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1.
Br J Dermatol ; 183(5): 909-919, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32037509

RESUMO

BACKGROUND: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a condition caused by a drug-induced immune response. Previous reports have found that CXCL10, also known as interferon-γ-induced protein (IP)-10, may participate in the pathogenesis of cutaneous adverse drug reactions. However, the exact role of IP-10 in DRESS and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) has remained unknown. OBJECTIVES: This comparative prospective cohort study aimed to ascertain the roles of the IP-10/CXCR3 axis in DRESS and SJS/TEN. METHODS: Plasma IP-10 levels were analysed, and univariate analyses were conducted to assess the relationship between IP-10, human herpesvirus (HHV)-6 reactivation and the development of long-term sequelae. We also performed immunohistochemical staining using skin specimens and flow cytometry to determine the expression of CXCR3 in peripheral blood mononuclear cells (PBMCs). RESULTS: Significantly higher plasma IP-10 levels were observed in patients with DRESS with long-term sequelae (effect size 0·81) and also in those with HHV-6 reactivation (effect size 0·83). By immunohistochemistry, more abundant IP-10+ and CXCR3+ cells were demonstrated in the skin lesions of patients with DRESS with HHV-6 reactivation. The percentages of CLA+  CXCR3+  CD4+ cells and CLA+  CXCR3+  CD8+ cells were also higher in the PBMCs of HHV-6-reactivated patients with DRESS than in those of patients with SJS/TEN. CONCLUSIONS: Higher plasma IP-10 levels are associated with the development of long-term sequelae in DRESS. Higher IP-10/CXCR3 expression in skin and more abundant CLA+  CXCR3+  CD4+ cells and CLA+  CXCR3+  CD8+ cells were observed in patients with DRESS with HHV-6 reactivation. The IP-10/CXCR3 axis is associated with HHV-6 reactivation and development of long-term sequelae in DRESS. What is already known about this topic? Elevated levels of interferon-γ-induced protein-10 (IP-10) have been observed in patients with drug reaction with eosinophilia and systemic symptoms (DRESS) and Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). Patients with DRESS tend to develop long-term autoimmune sequelae, including type 1 diabetes and autoimmune thyroiditis. IP-10 has been associated with these autoimmune diseases in previous studies. What does this study add? The patients with DRESS with HHV-6 reactivation exhibited higher levels of IP-10 in the plasma and skin than the patients with DRESS without HHV-6 reactivation and the patients with SJS/TEN. Patients with DRESS with higher plasma IP-10 levels tended to develop sequelae during long-term follow-up. What is the translational message? IP-10 is a useful biomarker to predict the development of long-term sequelae in patients with DRESS. Linked Comment: Belloón and Kardaun. Br J Dermatol 2020; 183:804-805.


Assuntos
Quimiocina CXCL10 , Síndrome de Hipersensibilidade a Medicamentos , Herpesvirus Humano 6 , Receptores CXCR3 , Síndrome de Stevens-Johnson , Humanos , Interferon gama , Leucócitos Mononucleares , Estudos Prospectivos , Ativação Viral
2.
Oncogene ; 36(31): 4405-4414, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28368406

RESUMO

The epithelial-mesenchymal transition (EMT) is an important process in the progression of cancer. However, its occurrence and mechanism of regulation are not fully understood. We propose a regulatory pathway in which spermatogenic leucine zipper 1 (SPZ1) promotes EMT through its transactivating ability in increasing TWIST1 expression. We compared the expression of SPZ1 and TWIST1 in specimens of hepatocarcinoma cells (HCCs) and non-HCCs. Expression of SPZ1 exhibited a tumor-specific expression pattern and a high correlation with patients' survival time, tumor size, tumor number and progression stage. Moreover, forced expression and knockdown of SPZ1 in hepatoma cells showed that SPZ1 was able to regulate the cellular proliferation, invasion, and tumorigenic activity in a TWIST1-dependent manner in vitro and in vivo. These data demonstrate that SPZ1, a newly dscribed molecule, transactivates TWIST1 promoters, and that this SPZ1-TWIST axis mediates EMT signaling and exerts significant regulatory effects on tumor oncogenesis.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Carcinoma Hepatocelular/patologia , Transição Epitelial-Mesenquimal , Neoplasias Hepáticas/patologia , Proteínas Nucleares/fisiologia , Proteína 1 Relacionada a Twist/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinogênese , Carcinoma Hepatocelular/etiologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Neoplasias Hepáticas/etiologia , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Proteína 1 Relacionada a Twist/genética
3.
Nanotechnology ; 27(46): 465101, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27731308

RESUMO

Using photoluminescent ZnO nanorods and carbohydrate marker SSEA-4, a novel cancer cell recognition system was developed. Immobilization of SSEA-4 antibodies (αSSEA-4) on ZnO nanorods was performed in buffer solution (pH = 7.1) over 2 h. The cancer cell line probes were fixed on the glass slide. One hundred microliters of ZnO-αSSEA-4 conjugates were deposited on the cell probe and exposed for 30 min. After washing photoluminescence spectra were recorded. Based on the developed methodology, ZnO-αSSEA-4 probes were tested on patient-derived breast and colorectal carcinoma cells. Our data clearly show that the carbohydrate SSEA-4 molecule is expressed on cancer cell lines and patient-derived cancer cells. Moreover, SSEA-4 targeted ZnO nanorods bind to the patient-derived cancer cells with high selectivity and the photoluminescence signal increased tremendously compared to the signal from the control samples. Furthermore, the photoluminescence intensity increase correlated with the extent of malignancy in the target cell population. A novel portable bioanalytical system, based on optical ZnO nanorods and fiber optic detection system was developed. We propose that carbohydrate SSEA-4 specific ZnO nanorods could be used for the development of cancer diagnostic biosensors and for targeted therapy.


Assuntos
Nanotubos , Anticorpos , Técnicas Biossensoriais , Humanos , Luminescência , Neoplasias , Óxido de Zinco
4.
J Endocrinol Invest ; 39(7): 785-91, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26886939

RESUMO

OBJECTIVE: To investigate the role and potential molecular mechanism of Galectin-3 (Gal-3) in the etiology of endometriosis-associated infertility. METHODS: We detected Gal-3 expression in eutopic endometrium from women with endometriosis-associated infertility and healthy women without endometriosis or infertility. We then evaluated Gal-3 expression in endometrial glandular epithelial cells (EECs) and endometrial stromal cells (ESCs) and investigated its response to hormone stimulation in EECs and ESCs from both groups of women. RESULTS: Results of real-time PCR and western blot analysis showed Gal-3 expression in both proliferative and secretory stages of the menstrual cycle decreased significantly in women with endometriosis-associated infertility compared to healthy women. The changes in expression of Gal-3 were more dramatic in EECs than ESCs. Moreover, estrogen (E2) and progesterone (P4) induced Gal-3 expression in EECs of healthy groups, and P4 was more significant than E2 and combined E2 and P4 (E2P4). However, in the endometriosis group, P4 failed to induce a similar increase in Gal-3 expression. CONCLUSIONS: Our results suggest that aberrant expression of Gal-3 might contribute to infertility in patients with endometriosis due to progesterone resistance.


Assuntos
Biomarcadores/sangue , Endometriose/diagnóstico , Galectina 3/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Infertilidade/complicações , Adulto , Western Blotting , Estudos de Casos e Controles , Células Cultivadas , Endometriose/etiologia , Endometriose/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Galectina 3/genética , Humanos , Técnicas Imunoenzimáticas , Infertilidade/tratamento farmacológico , Infertilidade/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo
5.
Eur Cell Mater ; 26: 179-94; discussion 194, 2013 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-24122653

RESUMO

Three-dimensional (3D) cellular spheroids have recently emerged as a new trend to replace suspended single cells in modern cell-based therapies because of their greater regeneration capacities in vitro. They may lose the 3D structure during a change of microenvironment, which poses challenges to their translation in vivo. Besides, the conventional microporous scaffolds may have difficulty in accommodating these relatively large spheroids. Here we revealed a novel design of microenvironment for delivering and sustaining the 3D spheroids. Biodegradable scaffolds with macroporosity to accommodate mesenchymal stem cell (MSC) spheroids were made by solid freeform fabrication (SFF) from the solution of poly(D,L-lactide-co-glycolide). Their internal surface was modified with chitosan following air plasma treatment in order to preserve the morphology of the spheroids. It was demonstrated that human MSC spheroids loaded in SFF scaffolds produced a significantly larger amount of cartilage-associated extracellular matrix in vitro and in NOD/SCID mice compared to single cells in the same scaffolds. Implantation of MSC spheroid-loaded scaffolds into the chondral defects of rabbit knees showed superior cartilage regeneration. This study establishes new perspectives in designing the spheroid-sustaining microenvironment within a tissue engineering scaffold for in vivo applications.


Assuntos
Cartilagem/fisiologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Regeneração , Esferoides Celulares/efeitos dos fármacos , Alicerces Teciduais/química , Adulto , Animais , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Matriz Extracelular/efeitos dos fármacos , Feminino , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Poliglactina 910/química , Poliglactina 910/farmacologia , Coelhos , Esferoides Celulares/fisiologia
6.
B-ENT ; 9(2): 101-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23909116

RESUMO

OBJECTIVE: To investigate the function of the auditory efferent system in patients with chronic idiopathic tinnitus, but normal pure-tone audiograms. METHODS: We studied 15 subjects with normal hearing that had experienced either unilateral or bilateral persistent tinnitus for at least 3 months. The ears of the 15 subjects were classified into tinnitus-positive-ear (TPE) and tinnitus-negative-ear (TNE) groups. The control-ear group (CE) comprised the ears of 15 subjects with normal hearing and no tinnitus. We measured different types of otoacoustic emissions (OAEs), including spontaneous (SOAEs), transient evoked (TEOAEs), and distortion product (DPOAEs). We also analyzed contralateral suppression of OAEs and auditory brainstem responses (ABRs). Data were compared among TPE, TNE, and CE groups. RESULTS: The data associated with cochlear mechanics, including the prevalence of SOAEs, the number of SOAE peaks, and the overall TEOAE responses in the absence of a contralateral stimulus, were not significantly different among the TPE, TNE, and CE groups. In the TPE group, contralateral stimuli failed to significantly suppress overall TEOAEs, and contralateral suppression of DPOAEs was significantly reduced over a limited frequency range. Furthermore, the TPE group showed prolonged latencies in waves III and V of ABRs. CONCLUSION: This study demonstrated that abnormal contralateral suppression of OAEs and ABRs indicated a dysfunction in the ipsilateral efferent medial olivocochlear system; this might play a role in normal-hearing tinnitus.


Assuntos
Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Emissões Otoacústicas Espontâneas/fisiologia , Zumbido/fisiopatologia , Adulto , Doença Crônica , Vias Eferentes/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Allergy ; 68(6): 780-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23621474

RESUMO

BACKGROUND: Exposure to environmental hormones, such as alkylphenols, has been suggested to be associated with the development of asthma, but the mechanism of action remains unclear. OBJECTIVE: This study examined the effect of 4-nonylphenol (NP), one of the most important alkylphenols, on conventional dendritic cells (cDCs) and adaptive T-cell responses. It also explored the role of aryl hydrocarbon receptor (AhR) in NP's effect. METHODS: NP-conditioned bone marrow-derived DCs (BM-DCs) and splenic CD11c(+) cDCs were assessed regarding function in a murine model under conditions relevant to route and level of exposure in humans. RESULTS: Our results showed that splenic cDCs from NP-exposed mice have potent Th2-skewing ability and secrete increased levels of IL-6 and TNF-α, but not IL-10 and IL-12, at baseline and after stimulation with LPS. Further, bone marrow-derived DCs were cultured in the presence of NP and showed similar cytokine pattern and influenced the antigen-specific T cells secreting significantly less IFN-γ. Importantly, NP-exposed mice developed more severe OVA-induced allergic lung inflammation compared with control group. Interestingly, in a congenic strain of mice carrying low-affinity, ligand-binding mutant AhR (AhR(d) ), NP's effect on DC functions and lung inflammation was not observed in vitro and in vivo. CONCLUSION: These results suggested that NP may disturb physiologic function of DCs through, in part, AhR-dependent mechanisms, supporting the importance of NP exposure on the regulation of DC functions and allergic inflammation.


Assuntos
Asma/induzido quimicamente , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Imunidade Adaptativa/efeitos dos fármacos , Animais , Asma/imunologia , Asma/metabolismo , Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Hidrocarboneto Arílico/metabolismo
8.
Acta Biomater ; 9(6): 6915-27, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23416581

RESUMO

Biomimetic nanostructures have a wide range of applications. In particular, biodegradable polymer nanostructures that mimic the subtleties of extracellular matrix may provide favorable cell interactions. In this study, a co-solvent system was developed to configure a thermodynamically metastable biodegradable polymer solution, from which novel nanostructured matrices subsequently formed via wet phase separation (quaternary) or a combination with thermally induced phase separation. Three-dimensional (3D) nanostructured porous matrices were further fabricated by combination with particle-leaching (100-300µm glucose). The new co-solvent system may generate matrices with reproducible nanostructures from a variety of biodegradable polymers such as poly(d,l-lactide) (PLA), poly(ε-caprolactone) (PCL) and PCL-based polyurethane. In vitro cell culture experiments were performed with mouse pre-osteoblasts (MC3T3-E1) and human bone marrow-derived mesenchymal stem cells (hBM-MSC) to evaluate the osteoinductive potential of PLA nanostructures. The results showed that nanofibrous (<100nm) membranes promoted the bone-related marker gene expression and matrix mineralization of MC3T3-E1 at 14days. Nanofibrous 3D matrices seeded with hBM-MSC without osteogenic induction supplements demonstrated a 2.5-fold increase in bone matrix deposition vs. the conventional microporous matrices after 14 and 21days. Antimicrobial nanofibers were further obtained by plasma-assisted coating of chitosan on PLA nanofibers. This study reveals a platform for fabricating novel biodegradable nanofibrous architecture, with potential in tissue regeneration.


Assuntos
Implantes Absorvíveis , Regeneração Tecidual Guiada/instrumentação , Nanofibras/química , Osteoblastos/citologia , Osteoblastos/fisiologia , Polímeros/química , Alicerces Teciduais , Células 3T3 , Animais , Materiais Biomiméticos/síntese química , Desenho de Equipamento , Análise de Falha de Equipamento , Matriz Extracelular/química , Teste de Materiais , Camundongos , Nanofibras/ultraestrutura , Osteogênese/fisiologia , Transição de Fase
9.
Int J Impot Res ; 23(2): 62-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21390046

RESUMO

The relationship between endogenous plasma testosterone and plasma lipids was assessed among 856 Taiwanese men ≧40 years old originally recruited for an epidemiological study of testosterone deficiency syndrome. Blood samples were drawn from fasting (n = 562) and non-fasting (n = 294) subjects between 0800 to 1100 hours. With adjustment of age, body mass index and sex hormone-binding globulin, the following results were shown: (i) triglyceride (TG) levels were negatively associated with quartile levels of testosterone, and the magnitudes of associations were greater for postprandial TGs than for fasting TGs; (ii) high-density lipoprotein cholesterol (HDL-C) levels were positively related to quartile levels of testosterone, but the associations became insignificant after further control of TGs; and (iii) the calculated low-density lipoprotein cholesterol (LDL-C) levels were positively associated with quartile levels of testosterone. Similar results were obtained in multivariate linear regression analyses with additional control of hypertension and diabetes. In these Taiwanese men, the favorable association of endogenous plasma testosterone with HDL-C counterbalances the unfavorable association of it with LDL-C, while the net influence of testosterone on plasma lipids for cardiovascular system was still in the beneficial direction due to its negative association with postprandial plasma TG levels.


Assuntos
Lipídeos/sangue , Testosterona/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Jejum/sangue , Humanos , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/metabolismo , Taiwan
10.
Oncogene ; 30(26): 2921-32, 2011 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21317926

RESUMO

Epstein-Barr virus (EBV) infection is associated with many human neoplasms, in which EBV-derived latent membrane protein-1 (LMP1) appears to be critical, but its exact oncogenic mechanism remains to be defined. To this end, our initial microarray analyses identified a LMP1-inducible gene, Ugene, originally characterized as a binding partner for uracil DNA glycosylase 2, which is highly expressed in malignant colon cancer. In this report, it was found that Ugene, designated herein as LMP1-induced protein (LMPIP), was induced, in a time-dependent manner, in EBV-infected peripheral blood mononuclear cells and LMP1-transfected 293 cells. Functionally, when compared with mock-transfected cells, overexpression of LMPIP in nasopharyngeal carcinoma (NPC) cell lines resulted in a decrease in reactive oxygen species production and maintained mitochondria membrane potential (Δψ) loss induced by H(2)O(2). The NPC cells transfected with LMPIP also showed a decrease in G1 population and an increase in the cell population in sub-G1 and multiploid phase, concomitant with increased levels of cell cycle activators, including cyclin D1 and CDK4. In contrast, silencing of LMPIP expression in the NPC tumor cell lines with short hairpin RNA interference revealed significantly decreased cell population at G1/S phase, while the number of cells in multiploid phase increased. Significantly, NPC cells with LMPIP knock-down also showed a decrease in tumorigenic and transforming activity induced by ectopic LMP1 expression, as determined by analyses of soft agar foci and tumor size in nude mice. Further, elevated LMPIP expression was also noted in cytoplasm and nuclei in EBV-infected NPC tumor cell mass and non-EBV-infected tumor cell lines. These results suggested that LMPIP may have an important mediator role in EBV-mediated neoplasm and may serve as a new target for therapy of tumors induced by EBV infection.


Assuntos
Proteínas de Transporte/fisiologia , Transformação Celular Viral/genética , Epistasia Genética/fisiologia , Infecções por Vírus Epstein-Barr/complicações , Proteínas de Neoplasias/fisiologia , Animais , Callithrix , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Células Cultivadas , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/patologia , Feminino , Regulação da Expressão Gênica/fisiologia , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Proteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Coelhos , Distribuição Tecidual , Transfecção , Transplante Heterólogo , Proteínas da Matriz Viral/genética
11.
Oncogene ; 29(12): 1787-97, 2010 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-20023698

RESUMO

To identify microRNAs (miRNAs) that may have a causal role in hepatocarcinogenesis, we used an animal model in which C57BL/6 mice fed choline-deficient and amino acid defined (CDAA) diet develop preneoplastic lesions at 65 weeks and hepatocellular carcinomas after 84 weeks. miRNA expression profiling showed significant upregulation of miR-181b and miR-181d in the livers of mice as early as 32 weeks that persisted at preneoplastic stage. The expression of tissue inhibitor of metalloprotease 3 (TIMP3), a tumor suppressor and a validated miR-181 target, was markedly suppressed in the livers of mice fed CDAA diet. Upregulation of hepatic transforming growth factor (TGF)beta and its downstream mediators Smad 2, 3 and 4 and increase in phospho-Smad2 in the liver nuclear extract correlated with elevated miR-181b/d in mice fed CDAA diet. The levels of the precursor and mature miR-181b were augmented on exposure of hepatic cells to TGFbeta and were significantly reduced by small interference RNA-mediated depletion of Smad4, showing the involvement of TGFbeta signaling pathway in miR-181b expression. Ectopic expression and depletion of miR-181b showed that miR-181b enhanced matrix metallopeptidases (MMP)2 and MMP9 activity and promoted growth, clonogenic survival, migration and invasion of hepatocellular carcinoma (HCC) cells that could be reversed by modulating TIMP3 level. Further, depletion of miR-181b inhibited tumor growth of HCC cells in nude mice. miR-181b also enhanced resistance of HCC cells to the anticancer drug doxorubicin. On the basis of these results, we conclude that upregulation of miR-181b at early stages of feeding CDAA diet promotes hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Fígado/fisiologia , Inibidores Teciduais de Metaloproteinases/genética , Fator de Crescimento Transformador beta/farmacologia , Regulação para Cima/efeitos dos fármacos , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Divisão Celular , Linhagem Celular Tumoral , Movimento Celular , Ensaio de Unidades Formadoras de Colônias , Dieta/efeitos adversos , Modelos Animais de Doenças , Humanos , Fígado/efeitos dos fármacos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , MicroRNAs/genética , Estadiamento de Neoplasias , Inibidor Tecidual de Metaloproteinase-3/genética , Inibidor Tecidual 4 de Metaloproteinase
12.
Acta Biomater ; 6(6): 2066-76, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20040388

RESUMO

Surface modification is a conventional approach in biomaterials development, but most of the modification processes are intricate and time inefficient. In this study, a convenient open air plasma treatment was employed to modify the surface of poly(d,l-lactide) (PLA). Chitosan and fibroblast growth factor 1 (FGF1) were sequentially grafted with the assistance of open air plasma treatment onto the PLA nerve conduits with designed micropores and surface microgrooves. Grafting of these components was verified by electron spectroscopy for chemical analysis. The modified nerve conduits showed enhanced ability in the repair of 10-mm sciatic nerve transection defects in rats. The sequential air plasma treatment can be a convenient way to introduce biocompatible (e.g., chitosan) and bioactive components (e.g., growth factors) onto the surface of biomaterials.


Assuntos
Materiais Biocompatíveis/química , Regeneração Tecidual Guiada/instrumentação , Neuropatia Ciática/patologia , Neuropatia Ciática/cirurgia , Alicerces Teciduais , Ar , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Gases , Regeneração Tecidual Guiada/métodos , Temperatura Alta , Masculino , Teste de Materiais , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Resultado do Tratamento
13.
J Biomater Sci Polym Ed ; 20(5-6): 605-18, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19323879

RESUMO

In order to develop new materials for biomedical and pharmaceutical applications, interpenetrating polymer networks (IPNs) based on poly(ethylene glycol) methyl ether acrylate (PEGMEA) and gelatin were synthesized. These two materials were cross-linked sequentially using N,N'-methylene bisacrylamide (NMBA) and glutaraldehyde (Glu). Two series of IPNs gels were synthesized by applying different amounts of PEGMEA and gelatin in the initial feed. Sequential IPNs were prepared by polymerizing and cross-linking PEGMEA in the presence of gelatin using redox initiators (e.g., ammonium peroxydisulfate (APS) and N,N,N',N'-tetramethyl ethylenediamine (TEMED)), as well as NMBA as the cross-linking agent. Gelatin in firm gel was then cross-linked with 1% glutaraldehyde. The swelling kinetics, mechanical properties and drug-release behavior of these IPNs were analyzed. The surface properties were examined by scanning electron microscopy. The results indicated that the swelling ratio decreased with an increase in the content of both PEGMEA and gelatin in the IPNs. PEGMEA/gelatin-based full-IPNs had a significantly higher shear modulus (G) and cross-linking density (rho) when the content of PEGMEA was increased. The drug loading was very high due to the full-IPN structure. The drug-release velocity was mainly affected by the content of PEGMEA.


Assuntos
Materiais Biocompatíveis/química , Portadores de Fármacos/química , Gelatina/química , Metacrilatos/química , Polietilenoglicóis/química , Materiais Biocompatíveis/síntese química , Fenômenos Biomecânicos , Cafeína/administração & dosagem , Reagentes de Ligações Cruzadas , Preparações de Ação Retardada , Portadores de Fármacos/síntese química , Hidrogéis/síntese química , Hidrogéis/química , Cinética , Teste de Materiais , Metacrilatos/síntese química , Microscopia Eletrônica de Varredura , Polietilenoglicóis/síntese química , Propriedades de Superfície
14.
Opt Express ; 16(12): 8748-54, 2008 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-18545588

RESUMO

Disordered GaN nanopillars of three different heights: 300, 550, and 720 nm are fabricated, and demonstrate broad angular and spectral antireflective characteristics, up to an incident angle of 60? and for the wavelength range of lambda=300-1800 nm. An algorithm based on a rigorous coupled-wave analysis (RCWA) method is developed to investigate the correlations between the reflective characteristics and the structural properties of the nanopillars. The broadband and omnidirectional antireflection arises mainly from the refractive-index gradient provided by nanopillars. Calculations show excellent agreement with the measured reflectivities for both s- and p- polarizations.


Assuntos
Gálio/química , Lentes , Modelos Químicos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fotometria/métodos , Simulação por Computador , Luz , Tamanho da Partícula , Refratometria , Espalhamento de Radiação
15.
Eur Respir J ; 31(6): 1313-21, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18256057

RESUMO

It is unknown whether formoterol and salmeterol, two long-acting beta(2)-adrenoreceptor agonists, have regulatory functions in the production of T-helper cell (Th) type 2- and Th1-related chemokines by monocytes and bronchial epithelial cells. In the present study, the effects of formoterol and salmeterol on lipopolysaccharide (LPS)-induced expression of the Th2-related chemokine macrophage-derived chemokine (MDC; CCL22) and the Th1-related chemokine interferon-gamma-inducible protein (IP)-10 (CXCL10) were investigated in a monocytic cell line, THP-1, and in human primary monocytes. In addition, their effects on the expression of the Th2-related chemokine thymus- and activation-regulated chemokine (TARC; CCL17) were evaluated in an epithelial cell line, BEAS-2B. Formoterol enhanced MDC but suppressed IP-10 production in monocytes induced by LPS. Higher doses of salmeterol were required to enhance LPS-induced MDC expression in THP-1 cells. Formoterol and salmeterol could significantly suppress TARC expression in BEAS-2B cells. These effects could be reversed by a selective beta(2)-adrenoreceptor antagonist, ICI-118551. Formoterol- and LPS-induced MDC expression was inhibited by budesonide. Both long-acting beta(2)-adrenoreceptor agonists suppressed thymus- and activation-regulated chemokine expression in bronchial epithelial cells mediated via beta(2)-adrenoreceptors. Formoterol at physiological concentrations could suppress lipopolysaccharide-induced T-helper cell type 1-related chemokine (interferon-gamma-inducible protein-10) but enhance T-helper cell type 2-related chemokine (macrophage-derived chemokine) expression in human monocytes. Long-acting beta(2)-adrenoreceptor agonists may increase T-helper cell type 2-related chemokine expression in monocytes and T-helper cell type 2 recruitment and, therefore, long-acting beta(2)-adrenoreceptor agonist monotherapy may not be an appropriate therapeutic option for asthma.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Albuterol/análogos & derivados , Quimiocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Etanolaminas/farmacologia , Macrófagos/efeitos dos fármacos , Proteínas ADAM/metabolismo , Albuterol/farmacologia , Brônquios/citologia , Brônquios/efeitos dos fármacos , Linhagem Celular , Quimiocina CCL17/metabolismo , Quimiocina CXCL10/metabolismo , Células Epiteliais/metabolismo , Fumarato de Formoterol , Humanos , Macrófagos/metabolismo , Xinafoato de Salmeterol , Células Th1/fisiologia , Células Th2/fisiologia , Proteínas Supressoras de Tumor/metabolismo
16.
Mech Dev ; 108(1-2): 213-6, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11578878

RESUMO

Members of the RING finger family are implicated in a variety of functions such as signal transduction, transcriptional regulation and other developmental processes. Using degenerate oligonucleotide primers corresponding to the RING domain, we isolated a novel RING finger gene from the mouse testis cDNA library, which was about 1.8 kb and was termed Trif (testis-specific ring finger). This deduced protein contains an N-terminal RING-finger, a B-box, and a C-terminal B-30.2-like domain, which make the Trif protein a member of the RING finger-B-box-coil-coil family. Northern blot analysis of adult multiple tissues indicated that Trif is expressed predominantly in the testis. Further analysis detected Trif transcripts in the testis from day 20 of the postnatal stage. In situ hybridization indicated that Trif is expressed in the round spermatids of the seminiferous tubules. These expression data suggest that Trif may play an important role in the regulation of spermatogenesis.


Assuntos
Proteínas de Ligação a DNA/genética , Espermátides/metabolismo , Testículo/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Espermatogênese/genética , Testículo/crescimento & desenvolvimento , Proteínas com Motivo Tripartido , Ubiquitina-Proteína Ligases , Dedos de Zinco/genética
18.
Mech Dev ; 100(2): 177-87, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11165476

RESUMO

We isolated a novel bHLH-Zip gene designated Spz1 from a mouse testis cDNA library. Spz1 is expressed specifically in the testis and epididymis. Immunofluorescence staining detected Spz1 protein in the nuclei of LFG6 Leydig cells. The ability of Spz1 protein to bind to the bHLH consensus-binding site, the E-box, was confirmed by EMSA, and a 9-bp asymmetric target site was identified by random selection and PCR amplification. Hormonal regulation of Spz1 was investigated and downregulation of Spz1 expression by testosterone and retinoic acid was found. This nuclear transcription factor may play a crucial role in spermatogenesis by regulating cell proliferation or differentiation through binding to specific DNA sequences like other bHLH-Zip molecules.


Assuntos
Testículo/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Sítios de Ligação , Northern Blotting , Western Blotting , Linhagem Celular , Núcleo Celular/metabolismo , Mapeamento Cromossômico , Cromossomos , Clonagem Molecular , DNA Complementar/metabolismo , Regulação para Baixo , Epididimo/metabolismo , Biblioteca Gênica , Imuno-Histoquímica , Hibridização In Situ , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Microscopia de Fluorescência , Modelos Genéticos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Testes de Precipitina , Ligação Proteica , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Células de Sertoli/metabolismo , Testosterona/farmacologia , Distribuição Tecidual , Fatores de Transcrição/química , Tretinoína/farmacologia
19.
Osteoporos Int ; 12(12): 1020-5, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11846327

RESUMO

We treated 116 healthy postmenopausal women (age 47-66 years, mean 57 years) in Taiwan with either raloxifene (RLX) 60 mg (n = 92) or 0.625 mg conjugated equine estrogen plus 5 mg medroxyprogesterone acetate (CCEP, n = 24) daily for 12 months in a randomized, double-masked, active-controlled fashion. The results showed that both regimens increased bone mineral density (BMD) at hip sites (means: RLX 2.5-4.9%, CCEP 4.6-7.9%, all p<0.005 compared with baseline), and the difference between the two regimens was not significant. The spinal BMD increased significantly in both groups (1.4% with RLX and 6.0% with CCEP, both p<0.01), and more with CCEP (p<0.003). Osteocalcin levels and urinary type I collagen C-telopeptide/creatinine ratios decreased significantly in both regimens, but the decreases were significantly larger with CCEP. Compared with baseline, both RLX and CCEP decreased the total cholesterol (median 4.9% and 8.6% respectively, p<0.001) and LDL-cholesterol (median 11% and 19% respectively, p<0.001), and increased HDL-cholesterol (median 8.6% and 10.7% respectively, p<0.01). Both regimens increased triglyceride levels (median 3.2% and 18.9% respectively, both p<0.05), although to a lesser extent with RLX than with CCEP (p<0.05). Only 3 subjects (3.3%) reported vaginal bleeding in the RLX group, as compared with 31% (7/22) with CCEP (p<0.05). We conclude that in healthy, postmenopausal Taiwanese women, RLX 60 mg given daily has favorable results in BMD, bone turnover and serum lipids, although the dosage we used showed a potency less than that of conventional CCEP.


Assuntos
Densidade Óssea/efeitos dos fármacos , Terapia de Reposição de Estrogênios , Pós-Menopausa/fisiologia , Cloridrato de Raloxifeno/farmacologia , Idoso , Método Duplo-Cego , Combinação de Medicamentos , Endométrio/anatomia & histologia , Endométrio/efeitos dos fármacos , Estrogênios Conjugados (USP)/farmacologia , Feminino , Articulação do Quadril/fisiologia , Humanos , Lipídeos/sangue , Vértebras Lombares/fisiologia , Acetato de Medroxiprogesterona/farmacologia , Pessoa de Meia-Idade , Congêneres da Progesterona/farmacologia , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Útero/anatomia & histologia , Útero/efeitos dos fármacos
20.
Biochem Pharmacol ; 60(12): 1865-73, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11108802

RESUMO

Solamargine, an herbal and molluscicidal medicine derived from Solanum incanum, is a steroidal alkaloid glycoside. To characterize the anticancer mechanism of solamargine on human hepatoma cells (Hep3B), changes of cell morphology, DNA content, and gene expression of cells after solamargine treatment were studied. The appearance in solamargine-treated cells of chromatin condensation, DNA fragmentation, and a sub-G(1) peak in a DNA histogram suggests that solamargine induces cell death by apoptosis. The maximum number of dead Hep3B cells was detected within 2 hr of incubation with constant concentrations of solamargine, and no further cell death was observed after an extended incubation with solamargine, indicating that the action of solamargine was irreversible. To determine the susceptibility of cell phases to solamargine-mediated apoptosis, Hep3B cells were synchronized at defined cell cycles by cyclosporin A, colchicine, and genistein, followed by solamargine treatment. The IC(50) values of solamargine for control, G(0)/G(1)-, M-, and G(2)/M-synchronized Hep3B cells were 5.0, > 10, 3.7, and 3.1 microg/mL, implying that cells in the G(2)/M phases are relatively susceptible to solamargine-mediated apoptosis. In addition, a parallel up-regulation of tumor necrosis factor receptor (TNFR)-I and -II on Hep3B cells was detected after solamargine treatment, and the solamargine-mediated cytotoxicity could be neutralized with either TNFR-I or -II specific antibody. Therefore, these results reveal that the actions of TNFR-I and -II on Hep3B cells may be independent, and both are involved in the mechanism of solamargine-mediated apoptosis.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Alcaloides de Solanáceas/farmacologia , Anticorpos/farmacologia , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos CD/imunologia , Apoptose , Carcinoma Hepatocelular , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Expressão Gênica/efeitos dos fármacos , Humanos , Receptores do Fator de Necrose Tumoral/biossíntese , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Células Tumorais Cultivadas
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