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1.
Nutr Cancer ; 39(1): 85-95, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11588907

RESUMEN

Previously, a specific dietary supplement, selected vegetables (SV), was found to be associated with prolonged survival of stage III and IV non-small cell lung cancer (NSCLC) patients. In this study, several anticancer components in SV were measured; the anticancer activity of SV was assessed using a lung tumor model, line 1 in BALB/c mice. SV was also used in conjunction with conventional therapies by stage IIIB and IV NSCLC patients whose survival and clinical responses were evaluated. A daily portion (283 g) of SV was found to contain 63 mg of inositol hexaphosphate, 4.4 mg of daidzein, 2.6 mg of genistein, and 16 mg of coumestrol. Mouse food containing 5% SV (wt/wt) was associated with a 53-74% inhibition of tumor growth rate. Fourteen of the 18 patients who ingested SV daily for 2-46 months were included in the analyses; none showed evidence of toxicity. The first lead case remained tumor free for > 133 months; the second case showed complete regression of multiple brain lesions after using SV and radiotherapy. The median survival time of the remaining 12 patients was 33.5 months, and one-year survival was > 70%. The median survival time of the 16 "intent-to-treat" patients (including ineligible patients) was 20 months, and one-year survival was 55%. The Karnofsky performance status of eligible patients was 55 +/- 13 at entry but improved to 92 +/- 9 after use of SV for five months or longer (p < 0.01). Five patients had stable lesions for 30, 30, 20, 12, and 2 months; two of them, whose primary tumor was resected, used SV alone and demonstrated an objective response of their metastatic tumors. In addition to the two lead cases, eight patients had no new metastases after using SV. Three patients had complete regression of brain metastases after using radiotherapy and SV. In this study, daily ingestion of SV was associated with objective responses, prolonged survival, and attenuation of the normal pattern of progression of stage IIIB and IV NSCLC. A large randomized phase III clinical trial is needed to confirm the results observed in this pilot study.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/dietoterapia , Suplementos Dietéticos , Neoplasias Pulmonares/dietoterapia , Verduras/química , Adulto , Anciano , Anciano de 80 o más Años , Animales , Antineoplásicos/administración & dosificación , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Cumestrol/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Genisteína/administración & dosificación , Humanos , Isoflavonas/administración & dosificación , Estado de Ejecución de Karnofsky , Neoplasias Pulmonares/mortalidad , Masculino , Ratones , Ratones Endogámicos BALB C , Persona de Mediana Edad , Estadificación de Neoplasias , Valor Nutritivo , Ácido Fítico/administración & dosificación , Proyectos Piloto , Análisis de Supervivencia , Factores de Tiempo
2.
Nutr Cancer ; 34(1): 62-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10453443

RESUMEN

This phase I/II study evaluates the influence of selected vegetables (SV) that contain known antitumor components on the survival of stage III-IV non-small cell lung cancer (NSCLC) patients. All patients were treated with conventional therapies. SV was added to the daily diet of 5 stage I patients in the toxicity study group (TG) and 6 stage III and IV patients in the treatment group (SVG), but not to the diet of 13 stage III and IV patients in the control group (CG). Age, Karnofsky performance status (KPS), and body mass index of SVG and CG patients were comparable at entry. KPS declined in the CG patients (79 +/- 8 to 55 +/- 11) but improved in the SVG patients (75 +/- 8 to 80 +/- 13) one to three months after entry. Weight change in the CG, SVG, and TG patients was -12 +/- 5%, -2 +/- 2%, and +4 +/- 4%, respectively. The median survival time and mean survival of the CG patients were 4 and 4.8 months, but in the SVG patients they were 15.5 and 15 months (p < 0.01). No clinical signs of toxicity were found in the TG patients in the 24-month study period. Adding SV to the daily diet of NSCLC patients was found to be nontoxic and associated with improved weight maintenance, KPS, and survival of stage III and IV NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/dietoterapia , Suplementos Dietéticos , Neoplasias Pulmonares/dietoterapia , Magnoliopsida , Verduras , Adulto , Anciano , Índice de Masa Corporal , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , República Checa/epidemiología , Femenino , Humanos , Estado de Ejecución de Karnofsky , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
3.
Mutat Res ; 361(2-3): 113-20, 1996 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-8980696

RESUMEN

Asbestos fibers are widespread environmental carcinogens whose mutagenicity is now established. Nonetheless, the molecular nature of these mutations and the mechanisms by which they accelerate carcinogenesis remain poorly understood. We have assessed the ability of asbestos fibers to promote homologous recombination, a potent mechanism for generating intrachromosomal rearrangements, such as deletions, and mitotic recombination. For this, we have developed a new assay which determines the extent to which a marker gene present in DNA introduced by asbestos can recombine with homologous genes residing in a transfected cell. We have demonstrated that Calidria chrysotile fibers are mutagenic and are able to mediate transfection of molecularly marked mutant lacI genes in a manner that results in their preferential recombination with homologous wild-type genes in the transfected cell. Asbestos induced recombination events may play a significant role in asbestos mutagenesis and carcinogenesis, and promotion of recombination may underlie the well-recognized synergy of asbestos with other carcinogens.


Asunto(s)
Asbestos Serpentinas/toxicidad , Mutágenos/toxicidad , Neoplasias Experimentales/inducido químicamente , Recombinación Genética/efectos de los fármacos , Animales , Línea Celular , Fibroblastos/efectos de los fármacos , Pruebas de Mutagenicidad , Ratas
4.
Mt Sinai J Med ; 61(1): 72-6, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8183298

RESUMEN

A 42-year-old man developed a lymphoproliferative disorder and died seven weeks after undergoing liver transplantation for primary biliary cirrhosis. At autopsy, diffuse large cell lymphoma was noted to involve almost every organ. Molecular analyses of DNA isolated from an enlarged periportal lymph node indicated the presence of Epstein-Barr virus sequences and several JH immunoglobulin gene rearrangements (consistent with the presence of more than one greatly expanded clone of lymphoid cells of B-cell lineage). This case underscores the possibility of the rapid emergence of lymphoproliferative disorder related to Epstein-Barr virus early after liver transplantation, masked by a concurrent episode of acute rejection.


Asunto(s)
Trasplante de Hígado/efectos adversos , Linfoma de Células B Grandes Difuso/etiología , Adulto , ADN Viral/análisis , Resultado Fatal , Reordenamiento Génico de Linfocito B , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Cirrosis Hepática Biliar/cirugía , Trasplante de Hígado/patología , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/microbiología , Linfoma de Células B Grandes Difuso/patología , Masculino
5.
Mod Pathol ; 6(5): 575-80, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8248115

RESUMEN

Seven cases of primary lung lymphoma were analyzed for the presence of Epstein-Barr virus DNA sequences by the polymerase chain reaction. The series included: four cases of diffuse, small lymphocytic lymphoma; one case of diffuse, intermediate lymphocytic lymphoma; one case of diffuse, small cleaved cell lymphoma; and one case of large cell, immunoblastic lymphoma. The latter occurred in a patient with acquired immunodeficiency syndrome. A 200-bp sequence of the Epstein-Barr nuclear antigen 1 gene was used as a template for PCR amplification. The only tumor that contained Epstein-Barr virus sequences was the immunoblastic lymphoma. These findings support previous observations that small lymphocytic lymphomas of the lung are not related to Epstein-Barr virus infection. In contrast, some large cell lymphomas may represent Epstein-Barr-virus--associated lymphoproliferative disorders.


Asunto(s)
ADN Viral/análisis , Herpesvirus Humano 4/genética , Neoplasias Pulmonares/microbiología , Linfoma/microbiología , Reacción en Cadena de la Polimerasa , Adulto , Anciano , Secuencia de Bases , Femenino , Humanos , Inmunofenotipificación , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Linfoma/genética , Linfoma/patología , Masculino , Persona de Mediana Edad , Sondas Moleculares/genética , Datos de Secuencia Molecular
6.
Mol Immunol ; 30(12): 1069-75, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8366857

RESUMEN

Histones are frequent targets of self-reactive antibodies during autoimmune syndromes. We report the specificities and V region genes of three IgG anti-histone MAbs obtained from autoimmune mice. Each of the MAbs, named LG2-1, LG2-2 and BWA3, is directed against a different determinant located in the basic amino-terminal domain of core histones. LG2-1 reacts with a peptide from histone H3 (residues 30-45), LG2-2 recognizes the amino-terminus of H2B (residues 1-13) and BWA3 binds an epitope corresponding to a region of high sequence similarity between H2A and H4 (residues 1-20 and 1-29, respectively). The analysis of their V region sequences indicates that the H chain CDRs of these MAbs are remarkable for the presence of negatively charged amino acid residues that may play a role in the binding to cationic histones. The H chain importance in conferring reactivity to histones is corroborated by the observation that each of the VH gene segments of these MAbs is very similar to VH genes of previously described murine anti-histone antibodies.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Autoanticuerpos/inmunología , Enfermedades Autoinmunes/inmunología , Histonas/inmunología , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/genética , Especificidad de Anticuerpos , Autoanticuerpos/genética , Secuencia de Bases , Reordenamiento Génico de Cadena Pesada de Linfocito B , Reordenamiento Génico de Cadena Ligera de Linfocito B , Genes de Inmunoglobulinas , Ratones , Ratones Endogámicos , Datos de Secuencia Molecular , Proteínas Nucleares/inmunología , Péptidos/inmunología
7.
Environ Res ; 62(1): 28-42, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8325264

RESUMEN

Several different asbestos fiber types mediate transfection of human mesothelial cells by exogenous DNA. We have employed the human MeT-5A mesothelial cell line, which allows the use of DNA replication as an assay for entry of DNA when plasmids bearing the SV40 origin of replication are used for transfection. We find that Canadian chrysotile, Calidria chrysotile, amosite, and crocidolite are each capable of introducing plasmid pSVod DNA into MeT-5A cells followed by subsequent replication of a fraction of the plasmid DNA. A significant fraction of the input plasmid DNA associated with the cells in the presence of asbestos is fragmented, and this fragmentation is particularly evident with crocidolite. Each of the fiber types is highly cytotoxic for the MeT-5A cells, and these cells actively accumulate the added fibers from the surrounding environment as visualized by phase-contrast microscopy. MeT-5A cells were transfected at higher efficiency with calcium phosphate than were several other primate cell lines. Calcium phosphate, however, did not induce fragmentation of the input plasmid DNA. Compared with several different mineral agents, including glass fibers, kaolin, and talc, Calidria chrysotile fibers were most effective at mediating transfection of the MeT-5A cells. Results provide a mechanism by which transfection can contribute to mutagenicity of asbestos fibers and indicate that this mechanism can operate in human mesothelial cells.


Asunto(s)
Amianto/toxicidad , Epitelio/efectos de los fármacos , Transfección , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , ADN/análisis , ADN/genética , Replicación del ADN , Células Epiteliales , Humanos
8.
Am J Surg ; 164(1): 13-7, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1626600

RESUMEN

Fifty-two patients with ulcerative colitis and colorectal cancer undergoing colectomy at the Mount Sinai Hospital between 1973 and 1988 were studied retrospectively to determine the correlation of age, sex, duration of colitis, tumor location, number of cancers, tumor differentiation, colloid content, presence of signet ring cells, Dukes' classification, and DNA ploidy with survival. The mean age was 45 years, with a mean duration of colitis of 21 years. Five patients (10%) had Dukes' A lesions, 17 (33%) had Dukes' B lesions, 17 (33%) had Dukes' C lesions, and 13 (25%) had distant metastases. Thirty patients (58%) had well- or moderately differentiated tumors, whereas tumors were poorly differentiated in 22 (42%). Twenty-eight patients (54%) had colloid tumors, and, in 14 (27%), signet ring cells were present. Thirty-one patients (60%) had nondiploid tumors. Actuarial analysis revealed that the 5-year survival rate was significantly worse for patients with nondiploid tumors (76% versus 32%). When stratified by stage, only patients with Dukes' C lesions showed a significant difference in survival for diploid versus nondiploid tumors. Multivariate analysis showed that the Dukes' classification was the best prognostic indicator, followed by tumor differentiation and DNA ploidy. Tumor location, colloid content, number of cancers, duration of disease, age, and sex did not correlate with the prognosis.


Asunto(s)
Adenocarcinoma/mortalidad , Colitis Ulcerosa/mortalidad , Neoplasias Colorrectales/mortalidad , Análisis Actuarial , Adenocarcinoma/epidemiología , Adenocarcinoma/patología , Factores de Edad , Colitis Ulcerosa/epidemiología , Colitis Ulcerosa/patología , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/patología , ADN de Neoplasias/análisis , Citometría de Flujo , Humanos , Metástasis de la Neoplasia , Estadificación de Neoplasias , Ciudad de Nueva York/epidemiología , Ploidias , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores Sexuales
9.
Dis Colon Rectum ; 35(5): 430-5, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1568393

RESUMEN

This study was performed to determine the correlation of tumor ras and c-myc oncogene expression with clinical and prognostic variables in patients prone to develop colorectal cancer. One hundred eighteen patients with colorectal cancer were studied; mean age was 40 years. Fifty-three were young patients (age 40 or less), 49 had ulcerative colitis, and 16 had multiple polyposis coli. Immunoperoxidase stains of paraffin-embedded cancer sections were performed for the c-myc and ras proteins. ras staining was found to correlate with Dukes stage and prognosis. Patients with tumors negative for ras protein stain had an actuarial five-year survival of 61 percent versus 44 percent for those tumors with a positive stain (P less than 0.05). This correlation was not seen with the c-myc stain. Positive ras oncogene stain appears to be a useful indicator of advanced stage and poor prognosis in colorectal cancer occurring in cancer-prone patients.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Colorrectales/genética , Genes myc , Genes ras , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anticuerpos Monoclonales , Causalidad , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Femenino , Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Adhesión en Parafina , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
11.
Dis Colon Rectum ; 34(12): 1103-8, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1659978

RESUMEN

Sixteen patients with polyposis coli and cancer were studied retrospectively to determine the incidence of DNA ploidy abnormalities in the tumors and synchronous polyps. Six patients (37 percent) had nondiploid tumors. Nondiploid tumors were more likely to be advanced and had a significantly worse prognosis (17 percent vs. 76 percent 5-year survival; P less than 0.01). Only 4 of 20 polyps studied were nondiploid. There was no association between tumor and polyp ploidy. All nondiploid polyps were found in patients with synchronous diploid cancers. Patients with nondiploid polyps were more likely to be older and have more advanced tumors than those with diploid polyps. DNA ploidy abnormalities seem to occur with the same frequency in polyposis coli as in the nonpolyposis population, and tumor ploidy correlates with prognosis.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Neoplasias Colorrectales/genética , ADN/genética , Neoplasias Primarias Múltiples/genética , Ploidias , Poliposis Adenomatosa del Colon/mortalidad , Adulto , Anciano , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Primarias Múltiples/mortalidad , Adhesión en Parafina , Pronóstico , Estudios Retrospectivos
12.
J Neurooncol ; 11(1): 71-5, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1655989

RESUMEN

We investigated the levels of anti-histone antibodies in the sera of 7 patients with subacute sensory neuropathy. IgG antibodies to histones H1 and H3 were significantly elevated in 4 of these patients. The anti-H1 antibodies reacted mainly with determinants located in the central globular and the carboxy-terminal domain of the H1 molecule. We also observed reactivity of these sera with histone H1 zero, a variant found in terminally-differentiated cells such as neurons. This study suggests a potential for histones to serve as autoantigens in humorally-mediated paraneoplastic diseases.


Asunto(s)
Autoanticuerpos/análisis , Histonas/inmunología , Inmunoglobulina G/análisis , Inmunoglobulina M/análisis , Síndromes Paraneoplásicos/inmunología , Enfermedades del Sistema Nervioso Periférico/inmunología , Especificidad de Anticuerpos , Química Encefálica , Ensayo de Inmunoadsorción Enzimática , Histonas/análisis , Humanos , Valores de Referencia
13.
Mt Sinai J Med ; 57(3): 165-8, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2164643

RESUMEN

Primary hepatocellular carcinoma, one of the most common malignancies in the world, develops in chronic liver diseases of different etiologies. Hepatitis B and non-A, non-B infections, alcoholic cirrhosis, hemochromatosis, contamination with aflatoxins, and oral contraceptives are just a few of the conditions that have been associated with this carcinoma. To our knowledge, few cases of autoimmune chronic active hepatitis and hepatocellular carcinoma have been reported in the literature. We describe a patient who developed hepatocellular carcinoma 21 years after the onset of the autoimmune hepatitis.


Asunto(s)
Enfermedades Autoinmunes/complicaciones , Carcinoma Hepatocelular/complicaciones , Hepatitis Crónica/complicaciones , Neoplasias Hepáticas/complicaciones , Enfermedades Autoinmunes/patología , Carcinoma Hepatocelular/patología , Femenino , Hepatitis Crónica/patología , Humanos , Hígado/patología , Neoplasias Hepáticas/patología , Persona de Mediana Edad
14.
Pediatr Dermatol ; 7(1): 42-7, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1692995

RESUMEN

Lymphomatoid papulosis (LyP) is rarely seen in children. We report a case of LyP in a 4-year-old boy in whom immunopathologic studies demonstrated T cell antigen deletions. In contrast to all but two previous reports, a T suppressor (CD-8) phenotype was predominant. Southern blot analysis of DNA isolated from a typical skin lesion indicated a clonal rearrangement of the T cell receptor beta gene. Because of a 10% frequency of malignant lymphomas in patients with LyP, long-term observation is crucial, especially in children. We recommend routine clonal rearrangement studies for aid in diagnosis and follow-up, and as possible prognostic indicators in children with this condition.


Asunto(s)
Epítopos/inmunología , Reordenamiento Génico de Linfocito T , Enfermedades de la Piel/inmunología , Linfocitos T/inmunología , Antígenos CD/inmunología , Southern Blotting , Niño , Preescolar , Células Clonales , Femenino , Humanos , Lactante , Masculino , Receptores de Antígenos de Linfocitos T/genética , Enfermedades de la Piel/genética , Enfermedades de la Piel/patología
15.
Am J Surg ; 159(2): 199-202; discussion 202-3, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2301713

RESUMEN

Several studies have shown that the presence of DNA content abnormalities, measured by flow cytometry, may correlate with a poor prognosis in a variety of cancers. The predictive value of DNA content in patients with small rectal cancers has not been well determined. Thirty-nine patients with primary rectal adenocarcinoma smaller than 3 cm were studied in a comparison of DNA content with established prognostic variables. The following covariates were evaluated for their prognostic value: sex, age, tumor size, location, distal margin, Dukes' classification, tumor differentiation, and DNA content. DNA content was assessed by flow cytometric analysis, and each tumor was categorized as diploid or nondiploid. Of the parameters studied, Dukes' classification and tumor DNA content were found to be independent prognostic indicators. Determination of DNA content seems to provide additional useful prognostic information in patients with small rectal tumors.


Asunto(s)
Adenocarcinoma/análisis , ADN de Neoplasias/análisis , Neoplasias del Recto/análisis , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Aneuploidia , Diploidia , Femenino , Citometría de Flujo , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias del Recto/mortalidad , Neoplasias del Recto/patología , Tasa de Supervivencia
16.
Ann Surg ; 210(6): 792-5, 1989 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2589893

RESUMEN

Several studies have shown that the presence of DNA ploidy abnormalities, measured by flow cytometry, may correlate with a poor prognosis in a variety of cancers. The predictive value of these DNA abnormalities in young patients with colorectal cancer has not been well studied. Fifty patients aged 40 years and younger with colorectal adenocarcinoma were studied to determine the correlation of tumor DNA abnormalities with survival. DNA content was determined by flow cytometric analysis and each tumor was categorized as diploid or nondiploid. Of the parameters studied, Dukes' classification and tumor DNA ploidy were found to be significant prognostic indicators. Determination of DNA content seems to provide additional useful prognostic information in young patients with colorectal cancer.


Asunto(s)
Adenocarcinoma/genética , Neoplasias Colorrectales/genética , ADN de Neoplasias , Adenocarcinoma/mortalidad , Adulto , Neoplasias Colorrectales/mortalidad , Femenino , Humanos , Masculino , Ploidias , Pronóstico
17.
Proc Natl Acad Sci U S A ; 85(20): 7670-4, 1988 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2845418

RESUMEN

We have tested the ability of chrysotile asbestos fibers to introduce plasmid DNA into monkey COS-7 cells and the ability of this DNA to function in both replication and gene expression. Chrysotile fibers are at least as effective as calcium phosphate in standard transfection assays at optimal ratios of asbestos to DNA. After transfection with chrysotile, a minor percentage of introduced plasmid DNA bearing a simian virus 40 origin of replication replicates after 24 hr. Fragmentation of entering DNA is more prominent with asbestos than with calcium phosphate, and after 72 hr most DNA introduced by asbestos is associated with chromosomal DNA. Cells transfected with plasmid p11-4, bearing the p53 protooncogene, express this gene. Cells transfected with pSV2-neo express a gene conferring resistance of antibiotic G418, allowing isolation of colonies of transformed cells after 18 days. The introduction of exogenous DNA into eukaryotic cells could cause mutations in several ways and thus contribute to asbestos-induced oncogenesis.


Asunto(s)
Amianto/metabolismo , ADN/metabolismo , Vectores Genéticos , Plásmidos , Transfección , Animales , Asbestos Serpentinas , Línea Celular , ADN/biosíntesis , ADN/ultraestructura , Replicación del ADN , Regulación de la Expresión Génica , Microscopía Electrónica , Hibridación de Ácido Nucleico , Oncogenes
20.
Fed Proc ; 45: 1849, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-30260340

RESUMEN

OUR FINDING THAT DNA BINDS TIGHTLY TO THE SURFACE OF CHRYSOTILE FIBERS (3MGO, 2SIO2, 2H2O) PROMPTED US TO TEST THE ABILITY OF THESE FIBERS TO ACT AS TRANSFECTION VEHICLES FOR THE UPTAKE OF PSV2-NEO DNA INTO MONKEY COS-7 CELLS. CELL MONOLAYERS (3 X 10(5) CELLS) WERE TRANSFECTED WITH PSV2-NEO DNA AS FOLLOWS: A) COPRECIPITATED WITH CALCIUM PHOSPHATE; B) ADSORBED TO 250 UG OF SONICATED CHRYSOTILE FIBERS (UICC SAMPLE AB "CANADIAN CHRYSOTILE"); OR C) IN BUFFERED SALINE. MICROSCOPY REVEALED CELLULAR UPTAKE OF CHRYSOTILE FIBERS OF 2-5 U LENGTH AND CONTACT OF THESE FIBERS WITH NUCLEI. CELLS WERE GROWN FOR 3 DAYS PRIOR TO ADDING ANTIBIOTIC G418 (400 UG/ML). AFTER 2 WEEKS, CULTURES WERE EXAMINED TO DETERMINE NUMBER OF G418-RESISTANT COLONIES OF 50 OR MORE CELLS. NO ANTIBIOTIC-RESISTANT COLONIES WERE OBSERVED IN CONTROL CULTURES TRANSFECTED WITH PSV2-NEO DNA IN SALINE ALONE. IN THE PRESENCE OF CHRYSOTILE FIBERS, TRANSFECTION FREQUENCY AVERAGED 0.7 X 10(-4), A VALUE APPROXIMATELY 1/3 THAT OBTAINED WITH CALCIUM PHOSPHATE. CHRYSOTILE FIBERS DID NOT TRANSFORM COS-7 CELLS TO G418 RESISTANCE IN ABSENCE OF PSV2-NEO DNA. FURTHER EXPERIMENTS DEAL WITH OPTIMIZING DNA UPTAKE AND EXAMINING THE FATE OF TRANSFECTED VECTOR DNA. THESE DATA SUGGEST THAT DNA UPTAKE MAY CONTRIBUTE TO THE CYTOTOXIC OR ONCOGENIC EFFECTS OF ASBESTOS FIBERS.

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