Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 120(18): e2216342120, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-37098070

RESUMO

NKG2D (natural-killer group 2, member D) is a homodimeric transmembrane receptor that plays an important role in NK, γδ+, and CD8+ T cell-mediated immune responses to environmental stressors such as viral or bacterial infections and oxidative stress. However, aberrant NKG2D signaling has also been associated with chronic inflammatory and autoimmune diseases, and as such NKG2D is thought to be an attractive target for immune intervention. Here, we describe a comprehensive small-molecule hit identification strategy and two distinct series of protein-protein interaction inhibitors of NKG2D. Although the hits are chemically distinct, they share a unique allosteric mechanism of disrupting ligand binding by accessing a cryptic pocket and causing the two monomers of the NKG2D dimer to open apart and twist relative to one another. Leveraging a suite of biochemical and cell-based assays coupled with structure-based drug design, we established tractable structure-activity relationships with one of the chemical series and successfully improved both the potency and physicochemical properties. Together, we demonstrate that it is possible, albeit challenging, to disrupt the interaction between NKG2D and multiple protein ligands with a single molecule through allosteric modulation of the NKG2D receptor dimer/ligand interface.


Assuntos
Células Matadoras Naturais , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Ligantes , Linfócitos T CD8-Positivos , Ligação Proteica
2.
Bioorg Med Chem Lett ; 96: 129492, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37778428

RESUMO

Natural killer group 2D (NKG2D) is a homodimeric activating immunoreceptor whose function is to detect and eliminate compromised cells upon binding to the NKG2D ligands (NKG2DL) major histocompatibility complex (MHC) molecules class I-related chain A (MICA) and B (MICB) and UL16 binding proteins (ULBP1-6). While typically present at low levels in healthy cells and tissue, NKG2DL expression can be induced by viral infection, cellular stress or transformation. Aberrant activity along the NKG2D/NKG2DL axis has been associated with autoimmune diseases due to the increased expression of NKG2D ligands in human disease tissue, making NKG2D inhibitors an attractive target for immunomodulation. Herein we describe the discovery and optimization of small molecule PPI (protein-protein interaction) inhibitors of NKG2D/NKG2DL. Rapid SAR was guided by structure-based drug design and accomplished by iterative singleton and parallel medicinal chemistry synthesis. These efforts resulted in the identification of several potent analogs (14, 21, 30, 45) with functional activity and improved LLE.


Assuntos
Proteínas de Transporte , Subfamília K de Receptores Semelhantes a Lectina de Células NK , Humanos , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Proteínas de Transporte/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Ligação Proteica , Células Matadoras Naturais/metabolismo , Ligantes
3.
Eur Spine J ; 31(12): 3536-3543, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36173555

RESUMO

PURPOSE: The short rod technique (SRT) is a novel method for lumbar pedicle screw placement to reduce surgical trauma and avoid damage to the facet joint and articular surface. The core concept is to change the entry point and angle of the screw on the vertebrae at both ends in the sagittal plane to shorten the length of the longitudinal rods. The purpose of this study is to determine the sagittal screw angle (SSA) and its safe Maximum (MAX) value on each lumbar vertebra for the SRT and to observe the shortening effect on the longitudinal rods. METHODS: A total of 152 healthy adults were investigated by measuring the lumbar spine lateral view images. The SSA and MAX-SSA were measured with SRT as reference to the conventional placement technique method. The distance between the entry points of the proximal and distal vertebrae was measured to compare the changes in the length of the longitudinal rods using the two screw placement techniques. RESULTS: + SSA increased from L1 to L4, and -SSA increased from L2 to L5, in which the -SSA of L2, L3, and L4 were significantly greater than those of + SSA (P < 0.05). + MAX-SSA at L1-L4 was 23.26 ± 3.54°, 23.68 ± 3.37°, 24.12 ± 3.29°, and 24.26 ± 3.42°, respectively. -MAX-SSA at L2-L5 was 36.25 ± 3.26°, 38.26 ± 3.73°, 38.62 ± 3.63° and 37.33 ± 3.31°, respectively. Theoretical reductions by calculation for the 2-segment lumbar pedicles were: L1-2: 9 mm, L2-3: 9.29 mm, L3-4: 6.23 mm, and L4-5: 7.08 mm; And the 3-segment lumbar pedicles were: L1-3: 16.97 mm, L2-4: 16.73 mm, L3-5, and 18.24 mm, respectively. CONCLUSIONS: The application of the SRT to lumbar pedicles is a safe screw placement method that can significantly shorten the length of the used longitudinal rods.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Adulto , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Região Lombossacral , Tomografia Computadorizada por Raios X
4.
Bioconjug Chem ; 32(4): 667-671, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33689295

RESUMO

We report two cholesterol-modified oligonucleotides for use as internal controls for on-DNA reactions during the pooled stages of a DNA-encoded chemical library (DECL) synthesis. As these cholesterol-tagged oligonucleotides are chromatographically separable from normal DECL intermediates, they can be directly monitored by mass spectrometry to track reaction progression within a complex pool of DNA. We observed similar product conversions for reactions on substrates linked to a standard DECL DNA headpiece, to the cholesterol-modified oligonucleotides, and to the cholesterol-modified oligonucleotides while in the presence of pooled DECL synthetic intermediates-validating their use as a representative control. We also highlight an example from a DECL production in which the use of the cholesterol-modified oligonucleotides provided quality control information that guided synthetic decisions. We conclude that the use of cholesterol-modified oligonucleotides as a regular control will significantly improve the quality of DECL productions.


Assuntos
Colesterol/química , Oligonucleotídeos/química , Cromatografia Líquida/métodos , Técnicas de Química Combinatória , Espectrometria de Massas/métodos
5.
Cell Biol Int ; 45(2): 447-455, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33200464

RESUMO

Increasing evidence suggests that postmenopausal osteoporosis (PMO), a severe disturbance, imposes heavy physical, psychosocial, and financial burdens and dramatically influences the quality of life of postmenopausal women. Circular RNAs (circRNAs) and microRNAs (miRs) play important roles in the occurrence and development of PMO. However, the roles of circRNAs and miRs in osteoporosis regulation still need to be further investigated. circRNAs with different expression levels in patients with PMO were screened via RNA-seq and bioinformatics analysis. We found that circ_0007059 was upregulated in patients with PMO and during osteoclastogenesis of human bone marrow stromal cells (hBMSCs). Next, we investigated the effect of circ_0007059 overexpression during osteoclastogenesis of hBMSCs. circ_0007059 overexpression attenuated hBMSC differentiation into osteoclasts in vitro. This was demonstrated by downregulated bone morphogenetic protein 2 (BMP-2) expression, upregulated osteoclast-specific gene expression, and TRAP staining. circ_0007059 was demonstrated to directly target miR-378, which in turn targeted BMP-2 via bioinformatics analysis and the dual-luciferase reporter assay. Transfection of the miR-378 mimic reversed the effect of circ_0007059 on the osteoclastogenesis of hBMSCs. These results suggest that circ_0007059 plays an important role in osteoclastogenesis via the miR-378/BMP-2 signaling pathway. Targeting the circ_0007059/miR-378/BMP-2 axis is possibly a novel idea in osteoporosis treatment.


Assuntos
Osteogênese , Osteoporose Pós-Menopausa/metabolismo , RNA Circular/fisiologia , Idoso , Proteína Morfogenética Óssea 2/metabolismo , Linhagem Celular , Feminino , Humanos , Células-Tronco Mesenquimais , MicroRNAs/metabolismo , Pessoa de Meia-Idade
6.
Sensors (Basel) ; 21(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34283149

RESUMO

Implicit authentication mechanisms are expected to prevent security and privacy threats for mobile devices using behavior modeling. However, recently, researchers have demonstrated that the performance of behavioral biometrics is insufficiently accurate. Furthermore, the unique characteristics of mobile devices, such as limited storage and energy, make it subject to constrained capacity of data collection and processing. In this paper, we propose an implicit authentication architecture based on edge computing, coined Edge computing-based mobile Device Implicit Authentication (EDIA), which exploits edge-based gait biometric identification using a deep learning model to authenticate users. The gait data captured by a device's accelerometer and gyroscope sensors is utilized as the input of our optimized model, which consists of a CNN and a LSTM in tandem. Especially, we deal with extracting the features of gait signal in a two-dimensional domain through converting the original signal into an image, and then input it into our network. In addition, to reduce computation overhead of mobile devices, the model for implicit authentication is generated on the cloud server, and the user authentication process also takes place on the edge devices. We evaluate the performance of EDIA under different scenarios where the results show that i) we achieve a true positive rate of 97.77% and also a 2% false positive rate; and ii) EDIA still reaches high accuracy with limited dataset size.


Assuntos
Identificação Biométrica , Aprendizado Profundo , Computadores de Mão , Marcha , Privacidade
7.
Bioorg Med Chem Lett ; 30(7): 127004, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061500

RESUMO

In a lead optimization effort towards NS5B NNI inhibitors, two multi-step parallel libraries were designed and successfully synthesized. Through this effort we discovered compound 9B, which achieved rigorous and delicate balance of inhibition across the common genotypes and mutants with <10 nM potency. In addition, the bicyclic compounds 9B exhibited improved FASSIF solubility over the tetracyclic compound MK-8876. This strategic approach demonstrated that, even within limited reaction scope, multi-step parallel libraries could provide access to more complex chemical space. This expedient access facilitates diverse, purpose-driven optimization of SAR and physicochemical properties.


Assuntos
Antivirais/farmacologia , Benzofuranos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Benzofuranos/síntese química , Benzofuranos/farmacocinética , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacocinética , Hepacivirus/enzimologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ratos Wistar , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/farmacocinética , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
8.
Br J Neurosurg ; 34(3): 308-312, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32614272

RESUMO

Purpose: Tumor metastasis in the spine can cause pain and fractures, leading to deformities, and deficits in movement, sensation, and bowel/bladder function. Percutaneous vertebroplasty (PVP) and subtotal vertebral resection with reconstruction (SVR) are suitable treatments, but their relative clinical efficacy is uncertain. The purpose of this retrospective cohort study was to compare the management and clinical effect of SVR for lumbar metastatic tumor with PVP.Methods: Sixty-seven patients (mean age: 58.6 years) with metastases in the lumbar spine received SVR or PVP at our institution between 2010 and 2013. Thirty-three patients received SVR via a posterior approach, in which vertebrae were resected, with the anterior and lateral walls retained using polymethylmethacrylate (PMMA), followed by reconstruction and pedicle screw fixation. Thirty-four patients received PVP via the vertebral pedicle. Patients were followed for 3-26 months.Results: None of the patients experienced serious complications after surgery, and all patients experienced significant amelioration of pain. Twelve patients (8 in the PVP group and 4 in the SVR group) died during the follow-up, and the survival time was significantly longer in the SVR group. Two patients in the SVR group and 7 patients in the PVP groups experienced recurrence during follow-up, but the groups had no significant difference in local recurrence. Both treatments significantly reduced scores for pain on a visual analog scale (pain-VAS) and disability (Oswestry Disability Index [ODI]), and increased performance status (Karnofsky Performance Status [KPS]). Compared with the PVP group, the SVR group had better ODI score at 1 month and 3 months after surgery and a higher KPS score at 1 month after surgery. The two groups had no significant difference in pain-VAS scores during follow-up.Conclusions: SVR is a reliable treatment for lumbar metastatic tumor and provides good survival rate and satisfying follow-up results.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Vertebroplastia , Humanos , Vértebras Lombares/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento
9.
Bioorg Med Chem Lett ; 29(11): 1380-1385, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952592

RESUMO

The parallel medicinal chemistry (PMC) was effectively applied to accelerate the optimization of diacylglycerol O-acyltransferase I (DGAT-1) inhibitors. Through a highly collaborative and iterative library design, synthesis and testing, a benzimidazole lead was rapidly and systematically advanced to a highly potent, selective and bioavailable DGAT1 inhibitor with the potential for further development.


Assuntos
Benzimidazóis/farmacologia , Diacilglicerol O-Aciltransferase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/química , Química Farmacêutica , Diacilglicerol O-Aciltransferase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
10.
Am J Ther ; 26(1): e38-e44, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29087367

RESUMO

BACKGROUND: Percutaneous vertebroplasty (PVP) can not only alleviate pain but also restore mechanical stability with injection of bone cement, whereas it exhibits a poor effect on antitumor activity. But through combinations with other therapies, it may be possible to achieve the maximum effect in clinical treatment. Thus, this study is designed to assess the clinical efficacy of PVP separately combined with 4 ways for spinal metastasis (SM) treatment. STUDY QUESTION: Which combination treatment is better for spinal metastasis, percutaneous vertebroplasty with radiofrequency ablation, I seed, zoledronic acid or radiotherapy? STUDY DESIGN: A total of 169 patients with SM were retrospectively recruited and randomly assigned to 4 groups to receive 4 different ways separately: 49 patients (group A) received PVP plus I seed, 51 (group B) received PVP plus radiofrequency ablation (RFA), 38 (group C) underwent PVP plus zoledronic acid (ZA), and 31 (group D) underwent PVP plus radiotherapy (RT). MEASURES AND OUTCOMES: All of them underwent routine examinations before operation. Visual analog scale (VAS), World Health Organization (WHO) Pain Relief, and ODI were applied to evaluate pain relief and motor function. RESULTS: PVP plus RT achieved the best efficacy in relieving pains, with the highest WHO Pain Relief (P < 0.05). The PVP plus RFA exhibited lowest ODI, suggesting the best outcome after treatment (P < 0.05). The PVP plus I showed the lowest VAS score, but it was the worst to improve the routine exercise ability and relieve pains from patients. The PVP plus ZA presented higher VAS and ODI (P < 0.05). CONCLUSIONS: PVP combined with I seed exhibited the best clinical efficacy in terms of VAS, PVP combined with RT was the best choice in terms of WHO Pain Relief, and PVP combined with RFA showed the best effect in terms of ODI for the treatment of SM.


Assuntos
Dor do Câncer/terapia , Manejo da Dor/métodos , Neoplasias da Coluna Vertebral/terapia , Adulto , Idoso , Conservadores da Densidade Óssea/uso terapêutico , Braquiterapia/métodos , Dor do Câncer/diagnóstico , Dor do Câncer/etiologia , Terapia Combinada/métodos , Feminino , Seguimentos , Humanos , Radioisótopos do Iodo/administração & dosagem , Masculino , Pessoa de Meia-Idade , Medição da Dor , Ablação por Radiofrequência/métodos , Distribuição Aleatória , Estudos Retrospectivos , Neoplasias da Coluna Vertebral/complicações , Neoplasias da Coluna Vertebral/secundário , Resultado do Tratamento , Vertebroplastia/métodos , Ácido Zoledrônico/uso terapêutico
11.
J Am Chem Soc ; 140(22): 6797-6800, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29762027

RESUMO

Targeting tryptophan is a promising strategy to achieve high levels of selectivity for peptide or protein modification. A chemoselective peptide modification method via photocatalytic tryptophan ß-position conjugation has been discovered. This transformation has good substrate scope for both peptide and Michael acceptor, and has good chemoselectivity versus other amino acid residues. The endogenous peptides, glucagon and GLP-1 amide, were both successfully conjugated at the tryptophan ß-position. Insulin was studied as a nontryptophan control molecule, resulting in exclusive B-chain C-terminal-selective decarboxylative conjugation. This transformation provides a novel approach toward peptide modification to support the discovery of new therapeutic peptides, protein labeling and bioconjugation.


Assuntos
Peptídeos/química , Processos Fotoquímicos , Proteínas/química , Triptofano/química , Catálise/efeitos da radiação , Conformação Molecular
12.
Cell Physiol Biochem ; 42(2): 640-650, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28595186

RESUMO

BACKGROUND/AIMS: Insulin-like growth factor binding proteins (IGFBP) play important roles in bone metabolism. IGFBP4 is involved in senescent-associated phenomena in mesenchymal stem cells (MSCs). The goal of the present study was to determine whether age-related IGFBP4 overexpression is associated with the impaired osteogenic differentiation potential of aged bone marrow derived MSCs. METHODS: MSCs were isolated from Sprague-Dawley rats aged 3-26 months. The bone morphogenetic protein (BMP)-2-induced osteogenic differentiation of rat MSCs was assessed by analyzing the expression levels of osteoblast marker genes [runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), and osteocalcin (OC)], ALP activity and calcification. RESULTS: Our study showed that IGFBP4 mRNA and protein expression increased with age in parallel with impaired osteogenic differentiation of MSCs cultured in BMP2-containing osteogenic medium, as evidenced by the downregulation of osteoblast marker genes, and decreased ALP activity and calcium deposits. IGFBP4 overexpression impaired BMP2-induced osteogenic differentiation potential of young MSCs, whereas IGFBP4 knockdown restored the osteogenic potency of aged MSCs. Moreover, IGFBP4 knockdown stimulated the activation of Erk and Smad by increasing phosphorylation. CONCLUSION: Collectively, our results demonstrate that IGFBP4 overexpression plays a role in the impairment of MSC differentiation potential via the Erk and Smad pathways, suggesting potential targets to improve MSC function for cell therapy applications.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Diferenciação Celular/genética , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Células-Tronco Mesenquimais/metabolismo , Osteogênese/genética , Animais , Células da Medula Óssea/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica no Desenvolvimento , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Sistema de Sinalização das MAP Quinases/genética , Células-Tronco Mesenquimais/citologia , Osteoblastos/metabolismo , Fosforilação , RNA Mensageiro/biossíntese , Ratos , Proteínas Smad/genética
13.
Bioorg Med Chem Lett ; 27(11): 2559-2566, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28431879

RESUMO

SAR in the previously described spirocyclic ROMK inhibitor series was further evolved from lead 4 by modification of the spirocyclic core and identification of novel right-side pharmacophores. In this process, it was discovered that the spiropyrrolidinone core with the carbonyl group α to the spirocenter was preferred for potent ROMK activity. Efforts aimed at decreasing hERG affinity within the series led to the discovery of multiple novel right-hand pharmacophores including 3-methoxythiadiazole, 2-methoxypyrimidine, and pyridazinone. The most promising candidate is pyridazinone analog 32 that showed an improved functional hERG/ROMK potency ratio and preclinical PK profile. In vivo evaluation of 32 demonstrated blood pressure lowering effects in the spontaneously hypertensive rat model.


Assuntos
Canal de Potássio ERG1/metabolismo , Bloqueadores dos Canais de Potássio/química , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Animais , Modelos Animais de Doenças , Cães , Canal de Potássio ERG1/antagonistas & inibidores , Meia-Vida , Hipertensão/tratamento farmacológico , Bloqueadores dos Canais de Potássio/farmacocinética , Bloqueadores dos Canais de Potássio/uso terapêutico , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Pirimidinas/química , Ratos , Ratos Endogâmicos SHR , Compostos de Espiro/química , Relação Estrutura-Atividade , Tiadiazóis/química
14.
J Pharmacol Sci ; 134(1): 22-28, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28522217

RESUMO

Chondrosarcomas (CS) is the second most frequent tumors of cartilage origin. A small compound extracted from Thunder God Vine (Tripterygium wilfordii Hook. F.) called celastrol can directly bound CIP2A protein and effectively inhibit cell proliferation and induce apoptosis in several cancer cells. However, little knowledge is concern about the important role of CIP2A in CS patients and the therapeutic value of celastrol on CS. Our results showed that CIP2A and c-MYC were verified to be oncoproteins by detecting their mRNA and protein expression in 10 human CS tissues by qRT-PCR and Western blots. After treatment of celastrol, the proliferation, migration and invasion were significantly inhibited; whereas the apoptosis was largely induced in human CS cell lines. In addition, celastrol inhibited the expression of CIP2A, c-MYC, and suppressed apoptotic proteins BAX and caspase-8 in human CS cells, on the other hand, it induced the expression of antiapoptotic protein Bcl-2. Finally, knockdown of CIP2A also inhibited the migration and invasion and induced apoptosis of human CS cells. To sum up, we found that celastrol had effects on inhibiting proliferation, migration, invasion and inducing apoptosis through suppression CIP2A/c-MYC signaling pathway in vitro, which may provide a new therapeutic regimen for CS.


Assuntos
Autoantígenos/metabolismo , Condrossarcoma/tratamento farmacológico , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Triterpenos/farmacologia , Apoptose , Autoantígenos/genética , Caspase 8/genética , Caspase 8/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Condrossarcoma/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Membrana/genética , Invasividade Neoplásica , Triterpenos Pentacíclicos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Triterpenos/antagonistas & inibidores , Triterpenos/química , Triterpenos/uso terapêutico , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
15.
Tumour Biol ; 36(11): 8579-84, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26036761

RESUMO

Osteosarcoma has become one of the most common primary malignant bone tumors in childhood and adult. Numerous studies have demonstrated that aberrant microRNA (miRNA) expression is involved in human disease including cancer. To date, the potential miRNAs regulating osteosarcoma growth and progression are not fully identified yet. Herein, we showed that miR-375 was frequently downregulated in osteosarcoma tissue and cell lines compared to normal human colon tissues. Overexpression of miR-375 resulted in decreased expression of PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha) at both mRNA and protein levels. We found that miR-375 overexpression markedly suppressed cell proliferation in vitro. And inhibition of miR-375 promotes osteosarcoma growth. Mechanistic studies showed that PIK3CA was a potential target of miR-375 and it mediated reduction of PIK3CA resulted in suppression of PI3K/Akt pathway. Taken together, our results demonstrate that miR-375 functions as a growth-suppressive miRNA and plays an important role in inhibiting the tumorigenesis through targeting PIK3CA in osteosarcoma.


Assuntos
Transformação Celular Neoplásica/genética , MicroRNAs/biossíntese , Osteossarcoma/genética , Fosfatidilinositol 3-Quinases/biossíntese , Linhagem Celular Tumoral , Proliferação de Células/genética , Classe I de Fosfatidilinositol 3-Quinases , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Humanos , MicroRNAs/genética , Osteossarcoma/patologia , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais
16.
J Spinal Disord Tech ; 28(4): E244-50, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25756408

RESUMO

STUDY DESIGN: A comprehensive bioinformatics analysis of genes which may have correlations with ankylosing spondylitis (AS). OBJECTIVE: To study the mechanisms of AS by analyzing microarray of GSE25101. SUMMARY OF BACKGROUND DATA: AS is an inflammatory arthritis that can lead to chronic pain and disability. MATERIALS AND METHODS: GSE25101 was downloaded from Gene Expression Omnibus including 16 AS patients and 16 normal controls. The differentially expressed genes (DEGs) were screened using limma package in Bioconductor and miRNAs targeted DEGs were predicted. Then, gene ontology and pathway enrichment analysis of DEGs was performed using Database for Annotation, Visualization, and Integrated Discovery. Besides, the interaction relationships of the proteins encoded by DEGs were searched by STRING, and the protein-protein interaction (PPI) network was visualized by Cytoscape. Moreover, modules analysis of PPI network was performed using Clique Percolation Method in CFinder. RESULTS: A total of 284 DEGs were screened and 1899 miRNA-mRNA regulatory pairs were obtained. Both myosin heavy chain 9 (MYH9) and B-cell chronic lymphocytic leukemia/lymphoma 11B (BCL11B) were targeted by has-miR-124 and has-miR-363. Function enrichment analyze indicated that these DEGs, especially, downregulated protein tyrosine phosphatase receptor-type C (PTPRC), cluster of differentiation 3γ (CD3G), cluster of differentiation 247 (CD247), cluster of differentiation 4 (CD4), interleukin 7 receptor (IL7R), MYH9, and BCL11B were associated with regulation of immune response. Meanwhile, CD4 (degree=25), perforin 1 (PRF1) (degree=15), PTPRC (degree=13), and CD247 (degree=9) had higher connectivity degrees in the PPI network for the DEGs. And they might be involved in AS by interacting with other genes in module B (eg, PTPRC-IL7R, CD3G-CD247, and PRF1-PTPRC). CONCLUSION: MYH9, BCL11B, PTPRC, CD3G, CD247, CD4, IL7R, and PRF1 might have a correlation with AS.

17.
J Spinal Disord Tech ; 28(8): E454-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24984136

RESUMO

OBJECTIVE: To compare the effect of thoracoscopic anterior release combined with posterior spinal fusion and posterior-only approach with an all-pedicle screw construct in the treatment of rigid thoracic adolescent idiopathic scoliosis. METHODS: From June 2001 to June 2010, 63 patients who were admitted to our hospital with thoracic Cobb angle ≥80 degrees and the flexibility ≤40% were enrolled in our study. They were treated with either a combined anterior/posterior spinal fusion with hooks and screws (group A, n=25) or a posterior spinal fusion alone with an all-pedicle screw construct (group B, n=38). The thoracic Cobb angle in the standing whole-spine anteroposterior x-ray, thoracic kyphosis (T5-T12) Cobb angle, imaging examination parameters, fixation segments, implant density, and complications between the 2 groups were compared. RESULTS: There were no significant differences in operation time, bleeding volume, length of hospital stay, preoperative coronal, sagittal Cobb, coronal curve flexibility, or postoperative coronal Cobb correction ratio between the 2 groups. Moreover, no significant difference in the Scoliosis Research Society-22 score at the last follow-up was present in the 2 groups, although it had been improved compared with that presented during the preoperative period. The implant density of group A (44±4%) was significantly lower than that of group B (55±5%) (P<0.001). In group A, the main complication was chylothorax (n=2) and hemopneumothorax (n=2). In group B, acute intestinal obstruction was observed in 2 patients and pleural effusion was observed in 1 patient. In addition, 12 screws were misplaced (12/403, 3.0%) in group B. CONCLUSIONS: In patients with rigid thoracic adolescent idiopathic scoliosis, posterior-only approach with an all-pedicle screw construct could achieve the same curve correction as a combined anterior/posterior spinal fusion by increasing the implant density. However, for scoliosis patients with a high risk of implant complications, anterior release combined with posterior spinal fusion is still recommended.


Assuntos
Parafusos Pediculares , Escoliose/cirurgia , Fusão Vertebral/métodos , Vértebras Torácicas/cirurgia , Toracoscopia/métodos , Adolescente , Feminino , Seguimentos , Humanos , Masculino , Cuidados Pré-Operatórios , Radiografia , Estudos Retrospectivos , Escoliose/diagnóstico por imagem , Inquéritos e Questionários , Vértebras Torácicas/diagnóstico por imagem , Resultado do Tratamento
18.
Eur Spine J ; 23(11): 2369-74, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25231905

RESUMO

PURPOSE: To assess and characterize the sacrum angular displacements in response to lumbar lordosis after lumbar/lumbosacral fusion. METHODS: A finite element model of the lower lumbar spine-pelvis was established and used to simulate the posterior fusion at L3-L5 and L4-S1. The lordosis angle in the fusion segments was set to five different conditions with respect to the intact model: 10° less than intact, 5° less than intact, same as intact, 5° more than intact, and 10° more than intact. Variations of the sacrum angular displacements with lordosis changes were analyzed under loading setting of axial compression, flexion, extension, lateral bending, and axial rotation. RESULTS: Compared with the intact lordosis, both increased and decreased lumbar lordosis angles caused the sacrum angular displacements to be increased. The lordosis angle increased by 10° induced the most substantial increase in sacrum angular displacements. In addition, the sacrum angular displacements of the L4-S1 fusion model at different lordosis angles were higher than those of the L3-L5 fusion model. CONCLUSION: The sacrum angular displacements occur as a result of the fusion surgery (L4-S1) and the changes in lumbar lordosis.


Assuntos
Lordose/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Sacro/diagnóstico por imagem , Sacro/cirurgia , Fusão Vertebral , Adulto , Análise de Elementos Finitos , Humanos , Processamento de Imagem Assistida por Computador , Lordose/cirurgia , Masculino , Movimento , Parafusos Pediculares , Radiografia , Rotação
19.
Org Lett ; 26(20): 4365-4370, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38743933

RESUMO

DNA-encoded libraries (DELs) are a key technology for identifying small-molecule hits in both the pharmaceutical industry and academia, but their chemical diversity is largely limited to water-compatible reactions to aid in the solubility and integrity of encoding DNA tags. To broaden the DEL chemical space, we present a workflow utilizing DNA-cationic surfactant complexation that enables dissolution and reactions on-DNA in anhydrous organic solvents. We demonstrate its utility by developing DEL-compatible photoredox decarboxylative C(sp2)-C(sp3) coupling under water-free conditions. The workflow is optimized for the 96-well format necessary for large-scale DEL productions, and it enables screening and optimization of DEL-compatible reactions in organic solvents.


Assuntos
DNA , Interações Hidrofóbicas e Hidrofílicas , Tensoativos , Tensoativos/química , DNA/química , Estrutura Molecular , Bibliotecas de Moléculas Pequenas/química , Solventes/química
20.
Br J Neurosurg ; 27(2): 160-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22984982

RESUMO

BACKGROUND: Patients with spinal deformities and nerve compression due to spinal tuberculosis often require surgical intervention. The objective of this study was to assess the long-term therapeutic effectiveness of one-stage anterior debridement, bone grafting, and internal fixation for lower cervical tuberculosis with kyphosis. METHODS: Twenty-one patients with lower cervical tuberculosis and cervical kyphosis received one-stage anterior debridement, autologous iliac bone grafting, and internal plate fixation. Patients were followed-up postoperatively for at least 5 years. Outcome measures included neck pain using Visual Analogue Scale (VAS) scores, Frankel classification of spinal cord injury, and Cobb angle of cervical kyphosis. RESULTS: Eighteen patients had lesions in 2 vertebrae and 3 had lesions in 3 vertebrae. Cervical tuberculosis was cured in all patients. The mean preoperative VAS score for neck pain was 8 (range: 6-10), whereas the mean best postoperative VAS score was 0.6 (range: 0-3). Mean final VAS score was significantly higher than the best VAS score (2.14 vs. 0.62). Of the 13 patients with symptoms of spinal cord compression, 9 improved by 1 grade and 4 improved by 2 grades according to Frankel classification at final follow-up. The mean preoperative Cobb angle of cervical kyphosis was 29° (range: 15°-50°), whereas the mean postoperative Cobb angle at final follow-up was -1.8° (range: 2-7°). CONCLUSIONS: One-stage anterior debridement, bone grafting, and internal fixation can effectively remove lesions, decompress the nerve, reduce pain, and correct kyphosis in patients with cervical tuberculosis and associated kyphosis. Long-term postoperative outcomes were satisfactory.


Assuntos
Placas Ósseas , Transplante Ósseo/métodos , Vértebras Cervicais , Desbridamento/métodos , Cifose/cirurgia , Tuberculose da Coluna Vertebral/cirurgia , Adulto , Feminino , Humanos , Ílio/transplante , Masculino , Pessoa de Meia-Idade , Cervicalgia/cirurgia , Síndromes de Compressão Nervosa/cirurgia , Medição da Dor , Cuidados Pós-Operatórios/métodos , Estudos Prospectivos , Fusão Vertebral/métodos , Resultado do Tratamento , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA