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1.
Support Care Cancer ; 32(1): 1, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38047975

RESUMO

PURPOSE: To investigate the association of environmental factors, rehabilitation services during therapy and socioeconomic status (SES - insurance type), with neurocognitive outcomes at the end of therapy for survivors of childhood acute lymphoblastic leukemia (ALL). METHODS: Survivors (n = 236) treated on the St. Jude Total Therapy Study 16 completed end of therapy testing with performance measures (IQ, attention, processing speed, fine motor skills, academics) and caregiver ratings (attention, executive function, adaptive skills). Environmental factors were abstracted from the medical record. RESULTS: Distribution of sex (47.3% female, p = 0.399), treatment arm (45.5% low risk, 54.5% standard/high risk p = 0.929), insurance type (47.7% private, 52.3% public/none, p = 0.117), and mean age at diagnosis (7.7 vs. 6.8 years, p = 0.143) were similar for groups with (n = 110; 46.6%) and without (n = 126; 53.6%) rehabilitation services during therapy. Compared to those without rehabilitation, the rehabilitation group (n = 110; 46.4%) had more caregiver reported problems with attention (Z = -0.28 vs. 0.43, p = 0.022), executive function (Z = -0.50 vs. -0.08, p = 0.003), and adaptive skills (Z = -0.41 vs.-0.13, p = 0.031). Among the rehabilitation group, there was no difference in outcomes by insurance status. Among those without rehabilitation, those with public insurance had worse neurocognitive outcomes than those with private insurance in IQ (Z = -0.04 vs. -0.45, p = 0.0115), processing speed (Z = -0.10 vs. -0.75, p = 0.0030), reading (Z = 0.18 vs. -0.59, p < 0.0001), and math (Z = -0.04 vs. -0.50, p = 0.0021). CONCLUSION: Participation in rehabilitation services during early intensive therapy is associated with end of therapy caregiver-reported neurocognitive outcomes in daily life.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Feminino , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Sobreviventes , Função Executiva , Cobertura do Seguro , Prontuários Médicos
2.
Hum Brain Mapp ; 37(12): 4500-4510, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27466157

RESUMO

Parkinson disease (PD) can be considered as a brain multisystemic disease arising from dysfunction in several neural networks. The principal aim of this study was to assess whether large-scale structural topological network changes are detectable in PD patients who have not been exposed yet to dopaminergic therapy (de novo patients). Twenty-one drug-naïve PD patients and thirty healthy controls underwent a 3T structural MRI. Next, Diffusion Tensor Imaging (DTI) and graph theoretic analyses to compute individual structural white-matter (WM) networks were combined. Centrality (degree, eigenvector centrality), segregation (clustering coefficient), and integration measures (efficiency, path length) were assessed in subject-specific structural networks. Moreover, Network-based statistic (NBS) was used to identify whether and which subnetworks were significantly different between PD and control participants. De novo PD patients showed decreased clustering coefficient and strength in specific brain regions such as putamen, pallidum, amygdala, and olfactory cortex compared with healthy controls. Moreover, NBS analyses demonstrated that two specific subnetworks of reduced connectivity characterized the WM structural organization of PD patients. In particular, several key pathways in the limbic system, basal ganglia, and sensorimotor circuits showed reduced patterns of communications when comparing PD patients to controls. This study shows that PD is characterized by a disruption in the structural connectivity of several motor and non-motor regions. These findings provide support to the presence of disconnectivity mechanisms in motor (basal ganglia) as well as in non-motor (e.g., limbic, olfactory) circuits at an early disease stage of PD. Hum Brain Mapp 37:4500-4510, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Doença de Parkinson/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
3.
Pediatr Med Chir ; 36(4): 91, 2014 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-25573707

RESUMO

We describe a case of a 14-years old caucasian female affected by autoimmune hemolytic anemia and thrombocytopenia successfully treated with intravenous immunoglobulin and steroids. Nevertheless, neutropenia occurred during follow-up period. Positivity of direct antiglobulin test and sieric anti-neutrophil antibodies suggested the diagnosis of Evans syndrome trilineage.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Imunoglobulinas Intravenosas/uso terapêutico , Esteroides/uso terapêutico , Trombocitopenia/diagnóstico , Adolescente , Assistência ao Convalescente , Anemia Hemolítica Autoimune/tratamento farmacológico , Anticorpos Anticitoplasma de Neutrófilos/análise , Teste de Coombs/métodos , Feminino , Humanos , Neutropenia/patologia , Trombocitopenia/tratamento farmacológico
4.
J Exp Bot ; 63(1): 471-88, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21976770

RESUMO

The genetic basis of stem cell specification in somatic embryogenesis and organogenesis is still obscure. SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) genes are involved in embryogenesis and organogenesis in numerous species. In vitro culture of Cyclamen persicum immature ovules provides a system for investigating stem cell formation and maintenance, because lines forming either organs or embryos or callus without organs/embryos are available for the same cultivar and plant growth regulator conditions. The present aim was to exploit this property of cyclamen cultures to understand the role of SERK(s) in stem cell formation and maintenance in somatic embryogenesis and organogenesis in vitro, in comparison with expression in planta. CpSERK1 and CpSERK2 were isolated from embryogenic callus. CpSERK1 and CpSERK2 levels by RT-PCR showed that expression is high in embryogenic, moderate in organogenic, and null in recalcitrant calli. in situ hybridizations showed that the expression of both genes started in clumps of pluripotent stem cells, from which both pre-embryogenic aggregates and organ meristemoids derived, and continued in their trans-amplifying, meristem-like, derivatives. Expression declined in organ meristemoids, in parallel with a partial loss of meristematization. In mature somatic embryos, and in shoot and root primordia, CpSERK1 and CpSERK2 were expressed in meristems, and similar patterns occurred in zygotic embryo and primary meristems in planta. The results point to SERK1 and SERK2 as markers of pluripotency in cyclamen. It is proposed that the high expression of these genes in the trans-amplifying derivatives of the stem cells maintains a pluripotent condition leading to totipotency and, consequently, somatic embryogenesis.


Assuntos
Cyclamen/genética , Marcadores Genéticos , Proteínas de Plantas/genética , Proteínas Quinases/genética , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas Quinases/química , Reação em Cadeia da Polimerase em Tempo Real , Homologia de Sequência de Aminoácidos
5.
Appl Radiat Isot ; 64(5): 624-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16413194

RESUMO

Soil radon has been monitored at a fixed location on the northeastern flank of Mt. Etna, a high-risk volcano in Sicily. The aim of this study was to evaluate the effects of the recent volcanic activity on soil radon concentration. Continuous radon measurements have been performed since July 2001. While comparison between the trend in in-soil radon concentration and the acquired meteorological series (temperature, humidity and pressure) appear to confirm a general seasonal correlation, nevertheless particular anomalies suggest a possible dependence of the radon concentration on volcanic dynamics.

6.
Apoptosis ; 11(1): 57-66, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16374542

RESUMO

Due to their ballistic precision, apoptosis induction by protons could be a strategy to specifically eliminate neoplastic cells. To characterize the cellular and molecular effects of these hadrons, we performed dose-response and time-course experiments by exposing different cell lines (PC3, Ca301D, MCF7) to increasing doses of protons and examining them with FACS, RT-PCR, and electron spin resonance (ESR). Irradiation with a dose of 10 Gy of a 26,7 Mev proton beam altered cell structures such as membranes, caused DNA double strand breaks, and significantly increased intracellular levels of hydroxyl ions, are active oxygen species (ROS). This modified the transcriptome of irradiated cells, activated the mitochondrial (intrinsic) pathway of apoptosis, and resulted in cycle arrest at the G2/M boundary. The number of necrotic cells within the irradiated cell population did not significantly increase with respect to the controls. The effects of irradiation with 20 Gy were qualitatively as well as quantitatively similar, but exposure to 40 Gy caused massive necrosis. Similar experiments with photons demonstrated that they induce apoptosis in a significantly lower number of cells and in a temporally delayed manner. These data advance our knowledge on the cellular and molecular effects of proton irradiation and could be useful for improving current hadrontherapy protocols.


Assuntos
Apoptose/efeitos da radiação , Neoplasias/radioterapia , Terapia com Prótons , Apoptose/genética , Sequência de Bases , Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Dano ao DNA , Primers do DNA/genética , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Citometria de Fluxo , Humanos , Masculino , Necrose , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Fótons/uso terapêutico , RNA Mensageiro/genética , RNA Neoplásico/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Radiat Prot Dosimetry ; 101(1-4): 453-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12382789

RESUMO

The aim of this work was to investigate the use of TLD-100 detectors in the field of relative dosimetry in proton eye facilities. These dosemeters, of different sizes, were used to measure transverse and longitudinal distributions of 62 MeV unmodulated proton beams at INFN-LNS in Catania. Comparison with other detectors, such as ionisation chambers, GAF and radiographic film, is extensively discussed.


Assuntos
Prótons , Dosimetria Termoluminescente/métodos , Calibragem , Valores de Referência , Reprodutibilidade dos Testes
9.
Phys Med Biol ; 45(10): 3045-58, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11049187

RESUMO

The dosimetric behaviour of a Scanditronix p-type silicon diode and a PTW natural diamond detector was studied in low-energy proton beams in the 8.3-21.5 MeV range. The properties investigated were linearity, reproducibility, dose rate dependence, energy and linear energy transfer (LET) dependence. The influence of detector thickness on the results of depth dose measurements was also demonstrated. A Markus parallel plate ionization chamber was used for reference dosimetry. Silicon diode and diamond detectors showed linearity at therapeutic dose level, reproducibility better than 1% (1sigma) and sensitivity variation with dose rate and proton energy.


Assuntos
Diamante , Prótons , Radiometria/instrumentação , Radiometria/métodos , Silício , Relação Dose-Resposta à Radiação , Íons , Imagens de Fantasmas , Água
10.
J Pathol ; 190(4): 423-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10699990

RESUMO

Mutant ras genes occur frequently in human neoplasia and, in particular, in pancreatic, colorectal, and lung adenocarcinomas. Recent evidence suggests that G-->T and G-->C transversions of the Ki-ras gene in codon 12 may lead to biological effects in vitro and in vivo that may be associated with an abnormal cell cycle and increased tumour aggressiveness. The role of Ki-ras activation (a G-->C transversion in codon 12, arginine for glycine) in the cell cycle and apoptosis was investigated using control and permanently transfected NIH3T3 mouse fibroblasts. Flow cytometry was used to evaluate the G1-, S- and G2M-phase transit times, the potential doubling time, the growth fraction, and the cell loss factor during asynchronous exponential growth. Apoptosis was induced in both cell lines by absence of growth factors for an extended period of time (72 h) and quantitatively evaluated using the TUNEL method coupled with flow cytometry. It was found that codon 12 G-->C Ki-ras transfected cells compared with controls, had a significant prolongation of G1 by about 50%, a reduction of the G2M transit time by 30%, and a decrease of the cell loss factor by about 90%. Apoptotic cells were about 10% in control and less than 0.5% in Ki-ras transfected cells after 72 h starvation-confluency. These data suggest that codon 12 G-->C Ki-ras activation in mouse NIH3T3 fibroblasts is associated with deregulation of checkpoint controls in the G1 and G2M phases of the cell cycle and inhibition of apoptosis. It appears plausible that these cell mechanisms are related to a proliferative advantage and that they may also be important in the progression of human tumours characterized by specific Ki-ras mutations.


Assuntos
Apoptose/genética , Regulação da Expressão Gênica/genética , Genes ras/genética , Interfase/genética , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Células 3T3 , Animais , Sondas de DNA , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Metáfase/genética , Camundongos , Transfecção
11.
Cancer ; 83(3): 415-22, 1998 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9690532

RESUMO

BACKGROUND: Cytogenetics and molecular biology studies have indicated that a large subset of human colorectal adenocarcinomas have distal 1p chromosome arm deletions. The aim of this study was to evaluate the intratumor distribution of 1p deletions under the assumption that homogeneity is an indication of early occurrence. METHODS: Seventy-nine histologically selected primary sectors (40 superficial and 39 deep) and 3 lymph node metastases obtained from 20 human sporadic adenocarcinomas were analyzed. Interphase two-color fluorescence in situ hybridization (FISH) was applied to cytocentrifuged nuclei using a centromeric probe for chromosome 1 and a telomeric probe mapping to the 1p36 band. RESULTS: Deletions at 1p were observed in 35 of 82 tumor samples corresponding to 9 of 20 adenocarcinomas analyzed (45%). Seven of the 9 adenocarcinomas with 1p deletions showed an intratumor presence of these aberrations in all the different tumor sectors. CONCLUSIONS: These data, acquired by FISH interphase cytogenetics, confirm that 1p deletions in colorectal adenocarcinoma are common and suggest that this structural chromosomal aberration occurs mainly as an early event in colorectal tumorigenesis.


Assuntos
Adenocarcinoma/genética , Deleção Cromossômica , Cromossomos Humanos Par 1 , Neoplasias Colorretais/genética , Adenocarcinoma/etiologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/etiologia , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade
12.
Anal Cell Pathol ; 17(2): 93-101, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10052633

RESUMO

A monoclonal antibody (AS-2) raised by using isolated nuclei from a human erythroleukemia cell line as immunogen is described. AS-2 was of IgM type and recognized proteins present in both isolated cytoplasms and nuclei. The molecular weight of the AS-2 recognized proteins in the cytoplasm was 200 kDa and 70 and 60 kDa in the nucleus. The relative amount of these proteins were measured simultaneously with DNA content by flow cytometry. We found the highest protein content (or stainability) for both cells and nuclei in late-G1, S and G2, at approximately the same level, and the lowest content in M and early-G1. Sorting based on DNA content and AS-2 associated fluorescence helped identifying the staining pattern of cells and nuclei. Interphase isolated nuclei and cell cytoplasms were characterized by interdispersed staining over the entire surfaces while mitoses showed two dots only. The present preliminary data indicate that the proteins recognized by the AS-2 monoclonal are cell cycle related and suggest that in mitoses they are associated with the centrosomes.


Assuntos
Anticorpos Monoclonais , Proteínas de Ciclo Celular/imunologia , Núcleo Celular/imunologia , Animais , Proteínas de Ciclo Celular/análise , Núcleo Celular/patologia , Feminino , Citometria de Fluxo/métodos , Imunofluorescência , Células HeLa , Humanos , Células K562/imunologia , Células K562/patologia , Camundongos , Camundongos Endogâmicos BALB C
13.
Int J Cancer ; 67(6): 871-5, 1996 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-8824561

RESUMO

The aim of the study was to test the hypothesis that a human mutated K-ras protein induces abnormalities in mitosis and development of sub-clones characterized by changes in DNA ploidy and proliferation. For this purpose, we used control and NIH-3T3 mouse cells transfected with the human codon 12 G-C-mutated K-ras oncogene. We found that abnormal mitoses, mainly characterized by lagging chromosomes in prometaphase or anaphase, had a significantly higher frequency in transfected cells than in control cells. The generation of sub-clones was screened by limiting-dilution experiments followed by cell expansion. Cloning efficiency was much higher for the K-ras transfected cells with 858/2112 (41%) successful sub-clones than for control, which provided 564/2592 (22%) sub-clones. DNA flow cytometry of 4.6-diamidino-2-phenilindole-2-hydrochloride-stained nuclei from randomly selected sub-clones was performed in order to evaluate DNA index and S-phase fraction values. We found 9 out of 100 DNA aneuploid sub-clones generated by the K-ras-transfected cells vs. 1 out of 100 for the controls. Overall, our data indicate that high expression of the mutationally activated human K-ras product in NIH-3T3 cells was associated with abnormal mitoses, increase of cloning efficiency and DNA aneuploidization.


Assuntos
Células 3T3/patologia , Aneuploidia , Genes ras/genética , Mutação Puntual , Proteínas Proto-Oncogênicas p21(ras)/genética , Transfecção , Animais , Divisão Celular/genética , Humanos , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
14.
Am J Pathol ; 149(1): 237-45, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8686748

RESUMO

Detailed information about intratumor K-ras2 mutations in colorectal adenocarcinomas and a possible association with DNA content heterogeneity is still lacking. DNA diploid and aneuploid subclones, detected among multiple histologically selected primary sectors (57 superficial and 40 deep) and 9 lymph node metastases, were flow cytometrically sorted and separately submitted to codons 12-13 K-ras2 mutation spectrum analysis. DNA aneuploidy was absent among 20 near and 20 distant mucosa sites and present in 7/9 lymph node metastases and in 17/19 primary tumors (90%). Primary intratumor DNA multiclonality was approximately 50%. Degree of DNA aneuploidy (DNA Index) distribution was nonrandom and showed peaks at approximate mean DNA Index values 1.2, 1.5, and 1.8. K-ras2 mutations were detected in 0/20 mucosa cases, in 2/9 lymph node metastases, and in 9/19 adenocarcinomas (47%). No more than one mutation type per tumor was detected. Intratumor distribution of K-ras2 mutations was homogeneous in 6 and heterogeneous in 3 cases. Homogeneous distribution was associated with DNA near-diploid aneuploidy. K-ras2 mutations were strongly associated with DNA Index in the near-diploid region (83%) and almost absent (5%) among DNA near-triploid subclones (P = 0.0001). K-ras2 mutation intratumor heterogeneity indicates that sampling of the tumor may be a critical step and suggests that K-ras2 activation may be a late event in a subgroup of tumors. Our data also suggest the existence of an early process of the colorectal carcinogenesis that favors both K-ras2 mutations and DNA near-diploid aneuploidy. Onset of DNA near-triploid subclones appears, instead, to be independent from K-ras2 activation.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , DNA de Neoplasias/isolamento & purificação , Genes ras/genética , Mutação Puntual , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Clonagem Molecular , Neoplasias Colorretais/patologia , Citometria de Fluxo , Humanos , Metástase Linfática , Ploidias , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
15.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 42(2): 123-6, abr.-jun. 1996. ilus
Artigo em Português | LILACS | ID: lil-180128

RESUMO

Os autores apresentam um caso de carcinoma do testículo (CT) nao-seminoma (NS) num jovem índio Xikrin, Caiapó setentrional, do sudeste do Pará, na Amazônia oriental. RELATO DE CASO. O índio desenvolveu uma metásase supraclavicular vegetante à esquerda com evoluçao progressiva num prazo de cinco meses. No exame físico, após sua remoçao a Sao Paulo, observaram que o testículo direito era tumoral. Os exames laboratoriais mostraram alfa-fetoproteína (AFP) l82U/mL, gonadotropina coriônica fraçao (beta-HCG) 43mUI/mL. O exame anatomopatológico da metástase supraclavicular foi de carcinoma embrionário e o anatomopatológico do testículo direio foi de carcinoma NS, embrionário, com áreas de teratoma maduro. Foi submetido à ressecçao cirúrgica parcial da metástase supraclavicular, à retirada cirúrgica do testículo tumoral, a três ciclos de quimioterapia. A AFP e a beta-HCG normalizaram-se após a quimioterapia. DISCUSSAO E CONCLUSAO. No mundo há registro de aumento da incidência de carcinomas germinativos entre caucasóides. O interesse desta apresentaçao está no fato de ser a primeira incidência de carcinoma diferenciado, NS, no grupo étnico de índios brasileiros e na boa evoluçao do caso, apesar de o diagnóstico ter sido estabelecido tardiamente.


Assuntos
Humanos , Masculino , Adolescente , Teratoma/diagnóstico , Neoplasias Testiculares/diagnóstico , Carcinoma Embrionário/diagnóstico , Clavícula , Indígenas Sul-Americanos , Teratoma/terapia , Neoplasias Testiculares/patologia , Neoplasias Testiculares/terapia , Brasil , Carcinoma Embrionário/patologia , Carcinoma Embrionário/terapia
16.
Rev Assoc Med Bras (1992) ; 42(2): 123-6, 1996.
Artigo em Português | MEDLINE | ID: mdl-9110463

RESUMO

UNLABELLED: The authors present a case of non-seminoma (NS) carcinoma of the testis (CT) in a young Xikrin indian, from northern Caiapó, southeast Pará, in eastern Amazonia. CASE REPORT: The patient developed a left vegetative supraclavicular metastasis with progressive evolution during 5 months. After being brought to São Paulo, a right tumoral testis was observed on physical examination. The laboratory tests showed alpha-feto protein (AFP) 182 U/mL, beta-chorionic gonadotrophin (beta-HCG) 43 mIU/mL. The result of the anatomopathological examination of the supraclavicular metastasis was embryonic carcinoma and that of the right testis was NS, embryonic carcinoma with mature teratoma areas. The patient was submitted to partial surgery of the supraclavicular metastasis and removal of the tumoral testis, followed by three cycles of chemotherapy. After the latter, AFP and beta-HCG returned to normal. DISCUSSION AND CONCLUSION: There is a world-wide record of increase in the incidence of germinative carcinomas among Caucasoids. The interest of the presentation of this case lies in the fact that it is the first incidence of differentiated carcinoma, NS, in the ethnic group of Brazilian indians and also its good evolution in spite of a late diagnosis.


Assuntos
Carcinoma Embrionário/secundário , Neoplasias de Cabeça e Pescoço/secundário , Indígenas Sul-Americanos , Neoplasias Primárias Múltiplas , Teratoma , Neoplasias Testiculares/patologia , Adolescente , Brasil , Carcinoma Embrionário/diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Masculino , Neoplasias Primárias Múltiplas/diagnóstico , Teratoma/diagnóstico
18.
Gastroenterology ; 108(4): 1040-7, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7698570

RESUMO

BACKGROUND/AIMS: K-ras-2 mutations and DNA content heterogeneity represent early events of human colorectal tumor progression. The aim of the study was to investigate if specific K-ras-2 mutations in 58 human sporadic adenomas were correlated with DNA aneuploidization and cell proliferation. METHODS: Multiparameter flow cytometry, based on scatter parameters and DNA content, was performed using 4,6-diamidino-2-phenilindole-2-hydrochloride-stained nuclei obtained from adenoma fragments with either mild-moderate or severe dysplasia. K-ras-2 polymerase chain reaction and spectrum analysis were performed using sorted DNA specific epithelial subclones. RESULTS: We detected six G-A transitions, and four G-C and two G-T transversions. The DNA aneuploid subclones were 25 with DNA index values in the near diploid region (DNA index < 1.3) for the vast majority of cases (80%). DNA aneuploidy among the mutated adenomas with G-A transitions was 1 of 6 (17%) and 6 of 6 (100%) among G-C and G-T transversions. Although DNA aneuploidy and high S-phase values were also present among K-ras-2 wild-type adenomas, their statistical associations with K-ras-2 status were P < 0.005 and P < 0.05, respectively. CONCLUSIONS: The present series of sporadic colorectal adenomas indicates that codon 12 G-C and G-T K-ras-2 transversion mutations and DNA aneuploidy are correlated. The underlying mechanisms that explain such association remain to be investigated.


Assuntos
Adenoma/genética , Aneuploidia , Neoplasias Colorretais/genética , DNA de Neoplasias/genética , Genes ras/genética , Mutação Puntual , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Códon , Neoplasias Colorretais/patologia , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Fase S
19.
Int J Oncol ; 7(5): 1213-7, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21552953

RESUMO

N-(4-Hydroxyphenyl)retinamide (HPR) is a synthetic retinoid with anticancer properties and lower toxicity than all-trans retinoic acid (RA). We have studied the effects of HPR on apoptosis and differentiation in the human promyelocytic leukemia HL-60 cell line. In addition, we have tested the hypothesis that vimentin expression after HPR and RA, taken as indirect evidence of the mechanisms of action of the two retinoids, may be different. Quantitative evaluation of the percentage of apoptotic cells was carried out on a cell by cell basis by the flow cytometric DNA-content in situ-terminal-deoxynucleotydil-transferase (TdT assay). HPR was found to clearly induce apoptosis, while RA: instead, induced differentiation without apoptosis. These data confirm previous observations. Vimentin protein content was evaluated by flow cytometry with use of monoclonal antibodies simultaneously with DNA content. We found that HPR treated apoptotic cells were characterized by negative vimentin expression, while the HPR treated non apoptotic cells had about the same level of vimentin as the RA treated cells. These latter findings suggest that HPR may induce a functional effect (apoptosis) by a mechanism of action different from that of RA. Further work is necessary to clarify this finding.

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