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1.
J Formos Med Assoc ; 116(6): 464-468, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27745798

RESUMO

BACKGROUND/PURPOSE: Cholangiocarcinoma (CC) is a fatal malignancy originating from biliary tracts and constitutes approximately 10-20% of hepatobiliary cancers. CC is characterized by a very poor prognosis. The definite molecular mechanisms leading to oncogenesis remain unclear. This study aimed to perform mutation analysis and copy number changes of KRAS and BRAF genes of CC in Taiwan. METHODS: A total of 182 cases of biliary tact CC were studied for point mutation and quantitative real-time polymerase chain reaction analysis of KRAS and BRAF genes. The obtained data were analyzed with clinical and histopathological variables and survival. RESULTS: KRAS point mutations were detected in intrahepatic CC (7.6%), common bile duct cancer (13.3%), and gallbladder carcinoma (3.3%). BRAF gene amplifications were demonstrated in intrahepatic CC (4.3%), common bile duct cancer (3.3%), and gallbladder cancer (5%). No association was observed between mutation patterns and histopathological features. The analyses of risk factors for overall survival in patients with CC revealed no significant association in age, tumor site, genetic mutation, or amplifications. The tumor stage was the significant prognostic factor. CONCLUSION: Unlike other studies from American, European, or Japanese groups which showed certain levels of gene mutations in CC, our data revealed a rather low frequency of KRAS mutations and BRAF gene amplifications in CC in Taiwan. Tumor TNM stage was the only significant prognostic parameter in this analysis. It is crucial to gain more information of carcinogenesis, molecular mechanisms and therapeutic strategy in biliary tract cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares/genética , Colangiocarcinoma/genética , Amplificação de Genes , Mutação Puntual , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Taiwan
2.
Acta Derm Venereol ; 95(6): 711-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25673333

RESUMO

Although anti-drug antibodies against biologics have been associated with decreased clinical efficacy, the immunogenicity of biologics seems to vary between drugs, diseases and ethnicities. This study aims to investigate the predictors for the formation of anti-adalimumab antibodies (AAA) and the clinical consequences of AAA formation. In 53 Chinese psoriatic patients treated with adalimumab, AAA was detected in 50.9%. Differences in Psoriasis Area and Severity Index 75 (PASI75) response rates among patients with and without AAA were significant (44.4% vs. 88.5%; p = 0.001). Patients with AAA had significantly lower trough concentrations of adalimumab than those without AAA. Risk factor analysis showed that treatment interruption, low trough adalimumab concentration, absence of concomitant methotrexate use and biologics switching were associated with a higher AAA titre. The treatment pattern of biologics influences the risk of AAA formation, thereby leading to reduced efficacy of adalimumab.


Assuntos
Adalimumab/imunologia , Anti-Inflamatórios não Esteroides/imunologia , Anticorpos/sangue , Resistência a Medicamentos/imunologia , Psoríase/tratamento farmacológico , Psoríase/imunologia , Adalimumab/administração & dosagem , Adalimumab/sangue , Adulto , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/sangue , China , Substituição de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
3.
Lasers Surg Med ; 47(1): 50-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25557083

RESUMO

BACKGROUND AND OBJECTIVES: Hair follicles are located at the interface of the external and internal environments and their cycling has been shown to be regulated by intra- and extra-follicular factors. The aim of this study is to examine whether or how hair follicles respond to visible light. STUDY DESIGN/MATERIALS AND METHODS: We examined the effect of 3 mW red (630 nm, 1 J/cm(2)), 2 mW green (522 nm, 1 J/cm(2)), and 2 mW blue light (463 nm, 1 J/cm(2)) on telogen in mice for 3 weeks. The photobiologic effects of red light on cell proliferation of outer root sheath keratinocytes and dermal papilla cells were studied in vitro. RESULTS: We found that red light accelerated anagen entry faster than green and blue light in mice. Red light irradiation stimulated the proliferation of both outer root sheath keratinocytes and dermal papilla cells in a dose-dependent manner by promoting cell cycle progression. This stimulative effect was mediated via extracellular signal-regulated kinase phosphorylation in both cells. In a co-culture condition, dermal papilla cells irradiated by red light further enhanced keratinocyte proliferation, suggesting enhanced epithelial-mesenchymal interaction. In search for factors that mediated this paracrine effect, we found fibroblast growth factor 7 was upregulated in both mRNA and protein levels. The stimulative paracrine effect on keratinocytes was significantly inhibited by neutralizing antibody against fibroblast growth factor 7. CONCLUSIONS: These results suggest that hair follicles respond to visible light in vivo. Red light may promote physiological telogen to anagen transition by directly stimulating outer root sheath keratinocytes and indirectly by enhancing epithelial-mesenchymal interaction in vitro.


Assuntos
Folículo Piloso/efeitos da radiação , Luz , Animais , Biomarcadores/metabolismo , Proliferação de Células/efeitos da radiação , Derme/metabolismo , Derme/efeitos da radiação , Feminino , Fator 7 de Crescimento de Fibroblastos/metabolismo , Cabelo/crescimento & desenvolvimento , Cabelo/efeitos da radiação , Folículo Piloso/fisiologia , Técnicas In Vitro , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória
4.
Nano Lett ; 12(7): 3437-42, 2012 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-22725714

RESUMO

Nanopores with conical geometries have been found to rectify ionic current in electrolytes. While nanopores in semiconducting membranes are known to modulate ionic transport through gated modification of pore surface charge, the fabrication of conical nanopores in silicon (Si) has proven challenging. Here, we report the discovery that gold (Au) nanoparticle (NP)-assisted plasma etching results in the formation of conical etch profiles in Si. These conical profiles result due to enhanced Si etch rates in the vicinity of the Au NPs. We show that this process provides a convenient and versatile means to fabricate conical nanopores in Si membranes and crystals with variable pore-diameters and cone-angles. We investigated ionic transport through these pores and observed that rectification ratios could be enhanced by a factor of over 100 by voltage gating alone, and that these pores could function as ionic switches with high on-off ratios of approximately 260. Further, we demonstrate voltage gated control over protein transport, which is of importance in lab-on-a-chip devices and biomolecular separations.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Nanoporos , Silício/química , Condutividade Elétrica , Membranas Artificiais , Tamanho da Partícula , Semicondutores
5.
Acta Cytol ; 54(5 Suppl): 867-70, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21053558

RESUMO

UNLABELLED: BACKGROUND; Primary non-Hodgkin's lymphoma of the breast is uncommon among primary malignant breast tumors. Here we present a case diagnosed as primary breast lymphoma with imprint cytology during intraoperative frozen consultation. CASE: A 67-year-old woman presented with a palpable, non-tender mass in her left breast that she had had for 2 weeks. The mammogram and ultrasound studies revealed 1 lobular mass in the left breast without axillary lymphadenopathy. Imprint cytology helped diagnose malignant lymphoma of the breast, preventing radical surgery. CONCLUSION: Frozen artifact may obscure the evaluation of cytomorphology during intraoperative consultation. Imprint cytology may help due to less artifact with the cytologic details. Primary breast lymphomas should be considered in the differential diagnosis of breast tumors. The current literature recommendation of intermediate to high grade lymphoma is combined partial mastectomy followed by chemotherapy with local radiotherapy.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Mama/patologia , Técnicas Citológicas/métodos , Secções Congeladas , Linfoma não Hodgkin/diagnóstico , Linfoma não Hodgkin/patologia , Idoso , Antígenos CD20/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Imuno-Histoquímica , Cuidados Intraoperatórios , Radiografia , Encaminhamento e Consulta , Ultrassonografia
8.
Biomaterials ; 167: 121-131, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29567388

RESUMO

Organ development is a sophisticated process of self-organization. However, despite growing understanding of the developmental mechanisms, little is known about how to reactivate them postnatally for regeneration. We found that treatment of adult non-hair fibroblasts with cell-free extract from embryonic skin conferred upon them the competency to regenerate hair follicles. Proteomics analysis identified three secreted proteins enriched in the embryonic skin, apolipoprotein-A1, galectin-1 and lumican that together were essential and sufficient to induce new hair follicles. These 3 proteins show a stage-specific co-enrichment in the perifolliculogenetic embryonic dermis. Mechanistically, exposure to embryonic skin extract or to the combination of the 3 proteins altered the gene expression to an inductive hair follicle dermal papilla fibroblast-like profile and activated Igf and Wnt signaling, which are crucial for the regeneration process. Therefore, a cocktail of organ-specific extracellular proteins from the embryonic environment can render adult cells competent to re-engage in developmental interactions for organ neogenesis. Identification of factors that recreate the extracellular context of respective developing tissues can become an important strategy to promote regeneration in adult organs.


Assuntos
Apolipoproteína A-I/metabolismo , Galectina 1/metabolismo , Folículo Piloso/fisiologia , Lumicana/metabolismo , Regeneração , Pele/embriologia , Animais , Células Cultivadas , Feminino , Fibroblastos/citologia , Fibroblastos/metabolismo , Folículo Piloso/citologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Ratos Wistar
9.
J Dermatol Sci ; 86(2): 114-122, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28117106

RESUMO

BACKGROUND: Hair follicle is miniorgan constituted by keratinocytes and its distinctive mesenchyme of dermal papilla. Its aging is characterized by organ atrophy and impaired stem cell activation and differentiation. The contribution of dermal papilla to hair follicle aging change is not well understood. OBJECTIVE: This work was aimed at exploring the possible role of premature dermal papilla senescence in the pathogenesis of hair follicle aging. METHODS: Dermal papilla cells were challenged with H2O2 to induce premature senescence and the proliferation, apoptosis, gene expression and protein secretion were characterized. Its effect on epithelial-mesenchymal interaction was analyzed by co-culture in vitro and implantation of protein-coated beads in vivo. RESULT: Dermal papilla cells were more resistant to oxidative stress-induced apoptosis than dermal fibroblasts. The surviving dermal papilla cells showed signs of senescence but still preserved key dermal papilla signature gene expression. In addition to the failure to respond to mitogenic stimulation from keratinocytes, they lost the ability to induce hair follicle neogenesis, promoted interfollicular epidermal differentiation, inhibited follicular differentiation and, importantly, suppressed clonal growth of hair follicle stem cells. They produced higher levels of multiple inflammatory cytokines, including IL-6. Functionally, IL-6 inhibited clonal keratinocyte growth in vitro and blocked the transition from telogen to anagen in vivo. CONCLUSION: Stress-induced premature dermal papilla senescence can contribute to hair follicle aging change due to compromised epithelial-mesenchymal interaction.


Assuntos
Senescência Celular , Transição Epitelial-Mesenquimal , Folículo Piloso/citologia , Folículo Piloso/patologia , Pele/patologia , Animais , Apoptose , Diferenciação Celular , Proliferação de Células , Técnicas de Cocultura , Citocinas/metabolismo , Derme/citologia , Derme/metabolismo , Epiderme/metabolismo , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Cabelo/crescimento & desenvolvimento , Peróxido de Hidrogênio/química , Interleucina-6/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Estresse Oxidativo , Ratos , Ratos Wistar , Regeneração , Pele/crescimento & desenvolvimento
10.
Cancer Res ; 77(22): 6083-6096, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28939680

RESUMO

Genotoxicity-induced hair loss from chemotherapy and radiotherapy is often encountered in cancer treatment, and there is a lack of effective treatment. In growing hair follicles (HF), quiescent stem cells (SC) are maintained in the bulge region, and hair bulbs at the base contain rapidly dividing, yet genotoxicity-sensitive transit-amplifying cells (TAC) that maintain hair growth. How genotoxicity-induced HF injury is repaired remains unclear. We report here that HFs mobilize ectopic progenitors from distinct TAC compartments for regeneration in adaptation to the severity of dystrophy induced by ionizing radiation (IR). Specifically, after low-dose IR, keratin 5+ basal hair bulb progenitors, rather than bulge SCs, were quickly activated to replenish matrix cells and regenerated all concentric layers of HFs, demonstrating their plasticity. After high-dose IR, when both matrix and hair bulb cells were depleted, the surviving outer root sheath cells rapidly acquired an SC-like state and fueled HF regeneration. Their progeny then homed back to SC niche and supported new cycles of HF growth. We also revealed that IR induced HF dystrophy and hair loss and suppressed WNT signaling in a p53- and dose-dependent manner. Augmenting WNT signaling attenuated the suppressive effect of p53 and enhanced ectopic progenitor proliferation after genotoxic injury, thereby preventing both IR- and cyclophosphamide-induced alopecia. Hence, targeted activation of TAC-derived progenitor cells, rather than quiescent bulge SCs, for anagen HF repair can be a potential approach to prevent hair loss from chemotherapy and radiotherapy. Cancer Res; 77(22); 6083-96. ©2017 AACR.


Assuntos
Alopecia/metabolismo , Proliferação de Células , Folículo Piloso/metabolismo , Células-Tronco/metabolismo , Alopecia/etiologia , Alopecia/fisiopatologia , Animais , Antineoplásicos Alquilantes/efeitos adversos , Ciclofosfamida/efeitos adversos , Feminino , Expressão Gênica , Folículo Piloso/citologia , Queratina-5/genética , Queratina-5/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Radiação Ionizante , Regeneração , Células-Tronco/citologia , Via de Sinalização Wnt/genética
12.
Arch Dermatol Res ; 308(1): 55-63, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26589685

RESUMO

Different studies have reported various values for the percentage of patients with IL36RN mutations, and it has also been reported that the sites of these mutations differ among different ethnicities. The current study was a cross-sectional study conducted to investigate the risk factors predicting IL36RN mutation in Chinese patients with different clinical features of pustular psoriasis. 57 Han Chinese patients, including 32 with generalized pustular psoriasis, 14 with palmoplantar pustulosis, 9 with plaque-type psoriasis with pustules, and 2 with erythrodermic psoriasis, were enrolled between March 2013 and July 2014. Blood samples were collected, genomic DNA was extracted from leukocytes, and polymerase chain reaction (PCR)-based Sanger sequencing was used to analyze the coding exons and flanking introns of the IL36RN gene. The patients with generalized pustular psoriasis exhibited the highest IL36RN mutation rate (75 %) among the aforementioned patient types, with the subgroup consisting of those patients who had features of acrodermatitis continua of Hallopeau exhibiting the highest c.115+6T>C mutation rate (93.8 %). In addition, early onset, ever generalized pustular psoriasis (more than two attacks), ever acrodermatitis continua of Hallopeau, inverse psoriasis, and a family history of pustular psoriasis were associated with IL36RN mutation. The c.115+6T>C mutation was the most common and the most important variant in all subtypes of pustular psoriasis with IL36RN mutations among our sample of Chinese patients.


Assuntos
Acrodermatite/genética , Acrodermatite/patologia , Interleucinas/genética , Psoríase/genética , Psoríase/patologia , Adolescente , Adulto , Povo Asiático/genética , Sequência de Bases , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco , Análise de Sequência de DNA , Taiwan , Adulto Jovem
15.
Tissue Eng Part C Methods ; 21(10): 1070-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25951188

RESUMO

Successful hair follicle (HF) neogenesis in adult life depends on the existence of both capable dermal cells and competent epidermal keratinocytes that recapitulate embryonic organogenesis through epithelial-mesenchymal interaction. In tissue engineering, the maintenance of trichogenic potential of adult epidermal cells, while expanding them remains a challenging issue. We found that although HF outer root sheath keratinocytes could be expanded for more than 100 passages as clonogenic cells without losing the proliferative potential with a 3T3J2 fibroblast feeder layer, these keratinocytes were unable to form new HFs when combined with inductive HF dermal papilla (DP) cells. However, when these high-passage keratinocytes were cocultured with HF DP cells for 4 days in vitro, they regained the trichogenic ability to form new HFs after transplantation. We found that the short-term coculture with DP cells enhanced both Wnt/ß-catenin signaling, a signaling cascade key to HF development, and upregulated the expression of HF-specific genes, including K6, K16, K17, and K75, in keratinocytes, indicating that these cells were poised toward a HF fate. Hence, efficient production of trichogenic keratinocytes can be obtained by a two-stepped procedure with initial cell expansion with a 3T3J2 fibroblast feeder followed by short-term coculture with DP cells.


Assuntos
Antígenos de Diferenciação/biossíntese , Técnicas de Cultura de Células/métodos , Regulação da Expressão Gênica , Folículo Piloso/metabolismo , Queratinócitos/metabolismo , Animais , Linhagem Celular , Células Alimentadoras/citologia , Células Alimentadoras/metabolismo , Feminino , Folículo Piloso/citologia , Queratinócitos/citologia , Queratinócitos/transplante , Ratos , Ratos Wistar
16.
ACS Appl Mater Interfaces ; 7(40): 22558-69, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-26402651

RESUMO

In the past decade, inorganic semiconductors have been successfully demonstrated as light absorbers in efficient solar water splitting to generate chemical fuels. Pseudobinary semiconductors Zn1-xCdxS (0≤x≤1) have exhibited a superior photocatalytic reactivity of H2 production from splitting of water by artificial solar irradiation without any metal catalysts. However, most studies had revealed that the extremely high efficiency with an optimal content of Zn1-xCdxS solid solution was determined as a result of elevating the conduction band minimum (CBM) and the width of bandgap. In addition to corresponding band structure and bandgap, the local crystal structure should be taken into account as well to determine its photocatalytic performance. Herein, we demonstrated the correlations between the photocatalytic activity and structural properties that were first studied through synchrotron X-ray diffraction and X-ray absorption spectroscopy. The crystal structure transformed from zinc blende to coexisted phases of major zinc blende and minor wurtzite phases at a critical point. The heterojunction formed by coexistence of zinc blende and wurtzite phases in the Zn1-xCdxS solid solution can significantly improve the separation and migration of photoinduced electron-hole pairs. Besides, X-ray absorption spectra and UV-vis spectra revealed that the bandgap of the Zn0.45Cd0.55S sample extended into the region of visible light because of the incorporation of Cd element in the sample. These results provided a significant progress toward the realization of the photoelectrochemical mechanism in heterojunction between zinc blende and wurtzite phases, which can effectively separate the charge-carriers and further suppress their recombination to enhance the photocatalytic reactivity.

20.
Biomaterials ; 34(2): 442-51, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23092862

RESUMO

Organ size and numbers are vital issues in bioengineering for hair follicle (HF) regeneration. Murine HF dermal papilla (DP) cells are able to induce HF neogenesis when transplanted as aggregates. However, how the preparation of murine and human DP aggregates affects HF inductivity and the size of regenerated HF is yet to be determined. Here we report a scalable method for production of controllable human and rat DP spheroids in general labs for reproducible experiments. Compared with more hydrophobic polyethylene and poly(ethylene-co-vinyl alcohol), DP cells are poorly adhesive to hydrophilic polyvinyl alcohol (PVA). Seeded in PVA-coated 96-welled commercial PCR tube arrays, DP cells quickly aggregate into single spheroids with progressive compaction. Varying seeded cell numbers and culture periods enables us to control the size and cell number of the spheroids. The spheroids obtained have high viability and preserve DP characters. A proof of principle experiment was conducted to examine the size effect on the efficiency and efficacy of HF regeneration. We found that both human and rat DP spheroids are able to induce HF neogenesis and larger DP spheroids exhibit higher HF inductivity. However, the average diameter of regenerated hair fiber did not significantly change with the increasing size of transplanted DP spheroids. The result suggests that an appropriate size of DP spheroid is essential for HF inductivity, but its size cannot be directly translated to a thicker regenerated hair. Our results also have implications on the efficiency and efficacy in the regeneration of other epithelial organs.


Assuntos
Folículo Piloso/citologia , Folículo Piloso/fisiologia , Regeneração , Esferoides Celulares/citologia , Engenharia Tecidual/métodos , Animais , Adesão Celular , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Álcool de Polivinil/química , Ratos , Ratos Wistar , Esferoides Celulares/transplante , Alicerces Teciduais/química
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