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1.
Ann Oncol ; 27(12): 2224-2229, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27789469

RESUMO

BACKGROUND: Cancer may cause financial difficulties, but its impact in countries with public health systems is unknown. We evaluated the association of financial difficulties with clinical outcomes of cancer patients enrolled in academic clinical trials performed within the Italian public health system. PATIENTS AND METHODS: Data were pooled from 16 prospective multicentre trials in lung, breast or ovarian cancer, using the EORTC quality of life (QOL) C30 questionnaire. Question 28 scores financial difficulties related to disease or treatment in four categories from 'not at all' to 'very much'. We defined financial burden (FB) as any financial difficulty reported at baseline questionnaire, and financial toxicity (FT) as score worsening in a subsequent questionnaire. We investigated (i) the association of FB with clinical outcomes (survival, global QOL response [questions 29/30] and severe toxicity), and (ii) the association of FT with survival. Multivariable analyses were performed using logistic regression models or the Cox model adjusting for trial, gender, age, region and period of enrolment, baseline global QOL and, where appropriate, FB and global QOL response. Results are reported as odds ratio (OR) or hazard ratio (HR) with 95% confidence intervals (CI). RESULTS: At baseline 26% of the 3670 study patients reported FB, significantly correlated with worse baseline global QOL. FB was not associated with risks of death (HR 0.94, 95% CI 0.85-1.04, P = 0.23) and severe toxicity (OR 0.90, 95% CI 0.76-1.06, P = 0.19) but was predictive of a higher chance of worse global QOL response (OR 1.35, 95% CI 1.08-1.70, P = 0.009). During treatment, 2735 (74.5%) patients filled in subsequent questionnaires and 616 (22.5%) developed FT that was significantly associated with an increased risk of death (HR 1.20, 95% CI 1.05-1.37, P = 0.007). Several sensitivity analyses confirmed these findings. CONCLUSION: Even in a public health system, financial difficulties are associated with relevant cancer patients outcomes like QOL and survival. CLINICAL TRIALS NUMBER: Any registered clinical trial number should be indicated after the abstract.


Assuntos
Neoplasias da Mama/economia , Ensaios Clínicos como Assunto/economia , Neoplasias Pulmonares/economia , Neoplasias Ovarianas/economia , Idoso , Neoplasias da Mama/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Modelos Logísticos , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Modelos de Riscos Proporcionais , Qualidade de Vida , Inquéritos e Questionários
2.
Ann Oncol ; 26(4): 675-682, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25488686

RESUMO

BACKGROUND: Evidence on adjuvant chemotherapy in older women with breast cancer is poor. We tested whether weekly docetaxel is more effective than standard chemotherapy. PATIENTS AND METHODS: We carried out a multicenter, randomized phase III study. Women aged 65-79, operated for breast cancer, with average to high risk of recurrence, were allocated 1 : 1 to CMF (cyclophosphamide 600 mg/m², methotrexate 40 mg/m², fluorouracil 600 mg/m², days 1, 8) or docetaxel (35 mg/m(2) days 1, 8, 15) every 4 weeks, for four or six cycles according to hormone receptor status. Primary end point was disease-free survival (DFS). A geriatric assessment was carried out. Quality of life (QoL) was assessed with EORTC C-30 and BR-23 questionnaires. RESULTS: From July 2003 to April 2011, 302 patients were randomized and 299 (152 allocated CMF and 147 docetaxel) were eligible. After 70-month median follow-up, 109 DFS events were observed. Unadjusted hazard ratio (HR) of DFS for docetaxel versus CMF was 1.21 [95% confidence interval (CI) 0.83-1.76, P = 0.32]; DFS estimate at 5 years was 0.69 with CMF and 0.65 with docetaxel. HR of death was 1.34 (95% CI 0.80-2.22, P = 0.26). There was no interaction between treatment arms and geriatric scales measuring patients' ability or comorbidities. Hematological toxicity, mucositis and nausea were worse with CMF; allergy, fatigue, hair loss, onychopathy, dysgeusia, diarrhea, abdominal pain, neuropathy, cardiac and skin toxicity were worse with docetaxel. One death was attributed to CMF and two to docetaxel. Increasing age, impairment in instrumental daily living activities, number of comorbidities and docetaxel treatment were independently associated with severe nonhematological toxicity. QoL was worse with docetaxel for nausea-vomiting, appetite loss, diarrhea, body image, future perspective, treatment side-effects and hair loss items. CONCLUSIONS: Weekly docetaxel is not more effective than standard CMF as adjuvant treatment of older women with breast cancer and worsens QoL and toxicity. CLINICALTRIALSGOV: NCT00331097.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Lobular/tratamento farmacológico , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/mortalidade , Carcinoma Lobular/patologia , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Docetaxel , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Metotrexato/administração & dosagem , Gradação de Tumores , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Taxoides/administração & dosagem
3.
Haemophilia ; 21(1): 140-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25438872

RESUMO

Factor V (FV) deficiency is a rare autosomal recessive bleeding disorder caused by mutations in the F5 gene. FV-deficient patients in whom no mutation or only one mutation is found may harbour large gene rearrangements, which are not detected by conventional mutation screening strategies. The aim of this study was to develop and validate a multiplex ligation-dependent probe amplification (MLPA) assay for the detection of large deletions and duplications in the F5 gene. Twenty-two MLPA probes targeting 19 of the 25 exons and the upstream and downstream regions of the F5 gene were designed and tested in 10 normal controls, a patient with a known heterozygous deletion of F5 exons 1-7 (positive control) and 14 genetically unexplained FV-deficient patients. MLPA results were confirmed by digital PCR on a QuantStudio(™) 3D Digital PCR System. The F5-specific probes yielded a reproducible peak profile in normal controls, correctly detected the known deletion in the positive control and suggested the presence of a novel deletion of exons 9-10 in a patient with undetectable FV levels and only one identified mutation. Follow-up by chip-based digital PCR, long-range PCR and direct sequencing confirmed that this patient carried a heterozygous F5 deletion of 1823 bp extending from intron 8 to intron 10. Bioinformatics sequence analysis pinpointed repetitive elements that might have originated the deletion. In conclusion, we have developed and validated an MLPA assay for the detection of gross F5 gene rearrangements. This assay may represent a valuable tool for the molecular diagnosis of FV deficiency.


Assuntos
Análise Mutacional de DNA/métodos , Deficiência do Fator V/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Feminino , Humanos , Masculino , Mutação
4.
Haemophilia ; 21(2): 241-248, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25470420

RESUMO

Coagulation factor V (FV) deficiency is a rare autosomal recessive bleeding disorder. We investigated a patient with severe FV deficiency (FV:C < 3%) and moderate bleeding symptoms. Thrombin generation experiments showed residual FV expression in the patient's plasma, which was quantified as 0.7 ± 0.3% by a sensitive prothrombinase-based assay. F5 gene sequencing identified a novel missense mutation in exon 4 (c.578G>C, p.Cys193Ser), predicting the abolition of a conserved disulphide bridge, and an apparently synonymous variant in exon 8 (c.1281C>G). The observation that half of the patient's F5 mRNA lacked the last 18 nucleotides of exon 8 prompted us to re-evaluate the c.1281C>G variant for its possible effects on splicing. Bioinformatics sequence analysis predicted that this transversion would activate a cryptic donor splice site and abolish an exonic splicing enhancer. Characterization in a F5 minigene model confirmed that the c.1281C>G variant was responsible for the patient's splicing defect, which could be partially corrected by a mutation-specific morpholino antisense oligonucleotide. The aberrantly spliced F5 mRNA, whose stability was similar to that of the normal mRNA, encoded a putative FV mutant lacking amino acids 427-432. Expression in COS-1 cells indicated that the mutant protein is poorly secreted and not functional. In conclusion, the c.1281C>G mutation, which was predicted to be translationally silent and hence neutral, causes FV deficiency by impairing pre-mRNA splicing. This finding underscores the importance of cDNA analysis for the correct assessment of exonic mutations.


Assuntos
Processamento Alternativo , Deficiência do Fator V/genética , Fator V/genética , Mutação , Animais , Linhagem Celular , Éxons , Deficiência do Fator V/sangue , Deficiência do Fator V/diagnóstico , Expressão Gênica , Humanos , Masculino , Trombina/biossíntese , Adulto Jovem
5.
ESMO Open ; 9(3): 102941, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38452437

RESUMO

BACKGROUND: Oncologists tend to under-report subjective symptoms during cancer treatment. This study describes the under-reporting rate of selected symptoms and explores its association with overall survival (OS). A secondary aim is to test the association of patient-reported symptoms with OS. PATIENTS AND METHODS: This is a post hoc analysis on data pooled from 12 randomized trials, promoted by the National Cancer Institute of Naples (Italy), enrolling patients between 2002 and 2019, with published primary analyses. Occurrence and grade of six side-effects (anorexia, nausea, vomiting, constipation, diarrhea and fatigue) reported by physicians were compared with corresponding symptoms reported by patients in quality-of-life (QoL) questionnaires. Under-reporting was defined as the rate of cases reported grade 0 by the physician while grade ≥1 by the patient. Prognostic value was tested in a multivariable model stratified by trial, including age, sex and performance status as confounders. A landmark threshold was defined for OS analyses. RESULTS: 3792 patients with advanced lung, ovarian, pancreatic, breast or colorectal cancer were pooled; 2603 (68.6%) were eligible having at least one toxicity assessment and one QoL questionnaire, before the first planned disease restaging. Concordance between physicians' and patients' reporting was low with Cohen's k coefficients ranging from 0.03 (fatigue) to 0.33 (vomiting). Under-reporting ranged from 52.7% (nausea) to 80.5% (anorexia), and was not associated with OS. Patient-reported anorexia, vomiting and fatigue ('a little' or more) were significantly associated with shorter OS. CONCLUSIONS: Under-reporting of treatment side-effects is frequent, but it does not affect OS. Patients' reported symptoms should be used for prognostic evaluation.


Assuntos
Neoplasias , Qualidade de Vida , Humanos , Anorexia/complicações , Fadiga/etiologia , Náusea/etiologia , Neoplasias/terapia , Neoplasias/complicações , Prognóstico , Vômito , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Ann Oncol ; 23(8): 2027-2033, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22412041

RESUMO

BACKGROUND: To measure bone mineral density (BMD) reduction produced by letrozole as compared with tamoxifen and the benefit of the addition of zoledronic acid. PATIENTS AND METHODS: A phase 3 trial comparing tamoxifen, letrozole or letrozole+zoledronic acid in patients with hormone receptor-positive early breast cancer was conducted; triptorelin was given to premenopausal patients. Two comparisons were planned: letrozole versus tamoxifen and letrozole+zoledronic acid versus letrozole. Primary end point was the difference in 1-year change of T-score at lumbar spine (LTS) measured by dual energy X-ray absorptiometry scan. RESULTS: Out of 483 patients enrolled, 459 were available for primary analyses. Median age was 50 (range 28-80). The estimated mean difference (95% confidence interval [CI]) in 1-year change of LTS was equal to -0.30 (95% CI -0.44 to -0.17) in the letrozole versus tamoxifen comparison (P<0.0001) and to +0.60 (95% CI +0.46 to +0.77) in the letrozole+zoledronic acid versus letrozole comparison (P<0.0001). Bone damage by letrozole decreased with increasing baseline body mass index in premenopausal, but not postmenopausal, patients (interaction test P=0.004 and 0.47, respectively). CONCLUSIONS: In the HOBOE (HOrmonal BOne Effects) trial, the positive effect of zoledronic acid on BMD largely counteracts damage produced by letrozole as compared with tamoxifen. Letrozole effect is lower among overweight/obese premenopausal patients.


Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Difosfonatos/uso terapêutico , Imidazóis/uso terapêutico , Tamoxifeno/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Estradiol/metabolismo , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nitrilas/efeitos adversos , Nitrilas/uso terapêutico , Tamoxifeno/efeitos adversos , Triazóis/efeitos adversos , Triazóis/uso terapêutico , Ácido Zoledrônico
7.
Cancer Res ; 51(15): 3965-71, 1991 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-1855213

RESUMO

In this paper we demonstrate that the mutants CHO7PV and CHO4PV isolated by us from the CHO-K1 prol- cell line represent two new complementation groups of UV-sensitive excision repair-defective rodent mutants. We have classified the mutant CHO7PV as representative of Group 9 and CHO4PV as representative of Group 10. Cellular and biochemical characterization of these mutants indicates that they are moderately sensitive to a broad spectrum of mutagens (UV and mono- and bifunctional alkylating agents), partially unable to perform UV-induced DNA repair synthesis, and partially defective in the incision step of the DNA excision repair pathway and in the removal of the two main lesions caused by UV [cyclobutane pyrimidine dimers and (6-4) photo-products]. In terms of UV survival and incision, CHO4PV is apparently more defective than CHO7PV (40% and 50% of wild-type survival, respectively, and 55% and 75% of wild-type incision), whereas when repair DNA synthesis and lesion removal are compared, CHO7PV seems to be more severely affected (30% of wild-type unscheduled DNA synthesis in CHO7PV and 60% in CHO4PV). This suggests a subtlety in the relation between removal of these specific lesions and overall repair capacity and survival.


Assuntos
Linhagem Celular/fisiologia , Reparo do DNA/genética , DNA/efeitos da radiação , Animais , Linhagem Celular/efeitos da radiação , Cricetinae , Cricetulus , DNA/genética , Dano ao DNA/genética , Teste de Complementação Genética , Células Híbridas/fisiologia , Mutação/efeitos da radiação , Raios Ultravioleta
8.
Cancer Lett ; 7(4): 235-41, 1979 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-509406

RESUMO

We analysed by liquid scintillation counting and by autoradiography the DNA repair synthesis induced by UV irradiation in mononucleated cells from peripheral blood of 'hairy cell leukaemia' patients. In 9 out of 12 patients the repair activity values obtained in repeated assays were found to be significantly lower than those of healthy donors.


Assuntos
Reparo do DNA/efeitos da radiação , DNA de Neoplasias/sangue , Leucemia de Células Pilosas/sangue , Raios Ultravioleta , Adulto , Feminino , Humanos , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
9.
Exp Gerontol ; 34(5): 715-9, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10530795

RESUMO

We describe the presence of metaphases with non-random gain of one or two chromosomes in a skin fibroblast strain derived from a centenarian individual. The extra elements were chromosomes 7, X, and 18, and, among these, the most frequent was a 7. During in vitro propagation +7 cells seemed to be stable and overrode the diploid ones. After prolonged growth in culture, the cell population displayed the typical senescence signs. Our findings confirm the proneness to aneuploidy in cells from aged individuals and indicate that, while the presence of a trisomic 7 may confer a selective advantage to cells grown in vitro, it does not seem to prevent cellular senescence.


Assuntos
Cromossomos Humanos Par 7 , Pele/citologia , Trissomia , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular , Cromossomos Humanos Par 18 , DNA Satélite/genética , Feminino , Fibroblastos/citologia , Humanos , Mitose , Cromossomo X
10.
Dis Markers ; 8(3): 125-36, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2272148

RESUMO

In cells from a papulonodular formation of a patient with the clinical and cellular phenotype of the variant form of xeroderma pigmentosum (XP-V), clonal rearrangements involving different chromosomes were observed. This finding confirms the literature data suggesting that multiple non-specific chromosome anomalies are typical of pre-malignant and malignant skin lesions.


Assuntos
Aberrações Cromossômicas , Lesões Pré-Cancerosas/genética , Pele/patologia , Xeroderma Pigmentoso/genética , Adulto , Carcinoma Basocelular/etiologia , Carcinoma de Células Escamosas/etiologia , Células Clonais/ultraestrutura , Consanguinidade , Reparo do DNA , Neoplasias Faciais/etiologia , Feminino , Fibroblastos/efeitos da radiação , Fibroblastos/ultraestrutura , Marcadores Genéticos , Humanos , Melanoma/etiologia , Neoplasias Primárias Múltiplas/etiologia , Linhagem , Lesões Pré-Cancerosas/etiologia , Tolerância a Radiação , Pele/efeitos da radiação , Raios Ultravioleta , Xeroderma Pigmentoso/complicações
11.
Cancer Genet Cytogenet ; 79(1): 41-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7850750

RESUMO

Cytogenetic analysis was performed in a fibroblast clone (XP9UV25) selected for anchorage-independent growth from an XP strain of normal origin and characterized by the presence of clonal chromosome rearrangements. A dicentric chromosome involving the 5p and 16q telomeric regions was observed in XP9UV25 cells at the fifth passage from colony isolation and at successive passages. The specific anomaly was present with increasing frequency (from 22 to 60% of mitoses) during culture propagation, undergoing rearrangements that gave rise to: 1) (5;16) dicentrics with deletions or duplications of the intercentromeric region; 2) homodicentrics for chromosomes 5 or 16, either end-to-end associations or rearranged; and 3) derivative 5p+ and 16q+ monocentric chromosomes. The frequency of other anomalies involving other chromosomes was negligible. These findings represent the first demonstration that a telomeric association leads to a variety of balanced and unbalanced chromosome rearrangements. These rearrangements may result from asymmetric interchanges between sister chromatids, "bridge-breakage-fusion" events during cell division, breakage and reunion of isochromatids, and breakage followed by healing of the ends. The type of anomaly and the sequence of karyotypic changes we observed in the XP9UV25 clone and their mechanisms of origin may be the same as those occurring during transformation from diploidy to aneuploidy in neoplastic cells.


Assuntos
Aberrações Cromossômicas , Xeroderma Pigmentoso/genética , Deleção Cromossômica , Células Clonais , Fibroblastos/química , Humanos , Metáfase/genética , Mitose/genética
12.
Cancer Genet Cytogenet ; 51(1): 89-101, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1984853

RESUMO

Chromosome analysis was carried out in cultured fibroblasts from unaffected skin of five unrelated xeroderma pigmentosum (XP) patients and nine family members. Structural chromosome changes were observed in cultures from all examined individuals. Furthermore, in one XPD patient and in one XPC patient and his parents, cytogenetically abnormal clones were detected. Some of these clones were present starting from the primary explant. This cytogenetic pattern is similar to that observed in an XPC patient previously studied by us. The analysis of breakpoint distribution from clonal and non-clonal chromosome rearrangements showed that some breakpoints were more frequent and common to different families or to different family members although definite evidence of preferential involvement of chromosome bands was not obtained. This investigation indicates that there is a consistent tendency toward chromosome instability in XP mutation carriers. The instability could be related to the multiple chromosome anomalies characterizing skin tumors in XP subjects.


Assuntos
Aberrações Cromossômicas , Xeroderma Pigmentoso/genética , Adolescente , Adulto , Pré-Escolar , Mapeamento Cromossômico , Fibroblastos/patologia , Heterozigoto , Homozigoto , Humanos , Cariotipagem , Pessoa de Meia-Idade
13.
Cancer Genet Cytogenet ; 95(2): 130-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9169029

RESUMO

In a human fibroblast clone we studied the evolution, during culture propagation, of a dicentric chromosome consisting of the end-to-end association of the short arm of chromosome 5 and the long arm of chromosome 16. Dual-color fluorescence in situ hybridization (FISH) with painting probes allowed us to define the structure of a variety of derivative chromosomes and to identify the mechanisms by which they originated. Asymmetric interchanges involving the intercentromeric region of the dicentric, bridge-breakage-fusion events, or breaks followed by sister chromatid fusion, originate unstable hetero- or homodicentric chromosomes with deletion or duplication; breakages not followed by reunion, or intradicentric recombination, presumably originate stable rearranged monocentric chromosomes. The variety of the derivatives is extremely large because the observed events may involve any site of the intercentromeric region, although the majority of them occurs after a break in 16qh. The results of this investigation document the evolution through successive steps of a telomeric fusion, a chromosome anomaly frequently observed in tumor and senescent cells. They also demonstrate that in cultured cells of normal origin, starting with this anomaly, various chromosomal mechanisms may produce translocations, duplications, and deletions. The karyotype instability produced by a telomeric fusion can be relevant for carcinogenesis because it may generate genetic changes critical in the multistep process of transformation.


Assuntos
Aberrações Cromossômicas , Fibroblastos/ultraestrutura , Telômero , Células Cultivadas , Humanos , Hibridização in Situ Fluorescente
14.
Arch Dermatol Res ; 280 Suppl: S19-23, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3408258

RESUMO

Genetic instability in nevoid basal cell carcinoma syndrome (NBCCS) was investigated by measuring in lymphocytes obtained from four patients the level of UV-induced DNA repair synthesis, the DNA replication rate after treatment with different mutagens (UV light, mono- and bifunctional alkylating agents), the baseline mutation frequency, and the spontaneous chromosome breakage. All the parameters analyzed showed normal values; only the response to mitogens in NBCCS lymphocytes was delayed in comparison to that in normal donors. Our findings indicate that chromosomal instability and cellular UV hypersensitivity described in some NBCCS patients are not distinctive and constant features of NBCCS.


Assuntos
Síndrome do Nevo Basocelular/complicações , Carcinoma Basocelular/complicações , Cromossomos Humanos/ultraestrutura , DNA de Neoplasias/efeitos da radiação , Mutagênicos/farmacologia , Mutação , Adolescente , Adulto , Aberrações Cromossômicas , Reparo do DNA/efeitos da radiação , Replicação do DNA/efeitos dos fármacos , Replicação do DNA/efeitos da radiação , DNA de Neoplasias/efeitos dos fármacos , Resistência a Medicamentos/genética , Feminino , Humanos , Linfócitos/análise , Masculino , Pessoa de Meia-Idade , Tioguanina/farmacologia , Raios Ultravioleta
15.
Mutat Res ; 139(2): 67-70, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6694664

RESUMO

The effect of MTX on chromosome morphology was analyzed in cultured lymphocytes, and a high percentage of aberrant mitoses was found. Chromosome anomalies, such as gaps and breaks, are observed on all the chromosomes, but are preferentially located on chromosome n.3 at band p14. When the cells were continuously exposed to the drug, the chromosome damage appeared to be particularly severe.


Assuntos
Cromossomos/efeitos dos fármacos , Metotrexato/farmacologia , Células Cultivadas , Aberrações Cromossômicas , Relação Dose-Resposta a Droga , Feminino , Humanos , Linfócitos/ultraestrutura , Mitose/efeitos dos fármacos
16.
Mutat Res ; 142(1-2): 45-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3974598

RESUMO

The correlation between chromosome condensation and amount of repair synthesis after UV irradiation was studied in PHA-stimulated human lymphocytes. The length of selected chromosomes and the number of autoradiographic grains were determined in cells from late prophase to middle metaphase. The statistical analysis of data indicates a highly significant correlation between the two variables and a positive linear regression of the number of grains on chromosome length.


Assuntos
Cromossomos/ultraestrutura , Reparo do DNA , Linfócitos/efeitos da radiação , Mitose , Autorradiografia , DNA/biossíntese , Humanos , Ativação Linfocitária , Linfócitos/fisiologia
17.
Mutat Res ; 191(2): 117-9, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3600693

RESUMO

A normal level of UV-induced DNA-repair synthesis (UDS) was observed in fibroblasts from a patient affected by trichothiodystrophy (TTD) without photosensitivity. This finding indicates that the hypersensitivity to UV light and the reduced UDS due to the presence of xeroderma pigmentosum complementation group D mutation (XP-D), described in photosensitive TTD patients, are not constantly associated with TTD. Complementation analysis in heterokaryons, obtained by fusion of repair-proficient with repair-deficient TTD cells, demonstrates that cells from the patient showing normal photosensitivity are able to restore UDS in UV-hypersensitive TTD cells.


Assuntos
Reparo do DNA , Doenças do Cabelo/genética , Transtornos de Fotossensibilidade/genética , Fusão Celular , Células Cultivadas , Fibroblastos/efeitos da radiação , Fibroblastos/ultraestrutura , Teste de Complementação Genética , Doenças do Cabelo/classificação , Humanos , Deficiência Intelectual/genética , Enxofre/metabolismo , Raios Ultravioleta , Xeroderma Pigmentoso/genética
18.
Mutat Res ; 275(1): 7-11, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1372688

RESUMO

Cytogenetic investigation was carried out on fibroblasts stored in liquid nitrogen during a period of 7-99 months. Cell strains were from 9 individuals, 2 of whom were affected by xeroderma pigmentosum group C (XPC), and 2 XPC heterozygotes. In cell samples from 3 normal subjects and from 1 patient, high frequencies of abnormal mitoses were observed at the first passage after thawing, which returned to normal values after a few subcultures. The most frequent lesions were chromosome gaps and breaks. The cells damaged the most were those from one XP patient. These findings indicate that cells from some individuals are hypersensitive to clastogenic factors acting during freezing and thawing procedures. This sensitivity could be related to the genetic constitution, although the XP homozygous condition is not an essential or sufficient factor.


Assuntos
Aberrações Cromossômicas , Criopreservação , Fibroblastos/ultraestrutura , Adolescente , Adulto , Idoso , Carcinoma Basocelular/ultraestrutura , Células Cultivadas , Criança , Pré-Escolar , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Nitrogênio , Queimadura Solar , Xeroderma Pigmentoso/ultraestrutura
19.
Mutat Res ; 346(2): 61-7, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7885401

RESUMO

In order to study the possible relationship between gene amplification and DNA repair we analyzed the amplification of the CAD gene in four mutants hypersensitive to UV light (CHO43RO, CHO7PV, UV5 and UV61) isolated in vitro from Chinese hamster cell lines (CHO-K1 and AA8). These mutants are characterized by different defects in the nucleotide excision repair mechanism and represent complementation groups 1, 9, 2, and 6 respectively. To evaluate the amplification ability of each cell line we measured the rate of appearance of PALA resistant clones with the Luria and Delbrück fluctuation test. Resistance to PALA is mainly due to amplification of the CAD gene. In the mutants CHO43RO, UV5 and CHO7PV we reproducibly found an amplification rate lower than in the parental cell lines (2-5 times), while in UV61 the amplification rate was about 4 times higher. This result indicates that each mutant is characterized by a specific amplification ability and that the unefficient removal of UV induced DNA damage can be associated with either a higher or a lower amplification rate. However, the analysis of randomly isolated CHO-K1 clones with normal UV sensitivity has shown variability in their amplification ability, making it difficult to relate the specific amplification ability of the mutants to the DNA repair defect and suggesting clonal heterogeneity of the parental population.


Assuntos
Aspartato Carbamoiltransferase/genética , Ácido Aspártico/análogos & derivados , Carbamoil Fosfato Sintase (Glutamina-Hidrolizante)/genética , Reparo do DNA/genética , Di-Hidro-Orotase/genética , Amplificação de Genes , Complexos Multienzimáticos/genética , Ácido Fosfonoacéticos/análogos & derivados , Animais , Ácido Aspártico/farmacologia , Células CHO , Cricetinae , Resistência a Medicamentos/genética , Mutagênese/genética , Ácido Fosfonoacéticos/farmacologia , Tolerância a Radiação/genética , Raios Ultravioleta
20.
Mutat Res ; 70(3): 343-50, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-6155609

RESUMO

The frequency of sister-chromatid exchanges (SCE) was determined on second-division metaphases of lymphocytes stimulated by phytohaemagglutinin (PHA) during 9 days of culture. By using either a continuous or a pulsed bromodeoxyuridine (BUdR) treatment, cells were selected that had divided only twice, or at least twice, after different culture periods. No significant differences were observed in the SCE frequencies among the various samples. The incidence of SCE appears to be independent of the proliferation properties of cultured lymphocytes, such as length of cell cycle, fast or delayed response to PHA and number of divisions performed in vitro.


Assuntos
Divisão Celular , Troca Genética , Linfócitos/ultraestrutura , Troca de Cromátide Irmã , Adulto , Bromodesoxiuridina , Células Cultivadas , Feminino , Humanos , Cinética , Coloração e Rotulagem , Fatores de Tempo
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