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1.
Science ; 190(4210): 152-4, 1975 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-1166304

RESUMO

Hairless albino mice with squamous cell carcinoma were exposed to a mixture of 2.5 percent oxygen and 97.5 percent hydrogen at a total pressure of 8 atmospheres for periods up to 2 weeks in order to see if a free radical decay catalyzer, such as hydrogen, would cause a regression of the skin tumors. Marked aggression of the tumors was found, leading to the possibility that hyperbaric hydrogen therapy might also prove to be of significance in the treatment of other types of cancer.


Assuntos
Carcinoma de Células Escamosas/terapia , Hidrogênio/uso terapêutico , Neoplasias Cutâneas/terapia , Animais , Câmaras de Exposição Atmosférica , Pressão Atmosférica , Radicais Livres , Camundongos , Neoplasias Experimentais/terapia
2.
J AOAC Int ; 101(3): 831-842, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29021006

RESUMO

Single- and multilaboratory testing data have provided systematic scientific evidence that a simple, selective, accurate, and precise method can be used as a potential candidate reference method for dispute resolution in determining total biotin in all forms of infant, adult, and/or pediatric formula. Using LC coupled with immunoaffinity column cleanup extraction, the method fully meets the intended purpose and applicability statement in AOAC Standard Method Performance Requirement 2014.005. The method was applied to a cross-section of infant formula and adult nutritional matrixes, and acceptable precision and accuracy were established. The analytical platform is inexpensive, and the method can be used in almost any laboratory worldwide with basic facilities. The immunoaffinity column cleanup extraction is the key step to successful analysis.


Assuntos
Biotina/análise , Cromatografia de Afinidade/métodos , Cromatografia Líquida/métodos , Fórmulas Infantis/análise , Adulto , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Lisina/análogos & derivados , Lisina/análise , Reprodutibilidade dos Testes
3.
Cancer Res ; 55(12): 2576-82, 1995 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-7780971

RESUMO

bcl-x is a new member of the bcl-2 gene family and is highly expressed in neural tissues. The present study was designed to determine the expression of the bcl-x gene products in neuroblastoma (NB) and their role in the modulation of chemotherapy-induced apoptosis. Twenty-seven NB cell lines were screened by quantitative immunoprecipitation for Bcl-xL, Bcl-xS, and Bcl-2 expression. None of the cell lines expressed Bcl-xS. Twenty-four of 27 (88%) of the NB cell lines expressed Bcl-xL and 21 of 27 (78%) were positive for Bcl-2. The level of Bcl-xL and Bcl-2 expression was variable among the lines analyzed. Bcl-2 expression was restricted to cells of chromaffin lineage, whereas Bcl-xL was seen in both chromaffin and nonchromaffin lines. To determine whether Bcl-xL could mediate chemotherapy resistance, a NB cell line expressing negligible levels of Bcl-xL was transfected with a bcl-xL expression vector, and unique clones were generated expressing variable levels of Bcl-xL. Cells were treated either with cisplatinum (CP), 4-hydroperoxy-cyclophosphamide (4-HC), or etoposide (VP-16) to induce apoptosis, and cell viability and DNA degradation were determined. Following treatment with CP or 4-HC, Bcl-xL-expressing cells showed significantly increased viability as compared to vector-transfected controls (P < 0.005). Flow cytometric analysis of propidium iodide-stained nuclei following CP or 4-HC treatment revealed significantly increased DNA degradation in controls as compared to Bcl-xL-expressing lines (P < 0.004). DNA analysis by pulsed-field gel electrophoresis revealed high molecular weight (approximately 40 kb) DNA degradation in controls, whereas the DNA in cells expressing Bcl-xL was largely intact. In contrast to CP and 4-HC, results with VP-16 revealed a short-term delay in the onset of apoptosis in Bcl-xL-expressing cells with no long-term survival advantage. The results of these studies indicate Bcl-xL is expressed in NB cells and functions in a manner analogous to Bcl-2 by inhibiting chemotherapy-induced apoptosis.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Dano ao DNA , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/biossíntese , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/toxicidade , Ciclofosfamida/análogos & derivados , Ciclofosfamida/toxicidade , DNA de Neoplasias/análise , Etoposídeo/toxicidade , Citometria de Fluxo , Humanos , Família Multigênica , Neuroblastoma/tratamento farmacológico , Fatores de Tempo , Transfecção , Células Tumorais Cultivadas , Proteína bcl-X
4.
Cancer Res ; 54(12): 3253-9, 1994 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-8205548

RESUMO

bcl-2 is the first member of a new class of protooncogenes the products of which inhibit programmed cell death (PCD) or apoptosis. We have previously determined that Bcl-2 is expressed in a significant percentage of untreated primary neuroblastoma (NBL) tumors. In these specimens Bcl-2 expression correlated with other markers of poor prognosis suggesting a role for Bcl-2 in the malignant behavior of NBL tumor cells. To investigate this possibility, a Bcl-2-negative human NBL cell line (Shep-1) was transfected with a bcl-2 expression vector (pSFFVneo-bcl-2). Multiple unique clones were isolated which showed variable levels of Bcl-2 protein by quantitative immunoprecipitation. Vector-transfected controls were generated simultaneously. Clones expressing high levels of Bcl-2 were resistant to cisplatin- and etoposide-induced cytotoxicity in a dose-dependent manner. Analysis of propidium iodide-stained nuclei by flow cytometry after cisplatin or etoposide treatment revealed marked DNA degradation in vector-transfected controls whereas bcl-2 transfectants showed a dose-dependent inhibition of DNA degradation. Analysis by pulsed-field gel electrophoresis revealed relatively large fragment DNA degradation (approximately 50 kilobases) in the absence of internucleosomal degradation in vector-transfected control cells treated with either cisplatin or etoposide. In contrast, Bcl-2-expressing cells showed significantly less DNA degradation at all time points. These single gene transfection experiments have revealed that expression of Bcl-2 renders specific NBL cells resistant to chemotherapy-induced PCD and support the hypothesis that Bcl-2 enhances the malignant phenotype of NBL by promoting tumor resistance to chemotherapy agents.


Assuntos
Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Etoposídeo/farmacologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas/fisiologia , Apoptose/fisiologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Resistência a Medicamentos , Citometria de Fluxo , Expressão Gênica , Humanos , Neuroblastoma/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2 , Células Tumorais Cultivadas/efeitos dos fármacos
5.
Cancer Res ; 56(24): 5734-40, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8971184

RESUMO

bcl-x is a member of the bcl-2 family of genes and by alternative splicing gives rise to two distinct mRNAs: bcl-xL and bcl-xS. We have previously investigated the expression of Bcl-x in neuroblastoma (NB) cell lines and have shown that Bcl-xL is expressed and functions to inhibit chemotherapy-induced apoptosis. However, none of the NB cell lines expressed Bcl-xS. The aim of the present study was to determine the effects of Bcl-xS expression on the viability of NB cells. A panel of NB cell lines (CHP-382, GOTO, SHEP-1, SHSY-5Y, and GI-CA-N) were infected with either a bcl-xS adenovirus (pAdRSV-bcl-xS) or a control virus (pAdRSV-lac-z). NB cells showed loss of viability with both viruses, although the bcl-xS virus was most toxic. Importantly, infection with the bcl-xS adenovirus resulted in rapid loss of cell viability, DNA fragmentation, and morphological features of apoptosis even in NB cells transfected to overexpress Bcl-2 and Bcl-xL. These findings suggest that deregulated expression of Bcl-xS using an adenovirus may provide a novel mechanism for initiating cell death in tumors that express Bcl-2 or Bcl-xL.


Assuntos
Apoptose/genética , Genes bcl-2/genética , Neuroblastoma/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas/genética , Adenoviridae/genética , Fragmentação do DNA , DNA de Neoplasias/genética , Vetores Genéticos/genética , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas/metabolismo , Transfecção , Células Tumorais Cultivadas , Proteína bcl-X
6.
J Nucl Med ; 37(1): 16-21, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8543986

RESUMO

UNLABELLED: The goals of this investigation were to characterize the uptake of 11C-hydroxyephedrine (HED) in neuroblastoma and to determine the feasibility and potential advantages of utilizing this compound as a tumor imaging agent. METHODS: Seven patients with known or subsequently proven neuroblastoma were studied. Each patient underwent PET scanning with 11C-HED. Six of seven patients underwent scintigraphy with [123I]meta-iodobenzylguanidine (MIBG), and two patients were also studied with [18F]FDG PET. For six patients, CT or MR images were available for comparison. RESULTS: Neuroblastomas were located by PET scanning with 11C-HED in all seven patients. The uptake of HED into neuroblastomas was rapid; tumors were evident on images within 5 min postintravenous injection. Those lesions in the field of view of the PET camera were also identified on [123I]MIBG scintigraphic images. In two patients, tumor deposits in the abdomen were better visualized with MIBG scintigraphy due to relatively less hepatic accumulation of MIBG than HED. CONCLUSION: PET scanning with HED for neuroblastoma results in high quality functional images of the tumors that can be obtained within minutes following injection.


Assuntos
Efedrina/análogos & derivados , Neuroblastoma/diagnóstico por imagem , Tomografia Computadorizada de Emissão , 3-Iodobenzilguanidina , Adulto , Radioisótopos de Carbono , Criança , Pré-Escolar , Meios de Contraste , Desoxiglucose/análogos & derivados , Estudos de Viabilidade , Feminino , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Lactente , Radioisótopos do Iodo , Iodobenzenos , Masculino , Fatores de Tempo
7.
Indian J Med Res ; 90: 248-53, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2620949

RESUMO

Thirty patients of myelodysplastic syndrome (MDS) were treated over a period of 2 yr using 3 different treatment regimens. Twelve patients received hydroxyurea, 4 were given low dose cytosine arabinoside and 14 others were treated with an aggressive acute myeloid leukaemia (AML) induction regimen. A low complete remission was obtained in the first 2 groups (17 and 25% respectively), whereas 9 (64%) patients attained complete remission with the AML induction regimen. Remission in the latter group was associated with prolonged and severe pancytopenia requiring intensive support. Patients in all the 3 groups had a short duration of remission culminating in death with progressive marrow failure or evolution to AML, indicating the limitations of the current treatment strategies for MDS and highlighting the need for exploring newer therapeutic approaches.


Assuntos
Síndromes Mielodisplásicas/tratamento farmacológico , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Citarabina/uso terapêutico , Feminino , Humanos , Hidroxiureia/uso terapêutico , Masculino , Pessoa de Meia-Idade
8.
J Reprod Med ; 23(2): 49-56, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-158645

RESUMO

Controversy exists over the proper methods of sterilizing laparoscopic telescopes. An edict requiring gas sterilization rather than solution soaking of these instruments is in force in all federal hospitals. This rule has necessitated capital investments for new instruments and has led to a severe reduction in the number of cases of laparoscopy that may be scheduled in one day. Fear of contamination is based on theoretical considerations and rusn counter to the actual, observed safety record seen with laparoscopes soaked in activated glutaraldehyde between cases. In an effort to dispassionately approach this problem, cultures of the umbilical area, the laparoscope and the pelvic serosal surfaces were taken to document the type of organisms commonly encountered under clinical conditions. Cultures for aerobic and anaerobic bacteria as well as for fungi were taken after soaking the telescope in activated glutaraldehyde. The results demonstrated growth of common skin organisms even after skin preparation with povidone-iodine and ethyl alcohol. Similar organisms were recovered in some cases from the laparoscope and the pelvic surfaces. The actual degree of contamination suggested by a colony count falls well within the range of the healthy peritoneum to cope with these organisms. Recommendations for laparoscopic sterilization or disinfection are based on the results obtained.


Assuntos
Bactérias/isolamento & purificação , Laparoscópios , Esterilização/métodos , Líquido Ascítico/microbiologia , Óxido de Etileno , Glutaral , Humanos , Laparoscopia/economia , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Povidona-Iodo , Pele/microbiologia
16.
J Trop Pediatr ; 35(5): 218-20, 1989 10.
Artigo em Inglês | MEDLINE | ID: mdl-2511333

RESUMO

The efficacy of enzyme-linked immuno-assay in the detection of IgG antibody against mycobacterium tuberculosis in the cerebrospinal fluid of patients suffering from tuberculous meningitis was measured in 50 children consecutively admitted to hospital. The controls were 15 cases of tuberculosis other than of the central nervous system; 24 cases of pyogenic meningitis; 19 cases of neurologic problems but with essentially normal cerebrospinal fluid. The specificity of the test ranged from 93 to 100 per cent and the sensitivity from 82 to 95 per cent.


Assuntos
Anticorpos Antibacterianos/líquido cefalorraquidiano , Países em Desenvolvimento , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/líquido cefalorraquidiano , Mycobacterium tuberculosis/imunologia , Tuberculose Meníngea/diagnóstico , Especificidade de Anticorpos , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Masculino , Tuberculose Meníngea/imunologia
17.
Am J Pathol ; 143(6): 1543-50, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8256847

RESUMO

Survival rate in neuroblastoma, a tumor of post-ganglionic sympathetic neuroblasts, correlates with disease stage, tumor histology, and N-myc gene amplification. N-myc amplification is associated with rapid tumor progression and poor survival, but is not present in all cases of poor prognosis neuroblastoma. Moreover, overexpression of N-myc is not sufficient to cause cellular transformation. These data suggest that other genetic factors are important for neuroblastoma development. We investigated the expression of the, bcl-2 proto-oncogene in untreated cases of neuroblastoma. bcl-2 is a novel proto-oncogene that promotes cell growth by inhibiting programmed cell death (apoptosis), a form of cellular demise common during normal neurogenesis. Immunocytochemical localization using a monoclonal anti-bcl-2 antibody revealed that 16 of 40 patient specimens stained positive for bcl-2. bcl-2 was strongly associated with unfavorable histology (P = 0.002) and N-myc gene amplification (P = 0.002) and marginally associated with poor stage disease (P = 0.06). A logistic regression model evaluating the simultaneous association of stage, histology, and N-myc revealed that bcl-2 was most associated with unfavorable histology and N-myc gene amplification. These results support the notion that bcl-2 may play an important role in the genesis or progression of malignant neuroblastoma.


Assuntos
Apoptose/fisiologia , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica/genética , Genes myc/genética , Neuroblastoma/genética , Neuroblastoma/patologia , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas/fisiologia , Adolescente , Western Blotting , Transformação Celular Neoplásica/patologia , Criança , Pré-Escolar , Humanos , Técnicas Imunoenzimáticas , Lactente , Recém-Nascido , Estadiamento de Neoplasias , Neuroblastoma/química , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2
19.
Radiology ; 194(2): 495-500, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7824731

RESUMO

PURPOSE: To assess the uptake of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) in common and uncommon tumors in children and to develop a method for performing positron emission tomography (PET) studies in children with malignant neoplasms. MATERIALS AND METHODS: Twenty-two pediatric patients with known or suspected malignancies (27 scans) underwent FDG PET. Tumor uptake of FDG was measured on PET scans. RESULTS: Tumor uptake of FDG was detected in 17 of 21 patients with malignant disease. Neuroblastomas and their metastases (including those that did not absorb metaiodobenzylguanidine) intensely accumulated FDG. In a patient with Ewing sarcoma, FDG PET showed two foci of metastatic disease not evident on bone scans. In two patients, PET showed that large areas of the tumor were necrotic. CONCLUSION: FDG PET is feasible, is useful in the study of tumors in children, and may provide unique, clinically important information.


Assuntos
Desoxiglucose/análogos & derivados , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada de Emissão , Adolescente , Criança , Radioisótopos de Flúor , Fluordesoxiglucose F18 , Humanos , Lactente , Linfoma/diagnóstico por imagem , Neuroblastoma/diagnóstico por imagem , Neuroblastoma/secundário , Sarcoma de Ewing/diagnóstico por imagem , Sarcoma de Ewing/secundário
20.
J Biol Chem ; 272(45): 28237-46, 1997 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-9353275

RESUMO

We recently cloned cDNAs encoding three subtypes of human alpha1-adrenergic receptors (alpha1ARs), alpha1a, alpha1b, and alpha1d (Schwinn, D. A., Johnston, G. L., Page, S. O., Mosley, M. J., Wilson, K. H., Worman, N. P., Campbell, S., Fidock, M. D., Furness, L. M., Parry-Smith, D. J., Peter, B., and Bailey, D. S. (1995) J. Pharmacol. Exp. Ther. 272, 134-142) and demonstrated predominance of alpha1aARs in many human tissues (Price, D. T., Lefkowitz, R. J., Caron, M. G., Berkowitz, D., and Schwinn, D. A. (1994) Mol. Pharmacol. 45, 171-175). Several lines of evidence indicate that alpha1aARs are important in clinical diseases such as myocardial hypertrophy and benign prostatic hyperplasia. Therefore, we initiated studies to understand mechanisms underlying regulation of alpha1aAR gene transcription. A genomic clone containing 6.2 kb of 5'-untranslated region of the human alpha1aAR gene was recently isolated. Ribonuclease protection and primer extension assays indicate that alpha1aAR gene transcription occurs at multiple initiation sites with the major site located 696 base pairs upstream of the ATG, where a classic initiator sequence is located. Transfection of luciferase reporter constructs containing varying amounts of 5'-untranslated region into human SK-N-MC neuroblastoma cells indicate that a region extending 125 base pairs upstream from the main transcription initiation site contains full alpha1aAR promoter activity. Furthermore, distinct activator and suppressor elements lie 2-3 and 3-5 kilobase pairs upstream, respectively. Although the alpha1aAR promoter contains neither TATA or CAAT elements, gel shift mobility assays targeting three GC boxes immediately upstream of the main transcription initiation site confirm binding of Sp1. Activity of the alpha1aAR promoter is cell-specific, demonstrating highest activity in cells endogenously expressing alpha1aARs. The human alpha1aAR gene also contains several cis regulatory elements, including several insulin and cAMP response elements. Consistent with these observations, we provide the first evidence that treatment of SK-N-MC cells with insulin and cAMP elevating agents leads to an increase in alpha1aAR expression. In conclusion, these data represent the first characterization of the alpha1aAR gene; our findings should facilitate further studies designed to understand mechanisms regulating alpha1AR subtype-specific expression in healthy and diseased human tissue.


Assuntos
Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Receptores Adrenérgicos alfa 1/genética , Clonagem Molecular , AMP Cíclico/metabolismo , Genes Reguladores , Humanos , Insulina/metabolismo , Luciferases/genética , Luciferases/metabolismo , Dados de Sequência Molecular , Receptores Adrenérgicos alfa 1/metabolismo , Mapeamento por Restrição , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
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