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1.
Cancer Invest ; 39(1): 84-97, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33058714

RESUMEN

Ubiquitin like with PHD and ring finger domains 1 (UHRF1) contributes to the progression of many cancers. Here, we firstly observed UHRF1 was elevated in cutaneous squamous cell carcinoma (cSCC) and related to the differentiation stages. Knockdown of UHRF1 in A431 and Scl-1 attenuated cell proliferation, migration, and invasion, leading to G2/M cell cycle arrest and apoptosis. Through a mouse xenograft model, we found UHRF1 deficiency ameliorated tumor growth. These results may be associated with destruction of multiple signal pathways. In summary, our results suggest UHRF1 is involved in the pathogenesis of cSCC and may be a therapeutic target.


Asunto(s)
Proteínas Potenciadoras de Unión a CCAAT/genética , Ubiquitina-Proteína Ligasas/genética , Animales , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Desnudos , Invasividad Neoplásica , Transducción de Señal , Neoplasias Cutáneas/patología
2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 35(6): 887-891, 2018 12 26.
Artículo en Zh | MEDLINE | ID: mdl-30583313

RESUMEN

Muscle atrophy of the residual limb after lower-limb amputation is a disadvantage of amputees' rehabilitation. To investigate the biomechanics mechanism of muscle atrophy of the residual limb, we built a finite element model of a residual limb including muscle, skeletons and main vessels based on magnetic resonance images of a trans-femoral amputee, and studied the biomechanics effects of the socket of the lower-limb prosthesis on the soft tissue and vessels in the residual limb. It was found that the descending branch of the lateral femoral circumflex artery suffered the most serious constriction due to the extrusion, while that of the deep femoral artery was comparatively light. Besides, the degree of the constriction of the descending branch of the lateral femoral circumflex vein, femoral vein and deep femoral vein decreased in turn, and that of the great saphenous vein was serious. The stress-strain in the anterior femoral muscle group were highest, while the stress concentration of the inferior muscle group was observed at the end of the thighbone, and other biomechanical indicators at the inferior region were also high. This study validated that the extrusion of the socket on the vessels could cause muscle atrophy to some degree, and provided theoretical references for learning the mechanism of muscle atrophy in residual limb and its effective preventive measures.

3.
Angew Chem Int Ed Engl ; 56(10): 2749-2753, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28128509

RESUMEN

Compared to the most popular directing-group-assisted strategy, the "undirected" strategy for C-H bond functionalization represents a more flexible but more challenging approach. Reported herein is a gold-catalyzed highly site-selective C(sp2 )-H alkylation of unactivated arenes with 2,2,2-trifluoroethyl α-aryl-α-diazoesters. This protocol demonstrates that high site-selective C-H bond functionalization can be achieved without the assistance of a directing group. In this transformation, both the gold catalyst and trifluoroethyl group on the ester of the diazo compound play vital roles for achieving the chemo- and regioselectivity.

4.
Zhongguo Yi Liao Qi Xie Za Zhi ; 41(3): 220-223, 2017 May 30.
Artículo en Zh | MEDLINE | ID: mdl-29862773

RESUMEN

Since the releasing of Order 650 in 2014, China Food and Drug Administration (CFDA) organized professionals to intensively formulate and revise regulations based on the original medical device supervision regulations system. Up to now, China medical device supervision new regulation system has been formed basically and has profound active implications on the whole medical device industry. The article analyzed the change of requirements of medical device supervision new regulation system from manufacture's point of view and tried to provide some simple suggestions of adapting them.


Asunto(s)
Aprobación de Recursos , Equipos y Suministros/normas , Regulación Gubernamental , China , Industrias , Control de Calidad , Estados Unidos
5.
J Biomech ; 171: 112197, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38905927

RESUMEN

Understanding the relationship between footwear features and their potential influence on running performance can inform the ongoing innovation of running footwear, aimed at pushing the limits of humans. A notable shoe feature is hollow structures, where an empty space is created in the midsole. Presently, the potential biomechanical effect of the hollow structures on running performance remains unknown. We investigated the role of hollow structures through quantifying the magnitude and timing of foot and footwear work. Sixteen male rearfoot runners participated in an overground running study in three shoe conditions: (a) a shoe with a hollow structure in the forefoot midsole (FFHS), (b) the same shoe without any hollow structure (Filled-FFHS) and (c) a shoe with a hollow structure in the midfoot midsole (MFHS). Distal rearfoot power was used to quantify the net power generated by foot and footwear together. The magnitude and timing of distal rearfoot work and ankle joint work were compared across shoe conditions. The results indicated that MFHS can significantly (p = 0.024) delay distal rearfoot energy return (3.4 % of stance) when compared to Filled-FFHS. Additionally, FFHS had the greatest positive (0.425 J/kg) and negative (-0.383 J/kg) distal rearfoot work, and the smallest positive (0.503 J/kg) and negative (-0.477 J/kg) ankle joint work among the three conditions. This showed that the size and location of the midsole hollow structure can affect timing and magnitude of energy storage and return. The forefoot hollow shoe feature can effectively increase distal rearfoot work and reduce ankle joint work during running.


Asunto(s)
Carrera , Zapatos , Humanos , Carrera/fisiología , Masculino , Adulto , Fenómenos Biomecánicos , Pie/fisiología , Articulación del Tobillo/fisiología , Diseño de Equipo , Adulto Joven
6.
J Biophotonics ; 17(3): e202300356, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38041219

RESUMEN

Cold atmospheric plasma (CAP) has been reported to kill melanoma cells in vitro and in vivo. BRAF and MEK inhibitors are targeted therapy agents for advanced melanoma patients with BRAF mutations. However, low overall survival and relapse-free survival are still tough challenges due to drug resistance. In this study, we confirmed that CAP alleviated innate drug resistance and promoted the anti-tumor effect of targeted therapy in A875 and WM115 melanoma cells in vitro. Further, we revealed that CAP altered the expression of various molecules concerning MAPK and PI3K-AKT pathways in A875 cells. This study demonstrates that CAP promises to work as adjuvant treatment with targeted therapy to overcome drug resistance for malignant tumors in future.


Asunto(s)
Antineoplásicos , Melanoma , Gases em Plasma , Humanos , Melanoma/tratamiento farmacológico , Melanoma/patología , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/farmacología , Fosfatidilinositol 3-Quinasas/uso terapéutico , Gases em Plasma/farmacología , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Proteínas Proto-Oncogénicas B-raf/uso terapéutico , Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Línea Celular Tumoral , Mutación
7.
J Dermatol Sci ; 113(3): 103-112, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38331641

RESUMEN

BACKGROUND: TET2 participates in tumor progression and intrinsic immune homeostasis via epigenetic regulation. TET2 has been reported to be involved in maintaining epithelial barrier homeostasis and inflammation. Abnormal epidermal barrier function and TET2 expression have been detected in psoriatic lesions. However, the mechanisms underlying the role of TET2 in psoriasis have not yet been elucidated. OBJECTIVE: To define the role of TET2 in maintaining epithelial barrier homeostasis and the exact epigenetic mechanism in the dysfunction of the epidermal barrier in psoriasis. METHODS: We analyzed human psoriatic skin lesions and datasets from the GEO database, and detected the expression of TET2/5-hmC together with barrier molecules by immunohistochemistry. We constructed epidermal-specific TET2 knockout mice to observe the effect of TET2 deficiency on epidermal barrier function via toluidine blue penetration assay. Further, we analyzed changes in the expression of epidermal barrier molecules by immunofluorescence in TET2-specific knockout mice and psoriatic model mice. RESULTS: We found that decreased expression of TET2/5-hmC correlated with dysregulated barrier molecules in human psoriatic lesions. Epidermal-specific TET2 knockout mice showed elevated transdermal water loss associated with abnormal epidermal barrier molecules. Furthermore, we observed that TET2 knockdown in keratinocytes reduced filaggrin expression via filaggrin promoter methylation. CONCLUSION: Aberrant epidermal TET2 affects the integrity of the epidermal barrier through the epigenetic dysregulation of epidermal barrier molecules, particularly filaggrin. Reduced TET2 expression is a critical factor contributing to an abnormal epidermal barrier in psoriasis.


Asunto(s)
Dioxigenasas , Psoriasis , Animales , Humanos , Ratones , Dioxigenasas/deficiencia , Dioxigenasas/genética , Dioxigenasas/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Epigénesis Genética , Proteínas Filagrina , Proteínas de Filamentos Intermediarios/genética , Proteínas de Filamentos Intermediarios/metabolismo , Queratinocitos/metabolismo , Ratones Noqueados , Psoriasis/patología
8.
Front Public Health ; 12: 1320932, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38439759

RESUMEN

Backgrounds: Observational studies have shown that cigarette smoking is inversely associated with risk of rosacea, However, it remains uncertain whether this association is causal or it is a result of reverse causation, and whether this association is affected by drinking behaviors. Methods: This study utilized the summary-level data from the largest genome-wide association study (GWAS) for smoking, alcohol consumption, and rosacea. The objective was to investigate the effect of genetically predicted exposures to smoking and alcohol consumption on the risk of developing rosacea. Two-sample bidirectional Mendelian randomization (MR) was applied, accompanied by sensitive analyses to validate the robustness of findings. Furthermore, multivariable MR was conducted to evaluate the direct impact of smoking on rosacea. Results: A decreased risk of rosacea was observed in individuals with genetically predicted lifetime smoking [odds ratio (OR)MR - IVW = 0.53; 95% confidence interval (CI), 0.318-0.897; P = 0.017], and number of cigarettes per day (ORMR - IVW = 0.55; 95% CI, 0.358-0.845; P = 0.006). However, no significant associations were found between initiation of regular smoking, smoking cessation, smoking initiation, alcohol consumption and rosacea. Reverse MR analysis did not show any associations between genetic liability toward rosacea and smoking or alcohol drinking. Importantly, the effect of lifetime smoking and the number of cigarettes per day on rosacea remained significant even after adjusting for alcohol consumption in multivariable MR analysis. Conclusion: Smoking was causally related to a lower risk of rosacea, while alcohol consumption does not appear to be associated with risk of rosacea.


Asunto(s)
Estudio de Asociación del Genoma Completo , Rosácea , Humanos , Análisis de la Aleatorización Mendeliana , Fumar/efectos adversos , Fumar/epidemiología , Consumo de Bebidas Alcohólicas/epidemiología , Rosácea/epidemiología
9.
Arch Dermatol Res ; 316(6): 333, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38844593

RESUMEN

BACKGROUND: Stiff skin syndrome (SSS) is a rare disease characterized by thickened, indurated skin and limited joint movement. Multiple diverse phenotypes have been reported, and the correlation of severity with the clinical heterogeneity and histopathological findings of SSS needs to be refined. OBJECTIVE: To define subtypes based on clinical features and predict the prognosis of a new SSS classification. METHODS: Eighty-three patients with SSS were retrospectively reviewed for clinicopathological manifestations and routine laboratory workup, including 59 cases obtained from a PubMed search between 1971 and 2022 and 24 cases diagnosed in our department between 2003 and 2022. RESULTS: Among the 83 patients, 27.7, 41, and 31.3% had classic widespread, generalized segmental, and localized SSS, respectively. Joint immobility was present in 100, 71, and 20% of classic, generalized, and localized cases, respectively. Histopathologic findings were common among the 3 groups, and based on that, we further found a difference in the distribution of proliferative collagen. 54.5% of classic and 50% of generalized cases occurred throughout the dermis or the subcutis, whereas 76% of localized cases were mainly involved in the reticular dermis or subcutis. In patients with incipient localized SSS, 42% (21/50) developed generalized SSS, and only 6% (3/50) progressed to classic SSS, whereas more than half of the incipient generalized SSS cases (60.6%, 20/33) developed classic SSS. LIMITATIONS: This retrospective study was limited to previously published cases with limited data. CONCLUSIONS: We propose a distinct clinical classification characterized by lesion distribution, including classic widespread, generalized segmental, and localized SSS, associated with disease severity and prognosis.


Asunto(s)
Piel , Humanos , Femenino , Masculino , Estudios Retrospectivos , Adulto , Persona de Mediana Edad , Adolescente , Piel/patología , Adulto Joven , Niño , Pronóstico , Enfermedades Cutáneas Genéticas/diagnóstico , Enfermedades Cutáneas Genéticas/clasificación , Enfermedades Cutáneas Genéticas/patología , Anciano , Índice de Severidad de la Enfermedad , Preescolar , Colágeno/metabolismo , Contractura
10.
J Control Release ; 367: 197-208, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38246205

RESUMEN

Melanoma, one of the most devastating forms of skin cancer, currently lacks effective clinical treatments. Delivery of functional genes to modulate specific protein expression to induce melanoma cell apoptosis could be a promising therapeutic approach. However, transfecting melanoma cells using non-viral methods, particularly with cationic polymers, presents significant challenges. In this study, we synthesized three branched poly(ß-amino ester)s (HPAEs) with evenly distributed branching units but varying space lengths through a two-step "oligomer combination" strategy. The unique topological structure enables HPAEs to condense DNA to form nano-sized polyplexes with favorable physiochemical properties. Notably, HPAEs, especially HPAE-2 with intermediate branching unit space length, demonstrated significantly higher gene transfection efficiency than the leading commercial gene transfection reagent, jetPRIME, in human melanoma cells. Furthermore, HPAE-2 efficiently delivered the Bax-encoding plasmid into melanoma cells, leading to a pronounced pro-apoptotic effect without causing noticeable cytotoxicity. This study establishes a potent non-viral platform for gene transfection of melanoma cells by harnessing the distribution of branching units, paving the way for potential clinical applications of gene therapy in melanoma treatment.


Asunto(s)
Ésteres , Melanoma , Polímeros , Humanos , Transfección , Ésteres/química , Melanoma/genética , Melanoma/terapia , Apoptosis , Técnicas de Transferencia de Gen
11.
Int J Biochem Cell Biol ; 145: 106190, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35248720

RESUMEN

OBJECTIVES: With the growing incidence of cutaneous squamous cell carcinoma (CSCC), the treatment-resistant invasive CSCC should be taken seriously. Retinoic acid receptor ß (RARß) functions as a tumor suppressor gene and is associated with the proliferation inhibition to retinoic acid. Demethylase TET2 directed epigenetic landscape contributes to cell malignant transform and is involved in therapeutic resistance in tumors. Whether aberrant TET2 participated in the deficient RARß remains largely unknown. Hereby, we identified the aberrant-TET2 directed epigenetic landscape contribute to the deficient RARß in CSCC. METHODS: The immunohistochemistry was used to detect the expression of RARß and TET2. The bisulfite sequencing PCR was used to detect the RARß promoter methylation. Plasmid transfection was used to upregulate TET2 in CSCC cells. Stable overxpressed TET2 cells were used to detect the effect of TET2 on RARß and drug sensitivity in the CCSC. RESULTS: We observed RARß decreased with promoter hypermethylation in CSCC and aberrant TET2 associated with deficient RARß. We upregulated TET2 could reverse promoter hypermethylation and showed a significantly increased expression of RARß, which enhanced the sensitivity of tumor cells to retinoic acid treatment. CONCLUSION: Aberrant TET2 leaded to the hypermethylation of RARß promoter, which contributed to the deficient RARß in CSCC. While reversing the hypermethylation of the RARß promoter by recovering the TET2 could enhance tumor cells to be sensitive to retinoic acid.


Asunto(s)
Carcinoma de Células Escamosas , Dioxigenasas , Neoplasias Cutáneas , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Metilación de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Dioxigenasas/genética , Dioxigenasas/metabolismo , Epigénesis Genética , Humanos , Receptores de Ácido Retinoico , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Tretinoina/farmacología
12.
J Biophotonics ; 15(6): e202100403, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35261164

RESUMEN

Cold atmospheric plasma (CAP) has attracted increasing attention due to its anti-bacterial and anti-tumor effects. Melanoma is an aggressive malignancy with increasing incidence rate and poor prognosis. Evaluating cell viability, apoptosis rate and reactive species injection efficiency of melanoma cells and human keratinocyte cells (HaCaT) treated with CAP to analyze biological safety of CAP. RNA-sequencing (RNA-seq) of A875 cells before and after treatment was performed to further explore the anti-tumor mechanism of CAP. CAP had a more significant biological effect on melanoma cells than HaCaT cells by inhibiting proliferation and promoting apoptosis. RNA-sequencing analysis showed that besides MAPK and p53 apoptotic signaling pathways, necroptosis and autophagy also played important roles in CAP-induced melanoma cells death. CAP can selectively kill melanoma cells and has good biosafety cytologically. Besides apoptosis, CAP can induce cell death via autophagy and necroptosis.


Asunto(s)
Melanoma , Gases em Plasma , Apoptosis/genética , Línea Celular Tumoral , Contención de Riesgos Biológicos , Humanos , Melanoma/genética , Melanoma/patología , Gases em Plasma/farmacología , ARN/farmacología
13.
Nat Commun ; 13(1): 1859, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35388001

RESUMEN

The cohesin complex participates in the organization of 3D genome through generating and maintaining DNA loops. Stromal antigen 2 (STAG2), a core subunit of the cohesin complex, is frequently mutated in various cancers. However, the impact of STAG2 inactivation on 3D genome organization, especially the long-range enhancer-promoter contacts and subsequent gene expression control in cancer, remains poorly understood. Here we show that depletion of STAG2 in melanoma cells leads to expansion of topologically associating domains (TADs) and enhances the formation of acetylated histone H3 lysine 27 (H3K27ac)-associated DNA loops at sites where binding of STAG2 is switched to its paralog STAG1. We further identify Interferon Regulatory Factor 9 (IRF9) as a major direct target of STAG2 in melanoma cells via integrated RNA-seq, STAG2 ChIP-seq and H3K27ac HiChIP analyses. We demonstrate that loss of STAG2 activates IRF9 through modulating the 3D genome organization, which in turn enhances type I interferon signaling and increases the expression of PD-L1. Our findings not only establish a previously unknown role of the STAG2 to STAG1 switch in 3D genome organization, but also reveal a functional link between STAG2 and interferon signaling in cancer cells, which may enhance the immune evasion potential in STAG2-mutant cancer.


Asunto(s)
Proteínas Cromosómicas no Histona , Melanoma , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Genoma , Humanos , Interferones/genética , Melanoma/genética
14.
J Microbiol Biotechnol ; 31(5): 747-755, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-33746191

RESUMEN

The effects of the gut microbiome on both allergy and autoimmunity in dermatological diseases have been indicated in several recent studies. Chronic spontaneous urticaria (CSU) is a disease involving allergy and autoimmunity, and there is no report detailing the role of microbiota alterations in its development. This study was performed to identify the fecal microbial composition of CSU patients and investigate the different compositions and potential genetic functions on the fecal microbiota between CSU patients and normal controls. The gut microbiota of CSU patients and healthy individuals were obtained by 16s rRNA massive sequencing. Gut microbiota diversity and composition were compared, and bioinformatics analysis of the differences was performed. The gut microbiota composition results showed that Firmicutes, Bacteroidetes, Proteobacteria, and Verrucomicrobia were dominant microbiota in CSU patients. The differential analysis showed that relative abundance of the Proteobacteria (p = 0.03), Bacilli (p = 0.04), Enterobacterales (p = 0.03), Enterobacteriaceae (p = 0.03) was significantly increased in CSU patients. In contrast, the relative abundance of Megamonas, Megasphaera, and Dialister (all p < 0.05) in these patients significantly decreased compared with healthy controls. The different microbiological compositions impacted normal gastrointestinal functions based on function prediction, resulting in abnormal pathways, including transport and metabolism. We found CSU patients exhibited gut microbiota dysbiosis compared with healthy controls. Our results indicated CSU is associated with gut microbiota dysbiosis and pointed out that the bacterial taxa increased in CSU patients, which might be involved in the pathogenesis of CSU. These results provided clues for future microbial-based therapies on CSU.


Asunto(s)
Urticaria Crónica/microbiología , Microbioma Gastrointestinal , Adulto , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Disbiosis/microbiología , Heces/microbiología , Femenino , Microbioma Gastrointestinal/genética , Humanos , Masculino , ARN Ribosómico 16S/genética
15.
J Biomed Mater Res A ; 109(4): 515-523, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32506791

RESUMEN

Porous three-dimensional (3D) silk fibroin (SF) scaffolds were widely applied for bone regeneration and showed excellent biocompatibility and biodegradability. Recently graphene was developed for bone scaffolds due to its osteogenic properties. Thus, we combine the SF and graphene to improve the osteogenic properties of SF scaffolds. In our study, we explored the incorporation of SF scaffolds with graphene to develop osteogenic scaffolds capable of accelerating bone formation. The 3D SF scaffolds were fabricated with different contents of graphene (0, 0.5, and 2%). Fluorescence images showed that the graphene nanosheets were homogeneously dispersed in the SF scaffolds. The addition of graphene affected the microarchitecture of the scaffolds. The G/SF scaffolds were cocultured with rat bone marrow-derived mesenchymal stem cells (rBMSCs) for 21 days. The cell morphology and cell proliferation study suggested that 0 and 0.5% G/SF scaffolds displayed good cell proliferation. In addition, immunofluorescent staining (e.g., osteonectin, osteopontin, and osteocalcin) and ALP activities indicated that the osteogenic properties was more actively exhibited on 0.5% G/SF scaffolds compared with the other groups. Our results indicated that SF scaffolds incorporated with graphene could be an appropriate scaffold for bone tissue engineering.


Asunto(s)
Regeneración Ósea , Fibroínas/química , Grafito/química , Células Madre Mesenquimatosas/citología , Andamios del Tejido/química , Animales , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Ratas , Ingeniería de Tejidos/métodos
16.
J Biomech ; 119: 110208, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33662748

RESUMEN

Measuring the location of necrotic lesions is necessary to diagnosis of osteonecrosis. Different region segmentation methods of the femoral head were proposed to quantitatively measure necrotic lesions including Japanese Investigation Committee for Avascular Necrosis (JIC) classification and China-Japan Friendship Hospital (CJFH) classification. Biomechanical methods could bring important information to evaluate the reasonability of these classifications. In this study, microstructural and mechanical properties of trabecular bone were quantitatively analyzed according to the region segmentation methods described in these classifications. Microstructural parameters of trabecular bone were analyzed based on micro-CT scanning. Mechanical properties were measured through Nanoindentation and micro-finite element analysis. It was found that microstructural and mechanical properties of trabecular bone in the middle region was more adaptive to load bearing than the medial and lateral regions according to the CJFH classification; lesions in the middle region could bring more changes to microstructure and stress distribution. According to JIC classification, differences of microstructural and mechanical properties among the three regions were not significant. Biomechanical characteristics of trabecular bones could be better distinguished with CJFH classification.


Asunto(s)
Osteonecrosis , Cabeza Femoral , Análisis de Elementos Finitos , Humanos , Osteonecrosis/diagnóstico por imagen , Estrés Mecánico , Soporte de Peso , Microtomografía por Rayos X
17.
Int J Oncol ; 54(5): 1534-1544, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30816486

RESUMEN

Cell division cycle 20 (CDC20) is a regulatory molecule and serves critical roles at multiple points of the cell cycle. Recent evidence indicates that CDC20 may serve an oncogenic role in a number of human cancer types. However, the role of CDC20 in primary cutaneous squamous cell carcinoma (cSCC) has not been studied, to the best of our knowledge. The aim of the present study was to investigate whether and how CDC20 is involved in the tumorigenesis of cSCC. The results revealed that CDC20 expression was significantly increased in cSCC tissues and cell lines, and its expression was associated with pathological differentiation. Downregulation of CDC20 inhibited cell proliferation, induced cell cycle arrest, promoted apoptosis and reduced migratory ability through inhibition of the Wnt/ß­catenin signaling pathway. Furthermore, all­trans­retinoic acid treatment significantly downregulated CDC20 expression in cSCC. The present results revealed that CDC20 may serve a crucial role in human cSCC, and suggested that CDC20 may be a novel biomarker for the prevention, diagnosis and treatment of cSCC.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Proteínas Cdc20/genética , Proteínas Cdc20/metabolismo , Neoplasias Cutáneas/metabolismo , Regulación hacia Arriba , Vía de Señalización Wnt , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Niño , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Adulto Joven
18.
J Invest Dermatol ; 139(4): 796-806, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30414907

RESUMEN

Recent studies showed that TWEAK/Fn14 signaling participates in the progression of internal malignancies. However, its role in the biological properties of cutaneous squamous cell carcinoma (SCC) remains unclear. This study was designed to explore the effect of TWEAK/Fn14 activation on cutaneous SCC as well as the relevant mechanism. The expression of TWEAK and Fn14 was determined in tissue samples of patients with cutaneous SCC. Human primary keratinocytes and SCC cell lines were cultured in vitro, receiving stimulation of TWEAK. The xenografts of SCC were generated subcutaneously in BALB/c nude mice. The results showed that both TWEAK and Fn14 were highly expressed in human cutaneous SCC. Moreover, TWEAK/Fn14 activation promoted the proliferation, migration, and invasion of cultured SCC cells. Interestingly, TNFR2 was upregulated in cultured SCC cells, and the transfection of TNFR2 small interfering RNA abrogated the effect of TWEAK on these cells. Finally, the favorable effect of TWEAK/Fn14 signals was confirmed in BALB/c nude mice with SCC xenografts. In conclusion, TWEAK/Fn14 signals contribute to the progression of cutaneous SCC, possibly involving the TNF-α-independent TNFR2 signal transduction.


Asunto(s)
Carcinoma de Células Escamosas/genética , ADN de Neoplasias/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Cutáneas/genética , Piel/patología , Receptor de TWEAK/genética , Western Blotting , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Humanos , Inmunohistoquímica , Transducción de Señal , Piel/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Receptor de TWEAK/biosíntesis
19.
J Biomech ; 74: 98-105, 2018 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-29735265

RESUMEN

Insufficient scaffolding time in the process of rapid corrosion is the main problem of magnesium alloy stent (MAS). Finite element method had been used to investigate corrosion of MAS. However, related researches mostly described all elements suffered corrosion in view of one-dimensional corrosion. Multi-dimensional corrosions significantly influence mechanical integrity of MAS structures such as edges and corners. In this study, the effects of multi-dimensional corrosion were studied using experiment quantitatively, then a phenomenological corrosion model was developed to consider these effects. We implemented immersion test with magnesium alloy (AZ31B) cubes, which had different numbers of exposed surfaces to analyze differences of dimension. It was indicated that corrosion rates of cubes are almost proportional to their exposed-surface numbers, especially when pitting corrosions are not marked. The cubes also represented the hexahedron elements in simulation. In conclusion, corrosion rate of every element accelerates by increasing corrosion-surface numbers in multi-dimensional corrosion. The damage ratios among elements with the same size are proportional to the ratios of corrosion-surface numbers under uniform corrosion. The finite element simulation using proposed model provided more details of changes of morphology and mechanics in scaffolding time by removing 25.7% of elements of MAS. The proposed corrosion model reflected the effects of multi-dimension on corrosions. It would be used to predict degradation process of MAS quantitatively.


Asunto(s)
Implantes Absorbibles , Aleaciones/química , Magnesio/química , Stents , Corrosión , Análisis de Elementos Finitos
20.
Biomed Res Int ; 2018: 4025083, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30515396

RESUMEN

Osteogenic differentiation of cells has considerable clinical significance in bone defect treatment, and cell behavior is linked to extracellular matrix stiffness. This study aimed to determine how matrix stiffness affects cell morphology and subsequently regulates the osteogenic phenotype of osteogenesis precursor cells. Four PDMS substrates were prepared with stiffness corresponding to the elastic modulus ranging from 0.6 MPa to 2.7 MPa by altering the Sylgard 527 and Sylgard 184 concentrations. MC3T3-E1 cells were cultured on the matrices. Cell morphology, vinculin expression, and key osteogenic markers, Col I, OCN, OPN, and calcium nodule, were examined. The activity and expression level of Yes-associated protein (YAP) were evaluated. Results showed that cell spreading exhibited no correlation with the stiffness of matrix designed in this paper, but substratum stiffness did modulate MC3T3-E1 osteogenic differentiation. Col I, OPN, and OCN proteins were significantly increased in cells cultured on soft matrices compared with stiff matrices. Additionally, cells cultured on the 1:3 ratio matrices had more nodules than those on other matrices. Accordingly, cells on substrates with low stiffness showed enhanced expression of the osteogenic markers. Meanwhile, YAP expression was downregulated on soft substrates although the subcellular location was not affected. Our results provide evidence that matrix stiffness (elastic modulus ranging from 0.6 MPa to 2.7 MPa) affects the osteogenic differentiation of MC3T3-E1, but it is not that "the stiffer, the better" as showed in some of the previous studies. The optimal substrate stiffness may exist to promote osteoblast differentiation. Cell differentiation triggered by the changes in substrate stiffness may be independent of the YAP signal. This study has important implications for biomaterial design and stem cell-based tissue engineering.


Asunto(s)
Desarrollo Óseo/genética , Diferenciación Celular/genética , Osteogénesis/genética , Ingeniería de Tejidos , Células 3T3 , Animales , Proliferación Celular/genética , Forma de la Célula/genética , Elasticidad/fisiología , Matriz Extracelular/genética , Humanos , Ratones , Osteoblastos/citología , Osteoblastos/metabolismo
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