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2.
Eur Rev Med Pharmacol Sci ; 25(23): 7508-7515, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34919253

RESUMO

OBJECTIVE: In this study, the antidiabetic efficacy of Protaetia brevitarsis in alloxan-treated pancreatic islets and db/db mice was investigated. P. brevitarsis was tested for alloxan-mediated cytotoxicity and nitric oxide production in mice pancreatic islets. MATERIALS AND METHODS: The anti-diabetic effect of P. brevitarsis was also evaluated in db/db mice after 4 weeks of administration. Biochemical analysis, oral glucose tolerance test (OGTT), and pancreatic histological analysis were performed. RESULTS: P. brevitarsis displayed hypoglycemic activity in alloxan-treated mice pancreatic islets. Our results showed that P. brevitarsis protects pancreatic islets from cytotoxicity. Moreover, daily oral supplementation with P. brevitarsis for 4 weeks reduced plasma glucose levels without affecting body weight and food intake, elevated glucose tolerance in OGTT, improved blood lipid parameters, inhibited fat accumulation, and restored islet structure of db/db mice. CONCLUSIONS: The present study provided evidence for the anti­diabetic effect of P. brevitarsis in alloxan-treated pancreatic islets and db/db mice. These results suggest that P. brevitarsis may be used as an adjunctive anti-diabetic agent or as a functional food.


Assuntos
Produtos Biológicos/farmacologia , Besouros , Diabetes Mellitus Experimental/tratamento farmacológico , Ilhotas Pancreáticas/efeitos dos fármacos , Aloxano , Animais , Glicemia/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Teste de Tolerância a Glucose , Hipoglicemiantes/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo
3.
Benef Microbes ; 11(4): 361-373, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32755263

RESUMO

Excessive body fat and the related dysmetabolic diseases affect both developed and developing countries. The aim of this study was to investigate the beneficial role of a bacterial culture supernatant (hereafter: BS) of Lactobacillus and Bifidobacterium and their potential mechanisms of action on white-fat browning and lipolysis. For selection of four candidates among 55 Lactic acid producing bacteria (LAB) from human infant faeces, we evaluated by Oil Red O staining and Ucp1 mRNA quantitation in 3T3-L1 preadipocytes. The expression of browning and lipolysis markers was examined along with in vitro assays. The possible mechanism was revealed by molecular and biological experiments including inhibitor and small interfering RNA (siRNA) assays. In a mouse model, physiological, histological, and biochemical parameters and expression of some thermogenesis-related genes were compared among six experimental groups fed a high-fat diet and one normal-diet control group. The results allow us to speculate that BS treatment promotes browning and lipolysis both in vitro and in vivo. Moreover, the BS may activate thermogenic programs via a mechanism involving PKA-CREB signaling in 3T3-L1 cells. According to our data, we can propose that two LAB strains, Bifidobacterium longum DS0956 and Lactobacillus rhamnosus DS0508, may be good candidates for a dietary supplement against obesity and metabolic diseases; however, further research is required for the development as dietary supplements or drugs.


Assuntos
Bifidobacterium longum/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Obesidade/terapia , Termogênese/efeitos dos fármacos , Células 3T3-L1 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/patologia , Animais , Diferenciação Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipólise/efeitos dos fármacos , Lipólise/genética , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Obesidade/etiologia , Obesidade/genética , Obesidade/metabolismo , Oxirredução/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Termogênese/genética
4.
Osteoarthritis Cartilage ; 27(11): 1653-1662, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31306782

RESUMO

OBJECTIVE: The aim of this study was to investigate how bone microstructure within bone marrow lesions (BMLs) relates to the bone and cartilage across the whole human tibial plateau. DESIGN: Thirty-two tibial plateaus from patients with osteoarthritis (OA) at total knee arthroplasty and eleven age-matched non-OA controls, were scanned ex vivo by MRI to identify BMLs and by micro CT to quantitate the subchondral (plate and trabecular) bone microstructure. For cartilage evaluation, specimens were processed histologically. RESULTS: BMLs were detected in 75% of the OA samples (OA-BML), located predominantly in the anterior-medial (AM) region. In contrast to non-OA control and OA-no BML, in OA-BML differences in microstructure were significantly more evident between subregions. In OA-BML, the AM region contained the most prominent structural alterations. Between-group comparisons showed that the AM region of the OA-BML group had significantly higher histological degeneration (OARSI grade) (P < .0001, P < .05), thicker subchondral plate (P < .05, P < .05), trabeculae that are more anisotropic (P < .0001, P < .05), well connected (P < .05, P = n.s), and more plate-like (P < 0.05, P < 0.05), compared to controls and OA-no BML at this site. Compared to controls, OA-no BML had significantly higher OARSI grade (P < .0001), and lower trabecular number (P < .05). CONCLUSION: In established knee OA, both the extent of cartilage damage and microstructural degeneration of the subchondral bone were dependent on the presence of a BML. In OA-no BML, bone microstructural alterations are consistent with a bone attrition phase of the disease. Thus, the use of BMLs as MRI image-based biomarkers appear to inform on the degenerative state within the osteochondral unit.


Assuntos
Medula Óssea/patologia , Cartilagem Articular/patologia , Articulação do Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Microtomografia por Raio-X/métodos , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Int J Cosmet Sci ; 40(2): 157-164, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29369367

RESUMO

OBJECTIVE: This research examines the benefits of caffeine absorption on hair stiffness. To test hair stiffness, we have developed an evaluation method that is not only accurate, but also inexpensive. Our evaluation method for measuring hair stiffness culminated in a model, called the Stiffness-Angle Law, which describes the elastic properties of hair and can be widely applied to the development of hair care products. METHODS: Small molecules (≤500 g mol-1 ) such as caffeine can be absorbed into hair. A common shampoo containing 4% caffeine was formulated and applied to hair 10 times, after which the hair stiffness was measured. The caffeine absorption of the treated hair was observed using Fourier-transform infrared spectroscopy (FTIR) with a focal plane array (FPA) detector. Our evaluation method for measuring hair stiffness consists of a regular camera and a support for single strands of hair. After attaching the hair to the support, the bending angle of the hair was observed with a camera and measured. Then, the hair strand was weighed. The stiffness of the hair was calculated based on our proposed Stiffness-Angle Law using three variables: angle, weight of hair and the distance the hair was pulled across the support. RESULTS: The caffeine absorption was confirmed by FTIR analysis. The concentration of amide bond in the hair certainly increased due to caffeine absorption. After caffeine was absorbed into the hair, the bending angle and weight of the hair changed. Applying these measured changes to the Stiffness-Angle Law, it was confirmed that the hair stiffness increased by 13.2% due to caffeine absorption. CONCLUSION: The theoretical results using the Stiffness-Angle Law agree with the visual examinations of hair exposed to caffeine and also the known results of hair stiffness from a previous report. Our evaluation method combined with our proposed Stiffness-Angle Law effectively provides an accurate and inexpensive evaluation technique for measuring bending stiffness of human hair.


Assuntos
Cafeína/metabolismo , Cabelo , Cafeína/química , Humanos , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
6.
New Phytol ; 215(1): 187-201, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28370001

RESUMO

The evolutionarily conserved MAP65 family proteins bundle anti-parallel microtubules (MTs). In Arabidopsis thaliana, mutations in the MAP65-3 gene lead to serious defects in MT organization in the phragmoplast and cause failures in cytokinesis. However, the functions of other ArabidopsisMAP65 isoforms are largely unknown. MAP65 functions were analyzed based on genetic interactions among different map65 mutations. Live-cell imaging and immunolocalization experiments revealed dynamic activities of two closely related MAP65 proteins in dividing cells. The map65-4 mutation caused synthetic lethality with map65-3 although map65-4 alone did not cause a noticeable phenotype. Furthermore, the introduction of an extra copy of the MAP65-4 gene significantly suppressed defects in cytokinesis and seedling growth caused by map65-3 because of restoring MT engagement in the spindle midzone. During mitosis, MAP65-4 first appeared at the preprophase band and persisted at the cortical division site afterwards. It was also concentrated on MTs in the spindle midzone and the phragmoplast. In the absence of MAP65-3, MAP65-4 exhibited greatly enhanced localization in the midzone of developing phragmoplast. Therefore, we have uncovered redundant but differential contributions of MAP65-3 and MAP65-4 to engaging and bundling anti-parallel MTs in the phragmoplast and disclosed a novel action of MAP65-4 at the cortical cell division site.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/ultraestrutura , Divisão Celular , Proteínas Associadas aos Microtúbulos/fisiologia , Microtúbulos/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequência Conservada , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitose , Mutação
7.
Clin Radiol ; 72(8): 692.e9-692.e15, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28364952

RESUMO

AIM: To evaluate the incidence of adverse events and associated factors after radiofrequency ablation (RFA) in patients with hepatocellular carcinoma within 30 days. MATERIALS AND METHODS: The early complications that occurred within 30 days after RFA at a single institution from January 2000 to July 2010 were reviewed in order to evaluate the morbidity, mortality, and risk factors associated with the complications. In total, 1,211 patients (845 men, 70.5%) with a mean age of 68 years (range, 27-88 years) underwent 1,843 RFA procedures. RESULTS: The overall incidence rate of complications was 6.8% (125 cases). Major complications (n=36, 2%) included liver abscess (n=15, 0.8%), intraperitoneal bleeding (n=8, 0.4%), liver failure (n=5, 0.3%), variceal bleeding (n=3, 0.2%), haemothorax (n=2, 0.1%), cholecystitis (n=2, 0.1%), and bowel perforation (n=1, 0.1%). Among the minor complications (n=89, 4.8%), the most common was the post RFA syndrome accompanied by pain and fever (n=75, 4.1%). Other minor complications included significant pleural effusion (n=7, 0.4%), skin wound infection (n=4, 0.2%), and thermal injuries to the skin (n=3, 0.2%). Procedural infections significantly increased with tumour size (OR=1.379; 95% confidence interval [CI], 1.191-1.579; p<0.001), and multiple overlapping ablations (OR=1.118; 95% CI, 1.019-1.227, p=0.018). Thrombocytopenia (<50,000/µl), prothrombin time, and serum albumin level were significantly associated with post-RFA bleeding episodes (p=0.041, p=0.021, and p=0.003, respectively). The overall mortality rate was 0.3% (three cases of hepatic failure, two case of sepsis, and one case of renal failure). CONCLUSIONS: RFA is a safe and effective local treatment for hepatocellular carcinoma. Careful selection of patients and appropriate RFA planning could decrease procedural mortality and morbidity.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/efeitos adversos , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
8.
Eur J Clin Microbiol Infect Dis ; 36(4): 611-617, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27837326

RESUMO

The correlation between hip replacement (Hip-Repl) and chronic osteomyelitis (COM) has not been studied in Asian populations. Thus, we assessed Hip-Repl-related risk of developing COM via a population-based, nationwide, retrospective cohort study. The Hip-Repl cohort was obtained from Taiwan's Longitudinal Health Insurance Database 2000, and included patients who underwent Hip-Repl between 2000 and 2010; the control cohort was also selected from this database. Patients with a history of COM were excluded in both cohorts. We used univariate and multivariate Cox proportional hazards regression models to calculate the adjusted hazard ratios (aHRs) by age, sex, and comorbidities for developing COM. A total of 5349 patients who received a Hip-Repl and 10,372 matched controls were enrolled. In the Hip-Repl group, the risk for COM was 4.18-fold [95 % confidence interval (CI) = 2.24-7.80] higher than that in the control group after adjustment. For patients aged ≤65 years, the risk was 10.0-fold higher (95 % CI = 2.89-34.6). Furthermore, the risk was higher in the Hip-Repl cohort than in the non-Hip-Repl cohort, for both patients without comorbidity (aHR = 16.5, 95 % CI = 2.07-132.3) and those with comorbidity (aHR = 3.49, 95 % CI = 1.78-6.83). The impact of Hip-Repl on the risk for COM was greater among patients not using immunosuppressive drugs, and occurred during the first postoperative year. Patients who received Hip-Repl have an increased risk of developing COM. This risk was higher among males and patients aged 65 years or younger, and during the first postoperative year.


Assuntos
Artroplastia de Quadril/efeitos adversos , Osteomielite/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Estudos de Casos e Controles , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Fatores Sexuais , Taiwan/epidemiologia , Adulto Jovem
9.
J Dent Res ; 93(7): 685-90, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24850617

RESUMO

Glechoma hederacea (GH), commonly known as ground-ivy or gill-over-the-ground, has been extensively used in folk remedies for relieving symptoms of inflammatory disorders. However, the molecular mechanisms underlying the therapeutic action of GH are poorly understood. Here, we demonstrate that GH constituents inhibit osteoclastogenesis by abrogating receptor activator of nuclear κ-B ligand (RANKL)-induced free cytosolic Ca(2+) ([Ca(2+)]i) oscillations. To evaluate the effect of GH on osteoclastogenesis, we assessed the formation of multi-nucleated cells (MNCs), enzymatic activity of tartrate-resistant acidic phosphatase (TRAP), expression of nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), and [Ca(2+)]i alterations in response to treatment with GH ethanol extract (GHE) in primarily cultured bone marrow-derived macrophages (BMMs). Treatment of RANKL-stimulated or non-stimulated BMMs with GHE markedly suppressed MNC formation, TRAP activity, and NFATc1 expression in a dose-dependent manner. Additionally, GHE treatment induced a large transient elevation in [Ca(2+)]i while suppressing RANKL-induced [Ca(2+)]i oscillations, which are essential for NFATc1 activation. GHE-evoked increase in [Ca(2+)]i was dependent on extracellular Ca(2+) and was inhibited by 1,4-dihydropyridine (DHP), inhibitor of voltage-gated Ca(2+) channels (VGCCs), but was independent of store-operated Ca(2+) channels. Notably, after transient [Ca(2+)] elevation, treatment with GHE desensitized the VGCCs, resulting in an abrogation of RANKL-induced [Ca(2+)]i oscillations and MNC formation. These findings demonstrate that treatment of BMMs with GHE suppresses RANKL-mediated osteoclastogenesis by activating and then desensitizing DHP-sensitive VGCCs, suggesting potential applications of GH in the treatment of bone disorders, such as periodontitis, osteoporosis, and rheumatoid arthritis.


Assuntos
Lamiaceae , Osteoclastos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ligante RANK/efeitos dos fármacos , Fosfatase Ácida/efeitos dos fármacos , Animais , Células da Medula Óssea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/efeitos dos fármacos , Sinalização do Cálcio/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Citosol/efeitos dos fármacos , Di-Hidropiridinas/farmacologia , Relação Dose-Resposta a Droga , Células Gigantes/efeitos dos fármacos , Isoenzimas/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/efeitos dos fármacos , Fosfatase Ácida Resistente a Tartarato
10.
Oncogene ; 33(36): 4496-507, 2014 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-24608434

RESUMO

Metastasis is the predominant cause of death in breast cancer patients. Several lines of evidence have shown that microRNAs (miRs) can have an important role in cancer metastasis. Using isogenic pairs of low and high metastatic lines derived from a human breast cancer line, we have identified miR-149 to be a suppressor of breast cancer cell invasion and metastasis. We also identified GIT1 (G-protein-coupled receptor kinase-interacting protein 1) as a direct target of miR-149. Knockdown of GIT1 reduced migration/invasion and metastasis of highly invasive cells. Re-expression of GIT1 significantly rescued miR-149-mediated inhibition of cell migration/invasion and metastasis. Expression of miR-149 impaired fibronectin-induced focal adhesion formation and reduced phosphorylation of focal adhesion kinase and paxillin, which could be restored by re-expression of GIT1. Inhibition of GIT1 led to enhanced protein degradation of paxillin and α5ß1 integrin via proteasome and lysosome pathways, respectively. Moreover, we found that GIT1 depletion in metastatic breast cancer cells greatly reduced α5ß1-integrin-mediated cell adhesion to fibronectin and collagen. Low level of miR-149 and high level of GIT1 was significantly associated with advanced stages of breast cancer, as well as with lymph node metastasis. We conclude that miR-149 suppresses breast cancer cell migration/invasion and metastasis by targeting GIT1, suggesting potential applications of the miR-149-GIT1 pathway in clinical diagnosis and therapeutics.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ciclo Celular/metabolismo , Integrinas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias da Mama/metabolismo , Proteínas de Ciclo Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Integrinas/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Transdução de Sinais , Células Tumorais Cultivadas
11.
J Periodontal Res ; 46(6): 712-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21745208

RESUMO

BACKGROUND AND OBJECTIVE: Activation of sirtuin 1 (SIRT1) promotes the differentiation of keratinocytes and mesenchymal stem cells, but inhibits the differentiation of muscle and fat cells. However, the involvement of SIRT1 in the differentiation of human periodontal ligament cells into osteoblast-like cells remains unclear. To identify the role of SIRT1 in human periodontal ligament cells, we measured SIRT1 mRNA and SIRT1 protein levels during the osteoblastic differentiation of human periodontal ligament cells. Additionally, we investigated the effects of overexpressing and underexpressing SIRT1 on the differentiation of human periodontal ligament cells, and the signaling mechanisms involved. MATERIAL AND METHODS: Expression of SIRT1 and osteoblastic differentiation markers was assessed by RT-PCR, real-time PCR, Alizarin red staining and western blotting. RESULTS: Marked upregulation of SIRT1 mRNA and SIRT1 protein was observed in cells grown for 3 d in osteogenic induction medium (OM). Activation of SIRT1 using resveratrol and isonicotinamide stimulated osteoblastic differentiation in a dose-dependent manner, as assessed by the expression of mRNAs encoding alkaline phosphatase, osteopontin, osteocalcin, osterix and Runx2, and induced calcium deposition. In contrast, inhibition of SIRT1 using sirtinol, nicotinamide and gene silencing by RNA interference suppressed mineralization and the expression of osteoblast marker mRNAs. Further mechanistic studies revealed that resveratrol treatment increased the phosphorylation of Akt, adenosine monophosphate kinase (AMPK), Smad 1/5/8 and c-Jun N-terminal kinase, but reduced OM-induced activation of nuclear factor-κB. Conversely, application of sirtinol suppressed the phosphorylation of Akt, AMPK, Smad 1/5/8, p38, ERK and c-Jun N-terminal kinase, and enhanced nuclear factor-κB activity, in OM-stimulated cells. CONCLUSION: These data suggest that SIRT1 is a potent regulator of differentiation of human periodontal ligament cells and may have clinical implications for periodontal bone regeneration.


Assuntos
Osteoblastos/citologia , Osteogênese/genética , Ligamento Periodontal/citologia , Sirtuína 1/biossíntese , Sirtuína 1/fisiologia , Diferenciação Celular/genética , Linhagem Celular Transformada , Regulação da Expressão Gênica , Humanos , Regeneração/genética , Sirtuína 1/genética
12.
Br J Pharmacol ; 164(2b): 794-806, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21501144

RESUMO

BACKGROUND AND PURPOSE: NF-κB has been implicated as a therapeutic target for the treatment of rheumatoid arthritis. We previously synthesized a thiourea analogue, SPA0355, which suppressed NF-κB activity. Here we have assessed the anti-inflammatory and anti-arthritic effects of SPA0355. EXPERIMENTAL APPROACH: We evaluated the effects of SPA0355 on human rheumatoid fibroblast-like synoviocytes in vitro and on collagen-induced arthritis (CIA) in mice in vivo. KEY RESULTS: In vitro experiments demonstrated that SPA0355 suppressed chemokine production, matrix metalloproteinase secretion and cell proliferation induced by TNF-α in rheumatoid fibroblast-like synoviocytes. In addition, SPA0355 inhibited osteoclast differentiation induced by macrophage colony-stimulating factor and the receptor activator of NF-κB ligand, in bone marrow macrophages. Mice with CIA that were pretreated with SPA0355 had a lower cumulative disease incidence and severity of arthritis, based on hind paw thickness, radiological and histopathological findings, and inflammatory cytokine levels, than mice treated with vehicle. Mice treated with SPA0355, after the onset of CIA, also showed significantly decreased disease incidence and joint oedema. The in vitro and in vivo protective effects of SPA0355 were mediated by inhibition of the NF-κB signalling pathway. CONCLUSION AND IMPLICATIONS: Taken together, these results suggested that using SPA0355 to block the NF-κB pathway in rheumatoid joints reduced both the inflammatory responses and tissue destruction. Therefore, SPA0355 may have therapeutic value in preventing or delaying joint destruction in patients with rheumatoid arthritis.


Assuntos
Artrite Experimental/tratamento farmacológico , Benzoxazinas/farmacologia , Membrana Sinovial/efeitos dos fármacos , Tioureia/análogos & derivados , Animais , Anti-Inflamatórios/farmacologia , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quimiocinas/biossíntese , Quimiocinas/metabolismo , Citocinas/biossíntese , Citocinas/metabolismo , Edema/tratamento farmacológico , Edema/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Articulações/efeitos dos fármacos , Articulações/metabolismo , Articulações/patologia , Masculino , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos DBA , Camundongos Endogâmicos ICR , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Osteoclastos/patologia , Transdução de Sinais/efeitos dos fármacos , Membrana Sinovial/metabolismo , Membrana Sinovial/patologia , Tioureia/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Opt Express ; 18(8): 7886-92, 2010 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-20588629

RESUMO

Unusual x-ray focusing effect is reported for parabolic curved multi-plate x-ray crystal cavities of silicon consisting of compound refractive lenses (CRL). The transmitted beam of the (12 4 0) back reflection near 14.4388 keV from these monolithic silicon crystal devices exhibits extraordinary focusing enhancement, such that the focal length is reduced by as much as 18% for 2-beam and 56% for 24-beam diffraction from the curved crystal cavity. This effect is attributed to the presence of the involved Bragg diffractions, in which the wavevector of the transmitted beam is bent further when traversing several curved crystal surfaces.

14.
J Chem Phys ; 131(22): 224705, 2009 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-20001074

RESUMO

The atomic structure of the Ag/Ge(111)-(sq.rt.(3) x sq.rt.(3))R30 degrees surface is studied by scanning tunneling microscopy (STM) and the density functional theory (DFT) calculations. Our STM images have shown a structure which is different from the widely accepted honeycomb-chained-triangle (HCT) model before. The structure is similar to the inequivalent triangle (IET) model found for the Ag/Si(111)-(sq.rt.(3) x sq.rt(3))R30 degrees surface. This model proposed two types of silver triangles with different sizes in the unit cell, corresponding to the bright spots and the dark spots in the STM image. A distinguishable hexagonal pattern of the IET structure was well disclosed in the temperature range from 100 to 473 K in our STM studies for Ag/Ge(111)-(sq.rt.(3) x sq.rt.(3))R30 degrees. Furthermore, the result of the DFT calculations showed that the IET structure is 0.20 eV energetically more stable than the HCT model. Besides, the Ge triangles, which were not disclosed in earlier STM research, are found in this study.

15.
Br J Pharmacol ; 158(8): 1971-81, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19922538

RESUMO

BACKGROUND AND PURPOSE: Benzoxathiolone derivatives have shown anti-inflammatory and immunomodulatory potential in acne and psoriatic disorders. However, little is known about the molecular basis for these pharmacological effects. In this study, we decided to investigate the anti-inflammatory actions of a benzoxathiolone derivative LYR-71, 6-methyl-2-propylimino-6,7-dihydro-5H-benzo[1,3]oxathiol-4-one, in interferon (IFN)-gamma-activated macrophages. EXPERIMENTAL APPROACH: RAW 264.7 macrophages or primary macrophages, derived from bone marrow of C3H/HeJ mice, were stimulated with IFN-gamma in the presence of LYR-71. Nitric oxide (NO) or chemokine production was measured by Griess reaction or enzyme-linked immunosorbent assay. RAW 264.7 cells were used to examine the molecular mechanisms of LYR-71 in modulating IFN-gamma-induced inflammatory responses. KEY RESULTS: LYR-71 down-regulated IFN-gamma-induced transcription of inducible NO synthase, IFN-gamma-inducible protein-10 and the monokine induced by IFN-gamma genes in macrophages. This effect was mediated by uncoupling tyrosine phosphorylation of the signal transducer and activator of transcription (STAT)-1 in response to IFN-gamma. LYR-71 directly inhibited the in vitro catalytic activity of Janus kinase (JAK)-2. Further, the inhibitory actions of LYR-71 on IFN-gamma-induced STAT-1 phosphorylation and NO production were consistently abolished in the presence of peroxyvanadate, implying another target dependent on protein tyrosine phosphatase. CONCLUSIONS AND IMPLICATIONS: Taken together, LYR-71 could restrain IFN-gamma-induced inflammatory responses through uncoupling the tyrosine phosphorylation of STAT-1, an activation index of JAK-STAT-1 signalling, in macrophages. These results may provide a molecular mechanism underlying anti-inflammatory actions shown by benzoxathiolone derivatives.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Iminas/farmacologia , Macrófagos/efeitos dos fármacos , Fator de Transcrição STAT1/efeitos dos fármacos , Animais , Anti-Inflamatórios/farmacologia , Medula Óssea/metabolismo , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Inflamação/tratamento farmacológico , Inflamação/fisiopatologia , Interferon gama/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Óxido Nítrico/metabolismo , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT1/metabolismo , Tirosina/metabolismo
16.
Plant Cell ; 21(4): 1129-40, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19383896

RESUMO

Although cells of flowering plants lack a structurally defined microtubule-organizing center like the centrosome, organization of the spindles and phragmoplasts in mitosis is known to involve the evolutionarily conserved gamma-tubulin complex. We have investigated the function of Arabidopsis thaliana NEDD1, a WD40 repeat protein related to the animal NEDD1/GCP-WD protein, which interacts with the gamma-tubulin complex. The NEDD1 protein decorates spindle microtubules (MTs) preferentially toward spindle poles and phragmoplast MTs toward their minus ends. A T-DNA insertional allele of the single NEDD1 gene was isolated and maintained in heterozygous sporophytes, and NEDD1's function in cell division was analyzed in haploid microspores produced by the heterozygote. In approximately half of the dividing microspores exhibiting aberrant MT organization, spindles were no longer restricted to the cell periphery and became abnormally elongated. After mitosis, MTs aggregated between reforming nuclei but failed to appear in a bipolar configuration. Consequently, defective microspores did not form a continuous cell plate, and two identical nuclei were produced with no differentiation into generative and vegetative cells. Our results support the notion that the plant NEDD1 homolog plays a critical role in MT organization during mitosis, and its function is likely linked to that of the gamma-tubulin complex.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/citologia , Divisão Celular/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Microtúbulos/metabolismo , Arabidopsis/metabolismo , Arabidopsis/ultraestrutura , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/fisiologia , Microtúbulos/ultraestrutura , Mutagênese Insercional , Filogenia , Fuso Acromático/metabolismo , Fuso Acromático/fisiologia , Fuso Acromático/ultraestrutura
17.
Rheumatology (Oxford) ; 48(1): 45-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19056796

RESUMO

OBJECTIVE: MMP is a key enzyme in the degradation of extracellular matrices, and its expression plays important roles in inflammatory diseases. Cordycepin (3'-deoxyadenosine), a bioactive compound of Cordyceps militaris, has been shown to exhibit many pharmacological activities, such as anti-cancer, anti-inflammatory and anti-infection activities. In this study, we aimed at the inhibitory effect of cordycepin on IL-1beta-induced MMP-1 and MMP-3 expression as well as the molecular basis using RA synovial fibroblasts (RASFs). METHODS: RASFs were isolated from synovial tissue obtained from 12 patients with RA and cultured in monolayer. Expression of MMP-1 and MMP-3 was evaluated using western blotting and real-time PCR. Chemokines were analysed by ELISA. The phosphorylation of mitogen-activated protein kinase was measured by western blotting. Electrophoretic mobility shift assay was performed to evaluate binding activities of DNA to nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1). RESULTS: Cordycepin inhibited IL-1beta-induced MMP-1 and MMP-3 expressions in RASFs in a dose-dependent manner. Among various chemokines [such as monocyte chemoattractant protein-1 (MCP-1), GRO-alpha, regulated upon activation, normal T-cell expressed and presumably secreted (RANTES) and epithelial neutrophil activating peptide 78 (ENA-78)], cordycepin specifically blocked IL-1beta-induced ENA-78 production in RASF. Moreover, cordycepin significantly inhibited IL-1beta-induced p38/JNK and AP-1 activation, but not extracellular signal-regulated kinase (ERK) and NF-kappaB activation. CONCLUSIONS: Cordycepin is a potent inhibitor of IL-1beta-induced chemokine production and MMP expression and strongly blocks the p38/JNK/AP-1 signalling pathway in RASFs.


Assuntos
Antirreumáticos/farmacologia , Artrite Reumatoide/enzimologia , Desoxiadenosinas/farmacologia , Interleucina-1beta/antagonistas & inibidores , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 3 da Matriz/biossíntese , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocinas/biossíntese , Proteínas de Ligação a DNA/metabolismo , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Fibroblastos/patologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-1beta/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 3 da Matriz/genética , NF-kappa B/metabolismo , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/enzimologia , Membrana Sinovial/patologia , Fator de Transcrição AP-1/metabolismo , Regulação para Cima/efeitos dos fármacos
18.
Eur Respir J ; 31(3): 523-31, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18057050

RESUMO

Vascular endothelial growth factor (VEGF) is a mediator of airway inflammation and remodelling in asthma. Transforming growth factor (TGF)-beta(1) plays pivotal roles in diverse biological processes, including tissue remodelling and repair in a number of chronic lung diseases. However, there are few studies elucidating the interactions between VEGF and TGF-beta(1) in allergic airway disease. A murine model of allergic airway disease was used to define the mechanism by which VEGF induces subepithelial fibrosis and to investigate a potential relationship between VEGF and TGF-beta(1) and the mechanisms by which VEGF signalling regulates TGF-beta(1) expression in allergic airway disease. The ovalbumin (OVA)-inhaled murine model revealed the following typical pathophysiological features of allergic airway disease in the lungs: increased numbers of inflammatory cells of the airways, airway hyperresponsiveness, increased peribronchial fibrosis, and increased levels of VEGF and TGF-beta(1). Administration of VEGF inhibitors reduced the pathophysiological signs of allergic airway disease and decreased the increased TGF-beta(1) levels and peribronchial fibrosis, including phosphoinositide 3-kinase (PI3K) activity after OVA inhalation. In addition, the increased TGF-beta(1) levels and collagen deposition after OVA inhalation were decreased by administration of PI3K inhibitors. These results suggest that inhibition of vascular endothelial growth factor attenuates peribronchial fibrosis, at least when mediated by regulation of transforming growth factor-beta(1) expression through phosphoinositide 3-kinase/Akt pathway in a murine model of allergic airway disease.


Assuntos
Asma/imunologia , Asma/fisiopatologia , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/imunologia , Animais , Modelos Animais de Doenças , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fibrose Pulmonar/fisiopatologia , Transdução de Sinais , Fator de Crescimento Transformador beta1/imunologia , Fator A de Crescimento do Endotélio Vascular/fisiologia
20.
Langmuir ; 23(25): 12521-8, 2007 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-17973407

RESUMO

The adsorption and self-organized monolayers of trans,trans-distyrylbenzene (tt-DSB) and cis,cis-distyrylbenzene (cc-DSB) on Ag/Ge(111)-(sqr rt of 3 x sqr rt of 3)R30 degrees (Ag/Ge(111)-sqr rt of 3) were studied by low-temperature scanning tunneling microscopy (STM) in ultrahigh vacuum. tt-DSB and cc-DSB overlayers were prepared by vapor deposition at a substrate temperature of 200 K and imaged after the samples were cooled to 100 K. High-resolution images allow identification of the internal structure of individual tt-DSB molecules with three phenyl rings and their molecular arrangements on the Ag/Ge(111)-sqr rt of 3 surface. It is found that the intermolecular distance between two terminal phenyl rings in tt-DSB is about twice the lattice constant of Ag/Ge(111)-sqr rt of 3. Such a lattice match makes Ag/Ge(111)-sqr rt of 3 an ideal substrate for tt-DSB self-organization and the formation of a (3 x 1) overlayer unit cell. The structural model and the molecule registry corresponding to STM images for the adlayers of tt-DSB on Ag/Ge(111)-sqr rt of 3 are proposed and discussed. For cc-DSB adsorption on Ag/Ge(111)-sqr rt of 3, uniform molecular overlayers with two discernible molecular images corresponding to two major types of cc-DSB conformers were observed. The coexistence of multiple conformers and the mismatch of molecular dimension of cc-DSB with the substrate unit cell length limit the growth of large cc-DSB domains.


Assuntos
Derivados de Benzeno/química , Germânio/química , Microscopia de Tunelamento/métodos , Prata/química , Estirenos/química , Adsorção , Modelos Moleculares , Tamanho da Partícula , Estereoisomerismo , Propriedades de Superfície , Temperatura
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