RESUMEN
PURPOSE: This report analyzed the outcomes of patients undergoing surgery for oral squamous cell carcinoma (OSCC) to identify the value of prognostic factors. MATERIAL AND METHODS: A total of 525 patients were studied who had undergone surgery for oral squamous cell carcinoma (OSCC) between 2000 and 2011, of whom 222 had received postoperative radiation-therapy (PORT) and or chemoradiation-therapy (PORTC). For each patient, personal data, histological findings, treatment and outcome were recorded and analyzed statistically. Survival curves were calculated using the Kaplan-Meier algorithm, and the difference in survival among subgroups was examined. RESULTS: The overall survival (OS) and disease-specific survival (DSS) 5-year survival rate in the 525 patients were respectively 71.38% and 73.18%. The differences in the overall survival and disease-specific 5-year survival were significant (p < 0.05) for age < 40 years, site of origin, N status, staging, grading, osseous medullar infiltration, and perineural invasion. In patients undergoing radiation therapy, only perineural invasion negatively influenced the survival prognosis. In 150 pT1 cases of tongue and floor-of-mouth cancer, an infiltration depth (ID) > 4 mm was statistically correlated with poorer prognosis. CONCLUSIONS: The results demonstrate an improvement in the 5-year OS and DSS rates during the past decade compared with the previous decade. Univariate analysis revealed that age, tumor staging, and lymph node involvement, extracapsular spread, grading, perineurial invasion, infiltration depth, and osseus medullary invasion were associated significantly with overall survival and disease-specific survival.
Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Quimioradioterapia , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Estadificación de Neoplasias , Pronóstico , Radioterapia Adyuvante , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
Tn5401 is a class II transposable element derived from the gram-positive bacterium Bacillus thuringiensis. The 4,837-bp transposon encodes a Tn3-like transposase (TnpA) and an integrase-like recombinase (TnpI) and is notable for its unusually long 53-bp terminal inverted repeats (TIRs). The tnpA and tnpI genes are transcribed from a common promoter, designated P(R), that is subject to negative regulation by TnpI. The TIRs of Tn5401 each contain a 38-bp sequence that can be aligned with the 38- to 40-bp TIR sequences of Tn3-like transposons and an adjacent 12-bp sequence that binds TnpI. This unique juxtaposition of TnpA and TnpI binding sites suggests that TnpI may regulate the binding or catalytic activity of TnpA. The results of the present study indicate that TnpI, in addition to functioning as a site-specific recombinase and as a transcriptional repressor, is required for TnpA binding to the TIRs of Tn5401.
Asunto(s)
Bacillus thuringiensis/genética , ADN Nucleotidiltransferasas/metabolismo , Elementos Transponibles de ADN , Recombinación Genética , Proteínas Represoras/metabolismo , Transposasas/metabolismo , Bacillus thuringiensis/metabolismo , Secuencia de Bases , Conjugación Genética , Regulación Bacteriana de la Expresión Génica , Datos de Secuencia Molecular , Mutación , Unión Proteica , Recombinasas , Resolvasas de TransposonesRESUMEN
The transformation efficiency of Bacillus thuringiensis depends upon the source of plasmid DNA. DNA isolated from B. thuringiensis, Bacillus megaterium, or a Dam- Dcm- Escherichia coli strain efficiently transformed several B. thuringiensis strains, B. thuringiensis strains were grouped according to which B. thuringiensis backgrounds were suitable sources of DNA for transformation of other B. thuringiensis strains, suggesting that B. thuringiensis strains differ in DNA modification and restriction. Efficient transformation allowed the demonstration of developmental regulation of cloned crystal protein genes in B. thuringiensis.
Asunto(s)
Bacillus thuringiensis/genética , Plásmidos , Transformación Bacteriana , Bacillus thuringiensis/crecimiento & desarrollo , Bacillus thuringiensis/fisiología , Western Blotting , Clonación Molecular , ADN Bacteriano/genética , ADN Bacteriano/metabolismo , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Metilación , Esporas BacterianasRESUMEN
Bacillus thuringiensis delta-endotoxin (crystal protein) genes are normally expressed only during sporulation. It is possible to produce crystal protein during vegetative growth by placing B. thuringiensis crystal protein genes downstream of a strong vegetative promoter. By removing a possible transcriptional terminator of the tetracycline resistance gene of pBC16 and inserting a multiple cloning site, delta-endotoxin genes can be cloned downstream from the tetracycline resistance gene promoter. This construct allows for readthrough transcription from the strong vegetative promoter. Crystal protein is then produced during vegetative growth as well as during sporulation in both B. thuringiensis and Bacillus megaterium. This construct also allows for production of delta-endotoxin in B. thuringiensis strains that do not normally produce delta-endotoxin because of a defect in sporulation.