Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Nature ; 626(8001): 999-1004, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38418915

RESUMO

The advantage of 3D printing-that is, additive manufacturing (AM) of structural materials-has been severely compromised by their disappointing fatigue properties1,2. Commonly, poor fatigue properties appear to result from the presence of microvoids induced by current printing process procedures3,4. Accordingly, the question that we pose is whether the elimination of such microvoids can provide a feasible solution for marked enhancement of the fatigue resistance of void-free AM (Net-AM) alloys. Here we successfully rebuild an approximate void-free AM microstructure in Ti-6Al-4V titanium alloy by development of a Net-AM processing technique through an understanding of the asynchronism of phase transformation and grain growth. We identify the fatigue resistance of such AM microstructures and show that they lead to a high fatigue limit of around 1 GPa, exceeding the fatigue resistance of all AM and forged titanium alloys as well as that of other metallic materials. We confirm the high fatigue resistance of Net-AM microstructures and the potential advantages of AM processing in the production of structural components with maximum fatigue strength, which is beneficial for further application of AM technologies in engineering fields.

2.
Macromol Rapid Commun ; 44(5): e2200795, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36482873

RESUMO

Stretchable electrodes are highly demanded in various wearable and flexible electronic devices, whereas the efficient fabrication approach is still a challenge. In this work, an efficient shrinking method to fabricate carbon nanotube (CNT)-based stretchable electrodes is proposed. The electrode is a layer of anisotropic CNT wrinkling film coated on a latex balloon substrate (CNT@latex), whose resistivity remains stable after 25 000 stretching cycles of 0 to 50% tensile strain, and can survive up to 500% tensile train. The highly conductive electrode can be used as the current collector of a stretchable Zinc-ion battery, maintaining an output voltage of 1.3 V during the stretching process of 0 to 100%. The applications of the electrode in flexible triboelectric nanogenerators and Joule heating devices are also demonstrated, further indicating their good prospects in the field of stretchable electronic devices.


Assuntos
Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Látex , Eletrodos , Eletrônica
3.
Dermatol Ther ; 35(9): e15684, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35789520

RESUMO

We report a case of a 7-year-old male patient with vaccine-induced erythrodermic psoriasis (EP) complicated by pulmonary infection, hypoproteinemia, and liver dysfunction successfully treated with secukinumab in combination with symptomatic and supportive therapy. The patient presented with diffuse flushing on the head, face, trunk, and limbs, which were covered with chaff-like white scales in the rash-affected area, with no blisters, pustules, and no apparent abnormalities in the palms, soles, nails, and joints. Histopathology analysis revealed hyperkeratosis, focal parakeratosis, thinning or effacement of the granular layer, psoriasiform hyperplasia of the epidermis, neutrophilic microabscess formation in the upper part of the epidermis, edema of the dermal papilla, dilation of blood vessels, and lymphocyte infiltration. The patient was eventually diagnosed with EP. At weeks 0, 1, and 2, the patient received a subcutaneous injection of 150 mg secukinumab (three injections). Fluticasone propionate ointment, taccathitol ointment, yellow vaseline, and other drugs were also given topically. Following 2 weeks of treatment, the child's skin lesions resolved significantly with only slight pigmentation remaining and the Psoriasis Area and Severity Index (PASI) score decreased from 37.5 to 7.5 (PASI 75). Thereafter, 150 mg secukinumab was injected every 4 weeks until the last dose at 18 weeks (four more injections). After 18 weeks, the child's lesion resolved entirely (PASI 100), and no adverse effects were reported.


Assuntos
Psoríase , Vacinas , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Criança , Método Duplo-Cego , Humanos , Injeções Subcutâneas , Masculino , Pomadas/uso terapêutico , Psoríase/diagnóstico , Psoríase/tratamento farmacológico , Psoríase/patologia , Índice de Gravidade de Doença , Resultado do Tratamento
4.
J Dermatolog Treat ; 35(1): 2309305, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38297481

RESUMO

Background: Psoriatic patients tend to develop metabolic syndrome (MS). MS accelerates psoriasis, but the exact molecular mechanisms are poorly understood.Objectives: We aim to investigate the impact of leptin on keratinocyte insulin sensitivity and explore its underlying molecular mechanism, which might play a role in the pathogenesis of this disease.Methods: ELISA and immunohistochemistry were applied respectively to detect the level of leptin in serum and in lesion of psoriatic patients with and without MS. The HaCaT cell line was cultured and western-blot assay was performed to assess the change of insulin sensibility. q-PCR and western-blot assay were applied to detect the SOCS3 expressions. Knockdown of SOCS3 were generated in HaCaT cell line by siRNA. Leptin and insulin were treated for 6 days and K10 expression was evaluated by western-blot assay.Results: Patients with MS had higher level of leptin in serum and lesions than their counterparts without MS. Serum levels of leptin was negatively correlated to PASI decline index in psoriatic patients. Long-term treatment of leptin induced insulin resistance in HaCaT cell line, as indicated by elevated expression of p-IRS-1 (ser636) and lower p-PKB (ser473). Leptin treatment up-regulated the mRNA and protein expression of SOCS3. Knockdown of SOCS3 blocked the effect of leptin-induced insulin resistance. Leptin treatment attenuated insulin-elicited K10 expression.Conclusions: Leptin induces insulin resistance by upregulating SOCS3 and give rise to differentiation disorder of keratinocyte. Insulin resistance may serve as a target for anti-psoriatic therapies.


Assuntos
Resistência à Insulina , Insulinas , Síndrome Metabólica , Psoríase , Humanos , Leptina , Psoríase/induzido quimicamente , Queratinócitos , Insulinas/efeitos adversos , Insulinas/metabolismo
5.
Balkan Med J ; 41(3): 174-185, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700313

RESUMO

Background: Psoriasis is a chronic inflammatory skin disease that has no cure. While the specific cause of psoriasis is unknown, interactions between immune cells and inflammatory cytokines are believed to be important in its pathogenesis. Thymic stromal lymphopoietin (TSLP) is a cytokine produced by epithelial cells that profoundly affects dendritic cells (DCs) and is involved in allergy and inflammatory diseases. In some studies, its expression is higher in the skin of psoriasis patients, whereas it is increased in treated psoriasis patients when compared with untreated patients in others. Aims: To investigate the role of TSLP in the pathogenesis of psoriasis. Study Design: In vitro and in vivo study. Methods: To investigate the effect of TSLP on psoriasis in vivo, a mouse psoriasis model and shRNA targeting TSLP to reduce its expression were used. Mouse primary bone marrow dendritic cells (BMDCs) were cultured in vitro and used to investigate the signaling pathways activated by TSLP. Results: We found that reducing TSLP expression in psoriasis skin alleviated disease severity. TSLP activated the Janus kinase (JAK)/SYK pathway in psoriatic skin. In vitro studies with BMDCs demonstrated that TSLP increased DC maturation through the JAK/SYK pathway and activated DCs-secreted cytokines that stimulated CD4+ T cells to develop into T helper 17 (Th17) cells by activating STAT3 signaling. The JAK/SYK pathway inhibitor reduced the effect of TSLP on activating BMDCs and promoting Th17 differentiation by CD4+ T cells. Conclusion: These findings indicated that TSLP exerted its immune-modulating effect in psoriasis through the JAK/SYK pathway.


Assuntos
Citocinas , Células Dendríticas , Psoríase , Células Th17 , Linfopoietina do Estroma do Timo , Animais , Humanos , Camundongos , Citocinas/metabolismo , Citocinas/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Modelos Animais de Doenças , Janus Quinases , Transdução de Sinais/efeitos dos fármacos , Quinase Syk , Células Th17/efeitos dos fármacos , Células Th17/imunologia
6.
Clin Cosmet Investig Dermatol ; 16: 2297-2307, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37641663

RESUMO

Purpose: The underlying pathophysiology linking psoriasis vulgaris (PV) and metabolic syndrome (MetS) is not fully understood. The present study aimed to investigate the serum level of interleukin (IL)-9 and tissue levels of IL-9 and its receptor in PV patients with MetS and analyze the correlation of IL-9 levels with psoriasis disease severity and MetS. Methods: This study enrolled 75 PV patients with MetS, 57 PV patients without MetS, 20 healthy blood donors, and 7 healthy skin donors. Clinical, socio-demographic, and anthropometric data were obtained from all individuals. Fasting blood glucose, insulin, lipid profile levels, and serum levels of IL-9 and IL-17A were measured. The expression of IL-9 and its receptor in skin specimens in PV patients and healthy controls was determined using immunohistochemistry. Normal human epidermal keratinocytes were stimulated with five pro-inflammatory cytokines (tumor necrosis factor-α, oncostatin M, IL-22, IL-17A, and IL-1α) to establish a psoriatic keratinocyte model and subsequently treated with IL-9. Their mRNA levels of antimicrobial peptides and chemokines were measured using quantitative real-time polymerase chain reaction. Results: Serum level of IL-9 and tissue levels of IL-9 and its receptor were upregulated in PV patients with MetS. IL-9 level was positively correlated to IL-17A level; however, no significant correlation of IL-9 level with psoriasis area severity index was observed. IL-9 level had a positive correlation with the presence of MetS and its components. Correspondingly, IL-9 level positively correlated with waist circumference, body mass index, homeostasis model assessment-insulin resistance, blood pressure, and triglyceride level and negatively correlated with high-density lipoprotein cholesterol level. Additionally, IL-9 stimulated the expression of antimicrobial peptides and chemokines in a psoriatic keratinocyte model. Conclusion: Our findings confirmed that higher IL-9 level is associated with PV complicated by MetS, suggesting that IL-9 may be a link between PV and MetS.

7.
Polymers (Basel) ; 14(14)2022 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-35890576

RESUMO

Flexible, stretchable, wearable, and stable electronic materials are widely studied, owing to their applications in wearable devices and the Internet of Things. Because of the demands for both strain-insensitive resistors and high gauge factor (GF) strain-sensitive materials, anisotropic strain sensitivity has been an important aspect of electronic materials. In addition, the materials should have adjustable strain sensitivities. In this work, such properties are demonstrated in reduced graphene oxide (RGO) with hierarchical oriented wrinkle microstructures, generated using the two-step shrinkage of a rubber substrate. The GF values range from 0.15 to 28.32 at 100% strain. For device demonstrations, macrostructure patterns are designed to prepare patterned wrinkling graphene at rubber substrate (PWG@R). Serpentiform curves can be used for the constant-value resistor, combined with the first-grade wrinkles. Strip lines can increase the strain-sensing property, along with the second-grade wrinkles. The patterned sensor exhibits improved GF values range from 0.05 to 49.5. The assembled sensor shows an excellent stability (>99% retention after 600 cycles) with a high GF (49.5). It can monitor the vital signs of the throat and wrist and sense large motions of fingers. Thus, PWG@R-based strain sensors have great potential in various health or motion monitoring fields.

8.
World J Clin Cases ; 10(18): 5965-5983, 2022 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-35949853

RESUMO

BACKGROUND: Psoriasis is a chronic inflammatory skin disease, the pathogenesis of which is more complicated and often requires long-term treatment. In particular, moderate to severe psoriasis usually requires systemic treatment. Psoriasis is also associated with many diseases, such as cardiometabolic diseases, malignant tumors, infections, and mood disorders. Psoriasis can appear at any age, and lead to a substantial burden for individuals and society. At present, psoriasis is still a treatable, but incurable, disease. Previous studies have found that microRNAs (miRNAs) play an important regulatory role in the progression of various diseases. Currently, miRNAs studies in psoriasis and dermatology are relatively new. Therefore, the identification of key miRNAs in psoriasis is helpful to elucidate the molecular mechanism of psoriasis. AIM: To identify key molecular markers and signaling pathways to provide potential basis for the treatment and management of psoriasis. METHODS: The miRNA and mRNA data were obtained from the Gene Expression Omnibus database. Then, differentially expressed mRNAs (DEmRNAs) and differentially expressed miRNAs (DEmiRNAs) were screened out by limma R package. Subsequently, DEmRNAs were analyzed for Gene Ontology and Kyoto Encyclopedia of Genes and Genomics functional enrichment. The "WGCNA" R package was used to analyze the co-expression network of all miRNAs. In addition, we constructed miRNA-mRNA regulatory networks based on identified hub miRNAs. Finally, in vitro validation was performed. All experimental procedures were approved by the ethics committee of Chinese PLA General Hospital (S2021-012-01). RESULTS: A total of 639 DEmRNAs and 84 DEmiRNAs were identified. DEmRNAs screening criteria were adjusted P (adj. P) value < 0.01 and |logFoldChange| (|logFC|) > 1. DEmiRNAs screening criteria were adj. P value < 0.01 and |logFC| > 1.5. KEGG functional analysis demonstrated that DEmRNAs were significantly enriched in immune-related biological functions, for example, toll-like receptor signaling pathway, cytokine-cytokine receptor interaction, and chemokine signaling pathway. In weighted gene co-expression network analysis, turquoise module was the hub module. Moreover, 10 hub miRNAs were identified. Among these 10 hub miRNAs, only 8 hub miRNAs predicted the corresponding target mRNAs. 97 negatively regulated miRNA-mRNA pairs were involved in the miRNA-mRNA regulatory network, for example, hsa-miR-21-5p-claudin 8 (CLDN8), hsa-miR-30a-3p-interleukin-1B (IL-1B), and hsa-miR-181a-5p/hsa-miR-30c-2-3p-C-X-C motif chemokine ligand 9 (CXCL9). Real-time polymerase chain reaction results showed that IL-1B and CXCL9 were up-regulated and CLDN8 was down-regulated in psoriasis with statistically significant differences. CONCLUSION: The identification of potential key molecular markers and signaling pathways provides potential research directions for further understanding the molecular mechanisms of psoriasis. This may also provide new research ideas for the prevention and treatment of psoriasis in the future.

9.
Physiol Behav ; 229: 113223, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127465

RESUMO

In recent years, due to its rapid reproduction rate and the similarity of its genetic structure to that of human, the zebrafish has been widely used as a pain model to study chemical influences on behavior. Swimming behaviors are mediated by motoneurons in the spinal cord that drive muscle contractions, therefore a knowledge of internal muscle mechanics can assist the understanding of the effects of drugs on swimming activity. To demonstrate that the technique used in our study can supplement biological observations by quantifying the contribution of muscle effects to altered swimming behaviours, we have evaluated the pain/damage caused by 0.1% acetic acid to the muscle of 5 dpf zebrafish larvae and the effect of protection from this pain/damage with the saponin Gypenosides (GYP) extracted from Gynostemma pentaphyllum. We have quantified the parameters related to muscle such as muscle power and the resultant hydrodynamic force, proving that GYP could alleviate the detrimental effect of acetic acid on zebrafish larvae, in the form of alleviation from swimming debility, and that the muscle status could be quantified to represent the degree of muscle damage due to the acetic acid and the recovery due to GYP. We have also linked the behavioral changes to alteration of antioxidant and inflammation gene expression. The above results provide novel insights into the reasons for pain-related behavioral changes in fish larvae, especially from an internal muscle perspective, and have quantified these changes to help understand the protection of swimming behaviors and internal muscle by GYP from acetic acid-induced damage.


Assuntos
Gynostemma , Peixe-Zebra , Animais , Humanos , Hidrodinâmica , Dor/tratamento farmacológico , Extratos Vegetais , Natação
10.
PeerJ ; 8: e8374, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31938582

RESUMO

The use of zebrafish larvae has aroused wide interest in the medical field for its potential role in the development of new therapies. The larvae grow extremely quickly and the embryos are nearly transparent which allows easy examination of its internal structures using fluorescent imaging techniques. Medical treatment of zebrafish larvae can directly influence its swimming behaviours. These behaviour changes are related to functional changes of central nervous system and transformations of the zebrafish body such as muscle mechanical power and force variation, which cannot be measured directly by pure experiment observation. To quantify the influence of drugs on zebrafish larvae swimming behaviours and energetics, we have developed a novel methodology to exploit intravital changes based on observed zebrafish locomotion. Specifically, by using an in-house MATLAB code to process the recorded live zebrafish swimming video, the kinematic locomotion equation of a 3D zebrafish larvae was obtained, and a customised Computational Fluid Dynamics tool was used to solve the fluid flow around the fish model which was geometrically the same as experimentally tested zebrafish. The developed methodology was firstly verified against experiment, and further applied to quantify the fish internal body force, torque and power consumption associated with a group of normal zebrafish larvae vs. those immersed in acetic acid and two neuroactive drugs. As indicated by our results, zebrafish larvae immersed in 0.01% acetic acid display approximately 30% higher hydrodynamic power and 10% higher cost of transport than control group. In addition, 500 µM diphenylhydantoin significantly decreases the locomotion activity for approximately 50% lower hydrodynamic power, whereas 100 mg/L yohimbine has not caused any significant influences on 5 dpf zebrafish larvae locomotion. The approach has potential to evaluate the influence of drugs on the aquatic animal's behaviour changes and thus support the development of new analgesic and neuroactive drugs.

12.
Artigo em Inglês | MEDLINE | ID: mdl-28111251

RESUMO

The zebrafish has become a commonly used vertebrate model for toxicity assessment, of particular relevance to the study of toxic effects on the visual system because of the structural similarities shared by zebrafish and human retinae. In this article we present a colour preference-based technique that, by assessing the functionality of photoreceptors, can be used to evaluate the effects of toxicity on behaviour. A digital camera was used to record the locomotor behaviour of individual zebrafish swimming in a water tank consisting of two compartments separated by an opaque perforated wall through which the fish could pass. The colour of the lighting in each compartment could be altered independently (producing distinct but connected environments of white, red or blue) to allow association of the zebrafish's swimming behaviour with its colour preference. The functionality of the photoreceptors was evaluated based on the ability of the zebrafish to sense the different colours and to swim between the compartments. The zebrafish tracking was carried out using our algorithm developed with MATLAB. We found that zebrafish preferred blue illumination to white, and white illumination to red. Acute treatment with acrylamide (2mM for 36h) resulted in a marked reduction in locomotion and a concomitant loss of colour-preferential swimming behaviour. Histopathological examination of acrylamide-treated zebrafish eyes showed that acrylamide exposure had caused retinal damage. The colour preference tracking technique has applications in the assessment of neurodegenerative disorders, as a method for preclinical appraisal of drug efficacy and for behavioural evaluation of toxicity.


Assuntos
Acrilamida/toxicidade , Comportamento Animal/efeitos dos fármacos , Visão de Cores/efeitos dos fármacos , Retina/efeitos dos fármacos , Testes de Toxicidade Aguda/métodos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/fisiologia , Actigrafia , Algoritmos , Animais , Feminino , Processamento de Imagem Assistida por Computador , Luz , Masculino , Microscopia Confocal , Concentração Osmolar , Células Fotorreceptoras de Vertebrados/citologia , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/fisiologia , Células Fotorreceptoras de Vertebrados/efeitos da radiação , Projetos Piloto , Retina/citologia , Retina/fisiologia , Retina/efeitos da radiação , Neurônios Retinianos/citologia , Neurônios Retinianos/efeitos dos fármacos , Neurônios Retinianos/fisiologia , Neurônios Retinianos/efeitos da radiação , Peixe-Zebra/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA