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1.
Animals (Basel) ; 13(9)2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37174568

RESUMO

Cyclospora spp. is a food-borne intestinal protozoan, which is widely distributed in the world and poses the risk of zoonosis. In order to reveal the prevalence of Cyclospora spp. in Holstein cattle in partial areas of the Yunnan Province, 524 fresh fecal samples of Holstein cattle were collected from Dali, Kunming, Chuxiong, and Qujing in Yunnan Province. A nested PCR amplification of the small subunit (SSU) rRNA gene of Cyclospora spp. was carried out, and the products of the nested PCR were further analyzed by restriction fragment length polymorphism (RFLP) using Bsp E Ⅰ. The results of the present study showed that 13 samples were positive for Cyclospora spp., and the total infection rate of Cyclospora sp. was 2.48%. The infection of Cyclospora spp. was detected in Dali, Qujing, and Chuxiong. Chuxiong showed the highest infection rate (5.71%), and infection rate in Dali and Qujing was 2.19% and 3.16%, respectively. Interestingly, the infection of Cyclospora spp. was not detected in Kunming. The infection of Cyclospora spp. showed no significant differences among different regions (p > 0.05). Cyclospora sp. infection was detected in all ages and sexes, but the differences were not significant (p > 0.05). Sequencing and phylogenetic analysis showed that five Cyclospora spp. samples were closely related to the Cyclospora spp. of humans, and the others were closely related to the Cyclospora spp. of bovines. The results of the present study suggested that there was an infection of Cyclospora spp. in Holstein cattle in the Yunnan Province, and the Cyclospora spp. showed a risk of zoonosis. Thus, the prevention and control of Cyclospora spp. should be strengthened in the Yunnan Province, China. The results of this investigation provide data references for the further research of Cyclosporiasis in Holstein cattle in the Yunnan Province.

2.
J Cosmet Dermatol ; 21(2): 564-570, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34971470

RESUMO

OBJECTIVES: Tear trough deformity (TTD) is becoming a growing concern for those seeking facial rejuvenation, and various treatment strategies have been reported. Among treatment options is micro-autologous fat injection, which appears to be an effective approach to recontour the tear trough in the young. The study we present here investigated the reliability and effectiveness of two-dimensional fat injections (TDFI) in the treatment of young patients with TTD. METHODS: This study evaluated patients with TTD who underwent TDFI between December 2018 and December 2020. The proposed procedure involved ligament releasing and fat injection into the tear trough in two different directions. RESULTS: The average age of the 102 enrolled patients was 25.9 ± 3.8 years. Significant improvement and maintenance of TTD were observed during the follow-up period (13.2 months average) with no major complications being observed. Improvement of dark cycles and enhanced aegyo sal were observed. Patient satisfaction based upon self-administered post-procedure questionnaires disclosed that 58.8% were very satisfied, 38.2% were satisfied, and 2.9% neutral with the results. CONCLUSIONS: Two-dimensional fat injections is an effective and reliable method with high satisfaction and low risk of complication. Long-term results demonstrated its utility for young-type TTD.


Assuntos
Blefaroplastia , Pálpebras , Tecido Adiposo/transplante , Adulto , Pálpebras/cirurgia , Humanos , Rejuvenescimento , Reprodutibilidade dos Testes , Adulto Jovem
3.
Micromachines (Basel) ; 12(11)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34832731

RESUMO

A polycrystalline diamond (PCD) tool is employed in cutting various titanium alloys because of its excellent properties. However, improving the cutting performance of titanium alloys is still a challenge. Here, an experimental investigation on the influence of ultrasonic vibration-assisted machining (UVAM) of Ti6Al4V titanium alloy on the cutting performance and action mechanism was studied using a PCD tool. Cutting force, machined surface, surface adhesion, and wear morphology were analyzed. The results indicated that UVAM can effectively improve cutting performance. It was found that there was serious adhesion and wear of slight fragments close to the cutting edge after ultrasonic-assisted dry milling. Furthermore, the action mechanism of UVAM in improving cutting performance was discussed and analyzed from the perspective of intermittent cutting.

4.
Exp Mol Pathol ; 115: 104468, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32445750

RESUMO

OBJECTIVE: Exosomes originated from mesenchymal stem cells (MSCs) benefit wound healing. This study investigated effects of exosomes originated from human umbilical cord MSCs (hUC-MSCs) on dermal fibroblasts-myofibroblasts transition via the TGF-ß1/Smad2/3 signaling pathway. METHODS: Firstly, hUC-MSCs were collected and identified. Alizarin red, oil red O staining and toluidine blue staining were used to determine the osteogenic, adipogenic and chondrogenic differentiation abilities of hUC-MSCs. Then exosomes from hUC-MSCs were extracted and identified. To figure out the roles of exosomes and TGF-ß1 in dermal fibroblasts-myofibroblasts transition, dermal fibroblasts were treated with TGF-ß1 or/and exosomes at different concentrations. RT-qPCR, Western blot analyses were employed to examine levels of Collagen I, Collagen III, α-smooth muscle actin (α-SMA), and Smad2/3 phosphorylation, and immunofluorescence was employed to test α-SMA content and the localization and nucleation of Smad2/3 protein in cells. RESULTS: hUC-MSCs and exosomes were successfully cultured and extracted. Levels of Collagen I, Collagen III, α-SMA, and Smad2/3, and Smad2/3 phosphorylation in fibroblasts treated with exosomes decreased markedly. After treatment with exosomes and TGF-ß1 together, levels of Collagen I, Collagen III, α-SMA, and Smad2/3, and Smad2/3 phosphorylation in fibroblasts decreased significantly as compared to TGF-ß1-treated fibroblasts. Exosome treatment reduced the entry of Smad2/3 into fibroblasts. CONCLUSION: Our data suggested that hUC-MSCs-derived exosomes could inhibit dermal fibroblasts-myofibroblasts transition by inhibiting the TGF-ß1/Smad2/3 signaling pathway.


Assuntos
Exossomos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Miofibroblastos/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Cordão Umbilical/citologia , Células Cultivadas , Derme/citologia , Exossomos/ultraestrutura , Humanos , Recém-Nascido
5.
Drug Des Devel Ther ; 11: 659-668, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28293102

RESUMO

Malignant melanoma (MM) is the most dangerous type of skin cancer with annually increasing incidence and death rates. However, chemotherapy for MM is restricted by low topical drug concentration and multidrug resistance. In order to surmount the limitation and to enhance the therapeutic effect on MM, a new nanoformulation of paclitaxel (PTX)-loaded cholic acid (CA)-functionalized star-shaped poly(lactide-co-glycolide) (PLGA)-D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles (NPs) (shortly PTX-loaded CA-PLGA-TPGS NPs) was fabricated by a modified method of nanoprecipitation. The particle size, zeta potential, morphology, drug release profile, drug encapsulation efficiency, and loading content of PTX-loaded NPs were detected. As shown by confocal laser scanning, NPs loaded with coumarin-6 were internalized by human melanoma cell line A875. The cellular uptake efficiency of CA-PLGA-TPGS NPs was higher than those of PLGA NPs and PLGA-TPGS NPs. The antitumor effects of PTX-loaded NPs were evaluated by the MTT assay in vitro and by a xenograft tumor model in vivo, demonstrating that star-shaped PTX-loaded CA-PLGA-TPGS NPs were significantly superior to commercial PTX formulation Taxol®. Such drug delivery nanocarriers are potentially applicable to the improvement of clinical MM therapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Portadores de Fármacos/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Melanoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Paclitaxel/farmacologia , Polímeros/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Portadores de Fármacos/administração & dosagem , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Melanoma/patologia , Nanopartículas/química , Paclitaxel/administração & dosagem , Tamanho da Partícula , Polímeros/química , Relação Estrutura-Atividade , Propriedades de Superfície , Células Tumorais Cultivadas
6.
ACS Appl Mater Interfaces ; 8(9): 5906-16, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26886167

RESUMO

Human dermal papilla (DP) cells have been studied extensively when grown in the conventional monolayer. However, because of great deviation from the real in vivo three-dimensional (3D) environment, these two-dimensional (2D) grown cells tend to lose the hair-inducible capability during passaging. Hence, these 2D caused concerns have motivated the development of novel 3D culture techniques to produce cellular microtissues with suitable mimics. The hanging-drop approach is based on surface tension-based technique and the interaction between surface tension and gravity field that makes a convergence of liquid drops. This study used this technique in a converged drop to form cellular spheroids of dermal papilla cells. It leads to a controllable 3Dspheroid model for scalable fabrication of inductive DP microtissues. The optimal conditions for culturing high-passaged (P8) DP spheroids were determined first. Then, the morphological, histological and functional studies were performed. In addition, expressions of hair-inductive markers including alkaline phosphatase, α-smooth muscle actin and neural cell adhesion molecule were also analyzed by quantitative RT-PCR, immunostaining and immunoblotting. Finally, P8-DP microtissues were coimplanted with newborn mouse epidermal cells (EPCs) into nude mice. Our results indicated that the formation of 3D microtissues not only endowed P8-DP microtissues many similarities to primary DP, but also confer these microtissues an enhanced ability to induce hair-follicle (HF) neogenesis in vivo. This model provides a potential to elucidate the native biology of human DP, and also shows the promising for the controllable and scalable production of inductive DP cells applied in future follicle regeneration.


Assuntos
Derme/citologia , Folículo Piloso/fisiologia , Regeneração/fisiologia , Animais , Técnicas de Cultura de Células , Células Cultivadas , Derme/metabolismo , Folículo Piloso/patologia , Humanos , Immunoblotting , Camundongos , Camundongos Nus , Microscopia de Fluorescência , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Esferoides Celulares/citologia , Esferoides Celulares/metabolismo , Tensão Superficial
7.
Acta Histochem ; 117(8): 798-802, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26257011

RESUMO

Lysozyme is a well-known antimicrobial peptide that exists widely in mammalian skin and it is also expressed by pilosebaceous units. However, the exact location of lysozyme in hair follicles and whether it exerts any direct effects on hair follicle growth are unclear. To determine whether lysozyme affected hair growth in vitro, micro-dissected mouse vibrissae follicles (VFs) were treated in serum-free organ culture for 3 days with lysozyme (1-10µg/ml). After that, the effects of lysozyme on dermal papilla (DP) cells were also investigated. Lysozyme was mainly identified in DP and dermal sheath regions of VF by immunochemistry. In addition, 5-10µg/ml lysozyme had a promoting effect on shaft production. It was also associated with significant proliferation of matrix keratinocytes by immunofluorescence observation. Furthermore, lysozyme promoted hair growth by increasing the levels of alkaline phosphatase and lymphoid enhancer factor 1 in DP, as determined by Western blotting. These results indicate that lysozyme is a promoter of VF growth via enhancing the hair-inductive capacity of DP cells during organ culture.


Assuntos
Folículo Piloso/enzimologia , Muramidase/fisiologia , Vibrissas/enzimologia , Animais , Feminino , Folículo Piloso/citologia , Folículo Piloso/crescimento & desenvolvimento , Camundongos Endogâmicos C57BL , Muramidase/farmacologia , Técnicas de Cultura de Tecidos , Vibrissas/crescimento & desenvolvimento
8.
Chemistry ; 17(8): 2435-41, 2011 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-21319237

RESUMO

Self-complementary monomer 1, which combines a macrotricyclic polyether and two dibenzylammonium ions together, was synthesized, and its self-assembly into supramolecular polymer networks by host-guest interactions was studied. For the purpose of comparative study, two model molecules 2 and 3 were also prepared. It was found that model molecule 2 and dibenzylammonium ion 4 form a 1:2 complex in solution and in the solid state, which afforded a model system for the investigation of the assembly behavior of monomer 1. Consequently, the (1)H NMR spectrum of 1 in CD(3)CN showed characteristic proton signals similar to the model system, which suggested that 1 self-assembles into a supramolecular polymer network. Formation of the supramolecular polymer was further evidenced by the MALDI-TOF MS spectrum, viscometry, and dynamic light-scattering (DLS) experiments. Moreover, it was found that the decomposition and re-formation of the supramolecular polymer could be chemically controlled by the use of triethylamine and trifluoroacetic acid. Interestingly, the supramolecular polymer forms an organogel both in CD(3)CN and in 1:1 (v/v) CDCl(3)/CD(3)CN, and reversible thermo- and pH-induced gel-sol transitions were also found. The presented work will provide a new strategy for the construction of supramolecular polymers with specific structures and properties.

9.
Chemistry ; 16(28): 8537-44, 2010 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-20540052

RESUMO

On the basis of formation of [2]pseudorotaxane complexes between triptycene-derived tetralactam macrocycles 1a and 1b and squaraine dyes, construction of squaraine-based [2]rotaxanes through clipping reactions were studied in detail. As a result, when two symmetrical squaraines 2d and 2e were utilized as templates, two pairs of isomeric [2]rotaxanes 3a-b and 4a-b as diastereomers were obtained, owing to the two possible linking modes of triptycene derivatives. It was also found, interestingly, that when a nonsymmetrical dye 2g was involved, there existed simultaneously three isomers of [2]rotaxanes in one reaction due to the different directions of the guest threading. The (1)H NMR and 2D NOESY NMR spectra were used to distinguish the isomers, and the yield of [2]rotaxane 5a with the benzyl group in the wider rim of the host 1a was found to be higher than that of another isomer 5b with an opposite direction of the guest, which indicated the partial selection of the threading direction. The X-ray structures of 3b and 4a showed that, except for the standard hydrogen bonds between the amide protons of the hosts and the carbonyl oxygen atoms of the guests, multiple pi...pi stacking and C-H...pi interactions between triptycene subunits and aromatic rings of the guests also participated in the complexation. Crystallographic studies also revealed that the [2]rotaxane molecules 3b and 4a further self-assembled into tubular structures in the solid state with the squaraine dyes inside the channels. In the case of 4a, all the nonsymmetrical macrocyclic molecules pointed in one direction, which suggests the formation of oriented tubular structures. Moreover, it was also found that the squaraines encapsulated in the triptycene-derived macrocycles were protected from chemical attack, and subsequently have potential applications in imaging probes and other biomedical areas.

10.
Org Lett ; 12(8): 1888-91, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20337447

RESUMO

A novel anthracene-based cylindrical macrotricyclic polyether containing two dibenzo-30-crown-10 cavities has been synthesized and shown to be a powerful host to form 1:1 stable complexes with the rodlike bispyridinium dications (K(a) > 10(5) M(-1)). Moreover, it was found that the complexes could all self-assemble into linear supramolecular arrays and further 2D mosaic-like architectures in the solid state.

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