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1.
Gerontology ; 70(1): 59-75, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37827130

RESUMEN

INTRODUCTION: Osteoarthritis (OA) is the most prevalent and debilitating joint disease without an effective therapeutic option. Multiple risk factors for OA have been identified, including abnormal chondrocyte miRNA secretion and circadian rhythms disruption, both of which have been found to cause progressive damage and loss of articular cartilage. Environmental disruption of circadian rhythms in mice predisposes animals to cartilage injury and OA. METHODS: The role of miR-195/497 cluster during OA progression was verified by mouse OA model with intra-articular injection of Agomir and Antagomir. We performed micro-CT analysis, Osteoarthritis Research Society International scores, and histological analysis in mouse knee joints. RNA sequencing was performed on the mouse cartilage cell line to explore the molecular mechanism of the miR-195/497 cluster and proteins in signaling pathway were evaluated using Western blot. Senescence-associated phenotypes were detected by Western blot, senescence ß-galactosidase staining, and immunofluorescence. RESULTS: This study demonstrated that miR-195/497-5p expression is disrupted in OA with senescent chondrocytes. In addition, miR-195/497-5p influenced the circadian rhythm of mice chondrocytes by modulating the expression of the Per2 protein, resulting in the gradual degradation of articular cartilage. We found that the miR-195/497 cluster targets DUSP3 expression. The deletion of the miR-195/497 cluster increased the level of DUSP3 expression and decreased the levels of phosphorylated ERK 1/2 and CREB. Per2 transcription is upregulated by stimulating CREB and ERK 1/2 phosphorylation. CONCLUSION: Our findings identify a regulatory mechanism connecting chondrocyte miR-195/497-5p to cartilage maintenance and repair and imply that circadian rhythm disturbances affected by miR-195/497-5p are risk factors for age-related joint diseases such as OA.


Asunto(s)
Cartílago Articular , Relojes Circadianos , MicroARNs , Osteoartritis , Ratones , Animales , Relojes Circadianos/genética , MicroARNs/genética , Osteoartritis/genética , Osteoartritis/metabolismo , Condrocitos/metabolismo , Cartílago Articular/metabolismo , Modelos Animales de Enfermedad
2.
Small ; 19(36): e2206919, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37183293

RESUMEN

The regeneration of diabetic bone defects remains challenging. Hyperglycemia causes inflammation state and excessive reactive oxygen species (ROS) during bone regeneration period. These two effects reinforce one another and create an endless loop that is also accompanied by mitochondrial dysfunction. However, there is still no effective and inclusive method targeting at the two aspects and breaking the vicious cycle. Herein, nanoparticles-Met@ZIF-8(metformin loaded zeolitic imidazolate frameworks) modified hydrogel that is capable of releasing metformin and Zn elements are constructed. This hydrogel treats hyperglycemia while also controlling mitochondrial function, reducing inflammation, and restoring homeostasis. In addition, the synergetic effect from metformin and Zn ions inhibits ROS-inflammation cascade generation and destroys the continuous progress by taking effects in both ROS and inflammation and further keeping organelles' homeostasis. Furthermore, with the recovery of mitochondria and breakdown of the ROS-inflammation cascade cycle, osteogenesis under a diabetic microenvironment is enhanced in vivo and in vitro. In conclusion, the study provides critical insight into the biological mechanism and potential therapy for diabetic bone regeneration.


Asunto(s)
Diabetes Mellitus , Hiperglucemia , Estructuras Metalorgánicas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Hidrogeles
3.
J Mater Sci Mater Med ; 34(11): 57, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37938467

RESUMEN

Early fracture fixation is the critical factor in fracture healing. Common internal fracture implants are made of metallic materials, which often affects the imaging quality of CT and MRI. Most patients will choose secondary surgery to remove the internal fixation implants, which causes secondary damage to them. The development of new degradable internal fracture implants has attracted more and more attention from orthopedic surgeons and researchers. Based on these problems, we improved the various properties of medical grade polycaprolactone (PCL) by adding poly(L-lactide) (PLLA). We produced PCL/PLLA strapping bands with different mass ratios by injection molding. We compared the mechanical properties, degradation properties, cell biocompatibility, bone marrow mesenchymal stem cells (BMSCs) adhesion, proliferation, osteogenic differentiation and fracture fixation effect of these strapping bands. The results showed that the tensile strength and yield force of the strapping bands increased with the increase of the content of PLLA. The addition of PLLA could significantly improve the mechanical strength in the early stage and accelerate the degradation rate of the strapping band. PCL/PLLA (80/20) strapping band had no significant cytotoxicity toward rBMSCs and could promote osteogenic differentiation of rBMSCs. The strapping band could ensure femoral fracture healing of beagles in 3 months and didn't cause damage to the surrounding tissues and main organs. This study will provide some new insights into the biodegradable products of PCL/PLLA blends for internal fixation of fracture. We produced novel degradable PCL/PLLA strapping bands with different mass ratios by injection molding. We tested the biological safety of the prepared internal fixation strapping bands for fracture, such as cell experiment in vitro and animal experiment, and studied the degradation behavior in vitro. The strapping bands could ensure femoral fracture healing of beagles. This study will provide some new insights into the biodegradable products of PCL/PLLA blends for internal fixation of fracture. A Immunofluorescence staining of rBMSCs (live cells: green; dead cells: red). B Young's modulus change curve during strapping bands degradation. C The implantation process of strapping bands. D Micro-CT images of the beagle's fracture recovery after the operation.


Asunto(s)
Fracturas del Fémur , Osteogénesis , Animales , Perros , Humanos , Fijación Interna de Fracturas , Fracturas del Fémur/cirugía , Curación de Fractura , Materiales Biocompatibles
4.
Mol Biol Rep ; 49(12): 12063-12075, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36315326

RESUMEN

BACKGROUND: Recently biomaterials utilized for designing scaffolds in tissue engineering are not cost-effective and eco-friendly. As a result, we design and develop biocompatible and bioactive hydrogels for osteo-tissue regeneration based on the natural polysaccharide chitosan. Three distinct hydrogel components were used for this. METHODS: Hydrogels networks were created using chitosan 2% (CTS 2%), carboxymethyl chitosan 2% (CMC 2%), and 50:50 mixtures of CTS and CMC (CTS/CMC 50:50). Furthermore, scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), degradation, and swelling behavior of design hydrogels were studied. Also, the cytocompatibility and osteo-differentiation potency were examined by encapsulating mesenchymal stem cells derived from adipose tissue (AMSCs) on the designed hydrogels. RESULTS: According to the findings, our results showed an acceptable pore structure, functional groups, and degradation rate of the designed hydrogels for in vitro evaluation. In addition, employing CMC instead of CTS or adding 50% CMC to the hydrogel component could improve the hydrogel's osteo-bioactivity without the use of external osteogenic differentiation agents. CONCLUSION: The CMC-containing hydrogel not only caused early osteogenesis but also accelerated differentiation to the maturity phase of osteoblasts.


Asunto(s)
Quitosano , Células Madre Mesenquimatosas , Hidrogeles/farmacología , Hidrogeles/química , Quitosano/farmacología , Osteogénesis , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular , Ingeniería de Tejidos/métodos , Andamios del Tejido
5.
Sensors (Basel) ; 22(11)2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-35684633

RESUMEN

Power line communication (PLC) is an important interconnection technology for the smart grid, but the robustness of PLC transmission is faced with a great challenge due to strong non-Gaussian noise and interference. In this paper, a narrowband interference (NBI) resistant preamble is designed, and an effective timing and frequency synchronization method is proposed for OFDM-based PLC systems in the smart grid, which is capable of simultaneously conveying some bits of transmission parameter signaling (TPS) as well. In the time domain, the cyclic extension of the training OFDM symbol is scrambled, which makes it feasible to combat against NBI contamination. More accurate timing detection and sharper correlation peak can be implemented under the power line channel and the AWGN channel in the presence of NBI, compared with the conventional Schmidl's and Minn's methods with the same preamble length. Furthermore, the TPS transmitted using the proposed method is also immune from the NBI. The proposed method is capable of improving the synchronization performance of the PLC transmission significantly, which is verified by theoretical analysis and computer simulations.

6.
J Environ Manage ; 308: 114613, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35124310

RESUMEN

A novel core-shell structured Fe3O4@GO-CoPc magnetic catalyst, which is with magnetite (Fe3O4) as the core, graphene oxide (GO) as the interlayer and cobalt-phthalocyanine (CoPc) as the shell, was successfully prepared and used as a heterogeneous photo-Fenton catalyst for tetracycline (TC) degradation in this work. The core-shell structure of the catalyst was confirmed by XRD, FTIR, SEM and TEM. BET and magnetic hysteresis loops measurements indicated that Fe3O4@GO-CoPc catalyst owned large specific surface area and could be easily recovered under an external magnetic field. Meanwhile, the experimental results of TC degradation demonstrated that the photo-Fenton efficiency of Fe3O4@GO-CoPc was excellent. When the reaction time was 120 min, TC could be degraded almost completely in the photo-Fenton system with Fe3O4@GO-CoPc. The high photo-Fenton catalytic activity of Fe3O4@GO-CoPc could be resulted from the effective transfer of photo-generated electrons between CoPc and Fe3O4 by GO. Moreover, the main reaction species, •OH, O2•-, 1O2 and h+, were verified by the analysis of active species in this system. Finally, the mechanism analyses and quantitative analysis results of active species indicated that the introduction of GO accelerated the cycle between Fe(II) and Fe(III) as well as improved the effective utilization of H2O2 (the efficiency of conversion of H2O2 to •OH).


Asunto(s)
Grafito , Peróxido de Hidrógeno , Catálisis , Compuestos Férricos , Grafito/química , Peróxido de Hidrógeno/química , Tetraciclina
7.
J Biol Chem ; 295(13): 4237-4251, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-32075910

RESUMEN

Parkinson disease autosomal recessive, early onset 7 (PARK7 or DJ-1) is involved in multiple physiological processes and exerts anti-apoptotic effects on multiple cell types. Increased intestinal epithelial cell (IEC) apoptosis and excessive activation of the p53 signaling pathway is a hallmark of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD). However, whether DJ-1 plays a role in colitis is unclear. To determine whether DJ-1 deficiency is involved in the p53 activation that results in IEC apoptosis in colitis, here we performed immunostaining, real-time PCR, and immunoblotting analyses to assess DJ-1 expression in human UC and CD samples. In the inflamed intestines of individuals with IBD, DJ-1 expression was decreased and negatively correlated with p53 expression. DJ-1 deficiency significantly aggravated colitis, evidenced by increased intestinal inflammation and exacerbated IEC apoptosis. Moreover, DJ-1 directly interacted with p53, and reduced DJ-1 levels increased p53 levels both in vivo and in vitro and were associated with decreased p53 degradation via the lysosomal pathway. We also induced experimental colitis with dextran sulfate sodium in mice and found that compared with DJ-1-/- mice, DJ-1-/-p53-/- mice have reduced apoptosis and inflammation and increased epithelial barrier integrity. Furthermore, pharmacological inhibition of p53 relieved inflammation in the DJ-1-/- mice. In conclusion, reduced DJ-1 expression promotes inflammation and IEC apoptosis via p53 in colitis, suggesting that the modulation of DJ-1 expression may be a potential therapeutic strategy for managing colitis.


Asunto(s)
Inflamación/genética , Enfermedades Inflamatorias del Intestino/genética , Proteína Desglicasa DJ-1/genética , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis/genética , Colitis Ulcerosa/genética , Colitis Ulcerosa/patología , Enfermedad de Crohn/genética , Enfermedad de Crohn/patología , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Humanos , Inflamación/inducido químicamente , Inflamación/patología , Enfermedades Inflamatorias del Intestino/inducido químicamente , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Lisosomas/genética , Ratones , Transducción de Señal
8.
Br J Cancer ; 125(7): 1003-1015, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34247196

RESUMEN

BACKGROUND: Metastasis is the major cause of treatment failure and cancer-related deaths in prostate cancer (PCa) patients. Our previous study demonstrated that a CD44+ subpopulation isolated from PCa cells or tumours possesses both stem cell properties and metastatic potential, serving as metastatic prostate cancer stem cells (mPCSCs) in PCa metastasis. However, the underlying mechanisms remain unknown. METHODS: In this study, we established PCa models via the orthotopic and subcutaneous implantation of different human PCa cancer cell lines, and compared the metastatic efficacy, after which process function analysis of target genes was pinpointed. RESULTS: Several novel differentially expressed genes (DEGs) between orthotopic and ectopic tumours were identified. Among them, human homeobox B9 (HOXB9) transcription factor was found to be essential for PCa metastasis, as evidenced by the diminished number of lung metastatic foci derived from orthotopic implantation with HOXB9-deficient CWR22 cells, compared with the control. In addition, HOXB9 protein expression was upregulated in PCa tissues, compared with paracancer and benign prostate hyperplasia tissues. It was also positively correlated with Gleason scores. Gain- and loss-of-function assays showed that HOXB9 altered the expression of various tumour metastasis- and cancer stem cell (CSC) growth-related genes in a transforming growth factor beta (TGFß)-dependent manner. Moreover, HOXB9 was overexpressed in an ALDH+CD44+CXCR4+CD24+ subpopulation of PCa cells that exhibited enhanced TGFß-dependent tumorigenic and metastatic abilities, compared with other isogenic PCa cells. This suggests that HOXB9 may contribute to PCa tumorigenesis and metastasis via TGFß signalling. Of note, ALDH+CD44+CXCR4+CD24+-PCa cells exhibited resistance to castration and antiandrogen therapy and were present in human PCa tissues. CONCLUSION: Taken together, our study identified HOXB9 as a critical regulator of metastatic mPCSC behaviour. This occurs through altering the expression of a panel of CSC growth- and invasion/metastasis-related genes via TGFß signalling. Thus, targeting HOXB9 is a potential novel therapeutic PCa treatment strategy.


Asunto(s)
Proteínas de Homeodominio/metabolismo , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/secundario , Células Madre Neoplásicas/metabolismo , Neoplasias de la Próstata/patología , Animales , Línea Celular Tumoral , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Proteínas de Homeodominio/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Ratones , Clasificación del Tumor , Trasplante de Neoplasias , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Regulación hacia Arriba
9.
Hepatobiliary Pancreat Dis Int ; 20(5): 469-477, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34348873

RESUMEN

BACKGROUND: Liver injury is one of the most common complications during sepsis. Macrophage migration inhibitory factor (MIF) is an important proinflammatory cytokine. This study explored the role of MIF in the lipopolysaccharide (LPS)-induced liver injury through genetically manipulated mouse strains. METHODS: The model of LPS-induced liver injury was established in wild-type and Mif-knockout C57/BL6 mice. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TBil) were detected, and the expressions of MIF, tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) were measured. Liver histopathology was conducted to assess liver injury. Moreover, the inhibitions of MIF with (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester (ISO-1) and 4-iodo-6-phenylpyrimidine (4-IPP) were used to evaluate their therapeutic potential of liver injury. RESULTS: Compared with wild-type mice, the liver function indices and inflammation factors presented no significant difference in the Mif-/- mice. After 72 h of the LPS-induced liver injury, serum levels of ALT, AST, and TBil as well as TNF-α and IL-1ß were significantly increased, but the knockout of Mif attenuated liver injury and inflammatory response. In liver tissue, mRNA levels of TNF-α, IL-1ß and NF-κB p65 were remarkably elevated in LPS-induced liver injury, while the knockout of Mif reduced these levels. Moreover, in LPS-induced liver injury, the inhibitions of MIF with ISO-1 and 4-IPP alleviated liver injury and slightly attenuated inflammatory response. Importantly, compared to mice with LPS-induced liver injury, Mif knockout or MIF inhibitions significantly prolonged the survival of the mice. CONCLUSIONS: In LPS-induced liver injury, the knockout of Mif or MIF inhibitions alleviated liver injury and slightly attenuated inflammatory response, thereby prolonged the survival of the mice. Targeting MIF may be an important strategy to protect the liver from injury during sepsis.


Asunto(s)
Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Factores Inhibidores de la Migración de Macrófagos , Sepsis , Animales , Técnicas de Inactivación de Genes , Lipopolisacáridos/toxicidad , Hígado , Factores Inhibidores de la Migración de Macrófagos/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor de Necrosis Tumoral alfa/genética
10.
J Cell Mol Med ; 24(17): 10112-10127, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32790170

RESUMEN

Postmenopausal Osteoporosis (PMOP) is oestrogen withdrawal characterized of much production and activation by osteoclast in the elderly female. Cytisine is a quinolizidine alkaloid that comes from seeds or other plants of the Leguminosae (Fabaceae) family. Cytisine has been shown several potential pharmacological functions. However, its effects on PMOP remain unknown. This study designed to explore whether Cytisine is able to suppress RANKL-induced osteoclastogenesis and prevent the bone loss induced by oestrogen deficiency in ovariectomized (OVX) mice. In this study, we investigated the effect of Cytisine on RAW 264.7 cells and bone marrow monocytes (BMMs) derived osteoclast culture system in vitro and observed the effect of Cytisine on ovariectomized (OVX) mice model to imitate postmenopausal osteoporosis in vivo. We found that Cytisine inhibited F-actin ring formation and tartrate-resistant acid phosphatase (TRAP) staining in dose-dependent ways, as well as bone resorption by pit formation assays. For molecular mechanism, Cytisine suppressed RANK-related trigger RANKL by phosphorylation JNK/ERK/p38-MAPK, IκBα/p65-NF-κB, and PI3K/AKT axis and significantly inhibited these signalling pathways. However, the suppression of PI3K-AKT-NFATc1 axis was rescued by AKT activator SC79. Meanwhile, Cytisine inhibited RANKL-induced RANK-TRAF6 association and RANKL-related gene and protein markers such as NFATc1, Cathepsin K, MMP-9 and TRAP. Our study indicated that Cytisine could suppress bone loss in OVX mouse through inhibited osteoclastogenesis. All data provide the evidence that Cytisine may be a promising agent in the treatment of osteoclast-related diseases such as osteoporosis.


Asunto(s)
Alcaloides/metabolismo , Resorción Ósea/metabolismo , Osteoclastos/metabolismo , Osteogénesis/fisiología , Ligando RANK/metabolismo , Animales , Azocinas/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Ovariectomía/métodos , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinolizinas/metabolismo , Células RAW 264.7 , Transducción de Señal/fisiología
11.
Biochem Biophys Res Commun ; 526(3): 670-677, 2020 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-32248969

RESUMEN

Growing studies have indicated the involvements of long noncoding RNAs (lncRNAs) in the initiation and progression of various tumors. We aimed to investigated the role of lncRNA LMCD1 antisense RNA 1 (LMCD1-AS1) in osteosarcoma development. We found that LMCD1-AS1 and SP1 were highly expressed in osteosarcoma tissues and cell lines. High levels of LMCD1-AS1 were correlated with positively metastasis and poor clinical prognosis. Moreover, we showed that SP1 can bind to the promoter region of LMCD1-AS1, resulting in its overexpression in osteosarcoma. Functionally, silencing of LMCD1-AS1 suppressed the proliferation, migration, invasion and EMT progress of osteosarcoma cells. Mechanistic studies revealed that LMCD1-AS1 was a sponge of miR-106b-5p activity. LMCD1-AS1 modulated survival of osteosarcoma via targeting miR-106b-5p. Overall, we firstly indicated that LMCD1-AS1 overexpression contributes to osteosarcoma development and poor clinical outcome, suggesting that LMCD1-AS1 may be a novel diagnostic and prognostic biomarker for osteosarcoma and a target for osteosarcoma therapy.


Asunto(s)
Neoplasias Óseas/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , Osteosarcoma/genética , ARN Largo no Codificante/genética , Factor de Transcripción Sp1/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Proliferación Celular , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Femenino , Humanos , Masculino , Osteosarcoma/patología , Regulación hacia Arriba
12.
Mikrochim Acta ; 185(9): 431, 2018 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-30155793

RESUMEN

Nitrogen-doped graphene quantum dots (NGQDs) are shown to strongly enhance the integrated chemiluminescence (CL) of the permanganate-sulfite system. The mechanism of enhancement was investigated, and the catalytic effect of the NGQDs was proven. In contrast to other carbon-based nanomaterials, the enhancement by NGQDs is independent of particle size and surface. However, the pyridinic nitrogen on the surface of the NGQDs facilitates the transformation of dissolved oxygen into H2O2 and the generation of hydroxyl radicals. This induces the increase of CL intensity. However, in the presence of Fe3+, the nitrogen functions and phenol groups on the surface of the NGQDs will chelate it, and the CL signal is decreased as a result. This effect was used to design an assay for Fe3+ that has a wide response range (1 × 10-8 - 1 × 10-6 M) and a 4 nM detection limit. The method was successfully applied to the determination of Fe3+ in spiked real water samples. Graphical abstract Nitrogen-doped graphene quantum dots (NGQDs) are demonstrated to strongly enhance the integrated chemiluminescence (CL) of the permanganate-sulfite system. The pyridinic N-atoms in NGQDs facilitate the transformation from dissolved oxygen into H2O2 and the generation of •OH radicals. This leads to the highly enhanced CL of the system. In the presence of Fe3+, which will be chelated by the nitrogen functions and phenol groups on the surface of the NGQDs, the CL signal is decreased.

13.
J Hand Surg Am ; 42(6): 471.e1-471.e6, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28365147

RESUMEN

PURPOSE: A chevron osteotomy of the ulna is widely used to obtain intra-articular access to the elbow in the treatment of type C distal humerus fractures. The trochlear notch of the proximal ulna is divided into 2 articular parts by the "bare area." Ideally, the olecranon osteotomy should be centered on the bare area to minimize damage to the joint cartilage. The goals of this study were to describe the anatomy of the bare area and design an ideal chevron-shaped osteotomy. METHODS: We dissected 38 cadaver elbows and measured the width of the bare area, the distance between the tip of the triceps insertion and the area on the olecranon cortex corresponding to the bare area. We then designed a chevron osteotomy to stay within the bare area and measured the distance from the tip of the triceps insertion to the osteotomy apex as well as the angle of the osteotomy plane and the angle of the chevron cuts. RESULTS: The bare area existed in all 38 cadavers. The mean longitudinal and transverse widths were 4.0 mm (range, 1.0-8.6 mm) and 19.0 mm (range, 16.9-23.8 mm), respectively. The mean distance between the tip of the triceps insertion and the area on the olecranon cortex corresponding to the bare area was 19.0 mm (range, 16.0-23.0 mm). The mean transverse and longitudinal widths of the cortical notch were 3.0 mm (range, 1.6-4.5 mm) and 8.0 mm (range, 6.5-14.8 mm), respectively. The mean distance between the tip of the triceps insertion and the osteotomy apex was 22.0 mm (range, 18.0-24.0 mm) and the mean angle between the osteotomy surface and the vertical plane corresponding to the tangent plane was 20° (range, 10° to 25°). The mean angle of the V shape was 140° (range, 130° to 150°). CONCLUSIONS: Using the narrowest edge lacking cartilage (lateral or medial side) as a point of reference to locate the bare area, the designed chevron osteotomy entered the joint in the bare area in most specimens and decreased associated damage to the joint cartilage. CLINICAL RELEVANCE: This study describes the anatomy of the bare area and the design of the ideal chevron-shaped osteotomy to treat type C distal humerus fractures.


Asunto(s)
Articulación del Codo/patología , Osteotomía/métodos , Cúbito/patología , Cúbito/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Articulación del Codo/cirugía , Femenino , Humanos , Fracturas del Húmero/cirugía , Masculino , Persona de Mediana Edad
14.
J Hepatol ; 64(4): 925-32, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26639394

RESUMEN

BACKGROUND & AIMS: Hyperuricemia significantly increases risk of non-alcoholic fatty liver disease (NAFLD) and insulin resistance. However, the mechanisms responsible for this association are as yet unclear. This study aimed to investigate the effects and underlying mechanisms of uric acid on development of NAFLD and insulin resistance. METHODS: We initially analyzed the impact of uric acid on the development of hepatic steatosis and insulin resistance in mice and in two cell models, HepG2 and L02. Subsequently, we studied the role of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome in uric acid-induced fat accumulation and insulin signaling impairment. RESULTS: We found that uric acid directly induces hepatocyte fat accumulation, insulin resistance, and insulin signaling impairment both in vivo and in vitro. We also found that uric acid-induced NLRP3 inflammasome activation, whereas lowering uric acid by allopurinol inhibited NLRP3 inflammasome activation in a high fat diet mouse model of NAFLD. Moreover, knocking down NLRP3 expression significantly attenuated uric acid-induced fat accumulation both in HepG2 cells and L02 cells. Knocking down NLRP3 expression also rescued uric acid-induced insulin signaling impairment in both cell types. CONCLUSIONS: Uric acid regulates hepatic steatosis and insulin resistance through the NLRP3 inflammasome. Uric acid may be a new therapeutic target for NAFLD and insulin resistance.


Asunto(s)
Hígado Graso/inducido químicamente , Inflamasomas/fisiología , Resistencia a la Insulina , Proteína con Dominio Pirina 3 de la Familia NLR/fisiología , Ácido Úrico/farmacología , Proteínas Quinasas Activadas por AMP/fisiología , Animales , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
15.
Surg Endosc ; 30(11): 5099-5107, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27005293

RESUMEN

INTRODUCTION: Endoscopic submucosal dissection (ESD) has been used for the treatment of gastric submucosal tumors (SMTs). This study aims to compare clinical outcomes of ESD versus laparoscopic wedge resection (LWR) for gastric SMTs. METHODS: This is a retrospective cohort study. Patients with SMTs who underwent ESD or LWR were enrolled in this study at a university-affiliated hospital from January 2010 to October 2015. Preoperative endoscopic ultrasound and computed tomography were performed to determine origin of layer and growth pattern. Clinical outcomes including baseline demographics, tumor size, operation time, blood loss, hospital stay, cost, pathology and postoperative complications were compared. RESULTS: From January 2010 to October 2015, 68 patients with SMTs received ESD and 47 patients with SMTs received LWR. There was no difference in age, gender, body mass index, origin of layer and proportion with symptoms between ESD group and LWR group. However, tumor size was significantly larger in the LWR group (37.1 mm) than in the ESD group (25.8 mm, P = 0.041). For patients with tumors smaller than 20 mm, ESD was associated with shorter mean operation time (89.7 ± 23.5 vs 117.6 ± 23.7 min, P = 0.043), less blood loss (4.9 ± 1.7 vs 72.3 ± 23.3 ml, P < 0.001), shorter length of hospital stay (3.6 ± 1.9 vs 6.9 ± 3.7 days, P = 0.024) and lower cost (2471 ± 573 vs 4498 ± 1257 dollars, P = 0.031) when compared with LWR. For patients with tumors between 20 mm and 50 mm, ESD was associated with shorter mean operation time (99.3 ± 27.8 vs 125.2 ± 31.5 min, P = 0.039), less blood loss (10.1 ± 5.3 vs 87.6 ± 31.3 ml, P < 0.001), shorter length of hospital stay (4.0 ± 1.7 vs 7.3 ± 4.5 days, P = 0.027) and lower cost (2783 ± 601 vs 4798 ± 1343 dollars, P = 0.033) when compared with LWR. There were no significant differences in terms of rates of en bloc resection, complete resection and complication and histological diagnosis regardless of tumor size. CONCLUSIONS: ESD can achieve similar oncological outcomes when compared with surgery for treatment of gastric SMT smaller than 50 mm.


Asunto(s)
Tumores del Estroma Gastrointestinal/cirugía , Músculo Liso/patología , Neoplasias Gástricas/cirugía , Estudios de Cohortes , Resección Endoscópica de la Mucosa/métodos , Femenino , Mucosa Gástrica/cirugía , Gastroscopía/métodos , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Resultado del Tratamiento
16.
Nanoscale ; 16(2): 887-902, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38105768

RESUMEN

Gram-negative sepsis has become a substantial and escalating global healthcare challenge due to the growing antibiotic resistance crisis and the sluggish development of new antibiotics. LL-37, a unique Cathelicidin species found in humans, exhibits a wide range of bioactive properties, including direct bactericidal effects, inflammation regulation, and LPS neutralization. KR-12, the smallest yet potent peptide fragment of LL-37, has been modified to create more effective antimicrobials. In this study, we designed two myristoylated derivatives of KR-12, referred to as Myr-KR-12N and Myr-KR-12C. These derivatives displayed remarkable ability to spontaneously assemble into nanoparticles when mixed with deionized water. Myristoylated KR-12 derivatives exhibited broad-spectrum and intensified bactericidal activity by disrupting bacterial cell membranes. In particular, Myr-KR-12N showed superior capability to rescue mice from lethal E. coli-induced sepsis in comparison with the conventional antibiotic meropenem. We also confirmed that the myristoylated KR-12 nanobiotic possesses significant LPS binding capacity and effectively reduces inflammation in vitro. In an in vivo context, Myr-KR-12N outperformed polymyxin B in rescuing mice from LPS-induced sepsis. Crucially, toxicological assessments revealed that neither Myr-KR-12N nor Myr-KR-12C nanobiotics induced meaningful hemolysis or caused damage to the liver and kidneys. Collectively, our study has yielded an innovative nanobiotic with dual capabilities of bactericidal action and LPS-neutralization, offering substantial promise for advancing the clinical translation of antimicrobial peptides and the development of novel antibiotics. This addresses the critical need for effective solutions to combat Gram-negative sepsis, a pressing global medical challenge.


Asunto(s)
Infecciones por Escherichia coli , Sepsis , Humanos , Animales , Ratones , Péptidos Catiónicos Antimicrobianos/farmacología , Péptidos Catiónicos Antimicrobianos/química , Lipopolisacáridos/química , Escherichia coli/metabolismo , Catelicidinas/química , Catelicidinas/metabolismo , Catelicidinas/farmacología , Bacterias , Sepsis/tratamiento farmacológico , Antibacterianos/química , Pruebas de Sensibilidad Microbiana
17.
Carbohydr Polym ; 332: 121933, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38431401

RESUMEN

Minimally invasive, efficient, and satisfactory treatment for irregular and lacunar bone defects is still a challenge. Alginate hydrogels serve as promising stem cell (SC) delivery systems for bone regeneration but are limited by low cellular viability, poor osteogenic differentiation, and insufficient mechanical support. Herein, we developed a BMSCs-laden mechanically reinforced bioactive sodium alginate composite hydrogel microspheres (BCHMs) system via a microfluidic method that possesses 1) a uniform size and good injectability to meet clinical bone defects with complex shapes, 2) high cellular viability maintenance and further osteogenic induction capacity, and 3) improved mechanical properties. As the main matrix, the sodium alginate hydrogel maintains the high viability of encapsulated BMSCs and efficient substance exchange. Enhanced mechanical properties and osteogenic differentiation of the BCHMs in vitro were observed with xonotlite (Ca6Si6O17(OH)2, CSH) nanowires incorporated. Furthermore, BCHMs with 12.5 % CSH were injected into rat femoral bone defects, and satisfactory in situ regeneration outcomes were observed. Overall, it is believed that BCHMs expand the application of polysaccharide science and provide a promising injectable bone substitute for minimally invasive bone repair.


Asunto(s)
Hidrogeles , Osteogénesis , Ratas , Animales , Hidrogeles/farmacología , Microesferas , Regeneración Ósea , Alginatos
18.
Artículo en Inglés | MEDLINE | ID: mdl-38949426

RESUMEN

Periodontitis, an inflammatory bone resorption disease associated with dental plaque, poses significant challenges for effective treatment. In this study, we developed Mino@ZIF-8 nanoparticles inspired by the periodontal microenvironment and the unique properties of zeolitic imidazolate framework 8, aiming to address the complex pathogenesis of periodontitis. Transcriptome analysis revealed the active engagement of Mino@ZIF-8 nanoparticles in innate and adaptive inflammatory host defense and cellular metabolic remodeling. Through sustained release of the anti-inflammatory and antibacterial agent minocycline hydrochloride (Mino) and the generation of Zn2+ with pro-antioxidant effects during degradation, Mino@ZIF-8 nanoparticles synergistically alleviate inflammation and oxidative damage. Notably, our study focuses on the pivotal role of zinc ions in mitochondrial oxidation protection. Under lipopolysaccharide (LPS) stimulation, periodontal ligament cells undergo a metabolic shift from oxidative phosphorylation (OXPHOS) to glycolysis, leading to reduced ATP production and increased reactive oxygen species levels. However, Zn2+ effectively rebalances the glycolysis-OXPHOS imbalance, restoring cellular bioenergetics, mitigating oxidative damage, rescuing impaired mitochondria, and suppressing inflammatory cytokine production through modulation of the AKT/GSK3ß/NRF2 pathway. This research not only presents a promising approach for periodontitis treatment but also offers novel therapeutic opportunities for zinc-containing materials, providing valuable insights into the design of biomaterials targeting cellular energy metabolism regulation.

19.
Environ Sci Process Impacts ; 25(12): 2031-2041, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-37842808

RESUMEN

The oxidation of pyrite (FeS2) not only adversely affects the environment, but also plays a critical role in the geochemical evolution of Fe and S elements. However, the oxidation rate of FeS2 is often controlled by its exposed crystal facets. Herein, the oxidation behaviors and mechanisms of naturally existing FeS2(100) and FeS2(210) crystals are investigated. The adsorption models of O2 on FeS2(100) and FeS2(210) facets are established, additionally, their corresponding surface energies, O2 adsorption sites and energies are also obtained using Density Functional Theory (DFT) calculations. These results suggest that the FeS2(210) facet more readily reacts with O2 because it has more unsaturated coordination of Fe atoms compared with the FeS2(100) facet. Moreover, electrochemical results such as EIS, Tafel and CV curves further prove that FeS2(210) possesses a higher oxidation rate than that of FeS2(100). The results of chemical oxidation experiments and XPS analyses show that FeS2(210) can produce more total Fe, SO42- and H+ than FeS2(100). Furthermore, various intermediate S species such as SO32-, S2O32-, S3O62-, S4O62- and S5O62- are also detected. This work can provide a basis for understanding the oxidation mechanism of facet-dependent FeS2 and the geochemical evolution of Fe and S elements.


Asunto(s)
Hierro , Sulfuros , Hierro/química , Oxidación-Reducción , Sulfuros/química , Azufre/química
20.
Int J Biol Macromol ; 226: 1079-1087, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36436595

RESUMEN

Bone defects cause serious psychological and economic burden to patients. Artificially bone repairing materials bring hope to the treatment of bone defects. Electrospun technique has attracted great attention since it can fabricate fibers from nano- to micro- scale continuously. Scaffolds fabricated by electrospun can mimic the structure of extracellular matrix which is beneficial to cell adhesion and migration. Researches have showed that bioactive ions (such as silicon and calcium ions) can promote bone regeneration. In addition, physical cues can affect cellular behavior such as cell adhesion and differentiation. In this study, two kinds of calcium silicate - adopted poly (L-lactic acid) (CS-PLLA) electrospun scaffolds with random/aligned structures were prepared by electrospun to promote bone regeneration. The integration of CS nanowires improved the biological property of PLLA electrospun scaffolds. Furthermore, in vitro results indicated that aligned 1 wt% CS adopted PLLA (PCA1) electrospun scaffolds with better physical properties and facilitated cell adhesion, improved alkaline phosphate (ALP) activity and the expression of osteogenic genes (Osteopontin (OPN), Collagen type 1 (Col-1) and Bone morphogenetic protein-2 (BMP-2)) compared with random 1 wt% CS adopted PLLA (PCR1) electrospun scaffolds. In conclusion, the prepared PCA1 electrospun scaffolds might be a potential candidate for bone regeneration in defect areas.


Asunto(s)
Nanofibras , Nanocables , Humanos , Osteogénesis , Nanofibras/química , Poliésteres/química , Diferenciación Celular , Andamios del Tejido/química , Ingeniería de Tejidos , Proliferación Celular
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