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1.
Br J Dermatol ; 184(1): 96-110, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32271938

RESUMO

BACKGROUND: Human hair is highly responsive to stress, and human scalp hair follicles (HFs) contain a peripheral neuroendocrine equivalent of the systemic hypothalamic-pituitary-adrenal (HPA) stress axis. Androgenetic alopecia (AGA) is supposed to be aggravated by stress. We used corticotropin-releasing hormone (CRH), which triggers the HPA axis, to induce a stress response in human ex vivo male AGA HFs. Caffeine is known to reverse testosterone-mediated hair growth inhibition in the same hair organ culture model. OBJECTIVES: To investigate whether caffeine would antagonize CRH-mediated stress in these HFs. METHODS: HFs from balding vertex area scalp biopsies of men affected by AGA were incubated with CRH (10-7 mol L-1 ) with or without caffeine (0·001% or 0·005%). RESULTS: Compared to controls, CRH significantly enhanced the expression of catagen-inducing transforming growth factor-ß2 (TGF-ß2) (P < 0·001), CRH receptors 1 and 2 (CRH-R1/2) (P < 0·01), adrenocorticotropic hormone (ACTH) (P < 0·001) and melanocortin receptor 2 (MC-R2) (P < 0·001), and additional stress-associated parameters, substance P and p75 neurotrophin receptor (p75NTR ). CRH inhibited matrix keratinocyte proliferation and expression of anagen-promoting insulin-like growth factor-1 (IGF-1) and the pro-proliferative nerve growth factor receptor NGF-tyrosine kinase receptor A (TrkA). Caffeine significantly counteracted all described stress effects and additionally enhanced inositol trisphosphate receptor (IP3 -R), for the first time detected in human HFs. CONCLUSIONS: These findings provide the first evidence in ex vivo human AGA HFs that the stress mediator CRH induces not only a complex intrafollicular HPA response, but also a non-HPA-related stress response. Moreover, we show that these effects can be effectively antagonized by caffeine. Thus, these data strongly support the hypothesis that stress can impair human hair physiology and induce hair loss, and that caffeine may effectively counteract stress-induced hair damage and possibly prevent stress-induced hair loss.


Assuntos
Hormônio Liberador da Corticotropina , Receptor Tipo 2 de Melanocortina , Hormônio Adrenocorticotrópico/metabolismo , Androgênios , Cafeína/farmacologia , Hormônio Liberador da Corticotropina/metabolismo , Folículo Piloso/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Sistema Hipófise-Suprarrenal/metabolismo , Receptores Proteína Tirosina Quinases , Receptores de Fator de Crescimento Neural , Couro Cabeludo/metabolismo , Substância P
2.
Sci Adv ; 6(20): eaaz9165, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32426502

RESUMO

Dopaminergic neuronal cell death, associated with intracellular α-synuclein (α-syn)-rich protein aggregates [termed "Lewy bodies" (LBs)], is a well-established characteristic of Parkinson's disease (PD). Much evidence, accumulated from multiple experimental models, has suggested that α-syn plays a role in PD pathogenesis, not only as a trigger of pathology but also as a mediator of disease progression through pathological spreading. Here, we have used a machine learning-based approach to identify unique signatures of neurodegeneration in monkeys induced by distinct α-syn pathogenic structures derived from patients with PD. Unexpectedly, our results show that, in nonhuman primates, a small amount of singular α-syn aggregates is as toxic as larger amyloid fibrils present in the LBs, thus reinforcing the need for preclinical research in this species. Furthermore, our results provide evidence supporting the true multifactorial nature of PD, as multiple causes can induce a similar outcome regarding dopaminergic neurodegeneration.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Amiloide/metabolismo , Animais , Humanos , Corpos de Lewy/química , Corpos de Lewy/metabolismo , Corpos de Lewy/patologia , Doença de Parkinson/metabolismo , Primatas
3.
Nutr Metab Cardiovasc Dis ; 28(11): 1133-1139, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30143406

RESUMO

AIMS: To examine the association between wine consumption and the prevalence of chronic kidney disease (CKD) and cardiovascular disease (CVD). DATA SYNTHESIS: We performed a cross-sectional logistic regression analysis of National Health and Nutrition Examination Survey (NHANES) in participants 21 years of age or older from 2003 to 2006 in a large representative study of the U.S. POPULATION: Wine consumption was categorized as none (0 glass per day), light (<1 glass per day), or moderate (≥1 glasses per day). Prevalent CKD was defined as a urine albumin/creatinine ratio (UACR) ≥30 mg/g or estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2. CVD was defined as history of CVD including angina, myocardial infarction, or stroke. Only 27 (0.5%) individuals reported moderate wine consumption, whereas 57.5% and 42% reported abstinence and light wine consumption, respectively. Light wine consumption was associated with a lower prevalence of CKD as opposed to abstinence in unadjusted analysis. After adjusting for demographics and CVD risk factors light wine consumption was associated with lower prevalence of CKD defined as UACR ≥30 mg/g but not with low eGFR. Furthermore, light wine consumption was associated with significantly lower rates of CVD in the general population and in subjects with CKD. The adjusted odd of CVD for those with light wine consumption was 0.72 (CI 0.52-0.99, p = 0.046) for the subjects with CKD. CONCLUSION: These data suggest that light wine consumption (compared to abstinence) is associated with lower prevalence of CKD and a lower odd of CVD in those with CKD in the U.S.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Insuficiência Renal Crônica/epidemiologia , Vinho , Adulto , Albuminúria/epidemiologia , Albuminúria/fisiopatologia , Albuminúria/prevenção & controle , Abstinência de Álcool , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , Prognóstico , Fatores de Proteção , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/prevenção & controle , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
4.
Eur Cell Mater ; 33: 1-12, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-28054333

RESUMO

Atrophic non-unions are a major clinical problem. Mineral coated microparticles (MCM) are electrolyte-coated hydroxyapatite particles that have been shown in vitro to bind growth factors electrostatically and enable a tuneable sustained release. Herein, we studied whether MCM can be used in vivo to apply Bone Morphogenetic Protein-2 (BMP-2) to improve bone repair of atrophic non-unions. For this purpose, atrophic non-unions were induced in femurs of CD-1 mice (n = 48). Animals either received BMP-2-coated MCM (MCM + BMP; n = 16), uncoated MCM (MCM; n = 16) or no MCM (NONE; n = 16). Bone healing was evaluated 2 and 10 weeks postoperatively by micro-computed tomographic (µCT), biomechanical, histomorphometric and immunohistochemical analyses. µCT revealed more bone volume with more highly mineralised bone in MCM + BMP femurs. Femurs of MCM + BMP animals showed a significantly higher bending stiffness compared to other groups. Histomorphometry further demonstrated that the callus of MCM + BMP femurs was larger and contained more bone and less fibrous tissue. After 10 weeks, 7 of 8 MCM + BMP femurs presented with complete osseous bridging, whereas NONE femurs exhibited a non-union rate of 100 %. Of interest, immunohistochemistry could not detect macrophages within the callus, indicating a good biocompatibility of MCM. In conclusion, the local application of BMP-2-coated MCM improved bone healing in a challenging murine non-union model and, thus, should be of clinical interest in the treatment of non-unions.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Fraturas não Consolidadas/patologia , Microesferas , Minerais/farmacologia , Animais , Fenômenos Biomecânicos/efeitos dos fármacos , Líquidos Corporais/química , Proteína Morfogenética Óssea 2/administração & dosagem , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Calo Ósseo/efeitos dos fármacos , Calo Ósseo/patologia , Materiais Revestidos Biocompatíveis/administração & dosagem , Preparações de Ação Retardada , Fêmur/diagnóstico por imagem , Fêmur/efeitos dos fármacos , Fêmur/patologia , Fêmur/fisiopatologia , Fraturas não Consolidadas/fisiopatologia , Imuno-Histoquímica , Cinética , Camundongos , Microscopia Eletrônica de Varredura , Osteotomia , Microtomografia por Raio-X
5.
Ultramicroscopy ; 159 Pt 2: 413-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25980894

RESUMO

Due to their unique properties, nano-sized materials such as nanoparticles and nanowires are receiving considerable attention. However, little data is available about their chemical makeup at the atomic scale, especially in three dimensions (3D). Atom probe tomography is able to answer many important questions about these materials if the challenge of producing a suitable sample can be overcome. In order to achieve this, the nanomaterial needs to be positioned within the end of a tip and fixed there so the sample possesses sufficient structural integrity for analysis. Here we provide a detailed description of various techniques that have been used to position nanoparticles on substrates for atom probe analysis. In some of the approaches, this is combined with deposition techniques to incorporate the particles into a solid matrix, and focused ion beam processing is then used to fabricate atom probe samples from this composite. Using these approaches, data has been achieved from 10-20 nm core-shell nanoparticles that were extracted directly from suspension (i.e. with no chemical modification) with a resolution of better than ± 1 nm.

6.
Langmuir ; 26(21): 16381-91, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-20690654

RESUMO

The catalytic reduction of NO(2) with hydrogen on a Pt field emitter tip is investigated using both field electron microscopy (FEM) and field ion microscopy (FIM). A rich variety of nonlinear behavior and unusually high catalytic activity around the {012} facets are observed. Our FEM investigations reveal that the correlation function exhibits damped oscillations with a decaying envelope, showing that molecular noise will influence the dynamics of the oscillations. The dependence of the oscillatory period on the P(H(2))/P(NO(2)) pressure ratios is analyzed. Similar patterns are reported under FIM conditions. Corresponding density functional theory (DFT) calculations for the adsorption of NO(2) on Pt{012} in the presence of an external electric field are performed in order to gain an atomistic understanding of the underlying nonlinear phenomena.


Assuntos
Hidrogênio/química , Nanopartículas Metálicas/química , Dióxido de Nitrogênio/química , Platina/química , Adsorção , Catálise , Cinética , Microscopia Eletrônica , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
7.
Clin Exp Immunol ; 157(3): 332-42, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19664140

RESUMO

Plasmacytoid dendritic cells (pDCs) are of crucial importance in immune regulation and response to microbial factors. In multiple sclerosis (MS), pDCs from peripheral blood showed an immature phenotype, but its role in susceptibility to MS is not determined. Because infectious diseases are established triggers of exacerbations in MS, in this study we have characterized the expression of Toll-like receptors (TLR) and the maturation and functional properties of peripheral blood pDCs from clinically stable, untreated MS patients in response to signals of innate immunity. After stimulation of TLR-9, interferon (IFN)-alpha production by pDCs was significantly lower in MS (n = 12) compared to healthy controls (n = 9). In an allogenic two-step co-culture assay we found an impaired effect of TLR-9 stimulation on IFN-gamma expression of autologous naive T cells in MS patients (n = 4). In peripheral blood mononuclear cells, TLR-9 stimulation with type A CpG ODN resulted in a higher expression of TLR-1, -2, -4, -5 and -8 in MS patients (n = 7) compared with healthy controls (n = 11). These findings suggest an altered innate immune response to microbial stimuli in MS patients and may help understanding of why common infectious agents trigger MS attacks.


Assuntos
Infecções Bacterianas/imunologia , Células Dendríticas/imunologia , Esclerose Múltipla/imunologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Estudos de Casos e Controles , Células Dendríticas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Imunidade Inata , Imunização , Interferon gama/análise , Interferon gama/metabolismo , Leucaférese , Masculino , Esclerose Múltipla/metabolismo , Oligodesoxirribonucleotídeos/farmacologia , Reação em Cadeia da Polimerase/métodos , Estatísticas não Paramétricas , Receptor Toll-Like 9/agonistas , Receptores Toll-Like/análise , Receptores Toll-Like/metabolismo
8.
Brain ; 132(Pt 9): 2517-30, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19605531

RESUMO

Escalation therapy with mitoxantrone (MX) in highly active multiple sclerosis is limited by partially dose-dependent side-effects. Predictors of therapeutic response may result in individualized risk stratification and MX dosing. ATP-binding cassette-transporters ABCB1 and ABCG2 represent multi-drug resistance mechanisms involved in active cellular MX efflux. Here, we investigated the role of ABC-gene single nucleotide polymorphisms (SNPs) for clinical MX response, corroborated by experimental in vitro and in vivo data. Frequencies of ABCB1 2677G>T, 3435C>T and five ABCG2-SNPs were analysed in 832 multiple sclerosis patients (Germany, Spain) and 264 healthy donors. Using a flow-cytometry-based in vitro assay, MX efflux in leukocytes from individuals with variant alleles in both ABC-genes (designated genotype ABCB1/ABCG2-L(ow), 22.2% of patients) was 37.7% lower than from individuals homozygous for common alleles (ABCB1/ABCG2-H(igh), P < 0.05, 14.8% of patients), resulting in genotype-dependent MX accumulation and cell death. Addition of glucocorticosteroids (GCs) inhibited MX efflux in vitro. ABC-transporters were highly expressed in leukocyte subsets, glial and neuronal cells as well as myocardium, i.e. cells/tissues potentially affected by MX therapy. In vivo significance was further corroborated in experimental autoimmune encephalomyelitis in Abcg2(-/-) animals. Using a MX dose titrated to be ineffective in wild-type animals, disease course and histopathology in Abcg2(-/-) mice were strongly ameliorated. Retrospective clinical analysis in MX monotherapy patients (n = 155) used expanded disability status scale, relapse rate and multiple sclerosis functional composite as major outcome parameters. The clinical response rate [overall 121 of 155 patients (78.1%)] increased significantly with genotypes associated with decreasing ABCB1/ABCG2-function [ABCB1/ABCG2-H 15/24 (62.5%) responders, ABCB1/ABCG2-I(ntermediate) 78/98 (79.6%), ABCB1/ABCG2-L 28/33 (84.8%), exact Cochran-Armitage test P = 0.039]. The odds ratio for response was 1.9 (95% CI 1.0-3.5) with each increase in ABCB1/ABCG2 score (from ABCB1/ABCG2-H to -I-, and -I to -L). In 36 patients with severe cardiac or haematological side effects no statistically relevant difference in genotype frequency was observed. However, one patient with biopsy proven cardiomyopathy only after 24 mg/m2 MX exhibited a rare genotype with variant, partly homozygous alleles in 3 ABC-transporter genes. In conclusion, SNPs in ABC-transporter genes may serve as pharmacogenetic markers associated with clinical response to MX therapy in multiple sclerosis. Combined MX/GC-treatment warrants further investigation.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Mitoxantrona/uso terapêutico , Esclerose Múltipla/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/biossíntese , Adulto , Animais , Resistência a Múltiplos Medicamentos/genética , Quimioterapia Combinada , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/genética , Feminino , Regulação da Expressão Gênica , Frequência do Gene , Marcadores Genéticos , Genótipo , Glucocorticoides/uso terapêutico , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Mitoxantrona/efeitos adversos , Mitoxantrona/farmacocinética , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Proteínas de Neoplasias/biossíntese , RNA Mensageiro/genética , Estudos Retrospectivos , Resultado do Tratamento
9.
Ultramicroscopy ; 109(5): 619-24, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19135308

RESUMO

The surface composition of an Au-62at%Pd alloy has been studied by means of a catalytic atom probe (CAP) before and after exposures to nitric oxide (NO) at temperatures ranging from 300 to 573K for 20min. Subsequent CAP analysis at 100K revealed a considerable surface enrichment in Pd (to approximately 80at%) after exposure at 573K. This is correlated with the occurrence of NO dissociation, and the formation of strong Pd-O bonds at the surface. Blank experiments in ultra-high vacuum reflect the surface composition of the bulk material, in excellent agreement with electron microprobe analysis. At 573K, no detectable surface segregation occurs in the absence of NO adsorption for the times and temperatures studied. However, classical Metropolis Monte-Carlo simulations performed with a semi-empirical potential on the Au(40)Pd(60) (111), (110) and (100) systems show surface enrichment of gold at equilibrium. This suggests that the temperatures of the clean surface segregation experiments are too low to reach equilibrium within times of the order of hours.

10.
Ultramicroscopy ; 109(5): 381-4, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18995966

RESUMO

We present a study of the early stages of carbon nanotubes nucleation in CVD synthesis by combining field ion/electron emission microscopy (FIM/FEM) and atom-probe investigation (AP) of the nickel-carbon interaction. Acetylene decomposition on Ni tips at 873K is observed to induce additional step formation on an initially facetted (polyhedral) crystal. Carbon-enriched steps are then observed to act as preferential nucleation centers of graphene sheets formation. Atom-probe experiments reveal C(2) and C(3) species and frequency dependent studies demonstrate that the origin of these species is different from C(1). Experiments provide clear evidence for the crucial role of carbon-enriched steps as nucleation sites of graphene sheets on the Ni surface.

11.
J Chem Phys ; 125(5): 054703, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942237

RESUMO

We have studied oxygen interaction with Au crystals (field emitter tips) using time-resolved (atom-probe) field desorption mass spectrometry. The results demonstrate no adsorption to take place on clean Au facets under chosen conditions of pressures (p < 10(-4) m/bar) and temperatures (T = 300-350 K). Steady electric fields of 6 V/nm do not allow dissociating the oxygen molecule. The measured O2+ intensities rather reflect ionization of O2 molecules at critical distances above the Au tip surface. Certain amounts of Au-O2 complex ions can be found at the onset of Au field evaporation. Calculations by density functional theory (DFT) show weak oxygen end-on interaction with Au10 clusters (Delta E = 0.023 eV) and comparatively stronger interaction with Au1/Au(100) model surfaces (Delta E = 0.25 eV). No binding is found on {210} facets. Including (positive) electric fields in the DFT calculations leads to an increase of the activation energy for oxygen dissociation thus providing an explanation for the absence of atomic oxygen ions from the field desorption mass spectra.

12.
J Chem Phys ; 125(5): 054704, 2006 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-16942238

RESUMO

We report a study of the adsorption and reaction of CO on a gold nanotip in high electrostatic fields. Field ion microscopy is used to investigate the emergence of a Au-carbonyl wave that is made visible with oxygen as the imaging gas. We set up a simple kinetic model that reproduces the adsorption wave and confirms that the presence of oxygen merely serves as an imaging gas and does not lead to field-induced oxidation of CO.

13.
J Environ Sci Health B ; 41(4): 345-56, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16753954

RESUMO

Sorgoleone (SGL) exuded by sorghum roots inhibits the development of some weeds. Due to its high hydrophobicity, it is expected that SGL presents low soil mobility and limited allelopathic activity in the field. This work aims to evaluate the sorptivity of sorgoleone in octanol-water and in soil under two solvent systems. The two solvent systems were methanol:water (60:40) (MeOH:H2O) and pure methanol (MeOH). These two solvent systems promote different conditions for SGL solubility. Treatments were arranged in a 2 x 6 factorial (solvent systems x equilibrium concentrations in the solution (EC)). For each solvent, the sorption was achieved by shaking 500 mg of soil with 10 ml of 0, 5, 10, 15, 25, 40, and 60 mg L-1 of SGL solution, during 24 h. After centrifugation, the supernatant was filtered and the SGL concentration was determined by high performance liquid chromatography (HPLC). Data of sorbed amount of SGL were submitted to variance analysis, using a hierarchic factorial model. The data of sorbed amount (x/m) and equilibrium concentration (C) were fitted to the linear (x/m = a + KdC) and to the Freundlich (x/m = KfC1/n) models. The isotherm obtained for the MeOH:H2O system presented linear shape, whereas for the MeOH system a two subsequent linear isotherm was fitted. Sorgoleone is a highly hydrophobic compound, presenting a log Kow of 6.1. The sorption of sorgoleone to the soil was very high. The organic environment stimulated the sorgoleone sorption to the soil.


Assuntos
Benzoquinonas/química , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Modelos Químicos , Solo/análise , Solventes/química , Adsorção , Análise de Variância , Cromatografia Líquida de Alta Pressão/métodos , Relação Dose-Resposta a Droga , Modelos Lineares , Metanol/química , Solubilidade , Sorghum , Água/química
14.
J Neuroimmunol ; 165(1-2): 161-5, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15932772

RESUMO

In multiple sclerosis patients, infection is often associated with disease deterioration. Lipopolysaccharide (LPS) from gram-negative bacteria signals via the toll-like receptor 4 (TLR-4) pathway. Therefore, we investigated the role of an Asp299Gly mutation in the TLR-4 receptor in 890 MS patients with multiple sclerosis and 350 healthy controls. No association of different genotypes with MS susceptibility, MS subtypes, or disease severity was found. In vitro LPS stimulation studies showed a significantly lower proliferation of PBMCs from donors heterozygous for the Asp299Gly mutation in comparison to PBMCs from individuals with the wild-type genotype (p=0.01). However, these functional changes seem not to have any impact on the clinical presentation of MS patients with different TLR-4 genotypes.


Assuntos
Ácido Aspártico/genética , Glicina/genética , Glicoproteínas de Membrana/genética , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Polimorfismo Genético , Receptores de Superfície Celular/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , Citocinas/biossíntese , Progressão da Doença , Alemanha , Humanos , Isoleucina/genética , Glicoproteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Receptores de Superfície Celular/biossíntese , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Treonina/genética , Receptor 4 Toll-Like , Receptores Toll-Like
15.
J Neurol ; 252(5): 526-33, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15895275

RESUMO

BACKGROUND: Subcutaneous IFNbeta-1b (Betaferon) is an established immunomodulatory treatment for relapsing remitting MS and active secondary progressive multiple sclerosis (SPMS). It modulates cytokine and adhesion molecule expression but long term in vivo effects of IFNbeta-1b on the immune system are not known in multiple sclerosis. OBJECTIVE: To address the effects of IFNbeta-1b on serum levels for soluble adhesion molecules and cytokine receptors from MS patients. METHODS: Serial blood samples were obtained from 40 patients of the frequent MRI subgroup (20 patients each from the placebo and the IFNbeta-1b treatment group), participating in the European multi-center clinical trial with IFNbeta-1b for secondary progressive MS, at regular intervals for up to 36 months. Soluble adhesion molecules (sVCAM, sICAM-1, sL-Selectin) as well as TNF-receptor I and II were analysed in the serum of patients by enzyme linked immunosorbent assays (ELISAs). Monthly brain MRI was performed in 34 of these patients (16 patients from the placebo and 18 from the IFNbeta-1b group) during months 1-6 and 19-24 to monitor disease activity as assessed by newly occurring gadolinium (Gd) enhancing lesions. RESULTS: An early and significant increase in sVCAM and sTNF-RII serum levels was detected in 16 out of 20 patients (80 %) treated with subcutaneous IFNbeta-1b already at month 1 but was absent in all but one patient during placebo treatment (p < 0.01). Raised sVCAM and TNF RII serum levels during months 1-6 inversely correlated with less MRI activity in the 19-24 months treatment interval in the IFNa-1b treatment group ( p = 0.0093 for TNF-RII; p = 0.047 for VCAM). CONCLUSIONS: sVCAM and sTNF RII levels in the serum of SPMS patients are increased during IFNbeta-1b therapy and may at least in part explain some of the treatment effects, like reduced immune cell transmigration.


Assuntos
Interferon beta/uso terapêutico , Esclerose Múltipla Crônica Progressiva/sangue , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Molécula 1 de Adesão de Célula Vascular/sangue , Adulto , Método Duplo-Cego , Feminino , Humanos , Interferon beta-1b , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Crônica Progressiva/patologia , Estatísticas não Paramétricas
16.
J Phys Chem B ; 109(30): 14611-8, 2005 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-16852843

RESUMO

The surface composition of Al(2)O(3), V(2)O(5), and aluminovanadate oxide, "V-Al-O", was studied by X-ray photoelectron spectroscopy (XPS), using Mg K(alpha) to reveal time-dependent irradiation damage of samples. Spectral parameters such as peak intensity and width and absolute and relative peak binding energies were evaluated along with the Auger parameter. Irradiation of Al(2)O(3) was found to cause partial dehydration of the surface hydroxide film, while sputter-cleaned alumina turned out to be resistant to X-rays. In V(2)O(5), a small fraction of V(4+) species was seen to form during X-ray exposure. X-ray induced damage in Al(2)O(3) and V(2)O(5) was compared to that caused by bombardment with 500 eV argon ions. The V-Al-O material which is used as a precursor of oxynitride catalysts for ammoxidation turned out to be most susceptible and could be damaged by low X-ray doses. An appreciable reduction from the V(5+) to the V(4+) formal oxidation state (the latter increases from 20 to 45% after 150 min time of exposure to Mg K(alpha) at 150 W) was found along with the decomposition of aluminum hydroxide which is believed to act as an amorphous support in this catalyst. Gas-phase analysis during X irradiation demonstrated desorption of oxygen and water molecules. X-ray induced damage is believed to be caused by electron-hole pair generation and Auger decay rather than by thermal effects since the sample surface temperature increased only slightly.

17.
Clin Exp Rheumatol ; 22(3): 278-84, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15144120

RESUMO

OBJECTIVE: The importance of the presence of bacterial antigen or even living bacteria for the pathogenesis of reactive arthritis has been discussed increasingly ever since bacterial antigen was found in inflamed joints. Bacteria may persist in the body and drive the local immune response, maintaining arthritis. Cytokines, in particular tumor necrosis factor-alpha (TNF-alpha) are essential for bacterial elimination. In reactive arthritis, the course of the disease is influenced by several cytokines, including TNF-alpha. TNF-alpha expression can be mediated by transcription factor nuclear factor-kappa B (NF-kappaB). Moreover, TNF-alpha is also one of the strongest activators of NF-kappaB. METHODS: In vitro expression of TNF-alpha and activation of NF-kappaB in synovial fibroblasts after infection with Yersinia enterocolitica or Salmonella enteritidis was analysed by electrophoretic mobility shift assay, Western blot assay and real-time PCR. RESULTS: We found that infection of synovial fibroblasts with yersinia and salmonellae lead to the transient expression of TNF-alpha mRNA and induction of NF-kappaB. CONCLUSION: Induction of TNF-alpha in synovial fibroblasts after infection with yersiniae or salmonellae might be insufficient to eliminate bacteria, and this could allow the intracellular persistence of these bacteria. Our results therefore support the hypothesis that a permissive cytokine pattern might contribute to the pathogenesis of reactive arthritis.


Assuntos
Fibroblastos/microbiologia , NF-kappa B/biossíntese , Membrana Sinovial/microbiologia , Fator de Necrose Tumoral alfa/biossíntese , Yersinia enterocolitica/imunologia , Western Blotting , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Articulação do Joelho , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Salmonella enteritidis/imunologia , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia
18.
Neurosci Lett ; 335(3): 155-8, 2003 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-12531456

RESUMO

Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) exert various effects on immune cells. Here we studied, whether they influence the cytokine expression pattern in peripheral blood mononuclear cells (PBMCs) or antigen specific T-cells. In PBMCs BDNF and NGF had interindividually variable effects on T helper cell type (Th)1- and Th2-cytokines. However, there was a high correlation between the modulating properties of these neurotrophins (r=0.97) concerning the expression of interleukin (IL) 4, transforming growth factor-beta and tumour necrosis factor-alpha mRNA at a concentration of 100 ng/ml. In myelin basic protein-specific T-cell lines BDNF and NGF increased interferon -gamma mRNA to a moderate extent, but not IL4. No major effects were detected at the cytokine protein level. In conclusion, our results suggest a partial effect of neurotrophins on immune cells, which may be modified by other signals.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citocinas/metabolismo , Leucócitos Mononucleares/metabolismo , Fator de Crescimento Neural/metabolismo , Linfócitos T/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Técnicas de Cultura de Células , Citocinas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Interferon gama/metabolismo , Interleucina-4/metabolismo , Leucócitos Mononucleares/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , RNA Mensageiro/metabolismo , Linfócitos T/efeitos dos fármacos , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
19.
J Neurol Sci ; 200(1-2): 53-5, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12127676

RESUMO

In this pilot study, we serially determined the cytokine messenger RNA (mRNA) expression pattern in whole blood samples from 12 patients with clinical isolated syndrome suggestive of early multiple sclerosis (MS) using a new sensitive quantitative polymerase chain reaction (PCR) method. Significantly higher levels of tumor necrosis factor-alpha (TNF-alpha; x 5.1), interferon-gamma (IFN-gamma; x 4.8) and interleukin-10 (IL-10; x 5.6) mRNA were detected in MS patients at the time of a relapse compared to healthy controls. Treatment with i.v. methylprednisolone (MP) led to an increase of IL-4 mRNA and a significant decrease of IFN-gamma and TNF-alpha mRNA expression. In this cohort of clinically stable patients, proinflammatory cytokines remained low during the 1-year follow-up period. As several indications point to a cytokine dysregulation in MS, quantitative analysis of cytokine mRNA profiles in whole blood samples by real time PCR may be a useful immunological marker to monitor disease activity in future therapeutic trials in MS.


Assuntos
Citocinas/sangue , Esclerose Múltipla/sangue , RNA Mensageiro/sangue , Adulto , Citocinas/biossíntese , Feminino , Seguimentos , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , RNA Mensageiro/biossíntese , Estatísticas não Paramétricas
20.
Psychoneuroendocrinology ; 27(6): 671-81, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12084660

RESUMO

Depression is a common problem in multiple sclerosis (MS) and affects about 50% of MS patients. Since a dysregulation of cytokine levels has been implicated in the pathogenesis of MS and alterations in cytokine serum levels have been found in depressive illness, we examined the relationship between depressive symptoms, cytokine mRNA expression levels of Th1-type and Th2-type cytokines and neurological disability among early diagnosed MS patients in a prospective study. Sixteen patients with clinically or laboratory supported MS were assessed using the Beck Depression Inventory (BDI) and the Kurtzke Expanded Disability Status Scale (EDSS). Cytokine mRNA in whole blood was serially determined by a new quantitative polymerase chain reaction (PCR) method. BDI sum scores (2,9 fold) and the expression levels of tumor necrosis factor-alpha (TNF-alpha; 4 fold), interferon-gamma (IFN-gamma; 4,6 fold) and interleukin-10 (IL-10; 6,1 fold) mRNA were increased in MS patients during an acute attack compared to age and sex matched healthy controls. We detected a significant positive correlation between TNF-alpha (r=0.55) and interferon-gamma (r=0.54) mRNA expression and the BDI sum scores during an acute attack in MS patients. At follow-up after 3-6 months, only TNF-alpha mRNA expression was correlated with BDI sum scores (r=0.62 resp. r=0.31). No correlation of the BDI sum scores with Th2-type cytokine mRNA expression for interleukin-4 (IL-4) and interleukin-10 (IL-10) or with the extent of neurological disability was observed. The possible contribution of Th1-type cytokines to the development of depression in MS is discussed.


Assuntos
Depressão/sangue , Expressão Gênica , Interferon gama/genética , Esclerose Múltipla/complicações , RNA Mensageiro/sangue , Fator de Necrose Tumoral alfa/genética , Adulto , Depressão/classificação , Depressão/etiologia , Feminino , Humanos , Interleucina-10/genética , Masculino , RNA Mensageiro/genética
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