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1.
Cell Tissue Res ; 375(3): 723-731, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30392145

RESUMO

Cultured skin has been used extensively for testing therapeutic drugs because it replicates the physical and biochemical properties of whole skin. However, traditional static culture cannot fully maintain cell viability and skin morphology because of the limitations involved with nutrient transmission. Here, we develop a new dynamic perfusion platform for skin culture and compare it with a static culture device. Rat skins were cultured in either static or dynamic condition for 0, 3, 6, 9 and 12 days. H&E, periodic acid-Schiff (PAS) and picrosirius red (PSR) staining were used for skin morphology detection, immunostaining against cytokeratin 10 (CK10) for differentiation detection, immunostaining against proliferating cell nuclear antigen (PCNA) for cell proliferation detection and TUNEL staining for apoptosis detection. After culturing for 12 days, the epidermis, basement membrane, hair follicles and connective tissue were disrupted in the static group, whereas these features were preserved in the dynamic group. Moreover, compared to the static group, proliferation in the epidermis and hair follicles was significantly improved and apoptosis in dermis was significantly decreased in the dynamic group. These findings suggest that our device is effective for extending the culture period of rat skin to maintain its characteristics and viability in vitro.


Assuntos
Pele/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodos , Animais , Apoptose , Proliferação de Células , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Sprague-Dawley , Pele/anatomia & histologia , Pele/citologia , Coloração e Rotulagem
2.
Exp Dermatol ; 28(4): 395-405, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30537004

RESUMO

Skin evolves essential appendages and indispensable types of cells that synergistically insulate the body from environmental insults. Residing in the specific regions in the skin such as epidermis, dermis and hair follicle, melanocytes perform an array of vital functions including defending the ultraviolet radiation and diversifying animal appearance. As one of the adult stem cells, melanocyte stem cells in the hair follicle bulge niche can proliferate, differentiate and keep quiescence to control and coordinate tissue homeostasis, repair and regeneration. In synchrony with hair follicle stem cells, melanocyte stem cells in the hair follicles undergo cyclic activation, degeneration and resting phases, to pigment the hairs and to preserve the stem cells. Disorder of melanocytes results in severe skin problems such as canities, vitiligo and even melanoma. Here, we compare and summarize recent discoveries about melanocyte in the skin, particularly in the hair follicle. A better understanding of the physiological and pathological regulation of melanocyte and melanocyte stem cell behaviours will help to guide the clinical applications in regenerative medicine.


Assuntos
Células-Tronco Adultas/fisiologia , Melanócitos/fisiologia , Pigmentação da Pele , Animais , Plumas/metabolismo , Folículo Piloso/fisiologia , Humanos , Hipopigmentação/etiologia , Queratinócitos/fisiologia , Transdução de Sinais , Cicatrização
3.
Histochem Cell Biol ; 147(6): 749-758, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28185006

RESUMO

Regeneration of hair follicles relies on activation of hair follicle stem cells during telogen to anagen transition process in hair cycle. This process is rigorously controlled by intrinsic and environmental factors. 12-o-tetradecanoylphorbol-13-acetate (TPA), a tumor promoter, accelerates reentry of hair follicles into anagen phase. However, it is unclear that how TPA promotes the hair regeneration. In the present study, we topically applied TPA onto the dorsal skin of 2-month-old C57BL/6 female mice to examine the activity of hair follicle stem cells and alteration of signaling pathways during hair regeneration. We found that refractory telogen hair follicles entered anagen prematurely after TPA treatment, with the enhanced proliferation of CD34-positive hair follicle stem cells. Meanwhile, we observed Akt signaling was activated in epidermis, hair infundibulum, bulge and hair bulb, and Wnt signaling was also activated after hair follicle stem cells proliferation. Importantly, after overexpression of DKK1, a specific Wnt signaling inhibitor, the accelerated reentry of hair follicles into anagen induced by TPA was abolished. Our data indicated that TPA-induced hair follicle regeneration is associated with activation of Akt and Wnt/ß-catenin signaling.


Assuntos
Folículo Piloso/efeitos dos fármacos , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Regeneração/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Feminino , Cabelo/metabolismo , Folículo Piloso/citologia , Folículo Piloso/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteínas Wnt/metabolismo
4.
J Am Chem Soc ; 138(8): 2528-31, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26876042

RESUMO

Herein we present a new structural design of hole-transporting material, Trux-OMeTAD, which consists of a C3h Truxene-core with arylamine terminals and hexyl side-chains. This planar, rigid, and fully conjugated molecule exhibits excellent hole mobility and desired surface energy to the perovskite uplayer. Perovskite solar cells fabricated using the p-i-n architecture with Trux-OMeTAD as the p-layer, show a high PCE of 18.6% with minimal hysteresis.

5.
Cell Tissue Res ; 366(2): 329-340, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27464529

RESUMO

Melanocyte stem cells (McSCs) undergo cyclical activation and quiescence together with hair follicle stem cells (HFSCs). This process is strictly controlled by the autonomous and extrinsic signaling environment. However, the modulation of factors important for the activation of McSCs for hair pigmentation remains unclear. 12-O-tetradecanoylphorbol-13-acetate (TPA) mimics vital signaling pathways involved in melanocyte growth and melanogenesis in vitro. To investigate whether TPA regulates quiescent McSCs for hair pigmentation, we topically smeared TPA on 7-week-old mouse dorsal skin and found that TPA stimulated hair growth and hair matrix pigmentation. These changes were associated with a significant increase in the number of hair bulb melanocytes. Moreover, in the TPA-treated group, hair bulge McSCs and hair bulb melanoblasts actively proliferated. At the molecular level, nuclear ß-catenin, a key factor of Wnt/ß-catenin signaling, was highly synthesized in melanocytes and keratinocytes in TPA-induced hair bulbs. Inhibition of Wnt/ß-catenin signaling by injecting Dickkopf1 plasmids into TPA-treated skin decreased hair matrix pigmentation and inhibited the proliferation and differentiation of McSCs. Our findings suggest that the topical application of TPA stimulates the proliferation and differentiation of McSCs and their progeny for hair matrix pigmentation by activating Wnt/ß-catenin signaling. This might provide a useful experimental model for the study of signals controlling the activation of McSCs.


Assuntos
Folículo Piloso/citologia , Melanócitos/citologia , Melanócitos/metabolismo , Pigmentação/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Feminino , Folículo Piloso/crescimento & desenvolvimento , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Melanócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
6.
Cell Tissue Res ; 364(1): 149-58, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26553656

RESUMO

Hair follicles undergo cyclical growth and regression during postnatal life. Hair regression is an apoptosis-driven process strictly controlled by micro- and macro-environmental signals. However, how these signals are controlled remains largely unknown. Hoxc13, a member of the Hox gene family, is reported to play an important role in hair follicle differentiation. In the present study, we observed that Hoxc13 was highly expressed in the outer root sheath, matrix, medulla and inner root sheath of hair follicles in a hair cycle-dependent manner. We therefore investigated the role of Hoxc13 in hair follicle cycling. Injection of ShRNA (ShHoxc13) to suppress Hoxc13 in early anagen promoted premature catagen entry, shown by significantly decreased hair length and hair bulb size, increased percentage of catagen hair follicles, hair cycle score and TUNEL+ cells and inhibited proliferation. In contrast, local injection of recombinant Hoxc13 polypeptide (rhHoxc13) during the late anagen phase prolonged the anagen phase. Additionally, rhHoxc13 injections during the telogen phase significantly promoted hair growth and induced the anagen progression. At the molecular level, the expression of phosphorylated smad2 (p-smad2), a key factor of active TGF-ß1 signaling, was up-regulated in the ShHoxc13-treated hair follicles and down-regulated in rhHoxc13-treated hair follicles, suggesting that Hoxc13 might block anagen-catagen transition by inhibiting the TGF-ß1 signaling. Taken together, our data strongly suggest that Hoxc13 is a novel and crucial regulator of the hair cycle. This might also provide an understanding of the mechanism of the 'hair cycle clock' and the development of alopecia treatments.


Assuntos
Ciclo Celular/fisiologia , Folículo Piloso/metabolismo , Proteínas de Homeodomínio/metabolismo , Animais , Feminino , Folículo Piloso/citologia , Proteínas de Homeodomínio/genética , Camundongos , Proteína Smad2/genética , Proteína Smad2/metabolismo
7.
Histochem Cell Biol ; 144(3): 209-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25995040

RESUMO

Wnt10b is a signaling protein regulating skin development and homeostasis, and the expression of Wnt10b is restricted to epidermal keratinocytes in embryonic and postnatal skin. Recent studies indicate an elevated expression of Wnt10b in skin tumors. However, how Wnt10b regulates skin tumorigenesis remains largely unknown. Here we report that continuous expression of Wnt10b mediates transformation of epidermal keratinocytes through activating genes involved in EGF/MAPK signaling pathways. We first established a prolonged Wnt10b overexpression system in JB6P- cells to represent the elevated Wnt10b expression level in skin keratinocytes. Through expression assays and observations under phase-contrast microscopy, prolonged expression of Wnt10b activated Wnt/ß-catenin pathway and induced morphological changes of cells showing longer protrusions and multilayer growth, indicating early-stage cell transformation. Wnt10b also increased cellular proliferation and migration according to BrdU incorporation and cell mobility assays. Furthermore, multi-doses of AdWnt10b treatment to JB6P- cells induced colony formation, stronger invasive ability in transwell system, and anchorage-independent growth in agar gel. In molecular level, AdWnt10b treatment induced increased transcriptional expressions of Egf, downstream Mapk pathway factors, and MMPs. Administration of Wnt antagonist DKK1 blocked the tumor promotion process induced by Wnt10b. Taken together, these findings clearly demonstrate that Wnt10b promotes epidermal keratinocyte transformation through induced Egf pathway.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Fator de Crescimento Epidérmico/fisiologia , Epiderme/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Wnt/biossíntese , Antimetabólitos Antineoplásicos/farmacologia , Bromodesoxiuridina/farmacologia , Proliferação de Células , Células Epidérmicas , Epiderme/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Queratinócitos/patologia , Metaloproteinases da Matriz , Proteínas Quinases Ativadas por Mitógeno , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Ensaio Tumoral de Célula-Tronco , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/genética
8.
Cell Tissue Res ; 360(2): 333-46, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25727244

RESUMO

Hair follicle melanocyte stem cells (McSCs) are responsible for hair pigmentation and also function as a major melanocyte reservoir for epidermal pigmentation. However, the molecular mechanism promoting McSCs for epidermal pigmentation remains elusive. 12-O-tetradecanoylphorbol-13-acetate (TPA) mimics key signaling involved in melanocyte growth, migration and differentiation. We therefore investigated the molecular basis for the contribution of hair follicle McSCs to epidermal pigmentation using the TPA induction model. We found that repetitive TPA treatment of female C57BL/6 mouse dorsal skin induced epidermal pigmentation by increasing the number of epidermal melanocytes. Particularly, TPA treatment induced McSCs to initiate proliferation, exit the stem cell niche and differentiate. We also demonstrated that TPA promotes melanoblast migration and differentiation in vitro. At the molecular level, TPA treatment induced robust expression of stem cell factor (SCF) in keratinocytes and c-kit in melanoblasts and melanocytes. Administration of ACK2, a neutralizing antibody against the Kit receptor, suppressed mouse epidermal pigmentation, decreased the number of epidermal melanocytes, and inhibited melanoblast migration. Taken together, our data demonstrate that TPA promotes the expansion, migration and differentiation of hair follicle McSCs for mouse epidermal pigmentation. SCF/c-kit signaling was required for TPA-induced migration and differentiation of hair follicle melanocytes. Our findings may provide an excellent model to investigate the signaling mechanisms regulating epidermal pigmentation from mouse hair follicle McSCs, and a potential therapeutic option for skin pigmentation disorders.


Assuntos
Carcinógenos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Folículo Piloso/metabolismo , Melanócitos/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pigmentação da Pele/efeitos dos fármacos , Fator de Células-Tronco/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Animais , Feminino , Folículo Piloso/citologia , Camundongos
9.
Exp Dermatol ; 23(6): 407-13, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24750467

RESUMO

Hair follicles have characteristic sizes corresponding to their cycle-specific stage. However, how the anagen hair follicle specifies its size remains elusive. Here, we showed that in response to prolonged ectopic Wnt10b-mediated ß-catenin activation, regenerating anagen hair follicles grew larger in size. In particular, the hair bulb, dermal papilla and hair shaft became enlarged, while the formation of different hair types (Guard, Awl, Auchene and Zigzag) was unaffected. Interestingly, we found that the effect of exogenous WNT10b was mainly on Zigzag and less on the other kinds of hairs. We observed dramatically enhanced proliferation within the matrix, DP and hair shaft of the enlarged AdWnt10b-treated hair follicles compared with those of normal hair follicles at P98. Furthermore, expression of CD34, a specific hair stem cell marker, was increased in its number to the bulge region after AdWnt10b treatment. Ectopic expression of CD34 throughout the ORS region was also observed. Many CD34-positive hair stem cells were actively proliferating in AdWnt10b-induced hair follicles. Importantly, subsequent co-treatment with the Wnt inhibitor, DKK1, reduced hair follicle enlargement and decreased proliferation and ectopic localization of hair stem cells. Moreover, injection of DKK1 during early anagen significantly reduced the width of prospective hairs. Together, these findings strongly suggest that Wnt10b/DKK1 can modulate hair follicle size during hair regeneration.


Assuntos
Folículo Piloso/anatomia & histologia , Cabelo/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Regeneração/fisiologia , Proteínas Wnt/fisiologia , Animais , Antígenos CD34/fisiologia , Proliferação de Células/fisiologia , Feminino , Folículo Piloso/citologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Plasmídeos , Transdução de Sinais/fisiologia , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/genética , beta Catenina/fisiologia
10.
Int J Med Sci ; 11(10): 1022-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25076848

RESUMO

Sebaceous glands (SGs) undergo cyclic renewal independent of hair follicle stem cells (HFSCs) activation while HFSCs have the potential to differentiate into sebaceous gland cells, hair follicle and epidermal keratinocytes. Abnormalities of sebaceous gland progenitor cells contribute to the development of sebaceous neoplasms, but little is known about the role of HFSCs during sebaceous neoplasm development. Here, using dimethylbenzanthracene (DMBA) plus 12-o-tetradecanoyl phorbol-13-acetate (TPA) treatment developing sebaceous neoplasms (SNs) were identified with H&E and Oil red O staining. And then the molecular expression and activation of HFSCs and was characterized by immunostaining. Wnt10b/ß-catenin signaling molecular which is important for activation of HFSCs were detected by immunostaining. We found hair follicle and epidermal cell markers were expressed in sebaceous neoplasms. Furthermore, SOX-9 and CD34-positive HFSCs were located in the basal layer of sebaceous lobules within the sebaceous neoplasms. Many appear to be in an active state. Finally, Wnt10b/ß-catenin signaling was activated within the basal cells of sebaceous lobules in the sebaceous neoplasms. Collectively, our findings suggest that the abnormal activation of both HFSCs and Wnt10b/ß-catenin signaling involves in the development of sebaceous neoplasms.


Assuntos
Folículo Piloso/citologia , Neoplasias das Glândulas Sebáceas/metabolismo , Células-Tronco/metabolismo , beta Catenina/metabolismo , Animais , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Fatores de Transcrição SOX9/metabolismo , Neoplasias das Glândulas Sebáceas/genética , Células-Tronco/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia
11.
J Cosmet Dermatol ; 22(4): 1321-1326, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36575903

RESUMO

OBJECTIVE: The aim of the study was to investigate the efficacy and complications of ultra-minimal pinhole blepharoplasty in the treatment of eyelid bags. METHODS: This retrospective study included patients with eyelid bags treated using a minimally invasive blepharoplasty technique between May 2018 and June 2021. The postoperative course and complications and patient satisfaction were analyzed. RESULTS: A total of 460 patients (136 males and 324 females) were included with a mean age of 42.12 ± 9.76 years. The mean operative time was 24.3 min. After the operation, the patients had no infection, numbness, or lower eyelid varus, valgus, or withdrawal. Nine patients developed transient binocular diplopia, which disappeared 0.5-1 h after surgery. Two patients developed chemosis, which disappeared after therapy. Six months after the operation, 440 (95.65%) patients were satisfied with improvement in their fat bulge. A total of 434 (94.78%) patients were satisfied with improvement in their tear groove. CONCLUSION: Ultra-minimal pinhole blepharoplasty is a safe, effective, and minimally invasive treatment for eyelid bags.


Assuntos
Blefaroplastia , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Blefaroplastia/métodos , Estudos Retrospectivos , Pálpebras/cirurgia , Satisfação do Paciente
12.
ACS Appl Mater Interfaces ; 15(36): 42784-42791, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37647415

RESUMO

Photoluminescence (PL) measurements are a widely used technique for the investigation of perovskite-based materials and devices. Although electric field-induced PL quenching provides additional useful information, this phenomenon is quite complex and not yet clearly understood. Here, we address the PL quenching of methylammonium lead iodide (MAPbI3) perovskite in a light-emitting diode (PeLED) architecture. We distinguish two quenching mechanisms: (a) indirect quenching by slow irreversible or partially reversible material changes that occur gradually under the applied light and electric field and (b) direct quenching by the influence of the electric field on the charge carrier densities, their spatial distributions, and radiative recombination rates. Direct quenching, observed under the abrupt application of negative voltage, causes a decrease of the PL intensity. However, the PL intensity then partially recovers within tens of milliseconds as mobile ions screen the internal electric field. The screening time increases to hundreds of seconds at low temperatures, indicating activation energies for ion motion of about 80 meV. On the other hand, ultrafast time-resolved PL measurements revealed two main phases of direct quenching: an instantaneous reduction in the radiative carrier recombination rate, which we attribute to the electron and hole displacement within individual perovskite grains, followed by a second phase lasting hundreds of picoseconds, which is due to the charge carrier extraction and spatial separation of electron and hole "clouds" within the entire perovskite layer thickness.

13.
ACS Appl Mater Interfaces ; 15(5): 7294-7307, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36705637

RESUMO

Lead halide perovskites are promising candidates for high-performance light-emitting diodes (LEDs); however, their applicability is limited by their structural instability toward moisture. Although a deliberate addition of water to the precursor solution has recently been shown to improve the crystallinity and optical properties of perovskites, the corresponding thin films still do not exhibit a near-unity quantum yield. Herein, we report that the direct addition of a minute amount of water to post-treated formamidinium lead bromide (FAPbBr3) nanocrystals (NCs) substantially enhances the stability while achieving a 95% photoluminescence quantum yield in a NC thin film. We unveil the mechanism of how moisture assists in the formation of an additional NH4Br component. Alongside, we demonstrate the crucial role of moisture in assisting localized etching of the perovskite crystal, facilitating the partial incorporation of NH4+, which is key for improved performance under ambient conditions. Finally, as a proof-of-concept, the application of post-treated and water-treated perovskites is tested in LEDs, with the latter exhibiting a superior performance, offering opportunities toward commercial application in moisture-stable optoelectronics.

14.
Theranostics ; 13(9): 2930-2945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284452

RESUMO

Rationale: Stem cells self-organize to form organoids that generate mini-organs that resemble the physiologically-developed ones. The mechanism by which the stem cells acquire the initial potential for generating mini-organs remains elusive. Here we used skin organoids as an example to study how mechanical force drives initial epidermal-dermal interaction which potentiates skin organoids to regenerate hair follicles. Methods: Live imaging analysis, single-cell RNA-sequencing analysis, and immunofluorescence were used to analyze the contractile force of dermal cells in skin organoids. Bulk RNA-sequencing analysis, calcium probe detection, and functional perturbations were used to verify that calcium signaling pathways respond to the contractile force of dermal cells. In vitro mechanical loading experiment was used to prove that the stretching force triggers the epidermal Piezo1 expression which negatively regulates dermal cell attachment. Transplantation assay was used to test the regenerative ability of skin organoids. Results: We found that dermal cell-derived contraction force drives the movement of dermal cells surrounding the epidermal aggregates to trigger initial mesenchymal-epithelial interaction (MEI). In response to dermal cell contraction force, the arrangement of the dermal cytoskeleton was negatively regulated by the calcium signaling pathway which further influences dermal-epidermal attachment. The native contraction force generated from the dermal cell movement exerts a stretching force on the adjacent epidermal cells, activating the stretching force sensor Piezo1 in the epidermal basal cells during organoid culture. Epidermal Piezo1 in turn drives strong MEI to negatively regulate dermal cell attachment. Proper initial MEI by mechanical-chemical coupling during organoid culture is required for hair regeneration upon transplantation of the skin organoids into the back of the nude mice. Conclusion: Our study demonstrated that mechanical-chemical cascade drives the initial event of MEI during skin organoid development, which is fundamental to the organoid, developmental, and regenerative biology fields.


Assuntos
Folículo Piloso , Pele , Camundongos , Animais , Camundongos Nus , Organoides , RNA , Canais Iônicos
15.
Histochem Cell Biol ; 138(3): 385-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22585037

RESUMO

Gsdma3, a newly found gene, is expressed restrictedly in mouse skin keratinocytes and gastrointestinal tract. But until now, there is little information on the regulation and the function of Gsdma3 in skin keratinocytes. In our previous study, we found that Gsdma3 mutation resulted in a decrease in catagen-associated apoptosis of hair follicle keratinocytes. Apoptosis of skin keratinocytes is strictly regulated by a series of signal pathways, among of which, tumor necrosis factor (TNF)-α-induced signal pathway has been extensively studied. To further investigate the role and the pathway of Gsdma3 involved in skin keratinocyte apoptosis, using immunofluorescence, RT-PCR, western blot and TUNEL analysis, we showed here that accompanying TNF-α-induced apoptosis and Caspase-3 expression in mouse skin keratinocytes in vivo and in vitro, Gsdma3 expression was significantly upregulated. After Gsdma3 gene mutation, TNF-α-induced apoptosis and Caspase-3 expression in skin keratinocytes were reduced. The injection of Gsdma3 expression plasmid could directly enhance the apoptosis and Caspase-3 expression in skin keratinocytes. These results, taken together, indicated that in mouse skin keratinocytes, Gsdma3 expression could be regulated by TNF-α. Gsdma3 was not only involved in but also necessary for the TNF-α-induced apoptosis pathway by directly enhancing the Caspase3 expression as well as the apoptosis induction.


Assuntos
Apoptose , Queratinócitos/metabolismo , Proteínas/genética , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Animais , Caspase 3/metabolismo , Queratinócitos/enzimologia , Camundongos , Camundongos Endogâmicos , Pele/metabolismo , Regulação para Cima
16.
Phys Chem Chem Phys ; 14(35): 12094-8, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22868689

RESUMO

High-performance hybrid solar cells (HSCs) based on P3HT : CdSe QD blends are achieved through post-deposition ligand exchange by n-butanethiol (n-BT) with a high power conversion efficiency of 3.09%. The mechanism by which n-BT modifies the surface structures of CdSe QDs and thus improves the HSCs performance is investigated.

17.
ACS Appl Mater Interfaces ; 14(24): 27922-27931, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35687012

RESUMO

Volatile A-cation halide (AX) additives such as formamidinium chloride and methylammonium chloride have been widely employed for high-efficiency perovskite solar cells (PSCs). However, it remains unstudied how they influence the perovskite film stoichiometry and the solar cell performance and operational stability. Hereby, our work shows that over annealing of formamidinium chloride-containing perovskite films leads to a Pb-rich surface, resulting in a high initial efficiency, which however decays during maximum power point tracking (MPPT). On the contrary, perovskite films obtained by a shorter annealing time at the same temperature provide good stability during MPPT but a lower initial efficiency. Thus, we deduce that an optimal annealing is vital for both high efficiency and operational stability, which is then confirmed in the case where methylammonium chloride additive is used. With optimized perovskite annealing conditions, we demonstrate efficient and stable p-i-n PSCs that show a best power conversion efficiency of 20.7% and remain 90% of the initial performance after a 200 h MPPT at 60 °C under simulated 1 sun illumination with high UV content. Our work presents a comprehensive understanding on how volatile AX impacts perovskite film stoichiometry and its correlation to the device performance and operational stability, providing a new guideline for fabricating high-efficiency and operationally stable PSCs.

18.
ACS Appl Mater Interfaces ; 13(37): 44294-44301, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34498844

RESUMO

To guarantee a long lifetime of perovskite-based photovoltaics, the selected materials need to survive relatively high-temperature stress during the solar cell operation. Highly efficient n-i-p perovskite solar cells (PSCs) often degrade at high operational temperatures due to morphological instability of the hole transport material 2,2',7,7'-tetrakis (N,N-di-p-methoxyphenyl-amine)9,9'-spirobifluorene (Spiro-OMeTAD). We discovered that the detrimental large-domain spiro-OMeTAD crystallization is caused by the simultaneous presence of tert-butylpyridine (tBP) additive and gold (Au) as a capping layer. Based on this discovery and our understanding, we demonstrated facile strategies that successfully stabilize the amorphous phase of spiro-OMeTAD film. As a result, the thermal stability of n-i-p PSCs is largely improved. After the spiro-OMeTAD films in the PSCs were stressed for 1032 h at 85 °C in the dark in nitrogen environment, reference PSCs retained only 22% of their initial average power conversion efficiency (PCE), while the best target PSCs retained 85% relative average PCE. Our work suggests facile ways to realize efficient and thermally stable spiro-OMeTAD containing n-i-p PSCs.

19.
ACS Appl Mater Interfaces ; 13(14): 16766-16774, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33820414

RESUMO

Thin-film organic near-infrared (NIR) photodiodes can be essential building blocks in the rapidly emerging fields including the internet of things and wearable electronics. However, the demonstration of NIR organic photodiodes with not only high responsivity but also low dark current density that is comparable to that of inorganic photodiodes, for example, below 1 nA cm-2 for silicon photodiodes, remains a challenge. In this work, we have demonstrated non-fullerene acceptor-based NIR photodiodes with an ultralow dark current density of 0.2 nA cm-2 at -2 V by innovating on charge transport layers to mitigate the reverse charge injection and interfacial defect-induced current generation. The same device also shows a high external quantum efficiency approaching 70% at 850 nm and a specific detectivity of over 1013 Jones at wavelengths up to 940 nm. Furthermore, the versatility of our approach for mitigating dark current is demonstrated using a NIR photodetector utilizing different non-fullerene systems. Finally, the practical application of NIR organic photodiodes is demonstrated with an image sensor integrated on a silicon CMOS readout. This work provides new insight into the device stack design of low-dark current NIR organic photodiodes for weak light detection.

20.
ACS Appl Electron Mater ; 3(7): 3023-3033, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34337416

RESUMO

Following the rapid increase of organic metal halide perovskites toward commercial application in thin-film solar cells, inorganic alternatives attracted great interest with their potential of longer device lifetime due to the stability improvement under increased temperatures and moisture ingress. Among them, cesium lead iodide (CsPbI3) has gained significant attention due to similar electronic and optical properties to methylammonium lead iodide (MAPbI3), with a band gap of 1.7 eV, high absorption coefficient, and large diffusion length, while also offering the advantage of being completely inorganic, providing a higher thermal stability and preventing material degradation. On a device level, however, it seems also essential to replace organic transport layers by inorganic counterparts to further prevent degradation. In addition, devices are mostly fabricated by spin coating, limiting their reproducibility and scalability; in this case, exploring all-evaporated devices allows us to improve the quality of the layers and to increase their reproducibility. In this work, we focus on the deposition of CsPbI3 by CsI and PbI2 co-evaporation. We fabricate devices with an all-inorganic, all-evaporated structure, employing NiO and TiO2 as transport layers, and evaluate these devices for both photodetector and solar cell applications. As a photodetector, low leakage current, high external quantum efficiency (EQE) and detectivity, and fast rise and decay times were obtained, while as a solar cell, acceptable efficiencies were achieved. These all-inorganic, all-evaporated devices represent one step forward toward higher stability and reproducibility while enabling large area compatibility and easier integration with other circuitry and, in future, the possible commercialization of perovskite-based technology.

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