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1.
Indoor Air ; 22(2): 148-58, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21913995

RESUMO

UNLABELLED: Outdoor particulate matter (PM(10)) is associated with detrimental health effects. However, individual PM(10) exposure occurs mostly indoors. We therefore compared the toxic effects of classroom, outdoor, and residential PM(10). Indoor and outdoor PM(10) was collected from six schools in Munich during teaching hours and in six homes. Particles were analyzed by scanning electron microscopy and X-ray spectroscopy (EDX). Toxicity was evaluated in human primary keratinocytes, lung epithelial cells and after metabolic activation by several human cytochromes P450. We found that PM(10) concentrations during teaching hours were 5.6-times higher than outdoors (117 ± 48 µg/m(3) vs. 21 ± 15 µg/m(3), P < 0.001). Compared to outdoors, indoor PM contained more silicate (36% of particle number), organic (29%, probably originating from human skin), and Ca-carbonate particles (12%, probably originating from paper). Outdoor PM contained more Ca-sulfate particles (38%). Indoor PM at 6 µg/cm(2) (10 µg/ml) caused toxicity in keratinocytes and in cells expressing CYP2B6 and CYP3A4. Toxicity by CYP2B6 was abolished with the reactive oxygen species scavenger N-acetylcysteine. We concluded that outdoor PM(10) and indoor PM(10) from homes were devoid of toxicity. Indoor PM(10) was elevated, chemically different and toxicologically more active than outdoor PM(10). Whether the effects translate into a significant health risk needs to be determined. Until then, we suggest better ventilation as a sensible option. PRACTICAL IMPLICATIONS: Indoor air PM(10) on an equal weight base is toxicologically more active than outdoor PM(10). In addition, indoor PM(10) concentrations are about six times higher than outdoor air. Thus, ventilation of classrooms with outdoor air will improve air quality and is likely to provide a health benefit. It is also easier than cleaning PM(10) from indoor air, which has proven to be tedious.


Assuntos
Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Material Particulado/análise , Material Particulado/toxicidade , Hidrocarboneto de Aril Hidroxilases/metabolismo , Biotransformação , Carbonato de Cálcio/análise , Carbonato de Cálcio/toxicidade , Linhagem Celular , Células Cultivadas , Criança , Citocromo P-450 CYP2B6 , Citocromo P-450 CYP3A/metabolismo , Alemanha , Habitação , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Microscopia Eletrônica de Varredura , Oxirredutases N-Desmetilantes/metabolismo , Tamanho da Partícula , Instituições Acadêmicas , Silício/análise , Silício/toxicidade , Enxofre/análise , Enxofre/toxicidade
2.
Leukemia ; 26(4): 788-94, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22033489

RESUMO

Despite being highly effective for newly diagnosed chronic myeloid leukemia (CML), imatinib not only is inactive against quiescent CML stem cells, but also has limited activity against blast crisis (BC) CML. The relative activity of Bcr-Abl and the expression levels of antiapoptotic proteins in proliferating and quiescent CD34(+) BC CML progenitor cells and the effects of targeting antiapoptotic proteins in these cells are unknown. Here we report higher levels of p-CrkL in quiescent than in proliferating CD34(+) progenitor cells and comparable expression levels of Bcl-2, Bcl-xL, Mcl-1 and XIAP in the two populations in BC CML. Inhibition of Bcl-2/Bcl-xL by ABT-737 in cells from patients with tyrosine kinase inhibitor (TKI)-resistant BC CML promoted apoptosis in quiescent CD34(+) progenitor cells with an efficacy similar to that in proliferating cells. Combination of ABT-737 with imatinib (which decreases Mcl-1 levels) or triptolide (which decreases Mcl-1 and XIAP) synergistically induced death of both proliferating and quiescent CD34(+) progenitor cells obtained from TKI-resistant BC CML patients. These results suggest that antiapoptotic proteins are critical targets in BC CML and that activation of apoptosis signaling can eliminate both proliferating and quiescent CD34(+) progenitor cells in BC CML, independent of response to TKIs.


Assuntos
Antígenos CD34/análise , Apoptose/efeitos dos fármacos , Crise Blástica/patologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Transdução de Sinais/fisiologia , Benzamidas , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Diterpenos/farmacologia , Compostos de Epóxi/farmacologia , Proteínas de Fusão bcr-abl/fisiologia , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Nitrofenóis/farmacologia , Fenantrenos/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirimidinas/farmacologia , RNA Mensageiro/análise , Sulfonamidas/farmacologia
3.
Clin Exp Allergy ; 41(8): 1116-24, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21518042

RESUMO

BACKGROUND: There is minimal data available concerning the dose-response relationship between allergen exposure and clinical reactivity for outdoor aeroallergens, such as timothy grass pollen. Timothy pollen-specific IgE (sIgE) determinations might assist in predicting the clinical reactivity in patients with allergic rhinoconjunctivitis (ARC). METHODS: Allergen-sIgE antibody levels of timothy grass pollen were correlated with individual threshold doses eliciting allergic reactions in skin prick test (SPT), conjunctival (CPT) and nasal (NPT) provocation tests in patients suffering from pollen-induced rhinoconjunctivitis and healthy controls. RESULTS: One hundred and four patients with ARC (median age: 27 years; range: 18-64; females: 58%) and 36 controls (25 years (22-77); females: 70%) were included in the study. Ninety-six percent of the patients showed a positive reaction in the nasal and 57% showed a positive reaction in the conjunctival provocation. With regarding to titrated SPT, 98% of the patients showed a positive skin test reaction; correlating with the level of sIgE for timothy (P < 0.001). For both provocation protocols, there was no correlation between the provocation concentration at the reaction and the level of sIgE for timothy. The ratio of sIgE/total IgE correlated with the dilution level of SPT (P < 0.002) and CPT (P < 0.01), respectively. CONCLUSION AND CLINICAL RELEVANCE: A dose-response relationship between the levels of sIgE and clinical outcome of timothy allergen exposure could not be established. Although IgE-determination remains an important key element in allergy diagnosis, provocation tests are procedures of choice if the clinical relevance of an allergen has to be confirmed.


Assuntos
Alérgenos/imunologia , Imunoglobulina E/análise , Testes Imunológicos/métodos , Phleum/imunologia , Pólen/imunologia , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/imunologia , Adolescente , Adulto , Alérgenos/efeitos adversos , Reações Antígeno-Anticorpo , Feminino , Humanos , Imunoglobulina E/imunologia , Masculino , Pessoa de Meia-Idade , Testes de Provocação Nasal , Pólen/efeitos adversos , Estudos Prospectivos , Testes Cutâneos , Adulto Jovem
4.
Allergy ; 65(7): 850-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20132158

RESUMO

BACKGROUND: Proof is lacking that pollen count is representative for allergen exposure, also because allergens were found in nonpollen-bearing fractions of ambient air. OBJECTIVE: We monitored simultaneously birch pollen and the major birch pollen allergen Bet v 1 in different size fractions of ambient air from 2004 till 2007 in Munich, Germany. METHODS: Air was sampled with a ChemVol high-volume cascade impactor equipped with stages for particulate matter (PM)>10 microm, 10 microm>PM>2.5 microm, and 2.5 microm>PM>0.12 microm. Allergen was determined with a Bet v 1-specific ELISA. Pollen count was assessed with a Burkard pollen trap. We also measured the development of allergen in pollen during ripening. RESULTS: About 93 +/- 3% of Bet v 1 was found in the PM > 10 microm fraction, the fraction containing birch pollen. We did not measure any Bet v 1 in 2.5 microm > PM > 0.12 microm. Either in Munich no allergen was in this fraction or the allergen was absorbed to diesel soot particles that also deposit in this fraction. Pollen released 115% more Bet v 1 in 2007 than in 2004. Also within 1 year, the release of allergen from the same amount of pollen varied more than 10-fold between different days. This difference was explained by a rapidly increasing expression of Bet v 1 in pollen in the week just before pollination. Depending on the day the pollen is released during ripening, its potency varies. CONCLUSION: In general, pollen count and allergen in ambient air follow the same temporal trends. However, because a 10-fold difference can exist in allergen potency of birch pollen, symptoms might be difficult to correlate with pollen counts, but perhaps better with allergen exposure.


Assuntos
Ar/análise , Antígenos de Plantas/análise , Betula , Monitoramento Ambiental/métodos , Pólen , Antígenos de Plantas/imunologia , Betula/imunologia , Ensaio de Imunoadsorção Enzimática , Alemanha , Pólen/imunologia , Rinite Alérgica Sazonal/imunologia
5.
Allergy ; 65(7): 903-10, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20002660

RESUMO

BACKGROUND: Itch is a major symptom of allergic skin disease. Acupuncture has been shown to exhibit a significant effect on histamine-induced itch in healthy volunteers. We investigated the effect of acupuncture on type I hypersensitivity itch and skin reaction in a double-blind, randomized, placebo-controlled, crossover trial. METHODS: An allergen stimulus (house dust mite or grass pollen skin prick) was applied to 30 patients with atopic eczema before (direct effect) and after (preventive effect) two experimental approaches or control observation: acupuncture at points Quchi and Xuehai [verum acupuncture (VA), dominant side], 'placebo-point' acupuncture (PA, dominant side), no acupuncture (NA). Itch intensity was recorded on a visual analogue scale. After 10 min, wheal and flare size and skin perfusion (via LASER-Doppler) were measured at the stimulus site, and the validated Eppendorf Itch Questionnaire (EIQ) was answered. RESULTS: Mean itch intensity was significantly lower in VA (35.7 +/- 6.4) compared to NA (45.9 +/- 7.8) and PA (40.4 +/- 5.8) regarding the direct effect; and significantly lower in VA (34.3 +/- 7.1) and PA (37.8 +/- 5.6) compared to NA (44.6 +/- 6.2) regarding the preventive effect. In the preventive approach, mean wheal and flare size were significantly smaller in VA (0.38 +/- 0.12 cm(2)/8.1 +/- 2.0 cm(2)) compared to PA (0.54 +/- 0.13 cm(2)/13.5 +/- 2.8 cm(2)) and NA (0.73 +/- 0.28 cm(2)/15.1 +/- 4.1 cm(2)), and mean perfusion in VA (72.4 +/- 10.7) compared to NA (84.1 +/- 10.7). Mean EIQ ratings were significantly lower in VA compared to NA and PA in the treatment approach; and significantly lower in VA and PA compared to NA in the preventive approach. CONCLUSIONS: Acupuncture at the correct points showed a significant reduction in type I hypersensitivity itch in patients with atopic eczema. With time the preventive point-specific effect diminished with regard to subjective itch sensation, whereas it increased in suppressing skin-prick reactions.


Assuntos
Terapia por Acupuntura , Dermatite Atópica/terapia , Hipersensibilidade Imediata/terapia , Prurido/prevenção & controle , Adulto , Alérgenos/imunologia , Animais , Estudos Cross-Over , Dermatite Atópica/complicações , Método Duplo-Cego , Feminino , Humanos , Hipersensibilidade Imediata/complicações , Fluxometria por Laser-Doppler , Masculino , Placebos , Poaceae/imunologia , Pólen/imunologia , Prurido/etiologia , Pyroglyphidae/imunologia , Fluxo Sanguíneo Regional , Pele/irrigação sanguínea , Pele/imunologia , Testes Cutâneos
6.
Leukemia ; 23(10): 1755-62, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19458629

RESUMO

Kinesin spindle protein (KSP), a microtubule-associated motor protein essential for cell cycle progression, is overexpressed in many cancers and is a potential anti-tumor target. We found that inhibition of KSP by a selective inhibitor, ARRY-520, blocked cell cycle progression, leading to apoptosis in acute myeloid leukemia cell lines that express high levels of KSP. Knockdown of p53, overexpression of XIAP and mutation in caspase-8 did not significantly affect sensitivity to ARRY-520, suggesting that the response is independent of p53, XIAP and the extrinsic apoptotic pathway. Although ARRY-520 induced mitotic arrest in both HL-60 and Bcl-2-overexpressing HL-60Bcl-2 cells, cell death was blunted in HL-60Bcl-2 cells, suggesting that the apoptotic program is executed through the mitochondrial pathway. Accordingly, inhibition of Bcl-2 by ABT-737 was synergistic with ARRY-520 in HL-60Bcl-2 cells. Furthermore, ARRY-520 increased Bim protein levels prior to caspase activation in HL-60 cells. ARRY-520 significantly inhibited tumor growth of xenografts in SCID mice and inhibited AML blast but not normal colony formation, supporting a critical role for KSP in proliferation of leukemic progenitor cells. These results demonstrate that ARRY-520 potently induces cell cycle block and subsequent death in leukemic cells via the mitochondrial pathway and has the potential to eradicate AML progenitor cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Cinesinas/antagonistas & inibidores , Mitocôndrias/efeitos dos fármacos , Tiadiazóis/farmacologia , Animais , Western Blotting , Caspase 8/genética , Caspase 8/metabolismo , Linhagem Celular Tumoral , Ensaio de Unidades Formadoras de Colônias , Feminino , Humanos , Cinesinas/metabolismo , Camundongos , Camundongos SCID , Mitocôndrias/metabolismo , Mutação/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Allergy ; 63(11): 1418-27, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18925878

RESUMO

Gender differences in the development and prevalence of human diseases have long been recognized. Immense interest grows in the understanding of the role of sex hormones in the homeostasis of immunity. Asthma predominates in boys before puberty and this gender preference reverses after puberty and in adulthood, when adult women tend to have a more severe disease, often recalcitrant to treatment. Atopic eczema in preschool children shows insignificant gender difference or male preponderance in different studies, with more adult females suffering from atopic eczema. The limited data on the prevalence of immediate hypersensitivity to hymenoptera venom show controversial results. Discrepancy exists regarding the gender difference in food allergy, with females reporting significantly more allergic reactions in questionnaire studies. In general, adverse reactions to nonionic iodinated radiocontrast media are more commonly observed in females. The course of allergic diseases varies unpredictably during pregnancy, whereas hormone replacement therapy in postmenopausal women usually has a favorable influence on the course of asthma. Experiments in rodents confirm an effect of estrogens on mast cell activation and allergic sensitization, while progesterone is shown to suppress histamine release but potentiate IgE induction. Dehydroepiandrosterone may antagonize the production of Th2 cytokines but the effect of testosterone and the other androgens remains less defined. Actual data from human studies are lacking.


Assuntos
Hormônios Esteroides Gonadais/imunologia , Hipersensibilidade/imunologia , Caracteres Sexuais , Anafilaxia/imunologia , Anafilaxia/metabolismo , Angioedema/imunologia , Angioedema/metabolismo , Animais , Asma/imunologia , Asma/metabolismo , Conjuntivite Alérgica/imunologia , Conjuntivite Alérgica/metabolismo , Anticoncepcionais Orais/imunologia , Anticoncepcionais Orais/metabolismo , Dermatite Atópica/imunologia , Dermatite Atópica/metabolismo , Feminino , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Humanos , Hipersensibilidade/metabolismo , Masculino , Menopausa/imunologia , Menopausa/metabolismo , Menstruação/imunologia , Menstruação/metabolismo , Urticária/imunologia , Urticária/metabolismo
8.
HNO ; 56(8): 752-8, 2008 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-18648759

RESUMO

The increase in allergic diseases is inter alia explained by the adjuvant effect of environmental pollutants: (1) The interaction between traffic-related airborne particles and pollen grains in the atmosphere may lead to agglomeration of particles on the surface of allergen carriers inducing their activation and to modulation of allergen release, generation of allergenic aerosols and adsorption of pollen proteins to airborne particles. (2) Anthropogenic air pollutants enhance the release of pollen-associated lipid mediators (PALMs) from pollen grains, substances with proinflammatory and immune modulating effects, which can lead to enhancement of allergic symptoms and maintenance of disease. (3) Air pollutants, such as NO(2), ozone, secondhand tobacco smoke, fine and ultrafine particles play an important role as adjuvants and trigger factors for allergic disease development as well as for elicitation and aggravation of allergic symptoms. (4) Polymorphisms in phase II drug-metabolizing enzymes can modulate susceptibility to the adjuvant effects of anthropogenic air pollutants on the IgE-mediated immune response. This highlights gene-environment interactions, which play an important role in the manifestation of allergic diseases.


Assuntos
Meio Ambiente , Poluentes Ambientais , Hipersensibilidade/etiologia , Hipersensibilidade/fisiopatologia , Otorrinolaringopatias/etiologia , Otorrinolaringopatias/fisiopatologia , Humanos , Hipersensibilidade/epidemiologia , Otorrinolaringopatias/epidemiologia
12.
Leukemia ; 19(11): 1977-84, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16151469

RESUMO

Anaplastic large-cell lymphoma (ALCL) is a heterogeneous lymphoma category in which a subset of cases carry the t(2;5)(p23;q35) or variant translocations resulting in overexpression of anaplastic lymphoma kinase (ALK). LY293111 (2-[2-propyl-3-[3-[2-ethyl-4-(4-fluorophenyl)-5-hydroxyphenoxy]-propoxy]-phenoxy] benzoic acid sodium salt) is a leukotriene B4 receptor antagonist, which was found to be safe and tolerable in Phase I clinical trials. In this study, we investigated the potential therapeutic effects and mechanisms of action of LY293111 in ALCL cell lines. LY293111 inhibited proliferation of both ALK(+) and ALK(-) ALCL cell in a dose-dependent fashion and induced complete G(1)-S cell cycle arrest, which was accompanied by upregulation of p27 and downregulation of cyclin E. Pretreatment with LY293111 for 4 h resulted in profound inhibition of serum-induced phosphorylation of extracellular-regulated kinases-1 and 2 and Akt and a concomitant increase in the phosphorylation of the stress-activated kinase c-jun N-terminal kinases (JNK). Simultaneously, LY293111 induced caspase-dependent apoptosis via activation of the intrinsic pathway, including early loss of mitochondrial inner transmembrane potential and the production of reactive oxygen species (ROS), cleavage of caspases-9, -3, poly ADP-ribose polymerase (PARP) and X-linked inhibitor of apoptosis. The phospho-JNK inhibitor SP600125 partially protected Sup-M2 cells from LY293111-induced apoptosis, PARP cleavage and ROS generation, suggesting a role for JNK in LY293111-induced cell death. These results warrant further studies of LY293111 in ALCL.


Assuntos
Apoptose/efeitos dos fármacos , Benzoatos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/patologia , Proteínas de Ciclo Celular/biossíntese , Ciclina E/biossíntese , Inibidor de Quinase Dependente de Ciclina p27 , Relação Dose-Resposta a Droga , Regulação para Baixo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , MAP Quinase Quinase 4 , Potenciais da Membrana , Mitocôndrias/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação , Espécies Reativas de Oxigênio , Receptores do Leucotrieno B4 , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor/biossíntese , Regulação para Cima
13.
Rofo ; 176(12): 1770-5, 2004 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-15573288

RESUMO

PURPOSE: To evaluate the diagnostic accuracy of direct multidetector CT arthrography (CTA) and direct MR arthrography (MRA) in patients suffering from chronic shoulder instability. MATERIALS AND METHODS: Twenty-nine patients suffering from chronic shoulder instability were included into a prospective study. In all cases, the indication for direct CTA and arthroscopy was set by the orthopedic surgeon. Prior to the imaging procedures, 10 to 20 ml of a special combination of contrast media (including saline, Isovist(R) and Magnevist(R) in a relation of 125 : 125 : 1) was injected into the joint under sterile conditions. First, CTA was performed with a multidetector CT, with images reconstructed in the axial, semi-coronal and semi-sagittal planes. Thereafter, MRA was performed. Axial images were obtained using a T1-weighted, fat-saturated spin echo sequence and semi-coronal images using a T1-weighted FLASH-3D GRE sequence. The results of CTA and MTA were compared with results obtained from arthroscopy or arthrotomy. RESULTS: MRA was superior to CTA in the detection of labral lesions. The sensitivity of MRA was 96 % and the specificity 96 %, compared to a sensitivity of 76 % (p < 0.05) and specificity of 92 % for CTA. Both methods showed the same effectiveness concerning the assessment of capsule distension (sensitivity for both techniques: 91 %). CONCLUSIONS: MRA seems to be superior to CTA in the diagnostic workup of chronic shoulder instability even when using a multidetector CT technique.


Assuntos
Artrografia/métodos , Instabilidade Articular/diagnóstico , Imageamento por Ressonância Magnética/métodos , Articulação do Ombro , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Doença Crônica , Meios de Contraste , Feminino , Humanos , Instabilidade Articular/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Escápula/diagnóstico por imagem , Escápula/patologia , Sensibilidade e Especificidade , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/patologia
14.
Eur J Pediatr Surg ; 14(4): 279-82, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15343470

RESUMO

A 12-year-old boy with Lennox syndrome presented with an acute abdomen and a history of progressive abdominal pain and vomiting over 3 weeks. The uncommon finding in this case was a foreign body detected in a lower loop of the jejunum causing radiological and clinical signs of jejunitis/ileitis. The foreign body had to be removed surgically and turned out to be a hard (originally soft) plastic part of a towel rack.


Assuntos
Corpos Estranhos/complicações , Ileíte/etiologia , Obstrução Intestinal/etiologia , Dor Abdominal/etiologia , Criança , Humanos , Ileíte/cirurgia , Obstrução Intestinal/cirurgia , Jejuno/diagnóstico por imagem , Jejuno/patologia , Jejuno/cirurgia , Masculino , Radiografia , Resultado do Tratamento , Vômito/etiologia
15.
Rofo ; 176(10): 1485-92, 2004 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-15383983

RESUMO

PURPOSE: To evaluate the effect of dexamethasone on the growth of cultured human aortic smooth muscle cells in an in-vitro model depending on the dose applied. MATERIALS AND METHODS: Commercially available human aortic smooth muscle cells (haSMC) were incubated with different doses of dexamethasone (10(-6), 10(-8), 10(-10) mol/l). For 20 days, the dose-depending effects of dexamethasone on cell growth were studied by analyzing cell proliferation, clonogenic activity as well as cell cycle distribution. In addition, the migratory ability of haSMC was evaluated using a two compartment in-vitro model. RESULTS: Cell growth was reduced in a dose dependent manner. An applied dose of 10(-6) M dexamethasone effectively inhibited cell growth for the follow-up period of 20 days. Cell cycle analysis revealed a G1-phase block which was dose dependent and significant for a dose of 10(-6) M. Also a reduction of haSMC clonogenic activity could be found in the colony formation assays. Finally, dexamethasone reduced the migratory ability of the treated cells significantly for doses of 10(-6) and 10(-8) M. CONCLUSION: Depending on the dose applied, incubation with dexamethasone results in a significant growth reduction of cultured haSMC, which may be due to a drug induced G1-phase block. Dexamethasone also reduces the clonogenic activity as well as the migratory ability of cultured haSMC.


Assuntos
Angioplastia com Balão , Anti-Inflamatórios/farmacologia , Aorta/efeitos dos fármacos , Constrição Patológica/prevenção & controle , Dexametasona/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Stents , Anti-Inflamatórios/administração & dosagem , Aorta/citologia , Arteriosclerose/prevenção & controle , Ciclo Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Meios de Cultura , Dexametasona/administração & dosagem , Seguimentos , Oclusão de Enxerto Vascular , Humanos , Hiperplasia , Recidiva , Fatores de Tempo , Túnica Íntima/patologia
17.
Arch Orthop Trauma Surg ; 123(8): 436-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14574605

RESUMO

We report the case of a 45-year-old woman with spondylodiscitis at L1/L2, communicating with paravertebral, intravertebral and bilateral psoas abscesses. Percutaneous computed tomography (CT)-guided abscess drainage and an intravenous antibiotic therapy with Imipenem were performed. After removing the drainage at 2 weeks, the patient was discharged at 4 weeks with normalized blood parameters, normal temperature, and without need for analgesics. The underlying bacterium in the case was a very rare gram-negative anaerobic bacterium: Prevotella intermedia.


Assuntos
Infecções por Bacteroidaceae/diagnóstico , Discite/microbiologia , Vértebras Lombares/microbiologia , Prevotella intermedia , Abscesso/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
18.
Leukemia ; 17(11): 2081-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12970762

RESUMO

XIAP is a member of the inhibitors-of-apoptosis family of proteins, which inhibit caspases and block cell death, with prognostic importance in AML. Here we demonstrate that cytokines regulate the expression of XIAP in leukemic cell lines and primary AML blasts. Inhibition of phosphatidylinositol-3 kinase (PI3K) with LY294002 and of the mitogen-activated protein kinase (MAPK) cascade by PD98059 resulted in decreased XIAP levels (34+/-8.7 and 23+/-5.7%, respectively). We then generated OCI-AML3 cells with constitutively phosphorylated Akt (p473-Akt) by retroviral gene transfer. Neither these nor Akt inhibitor-treated OCI-AML3 cells showed changes in XIAP levels, suggesting that XIAP expression is regulated by PI3K downstream effectors other than Akt. The induction of XIAP expression by cytokines through PI3K/MAPK pathways is consistent with its role in cell survival. Exposure of leukemic cells to chemotherapeutic agents decreased XIAP protein levels by caspase-dependent XIAP cleavage. Targeting XIAP by XIAP antisense oligonucleotide resulted in downregulation of XIAP, activation of caspases and cell death, and sensitized HL-60 cells to Ara-C. Our results suggest that XIAP is regulated by cytokines through PI3K, and to a lesser degree through MAPK pathways. Selective downregulation of XIAP expression might be of therapeutic benefit to leukemic patients.


Assuntos
Leucemia Mieloide Aguda/patologia , Proteínas/genética , Sequência de Bases , Crise Blástica/patologia , Sobrevivência Celular , Citocinas/farmacologia , Primers do DNA , Inibidores Enzimáticos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/fisiologia , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X , Dedos de Zinco
19.
Int J Radiat Oncol Biol Phys ; 49(3): 809-15, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11172964

RESUMO

PURPOSE: To evaluate dose-dependent growth-modulating effects of the beta-gamma emitter Rhenium-188 on cultured human aortic smooth muscle cells (haSMC). METHODS AND MATERIALS: HaSMC were plated in 25 cm(2) flasks. Two days after plating, cells were incubated with the Re-188 (beta E(max) 2.12 MeV, tissue range(max) < 10 mm, T(1/2) 17 h) for five days. The doses administered were 0.2 Gy, 1, 4, 6, 8, 16, and 32 Gy. After five days, the radionuclide was removed. Cell growth, cell cycle distribution, and clonogenic activity were analyzed for the following 25 days. RESULTS: The 0.2 and 1 Gy groups did not show relevant growth-inhibiting effects compared to the control groups. The 4 to 32 Gy groups presented dose-dependent growth inhibition, with a complete growth arrest of the 16 and 32 Gy groups. Clonogenic activity of the smooth muscle cell was strongly inhibited from doses > or =8 Gy. Flow cytometry showed a lasting dose-dependent G2/M phase block. CONCLUSION: Smooth muscle cell (SMC) growth can be controlled effectively with Re-188 for at least 25 days after radiation in vitro. As the first four weeks after arterial angioplasty are crucial concerning neointimal formation, Re-188 may be a valuable radionuclide to inhibit restenosis after arterial angioplasty.


Assuntos
Aorta/efeitos da radiação , Divisão Celular/efeitos da radiação , Músculo Liso Vascular/efeitos da radiação , Radioisótopos/farmacologia , Rênio/farmacologia , Aorta/citologia , Relação Dose-Resposta a Droga , Humanos , Interfase/efeitos da radiação , Músculo Liso Vascular/citologia , Radiobiologia
20.
Rofo ; 173(1): 72-6, 2001 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-11225421

RESUMO

PURPOSE: The aim of this study was to evaluate the capability of human aortic smooth musc e cells (HaSMC) and endothelial cells (EC) to recover after incubation with the combined beta/gamma emitter 186rhenium. MATERIALS AND METHODS: Two days after plating, HaSMC and EC were incubated for five days with 186Re (total doses applied 4 Gy-32 Gy). Cell counts were performed for a period of 30 days (haSMC) and 22 days (EC). To detect possible growth recovery, colony formation assays were plated for both cell types on day 5, 10, and 20 (and lay 30 for haSMC). RESULTS: Both cell types presented a dose-dependent growth inhibition which was maximum at a dose of 32 Gy. Human endothelial cells presented with total growth recovery at 4 and 8 Gy, and a partial growth recovery at 16 Gy. Smooth muscle cells only presented partial growth recovery at 4 and 8 Gy. At 16 Gy and more no recovery was detected. CONCLUSION: HaSMC as well as EC growth can be modulated effectively with 186Re over a period of 30 days in vitro. Compared to smooth muscle cells human endothelial cellls seem to possess a higher potential to recover at doses of 8 to 16 Gy. 186Re may be a valuable radionuclide to prevent restenosis.


Assuntos
Endotélio Vascular/citologia , Endotélio Vascular/efeitos da radiação , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos da radiação , Radioisótopos/farmacologia , Rênio/farmacologia , Angioplastia com Balão , Angioplastia Coronária com Balão , Aorta/citologia , Contagem de Células , Divisão Celular , Células Cultivadas , Humanos , Doses de Radiação , Recidiva , Fatores de Tempo
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