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1.
BMC Cancer ; 20(1): 16, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906955

RESUMO

BACKGROUND: Improved, multimodal treatment strategies have been shown to increase cure rates in cancer patients. Those who survive cancer as a child, adolescent or young adult (CAYA), are at a higher risk for therapy-, or disease-related, late or long-term effects. The CARE for CAYA-Program has been developed to comprehensively assess any potential future problems, to offer need-based preventative interventions and thus to improve long-term outcomes in this particularly vulnerable population. METHODS: The trial is designed as an adaptive trial with an annual comprehensive assessment followed by needs stratified, modular interventions, currently including physical activity, nutrition and psycho-oncology, all aimed at improving the lifestyle and/or the psychosocial situation of the patients. Patients, aged 15-39 years old, with a prior cancer diagnosis, who have completed tumour therapy and are in follow-up care, and who are tumour free, will be included. At baseline (and subsequently on an annual basis) the current medical and psychosocial situation and lifestyle of the participants will be assessed using a survey compiled of various validated questionnaires (e.g. EORTC QLQ C30, NCCN distress thermometer, PHQ-4, BSA, nutrition protocol) and objective parameters (e.g. BMI, WHR, co-morbidities like hyperlipidaemia, hypertension, diabetes), followed by basic care (psychological and lifestyle consultation). Depending on their needs, CAYAs will be allocated to preventative interventions in the above-mentioned modules over a 12-month period. After 1 year, the assessment will be repeated, and further interventions may be applied as needed. During the initial trial phase, the efficacy of this approach will be compared to standard care (waiting list with intervention in the following year) in a randomized study. During this phase, 530 CAYAs will be included and 320 eligible CAYAs who are willing to participate in the interventions will be randomly allocated to an intervention. Overall, 1500 CAYAs will be included and assessed. The programme is financed by the innovation fund of the German Federal Joint Committee and will be conducted at 14 German sites. Recruitment began in January 2018. DISCUSSION: CAYAs are at high risk for long-term sequelae. Providing structured interventions to improve lifestyle and psychological situation may counteract against these risk factors. The programme serves to establish uniform regular comprehensive assessments and need-based interventions to improve long-term outcome in CAYA survivors. TRIAL REGISTRATION: Registered at the German Clinical Trial Register (ID: DRKS00012504, registration date: 19th January 2018).


Assuntos
Assistência ao Convalescente/métodos , Sobreviventes de Câncer/psicologia , Adolescente , Adulto , Assistência ao Convalescente/organização & administração , Criança , Depressão/psicologia , Depressão/terapia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Exercício Físico/fisiologia , Feminino , Humanos , Estilo de Vida , Masculino , Neoplasias/complicações , Neoplasias/psicologia , Avaliação Nutricional , Medicina Preventiva/métodos , Medicina Preventiva/organização & administração , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Adulto Jovem
2.
Phys Chem Chem Phys ; 18(9): 6668-75, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26871757

RESUMO

A new cyano substituted bis(terpyridine) derivative CN-BTP was synthesized and its adsorption on highly oriented pyrolytic graphite (HOPG) and Au(111) was investigated. CN-BTP is closely related to the previously investigated 2,4'-BTP, where the cyanophenyl groups are replaced by pyridine moieties. The scanning tunneling microscopy (STM) investigation of CN-BTP at the liquid|HOPG interface shows a highly ordered herringbone structure that is stabilized by double weak intermolecular C-HN hydrogen bonds, partially through the -CN substituents, which is different from the most stable square structure of 2,4'-BTP. The adsorption processes were investigated using cyclic voltammetry (CV) on Au(111) in a neutral phosphate buffer. A fast and full adlayer formation could be observed with CN-BTP, whereas an extremely slow process with 2,4'-BTP under the same conditions was found. Our data show that the CN substituents on BTP not only change the structure of the monolayer at the liquid|HOPG interface, but also accelerate the phase transition process in the electrolyte dramatically. This could be explained by the adlayer-substrate interactions, which is supported by DFT calculations. Our findings might be extended more generally to further pyridine comprising self-assembling molecules to fine-tune the adlayer structure and phase transition/adsorption kinetics by replacing pyridine by cyanophenyl moieties.

3.
Nat Genet ; 16(1): 44-53, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9140394

RESUMO

Huntington disease (HD) is associated with the expansion of a polyglutamine tract, greater than 35 repeats, in the HD gene product, huntingtin. Here we describe a novel huntingtin interacting protein, HIP1, which co-localizes with huntingtin and shares sequence homology and biochemical characteristics with Sla2p, a protein essential for function of the cytoskeleton in Saccharomyces cerevisiae. The huntingtin-HIP1 interaction is restricted to the brain and is inversely correlated to the polyglutamine length in huntingtin. This provides the first molecular link between huntingtin and the neuronal cytoskeleton and suggests that, in HD, loss of normal huntingtin-HIP1 interaction may contribute to a defect in membrane-cytoskeletal integrity in the brain.


Assuntos
Encéfalo/fisiologia , Proteínas de Transporte/genética , Proteínas de Ligação a DNA/genética , Proteínas Fúngicas/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Animais , Western Blotting , Encéfalo/citologia , Caenorhabditis elegans/química , Caenorhabditis elegans/genética , Proteínas de Transporte/metabolismo , Sistema Nervoso Central/metabolismo , Mapeamento Cromossômico , Cromossomos Humanos Par 7 , Clonagem Molecular , Proteínas do Citoesqueleto , Proteínas de Ligação a DNA/imunologia , Proteínas de Ligação a DNA/metabolismo , Feminino , Proteínas de Helminto/genética , Humanos , Proteína Huntingtina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/imunologia , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Peptídeos/química , Peptídeos/metabolismo , Testes de Precipitina , Coelhos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade , Frações Subcelulares , Distribuição Tecidual
4.
Arch Toxicol ; 86(4): 643-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22143556

RESUMO

For studies on the aryl hydrocarbon receptor (AhR)-dependent toxicity of the mycotoxins alternariol (AOH) and alternariol methyl ether (AME), three mouse hepatoma (Hepa-1) cell lines with intact and with compromised AhR signaling were compared with respect to their activities for hydroxylation, methylation, and glucuronidation. Whereas the activities of cytochrome P450-mediated monooxygenase and catechol-O-methyl transferase were very low and did not differ between the three cell lines, a pronounced difference was observed for UDP-glucuronosyl transferase activity, which was much higher in Hepa-1c1c4 than in c1c7 and c1c12 cells. In all three cell types, the rate of glucuronidation of AOH was about four times higher than that of AME. Whereas AME caused a concentration-dependent G2/M arrest in each cell line, AOH arrested Hepa-1c1c7 and c1c12 cells but not c1c4 cells. However, Hepa-1c1c4 cells were arrested by AOH when ß-glucuronidase was added to the incubation medium in order to reverse the formation of AOH glucuronides. We conclude that the failure of AOH to cause cell cycle inhibition in Hepa-1c1c4 cells is due to its efficient glucuronidation. The considerable UDP-glucuronosyl transferase activity of Hepa-1c1c4 cells should be taken into account when other compounds are studied in this cell line. Moreover, we demonstrate that differences in glucuronide formation between cell types can be overcome by the addition of ß-glucuronidase to the cell culture medium.


Assuntos
Carcinoma Hepatocelular/metabolismo , Glucuronídeos/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Carcinoma Hepatocelular/tratamento farmacológico , Catecol O-Metiltransferase/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quimioterapia Combinada , Glucuronidase/farmacologia , Glucuronosiltransferase/metabolismo , Hepatócitos/efeitos dos fármacos , Lactonas/toxicidade , Neoplasias Hepáticas/tratamento farmacológico , Camundongos , Micotoxinas/toxicidade , Receptores de Hidrocarboneto Arílico/efeitos dos fármacos , Transdução de Sinais
5.
Klin Padiatr ; 224(3): 170-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22513792

RESUMO

Malignant peritoneal mesothelioma is extremely rarely seen in young patients.A 16 year-old girl presented with appendicitis-like acute abdominal pain. Intra-operatively, multiple confluent peritoneal nodules were seen on the entire greater omentum and in the pelvis infiltrating the uterus and both ovaries. Biopsies were obtained and interpreted as serous ovarian carcinoma. Radical surgical resection and hyperthermic intraperitoneal chemotherapy -(HIPEC) with carboplatin was performed and followed by 2 cycles of carboplatin/paclitaxel. Histological reevaluation showed characteristic features of epithelioid peritoneal mesothelioma and ruled out serous ovarian cancer. Therapy was continued with 6 cycles of pemetrexed/cisplatin.3 months after end of chemotherapy vital tumor tissue was found in the recess behind the liver, which could be resected completely. The patient is currently disease-free 17 months after initial diagnosis.Malignant peritoneal mesothelioma in young female patients might be under-recognized and possibly misdiagnosed as ovarian serous carcinoma in some cases. International and interdisciplinary cooperation is necessary in order to provide evidence based guidelines for diagnosis and treatment in the future.


Assuntos
Mesotelioma/diagnóstico , Neoplasias Peritoneais/diagnóstico , Doenças Raras , Dor Abdominal/etiologia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Quimioterapia do Câncer por Perfusão Regional , Terapia Combinada , Diagnóstico Diferencial , Feminino , Humanos , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Mesotelioma/cirurgia , Paclitaxel/administração & dosagem , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/cirurgia
6.
Klin Padiatr ; 224(3): 124-31, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22522984

RESUMO

Although prognosis of children with solid tumors is steadily improving, long-term survival is not achievable in all patients, especially in patients with recurrent or refractory disease. Despite the increasing number of targeted therapeutics (TT), only very few TT have been introduced into clinical protocols. Accordingly, clinical experience concerning the efficacy and safety of these drugs is limited. This may possibly discourage oncologists from administering TT to children.We performed a comprehensive review of the literature to identify TT that may be considered for treatment of children and young adults with solid tumors. Moreover, we interviewed an expert panel of the Society for Pediatric Oncology and Hematology (GPOH) using questionnaires in a modified Delphi process in order to describe the experts' experiences in the use of these TT.Among 30 TT identified to be possibly useful in children and young adults, imatinib, bevacizumab and rapamycin were most widely used. These drugs were reported as having mostly little to no severe adverse events and seem to induce at least partial responses in a subset of patients. In addition, our study confirms and expands the present knowledge about adverse events and the potential efficacy of 5 other commonly used TT in this population.This information may be useful for oncologists when administering these TT to children and young adults with solid tumors. Controlled clinical trials are urgently needed to test their safety and efficacy.


Assuntos
Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Adolescente , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/toxicidade , Benzamidas , Bevacizumab , Criança , Técnica Delphi , Humanos , Mesilato de Imatinib , Piperazinas/uso terapêutico , Piperazinas/toxicidade , Pirimidinas/uso terapêutico , Pirimidinas/toxicidade , Sirolimo/uso terapêutico , Sirolimo/toxicidade , Adulto Jovem
7.
J Synchrotron Radiat ; 17(4): 451-5, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20567076

RESUMO

Micro-fabricated bi-prisms have been used to create an interference pattern from an incident hard X-ray beam, and the intensity of the pattern probed with fluorescence from a 30 nm-thick metal film. Maximum fringe visibility exceeded 0.9 owing to the nano-sized probe and the choice of single-crystal prism material. A full near-field analysis is necessary to describe the fringe field intensities, and the transverse coherence lengths were extracted at APS beamline 8-ID-I. It is also shown that the maximum number of fringes is dependent only on the complex refractive index of the prism material.

8.
Xenobiotica ; 40(1): 72-82, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20001673

RESUMO

The in vitro mammalian metabolism of the fungicide zoxamide is related to its in vitro mammalian toxicity. After incubation of zoxamide with rat liver microsomes leading to practically 100% metabolism (mostly hydroxylated zoxamide), the cytotoxicity (methyl thiazole tetrazolium (MTT) test) and the mitosis-inhibiting potential (shown by cell count and by cell cycle analysis) for V79 were not distinguishable from those of zoxamide, demonstrating that the hydroxylation of zoxamide did not change the cytotoxicity or mitosis-inhibiting potential as determined by these assays. After incubation of zoxamide with rat liver S9 predominantly leading to conjugation with glutathione, and after incubation of zoxamide with rat liver slices predominantly leading to the glucuronide of the hydroxylated zoxamide, these activities were eliminated demonstrating that the glutathione conjugate and the glucuronide had lost the activities in these assays due either to no intrinsic potential of these conjugates or to their inability to penetrate the plasma membrane of mammalian cells. It is concluded that the metabolic hydroxylation of zoxamide did not change its activity in the assays used for investigating its influence on cell proliferation, cell cycle and cytotoxicity, while the formation of conjugates with glutathione or glucuronic acid led to the apparent loss of these activities. Thus, with zoxamide as a prototype, it was shown that, in principle, mammalian metabolism and its relationship to mammalian detoxication of fungicidal mitosis inhibitors may be reasonably anticipated from in vitro studies. In addition, the results provide a rational for the observed absence of typically mitosis inhibition-associated toxicities of zoxamide in mammals in vivo.


Assuntos
Amidas/metabolismo , Amidas/toxicidade , Fungicidas Industriais/metabolismo , Fungicidas Industriais/toxicidade , Mitose/efeitos dos fármacos , Animais , Linhagem Celular , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Humanos , Hidroxilação , Fígado/efeitos dos fármacos , Fígado/metabolismo , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Ratos , Transfecção
9.
J Cell Biol ; 141(5): 1097-105, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9606203

RESUMO

Huntington disease is an autosomal dominant neurodegenerative disorder caused by the pathological expansion of a polyglutamine tract. In this study we directly assess the influence of protein size on the formation and subcellular localization of huntingtin aggregates. We have created numerous deletion constructs expressing successively smaller fragments of huntingtin and show that these smaller proteins containing 128 glutamines form both intranuclear and perinuclear aggregates. In contrast, larger NH2-terminal fragments of huntingtin proteins with 128 glutamines form exclusively perinuclear aggregates. These aggregates can form in the absence of endogenous huntingtin. Furthermore, expression of mutant huntingtin results in increased susceptibility to apoptotic stress that is greater with decreasing protein length and increasing polyglutamine size. As both intranuclear and perinuclear aggregates are clearly associated with increased cellular toxicity, this supports an important role for toxic polyglutamine-containing fragments forming aggregates and playing a key role in the pathogenesis of Huntington disease.


Assuntos
Apoptose , Doença de Huntington/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/metabolismo , Animais , Linhagem Celular , Núcleo Celular , Humanos , Proteína Huntingtina , Camundongos , Peso Molecular , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/fisiologia , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia
10.
Oncogene ; 25(22): 3093-103, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16607274

RESUMO

MLL-AF4 fusion is the most common consequence of chromosomal translocations in infant leukaemia and is associated with a poor prognosis. MLL-AF4 is thought to be required in haematopoietic stem cells to elicit leukaemia and may be involved in tumour phenotype specification as it is only found in B-cell tumours in humans. We have employed the invertor conditional technology to create a model of MLL-AF4, in which a floxed AF4 cDNA was knocked into Mll in the opposite orientation for transcription. Cell-specific Cre expression was used to generate Mll-AF4 expression. The mice develop exclusively B-cell lineage neoplasias, whether the Cre gene was controlled by B- or T-cell promoters, but of a more mature phenotype than normally observed in childhood leukaemia. These findings show that the MLL-AF4 fusion protein does not have a mandatory role in multi-potent haematopoietic stem cells to cause cancer and indicates that MLL-AF4 has an instructive function in the phenotype of the tumour.


Assuntos
Linfócitos B/patologia , Linhagem da Célula , Transformação Celular Neoplásica , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Proteína de Leucina Linfoide-Mieloide/fisiologia , Proteínas de Fusão Oncogênica/fisiologia , Animais , Linfócitos B/metabolismo , Feminino , Genes Letais , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Humanos , Integrases/metabolismo , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Fenótipo , Linfócitos T/metabolismo , Linfócitos T/patologia
11.
J Perinatol ; 37(6): 668-672, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28252659

RESUMO

OBJECTIVE: To determine whether systemic inflammation-modulating cytokine expression is related to heart rate variability (HRV) in newborns with hypoxic-ischemic encephalopathy (HIE). STUDY DESIGN: The data from 30 newborns with HIE were analyzed. Cytokine levels (IL-2, IL-4, IL-6, IL-8, IL-10, IL-13, IL-1ß, TNF-α, IFN-λ) were measured either at 24 h of cooling (n=5), 72 h of cooling (n=4) or at both timepoints (n=21). The following HRV metrics were quantified in the time domain: alpha_S, alpha_L, root mean square (RMS) at short time scales (RMS_S), RMS at long time scales (RMS_L), while low-frequency power (LF) and high-frequency power (HF) were quantified in the frequency domain. The relationships between HRV metrics and cytokines were evaluated using mixed-models. RESULT: IL-6, IL-8, IL-10, and IL-13 levels were inversely related to selected HRV metrics. CONCLUSION: Inflammation-modulating cytokines may be important mediators in the autonomic dysfunction observed in newborns with HIE.


Assuntos
Citocinas/sangue , Frequência Cardíaca , Hipóxia-Isquemia Encefálica/sangue , Inflamação/sangue , Biomarcadores/sangue , Bradicardia/etiologia , Eletrocardiografia , Feminino , Humanos , Hipóxia-Isquemia Encefálica/complicações , Recém-Nascido , Masculino , Estudos Prospectivos , Análise de Regressão
12.
J Perinatol ; 37(12): 1278-1284, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28837138

RESUMO

OBJECTIVE: The relationship between placental and fetal brain growth is poorly understood and difficult to assess. The objective of this study was to interrogate placental and fetal brain growth in healthy pregnancies and those complicated by fetal growth restriction (FGR). STUDY DESIGN: In a prospective, observational study, pregnant women with normal pregnancies or pregnancies complicated by FGR underwent fetal magnetic resonance imaging (MRI). Placental, global and regional brain volumes were calculated. RESULTS: A total of 114 women (79 controls and 35 FGR) underwent MRI (median gestational age (GA) 30 weeks, range 18 to 39). All measured volumes increased exponentially with advancing GA. Placental, total brain, cerebral and cerebellar volumes were smaller in FGR compared with controls (P<0.05). Increasing placental volume was associated with increasing cerebral and cerebellar volumes (P<0.05). CONCLUSION: Quantitative fetal MRI can accurately detect decreased placental and brain volumes in pregnancies with FGR and may provide insight into the timing and mechanisms of brain injury in FGR.


Assuntos
Encéfalo/diagnóstico por imagem , Desenvolvimento Fetal , Retardo do Crescimento Fetal/diagnóstico por imagem , Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Placenta/diagnóstico por imagem , Adolescente , Adulto , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Estudos Longitudinais , Masculino , Tamanho do Órgão , Placenta/patologia , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos , Ultrassonografia Pré-Natal , Adulto Jovem
13.
J Perinatol ; 37(5): 558-562, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28079874

RESUMO

OBJECTIVE: Central topography of autonomic nervous system (ANS) function has yet to be fully deciphered. In adults it has been shown to lateralize sympathetic and parasympathetic influence predominantly to the right and left cerebral hemispheres, respectively. We examined functional topography of central ANS in newborn subjects utilizing spectral analysis of heart rate variability (HRV), an established measure of ANS function. STUDY DESIGN: We studied newborns with hypoxic-ischemic encephalopathy participating in a prospective study undergoing a therapeutic hypothermia protocol.We included subjects with continuous heart rate data over the first 3 h of normothermia (post rewarming) and brain magnetic resonance imaging, which was reviewed and scored according to a 4 region scheme. HRV was evaluated by spectral analysis in the low-frequency (0.05 to 0.25 Hz) and high-frequency (0.3 to 1 Hz) ranges. The relationship between injured brain regions and HRV was studied using multiple regressions. RESULTS: Forty eight newborns were included. When examined in isolation, right hemisphere injury had a significant negative effect on HRV (-0.088; 95% CI: -0.225,-0.008). The combination of posterior fossa region injury with right hemispheric injury or left hemispheric injury demonstrated significant positive (0.299; 95% CI: 0.065, 0.518) and negative (-0.475; 95% CI: -0.852, -0.128) influences on HRV, respectively. The association between brain injury location and HRV in the high-frequency range did not reach significance. CONCLUSION: Our data support the notion that lateralized cerebral modulation of the ANS, specifically of its sympathetic component, is present in the term newborn, and suggest complex modulation of these tracts by components of the posterior fossa.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Encéfalo/fisiopatologia , Frequência Cardíaca/fisiologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Hipóxia-Isquemia Encefálica/terapia , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Hipotermia Induzida , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Análise de Regressão , Nascimento a Termo
15.
17.
Food Chem Toxicol ; 44(3): 398-408, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16194592

RESUMO

The mycotoxin alternariol (AOH) is found in food and beverages infected by Alternaria alternata. Because consumption of foodstuffs contaminated with A. alternata has been implicated in an elevated incidence of esophageal carcinogenesis, we have investigated the estrogenic potential, the effect on cell proliferation, and the genotoxic effect of AOH in cultured mammalian cells. AOH replaced E2 from isolated human estrogen receptors alpha and beta and increased the level of alkaline phosphatase (ALP) mRNA and the enzymatic activity of ALP in a human endometrial adenocarcinoma cell line (Ishikawa cells). The estrogenicity of AOH was about 0.01% of that of E2. The effects in Ishikawa cells were reversed by the ER antagonist ICI 182,780. Analysis of cell proliferation by flow cytometry and microscopy of Ishikawa and Chinese hamster V79 cells revealed that AOH inhibited cell proliferation by interference with the cell cycle. The genotoxic potential was assessed by the micronucleus (MN) assay and immunochemical differentiation between MN containing whole chromosomes (kinetochore-positive) and DNA fragments (kinetochore-negative) in Ishikawa and V79 cells. AOH induced kinetochore-negative MN in both cell lines. This is the first report on the estrogenic potential, inhibition of cell proliferation and clastogenicity of AOH in Ishikawa and V79 cells in vitro.


Assuntos
Fosfatase Alcalina/biossíntese , Divisão Celular/efeitos dos fármacos , Inibidores da Colinesterase/toxicidade , Estrogênios/metabolismo , Lactonas/toxicidade , Mutagênicos/toxicidade , Adenocarcinoma/enzimologia , Adenocarcinoma/metabolismo , Alternaria/metabolismo , Animais , Linhagem Celular Tumoral , Aberrações Cromossômicas , Cricetinae , Cricetulus , Relação Dose-Resposta a Droga , Neoplasias do Endométrio/enzimologia , Neoplasias do Endométrio/metabolismo , Indução Enzimática , Neoplasias Esofágicas/induzido quimicamente , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Citometria de Fluxo , Contaminação de Alimentos , Humanos , Masculino , Testes para Micronúcleos , RNA Mensageiro/metabolismo
18.
Cancer Res ; 48(19): 5460-5, 1988 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-3416302

RESUMO

The influence of alpha-naphthoflavone (ANF) on the metabolism and binding of radiolabeled ethinylestradiol (EE2) has been examined both in vitro and in vivo in hamster liver microsomes. [14C]EE2 was metabolized extensively to seven major oxidative metabolites, 7 alpha-hydroxyEE2, 4-hydroxyEE2, 2-hydroxyEE2, D-homoestrone, monohydroxyEE2, and two dihydroxyEE2 metabolites identified as catechols with the additional hydroxy group on ring B or C, and a nonpolar fraction. The main EE2 metabolite found was 2-hydroxyEE2, and it represented 47% of the total metabolites formed. The total amount of EE2 catechol metabolites formed in untreated hamster liver microsomes was 65.5%. When ANF was added in vitro to these hepatic microsomes, there was a 27-45% decline in 2-hydroxyEE2 formation, a 98% reduction in dihydroxyEE2 (catechol-2), and a 56-66% reduction in the nonpolar fraction. The marked inhibition of EE2 metabolism by the in vitro addition of ANF is reflected by a corresponding decrease in the irreversible binding of radioactive hormone to hamster liver microsomal proteins. In contrast, a biphasic response of ANF on EE2 metabolism was observed after in vivo administration for 2.0 and 4.0 months. After 2.0 months of ANF treatment, there was a modest decline in all [14C]EE2 metabolites, except 2-hydroxyEE2 and dihydroxyEE2 (catechol 1). After 4.0 months of ANF treatment, the reduction in EE2 metabolism was even lower than after 2.0 months of treatment. Most interestingly, there was a 1.5-fold increase in 2-hydroxyEE2 after 4.0 months of ANF treatment, representing nearly 69% of the total EE2 metabolites formed. These results are consistent with an increase in irreversible binding of [14C]EE2 metabolites to hamster liver microsomal proteins after 4.0 months of ANF treatment. The relative 1.3-fold and the absolute 1.5-fold increases in 2-hydroxyEE2 after 2.0 and 4.0 months of ANF treatment in vivo, respectively, suggest that the elevation in this reactive EE2 metabolite precursor may contribute importantly to hepatotumorigenesis in the hamster following prolonged EE2 plus ANF treatment.


Assuntos
Benzoflavonas/farmacologia , Etinilestradiol/metabolismo , Flavonoides/farmacologia , Neoplasias Hepáticas/induzido quimicamente , Microssomos Hepáticos/metabolismo , Animais , Cricetinae , Mesocricetus , Microssomos Hepáticos/efeitos dos fármacos , Modelos Biológicos
19.
Biochim Biophys Acta ; 1305(3): 130-4, 1996 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8597597

RESUMO

To isolate promoters from Clavibacter xyli subsp. cynodontis (C. xyli subsp. cynodontis), we constructed a new promoter probe plasmid and made a C. xyli subsp. cynodontis promoter probe library. Two promoters gave over 2500-times stronger expression than the parental plasmid. The promoters were sequenced and compared to other bacterial promoters. These C. xyli subsp. cynodontis promoter regions are GC-rich and do not resemble E. coli promoters, but do resemble a few individual promoters found in streptomycetes.


Assuntos
Actinomycetales/genética , DNA Bacteriano/isolamento & purificação , Regiões Promotoras Genéticas , Sequência de Bases , Sequência Consenso , DNA Bacteriano/genética , Escherichia coli/genética , Bactérias Gram-Positivas/genética , Dados de Sequência Molecular , Plasmídeos , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Streptomyces/genética , Transformação Bacteriana
20.
Biochim Biophys Acta ; 838(3): 321-8, 1985 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-3970973

RESUMO

The metabolic energy source used by the pig red cell, which is unable to metabolize blood-borne glucose, was examined. Potential physiological substrates include adenosine, inosine, ribose, deoxyribose, dihydroxyacetone and glyceraldehyde, of which inosine was previously implicated. A net ATP synthesis by red cells occurs during in situ perfusion through the adult miniature pig liver. HPLC analysis of the perfusate revealed the presence primarily of inosine and hypoxanthine. Inosine production by the liver was 0.015 mumol/g per min. Moreover, red cells maintain ATP when suspended in a balanced salt medium during a 6 h incubation at 38 degrees C, in which inosine is continuously infused to give an external concentration of no more than 3 mumol/l, mimicking its plasma level. Inosine consumption under these infusion conditions was 56 nmol/ml cell per h, which is two orders of magnitude lower than when inosine is present in millimolar concentration. The total red cell inosine consumption of 9.63 mumol/h is much less than the total liver inosine production of 212 mumol/h. These findings suggest that the liver is an organ site elaborating inosine, and that maintenance of a 3 mumol/l inosine in plasma is sufficient to meet the energy requirements of the pig red cells.


Assuntos
Metabolismo Energético , Eritrócitos/metabolismo , Inosina/metabolismo , Fígado/metabolismo , Porco Miniatura/metabolismo , Trifosfato de Adenosina/sangue , Envelhecimento , Animais , Glicólise , Hipoxantina , Hipoxantinas/sangue , Hipoxantinas/metabolismo , Inosina/sangue , Suínos , Ácido Úrico/metabolismo
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