The sialyl Lewis X-i antigen level was measured using a RIA kit. In patients with adenocarcinoma or other NSCLC subtypes, there was a correlation between serum sialyl Lewis X-i antigen and stage of the disease (P = 0.0001 and P = 0.0015, respectively). Levels of the marker varied significantly depending on the number of metastatic organs in adenocarcinoma (P = 0.0089) and in other NSCLC subtypes (P = 0.002). Univariate analysis showed that survival of NSCLC patients with high (more than 100 units/ml) sialyl Lewis X-i antigen levels was significantly poorer than that of patients with low antigen levels (P = 0.0001). Multivariate analysis using Cox's proportional hazard model showed that high sialyl Lewis X-i antigen levels correlated significantly with poor survival (P = 0.004). Our data suggest that a high serum level of sialyl Lewis X-i antigen seems to be an indicator of the presence of metastasis and might indicate the need for a careful investigation of all putative metastatic sites. The serum levels of sialyl Lewis X-i antigen may reflect the extension of metastasis and would be helpful in considering treatment options.


Asunto(s)
Biomarcadores de Tumor/sangre , Carcinoma de Pulmón de Células no Pequeñas/sangre , Neoplasias Pulmonares/sangre , Oligosacáridos/sangre , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Femenino , Humanos , Antígenos del Grupo Sanguíneo de Lewis/sangre , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Antígeno Sialil Lewis X , Análisis de Supervivencia , Factores de Tiempo
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