RESUMEN
Semaphorins, a family of secreted and membrane-bound proteins, are known to function as repulsive axon guidance molecules. Sema4D, a class 4 transmembrane-type semaphorin, is expressed by oligodendrocytes in the central nervous system, but its role is unknown. In this study, the effects of Sema4D deficiency on oligodendrocytes were studied in intact and ischemic brains of adult mice. As observed in previous studies, Sema4D marked by beta-galactosidase in Sema4D mutant mice was localized exclusively on myelin-associated glycoprotein (MAG)-positive oligodendrocytes but not on NG2-positive oligodendrocyte progenitor cells (OPCs). Although there was no difference in the number of the latter cells between Sema4D-deficient and wild-type mice, the number of MAG-positive cells was significantly increased in the cerebral cortex of both nonischemic and postischemic brains of Sema4D-deficient mice. Cell proliferation, observed by using bromodeoxyuridine incorporation, was evident in the MAG-positive cells that developed after cerebral ischemia. These data indicate that Sema4D is involved in oligodendrogenesis during development and during recovery from ischemic injury.
Asunto(s)
Corteza Cerebral/patología , Infarto de la Arteria Cerebral Media/patología , Ataque Isquémico Transitorio/patología , Oligodendroglía/citología , Daño por Reperfusión/patología , Semaforinas/fisiología , Animales , Recuento de Células , Diferenciación Celular , División Celular , Femenino , Infarto de la Arteria Cerebral Media/metabolismo , Ataque Isquémico Transitorio/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Vaina de Mielina/metabolismo , Oligodendroglía/patología , Semaforinas/deficiencia , Semaforinas/genéticaRESUMEN
The implementation of efficient technologies for the production of recombinant mammalian membrane receptors is an outstanding challenge in understanding receptor-ligand actions and the development of therapeutic antibodies. In order to improve the solubility of recombinant extracellular domains of human membrane receptors expressed in Escherichia coli, proteins were synthesized by an E. coli in vitro translation system supplemented with bacterial molecular chaperones, such as GroEL-GroES (GroEL/ES), Trigger factor (TF), a DnaK-DnaJ-GrpE chaperone system (DnaKJE), and/or a heat shock protein Hsp100, ClpB. The following three proteins that are prone to aggregation were examined: the extracellular domain (ECD) or the second immunoglobulin-like domain (IgII) of the human neurotrophin receptor TrkC (TrkC-ECD and TrkC-IgII), and the C-type lectin carbohydrate recognition domain of the human asialoglycoprotein receptor (ASGPR HI CRD). The cooperative chaperone system including GroEL/ES, DnaKJE and ClpB had a marked effect on the solubility of TrkC-ECD and TrkC-IgII, and the GroEL/ES-DnaKJE-TF chaperone system was more effective for TrkC-IgII. The GroEL/ES-DnaKJE-TF chaperone network increased the yield of soluble ASGPR HI CRD. The present findings demonstrate that E. coli molecular chaperones are useful in improving the yield of soluble recombinant extracellular domains of human membrane receptors in an E. coli expression system.
Asunto(s)
Proteínas de Escherichia coli/metabolismo , Escherichia coli , Chaperonas Moleculares/metabolismo , Receptores de Superficie Celular/biosíntesis , Proteínas Recombinantes/biosíntesis , Sistema Libre de Células/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Humanos , Chaperonas Moleculares/genética , Estructura Terciaria de Proteína/fisiología , Proteínas Recombinantes/genética , SolubilidadRESUMEN
Although physical monitoring of space radiation has been accomplished, we aim to measure exact DNA damage as caused by space radiation. If DNA damage is caused by space radiation, we can detect DNA damage dependent on the length of the space flight periods by using post-labeling methods. To detect DNA damage caused by space radiation, we placed fixed human cervical carcinoma (HeLa) cells in the Russian Mir space station for 40 days and in an American space shuttle for 9 days. After landing, we labeled space-radiation-induced DNA strand breaks by enzymatic incorporation of [3H]-dATP with terminal deoxyribo-nucleotidyl transferase (TdT). We detected DNA damage as many grains on fixed silver emulsion resulting from beta-rays emitted from 3H-atoms in the nuclei of the cells placed in the Mir-station (J/Mir mission, STS-89), but detected hardly any in the ground control sample. In the space shuttle samples (S/MM-8), the number of cells having many grains was lower than that in the J/Mir mission samples. These results suggest that DNA damage is caused by space radiation and that it is dependent on the length of the space flight.
Asunto(s)
Radiación Cósmica/efectos adversos , Daño del ADN , ADN/efectos de la radiación , Vuelo Espacial , Células HeLa , Humanos , Federación de Rusia , Factores de Tiempo , Estados UnidosRESUMEN
Fatty acid binding proteins (FABPs) are a family of small and highly conserved lipid chaperone molecules with highly varied functions. Among them, fatty acid binding protein 4 (FABP4, also known as aP2) is highly expressed by adipocytes, macrophages and dendritic cells. Although the role of FABP4 in cancer is still unclear, it has been reported to be highly expressed by human tumors such as ovarian and bladder cancers. In the present study, we investigated the expression and role of FABP4 in oral squamous cell carcinoma (SCC) and its expression in oral SCC tissues. Immunohistochemical staining revealed that FABP4 expression in the tumor tissue was much higher than that in the non-tumor area of the same specimen. In the in vitro studies, an FABP4-knockdown SCC cell line (established through FABP4-specific siRNA) showed inhibited growth, and inhibited expression and activation of mitogen-activated protein kinase (MAPK). These results indicate that expression of FABP4 plays an important role in the cell growth of oral SCC through the MAPK pathway.
Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Proliferación Celular , Proteínas de Unión a Ácidos Grasos/metabolismo , Neoplasias de la Lengua/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proteínas de Unión a Ácidos Grasos/genética , Femenino , Expresión Génica , Técnicas de Silenciamiento del Gen , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Persona de Mediana Edad , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Procesamiento Proteico-Postraduccional , Neoplasias de la Lengua/patologíaRESUMEN
As part of the GBC (Global Bioanalysis Consortium), the L3 assay format team has focused on reviewing common platforms used to support ligand binding assays in the detection of biotherapeutics. The following review is an overview of discussions and presentations from around the globe with a group of experts from different companies to allow an international harmonization of common practices and suggestions for different platforms. Some of the major platforms include Gyrolab, Erenna, RIA, AlphaLISA, Delfia, Immuno-PCR, Luminex, BIAcore, and ELISAs. The review is meant to support bioanalysts in taking decisions between different platforms depending on the needs of the analyte with a number of recommendations to help integration of platforms into a GLP environment.
Asunto(s)
Conducta Cooperativa , Guías de Práctica Clínica como Asunto , Ensayo de Inmunoadsorción Enzimática , Ligandos , Reacción en Cadena de la Polimerasa , RadioinmunoensayoRESUMEN
BACKGROUND: Oral adjuvant chemotherapy without hospitalization might reduce the physiological and psychological burden on patients if effectiveness could be guaranteed. We conducted a multicenter feasibility study using S-1, an oral derivative of 5-fluorouracil, as postoperative adjuvant chemotherapy in patients with curatively resected pathologically stage IB-IIIA non-small-cell lung cancer. PATIENTS AND METHODS: Adjuvant chemotherapy comprised 8 courses (4-week administration, 2-week withdrawal) of S-1 at 80-120 mg per day. Fifty-one patients from 7 institutions were enrolled in this pilot study, from June 2005 to March 2007. The primary end point was the completion rate of scheduled adjuvant chemotherapy. Secondary end points were the incidence and grade of adverse reactions. RESULTS: Fifty patients were eligible. The completion rate for the planned 8 courses of S-1 administration was 72.0% (36 patients). Total percentage administration amount was 71.1%. Grade 3 adverse reactions such as neutropenia (4.0%), anorexia (4.0%), thrombopenia (2.0%), anemia (2.0%), elevated total bilirubin (2.0%), hypokalemia (2.0%), nausea (2.0%), and diarrhea (2.0%) were observed, but no grade 4 adverse effects were encountered. Overall and relapse-free survival rates at 3 years were 87.7% and 69.4%, respectively. CONCLUSIONS: Postoperative 1-year administration of S-1 seems feasible as oral adjuvant chemotherapy for lung cancer. The oral formulation and low incidence of adverse reactions permit treatment on an outpatient basis. The present study would be reasonable to follow up with a properly powered phase III trial.
Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Ácido Oxónico/uso terapéutico , Tegafur/uso terapéutico , Administración Oral , Anciano , Atención Ambulatoria/métodos , Antimetabolitos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Quimioterapia Adyuvante/métodos , Terapia Combinada , Relación Dosis-Respuesta a Droga , Combinación de Medicamentos , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Ácido Oxónico/administración & dosificación , Ácido Oxónico/efectos adversos , Tegafur/administración & dosificación , Tegafur/efectos adversos , Resultado del TratamientoRESUMEN
BACKGROUND: The influence of perioperative blood transfusion on survival in squamous cell carcinoma of the head and neck is still not convincingly determined. To investigate the effect of perioperative allogeneic transfusion on survival in stage II-IV squamous cell carcinoma of the oral cavity, we studied a consecutive series of 105 patients undergoing primary tumor resection and neck dissection. METHODS: Retrospective analyses were performed using Cox proportional hazards models with 16 variables. RESULTS: Perioperative red blood cell transfusion was required in 64 (61%) patients. Multivariate analysis demonstrated that the number of positive nodes and > or =3 units of red blood cell transfusion were an independent prognostic indicators. The calculated odds ratio for death after > or =3 units transfused was 5.79 (95% confidence interval, 1.56-21.53, p <.01). CONCLUSIONS: More than 3 units of allogeneic red blood cells transfused might shorten the survival of patients with oral cavity cancer.