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1.
Appetite ; 120: 654-665, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29061381

RESUMO

Previous research suggests that people's representations of alcoholic beverages play an important role in drinking behavior. However, relatively little is known about the contents of these representations. Here, we introduce the property generation task as a tool to explore these representations in detail. In a laboratory study (N = 110), and a bar field-study (N = 56), participants listed typical properties of alcoholic beverages, sugary beverages, and water. Each of these properties was then categorized using a previously developed, hierarchical coding scheme. For example, the property "sweet" was categorized as referring to "taste", which falls under "sensory experience", which falls under "consumption situation". Afterwards, participants completed measures of drinking behavior and alcohol craving. Results showed that alcoholic beverages were strongly represented in terms of consumption situations, with 57% and 69% of properties relating to consumption in the laboratory and the bar study, respectively. Specifically, alcoholic beverages were more strongly represented in terms of the social context of consumption (e.g., "with friends") than the other beverages. In addition, alcoholic beverages were strongly represented in terms of sensory experiences (e.g. "sweet") and positive outcomes (e.g. "creates fun"), as were the sugary beverages and water. In Study 1, the extent to which alcoholic beverages were represented in terms of social context was positively associated with craving and regularly consuming alcohol. The property generation task provides a useful tool to access people's idiosyncratic representations of alcoholic beverages. This may further our understanding of drinking behavior, and help to tailor research and interventions to reduce drinking of alcoholic and other high-calorie beverages.


Assuntos
Bebidas Alcoólicas , Bebidas , Meio Social , Adulto , Consumo de Bebidas Alcoólicas/prevenção & controle , Comportamento de Ingestão de Líquido , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Adulto Jovem
2.
Strahlenther Onkol ; 193(10): 823-830, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28695316

RESUMO

BACKGROUND: Definition of gross tumor volume (GTV) in hepatocellular carcinoma (HCC) requires dedicated imaging in multiple contrast medium phases. The aim of this study was to evaluate the interobserver agreement (IOA) in gross tumor delineation of HCC in a multicenter panel. METHODS: The analysis was performed within the "Stereotactic Radiotherapy" working group of the German Society for Radiation Oncology (DEGRO). The GTVs of three anonymized HCC cases were delineated by 16 physicians from nine centers using multiphasic CT scans. In the first case the tumor was well defined. The second patient had multifocal HCC (one conglomerate and one peripheral tumor) and was previously treated with transarterial chemoembolization (TACE). The peripheral lesion was adjacent to the previous TACE site. The last patient had an extensive HCC with a portal vein thrombosis (PVT) and an inhomogeneous liver parenchyma due to cirrhosis. The IOA was evaluated according to Landis and Koch. RESULTS: The IOA for the first case was excellent (kappa: 0.85); for the second case moderate (kappa: 0.48) for the peripheral tumor and substantial (kappa: 0.73) for the conglomerate. In the case of the peripheral tumor the inconsistency is most likely explained by the necrotic tumor cavity after TACE caudal to the viable tumor. In the last case the IOA was fair, with a kappa of 0.34, with significant heterogeneity concerning the borders of the tumor and the PVT. CONCLUSION: The IOA was very good among the cases were the tumor was well defined. In complex cases, where the tumor did not show the typical characteristics, or in cases with Lipiodol (Guerbet, Paris, France) deposits, IOA agreement was compromised.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Genes Immun ; 15(1): 25-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24173147

RESUMO

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is a costimulatory molecule that negatively regulates T-cell activation. Originally identified in murine CD8(+) T cells, it has been found to be rapidly induced on human T cells. Furthermore, CTLA-4 is expressed on regulatory T cells. Clinically, targeting CTLA-4 has clinical utility in the treatment of melanoma. Whether the expression of CTLA-4 is differentially regulated in CD8(+) vs CD4(+) human T cells is unclear. Here, we analyzed CTLA-4 in normal human CD4(+) and CD8(+) T-cell subsets and show for the first time that CTLA-4 is expressed significantly higher in the CD4(+) T cells than in CD8(+) T cells. CTLA-4 is higher at the protein and the transcriptional levels in CD4(+) T cells. This increase is due to the activation of the CTLA-4 promoter, which undergoes acetylation at the proximal promoter. Furthermore, we show that blocking CTLA-4 on CD4(+) T cells permits greater proliferation in CD4(+) vs CD8(+) cells. These findings demonstrate a differential regulation of CTLA-4 on CD4(+) and CD8(+) T-cell subsets, which is likely important to the clinical efficacy for anti-CTLA-4 therapies. The findings hint to strategies to modulate CTLA-4 expression by targeting epigenetic transcription to alter the immune response.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Antígeno CTLA-4/metabolismo , Fatores de Transcrição NFATC/metabolismo , Acetilação , Antígeno CTLA-4/genética , Proliferação de Células , Células Cultivadas , Regulação da Expressão Gênica , Histonas/metabolismo , Humanos , Ativação Linfocitária , Regiões Promotoras Genéticas , Linfócitos T Reguladores/metabolismo , Regulação para Cima
4.
Opt Express ; 21(14): 16431-43, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938494

RESUMO

In this study we present a new measurement technique to investigate the timescales of back side ablation of conductive films, using Molybdenum as an application example from photovoltaics. With ultrashort laser pulses at fluences below 0.6 J/cm(2), we ablate the Mo film in the shape of a fully intact Mo 'disc' from a transparent substrate. By monitoring the time-dependent current flow across a specifically developed test structure, we determine the time required for the lift-off of the disc. This value decreases with increasing laser fluence down to a minimum of 21 ± 2 ns. Furthermore, we record trajectories of the discs using a shadowgraphic setup. Ablated discs escape with a maximum velocity of 150 ± 5 m/s whereas droplets of Mo forming at the center of the disc can reach velocities up to 710 ± 11 m/s.


Assuntos
Condutometria/métodos , Lasers , Teste de Materiais/métodos , Membranas Artificiais , Molibdênio/química , Molibdênio/efeitos da radiação , Refratometria/métodos , Molibdênio/análise
5.
Dermatology ; 227(2): 171-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24080762

RESUMO

Radiodermatitis is a very common side effect in cancer treatment often leading to therapy delays and diminution of the patients' health state and quality of life. Despite a wide range of supportive strategies, radiodermatitis is still a major problem necessitating further improvements in prevention and treatment. Lactokine is a milk-based protein shown to assist in the reduction of skin redness. The treatment is a unique FDA-approved skin care system (R1 and R2). In this case presentation we describe the prophylactic use of R1 and R2 in a 63-year-old, female patient with a squamous cell carcinoma of the hypopharynx undergoing a platin-based chemoradiation. The application was feasible and safe and the patient developed only a slight radiodermatitis. To our knowledge this is the first report in the literature on the prophylactic use of R1 and R2. Further evidence will be provided by a prospective, clinical trial we have launched (CREAM-1; study registration in ISRCTN Registry: ISRCTN87302591). We also review the literature to give an overview about common strategies in the management of radiodermatitis.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Radiodermite/prevenção & controle , Higiene da Pele/instrumentação , Doença Aguda , Quimiorradioterapia/efeitos adversos , Aprovação de Equipamentos , Feminino , Humanos , Pessoa de Meia-Idade , Radiodermite/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço
6.
Growth Factors ; 30(5): 310-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22856597

RESUMO

Ligand-mediated activation of ErbB3 and ErbB4 is implicated in the pathogenesis of several human malignancies including cancer of the ovary and melanoma. We have used the broad ErbB ligand specificity of ErbB4 to assemble and express an ErbB4 fusion protein comprising the first 497 amino acids of the mature ErbB4 ectodomain fused to the human IgG Fc constant region. The purified fusion protein, designated sErbB4.497.Fc, binds the ErbB receptor ligands betacellulin and heregulin-ß1 (HRG-ß1) with high affinity (K(D) = 130 pM), an increase in affinity of 10- to 20-fold, respectively, compared with sErbB4.615.Fc. sErbB4.497.Fc inhibited ligand-stimulated phosphorylation of epidermal growth factor receptor and ErbB2, and blocked HRG-ß1 activation of the IKB/MAP/JNK/AKT signalling pathways. sErbB4.497.Fc inhibited HRG-ß1-stimulated proliferation in MCF7 cells. In a mouse tumour xenograft model, sErbB4.497.Fc as a monotherapy modestly inhibited the growth of MDA-MB-231 breast cancer cells. sErbB4.497.Fc may be useful in an adjuvant setting in combination with conventional therapeutic agents.


Assuntos
Receptores ErbB/metabolismo , Neuregulina-1/antagonistas & inibidores , Neuregulina-1/metabolismo , Receptores Fc/metabolismo , Animais , Betacelulina , Neoplasias da Mama/tratamento farmacológico , Células CHO , Linhagem Celular , Cricetinae , Receptores ErbB/genética , Receptores ErbB/uso terapêutico , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Células HEK293 , Humanos , Proteínas I-kappa B/antagonistas & inibidores , Proteínas I-kappa B/metabolismo , Imunoglobulina G/genética , Imunoglobulina G/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Células MCF-7 , Melanoma/patologia , Camundongos , Neoplasias Ovarianas/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor ErbB-4 , Receptores Fc/genética , Receptores Fc/uso terapêutico , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Phys Biol ; 8(5): 055008, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21832803

RESUMO

On top of the many external perturbations, cellular oscillators also face intrinsic perturbations due the randomness of chemical kinetics. Biomolecular oscillators, distinct in their parameter sets or distinct in their architecture, show different resilience with respect to such intrinsic perturbations. Assessing this resilience can be done by ensemble stochastic simulations. These are computationally costly and do not permit further insights into the mechanistic cause of the observed resilience. For reaction systems operating at a steady state, the linear noise approximation (LNA) can be used to determine the effect of molecular noise. Here we show that methods based on LNA fail for oscillatory systems and we propose an alternative ansatz. It yields an asymptotic expression for the phase diffusion coefficient of stochastic oscillators. Moreover, it allows us to single out the noise contribution of every reaction in an oscillatory system. We test the approach on the one-loop model of the Drosophila circadian clock. Our results are consistent with those obtained through stochastic simulations with a gain in computational efficiency of about three orders of magnitude.


Assuntos
Ritmo Circadiano/fisiologia , Animais , Drosophila/fisiologia , Modelos Biológicos , Processos Estocásticos
8.
Schweiz Arch Tierheilkd ; 153(11): 495-500, 2011 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22045453

RESUMO

Remission from diabetes is seen in 25 - 50 % of cats during the first months of therapy. The likelihood of remission is higher in old cats and cats with normal cholesterol than in young cats and cats with increased cholesterol. The results of an ongoing study indicate that initial intravenous insulin therapy has positive effects on remission rates and quality of metabolic control.


Assuntos
Doenças do Gato/terapia , Diabetes Mellitus/veterinária , Animais , Glicemia , Doenças do Gato/sangue , Doenças do Gato/patologia , Gatos , Colesterol/sangue , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/terapia , Insulina/administração & dosagem , Insulina/sangue , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Indução de Remissão , Fatores de Risco
9.
Int J Comput Assist Radiol Surg ; 16(6): 1043-1049, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34021859

RESUMO

PURPOSE: To show the feasibility of 3D-printed fixation masks for whole brain radiation therapy in a clinical setting and perform a first comparison to an established thermoplastic mask system. METHODS: Six patients were irradiated with whole brain radiotherapy using individually 3D-printed masks. Daily image guidance and position correction were performed prior to each irradiation fraction. The vectors of the daily position correction were compared to two collectives of patients, who were irradiated using the standard thermoplastic mask system (one cohort with head masks; one cohort with head and neck masks). RESULTS: The mean systematic errors in the experimental cohort ranged between 0.59 and 2.10 mm which is in a comparable range to the control groups (0.18 mm-0.68 mm and 0.34 mm-2.96 mm, respectively). The 3D-printed masks seem to be an alternative to the established thermoplastic mask systems. Nevertheless, further investigation will need to be performed. CONCLUSION: The prevailing study showed a reliable and reproducible interfractional positioning accuracy using individually 3D-printed masks for whole brain irradiation in a clinical routine. Further investigations, especially concerning smaller target volumes or other areas of the body, need to be performed before using the system on a larger basis.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Imobilização/métodos , Máscaras , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos
10.
Radiat Oncol ; 16(1): 23, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33522923

RESUMO

BACKGROUND: Radiation therapy and chemoradiation therapy play a major role in the definitive management of esophageal cancer. Survival in esophageal cancer patients is still relatively poor, mostly due to high rates of local recurrence and distant metastases. It is hypothesized that dose escalation in radiotherapy could improve outcomes. Therefore, this retrospective analysis aimed to investigate the outcomes and toxicity in patients treated with local dose escalation by means of using simultaneous integrated boost concepts. METHODS: Between 2012 and 2018, 101 patients with esophageal carcinoma were analyzed in this monocentric, retrospective study. All patients received definitive chemoradiation or radiation therapy alone as intensity modulated radiotherapy. The prescribed dose was 50.4 Gy in 28 fractions to the primary tumor and the elective lymph nodes as well as a simultaneous integrated boost (SIB) with 58.8 Gy to macroscopic tumor and lymph node metastases. Endpoints were overall survival (OS), progression free survival (PFS), local control rate (LCR) and toxicity. RESULTS: 60 patients (59.4%) received chemoradiation, 41 patients (40.6%) radiotherapy alone. The median follow up was 17 months (range 0-75 months). OS, PFS and LCR were at 63.9%, 53.9% and 59.9% after 1 year and 37.6%, 34.5% and 36.1%, respectively after 3 years. 16 patients (15.8%) in total developed a locoregional recurrence within the field of radiation. In 48 patients (47.5%) at least one grade III° (CTCAE) toxicity was documented during radiotherapy, mostly dysphagia (36 pat., 75%). One patient suffered from a grade IV° pneumonia. CONCLUSION: This retrospective analysis demonstrates that a SIB concept in definitive (chemo)radiation therapy is safe and feasible, showing acceptable outcomes in this patient cohort. Considering that this cohort mainly consists of elderly patients not eligible for chemotherapy in many cases, we emphasize the aspect of SIB radiation therapy as potential partial compensation for omitted simultaneous chemotherapy. Prospective studies are needed for validation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/mortalidade , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Recidiva Local de Neoplasia/terapia , Radioterapia de Intensidade Modulada/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
11.
J Vet Intern Med ; 24(6): 1314-21, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20840299

RESUMO

BACKGROUND: Clinical remission is frequent in cats with well-controlled diabetes mellitus, but few studies explored predictors of this phenomenon. HYPOTHESIS: Data retrieved from medical records at admission might be valuable to identify likelihood of remission and its duration in diabetic cats. ANIMALS: Ninety cats with newly diagnosed diabetes, followed-up until death or remission. METHODS: Retrospective cohort study. Data were collected from records at admission, including history, signalment, physical examination, haematology, and biochemical profile, and the occurrence and duration of remission, defined as normoglycemia without insulin for ≥4 weeks. Predictors of remission were studied with univariate and multivariate logistic regression. Factors associated with remission duration were analyzed with Kaplan-Meier and Cox proportional hazard models. RESULTS: Forty-five (50%) cats achieved remission, after a median time of 48 days (range: 8-216). By study end, median remission duration was 114 days (range: 30-3,370) in cats that died and 151 days (range: 28-1,180) in alive cats. Remission was more likely with higher age (OR: 1.23, 95% CI: 1.04-1.46; P=.01) and less likely with increased serum cholesterol (OR: 0.36, 95% CI: 0.11-0.87; P=.04). Remission was longer with higher body weight (HR: 0.65, 95% CI: 0.42-0.99; P=.04) and shorter with higher blood glucose (HR: 1.01, 95% CI: 1.00-1.02; P=.02). CONCLUSIONS AND CLINICAL IMPORTANCE: Age, body weight, cholesterol, and glucose levels are suggested for prediction of remission or its duration in diabetic cats. Older cats developing diabetes may have a better outcome, possibly suggesting a slower disease progression.


Assuntos
Doenças do Gato/patologia , Diabetes Mellitus/veterinária , Animais , Gatos , Estudos de Coortes , Diabetes Mellitus/patologia , Feminino , Masculino , Remissão Espontânea , Estudos Retrospectivos
12.
J Immunol Methods ; 341(1-2): 30-40, 2009 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-19038261

RESUMO

Vascular cell adhesion molecule 1 (VCAM-1) is involved in the recruitment of leukocytes to inflammatory sites. In this study we present the first functional knockdown of VCAM-1 using an ER retained antibody construct. We generated a knockdown construct encoding the VCAM-1 specific single chain variable fragment scFv6C7.1 fused to the C-terminal ER retention sequence KDEL. HEK-293:VCAM-YFP cells stably expressing a VCAM-YFP fusion protein were transiently transfected with the knockdown construct and showed down-regulation of surface VCAM-1. Knockdown efficiency of the system is time-dependent due to used transient transfection of the intrabody construct. Furthermore, intrabody mediated knockdown of HEK-293:VCAM-YFP cells also impaired cell-cell interaction with Jurkat cells that are endogenously expressing VLA-4, the physiological partner of VCAM-1. Posttranslational knockdown with ER retained antibodies seems to be a promising technique, as shown here for VCAM-1.


Assuntos
Anticorpos Monoclonais/farmacologia , Regulação para Baixo/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Região Variável de Imunoglobulina/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Animais , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Linhagem Celular , Regulação para Baixo/fisiologia , Retículo Endoplasmático/imunologia , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Camundongos , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/farmacologia , Molécula 1 de Adesão de Célula Vascular/imunologia
13.
Science ; 284(5421): 1845-8, 1999 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-10364559

RESUMO

The efficiency with which N-methyl-D-aspartate receptors (NMDARs) trigger intracellular signaling pathways governs neuronal plasticity, development, senescence, and disease. In cultured cortical neurons, suppressing the expression of the NMDAR scaffolding protein PSD-95 (postsynaptic density-95) selectively attenuated excitotoxicity triggered via NMDARs, but not by other glutamate or calcium ion (Ca2+) channels. NMDAR function was unaffected, because receptor expression, NMDA currents, and 45Ca2+ loading were unchanged. Suppressing PSD-95 blocked Ca2+-activated nitric oxide production by NMDARs selectively, without affecting neuronal nitric oxide synthase expression or function. Thus, PSD-95 is required for efficient coupling of NMDAR activity to nitric oxide toxicity, and imparts specificity to excitotoxic Ca2+ signaling.


Assuntos
Cálcio/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Canais de Cálcio/metabolismo , Sobrevivência Celular , Células Cultivadas , Proteína 4 Homóloga a Disks-Large , Ativação Enzimática , Guanilato Quinases , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana , Camundongos , N-Metilaspartato/toxicidade , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I , Núcleosídeo-Fosfato Quinase/metabolismo , Oligodesoxirribonucleotídeos Antissenso , Técnicas de Patch-Clamp , Sistemas do Segundo Mensageiro , Transdução de Sinais
14.
Science ; 265(5175): 1087-90, 1994 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-8066445

RESUMO

DNA sequences for the gene encoding mitochondrial cytochrome oxidase I in a group of rodents (pocket gophers) and their ectoparasites (chewing lice) provide evidence for cospeciation and reveal different rates of molecular evolution in the hosts and their parasites. The overall rate of nucleotide substitution (both silent and replacement changes) is approximately three times higher in lice, and the rate of synonymous substitution (based on analysis of fourfold degenerate sites) is approximately an order of magnitude greater in lice. The difference in synonymous substitution rate between lice and gophers correlates with a difference of similar magnitude in generation times.


Assuntos
Evolução Biológica , Complexo IV da Cadeia de Transporte de Elétrons/genética , Ftirápteros/genética , Roedores/genética , Roedores/parasitologia , Animais , Sequência de Bases , Interações Hospedeiro-Parasita , Funções Verossimilhança , Mitocôndrias/enzimologia , Dados de Sequência Molecular , Mutação , Ftirápteros/classificação , Ftirápteros/enzimologia , Ftirápteros/fisiologia , Filogenia , Roedores/classificação , Roedores/metabolismo
15.
Clin Exp Immunol ; 151(1): 123-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17991292

RESUMO

Deleted in Malignant Brain Tumours 1 (DMBT1) is a secreted scavenger receptor cysteine-rich protein that binds and aggregates various bacteria and viruses in vitro. Studies in adults have shown that DMBT1 is expressed mainly by mucosal epithelia and glands, in particular within the respiratory tract, and plays a role in innate immune defence. We hypothesized that respiratory DMBT1 levels may be influenced by various developmental and clinical factors such as maturity, age and bacterial infection. DMBT1 levels were studied in 205 tracheal aspirate samples of 82 ventilated preterm and full-term infants by enzyme-linked immunosorbent assay. Possible effects of various clinical parameters were tested by multiple regression analysis. DMBT1 levels increased significantly with lung maturity (P < 0.0001 for both gestational and postnatal age) and in small-for-gestational-age infants (P = 0.0179). An increase of respiratory DMBT1 levels was detected in neonatal infections (P < 0.0001). These results were supported by Western blotting. Immunohistochemical analyses of archived newborn lung sections (n = 17) demonstrated high concentrations of DMBT1 in lungs of neonates with bacterial infections. Our data show that preterm infants are able to up-regulate DMBT1 in infection as an unspecific immune reaction.


Assuntos
Doenças Transmissíveis/metabolismo , Pulmão/metabolismo , Receptores de Superfície Celular/metabolismo , Infecções Respiratórias/metabolismo , Biomarcadores/análise , Western Blotting/métodos , Proteínas de Ligação ao Cálcio , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/imunologia , Proteínas de Ligação a DNA , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Desenvolvimento Fetal/fisiologia , Idade Gestacional , Glucocorticoides/uso terapêutico , Humanos , Imuno-Histoquímica , Indometacina/uso terapêutico , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Pulmão/embriologia , Pulmão/imunologia , Masculino , Análise Multivariada , Gravidez , Receptores de Superfície Celular/análise , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/imunologia , Proteínas Supressoras de Tumor
16.
Leukemia ; 21(9): 1971-6, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17597804

RESUMO

Centrosomes play fundamental roles in mitotic spindle organization, chromosome segregation and maintenance of genetic stability. Recently, we have shown that centrosome aberrations occur early in chronic myeloid leukemia (CML) and are induced by imatinib in normal fibroblasts in vitro. To investigate the influence of BCR-ABL on centrosomes, we performed long-term in vitro experiments employing the conditionally p210BCR-ABL-expressing (tetracycline-inducible promoter) human monocytic cell line U937p210BCR-ABL/c6 as a model of CML chronic phase. Centrosome hypertrophy was detectable after 4 weeks of transgene expression onset, increasing up to a rate of 25.7% aberrant cells within 13 weeks of propagation. This concurred with clonal expansion of aneuploid cells displaying a hyperdiploid phenotype with 57 chromosomes. Partial reversibility of centrosome aberrations (26-8%) was achieved under prolonged propagation (14 weeks) after abortion of induction and bcr-abl silencing using small interfering RNA. Therapeutic doses of imatinib did not revert the aberrant phenotype, but counteracted the observed reverting effect of bcr-abl gene expression switch off. Suggesting a mechanistic model that features distinct abl-related tyrosine kinase activity levels as essential determinants of centrosomal integrity, this is the first report mechanistically linking p210BCR-ABL oncoprotein activity to centrosomal hypertrophy.


Assuntos
Transformação Celular Neoplásica , Centrossomo/patologia , Aberrações Cromossômicas , Proteínas de Fusão bcr-abl/fisiologia , Regulação Leucêmica da Expressão Gênica , Aneuploidia , Antineoplásicos/farmacologia , Benzamidas , Centrossomo/efeitos dos fármacos , Centrossomo/fisiologia , Células Clonais , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib , Piperazinas/farmacologia , Pirimidinas/farmacologia , Células U937
17.
Radiologe ; 48(2): 166-70, 2008 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-18210059

RESUMO

In the last 40 years colonoscopy has been the gold standard in diagnosis of conditions affecting the large intestine. We see its main disadvantages in the necessity for intestinal preparation and in the pain not infrequently experienced by patients who are not sedated. Widespread use of sedation has made it possible to improve patient acceptance in recent years. Complications of colonoscopy are rare, and even the removal of large polyps is regarded as a safe procedure. One of the main problems of colonoscopy is that a large number of far from trivial polyps--up to 20% in the literature--are overlooked. New developments, such as higher resolution videochips and chromoendoscopy, lead to a better diagnostic yield, especially of flat lesions. The rapidly developing sector of interventional colonoscopy in particular will ensure that colonoscopy continues to have an important place in the management of illnesses affecting the large intestine.


Assuntos
Colite/diagnóstico , Neoplasias do Colo/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia/métodos , Programas de Rastreamento , Biópsia , Colite Ulcerativa/diagnóstico , Neoplasias do Colo/patologia , Neoplasias do Colo/cirurgia , Pólipos do Colo/patologia , Pólipos do Colo/cirurgia , Sedação Consciente , Doença de Crohn/diagnóstico , Diagnóstico Diferencial , Diarreia/etiologia , Hemorragia Gastrointestinal/etiologia , Humanos , Mucosa Intestinal/patologia , Obstrução Intestinal/etiologia , Aceitação pelo Paciente de Cuidados de Saúde , Gravação em Vídeo/métodos
18.
Cancer Gene Ther ; 13(1): 65-73, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16096652

RESUMO

The prognosis of peritoneal spread from gastrointestinal cancer and subsequent malignant ascites is poor, and current medical treatments available are mostly ineffective. Targeted chemotherapy with intraperitoneal prodrug activation may be a beneficial new approach. L293 cells were genetically modified to express the cytochrome P450 enzyme 2B1 under the control of a cytomegalovirus immediate early promoter. This CYP2B1 enzyme converts ifosfamide to its active cytotoxic compounds. The cells are encapsulated in a cellulose sulfate formulation (Capcell). Adult Balb/c mice were inoculated intraperitoneally with 1 x 10(6) colon 26 cancer cells, previously transfected with GFP to emit a stable green fluorescence, by injection into the left lower abdominal quadrant. Two or five day's later animals were randomly subjected to either i.p. treatment with ifosfamide alone or ifosfamide combined with microencapsulated CYP2B1-expressing cells. Peritoneal tumor volume and tumor viability were assessed 10 days after tumor inoculation by means of fluorescence microscopy, spectroscopy and histology. Early i.p. treatment with ifosfamide and CYP2B1 cells resulted in a complete response. Treatment starting on day 5 and single-drug treatment with ifosfamide resulted in a partial response. These results suggest that targeted i.p. chemotherapy using a combination of a prodrug and its converting enzyme may be a successful treatment strategy for peritoneal spread from colorectal cancer.


Assuntos
Citocromo P-450 CYP2B1/farmacologia , Composição de Medicamentos , Terapia Genética/métodos , Ifosfamida/uso terapêutico , Neoplasias Peritoneais/terapia , Animais , Citocromo P-450 CYP2B1/metabolismo , Ifosfamida/metabolismo , Ifosfamida/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Peritoneais/metabolismo , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Transfecção , Células Tumorais Cultivadas
19.
Leukemia ; 19(7): 1192-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15858613

RESUMO

Centrosome abnormalities are hallmarks of various cancers and have been implicated in chromosome missegregation, chromosomal instability, and aneuploidy. Since genetic instability is a common feature in chronic myeloid leukemia (CML), we sought to investigate whether centrosome aberrations occur and correlate with disease stage and cytogenetic findings in CML. We examined 34 CML samples including CD 34+Ph+cells of 18 newly diagnosed patients (chronic phase (CP)) and 16 blast crisis (BC) specimens by using a centrosome-specific antibody to pericentrin. All CP and BC samples displayed centrosome alterations as compared with corresponding CD 34+control cells. Centrosome abnormalities were detected in 29.1+/-5.9% of CP blasts and in 54.3+/-4.8% of BC blasts, but in only 2.4+/-1.1% of controls (P<0.0001). Additional karyotypic alterations to the t(9;22) translocation were found in only 1/18 CML-CP patients. In contrast, 11/16 (73%) CML-BC patients displayed additional karyotype alterations in 48.7% of analyzed cells, correlating with an abnormal centrosome status (P=0.0005). Our results indicate that centrosome defects are a common and early detectable feature in CML that may contribute to acquisition of chromosomal aberrations and aneuploidy. They may be considered as the driving force of disease progression and could serve as future prognostic markers.


Assuntos
Centrossomo , Instabilidade Cromossômica/genética , Aberrações Cromossômicas , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Centrossomo/patologia , Análise Citogenética , Progressão da Doença , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade
20.
Cancer Res ; 59(6): 1295-300, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10096562

RESUMO

Natural killer (NK) cells provide effective antitumoral activity in the blood stream of mice, leading to reduced metastasis. There are, however, tumor cells that metastasize despite the presence of an intact NK system. The capability of tumor cells to induce platelet aggregation, on the other hand, correlates with their enhanced metastatic potential. A counteractive role of platelets for the NK function in metastasis has never been conceived. Here we demonstrate for the first time that platelets directly protect tumor cells from NK lysis in vitro as well as in vivo. Using three different tumor cell lines in a mouse model of experimental metastasis, tumor seeding in the target organs was reduced when the host was platelet depleted, but only if the tumor cells were NK sensitive. Aggregation of platelets around tumor cells also inhibited in vitro NK tumorilytic activity. This protection of tumor cells by platelets was mouse strain independent and was equally observed with platelets from beta2-microglobulin-deficient mice, excluding a NK inhibitory function of MHC class I on platelets. Thus, even if tumor cells are NK susceptible and cytotoxic NK cells threaten their survival in the blood, platelets are capable of protecting them from cytolysis, thereby promoting metastasis. Surface shielding by platelet aggregates seems to be the main mechanism of this protection.


Assuntos
Plaquetas/imunologia , Células Matadoras Naturais/imunologia , Metástase Neoplásica/imunologia , Animais , Plaquetas/patologia , Citotoxicidade Imunológica , Feminino , Células Matadoras Naturais/patologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Transplante de Neoplasias , Células Tumorais Cultivadas
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