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1.
Pharmacol Res ; 140: 75-84, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30030171

RESUMO

Osteoporosis and bone fractures occur at higher frequency in patients with inflammatory bowel disease (IBD), and decreased bone mass is observed in animal models of colitis. Another consistent feature of colitis is increased serotonin (5-HT) availability in the intestinal mucosa. Since gut-derived 5-HT can decrease bone mass, via activation of 5-HT1B receptors on pre-osteoblasts, we tested the hypothesis that 5-HT contributes to bone loss in colitis. Colitis was chronically induced in mice by adding dextran sodium sulfate (DSS) to their drinking water for 21 days. At day 21, circulating 5-HT levels were elevated in DSS-inflamed mice. Micro-computed tomography of femurs showed a decrease in trabecular bone volume fraction, formation, and surface area, due largely to decreased trabecular numbers in DSS-treated mice. The colitis-induced loss of trabecular bone was significantly suppressed in mice treated with the 5-HT synthesis inhibitor, p-chloro-DL-phenylalanine (PCPA; 300 mg/kg/day IP daily), and in mice treated with the 5-HT1B receptor antagonist GR55562 (1 mg/Kg/day SC daily). The 5-HT reuptake transporter (SERT) is critical for moving 5-HT from the interstitial space into enterocytes and from serum into platelets. Mice lacking SERT exhibited significant deficits in trabecular bone mass that are similar to those observed in DSS-inflamed mice, and these deficits were not extensively worsened by DSS-induced colitis in the SERT-/- mice. Taken together, findings from both the DSS and SERT-/- mouse models support a contributing role for 5-HT as a significant factor in bone loss induced by colitis.


Assuntos
Reabsorção Óssea/metabolismo , Colite/metabolismo , Serotonina/metabolismo , Animais , Reabsorção Óssea/diagnóstico por imagem , Colite/induzido quimicamente , Colite/patologia , Sulfato de Dextrana , Fêmur/diagnóstico por imagem , Fêmur/patologia , Mucosa Intestinal/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Microtomografia por Raio-X
2.
Lymphology ; 49(1): 15-20, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29906059

RESUMO

Emberger syndrome, or primary lymphedema with myelodysplasia, is a severe rare disease characterized by early primary lymphedema and blood anomalies including acute childhood leukemia. The syndrome is associated with heterozygous mutations in the GATA2 gene. We report on a 13-year-old boy who developed lymphedema of the right lower limb at age 6 years which was accompanied by severe panleukopenia and repeated episodes of erysipelas. The suspicion of Emberger syndrome was confirmed by detection of a new germinal line GATA2 mutation c.414_417del, p.Ser139Cysfs*78. Clinical treatment included a bone marrow transplant from the father.This case is one of a very limited number of Emberger syndrome cases documented in the literature, and genetic testing proved fundamental for definition of the condition and its association with a de novo mutation in the GATA2 which is reported here for the first time.


Assuntos
Fator de Transcrição GATA2/genética , Leucopenia/genética , Linfedema/genética , Síndromes Mielodisplásicas/genética , Adolescente , Transplante de Medula Óssea , Erisipela/etiologia , Humanos , Leucopenia/complicações , Leucopenia/terapia , Linfangite/etiologia , Linfedema/complicações , Linfedema/diagnóstico por imagem , Linfografia , Linfocintigrafia , Imageamento por Ressonância Magnética , Masculino , Mutação , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/terapia , Síndrome
3.
Clin Genet ; 85(4): 376-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23586500

RESUMO

We describe a family with recurrent 11q23-qter deletion Jacobsen syndrome in two affected brothers, with unique mosaic deletion 'rescue' through development of uniparental disomy (UPD) in the mother and one of the brothers. Inheritance studies show that the deleted chromosome is of maternal origin in both boys, and microarray shows a break near the ASAM gene. Parental lymphocyte chromosomes were normal. However, the mother is homozygous in lymphocytes for all loci within the deleted region in her sons, and presumably has UPD for this region. In addition, she is mosaic for the 11q deletion seen in her sons at a level of 20-30% in skin fibroblasts. We hypothesize that one of her #11 chromosomes shows fragility, that breakage at 11q23 occurred with telomeric loss in some cells, but 'rescue' from the deletion occurred in most cells by the development of mitotic UPD. She apparently carries the 11q deletion in her germ line resulting in recurrence of the syndrome. The older son is mosaic for the 11q cell line (70-88%, remainder 46,XY), and segmental UPD11 'rescue' apparently also occurred in his cytogenetically normal cells. This is a novel phenomenon restoring disomy to an individual with a chromosomal deletion.


Assuntos
Cromossomos Humanos Par 11 , Síndrome da Deleção Distal 11q de Jacobsen/genética , Dissomia Uniparental , Deleção Cromossômica , Feminino , Humanos , Masculino , Mosaicismo , Linhagem
4.
Orthopade ; 43(11): 966-75, 2014 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-25300281

RESUMO

BACKGROUND: Bone geometry following osteotomy around the knee suggests that biplanar rather than uniplanar open wedge techniques simultaneously create smaller wedge volumes and larger bone surface areas. However, precise data on the bone surface area and wedge volume resulting from both open and closed wedge high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) techniques remain unknown. OBJECTIVES: It was hypothesized that biplanar rather than uniplanar osteotomy techniques better reflect the ideal geometrical requirements for bone healing, representing a large cancellous bone surface combined with a small wedge volume. METHODS: Tibial and femoral artificial bones were assigned to four different groups of valgisation and varisation osteotomy consisting of open wedge and closed wedge techniques in a uniplanar and biplanar fashion. Bone surface areas of all osteotomy planes were quantified. Wedge volumes were determined using a prism-based algorithm and applying standardized wedge heights of 5 mm, 10 mm and 15 mm. RESULTS: Both femoral and tibial biplanar osteotomy techniques created larger contact areas and smaller wedge volumes compared to the uniplanar open wedge techniques. CONCLUSION: Although this idealized geometrical view of bony geometry excludes all biological factors that might influence bone healing, the current data suggest a general rule for the standard osteotomy techniques applied and all surgical modifications: reducing the amount of slow gap healing and simultaneously increasing the area of faster contact healing may be beneficial for osteotomy healing. Thus, biplanar rather than uniplanar osteotomy should be performed for osteotomy around the knee.


Assuntos
Fêmur/anatomia & histologia , Fêmur/cirurgia , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/cirurgia , Osteotomia/métodos , Tíbia/anatomia & histologia , Tíbia/cirurgia , Humanos , Modelos Anatômicos , Tamanho do Órgão , Propriedades de Superfície
5.
Pulm Pharmacol Ther ; 25(1): 19-26, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22051450

RESUMO

BACKGROUND: Tiotropium has been associated with an increased risk of mortality and/or cardiovascular events. Recent data from RCTs suggests tiotropium Handihaler to be safe, but its safety has not yet been fully investigated under real-life circumstances. METHODS: We conducted 2 nested case-control studies in a COPD cohort from the Dutch IPCI database. In the first case-control study, cases had a cardiovascular or cerebrovascular endpoint (CCVE): stroke and transient ischemic attack (TIA), myocardial infarction, heart failure and/or ventricular arrhythmia. In the second, cases were all patients who died. Cases were matched to controls on age, sex and index date. Conditional logistic regression analysis was used to calculate adjusted odds ratios (OR(adj)) with 95% confidence intervals (CI) for tiotropium vs. long-acting beta-agonists (LABA). RESULTS: Within a cohort of 6788 COPD patients, 784 CCVE's and 1032 deaths were reported. Compared to current LABA use, use of tiotropium Handihaler was neither associated with an increased risk of a CCVE (OR(adj) 0.89, 95% 0.55-1.44) nor with an increased risk of death (OR(adj) 0.79, 95% CI 0.49-1.28). CONCLUSIONS: In real life, use of tiotropium Handihaler in COPD patients is not associated with an increased risk of a CCVE or mortality compared to LABA.


Assuntos
Broncodilatadores/efeitos adversos , Broncodilatadores/uso terapêutico , Doenças Cardiovasculares/induzido quimicamente , Transtornos Cerebrovasculares/induzido quimicamente , Nebulizadores e Vaporizadores , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Derivados da Escopolamina/efeitos adversos , Derivados da Escopolamina/uso terapêutico , Agonistas Adrenérgicos beta/efeitos adversos , Adulto , Fatores Etários , Idoso , Arritmias Cardíacas/induzido quimicamente , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/mortalidade , Broncodilatadores/administração & dosagem , Doenças Cardiovasculares/mortalidade , Estudos de Casos e Controles , Transtornos Cerebrovasculares/mortalidade , Estudos de Coortes , Intervalos de Confiança , Bases de Dados Factuais , Determinação de Ponto Final , Feminino , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/mortalidade , Humanos , Ataque Isquêmico Transitório/induzido quimicamente , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/mortalidade , Razão de Chances , Doença Pulmonar Obstrutiva Crônica/mortalidade , Derivados da Escopolamina/administração & dosagem , Fatores Sexuais , Acidente Vascular Cerebral/induzido quimicamente , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/mortalidade , Brometo de Tiotrópio
6.
Orthopade ; 40(1): 41-51, 2011 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-21207223

RESUMO

Recurrent anterior shoulder instability is a frequent and severe problem for patients. The Bankart operation with reconstruction of the labrum, capsule and ligament is the established treatment method, which is usually performed arthroscopically. However, the results of the Bankart operation deteriorate if there is significant bone loss at the glenoid or humerus and also when there is structural damage to the anteroinferior glenohumeral ligament and labrum. In 1954 Latarjet described the technique of coracoid transfer to the anterior glenoid. This procedure has become popular for the treatment of anterior shoulder instability especially in France and is performed in an open technique.In this paper we describe the indications, operative technique and early results of coracoid transfer in a completely arthroscopic technique.


Assuntos
Artroscopia/instrumentação , Artroscopia/métodos , Instabilidade Articular/cirurgia , Osso Escafoide/cirurgia , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos
7.
Opt Express ; 17(3): 1340-5, 2009 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-19188962

RESUMO

We present a high-repetition-rate, femtosecond optical parametric chirped pulse amplifier (OPCPA). Its seed signal is obtained by difference frequency generation from the two-branch output of a commercially available Er:fiber laser amplifier. The optical parametric amplifier is pumped by a commercially available diode-pumped solid-state laser. In a two-stage amplification setup we have achieved a gain of 100'000, resulting in approximately 1 microJ femtosecond mid-infrared pulses in the wavelength range between 3 and 4 microm and an amplification bandwidth of >300 nm at a repetition rate of 100 kHz. The pulses have been compressed to 92 fs by a 4-prism compressor.

8.
J Neurol Neurosurg Psychiatry ; 80(1): 13-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18931004

RESUMO

BACKGROUND: Cross-sectional reports suggest that statin users are less likely to have Alzheimer disease (AD). Prospective studies have provided inconsistent evidence. Moreover, it is unclear whether the association differs for lipophilic statins, those that could more easily pass the blood-brain barrier and hydrophilic statins. OBJECTIVES: To prospectively evaluate whether use of statins is associated with the risk of AD, and to determine whether associations differ for lipophilic and hydrophilic statins. METHOD: 6992 participants of the prospective, population-based Rotterdam Study were followed, from baseline (1990-1993) until January 2005 for incident AD. Data on all filled prescriptions came from pharmacy records. For each date on which each event occurred, cholesterol-lowering drug use for the person who experienced the event and all remaining persons in the cohort was categorised as "any" or "never" use. A distinction was made between statin, lipophilic and hydrophilic statins, and non-statin cholesterol-lowering drugs. Data were analysed with the Cox regression analysis, adjusting for sex, age and potential confounders. RESULTS: During follow-up (mean 9 years), 582 persons developed AD. Compared with never use of cholesterol-lowering drugs, statin use was associated with a decreased risk of AD (HR 0.57; 95% CI 0.37 to 0.90), but non-statin cholesterol-lowering drug use was not (HR 1.05; 95% CI 0.45 to 2.44). HRs were equal for lipophilic (HR 0.54; 95% CI 0.32 to 0.89) and hydrophilic statins (HR 0.54; 95% CI 0.26 to 1.11). CONCLUSION: In the general population, the use of statins, but not of non-statin cholesterol-lowering drugs, was associated with a lower risk of AD compared with never use of cholesterol-lowering drugs. The protective effect was independent of the lipophilicity of statins.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/epidemiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/epidemiologia , Lipídeos/sangue , Idoso , Doença de Alzheimer/sangue , Barreira Hematoencefálica/metabolismo , Feminino , Seguimentos , Humanos , Hiperlipidemias/sangue , Lipídeos/química , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Estudos Prospectivos , Fatores de Risco , Comportamento de Redução do Risco
9.
Methods Inf Med ; 48(1): 66-75, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19151886

RESUMO

OBJECTIVE: Health and medical informatics (HMI) is an evolving discipline. Therefore, evolving educational programs in HMI have to take a variety of requirements into account. The aim of this paper is to analyze these requirements and to compare them with the medical informatics program Heidelberg/Heilbronn, Germany. METHODS: Systematic analysis of the IMIA recommendations on educating HMI, the Bologna declaration, current technological and health care developments and the results of graduates surveys. RESULTS: The latest revision of the Heidelberg/Heilbronn medical informatics program not only takes current developments into account but also realizes the IMIA recommendations, the Bologna declaration and graduates' data and feedback obtained in structured surveys. The topics bioinformatics, IT security and telemedicine were strengthened, taking major research and application trends into account. The program has been transformed into a consecutive bachelor/master program. It qualifies its graduates to work in the field of medical informatics as well as in informatics. CONCLUSIONS: Medical informatics is a very broad field. Programs have to make concessions to scope: It is not possible to provide profound knowledge and skills in computer science and also teach a variety of application areas like bioinformatics, public health informatics and clinical informatics in depth within one medical informatics program. Many graduate programs in various nations concentrate on providing HMI skills to health care professionals.


Assuntos
Currículo , Educação de Pós-Graduação/métodos , Informática Médica/educação , Avaliação de Programas e Projetos de Saúde , Educação de Pós-Graduação/organização & administração , Escolaridade , Alemanha , Humanos , Modelos Educacionais , Desenvolvimento de Programas
10.
Neurogastroenterol Motil ; 30(9): e13349, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29644797

RESUMO

BACKGROUND: Multiple sclerosis (MS) is an autoimmune disease of the central nervous system that, in addition to motor, sensory, and cognitive symptoms, also causes constipation, which is poorly understood. Here, we characterize gastrointestinal (GI) dysmotility in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS and evaluate whether autoantibodies target the enteric nervous system (ENS) and cause dysmotility. METHODS: EAE was induced in male SJL and B6 mice. GI motility was assessed in vivo and ex vivo in wild type (WT) and B cell-deficient mice. MS and EAE serum was used to survey potential targets in the ENS and changes in the ENS structure were characterized using immunohistochemistry. KEY RESULTS: EAE mice developed accelerated gastric emptying and delayed whole GI transit with reduced colonic motility. Fecal water content was reduced, and colonic migrating myoelectrical complexes (CMMC) and slow waves were less frequent. Colons from EAE mice exhibited decreased GFAP levels in glia. Sera from MS patients and from EAE mice targeted ENS neurons and glia. B-cell deficiency in EAE protected against colonic dysmotility. CONCLUSIONS & INFERENCES: Consistent with symptoms experienced in MS, we demonstrate that EAE mice widely exhibit features of GI dysmotility that persisted in the absence of extrinsic innervation, suggesting direct involvement of ENS neurocircuitry. The absence of GI dysmotility in B cell-deficient mice with EAE together with EAE and MS serum immunoreactivity against ENS targets suggests that MS could be classified among other diseases known to induce autoimmune GI dysmotility.


Assuntos
Autoanticorpos/imunologia , Constipação Intestinal/imunologia , Encefalomielite Autoimune Experimental/complicações , Encefalomielite Autoimune Experimental/imunologia , Motilidade Gastrointestinal/imunologia , Animais , Sistema Nervoso Entérico/imunologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/complicações , Esclerose Múltipla/imunologia , Neuroglia/imunologia , Neurônios/imunologia
11.
Clin Pharmacol Ther ; 103(2): 341-348, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28543042

RESUMO

Myrcludex B acts as a hepatitis B and D virus entry inhibitor blocking the sodium taurocholate cotransporting polypeptide (SLC10A1). We investigated the effects of myrcludex B on plasma bile acid disposition, tenofovir pharmacokinetics, and perpetrator characteristics on cytochrome P450 (CYP) 3A. Twelve healthy volunteers received 300 mg tenofovir disoproxil fumarate orally and 10 mg subcutaneous myrcludex B. Myrcludex B increased total plasma bile acid exposure 19.2-fold without signs of cholestasis. The rise in conjugated bile acids was up to 124-fold (taurocholic acid). Coadministration of tenofovir with myrcludex B revealed no relevant changes in tenofovir pharmacokinetics. CYP3A activity slightly but significantly decreased by 29% during combination therapy. Myrcludex B caused an asymptomatic but distinct rise in plasma bile acid concentrations and had no relevant impact on tenofovir pharmacokinetics. Changes in CYP3A activity might be due to alterations in bile acid signaling. Long-term effects of elevated bile acids will require critical evaluation.


Assuntos
Antivirais/administração & dosagem , Ácidos e Sais Biliares/sangue , Lipopeptídeos/administração & dosagem , Inibidores da Transcriptase Reversa/farmacocinética , Tenofovir/farmacocinética , Administração Oral , Adulto , Antivirais/efeitos adversos , Antivirais/farmacocinética , Biomarcadores/sangue , Citocromo P-450 CYP3A/metabolismo , Interações Medicamentosas , Feminino , Humanos , Injeções Subcutâneas , Lipopeptídeos/efeitos adversos , Lipopeptídeos/farmacocinética , Masculino , Pessoa de Meia-Idade , Transportadores de Ânions Orgânicos Dependentes de Sódio/antagonistas & inibidores , Transportadores de Ânions Orgânicos Dependentes de Sódio/metabolismo , Estudos Prospectivos , Inibidores da Transcriptase Reversa/administração & dosagem , Inibidores da Transcriptase Reversa/efeitos adversos , Medição de Risco , Simportadores/antagonistas & inibidores , Simportadores/metabolismo , Tenofovir/administração & dosagem , Tenofovir/efeitos adversos , Regulação para Cima , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-17113274

RESUMO

During bone remodelling bone is resorbed by osteoclasts and replaced again by osteoblasts through the process of bone formation. Clinical trials and in vivo animal studies suggest that specific polyunsaturated fatty acids (PUFAs) might benefit bone health. As the number of functional osteoblasts is important for bone formation the effects of specific PUFAs on in vitro osteoblastic cell proliferation were investigated. Morphological studies were conducted to determine whether exposure of the cells to these agents caused structural damage to the cells thereby yielding invalid results. Results from this study showed that arachidonic acid (AA) and docosahexaenoic acid (DHA) both inhibit cell growth significantly at high concentrations. The anti-mitotic effect of AA is possibly independent of PGE(2) production, as PGE(2) per se had little effect on proliferation. Further study is required to determine whether reduced proliferation due to fatty acids could be due to increased differentiation of osteoblasts to the mature mineralising osteoblastic phenotype.


Assuntos
Ácido Araquidônico/farmacologia , Proliferação de Células/efeitos dos fármacos , Dinoprostona/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Animais , Células Cultivadas , Amarelo de Eosina-(YS) , Hematoxilina , Humanos , Camundongos
13.
Methods Inf Med ; 46(1): 67-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17224984

RESUMO

OBJECTIVES: In this paper we discuss solutions to the problem that medical teachers and students do not use modern computer-assisted instruction systems in medical education as much as expected by their developers. METHODS: As an example for a modern problem-based CAI system we introduce the CAMPUS shell system for case-based training in medicine. RESULTS: CAMPUS has received several awards and positive evaluation results. Nevertheless, the usage of such systems in courses and for self-study could be increased. CONCLUSIONS: Curricular integration of CAI as well as further improvements on existing CAI systems to increase the usage in medical education is essential.


Assuntos
Instrução por Computador , Sistemas de Apoio a Decisões Clínicas , Educação de Graduação em Medicina/métodos , Aprendizagem Baseada em Problemas , Faculdades de Medicina , Estudos de Casos e Controles , Simulação por Computador , Tecnologia Educacional , Docentes de Medicina , Retroalimentação , Alemanha , Humanos , Design de Software , Estudantes de Medicina
14.
Acta Chir Orthop Traumatol Cech ; 73(6): 400-2, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17266842

RESUMO

Conservative treatment of pathologic fractures of the long bones have been reported very infrequently, especially when fracture is caused by an tumour. This report highlights the possibility of an nonoperative treatment of a pathologic humerus fracture caused by an cartilaginous tumour with radiographic criterions of an chondrosarcoma.


Assuntos
Neoplasias Ósseas/complicações , Condrossarcoma/complicações , Consolidação da Fratura , Fraturas Espontâneas/etiologia , Fraturas do Úmero/etiologia , Úmero , Feminino , Fraturas Espontâneas/terapia , Humanos , Fraturas do Úmero/terapia , Pessoa de Meia-Idade
15.
Cancer Res ; 44(2): 784-90, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6692377

RESUMO

Cytogenetic studies of rat neurogenic tumor lines induced by ethylnitrosourea (ENU) have shown specific involvement of chromosome 4. The study reported here further characterizes the association of chromosome 4 abnormalities in rat tumor cell lines with regard to etiological agent, tissue of origin, and tumorigenic potential of cloned lines. Lines from rat gliomas induced by avian sarcoma virus did not show abnormalities of chromosome 4. ENU-induced rat tumors of nonneurogenic origin had numerical and/or structural abnormalities of chromosome 4 in seven of nine cell lines. In a comparison of two tumorigenic and two nontumorigenic cloned cell types from the same ENU-induced rat neural tumor, all showed excess chromosome 4. In addition, preneoplastic nervous system tissue, exposed to ENU in vivo, was cultured and sequentially monitored for the concurrent development of chromosome abnormalities and neoplastic properties. Abnormalities of chromosome 4 were observed in 3 of 14 tumorigenic lines and one nontumorigenic clone. The remaining lines had normal karyotypes or abnormalities involving chromosomes other than chromosome 4. Our results suggest that chromosome 4 abnormalities appear late in tumor development, are probably secondary to the tumorigenic potential of the studied cell lines, and apparently are not tissue specific. However, abnormalities of chromosome 4 may be associated preferentially with ENU oncogenesis.


Assuntos
Aberrações Cromossômicas/induzido quimicamente , Etilnitrosoureia , Neoplasias do Sistema Nervoso/genética , Compostos de Nitrosoureia , Animais , Linhagem Celular , Transformação Celular Viral , Transtornos Cromossômicos , Mapeamento Cromossômico , Cariotipagem , Neoplasias do Sistema Nervoso/induzido quimicamente , Ratos
16.
Cancer Res ; 52(21): 5926-32, 1992 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1327520

RESUMO

Different cell growth effects were observed in MCF-7 cells after six daily exposures to either 17 beta-estradiol (E2), 2-hydroxyestradiol (2-OHE2), or 2-methoxyestradiol (2-MeOE2) at 10 nM levels. 2-OHE2 enhanced cell growth significantly (P < 0.05) more than did the parent compound, whereas 2-MeOE2 inhibited cell growth. To identify the estrogen-affected cellular processes involved in cell cycle progression, hydroxy urea-synchronized MCF-7 cells were studied. No effects on DNA synthesis in mid-S-phase or on mitotic indices were observed after E2 or 2-OHE2 treatment. 2-MeOE2, however, significantly (P < 0.05) inhibited DNA synthesis and mitosis. Synchronized cells were exposed for 1 h to E2, 2-OHE2, or 2-MeOE2 before cAMP levels were determined in early S-phase and mid-S-phase, as well as during mitosis. E2 and 2-OHE2 had no effect, but 2-MeOE2 caused a significant (P < 0.05) increase in cAMP concentration in early S-phase and a decrease during mitosis. Phosphorylation of S-phase proteins was also studied. [32P]Pi incorporation was significantly (P < 0.05) enhanced in many proteins in 2-MeOE2-exposed cells. Small proteins (M(r) < 25,000), as well as large proteins (M(r) > 220,000), were most prominently affected. In comparison, E2 and 2-OHE2 had little effect. We suggest that the enhanced 2-MeOE2-induced protein phosphorylation during S-phase may affect S-phase events, which subsequently causes inhibition of mitosis. Protein synthesis during G2/M transition was unexpectedly enhanced by 2-OHE2 and was not enhanced by E2. [35S]Methionine incorporation into proteins in the order of M(r) 32,000-46,000, 47,000-50,000, 58,000-67,000, and 83,000-89,000 was significantly (P < 0.05) increased. 2-MeOE2 had no effect. The results of this study indicate that 2-OHE2 may be the more potent mitogen, whereas 2-MeOE2 acts as a cytostatin.


Assuntos
Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , DNA de Neoplasias/biossíntese , Estradiol/análogos & derivados , 2-Metoxiestradiol , Neoplasias da Mama/metabolismo , AMP Cíclico/metabolismo , Estradiol/farmacologia , Fase G2 , Humanos , Metionina/metabolismo , Mitose/efeitos dos fármacos , Peso Molecular , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Fase S , Fatores de Tempo , Células Tumorais Cultivadas
17.
Cancer Res ; 41(8): 2995-9, 1981 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7248955

RESUMO

Samplings of tumor cells from a patient with Stage IV neuroblastoma were analyzed for chromosome constitution. Chromosome preparations of the tumor cells from a bone marrow sample were compared to preparations of a solid metastatic tumor after growth in the nude mouse host or followed by culture. Six separate chromosome studies were done. The tumor karyotype demonstrated an overall stability, maintaining the consistent abnormalities of a 1p-, +17, and -22. Chromosomes 5 and 9 were also involved in structural abnormalities in sublines of the tumor cells. Double minutes were seen in all preparations.


Assuntos
Neuroblastoma/genética , Animais , Medula Óssea/patologia , Pré-Escolar , Humanos , Cariotipagem , Linfócitos/patologia , Masculino , Camundongos , Camundongos Nus , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Neuroblastoma/patologia , Pele/patologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-16198098

RESUMO

Polyunsaturated fatty acids (PUFAs) as well as oestrogen (E2) and parathyroid hormone (PTH) affect bone cells. The aim of the study was to determine whether arachidonic acid (AA), E2, and PTH increase prostaglandin E(2) (PGE(2)) synthesis in MG-63 and MC3T3-E1 osteoblastic cells and the level of mediation by COX-1 and COX-2. PGE(2) levels were determined in the conditioned culture media of MG-63 and MC3T3-E1 osteoblasts after exposure to AA, PTH and E2. Cells were pre-incubated in some experiments with the unselective COX inhibitor indomethacin or the COX-2 specific blocker NS-398. Indirect immunofluorescence was performed on MG-63 cells to detect the presence and location of the two enzymes involved. AA increased PGE(2) secretion in both cell lines; production by MC3T3-E1 cells, however, was significantly higher than that of MG-63 cells. This could be due to autoamplification via the EP(1) subtype of PGE receptors in mouse MC3T3-E1 osteoblasts. Both COX-1 and COX-2 affected the regulation of PGE(2) synthesis in MG-63 cells. E2 had no effect on PGE(2) secretion in both cell lines, while PTH caused a slight increase in PGE(2) synthesis in the MG-63 cell line.


Assuntos
Ácido Araquidônico/farmacologia , Dinoprostona/biossíntese , Estradiol/farmacologia , Osteoblastos/metabolismo , Hormônio Paratireóideo/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Humanos , Indometacina/farmacologia , Camundongos , Nitrobenzenos/farmacologia , Osteoblastos/efeitos dos fármacos , Osteossarcoma , Prostaglandina-Endoperóxido Sintases/metabolismo , Sulfonamidas/farmacologia
19.
Am J Med Genet ; 61(1): 65-7, 1996 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-8741921

RESUMO

Two brothers with presumed Baller-Gerold syndrome, one of whom was previously diagnosed with the association of vertebral, cardiac, renal, limb anomalies, anal atresia, tracheo-esophageal fistula (VACTERL) association with hydrocephalus, were evaluated for chromosome breakage because of severe thrombo cytopenia in one of them. Spontaneous and clastogen-induced breakage was markedly increased in both patients as compared to control individuals. Clinical manifestations and chromosome breakage, consistent with Fanconi anemia, in patients with a prior diagnosis of either Baller-Gerold syndrome, reported earlier in one other patient [Farrell et al., 1994: Am J Med Genet 50:98-99], or with VACTERL association with hydrocephalus, recently reported in 3 patients [Toriello et al., 1991: Proc Greenwood Genet Center 11:142; Porteus et al., 1992: Am J Med Genet 43:1032-1034], underline the clinical heterogeneity of Fanconi anemia and raise the question of whether these syndromes are distinct disorders or phenotypic variations of the same disease.


Assuntos
Anormalidades Múltiplas/genética , Craniossinostoses/genética , Anemia de Fanconi/genética , Hidrocefalia/genética , Rádio (Anatomia)/anormalidades , Anormalidades Múltiplas/diagnóstico , Pré-Escolar , Craniossinostoses/diagnóstico , Citogenética , Diagnóstico Diferencial , Anemia de Fanconi/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Núcleo Familiar , Síndrome
20.
Artigo em Inglês | MEDLINE | ID: mdl-12445489

RESUMO

Neuronal Ca-ATPase has the essential function of keeping intracellular Ca levels in the micromolar range. This is a prerequisite for normal neurotransmission. This study was designed to determine whether Ca-ATPase is a target for docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) action: results show that both these fatty acids are inhibitors of Ca-ATPase activity in synaptosomal membranes isolated from rat cerebral cortex (-65+/-5% at [DHA]=20 microg/ml, -59+/-7% at [EPA]=20 microg/ml). The inhibition caused by EPA, but not that of DHA, could be reversed completely by the addition of calphostin, a protein kinase C blocker. In contrast, DHA could stimulate Ca-ATPase activity (+132+/-5% at [DHA]=30 microg/ml) only in calmodulin-depleted membranes. In addition, Na,K-ATPase (which drives the Na-Ca exchanger) was inhibited by both DHA and EPA, both at 30 microg/ml (-15+/-0.7% and -42+/-1%, respectively). These results suggest a mechanism that explains the dampening effect of omega-3 fatty acids on neuronal activity.


Assuntos
ATPases Transportadoras de Cálcio/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Ácidos Graxos Ômega-3/farmacologia , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Relação Dose-Resposta a Droga , Masculino , Naftalenos/farmacologia , Ratos , Ratos Sprague-Dawley
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