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1.
Proc Natl Acad Sci U S A ; 118(48)2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34810252

RESUMO

Vascular endothelial cells are exposed to shear stresses with disturbed vs. laminar flow patterns, which lead to proinflammatory vs. antiinflammatory phenotypes, respectively. Effective treatment against endothelial inflammation and the consequent atherogenesis requires the identification of new therapeutic molecules and the development of drugs targeting these molecules. Using Connectivity Map, we have identified vitexin, a natural flavonoid, as a compound that evokes the gene-expression changes caused by pulsatile shear, which mimics laminar flow with a clear direction, vs. oscillatory shear (OS), which mimics disturbed flow without a clear direction. Treatment with vitexin suppressed the endothelial inflammation induced by OS or tumor necrosis factor-α. Administration of vitexin to mice subjected to carotid partial ligation blocked the disturbed flow-induced endothelial inflammation and neointimal formation. In hyperlipidemic mice, treatment with vitexin ameliorated atherosclerosis. Using SuperPred, we predicted that apurinic/apyrimidinic endonuclease1 (APEX1) may directly interact with vitexin, and we experimentally verified their physical interactions. OS induced APEX1 nuclear translocation, which was inhibited by vitexin. OS promoted the binding of acetyltransferase p300 to APEX1, leading to its acetylation and nuclear translocation. Functionally, knocking down APEX1 with siRNA reversed the OS-induced proinflammatory phenotype, suggesting that APEX1 promotes inflammation by orchestrating the NF-κB pathway. Animal experiments with the partial ligation model indicated that overexpression of APEX1 negated the action of vitexin against endothelial inflammation, and that endothelial-specific deletion of APEX1 ameliorated atherogenesis. We thus propose targeting APEX1 with vitexin as a potential therapeutic strategy to alleviate atherosclerosis.


Assuntos
Apigenina/genética , Apigenina/fisiologia , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Células Endoteliais/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Aterosclerose , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação , Camundongos , Fenótipo , Fosforilação , Ligação Proteica , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Transcrição de p300-CBP/metabolismo
2.
Proc Natl Acad Sci U S A ; 114(31): 8271-8276, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28716920

RESUMO

Vascular endothelial cells (ECs) at arterial branches and curvatures experience disturbed blood flow and induce a quiescent-to-activated phenotypic transition of the adjacent smooth muscle cells (SMCs) and a subsequent smooth muscle hyperplasia. However, the mechanism underlying the flow pattern-specific initiation of EC-to-SMC signaling remains elusive. Our previous study demonstrated that endothelial microRNA-126-3p (miR-126-3p) acts as a key intercellular molecule to increase turnover of the recipient SMCs, and that its release is reduced by atheroprotective laminar shear (12 dynes/cm2) to ECs. Here we provide evidence that atherogenic oscillatory shear (0.5 ± 4 dynes/cm2), but not atheroprotective pulsatile shear (12 ± 4 dynes/cm2), increases the endothelial secretion of nonmembrane-bound miR-126-3p and other microRNAs (miRNAs) via the activation of SNAREs, vesicle-associated membrane protein 3 (VAMP3) and synaptosomal-associated protein 23 (SNAP23). Knockdown of VAMP3 and SNAP23 reduces endothelial secretion of miR-126-3p and miR-200a-3p, as well as the proliferation, migration, and suppression of contractile markers in SMCs caused by EC-coculture. Pharmacological intervention of mammalian target of rapamycin complex 1 in ECs blocks endothelial secretion and EC-to-SMC transfer of miR-126-3p through transcriptional inhibition of VAMP3 and SNAP23. Systemic inhibition of VAMP3 and SNAP23 by rapamycin or periadventitial application of the endocytosis inhibitor dynasore ameliorates the disturbed flow-induced neointimal formation, whereas intraluminal overexpression of SNAP23 aggravates it. Our findings demonstrate the flow-pattern-specificity of SNARE activation and its contribution to the miRNA-mediated EC-SMC communication.


Assuntos
Hiperplasia/patologia , MicroRNAs/metabolismo , Músculo Liso Vascular/citologia , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Proteína 3 Associada à Membrana da Vesícula/metabolismo , Animais , Células Endoteliais/fisiologia , Humanos , Camundongos , Camundongos Knockout , MicroRNAs/genética , Miócitos de Músculo Liso/fisiologia , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Proteínas SNARE/metabolismo , Proteína 3 Associada à Membrana da Vesícula/genética
3.
J Mol Cell Cardiol ; 128: 11-24, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659837

RESUMO

Macrophage-mediated inflammatory responses occur throughout all stages of atherosclerosis. DNA methylation is one of the critical epigenetic mechanisms and is associated with the development of atherosclerosis. The underlying mechanism of epigenetic regulation of macrophage inflammation (M1 activation) remains unclear. Here we aim to study the role of DNA methyltransferase 1 (DNMT1) in modulating macrophage inflammation and atherosclerosis. DNMT1 expression is up-regulated in THP-1-derived macrophages upon treatment with lipopolysaccharide (LPS) and interferon-gamma (IFN-γ). Overexpression of DNMT1 promotes the LPS- and IFN-γ-induced M1 activation whereas inhibition of DNMT1 attenuates it. Consistently, DNMT1 expression is elevated in macrophages in atherosclerotic plaques from human and mouse specimens; compared with the Dnmt1wild-type, myeloid Dnmt1 deficiency in mice in an Apolipoprotein E (ApoE) knockout background or receiving AAV-PSCK9 injection and carotid partial ligation results in ameliorated atheroma formation and suppressed plaque inflammation. The promoter regions of atheroprotective Krüppel-like factor 4 (KLF4) are hypermethylated in M1- activated macrophages. DNMT1 down-regulates the expression of KLF4, probably through catalyzing DNA methylation of the promoter regions of KLF4. Gain- and loss-of function study of KLF4 indicates that the DNMT1-mediated macrophage M1 activation is dependent on KLF4. Our data demonstrate a proatherogenic role for DNMT1 as a defining factor in macrophage inflammation both in vitro and in vivo. DNMT1 promotes macrophage M1 activation by suppressing KLF4 expression. Thus macrophage-specific DNMT1 inhibition may provide an attractive therapeutic potential to prevent or reduce atherosclerosis.


Assuntos
Aterosclerose/genética , DNA (Citosina-5-)-Metiltransferase 1/genética , Inflamação/genética , Fatores de Transcrição Kruppel-Like/genética , Animais , Apolipoproteínas E/genética , Aterosclerose/patologia , Metilação de DNA/genética , Epigênese Genética , Regulação da Expressão Gênica/genética , Humanos , Inflamação/patologia , Interferon gama/genética , Fator 4 Semelhante a Kruppel , Lipopolissacarídeos/farmacologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Mutação , Regiões Promotoras Genéticas/genética
4.
Eur Spine J ; 26(7): 1826-1832, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27435486

RESUMO

PURPOSE: To evaluate whether acetabular orientation (abduction and anteversion) can be restored by lumbar pedicle subtraction osteotomy (PSO) in ankylosing spondylitis (AS) patients with thoracolumbar kyphosis. MATERIALS AND METHODS: A total of 33 consecutive AS patients with thoracolumbar kyphosis undergoing one-level lumbar PSO were retrospectively reviewed. Radiographical measurements included sagittal vertical axis, global kyphosis, thoracic kyphosis, local kyphosis, lumbar lordosis, pelvic incidence, sacral slope, and pelvic tilt. Acetabular abduction and anteversion were measured on CT scans of the pelvis before and after lumbar PSO. The preoperative and postoperative parameters were compared by the paired samples t test. Pearson's correlation analysis was conducted to determine the correlations between the changes in acetabular abduction and anteversion and the changes in sagittal spinopelvic parameters. RESULTS: After lumbar PSO, sagittal vertical axis, global kyphosis, and pelvic tilt were corrected from 15.7 ± 6.7 cm, 66.8° ± 17.5°, and 38.6° ± 9.0° to 2.9 ± 4.9 cm, 21.3° ± 8.2°, and 23.2° ± 8.2°, respectively (p < 0.001). Of note, acetabular abduction and anteversion decreased from 59.6° ± 4.6° to 31.4° ± 6.5° before surgery to 51.4° ± 6.5° and 20.2° ± 4.4° after surgery, respectively (p < 0.001). Moreover, the changes in acetabular abduction and anteversion were observed significantly correlated with the change in pelvic tilt (r = 0.527, p = 0.002; r = 0.586, p < 0.001). CONCLUSION: Abnormal acetabular abduction and anteversion could be corrected by lumbar PSO in AS patients with thoracolumbar kyphosis. Consequently, a relatively normal acetabular orientation could be achieved after lumbar PSO, which might decrease the potential risk of dislocation in AS patients with spine and hip deformities requiring subsequent THR surgery.


Assuntos
Acetábulo , Mau Alinhamento Ósseo/cirurgia , Cifose/cirurgia , Vértebras Lombares/cirurgia , Osteotomia/métodos , Espondilite Anquilosante/complicações , Acetábulo/diagnóstico por imagem , Adolescente , Adulto , Idoso , Mau Alinhamento Ósseo/diagnóstico por imagem , Mau Alinhamento Ósseo/etiologia , Feminino , Seguimentos , Humanos , Cifose/diagnóstico por imagem , Cifose/etiologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Espondilite Anquilosante/diagnóstico por imagem , Espondilite Anquilosante/cirurgia , Vértebras Torácicas/diagnóstico por imagem , Adulto Jovem
5.
Iran J Basic Med Sci ; 27(6): 671-677, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645498

RESUMO

Objectives: Wnt5a, which regulates the activities of osteoblasts and osteoclasts, is reportedly overexpressed in osteoarthritis (OA) tissues. The purpose of this study was to elucidate its role in the development of OA by deleting Wnt5a in osteocalcin (OCN)-expressing cells. Materials and Methods: Knee OA was induced by anterior cruciate ligament transection (ACLT) in OCN-Cre;Wnt5afl/fl knockout (Wnt5a-cKO) mice and control littermates. Eight weeks after surgery, histological changes, cell apoptosis, and matrix metabolism of cartilage were evaluated by toluidine blue, TUNEL staining, and im-immunohistochemistry analyses, respectively. In addition, the subchondral bone microarchitecture of mice was examined by micro-computed tomography (micro-CT). Results: Histological scores show substantial cartilage degeneration occurred in ACLT knees, coupled with decreased collagen type II expression and enhanced matrix metalloproteinase 13 expression, as well as higher proportions of apoptotic cells. Micro-CT results show that ACLT resulted in decreased bone mineral density, bone volume/trabecular volume, trabecular number, and structure model index of subchondral bones in both Wnt5a-cKO and control littermates; although Wnt5a-cKO mice display lower BMD and BV/TV values, no significant difference was observed between Wnt5a-cKO and control mice for any of these values. Conclusion: Our findings indicate that Wnt5a deficiency in OCN-expressing cells could not prevent an osteoarthritic phenotype in a mouse model of post-traumatic OA.

6.
Nucleic Acids Res ; 39(3): 825-36, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20929877

RESUMO

Synergistic regulations among multiple microRNAs (miRNAs) are important to understand the mechanisms of complex post-transcriptional regulations in humans. Complex diseases are affected by several miRNAs rather than a single miRNA. So, it is a challenge to identify miRNA synergism and thereby further determine miRNA functions at a system-wide level and investigate disease miRNA features in the miRNA-miRNA synergistic network from a new view. Here, we constructed a miRNA-miRNA functional synergistic network (MFSN) via co-regulating functional modules that have three features: common targets of corresponding miRNA pairs, enriched in the same gene ontology category and close proximity in the protein interaction network. Predicted miRNA synergism is validated by significantly high co-expression of functional modules and significantly negative regulation to functional modules. We found that the MFSN exhibits a scale free, small world and modular architecture. Furthermore, the topological features of disease miRNAs in the MFSN are distinct from non-disease miRNAs. They have more synergism, indicating their higher complexity of functions and are the global central cores of the MFSN. In addition, miRNAs associated with the same disease are close to each other. The structure of the MFSN and the features of disease miRNAs are validated to be robust using different miRNA target data sets.


Assuntos
Doença/genética , Redes Reguladoras de Genes , MicroRNAs/metabolismo , Algoritmos , Humanos , Interferência de RNA
7.
Viruses ; 15(2)2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36851535

RESUMO

The Omicron variant is currently ravaging the world, raising serious concern globally. Monitoring genomic variations and determining their influence on biological features are critical for tracing its ongoing transmission and facilitating effective measures. Based on large-scale sequences from different continents, this study found that: (i) The genetic diversity of Omicron is much lower than that of the Delta variant. Still, eight deletions (Del 1-8) and 1 insertion, as well as 130 SNPs, were detected on the Omicron genomes, with two deletions (Del 3 and 4) and 38 SNPs commonly detected on all continents and exhibiting high-occurring frequencies. (ii) Four groups of tightly linked SNPs (linkage I-IV) were detected, among which linkage I, containing 38 SNPs, with 6 located in the RBD, increased its occurring frequency remarkably over time. (iii) The third codons of the Omicron shouldered the most mutation pressures, while the second codons presented the least flexibility. (iv) Four major mutants with amino acid substitutions in the RBD were detected, and further structural analysis suggested that the substitutions did not alter the viral receptor binding ability greatly. It was inferred that though the Omicron genome harbored great changes in antigenicity and remarkable ability to evade immunity, it was immune-pressure selected. This study tracked mutational signatures of Omicron variant and the potential biological significance of the SNPs, and the linkages await further functional verification.


Assuntos
COVID-19 , Humanos , SARS-CoV-2/genética , Mutação , Substituição de Aminoácidos
8.
Aging (Albany NY) ; 12(10): 9549-9584, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32454462

RESUMO

BACKGROUND: Stearoyl-coenzyme A desaturase-1 (SCD1) can inhibit the development of diabetic bone disease by promoting osteogenesis. In this study, we examined whether this regulation by SCD1 is achieved by regulating the expression of related miRNAs. METHODS: SCD1 expression levels were observed in human bone-marrow mesenchymal stem cells (BM-MSCs) of patients with type 2 diabetes mellitus (T2DM), and the effect of SCD1 on osteogenesis was observed in human adipose-derived MSCs transfected with the SCD1 lentiviral system. We designed a bioinformatics prediction model to select important differentially expressed miRNAs, and established protein-protein interaction and miRNA-mRNA networks. miRNAs and mRNAs were extracted and their differential expression was detected. The SCD1-miRNA-mRNA network was validated. FINDINGS: SCD1 expression in bone marrow was downregulated in patients with T2DM and low-energy fracture, and SCD1 expression promotes BM-MSC osteogenic differentiation. The predictors in the nomogram were seven microRNAs, including hsa-miR-1908 and hsa-miR-203a. SCD1 inhibited the expression of CDKN1A and FOS, but promoted the expression of EXO1 and PLS1. miR-1908 was a regulator of EXO1 expression, and miR-203a was a regulator of FOS expression. INTERPRETATION: The regulation of BM-MSCs by SCD1 is a necessary condition for osteogenesis through the miR-203a/FOS and miR-1908/EXO1 regulatory pathways.


Assuntos
Diabetes Mellitus Tipo 2/genética , Fraturas Ósseas/genética , MicroRNAs/metabolismo , Pós-Menopausa/genética , Estearoil-CoA Dessaturase/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Regulação para Baixo/genética , Exodesoxirribonucleases/metabolismo , Feminino , Marcadores Genéticos/genética , Humanos , Células-Tronco Mesenquimais/metabolismo , Nomogramas , Proteínas Proto-Oncogênicas c-fos/metabolismo , Medição de Risco/métodos , Fatores de Risco
9.
ACS Appl Mater Interfaces ; 12(47): 53230-53238, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33179903

RESUMO

Conductive textiles (CTs) are promising electromagnetic interference (EMI) shielding materials. Nevertheless, limited stretchability and poor reliability restrict their potential applications in stretchable electronic devices because of the rigid conductive networks. Herein, a highly stretchable and reliable CT is developed for effective EMI shielding by designing a deformable liquid-metal (LM) coating and polydimethylsiloxane (PDMS) protective layer. The resultant PDMS-LM/Textile exhibits an outstanding EMI shielding efficiency (EMI SE) of 72.6 dB at a thickness of only 0.35 mm while maintaining EMI SEs of 66.0 and 52.4 dB under strains of 30 and 50%, respectively. The corresponding EMI SEs hold 91.7 and 80.3% retention after 5000 stretching-releasing cycles, respectively. The superior and durable EMI SE should be ascribed to the perfect connectivity and good deformability of conductive LM networks. Moreover, the LM coating has a robust fastness to the textile substrate, without any obvious decrease in EMI SE after 10 min of ultrasonic treatment and 100 peeling cycles because of the protective effect of the PDMS layer. This work provides a novel route to developing highly stretchable CTs for advanced EMI shielding applications, especially in the field of highly stretchable electronic devices.

10.
PeerJ ; 8: e8793, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328345

RESUMO

PURPOSE: To develop a risk prediction model for postoperative sarcopenia in elderly patients with patellar fractures in China. PATIENTS AND METHODS: We conducted a community survey of patients aged ≥55 years who underwent surgery for patellar fractures between January 2013 and October 2018, through telephone interviews, community visits, and outpatient follow-up. We established a predictive model for assessing the risk of sarcopenia after patellar fractures. We developed the prediction model by combining multivariate logistic regression analysis with the least absolute shrinkage model and selection operator regression (lasso analysis) as well as the Support Vector Machine (SVM) algorithm. The predictive quality and clinical utility of the predictive model were determined using C-index, calibration plots, and decision curve analysis. We also conducted internal sampling methods for qualitative assessment. RESULT: We recruited 137 participants (53 male; mean age, 65.7 years). Various risk factors were assessed, and low body mass index and advanced age were identified as the most important risk factor (P < 0.05). The prediction rate of the model was good (C-index: 0.88; 95% CI [0.80552-0.95448]), with a satisfactory correction effect. The C index is 0.97 in the validation queue and 0.894 in the entire cohort. Decision curve analysis suggested good clinical practicability. CONCLUSION: Our prediction model shows promise as a cost-effective tool for predicting the risk of postoperative sarcopenia in elderly patients based on the following: advanced age, low body mass index, diabetes, less outdoor exercise, no postoperative rehabilitation, different surgical methods, diabetes, open fracture, and removal of internal fixation.

11.
Cell Death Dis ; 11(1): 35, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959742

RESUMO

Vascular smooth muscle cell (SMC) from arterial stenotic-occlusive diseases is featured with deficiency in mitochondrial respiration and loss of cell contractility. However, the regulatory mechanism of mitochondrial genes and mitochondrial energy metabolism in SMC remains elusive. Here, we described that DNA methyltransferase 1 (DNMT1) translocated to the mitochondria and catalyzed D-loop methylation of mitochondrial DNA in vascular SMCs in response to platelet-derived growth factor-BB (PDGF-BB). Mitochondrial-specific expression of DNMT1 repressed mitochondrial gene expression, caused functional damage, and reduced SMC contractility. Hypermethylation of mitochondrial D-loop regions were detected in the intima-media layer of mouse carotid arteries subjected to either cessation of blood flow or mechanical endothelial injury, and also in vessel specimens from patients with carotid occlusive diseases. Likewise, the ligated mouse arteries exhibited an enhanced mitochondrial binding of DNMT1, repressed mitochondrial gene expression, defects in mitochondrial respiration, and impaired contractility. The impaired contractility of a ligated vessel could be restored by ex vivo transplantation of DNMT1-deleted mitochondria. In summary, we discovered the function of DNMT1-mediated mitochondrial D-loop methylation in the regulation of mitochondrial gene transcription. Methylation of mitochondrial D-loop in vascular SMCs contributes to impaired mitochondrial function and loss of contractile phenotype in vascular occlusive disease.


Assuntos
Metilação de DNA/genética , DNA Mitocondrial/genética , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Animais , Becaplermina/farmacologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Respiração Celular/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Doenças Vasculares/genética , Doenças Vasculares/patologia
12.
Shanghai Kou Qiang Yi Xue ; 28(4): 356-361, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31792473

RESUMO

PURPOSE: To explore the effect of rutin on osteogenic differentiation of periodontal ligament stem cells under inflammatory microenvironment. METHODS: Periodontal ligament stem cells (PDLSCs) were obtained by limited dilution method in vitro. PDLSCs were identified by flow cytometery. Lipopolysaccharide(LPS) was used to stimulate human periodontal ligament stem cells to establish an inflammation model in vitro. The experiment was divided into 4 groups: in group 1, only α-MEM was used to culture PDLSCs; in group 2, α-MEM medium containing LPS was used to culture PDLSCs, in group 3, rutin was added to α-MEM medium containing LPS to PDLSCs; and in group 4, α-MEM medium containing rutin was used to culture PDLSCs. Cell counting kit-8 was used to detect cell proliferation activity. Alkaline phosphatase(ALP) staining, ALP activity test, alizarin red staining, RT-PCR, and Western blot were used to detect the changes of osteogenic differentiation ability. The data were analyzed by SPSS 17.0 software package. RESULTS: The results of CCK-8 and ALP activity analysis showed that rutin at 10 µmol/L could significantly promote the proliferation and differentiation of periodontal stem cells under inflammatory state. ALP staining and alizarin red staining proved that (10 µmol/L) rutin could improve osteogenic differentiation of periodontal ligament stem cells under inflammatory microenvironment. RT-PCR and Western blot results showed that rutin could enhance the expression of osteogenic genes and proteins such as COL1, ALP, and RUNX2 under inflammatory state. CONCLUSIONS: Rutin can promote osteogenic differentiation of periodontal ligament stem cells under inflammatory microenvironment.


Assuntos
Osteogênese , Ligamento Periodontal , Fosfatase Alcalina , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Humanos , Rutina , Células-Tronco
13.
World Neurosurg ; 116: e850-e855, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29807178

RESUMO

OBJECTIVE: To evaluate the accuracy and safety of freehand pedicle screw placement in surgical correction for thoracolumbar kyphosis caused by ankylosing spondylitis (AS). METHODS: We retrospectively reviewed 266 consecutive patients with AS who underwent osteotomy for kyphosis correction with freehand screw insertion from January 1998 to April 2015 at our institution. A total of 2314 pedicle screws in 158 patients with AS with postoperative computed tomography scans were included in the study. Postoperative computed tomography was performed to classify accuracy of screws, using the established Gertbein classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation between 2 and 4 mm, and grade 3: perforation >4 mm). Patients were divided into 2 groups according to coronal Cobb angle: group A (n = 21, Cobb angle ≥10°), group B (n = 137, Cobb angle <10°). RESULTS: Among the 2314 pedicle screws, 2168 pedicle screw placements were categorized as grade 0, 71 were grade 1, 51 were grade 2, and 24 were grade 3. Breaches occurred more frequently in L1-S1 than the thoracic spine (7.1% and 5.4%, respectively). T5 (25.0%) and S1 (17.7%) experienced the greatest breach rate, whereas T8, L1, and L3 had the lowest breach rate. The breach rate of group A was greater than that of group B (7.9% vs. 6.1%). None of the breaches resulted in either neurologic deficits or vascular complications. CONCLUSIONS: Freehand pedicle screw placement can be performed safely with acceptable breach rate in patients with AS and thoracolumbar kyphosis.


Assuntos
Cifose/cirurgia , Vértebras Lombares/cirurgia , Parafusos Pediculares/normas , Espondilite Anquilosante/cirurgia , Vértebras Torácicas/cirurgia , Tomografia Computadorizada por Raios X/normas , Adolescente , Adulto , Feminino , Humanos , Cifose/diagnóstico por imagem , Cifose/etiologia , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Osteotomia/instrumentação , Osteotomia/normas , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/normas , Estudos Retrospectivos , Espondilite Anquilosante/complicações , Espondilite Anquilosante/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
14.
Biomaterials ; 155: 203-216, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29182961

RESUMO

Cells perceive the physical cues such as perturbations of extracellular matrix (ECM) stiffness, and translate these stimuli into biochemical signals controlling various aspects of cell behavior, which contribute to the physiological and pathological processes of multiple organs. In this study, we tested the hypothesis that during arterial stiffening, vascular smooth muscle cells (SMCs) sense the increase of ECM stiffness, which modulates the cellular phenotype through the regulation in DNA methyltransferases 1 (DNMT1) expression. Moreover, we hypothesized that the mechanisms involve intrinsic stiffening and deficiency in contractility of vascular SMCs. Substrate stiffening was mimicked in vitro with polyacrylamide gels. A contractile-to-synthetic phenotypic transition was induced by substrate stiffening in vascular SMCs through the down-regulation of DNMT1 expression. DNMT1 repression was also observed in the tunica media of mice aortas in an acute aortic injury model and a chronic kidney failure model, as well as in the tunica intima of human carotid arteries with calcified atherosclerotic lesions. DNMT1 inhibition facilitates arterial stiffening in vivo and promotes osteogenic transdifferentiation, calcification and cellular stiffening of vascular SMCs in vitro. These effects may be attributable, at least in part, to the role of DNMT1 in regulating the promoter activities of Transgelin (SM22α) and α-smooth muscle actin (SMA) and the functional contractility of SMCs. We conclude that DNMT1 is a critical regulator that negatively regulates arterial stiffening via maintaining the contractile phenotype of vascular SMCs. This research may facilitate elucidation of the complex crosstalk between vascular SMCs and their surrounding matrix in healthy and in pathological conditions and provide new insights into the implications for potential targeting of the phenotypic regulatory mechanisms in material-related therapeutic applications.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/metabolismo , Actinas/metabolismo , Animais , Metilação de DNA/fisiologia , Matriz Extracelular/metabolismo , Camundongos , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Rigidez Vascular/fisiologia
15.
Front Pharmacol ; 9: 346, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29755345

RESUMO

The analogous ß-carboline alkaloids, harmaline (HAL) and harmine (HAR), possess a variety of biological properties, including acetylcholinesterase (AChE) inhibitory activity, antioxidant, anti-inflammatory, and many others, and have great potential for treating Alzheimer's disease (AD). However, studies have showed that the two compounds have similar structures and in vitro AChE inhibitory activities but with significant difference in bioavailability. The objective of this study was to comparatively investigate the effects of HAL and HAR in memory deficits of scopolamine-induced mice. In the present study, mice were pretreated with HAL (2, 5, and 10 mg/kg), HAR (10, 20, and 30 mg/kg) and donepezil (5 mg/kg) by intragastrically for 7 days, and were daily intraperitoneal injected with scopolamine (1 mg/kg) to induce memory deficits and then subjected to behavioral evaluation by Morris water maze. To further elucidate the underlying mechanisms of HAL and HAR in improving learning and memory, the levels of various biochemical factors and protein expressions related to cholinergic function, oxidative stress, and inflammation were examined. The results showed that HAL and HAR could effectively ameliorate memory deficits in scopolamine-induced mice. Both of them exhibited an enhancement in cholinergic function by inhibiting AChE and inducing choline acetyltransferase (ChAT) activities, and antioxidant defense via increasing the antioxidant enzymes activities of superoxide dismutase and glutathione peroxidase, and reducing maleic diadehyde production, and anti-inflammatory effects through suppressing myeloperoxidase, tumor necrosis factor α, and nitric oxide as well as modulation of critical neurotransmitters such as acetylcholine (ACh), choline (Ch), L-tryptophan (L-Trp), 5-hydroxytryptamine (5-HT), γ-aminobutyric acid (γ-GABA), and L-glutamic acid (L-Glu). Furthermore, the regulations of HAL on cholinergic function, inflammation, and neurotransmitters were more striking than those of HAR, and HAL manifested a comparable antioxidant capacity to HAR. Remarkably, the effective dosage of HAL (2 mg/kg) was far lower than that of HAR (20 mg/kg), which probably due to the evidently differences in the bioavailability and metabolic stability of the two analogs. Taken together, all these results revealed that HAL may be a promising candidate compound with better anti-amnesic effects and pharmacokinetic characteristics for the treatments of AD and related diseases.

16.
Org Lett ; 9(1): 117-20, 2007 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-17192099

RESUMO

[reaction: see text] The choice of Lewis acid catalyst can result in dramatic differences in the chemoselectivity of the rearrangement reactions of vinylcyclopropenes. When BF3.OEt2 was used as the catalyst, naphthalenes were formed. However, when Cu(OTf)2 was used as the catalyst, indenes were obtained.

17.
Clin Spine Surg ; 30(7): E871-E876, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27841801

RESUMO

STUDY DESIGN: This is a retrospective study. OBJECTIVE: To identify the relationship between global sagittal alignment and health-related quality of life (HRQoL) in ankylosing spondylitis (AS) patients with thoracolumbar kyphosis. SUMMARY OF BACKGROUND DATA: Little data are available on correlation between global sagittal alignment and HRQoL in AS. MATERIALS AND METHODS: A total of 107 AS patients were included in this study. The radiographic parameters were measured on lateral radiographs of the whole spine, including sagittal vertical axias (SVA), spinosacral angle (SSA), spinopelvic angle (SPA), and T1 pelvic angle (TPA). HRQoL was assessed using the oswestry disability index questionnaire, the bath ankylosing spondylitis disease activity index, the bath ankylosing spondylitis functional index, and short form-36 questionnaire. The patients were divided into 2 groups: group A (n=76, global kyphosis≤70 degrees), group B (n=31, global kyphosis>70 degrees). Statistical analysis was performed to identify significant differences between these 2 groups. In addition, correlation analysis and multiple regression analysis between radiologic parameters and clinical questionnaires were conducted. RESULTS: With respect to SVA, SSA, SPA, TPA, and HRQoL scores, significant differences were observed between 2 groups (P<0.05). Also, SVA, SSA, SPA, and TPA were significantly related to HRQoL. Multiple regression analysis revealed that SVA, SSA, SPA, and TPA were significant parameters in the prediction of HRQoL in AS patients with thoracolumbar kyphosis. Of note, HRQoL related much more to SSA and SPA than SVA and TPA. CONCLUSIONS: AS patients with moderate and severe deformity were demonstrated to be significantly different in terms of SVA, SSA, SPA, TPA, and HRQoL. Moreover, SVA, SSA, SPA, and TPA correlated with HRQoL significantly. In particular, SSA and SPA could better predict HRQoL than SVA and TPA in AS patients with thoracolumbar kyphosis.


Assuntos
Cifose/fisiopatologia , Vértebras Lombares/fisiopatologia , Pelve/fisiopatologia , Qualidade de Vida , Sacro/fisiopatologia , Espondilite Anquilosante/fisiopatologia , Vértebras Torácicas/fisiopatologia , Adolescente , Adulto , Idoso , Fenômenos Biomecânicos , Demografia , Feminino , Humanos , Cifose/complicações , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Espondilite Anquilosante/complicações , Adulto Jovem
18.
Medicine (Baltimore) ; 96(6): e5963, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28178137

RESUMO

To date, only a few reports described the potential factors influencing the position of conus medullaris. One previous study revealed no significant change of conus locations in patients with idiopathic scoliosis; however, the effect of ankylosing spondylitis (AS)-related thoracolumbar kyphosis on conus position remains unexplored. Therefore, we aimed to investigate the variation of conus medullaris terminations in patients with thoracolumbar kyphosis secondary to AS when compared with normal subjects, and evaluated the relationship between conus positions and the magnitude of kyphosis. In this study, MR images of 96 AS patients with thoracolumbar kyphosis, including 86 males and 10 females with an average of 34.6 years (range, 17-65 years), and 100 age-matched normal controls were reviewed to determine the conus terminations in relation to spinal levels. Sagittal parameters of the AS group measured on radiograph included: global kyphosis (GK), thoracic kyphosis (TK), lumbar lordosis (LL), and thoracolumbar junction (TLJ). Finally, conus tips located at the mean level of the lower 3rd of L1 in both groups, there was no significant difference of the conus distributions between AS and control group (P = 0.49). In addition, conus medullaris displayed similar positions in AS patients among various apical region groups (P = 0.88), and no significant difference was found when AS population was stratified into GK ranges of 30° (P = 0.173). Also, no remarkable correlation of the conus positions with GK (r = -0.15, P = 0.15), TK (r = -0.10, P = 0.34), LL (r = -0.10, P = 0.32), and TLJ (r = -0.06, P = 0.54) was identified. This study showed the conus terminations displayed a wide range of distributions in AS patients with thoracolumbar kyphosis, which was similar to normal subjects. Moreover, the conus located at a relatively fixed position and would not be affected by the change of kyphosis magnitude, which is an important knowledge that surgeons should acquire in surgical correction of the deformity in these patients.


Assuntos
Cifose/patologia , Medula Espinal/patologia , Espondilite Anquilosante/patologia , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Cifose/etiologia , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Espondilite Anquilosante/complicações , Vértebras Torácicas/patologia , Adulto Jovem
19.
Sci Rep ; 7(1): 15322, 2017 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-29127397

RESUMO

MicroRNAs (miRNAs) regulate biological pathways by inhibiting gene expression. However, most current analytical methods fail to consider miRNAs, when inferring functional or pathway activities. In this study, we developed a model called sPAGM to infer subpathway activities by integrating gene and miRNA expressions. In this model, we reconstructed subpathway graphs by embedding miRNA components, and characterized subpathway activity (sPA) scores by simultaneously considering the expression levels of miRNAs and genes. The results showed that the sPA scores could distinguish different samples across tumor types, as well as samples between tumor and normal conditions. Moreover, the sPAGM model displayed more specificities than the entire pathway-based analyses. This model was applied to melanoma tumors to perform a prognosis analysis, which identified a robust 55-subpathway signature. By using The Cancer Genome Atlas and independently verified data sets, the subpathway-based signature significantly predicted the patients' prognoses, which were independent of clinical variables. In the prognostic performance comparison, the sPAGM model was superior to the gene-only and miRNA-only methods. Finally, we dissected the functional roles and interactions of components within the subpathway signature. Taken together, the sPAGM model provided a framework for inferring subpathway activities and identifying functional signatures for clinical applications.


Assuntos
Bases de Dados de Ácidos Nucleicos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Melanoma/metabolismo , MicroRNAs/biossíntese , RNA Neoplásico/biossíntese , Neoplasias Cutâneas/metabolismo , Feminino , Humanos , Masculino , Melanoma/genética , Melanoma/patologia , MicroRNAs/genética , RNA Neoplásico/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
20.
Sci Rep ; 7(1): 14996, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29118325

RESUMO

The earliest atherosclerotic lesions preferentially develop in arterial regions experienced disturbed blood flow, which induces endothelial expression of pro-atherogenic genes and the subsequent endothelial dysfunction. Our previous study has demonstrated an up-regulation of DNA methyltransferase 1 (DNMT1) and a global hypermethylation in vascular endothelium subjected to disturbed flow. Here, we determined that DNMT1-specific inhibition in arterial wall ameliorates the disturbed flow-induced atherosclerosis through, at least in part, targeting cell cycle regulator cyclin A and connective tissue growth factor (CTGF). We identified the signaling pathways mediating the flow-induction of DNMT1. Inhibition of the mammalian target of rapamycin (mTOR) suppressed the DNMT1 up-regulation both in vitro and in vivo. Together, our results demonstrate that disturbed flow influences endothelial function and induces atherosclerosis in an mTOR/DNMT1-dependent manner. The conclusions obtained from this study might facilitate further evaluation of the epigenetic regulation of endothelial function during the pathological development of atherosclerosis and offer novel prevention and therapeutic targets of this disease.


Assuntos
Aterosclerose/patologia , Endotélio Vascular/patologia , Epigênese Genética/fisiologia , Hemorreologia/fisiologia , Animais , Artérias/patologia , Artérias/fisiopatologia , Aterosclerose/genética , Aterosclerose/fisiopatologia , Bovinos , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Ciclina A/genética , Ciclina A/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Metilação de DNA/fisiologia , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Regiões Promotoras Genéticas/genética , Serina-Treonina Quinases TOR/metabolismo
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