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1.
Int Orthop ; 48(5): 1313-1321, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38485784

RESUMO

PURPOSE: Refracture is one of the main complications of bone transport, which brings additional physical and mental burden to surgeries and patients. We aimed to raise a new classification system of refracture-related bone transport based on the Simpson classification and to present our experience on treatment. METHODS: This retrospective analysis included 19 patients with refracture-related bone transport (average age of 37.7 years; 18 men). We developed a modified Simpson classification system to assist decision-making (conservative versus surgical). The ASAMI criteria were used to assess the outcomes at last follow-up. RESULTS: The mean follow-up was 12.3 ± 3.2 months. Complete union was achieved in all patients, with no reinfection. Based on the modified Simpson classification, refracture was Ia type (within regeneration area) in three cases, Ib (collapsed fracture at the regeneration area) in one case, Ic (stress fracture) in three cases, II (at the junction between the regenerate and original bone) in one case, III (at the docking site) in nine cases, and V (at distant site) in two cases. Refracture was managed conservatively in six cases and surgically in 13 cases. Average time to bone union was 2.8 ± 1.2 months in the conservative group versus 4.4 ± 1.4 months in the surgery group. Assessment at the final follow-up using the ASAMI criteria revealed excellent bone result in all patients, excellent functional results in six patients (31.6%), and good functional results in 13 patients. CONCLUSIONS: The modified Simpson classification could include refracture at the docking site and stress fracture in the regeneration zone and provide some guidance in determining the appropriate treatment strategy.


Assuntos
Fraturas de Estresse , Fraturas da Tíbia , Masculino , Humanos , Adulto , Tíbia/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/cirurgia
2.
J Org Chem ; 87(15): 9593-9606, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35833878

RESUMO

Asymmetric α-regioselective annulation of MBH carbonates with 4-arylmethylisoxazol-5-ones has been developed to afford spirocyclic oxindole derivatives containing three contiguous stereogenic centers and vicinal all-carbon quaternary chiral centers. This reaction exhibits a broad substrate scope and excellent functional group tolerance. Excellent yields with high diastereo- and enantioselectivities were obtained in this efficient organocatalytic reaction.

3.
Ann Plast Surg ; 78(6): 680-683, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27759585

RESUMO

OBJECTIVE: This study aims to observe the efficacies of microsurgical technique combined with the Zhuang's skin soft tissue expander in treating Hunter type III congenital microtia. METHODS: Fifty-eight patients (61 ears) were enrolled from 2003 to 2012; the skin tissue expander was embedded subepidermally in the first stage via the intrahairline longitudinal incision in the postauricular mastoid area, the diseased-side rib cartilage was then taken for preparing the ear bracket in the second stage, and the tragus was surgically reconstructed in the third stage. RESULTS: The mean follow-up lasted 6 months to 10 years, the results were satisfactory for 54 ears and acceptable for 5 ears, and 2 ears (in two patients) appeared with complications, including 1 case of ear flap expansion rupture and 1 case of postoperative lateral helix flap necrosis. CONCLUSIONS: The combination of microsurgical technique, Zhuang's skin soft tissue expander, and autogenous rib cartilage graft could achieve satisfactory results in treating Hunter type III congenital microtia, and the complications were less, so it was worthy of clinical applications.


Assuntos
Microtia Congênita/cirurgia , Cartilagem Costal/transplante , Microcirurgia/métodos , Procedimentos de Cirurgia Plástica/métodos , Transplante de Pele/métodos , Retalhos Cirúrgicos , Dispositivos para Expansão de Tecidos , Expansão de Tecido/métodos , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Resultado do Tratamento
4.
J Virol ; 87(13): 7210-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23637401

RESUMO

Herpes simplex virus 1 (HSV-1) protein ICP27 enables viral mRNA export by accessing the cellular mRNA export receptor TAP/NXF, which guides mRNA through the nuclear pore complex. ICP27 binds viral mRNAs and interacts with TAP/NXF, providing a link to the cellular mRNA export pathway. ICP27 also interacts with the mRNA export adaptor protein Aly/REF, which binds cellular mRNAs and also interacts with TAP/NXF. Studies using small interfering RNA (siRNA) knockdown indicated that Aly/REF is not required for cellular mRNA export, and similar knockdown studies during HSV-1 infection led us to conclude that Aly/REF may be dispensable for viral RNA export. Recently, the structural basis of the interaction of ICP27 with Aly/REF was elucidated at atomic resolution, and it was shown that three ICP27 residues, W105, R107, and L108, interface with the RNA recognition motif (RRM) domain of Aly/REF. Here, to determine the role the interaction of ICP27 and Aly/REF plays during infection, these residues were mutated to alanine, and a recombinant virus, WRL-A, was constructed. Virus production was reduced about 10-fold during WRL-A infection, and export of ICP27 protein and most viral mRNAs was less efficient. We conclude that interaction of ICP27 with Aly/REF contributes to efficient viral mRNA export.


Assuntos
Transporte Ativo do Núcleo Celular/fisiologia , Herpesvirus Humano 1/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Proteínas Nucleares/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Animais , Western Blotting , Chlorocebus aethiops , Primers do DNA/genética , Imunofluorescência , Células HeLa , Humanos , Imunoprecipitação , Hibridização In Situ , Análise em Microsséries , Mutagênese , Células Vero
5.
Front Neurosci ; 18: 1427384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948926

RESUMO

The nucleus tractus solitarii (NTS) plays a critical role in the homeostatic regulation of respiration, blood pressure, sodium consumption and metabolic processes. Despite their significance, the circuitry mechanisms facilitating these diverse physiological functions remain incompletely understood. In this study, we present a whole-brain mapping of both the afferent and efferent connections of Phox2b-expressing and GABAergic neurons within the NTS. Our findings reveal that these neuronal populations not only receive monosynaptic inputs primarily from the medulla oblongata, pons, midbrain, supra-midbrain and cortical areas, but also mutually project their axons to these same locales. Moreover, intense monosynaptic inputs are received from the central amygdala, the paraventricular nucleus of the hypothalamus, the parasubthalamic nucleus and the intermediate reticular nucleus, along with brainstem nuclei explicitly engaged in respiratory regulation. In contrast, both neuronal groups extensively innervate brainstem nuclei associated with respiratory functions, although their projections to regions above the midbrain are comparatively limited. These anatomical findings provide a foundational platform for delineating an anatomical framework essential for dissecting the specific functional mechanisms of these circuits.

6.
J Knee Surg ; 36(6): 644-651, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34979582

RESUMO

INTRODUCTION: Tibial plateau fractures are often accompanied with ligamental and meniscal injuries. Among which, the combined existence of Schatzker type IV fracture with anterior cruciate ligament (ACL) avulsion has been reported rarely. The purpose of this study was to determine the injury mechanism of Schatzker type IV fracture with ACL avulsion based on Mimics software. METHODS: Ninety-nine Schatzker type IV tibial plateau fractures were retrospectively analyzed by quantitative three-dimensional measurements. ACL avulsions were diagnosed through the data of computed tomography and magnetic resonance imaging. We simulated the knee posture when an injury occurred and defined different injury patterns. The chi-square test was used for determining the main mechanism which causes Schatzker type IV fractures associated with ACL avulsions. RESULTS: There were more ACL avulsions and more displaced ACL avulsions associated with the knee in flexion in the setting of Schatzker type IV fracture (p < 0.05). More ACL avulsions were found in the injury pattern of flexion-valgus than the other injury patterns of the same level (p < 0.05). The rotation of the tibial showed no significant difference in producing ACL avulsion fractures. CONCLUSION: This study found that a flexed knee at the occurrence of a Schatzker type IV tibial plateau fracture is a high-risk factor for causing associated ACL avulsion and producing more displaced avulsions. Flexion-valgus pattern was the main cause of Schatzker type IV fractures associated with ACL avulsions. The findings will help orthopedists understand the injury mechanism and enhance their awareness of such injuries to avoid unfavorable prognosis.


Assuntos
Fraturas da Tíbia , Fraturas do Planalto Tibial , Humanos , Ligamento Cruzado Anterior/patologia , Estudos Retrospectivos , Incidência , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/epidemiologia , Fraturas da Tíbia/etiologia , Software
7.
Nanomaterials (Basel) ; 13(23)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38063750

RESUMO

Two-dimensional electron gas (2DEG) at the (100) KTaO3(KTO) surface and interfaces has attracted extensive interest because of its abundant physical properties. Here, light illumination-induced semiconductor-metal transition in the 2DEG at the KTO surface was investigated. 2DEG was formed at the surface of KTO by argon ion bombardment. The 2DEG prepared with a shorter bombardment time (300 s) exhibits semiconducting behavior in the range of 20~300 K in the dark. However, it shows a different resistance behavior, namely, a metallic state above ~55 K and a semiconducting state below ~55 K when exposed to visible light (405 nm) with a giant conductivity increase of about eight orders of magnitude at 20 K. The suppression of the semiconducting behavior is found to be more pronounced with increasing light power. After removing the illumination, the resistance cannot recover quickly, exhibiting persistent photoconductivity. More interestingly, the photoresponse of the 2DEG below 50 K was almost independent of the laser wavelength, although the photon energy is lower than the band gap of KTO. The present results provide experimental support for tuning oxide 2DEG by photoexcitation, suggesting promising applications of KTO-based 2DEG in future electronic and optoelectronic devices.

8.
J Clin Oncol ; 41(6): 1275-1284, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36269898

RESUMO

PURPOSE: CARTIFAN-1 aimed to evaluate the efficacy and safety of ciltacabtagene autoleucel (cilta-cel), a B-cell maturation antigen-targeting chimeric antigen receptor T-cell therapy, in Chinese patients with relapsed/refractory multiple myeloma (RRMM). METHODS: This pivotal phase II, open-label study (ClinicalTrials.gov identifier: NCT03758417), conducted across eight sites in China, enrolled adult patients with RRMM who had received ≥ 3 lines of prior therapy, including a proteasome inhibitor and immunomodulatory drug. Patients received a single infusion of cilta-cel (target dose 0.75 × 106 chimeric antigen receptor-positive viable T cells/kg). The primary end point was overall response rate. Secondary end points included progression-free survival (PFS), overall survival (OS), and incidence and severity of adverse events (AEs). RESULTS: As of the clinical cutoff of July 19, 2021, 48 patients received a cilta-cel infusion. At an 18-month median follow-up, the overall response rate was 89.6% (95% CI, 77.3 to 96.5), with a median time to first response of approximately 1 month; 77.1% of patients (95% CI, 62.7 to 88.0) achieved complete response or better. Medians for duration of response, PFS, and OS were not reached. The 18-month PFS and OS rates were 66.8% (95% CI, 49.4 to 79.4) and 78.7% (95% CI, 64.0 to 88.0), respectively. Hematologic AEs were common, including anemia (100%), neutropenia (97.9%), lymphopenia (95.8%), and thrombocytopenia (87.5%). Cytokine release syndrome occurred in 97.9% of patients (35.4% grade 3/4); the median time to onset was 7 days, and the median duration was 5 days. Infections occurred in 85.4% of patients (37.5% grade 3/4). Ten deaths occurred after cilta-cel infusion, eight of which were due to treatment-related AEs. CONCLUSION: These data demonstrate a favorable risk-benefit profile for a single infusion of cilta-cel, resulting in early, deep, and durable responses in heavily pretreated patients with RRMM in China.


Assuntos
Anemia , Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Adulto , Humanos , Anemia/etiologia , Antígeno de Maturação de Linfócitos B , Terapia Baseada em Transplante de Células e Tecidos , População do Leste Asiático , Imunoterapia Adotiva , Mieloma Múltiplo/tratamento farmacológico , Receptores de Antígenos Quiméricos/uso terapêutico
9.
Artigo em Inglês | MEDLINE | ID: mdl-35096111

RESUMO

BACKGROUND: Cardiac fibrosis (CF) is major myocardial change in diabetic cardiomyopathy (DCM). Yangxinshi as a Chinese medicine formula is used to treat cardiovascular diseases. However, the exact effective mechanism of Yangxinshi on CF is still uncertain. Hence, based on the pharmacological network, predicting the active components, potential targets and pathways of Yangxinshi on diabetic fibrosis require to be further studied. MATERIALS AND METHODS: By using Cytoscape 3.6.0 Bisogenet plug-in, the active components of Yangxinshi were obtained and screened through TCMSP, and the PPI network of DCM-CF was constructed and then screened by CytoNCA plug-in. GO analysis and KEGG pathway enrichment analysis were carried out by Cluego plug-in. Combined with the results of network pharmacological analysis, cells in vitro were performed to verify the CF stimulated with high glucose or intervence with Yangxinshi, and the expressions of Cbl-b, p-smad2, and α-SMA were detected. RESULTS: Yangxinshi might play a key role in reversing cardiac fibrosis in individuals with DCM by regulating the signal pathway of CBL and promoted the expression of Cbl-b and inhibited the expression of p-smad2 and α-SMA, verifying some predictive work via network pharmacology. CONCLUSION: Based on network pharmacology, this study demonstrates that the beneficial effect of Yangxinshi on CF is related to the Cbl-b/smad2 pathway, providing an idea for the therapeutic effect of Yangxinshi on cardiac fibrosis in DCM.

10.
Toxicol Sci ; 185(2): 143-157, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-34735003

RESUMO

The association between ambient airborne fine particulate matter (PM2.5) exposure and respiratory diseases has been investigated in epidemiological studies. To explore the potential mechanism of PM2.5-induced pulmonary fibrosis, 60 mice were divided into 3 groups to expose to different levels of PM2.5 for 8 and 16 weeks: filtered air, unfiltered air, and concentrated PM2.5 air, respectively. BEAS-2B cells were treated with 0, 25, 50, and 100 µg/ml PM2.5 for 24 h. The biomarkers of pulmonary fibrosis, epithelial-mesenchymal transition, N6-methyladenosine (m6A) modification, and metabolism of mRNAs were detected to characterize the effect of PM2.5 exposure. The results illustrated that PM2.5 exposure induced pathological alteration and pulmonary fibrosis in mice. The expression of E-cadherin was decreased whereas vimentin and N-cadherin expression were increased in a dose- and time-dependent manner after PM2.5 exposure. Mechanistically, PM2.5 exposure increased the levels of METTL3-mediated m6A modification of CDH1 mRNA. As a target gene of miR-494-3p, YTHDF2 was upregulated by miR-494-3p down-regulation and then recognized m6A-modified CDH1 mRNA to inhibit the E-cad expression, consequently induced the EMT progression after PM2.5 exposure. Our study indicated that PM2.5 exposure triggered EMT progression to promote the pulmonary fibrosis via miR-494-3p/YTHDF2 recognized and METTL3 mediated m6A modification.


Assuntos
Transição Epitelial-Mesenquimal , Fibrose Pulmonar , Adenosina/análogos & derivados , Animais , Caderinas/genética , Camundongos , Material Particulado/toxicidade , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
J Med Chem ; 65(21): 14553-14577, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36269639

RESUMO

Resistance to 5-FU reduces its clinical efficacy for the treatment of colorectal cancer. Sphingosine-1-phosphate receptor 2 (S1PR2) has emerged as a potential target to reverse 5-FU-resistance by inhibiting the expression of dihydropyrimidine dehydrogenase (DPD). In this study, 38 novel S1PR2 antagonists based on aryl urea structure were designed and synthesized, and the structure-activity relationship was investigated based on the S1PR2 binding assay. Representative compound 43 potently interacts with S1PR2 with a KD value of 0.73 nM. It displays potent 5-FU resensitizing activity in multiple 5-FU-resistant tumor cell lines, particularly in SW620/5-FU (EC50 = 1.99 ± 0.03 µM) but shows no cytotoxicity in the normal colon cell line NCM460 up to 1000 µM. Moreover, 43 significantly enhances the antitumor efficacy of 5-FU in the SW620/5-FU animal model. These data suggest that 43 could be a novel lead compound for developing a 5-FU resensitizing agent.


Assuntos
Neoplasias Colorretais , Fluoruracila , Animais , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Antimetabólitos Antineoplásicos/farmacologia , Receptores de Esfingosina-1-Fosfato , Di-Hidrouracila Desidrogenase (NADP) , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia
12.
J Virol ; 84(7): 3373-81, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20089655

RESUMO

Cyclophilin A (CypA), predominantly located intracellularly, is a multifunctional protein. We previously reported decreased CypA levels in hepatocytes of transgenic mice expressing hepatitis B virus (HBV) surface antigen (HBsAg). In this study, we found that expression of HBV small surface protein (SHBs) in human hepatoma cell lines specifically triggered CypA secretion, whereas SHBs added extracellularly to culture medium did not. Moreover, CypA secretion was not promoted by the expression of a secretion deficient SHBs mutant, suggesting a close association between secretion of CypA and SHBs. Interaction between CypA and SHBs was observed by using coimmunoprecipitation and glutathione S-transferase pull-down assays. Hydrodynamic injection of the SHBs expression construct into C57BL/6J mice resulted in increased serum CypA levels and ALT/AST levels, as well as the infiltration of inflammatory cells surrounding SHBs-positive hepatocytes. The inflammatory response and serum ALT/AST level were reduced when the chemotactic effect of CypA was inhibited by cyclosporine and anti-CD147 antibody. Furthermore, higher serum CypA levels were detected in chronic hepatitis B patients than in healthy individuals. In HBV patients who had received liver transplantation, serum CypA levels declined dramatically after the loss of HBsAg as a consequence of liver transplantation. Taken together, these results indicate that expression and secretion of SHBs can promote CypA secretion, which may contribute to the pathogenesis of HBV infection.


Assuntos
Ciclofilina A/metabolismo , Antígenos de Superfície da Hepatite B/fisiologia , Hepatite B Crônica/etiologia , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Células Cultivadas , Ciclosporina/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Replicação Viral
13.
Zhonghua Xin Xue Guan Bing Za Zhi ; 39(11): 1029-32, 2011 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-22336457

RESUMO

OBJECTIVE: The aim of this study was to investigate the efficiency and safety of ibutilide for cardioversion of persistent atrial fibrillation (AF) during radiofrequency ablation. METHODS: Eighteen patients (16 males) with persistent atrial fibrillation were enrolled in this study. All patients underwent circumferential pulmonary vein ablation guided by a Carto three-dimensional mapping system. In addition, linear ablation at the top of the left atrium and the isthmus of mitral valves and complex fractionated atrial electrogram (CAFE) ablation were performed. All patients were still in either atrial fibrillation or atrial flutter after ablation, the patients were treated with 1 mg intravenous ibutilide injection within 10 minutes after unsuccessful ablation. Intravenous injection was stopped in case of sinus rhythm (SR) restoration or occurrence of severe adverse reactions such as ventricular tachycardia. Cardioversion rate within 30 min and adverse reactions within 4 h were observed. Patients were divided into either conversion group or non-conversion group according to whether AF was converted to sinus rhythm within 30 minutes after injection. RESULTS: Eleven patients (61.11%) converted to SR after ibutilide injection. There were no significant differences in gender, age, body mass index, left atrium and left ventricular function between conversion group and non-conversion groups. The average conversion time was (13.80 ± 7.64) min, left atrium scar area ratio was significantly larger in non-conversion group (12.40 ± 11.03)% than in conversion group (5.12 ± 3.83)%, P < 0.05. Ibutilide significantly prolonged the average wavelength of the AF wave (171.8 ± 29.5) ms vs. (242.0 ± 40.0) ms at baseline, P < 0.01. The QT interval at 30 min after ibutilide injection (0.39 ± 0.21) s was significantly longer than before injection (0.51 ± 0.08) s, P < 0.05. There was no serious arrhythmias or other adverse reactions post ibutilide injection. CONCLUSIONS: Ibutilide is highly effective and safe agent for cardioversion in patients underwent unsuccessful ablation. Left atrium scar area ratio is an important determinant for the conversion rate in this cohort.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/cirurgia , Sulfonamidas/uso terapêutico , Adulto , Idoso , Ablação por Cateter/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Medicine (Baltimore) ; 100(51): e28337, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34941137

RESUMO

ABSTRACT: This study aims to introduce a morphological classification of hyperextension tibial plateau fractures based on CT scans and to reveal the correlation between the anterior compression and posterior tension fractures.From January 2015 to January 2019, 37 patients with hyperextension tibial plateau fractures were studied retrospectively. Based on this classification, the fractures were divided into 2 groups: group A had anterolateral or anteromedial compression fractures while group B had both. Three observers classified the fractures and recorded the morphology and incidences of posterior plateau fractures and proximal fibular fractures.All 37 fractures were allocated to group A (n = 15; 40%) and B (n = 22; 60%). Of the posterior tibial plateau fractures, 10 (27%) fractures were defined as partial and 27 (73%) as total. Of the 37 fractures, 18 (49%) proximal fibular avulsion fractures were observed. There was a significant difference between groups A and B regarding the incidence of total posterior tibial plateau fractures (P < .05). However, there was no significant difference between the incidence of proximal fibular avulsion fractures in the 2 groups or the combined and non-combined type fractures in group B (P > .05).Hyperextension tibial plateau fractures with a decreased posterior slope angle always involve both the anteromedial and anterolateral plateaus. This CT-based classification may improve the understanding of fracture features and is helpful for planning treatment.


Assuntos
Fratura Avulsão , Traumatismos do Joelho , Tíbia/diagnóstico por imagem , Fraturas da Tíbia/terapia , Idoso , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Traumatismos do Joelho/diagnóstico por imagem , Traumatismos do Joelho/terapia , Articulação do Joelho , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fraturas da Tíbia/diagnóstico por imagem , Fraturas da Tíbia/epidemiologia , Tomografia Computadorizada por Raios X/métodos
15.
Eur J Med Chem ; 225: 113775, 2021 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-34411894

RESUMO

5-Fluorouracil (5-FU) and its prodrugs are the essential clinical drugs for colorectal cancer (CRC) treatment. However, the drug resistance of 5-FU has caused high mortality of CRC patients. Thus, it is urgent to develop reversal agents of 5-FU resistance. Sphingosine-1-phosphate receptor 2 (S1PR2) was proved to be a potential target for reversing 5-FU resistance, but the activity of known S1PR2 antagonists JTE-013 were weak in 5-FU-resistant cell lines. To develop more potent S1PR2 antagonists to treat 5-FU-resistant cancer, a series of JTE-013 derivatives were designed and synthesized. The most promising compound 40 could markedly reverse the resistance in 5-FU-resistant HCT116 cells and 5-FU-resistant SW620 cells via inhibiting the expression of dihydropyrimidine dehydrogenase (DPD). The key was that compound 40 with improved pharmacokinetic properties significantly increased the inhibitory rate of 5-FU in the SW620/5-FU cells xenograft model with no observable toxicity by inhibiting the expression of DPD in tumor and liver tissues. Altogether, these results suggest that compound 40 may be a promising drug candidate to reverse 5-FU resistance in the treatment of CRC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Desenho de Fármacos , Fluoruracila/farmacologia , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/síntese química , Fluoruracila/química , Humanos , Estrutura Molecular , Receptores de Esfingosina-1-Fosfato/metabolismo , Relação Estrutura-Atividade
16.
J Med Virol ; 82(1): 14-22, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19950238

RESUMO

Accumulating evidence suggests a key role of hepatocyte apoptosis in the pathogenesis of viral hepatitis B. It was found in this study that stable expression of small hepatitis B surface antigen (SHBs) in HepG2 and Huh7 cells increased susceptibility to apoptosis. Proteomic analysis of SHBs expressing HepG2 cells revealed 43 down-regulated and 38 up-regulated proteins. Some have been implicated in apoptosis, including glucose-regulated protein 78 kDa (GRP78), heterogeneous nuclear ribonucleoprotein H3 (hnRNP H), Rho GDP dissociation inhibitor (GDI), cystatin B, far upstream element-binding protein (FUSEbp), and TNF receptor-associated protein 1 (TRAP1). Differential expression of GRP78 and several other proteins was confirmed by Western blot analysis. Replenishing GRP78 improved cellular resistance to apoptosis, whereas reduction of GRP78 by siRNA increased susceptibility even in the absence of SHBs. Taken together, these results suggest that HBsAg plays a pro-apoptotic role through down-regulation of GRP78.


Assuntos
Regulação para Baixo , Glucose/farmacologia , Proteínas de Choque Térmico/metabolismo , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/patogenicidade , Hepatócitos/metabolismo , Apoptose , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Chaperona BiP do Retículo Endoplasmático , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Proteínas de Choque Térmico/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Células Hep G2 , Antígenos de Superfície da Hepatite B/genética , Hepatócitos/virologia , Humanos , Proteínas/genética , Proteínas/metabolismo , Proteômica , RNA Interferente Pequeno
17.
J Med Virol ; 81(2): 230-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19107969

RESUMO

In hepatitis B virus (HBV) replication cycle, pregenomic RNA undergoes splicing and the reverse transcribed defective genomes can be packaged and released. Various types of spliced defective HBV genomes have been isolated from the sera and liver tissues of viral hepatitis B patients. To explore the functions of a 2.2 kb double spliced HBV variant, a 3.2 kb full-length HBV isolate (#97-34) and its 2.2 kb double-spliced HBV variant (#AP-12) from the tumor tissue of a patient with hepatocellular carcinoma (HCC) were amplified and cloned. Sequencing results showed that #AP12 had deletions in pre-S2, part of pre-S1, S genes, part of the spacer, and part of the reverse transcriptase gene, while the X gene was intact. When this defective double-spliced genome and its full-length counterpart genome were co-transfected into HepG2 cells, the former was shown to enhance the replication of the latter, both by real-time PCR and Southern blotting. When a replication incompetent clone 97-34G1881A was used to co-transfect with #AP12, #AP12 DNA was increased, indicating that replication of the wild-type virus was not the only factor involved in this observation. However, the replication enhancing competency of #AP12 was shown to require an intact HBV X expression cassette. The double-spliced defective variant might contribute to persistent HBV replication in a subpopulation of HCC patients.


Assuntos
Carcinoma Hepatocelular/virologia , Vírus Defeituosos/genética , Genoma Viral/genética , Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Splicing de RNA , Replicação Viral , Linhagem Celular , Meios de Cultura/química , DNA Viral/análise , DNA Viral/genética , Genótipo , Hepatite B/sangue , Hepatite B/genética , Hepatite B/virologia , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Vírus da Hepatite B/isolamento & purificação , Humanos , Masculino , Dados de Sequência Molecular , Replicação Viral/genética , Replicação Viral/imunologia
18.
Sci Rep ; 8(1): 15005, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30301920

RESUMO

The TREX complex mediates the passage of bulk cellular mRNA export to the nuclear export factor TAP/NXF1 via the export adaptors ALYREF or UIF, which appear to act in a redundant manner. TREX complex recruitment to nascent RNA is coupled with 5' capping, splicing and polyadenylation. Therefore to facilitate expression from their intronless genes, herpes viruses have evolved a mechanism to circumvent these cellular controls. Central to this process is a protein from the conserved ICP27 family, which binds viral transcripts and cellular TREX complex components including ALYREF. Here we have identified a novel interaction between HSV-1 ICP27 and an N-terminal domain of UIF in vivo, and used NMR spectroscopy to locate the UIF binding site within an intrinsically disordered region of ICP27. We also characterized the interaction sites of the ICP27 homolog ORF57 from KSHV with UIF and ALYREF using NMR, revealing previously unidentified binding motifs. In both ORF57 and ICP27 the interaction sites for ALYREF and UIF partially overlap, suggestive of mutually exclusive binding. The data provide a map of the binding sites responsible for promoting herpes virus mRNA export, enabling future studies to accurately probe these interactions and reveal the functional consequences for UIF and ALYREF redundancy.


Assuntos
Interações Hospedeiro-Patógeno/genética , Proteínas Imediatamente Precoces/genética , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/genética , Proteínas Virais Reguladoras e Acessórias/genética , Transporte Ativo do Núcleo Celular/genética , Sítios de Ligação/genética , Núcleo Celular/genética , Exodesoxirribonucleases/genética , Regulação Viral da Expressão Gênica/genética , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/patogenicidade , Herpesvirus Humano 8/genética , Herpesvirus Humano 8/patogenicidade , Humanos , Íntrons/genética , Ressonância Magnética Nuclear Biomolecular , Proteínas de Transporte Nucleocitoplasmático/genética , Fosfoproteínas/genética , Ligação Proteica/genética , Transporte de RNA/genética , RNA Mensageiro/genética
19.
Biomed Pharmacother ; 96: 1411-1417, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29169723

RESUMO

Allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester), with quite a good range of hepatoprotective and antineoplastic properties, is a functional substance from garlic (Allium sativum L.) The purpose of this study was to provide evidence that allicin could protect 1,3-DCP-induced lipid metabolism disorder in HepG2 cells. Allicin reduced the accumulation of triglycerides (TG) and total cholesterol (TC) in 1,3-DCP-induced HepG2 cells. Allicin significantly increased the phosphorylation of AMP-activated protein kinase (AMPK) and down-regulated the levels of sterol regulatory element binding protein-1 (SREBP-1) and sterol regulatory element binding protein-2 (SREBP-2) in 1,3-DCP-induced HepG2 cells. Additionally, allicin had obvious recovery influence on the phosphorylation level of PKA and CREB in 1,3-DCP-induced HepG2 cells. These observations indicated that allicin alleviated lipid metabolism disorder induced by 1,3-DCP in HepG2 cells by regulating AMPK-SREBPs and PKA-CREB signaling pathways.


Assuntos
Metabolismo dos Lipídeos/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ácidos Sulfínicos/farmacologia , Proteínas Quinases Ativadas por AMP/metabolismo , Linhagem Celular Tumoral , Colesterol/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dissulfetos , Regulação para Baixo/efeitos dos fármacos , Células Hep G2 , Humanos , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/metabolismo
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