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1.
Breast Cancer Res Treat ; 136(1): 143-51, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22956006

RESUMO

Uncertainty remains about the optimal anti-emetic regimen for control of delayed nausea and vomiting after adjuvant chemotherapy for breast cancer. Many patients receive dexamethasone but complain of insomnia, anxiety/agitation, and indigestion. The aim was to determine if patients receiving chemotherapy for breast cancer prefer treatment with dexamethasone or placebo for prophylaxis against delayed nausea and vomiting, and to compare quality of life (QOL) between the two treatments. In this randomized, double-blind, cross-over trial, we compared oral dexamethasone (4 mg twice daily for 2 days) versus placebo for chemotherapy-naïve patients with breast cancer. All patients received intravenous granisetron and dexamethasone pre-chemotherapy and oral granisetron on day 2. Primary endpoints were: (i) patient preference; (ii) difference between cycles in change of QOL from days 1 to 8. Median age of the 94 women was 51 years (range 27-76): 79 received fluorouracil/epirubicin/cyclophosphamide and 15 received doxorubicin/cyclophosphamide. Thirteen withdrew pre-cycle 2 with no differences between arms. Of 80 patients stating a preference, 31 preferred placebo (39 %, 95 % CI: 28-50 %) and 37 (46 %, 95 % CI: 35-58 %) preferred dexamethasone; 12 had no preference. There were no differences in intensity of vomiting, nausea, or time to onset of vomiting. There was greater decrease in global QOL (p = 0.06) when patients received dexamethasone. No other symptom/QOL domains differed significantly. In conclusion, no significant difference was found in patient preference, QOL, or symptoms regardless of whether dexamethasone or placebo was used after adjuvant chemotherapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Dexametasona , Qualidade de Vida , Adulto , Idoso , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/induzido quimicamente , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Granisetron/administração & dosagem , Granisetron/efeitos adversos , Humanos , Pessoa de Meia-Idade
2.
Breast Cancer Res Treat ; 119(1): 13-24, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19789974

RESUMO

The purpose of the study is to review the clinical studies relevant to the prognosis and prognostic associations of BRCA1- and BRCA2-associated breast cancers. Reports of relevant studies obtained from a MEDLINE search and references from these articles were critically reviewed. A number of methodologic limitations have been identified in the early studies. More recent studies have failed to demonstrate, for the most part, a significant overall survival difference between BRCA-associated breast cancers and sporadic breast cancers. The risk of in-breast tumor recurrence also appears to be similar in the first 5 years following a breast cancer diagnosis with apparent increase in the risk after 5 years in one study. Many in-breast tumor recurrences are now considered to be second primary breast cancers. There is a significant increase in the risk of contralateral breast cancers in BRCA mutation carriers with an estimated 10-year risk ranging from 20-40%. The prognosis of BRCA-associated breast cancers appears to be similar to that of sporadic breast cancers based on the current literature. Future data from large prospective cohort studies will be of interest.


Assuntos
Proteína BRCA1/biossíntese , Proteína BRCA2/biossíntese , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Adulto , Proteínas Reguladoras de Apoptose , Estudos de Casos e Controles , Feminino , Genes BRCA1 , Genes BRCA2 , Humanos , Pessoa de Meia-Idade , Prognóstico , Recidiva , Risco , Fatores de Tempo , Resultado do Tratamento
3.
Clin Genet ; 77(3): 273-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20002453

RESUMO

Women who carry BRCA mutations are advised to begin breast cancer screening based on the age-specific risks of breast cancer development. It is not clear to what extent the family history of breast cancer influences age of onset. We evaluated the use of family history to predict the age of breast cancer onset in BRCA mutation carriers. Pedigrees from an Ontario-based registry were reviewed to identify the index case of breast cancer (most recent diagnosis) and other family cases of breast cancer. The youngest age of breast cancer diagnosis and mean age at breast cancer diagnosis in the other family cases were compared to the age of onset in the index case. The 260 BRCA1 and 213 BRCA2 pedigrees were reviewed. In BRCA2 families, the index case was diagnosed on average at 44.4 years when the youngest reported family case was less than or equal to 35 years, compared to 51.9 years when the earliest cases were diagnosed after age 50 (p = 0.04). A modest trend was seen for BRCA1 carriers, but this was not statistically significant. To a small extent, the onset of breast cancer in a BRCA2 mutation carrier can be predicted from her family history of cancer, however, the trend is modest and should not alter clinical recommendations regarding initiation of screening.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Adulto , Idade de Início , Idoso , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Linhagem , Penetrância
4.
Leukemia ; 19(7): 1161-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15902297

RESUMO

Acute myeloblastic leukemia (AML) may be classified in a number of ways. Using the French American British classification, the M3 form of the disease or acute promyelocytic leukemia (APL) has been found to be sensitive in vitro and in vivo to the retinoid all trans retinoic acid (ATRA). The mechanism for this is by restoration of normal gene expression through the release of histone deacetylase complexes (HDACs). In contrast to APL, other forms of AML are either nonresponsive or show blunted responses to ATRA. We evaluated if the inhibitor of HDAC activity, valproic acid (VPA), could mimic or enhance retinoid sensitivity in the AML cell line, OCI/AML-2, and clinical samples derived from patients with AML. An Affymetrix GeneChip experiment demonstrated that VPA modulated the expression of numerous genes in OCI/AML-2 cells that were not affected by ATRA including p21, a retinoid responsive gene in APL. VPA induced p21 expression in OCI/AML-2 cells and the majority of the AML samples tested; this was associated with cell cycle arrest and apoptosis not seen with ATRA alone. The addition of ATRA to VPA accentuated many of these responses, supporting the potential beneficial combination of these drugs in the treatment of AML.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores de Histona Desacetilases , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/enzimologia , Tretinoína/farmacologia , Ácido Valproico/farmacologia , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21 , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Regulação da Expressão Gênica , Histona Desacetilases/genética , Humanos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Relação Estrutura-Atividade
5.
J Natl Cancer Inst ; 92(16): 1321-9, 2000 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-10944554

RESUMO

BACKGROUND: Best supportive care has long been considered to be the standard therapy for metastatic non-small-cell lung cancer (NSCLC). There is now evidence from randomized trials that a number of chemotherapy regimens can palliate cancer-related symptoms and modestly improve survival. We show how cost-effectiveness analyses can be used to make choices between different (ambulatory) chemotherapy regimens. METHODS: Clinical algorithms describing the diagnosis, staging, and treatment of metastatic NSCLC were incorporated into Statistics Canada's Population Health Model. Using consistent methodology, we assessed the cost-effectiveness of several chemotherapeutic interventions: a combination of vindesine (VDS) plus cisplatin, etoposide (VP-16) plus cisplatin, vinblastine (VLB) plus cisplatin, vinorelbine (Navelbine; NVB) plus cisplatin, paclitaxel (Taxol) plus cisplatin, and gemcitabine (GEM) and NVB alone. We calculated the total chemotherapy costs in 1995 Canadian dollars, the cost per case, the average life-years saved, and the cost per life-year saved. Using the Population Health Model, we then constructed an advanced decision framework that rank-ordered the various treatment regimens so as to optimize benefit below various cost-effectiveness thresholds. RESULTS: One regimen (VLB plus cisplatin) appears to result in better survival and lower health care expenditures than best supportive care. By use of cost-effectiveness thresholds of $25,000 and $50,000 per life-year gained, NVB plus cisplatin is the preferred regimen. When quality of life is considered, however, GEM is preferred to NVB plus cisplatin at a threshold value of $50,000. At thresholds of $75 000 and $100,000, paclitaxel plus cisplatin at a dose of 135 mg/m(2) is the preferred regimen. At thresholds of $50,000 and above, best supportive care is the least preferred regimen. CONCLUSIONS: This decision framework allows the comparison of different treatment regimens based on various cost-effectiveness thresholds. Our analysis also supports the use of chemotherapy regimens and the abandonment of best supportive care as the standard of care for patients with advanced NSCLC. [J Natl Cancer Inst 2000;92:1321-9].


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Cuidados Paliativos/métodos , Algoritmos , Assistência Ambulatorial , Carcinoma Pulmonar de Células não Pequenas/economia , Carcinoma Pulmonar de Células não Pequenas/secundário , Análise Custo-Benefício , Árvores de Decisões , Humanos , Neoplasias Pulmonares/economia , Neoplasias Pulmonares/patologia , Cuidados Paliativos/economia , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Análise de Sobrevida , Resultado do Tratamento , Estados Unidos , Valor da Vida
6.
Semin Oncol ; 27(6 Suppl 12): 42-52, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11226000

RESUMO

Follicular lymphoma is a low-grade, indolent non-Hodgkin's lymphoma characterized by the presence of the t(14;18) translocation. The detection of this translocation using polymerase chain reaction techniques has been increasingly studied. However, the diagnostic and prognostic value of detecting t(14;18) rearrangements has been questioned. Translocation has been identified in a significant proportion of healthy donors and patients with nonmalignant diseases. Clearance of t(14;18) rearrangements following conventional treatments, purging of bone marrow/peripheral blood stem cells, and transplantation is associated with improved long-term outcome of patients with follicular lymphoma. Until randomized studies confirm the clinical utility of polymerase chain reaction detection of the translocation, emphasis should be placed on improving the accuracy and reproducibility of polymerase chain reaction techniques, and standardizing assays among laboratories.


Assuntos
Linfoma Folicular/diagnóstico , Antígenos CD34/sangue , Transplante de Medula Óssea/métodos , Terapia Combinada , Diagnóstico Diferencial , Genes bcl-2/genética , Humanos , Imunoterapia , Linfoma Folicular/genética , Linfoma Folicular/terapia , Conformação Molecular , Reação em Cadeia da Polimerase , Translocação Genética
7.
Am J Med Genet ; 88(5): 567-87, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10490718

RESUMO

We completed a genome-wide scan for susceptibility loci for bipolar affective disorders in families derived from a rather homogeneous population in the Province of Québec. The genetic homogeneity of this population stems from the migration of founding families into this relatively isolated area of Québec in the 1830s. A possible founder effect, combined with a prevalence of very large families, makes this population ideal for linkage studies. Genealogies for probands can be readily constructed from a population database of acts of baptism and marriage from the early 1830s up to the present time (the BALSAC register). We chose probands with a DSM III diagnosis of bipolar affective disorder and who may be grouped within large families having genealogical origins with the founding population of the Saguenay-Lac-St-Jean area. Living members (n approximately 120) of a very large pedigree were interviewed using the Structured Clinical Interview for DSM III (SCID I), SCID II, and with a family history questionnaire. A diagnostic panel evaluated multisource information (interview, medical records, family history) and pronounced best-estimate consensus diagnoses on all family members. Linkage, SimAPM, SimIBD, and sib-pair analyses have been performed with 332 microsatellite probes covering the entire genome at an average spacing of 11 cM. GENEHUNTER and haplotype analyses were performed on regions of interest. Analysis of a second large pedigree in the same regions of interest permitted confirmation of presumed linkages found in the region of chromosome 12q23-q24.


Assuntos
Transtorno Bipolar/genética , Cromossomos Humanos Par 12 , Ligação Genética , Cromossomos Humanos Par 5 , Feminino , Seguimentos , Heterogeneidade Genética , Marcadores Genéticos , Predisposição Genética para Doença , Testes Genéticos , Genótipo , Haplótipos , Humanos , Escore Lod , Masculino , Linhagem , Quebeque
8.
Bone Marrow Transplant ; 28(4): 387-91, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11571512

RESUMO

Survivors of autologous blood or marrow transplantation (ABMT) are predisposed to decreased bone mineral density (BMD), but data are lacking on the incidence and risk factors for this condition. Therefore, we measured BMD in 64 of 68 consecutive ABMT survivors (35 men and 29 women) attending the University of Toronto ABMT long-term follow-up clinic. Patients were evaluated a median of 4.2 years (range: 4.9 months-11.4 years) after ABMT. Median age at evaluation was 49.6 years (range: 23.5-68.2 years). At the L1-L4 vertebrae, 17 (26%) patients (eight men and nine women) had osteopenia and one male (2%) had osteoporosis. Mean BMD at L1-L4 did not differ from healthy young adults or age and sex matched controls. At the femoral neck, 30 patients (46%) (18 men and 12 women) had osteopenia and five (8%) (two men and three women) had osteoporosis. Mean BMD at the femoral neck was significantly lower than in healthy young adults and age- and sex-matched controls. By regression analysis, patients with decreased BMD were older than those with normal BMD (P = 0.02). Gender, body mass index, time from BMT to evaluation and presence of hypogonadism were not associated with decreased BMD. Treatment of decreased bone density was instituted and follow-up data were obtained 1 year after treatment in 22 of 39 patients with reduced BMD. Nineteen (86%) patients had stabilization or improvement of their bone density at follow-up. We conclude that, after ABMT, over half of the patients have evidence of osteopenia or osteoporosis. Men and women were equally affected. In our study, only older age at evaluation was predictive for loss of BMD. We recommend the measurement of BMD as an integral component to the follow-up of ABMT patients.


Assuntos
Densidade Óssea , Transplante de Medula Óssea , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Adulto , Fatores Etários , Idoso , Doenças Ósseas Metabólicas/etiologia , Doenças Ósseas Metabólicas/fisiopatologia , Feminino , Colo do Fêmur/fisiopatologia , Seguimentos , Humanos , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Fatores Sexuais , Sobreviventes , Transplante Autólogo
9.
Life Sci ; 40(2): 183-91, 1987 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-3796219

RESUMO

Dopamine-beta-hydroxylase catalyzes the beta-oxidation of dopamine to noradrenaline while phenylethanolamine-N-methyltransferase converts noradrenaline to adrenaline. Since catecholamine sulfates represent the predominant form of catecholamines in human tissues, we have studied the role of dopamine sulfate and noradrenaline sulfate as alternate substrates for dopamine-beta-hydroxylase and phenylethanolamine-N-methyltransferase, respectively. Dopamine 3-sulfate, dopamine 4-sulfate and noradrenaline 3-sulfate were chemically synthesized and exhaustively purified by ion-exchange chromatography. Dopamine-beta-hydroxylase and phenylethanolamine-N-methyltransferase were partially purified from human adrenals. Using tyramine as substrate, dopamine-beta-hydroxylase is slightly inhibited by dopamine 3-sulfate according to some irreversible or mixed mechanisms. When dopamine-beta-hydroxylase was incubated with dopamine 3-sulfate or dopamine 4-sulfate, we were not able to find any synthesis of either noradrenaline sulfate or free noradrenaline. Using phenylethanolamine as substrate, the enzymatic activity of phenylethanolamine-N-methyltransferase remains unchanged with addition of dopamine 3-sulfate, dopamine 4-sulfate or noradrenaline 3-sulfate. It was concluded that dopamine sulfate is not an alternate substrate for either dopamine-beta-hydroxylase or phenylethanolamine-N-methyltransferase nor is noradrenaline 3-sulfate an alternate substrate for phenylethanolamine-N-methyltransferase.


Assuntos
Dopamina/análogos & derivados , Adulto , Animais , Bovinos , Dopamina/metabolismo , Dopamina beta-Hidroxilase/antagonistas & inibidores , Dopamina beta-Hidroxilase/metabolismo , Etanolaminas/metabolismo , Humanos , Masculino , Feniletanolamina N-Metiltransferase/antagonistas & inibidores , Feniletanolamina N-Metiltransferase/metabolismo , Ratos , Tiramina/metabolismo
10.
J Emerg Med ; 16(4): 593-6, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9696176

RESUMO

Cardiovascular abnormalities are frequently encountered in patients with Turner's syndrome. These include coarctation of the aorta, aortic root dilatation, bicuspid aortic valve, atrial and ventricular septal defects. Aortic dissection is a rare but devastating complication of Turner's syndrome that usually occurs in adulthood. We report a case of Turner's syndrome with coarctation of the aorta and chronic aortic dissection, and review the relevant literature. There have been 21 prior reported cases of aortic dissection in patients with Turner's syndrome. Possible etiologic factors contributing to the occurrence of aortic dissection in this syndrome are protean. They include the presence of cystic medial necrosis, coarctation of the aorta, bicuspid aortic valve, aortic root dilatation, and hypertension, although cases of aortic dissection and Turner's syndrome have been described in patients without any risk factors. As our knowledge of the natural history of congenital heart defects and risk factors for aortic dissection in Turner's syndrome is limited, periodic cardiac evaluation of these patients may be warranted. Early recognition and treatment of this potentially lethal complication of Turner's syndrome is essential.


Assuntos
Aneurisma da Aorta Torácica/complicações , Dissecção Aórtica/complicações , Síndrome de Turner/complicações , Adulto , Coartação Aórtica/complicações , Feminino , Humanos
11.
Br J Educ Psychol ; 68 ( Pt 3): 309-19, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9788208

RESUMO

BACKGROUND: Current goal theory models assume that learning goals are adaptive in academic contexts and that performance goals lead to less positive patterns of motivation and self-regulation. These models also implicitly assume that the adaptive nature of these goals is the same at all academic levels. AIMS: The objectives of this study were to examine how combined learning and performance goals are related to self-regulation and academic performance, and whether there is a developmental trend in these relations. SAMPLE: A total of 1072 junior (N = 408, mean age = 11.9), middle (N = 323, mean age = 13.7), and senior (N = 341, mean age = 15.7) high school students were examined. METHOD: They were administered a questionnaire assessing their learning and performance goals and reported their self-regulatory strategies while studying. RESULTS: Analyses showed that whatever their performance goals, having high learning goals promoted younger students' self-regulation. They also showed that, contrary to the findings for younger students, performance goals were related to self-regulation and academic performance at higher school levels. Furthermore, high performance goals were found to alleviate the negative effects of low learning goals for older students. CONCLUSIONS: These findings suggest that the adaptive nature of goals could change across development. This could be due to contextual factors such as the increasing importance of obtaining good grades to access higher academic levels. Future research should address this issue.


Assuntos
Objetivos , Aprendizagem/fisiologia , Estudantes/psicologia , Adolescente , Criança , Feminino , Humanos , Masculino , Inquéritos e Questionários
13.
Ann Oncol ; 17(6): 952-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16565212

RESUMO

BACKGROUND: Temozolomide is an oral alkylating agent that crosses the blood-brain barrier, and has preclinical activity in breast cancer. This phase II trial sought to determine the activity and toxicity of temozolomide in metastatic breast cancer (MBC). Temozolomide was administered in a dose dense schedule of 150 mg/m(2) on days 1-7 and 15-21 in a 28-day cycle. MATERIALS AND METHODS: Patients had unidimensional disease for response assessment by RECIST criteria, up to two prior chemotherapy regimens for MBC, and may have had brain metastases if radiation was not expected to be required within 4 weeks. RESULTS: Nineteen women were entered on the study. All were evaluable for toxicity and 18 were evaluable for response. The median age was 54 years; 14 had prior chemotherapy for MBC and 12 had prior hormones. Sites of disease included bone, brain, liver and lung. Treatment was well tolerated with 14/19 receiving >90% planned dose intensity. Common grade 1-3 drug-related effects included nausea, fatigue, vomiting, anorexia and skin rash. Grade 3-4 hematologic toxicities included granulocytopenia and thrombocytopenia. Of the 18 evaluable patients, there were no objective responses; three had stable disease and 15 progressive disease. CONCLUSIONS: No responses to temozolomide were documented in these heavily pretreated women with extensive MBC including brain metastases.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Dacarbazina/análogos & derivados , Administração Oral , Adulto , Idoso , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/toxicidade , Dacarbazina/administração & dosagem , Dacarbazina/uso terapêutico , Dacarbazina/toxicidade , Progressão da Doença , Esquema de Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Seleção de Pacientes , Temozolomida , Resultado do Tratamento
14.
Br J Haematol ; 91(3): 668-70, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8555073

RESUMO

Giant lymph node hyperplasia (GLNH) or Castleman disease is a heterogenous group of atypical lymphoproliferative disorders. Two main histologic variants, the hyaline vascular variant and the plasma cell variant, have been recognized. Although localized GLNH can often be managed successfully with surgery, optimal therapy for multifocal disease has yet to be identified. We report two cases of GLNH treated with 2-chloro-deoxyadenosine (2-CDA), a synthetic purine analogue. 2-CDA was utilized based on its relative lymphocytic toxicity and the putative pathophysiologic process in GLNH being either hamartomatous overgrowth (hyaline-vascular variant) or immune dysfunction and lymphoproliferation (plasma cell variant). One patient with unresectable localized hyaline-vascular GLNH has had a 9-month continuous complete remission following two courses of 2-CDA therapy followed by radiation therapy. The second patient with disseminated plasma cell type had a partial response to two cycles of 2-CDA therapy; however, further cycles were not given due to development of possible early neurotoxicity. Although the optimal management of non-resectable GLNH is yet to be determined, 2-CDA appears to be a viable therapeutic option for patients with this disease process.


Assuntos
Antineoplásicos/uso terapêutico , Hiperplasia do Linfonodo Gigante/tratamento farmacológico , Cladribina/uso terapêutico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Semin Respir Crit Care Med ; 21(5): 375-84, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-16088749

RESUMO

The purpose of this study is to review the economics of lung cancer management. The economic literature that relates to the diagnosis, treatment, and palliation of lung cancer as well as the pertinent methodological literature were reviewed. Lung cancer treatment is moderately expensive. The overall cost to society is significant given its high incidence. The cost of staging lung cancer can be minimized through the judicious use of diagnostic and staging procedures. The cost-effectiveness of combined modality therapy and palliative chemotherapy for lung cancer appears reasonable when compared with commonly accepted medical interventions. Based on this review, current approaches to lung cancer diagnosis and treatment are, for the most part, cost-effective. Reasons for inconsistent practice patterns in the management of lung cancer in the medical community should be further explored.

16.
Theor Appl Genet ; 80(6): 795-800, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24221111

RESUMO

Mutagenesis provoked by exposure at elevated temperature of the cold-adapted, arctic Rhizobium strain N31 resulted in the generation of five deletion mutants, which exhibited loss of their smaller plasmid (200 kb), whereas the larger plasmid (> 500 kb) was still present in all mutants. Deletion mutants did not show differences from the wild type in the antibiotic resistance pattern, the carbohydrates and organic acids utilization, and the growth rate at low temperature. However, deletion mutants differed from the wild type and among themselves in the ex planta nitrogenase activity, the nodulation index, and the symbiotic effectiveness. The deletion mutant N31.6rif (r) showed higher nodulation index and exhibited higher nitrogenase activity and symbiotic efficiency than the other deletion mutants and the wild type. The process of deletion mutation resulted in the improvement of an arctic Rhizobium strain having an earlier and higher symbiotic nitrogen fixation efficiency than the wild type.

17.
Bull Environ Contam Toxicol ; 5(1): 34-7, 1970 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24185721

RESUMO

Formation of asymmetric azobenzenes from variously substituted aniline pairs in soil and by peroxidase pointed to the existence of labile intermediates. These were tentatively identified as the respective phenylhydroxylamines.

18.
Appl Microbiol ; 18(2): 274-5, 1969 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4185238

RESUMO

Peroxidase-positive microorganisms were enumerated on agar plates by use of a p-anisidine-H(2)O(2) spray. Combined with replica-plating, the same technique allowed the selective isolation of peroxidase-producing microbial cultures.


Assuntos
Técnicas Bacteriológicas , Fungos/isolamento & purificação , Peroxidases , Actinomycetales/isolamento & purificação , Bactérias/enzimologia , Bactérias/isolamento & purificação , Meios de Cultura , Fungos/enzimologia , Métodos , Seleção Genética , Coloração e Rotulagem
19.
Appl Microbiol ; 18(3): 369-75, 1969 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-5373674

RESUMO

Organisms capable of decomposing N-(3,4-dichlorophenyl)-2-methylpentanamide (Karsil) were isolated, identified, and tested for their ability to hydrolyze this herbicide. Primary products of Karsil decomposition by cells and cell-free extracts of a Penicillium sp. were identified as 2-methyl-valeric acid and 3,4-dichloroaniline. The Karsil acylamidase (EC 3.5.1.a aryl acylamine amidohydrolase) was an induced enzyme. It was partially purified and tested for its ability to hydrolyze 25 related compounds. Some relations between the structures of these compounds and their susceptibility to enzymatic hydrolysis were discerned.


Assuntos
Anilidas/metabolismo , Herbicidas/metabolismo , Penicillium/metabolismo , Valeratos/metabolismo , Amidoidrolases/isolamento & purificação , Amidoidrolases/metabolismo , Compostos de Anilina/análise , Compostos de Anilina/biossíntese , Fenômenos Químicos , Química , Cromatografia Gasosa , Indução Enzimática , Penicillium/análise , Penicillium/enzimologia , Fatores de Tempo , Valeratos/análise
20.
J Bacteriol ; 171(7): 3926-32, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2661539

RESUMO

The gltX gene, coding for the glutamyl-tRNA synthetase of Rhizobium meliloti A2, was cloned by using as probe a synthetic oligonucleotide corresponding to the amino acid sequence of a segment of the glutamyl-tRNA synthetase. The codons chosen for this 42-mer were those most frequently used in a set of R. meliloti genes. DNA sequence analysis revealed an open reading frame of 484 codons, encoding a polypeptide of Mr 54,166 containing the amino acid sequences of an NH2-terminal and various internal fragments of the enzyme. Compared with the amino acid sequence of the glutamyl-tRNA synthetase of Escherichia coli, the N-terminal third of the R. meliloti enzyme was strongly conserved (52% identity); the second third was moderately conserved (38% identity) and included a few highly conserved segments, whereas no significant similarity was found in the C-terminal third. These results suggest that the C-terminal part of the protein is probably not involved in the recognition of substrates, a feature shared with other aminoacyl-tRNA synthetases.


Assuntos
Aminoacil-tRNA Sintetases/genética , Proteínas de Bactérias/genética , Genes Bacterianos , Glutamato-tRNA Ligase/genética , Rhizobium/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/isolamento & purificação , Sequência de Bases , Clonagem Molecular/métodos , Códon , Escherichia coli/enzimologia , Escherichia coli/genética , Glutamato-tRNA Ligase/isolamento & purificação , Dados de Sequência Molecular , Rhizobium/genética , Homologia de Sequência do Ácido Nucleico
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