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The metabotropic glutamate receptors (mGlus) are involved in the modulation of synaptic transmission and neuronal excitability in the central nervous system1. These receptors probably exist as both homo- and heterodimers that have unique pharmacological and functional properties2-4. Here we report four cryo-electron microscopy structures of the human mGlu subtypes mGlu2 and mGlu7, including inactive mGlu2 and mGlu7 homodimers; mGlu2 homodimer bound to an agonist and a positive allosteric modulator; and inactive mGlu2-mGlu7 heterodimer. We observed a subtype-dependent dimerization mode for these mGlus, as a unique dimer interface that is mediated by helix IV (and that is important for limiting receptor activity) exists only in the inactive mGlu2 structure. The structures provide molecular details of the inter- and intra-subunit conformational changes that are required for receptor activation, which distinguish class C G-protein-coupled receptors from those in classes A and B. Furthermore, our structure and functional studies of the mGlu2-mGlu7 heterodimer suggest that the mGlu7 subunit has a dominant role in controlling dimeric association and G-protein activation in the heterodimer. These insights into mGlu homo- and heterodimers highlight the complex landscape of mGlu dimerization and activation.
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Receptores de Glutamato Metabotrópico/química , Microscopia Crioeletrônica , Humanos , Multimerização Proteica , Estrutura Terciária de ProteínaRESUMO
OBJECTIVE: This study was designed to investigate the regulatory effects of kinesin family member (KIF) 23 on anaplastic thyroid cancer (ATC) cell viability and migration and the underlying mechanism. METHODS: Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to analyze the levels of KIF23 in ATC cells. Besides, the effects of KIF23 and sirtuin (SIRT) 7 on the viability and migration of ATC cells were detected using cell counting kit-8, transwell and wound healing assays. The interaction between SIRT7 and KIF23 was evaluated by co-immunoprecipitation (Co-IP) assay. The succinylation (succ) of KIF23 was analyzed by western blot. RESULTS: The KIF23 expression was upregulated in ATC cells. Silencing of KIF23 suppressed the viability and migration of 8505C and BCPAP cells. The KIF23-succ level was decreased in ATC cells. SIRT7 interacted with KIF23 to inhibit the succinylation of KIF23 at K537 site in human embryonic kidney (HEK)-293T cells. Overexpression of SIRT7 enhanced the protein stability of KIF23 in HEK-293T cells. Besides, overexpression of KIF23 promoted the viability and migration of 8505C and BCPAP cells, which was partly blocked by silenced SIRT7. CONCLUSIONS: SIRT7 promoted the proliferation and migration of ATC cells by regulating the desuccinylation of KIF23.
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Sirtuínas , Carcinoma Anaplásico da Tireoide , Neoplasias da Glândula Tireoide , Humanos , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/metabolismo , Linhagem Celular Tumoral , Apoptose , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proliferação de Células/genética , Proteínas Associadas aos Microtúbulos , Sirtuínas/genética , Sirtuínas/farmacologiaRESUMO
In this study, we investigated the impact of microRNA-34a (miR-34a) on lower limb arteriosclerosis obliterans in rats through the Sirtuin 1 (Sirt1) signaling pathway. Thirty-six Sprague-Dawley rats were divided into normal, model, and miR-34a mimics groups. Rats in the normal group were raised normally, while the model group underwent lower limb arteriosclerosis obliterans induction and received saline injections. The miR-34a mimics group also underwent arteriosclerosis obliterans modeling but received miR-34a mimics injections. Immunohistochemistry revealed significantly increased vascular endothelial growth factor (VEGF) expression in both model and miR-34a mimics groups compared to the normal group, with the miR-34a mimics group showing higher levels. Western blotting indicated elevated Sirt1 protein expression in both non-normal groups, with the miR-34a mimics group exhibiting significantly higher levels. Quantitative polymerase chain reaction (qPCR) demonstrated higher levels of miR-34a, VEGF mRNA, and Sirt1 mRNA in the model group compared to the normal group, but significantly lower levels than the miR-34a mimics group. Enzyme-linked immunosorbent assay (ELISA) showed increased VEGF content in the model group compared to the normal group but decreased compared to the miR-34a mimics group. Hemorrheological detection revealed a reduced PU index in both non-normal groups compared to the normal group, with a significant increase in the miR-34a mimics group compared to the model group. Overall, miR-34a upregulation enhanced VEGF expression in rat blood vessels, ameliorating arterial blood flow in lower limb arteriosclerosis obliterans through the Sirt1 signaling pathway.
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Arteriosclerose Obliterante , Extremidade Inferior , MicroRNAs , Ratos Sprague-Dawley , Transdução de Sinais , Sirtuína 1 , Fator A de Crescimento do Endotélio Vascular , Animais , Sirtuína 1/metabolismo , Sirtuína 1/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Arteriosclerose Obliterante/genética , Arteriosclerose Obliterante/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Masculino , Extremidade Inferior/irrigação sanguínea , Ratos , Modelos Animais de Doenças , Artérias/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
PTPN2 is one of the members of the protein Tyrosine Phosphatases (PTPs) family. To explore the promotive effect of upregulated PTPN2 induced by inflammatory response or oxidative stress on the progression of thyroid cancer. PTPN2 level in thyroid cancer tissues and cell lines was detected. Kaplan-Meier method was applied for evaluating the prognostic value of PTPN2 in thyroid cancer patients. After stimulation of inflammatory response (treatment of IFN-γ and TNF-α), or oxidative stress (treatment of H2O2), protein level of PTPN2 in K1 cells was measured by Western blot. Regulatory effects of PTPN2 on EdU-positive staining and Ki-67 positive cell ratio in K1 cells either with H2O2 stimulation or not were determined. PTPN2 was upregulated in thyroid cancer tissues and cell lines. Its level was higher in metastatic thyroid cancer patients than those of non-metastatic ones. High level of PTPN2 predicted worse prognosis of thyroid cancer. Treatment of either IFN-γ or TNF-α upregulated protein level of PTPN2 in K1 cells. Meanwhile, H2O2 stimulation upregulated PTPN2, which was reversed by NAC administration. With the stimulation of increased doses of H2O2, EdU-positive staining and Ki-67 positive cell ratio were dose-dependently elevated. Silence of PTPN2 attenuated proliferative ability and Ki-67 expression in K1 cells either with H2O2 stimulation or not. Inflammatory response or oxidative stress induces upregulation of PTPN2, thus promoting the progression of thyroid cancer.
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Regulação Neoplásica da Expressão Gênica , Inflamação/metabolismo , Estresse Oxidativo , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Inativação Gênica , Humanos , Peróxido de Hidrogênio/farmacologia , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Metástase Neoplásica , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Neoplasias da Glândula Tireoide/patologiaRESUMO
OBJECTIVE: Occupant impact safety is critical for train development. This paper proposes a systematic procedure for developing validated numerical occupant crash scenarios for high-speed trains by integrating experimental, computational, and inverse methods. METHODS: As the train interior is the most potentially injury-causing factor, the material properties were acquired by mechanical tests, and constitutive models were calibrated using inverse methods. The validity of the seat material constitutive model was further verified via drop tower tests. Finite element (FE) and multibody (MB) models of train occupant-seat interactions in frontal impact were established in LS-DYNA and MADYMO software, respectively, using the experimentally acquired materials/mechanical characteristics. Three dummy sled crash tests with different folding table and backrest configurations were conducted to validate the numerical occupant-seat models and to further assess occupant injury in train collisions. The occupant impact responses between dummy tests and simulations were quantitatively compared using a correlation and analysis (CORA) objective rating method. RESULTS: Results indicated that the experimentally calibrated numerical seat-occupant models could effectively reproduce the occupant responses in bullet train collisions (CORA scores >80%). Compared with the train seat-occupant MB model, the FE model could simulate the head acceleration with slightly more acceptable fidelity, however, the FE model CORA scores were slightly less than for the MB models. The maximum head acceleration was 30 g but the maximum HIC score was 17.4. When opening the folding table, the occupant's chest injury was not obvious, but the neck-table contact and "chokehold" may potentially be severe and require further assessment. CONCLUSIONS: This study demonstrates the value of experimental data for occupant-seat model interactions in train collisions and provides practical help for train interior safety design and formulation of standards for rolling stock interior passive safety.
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Acidentes de Trânsito , Traumatismos Torácicos , Humanos , Pescoço , Aceleração , Postura Sentada , Fenômenos BiomecânicosRESUMO
BACKGROUND: Patients with myasthenia gravis (MG) lose part of their working or living ability due to illness, and bring burden to caregivers. The purpose of this study was to explore the factors related to caregivers' disease family burden for MG patients in Northwest China. METHODS: The study utilized our Myasthenia Gravis database and distributed online questionnaires to both MG patients and their caregivers. The questionnaires included a general data collection form, the Patient Health Questionnaire-9 (PHQ-9) scale, and the Caregivers' Family Burden Scale of Disease (FBSD). Univariate analysis and multivariate linear regression analysis were run, with FBSD as the outcome variable for separate analyses. RESULTS: 178 MG patients were eligible for inclusion in the analysis, of whom 80 patients' caregivers had a positive family burden of MG. The daily activity burden of the family and the economic burden of the family were the heaviest among the six dimensions of the caregivers' family disease burdens. The factors independently associated with FBSD were depression symptom level, MG severity classification and family's monthly per capita income (p < 0.05). CONCLUSIONS: Depression symptom level, MG severity classification and family's monthly per capita income are independent factors related to the caregivers' disease family burden for MG patients.
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Miastenia Gravis , Qualidade de Vida , Humanos , Estudos Transversais , Cuidadores , Efeitos Psicossociais da Doença , China/epidemiologia , Miastenia Gravis/epidemiologia , Inquéritos e QuestionáriosRESUMO
MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) orchestrates diverse environmental signals to facilitate cell growth and is frequently activated in cancer. Translocation of MTORC1 from the cytosol to the lysosomal surface by the RRAG GTPases is the key step in MTORC1 activation. Here, we demonstrated that transcription factors MEF2A and MEF2D synergistically regulated MTORC1 activation via modulating its cyto-lysosome shutting. Mechanically, MEF2A and MEF2D controlled the transcription of FNIP1 and FNIP2, the components of the FLCN-FNIP1 or FNIP2 complex that acts as a RRAGC-RRAGD GTPase-activating element to promote the recruitment of MTORC1 to lysosome and its activation. Furthermore, we determined that the pro-oncogenic protein kinase SRC/c-Src directly phosphorylated MEF2D at three conserved tyrosine residues. The tyrosine phosphorylation enhanced MEF2D transcriptional activity and was indispensable for MTORC1 activation. Finally, both the protein and tyrosine phosphorylation levels of MEF2D are elevated in human pancreatic cancers, positively correlating with MTORC1 activity. Depletion of both MEF2A and MEF2D or expressing the unphosphorylatable MEF2D mutant suppressed tumor cell growth. Thus, our study revealed a transcriptional regulatory mechanism of MTORC1 that promoted cell anabolism and proliferation and uncovered its critical role in pancreatic cancer progression.Abbreviation: ACTB: actin beta; ChIP: chromatin immunoprecipitation; EGF: epidermal growth factor; EIF4EBP1: eukaryotic translation initiation factor 4E binding protein 1; FLCN: folliculin; FNIP1: folliculin interacting protein 1; FNIP2: folliculin interacting protein 2; GAP: GTPase activator protein; GEF: guanine nucleotide exchange factors; GTPase: guanosine triphosphatase; LAMP2: lysosomal associated membrane protein 2; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MEF2: myocyte enhancer factor 2; MEF2A: myocyte enhancer factor 2A; MEF2D: myocyte enhancer factor 2D; MEF2D-3YF: Y131F, Y333F, Y337F mutant; MTOR: mechanistic target of rapamycin kinase; MTORC1: MTOR complex 1; NR4A1: nuclear receptor subfamily 4 group A member 1; RPTOR: regulatory associated protein of MTOR complex 1; RHEB: Ras homolog, mTORC1 binding; RPS6KB1: ribosomal protein S6 kinase B1; RRAG: Ras related GTP binding; RT-qPCR: real time-quantitative PCR; SRC: SRC proto-oncogene, non-receptor tyrosine kinase; TMEM192: transmembrane protein 192; WT: wild-type.
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Autofagia , Neoplasias Pancreáticas , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fatores de Transcrição/metabolismo , Neoplasias Pancreáticas/genética , Tirosina , Sirolimo , Proteínas de Transporte/metabolismoRESUMO
OBJECTIVE: This study aimed to investigate the effect of exercise on depressive-like behavior induced by chronic unpredictable mild stress (CUMS) in rats and to explore the role of the SIRT3/ROS/NLRP3 signaling pathway in this process. METHODS: Twenty-nine male 8-week-old Sprague Dawley rats were divided into a control group (CON) (nine rats) and a model group (twenty rats). Thirteen chronic stress stimuli were randomly applied once or twice per day for 35 days to induce depression in the model group rats. After the model was established, the model group rats were randomly divided into the CUMS group (CUMS) and the aerobic exercise + CUMS group (EX + CUMS). The EX + CUMS group received 8 weeks of aerobic exercise intervention for 6 days per week. Behavioral assessments were performed using the sucrose preference test and forced swimming test. The expression of SIRT3, NLRP3, IL-1ß, and IL-18 in the hippocampus was detected using RT-PCR. The ROS level in the hippocampus was detected using immunofluorescence. The protein levels of SIRT3 and NLRP3 in the hippocampus were detected using western blotting. The protein levels of IL-1ß and IL-18 in the hippocampus were measured using ELISA. RESULTS: After 5 weeks of chronic stress stimuli, the hippocampal function of rats in the CUMS model group was impaired, and their sucrose preference was reduced, while their forced swimming time was prolonged. The expression of SIRT3 decreased, ROS increased, and the expression of NLRP3 and the levels of IL-1ß and IL-18 increased. Aerobic exercise increased the sucrose preference of rats, shortened their immobility time, increased the expression of SIRT3, and reduced the levels of ROS, NLRP3, IL-1ß, and IL-18. CONCLUSION: Exercise can improve the depressive behavior of CUMS model rats, and its mechanism may be related to the upregulation of SIRT3 in the hippocampus, which plays an anti-inflammatory role.
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Heterodimerization of the metabotropic glutamate receptors (mGlus) has shown importance in the functional modulation of the receptors and offers potential drug targets for treating central nervous system diseases. However, due to a lack of molecular details of the mGlu heterodimers, understanding of the mechanisms underlying mGlu heterodimerization and activation is limited. Here we report twelve cryo-electron microscopy (cryo-EM) structures of the mGlu2-mGlu3 and mGlu2-mGlu4 heterodimers in different conformational states, including inactive, intermediate inactive, intermediate active and fully active conformations. These structures provide a full picture of conformational rearrangement of mGlu2-mGlu3 upon activation. The Venus flytrap domains undergo a sequential conformational change, while the transmembrane domains exhibit a substantial rearrangement from an inactive, symmetric dimer with diverse dimerization patterns to an active, asymmetric dimer in a conserved dimerization mode. Combined with functional data, these structures reveal that stability of the inactive conformations of the subunits and the subunit-G protein interaction pattern are determinants of asymmetric signal transduction of the heterodimers. Furthermore, a novel binding site for two mGlu4 positive allosteric modulators was observed in the asymmetric dimer interfaces of the mGlu2-mGlu4 heterodimer and mGlu4 homodimer, and may serve as a drug recognition site. These findings greatly extend our knowledge about signal transduction of the mGlus.
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Dimerização , Microscopia CrioeletrônicaRESUMO
The contact between passenger and the vehicle interior especially sidewall in train overturn derailment accident cause extremely serious injuries to passenger. It is regrettable that there are few relevant studies that account for overturning accidents and passenger injuries. In this study, the impact responses subject to sidewall and passenger injuries during train-overturn derailments are investigated. First, a theoretical model and a practical accident are used to validate the overturning multi-body dynamic model of an 8-car Electric Multiple Unit (EMU) coupled with a passenger. And then, the passenger's kinematic responses of baseline models with tray tables put back and put down are studied. The results of simulation cases with different train speeds (V), friction coefficients, chair distances (D), and passenger positions (P) show that V and D have a positive impact on passenger injuries. While the friction coefficient has an overall negative influence on the passenger's injuries, there are some irregular fluctuations. Generally, the sitting position farther away from the sidewall tends to be more dangerous for passengers. And the tray table plays an important role in protecting passengers under the same conditions. This study provides referential value for the study of train overturning accidents and guidance for the protection of passengers.
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Acidentes de Trânsito , Ferimentos e Lesões , Humanos , Fenômenos Biomecânicos , Simulação por Computador , Ferimentos e Lesões/etiologiaRESUMO
Background: Exercise has been widely reported to promote bone health, but it is unknown whether is associated with a reduction in advanced glycosylation end products (AGEs). This study aimed to investigate the effects of 14 weeks of cheerleading exercise on areal bone mineral density (aBMD) and AGEs. Methods: In this study, 46 female teenagers (age, 19.52 ± 1.21 years; body mass index, 20.15 ± 2.47 kg/m2) were randomly divided into a cheerleading group (CHE, n = 21) and a control group (CON, n = 25). The CHE group was subjected to cheerleading practice twice a week for 14 weeks; the CON group maintained their daily routine. Dual-energy X-ray absorptiometry was used to measure aBMD, and autofluorescence (AF) values were used to reflect AGEs. Physical fitness testing all-in-one machines are used to test body composition, cardiorespiratory fitness, muscle fitness and flexibility. A mixed ANOVA model was used to examine the effect of the intervention on each outcome. A multiple mediation model with covariates for physical activity and eating behaviors was performed to explore the mediators between cheerleading exercise and aBMD. Results: After 14 weeks of cheerleading practice, 1) aBMD increased significantly in both groups with significantly higher increases in the CHE group (p < 0.05). 2) AGEs significantly decreased in the CHE group (-2.7%), but not in the CON group (p > 0.05). 3) Vertical jumps and sit-ups significantly increased in the CHE group (p < 0.05), but not in the CON group (p > 0.05). 4) ΔAF values was significantly negatively correlated with Δ aBMD (r = -0.302, p < 0.05). 5) ΔAF values mediated the effect of exercise on the aBMD (indirect effect: 0.0032, 95% CI 0.0002-0.0079). Conclusion: Cheerleading practice improved aBMD and physical fitness and reduced AGEs accumulation in female adolescents. The effect of exercise on aBMD was partially mediated by AGEs.
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A reliable critical-scenario-based safety assessment of autonomous vehicles in China requires a thorough understanding of complex crash scenarios in Chinese background traffic. Based on actual crashes between a vehicle and a powered two-wheeler (PTW) in China, this study generated the autonomous driving testing scenarios from functional, logical and concrete levels. First, 239 video-recorded crash cases were selected from the China In-depth mobility Safety Study - Traffic Accident (CIMSS-TA) database. Using the k-medoids clustering method, six functional scenarios were generalized according to seven crash characteristics (time of day, road type, road surface, obstruction, motion of vehicle, motion of PTW, relative moving direction and position of PTW with respect to vehicle), which contained two straight road scenarios, two T-junction scenarios and two intersection scenarios. Then, using a trajectory analysis program written by Python, the dangerous time instant of each crash was extracted based on the relative trajectory. According to five dynamic parameters of dangerous time instant, namely vehicle velocity (Vehicle_V), PTW X'-coordinate velocity (PTW_VX'), PTW Y'-coordinate velocity (PTW_VY'), PTW X'-coordinate relative position (PTW_LocX') and PTW Y'-coordinate relative position (PTW_LocY'), a crash trigger scheme was built to remain a case challenging when the involved vehicle is replaced by an autonomous vehicle with completely different maneuvers. Using the kernel density estimation (KDE), the logical scenarios were evolved by calculating the distribution of these dynamic parameters in each cluster. The results showed that there were differences in the distribution of dynamic parameters between six functional scenarios. For instance, the Vehicle_V in the scenario where a vehicle turning right impacts with a right/right rear PTW traveling straight ahead was higher than that in the scenario where a vehicle changing to the left lane impacts with a left/left rear PTW traveling straight ahead, with ranges of (10 km/h, 30 km/h) and (5 km/h, 15 km/h), respectively. Finally, considering the correlation of dynamic parameters, a virtual crash generation approach based on the independent component analysis (ICA) representing the original crashes with independent parameters was proposed to obtain sufficient concrete testing scenarios. The results showed that the statistical characteristics of virtual crashes were consistent with those of original crashes. Therefore, the virtual crash generation approach was effective. And a concrete crossing testing scenario with the crash trigger conditions of Vehicle_V = 26.272 km/h, PTW_VX' = 15.567 km/h, PTW_VY' = -1.670 km/h, PTW_LocX' = -27.265 m and PTW_LocY' = 52. 149 m was especially demonstrated. This study provides a theoretical basis for generating autonomous driving testing scenarios and data support for establishing relevant testing schemes tailored to the traffic environment in China.
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Acidentes de Trânsito , Condução de Veículo , Acidentes de Trânsito/prevenção & controle , Análise por Conglomerados , Bases de Dados Factuais , Humanos , Compostos OrganotiofosforadosRESUMO
Cell-derived microparticles, which are recognized as nanosized phospholipid bilayer membrane vesicles, have exhibited great potential to serve as drug delivery systems in cancer therapy. However, for the purpose of comprehensive therapy, microparticles decorated with multiple therapeutic components are needed, but effective engineering strategies are limited and still remain enormous challenges. Herein, Bi2Se3 nanodots and doxorubicin hydrochloride (DOX) co-embedded tumor cell-derived microparticles (Bi2Se3/DOX@MPs) are successfully constructed through ultraviolet light irradiation-induced budding of parent cells which are preloaded with Bi2Se3 nanodots and DOX via electroporation. The multifunctional microparticles are obtained with high controllability and drug-loading capacity without unfavorable membrane surface destruction, maintaining their excellent intrinsic biological behaviors. Through membrane fusion cellular internalization, Bi2Se3/DOX@MPs show enhanced cellular internalization and deepened tumor penetration, resulting in extreme cell damage in vitro without considering endosomal escape. Because of their distinguished photothermal performance and tumor homing target capability, Bi2Se3/DOX@MPs exhibit admirable dual-modal imaging capacity and outstanding tumor suppression effect. Under 808 nm laser irradiation, intravenous injection of Bi2Se3/DOX@MPs into H22 tumor-bearing mice results in remarkably synergistic antitumor efficacy by combining photothermal therapy with low-dose chemotherapy in vivo. Furthermore, the negligible hemolytic activity, considerable metabolizability, and low systemic toxicity of Bi2Se3/DOX@MPs imply their distinguished biocompatibility and great potential for tumor theranostics.
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OBJECTIVE: To judge the efficacies of neural stem cell (NSC) transplantation on functional recovery following contusion spinal cord injuries (SCIs). DATA SOURCES: Studies in which NSCs were transplanted into a clinically relevant, standardized rat model of contusion SCI were identified by searching the PubMed, Embase and Cochrane databases, and the extracted data were analyzed by Stata 14.0. DATA SELECTION: Inclusion criteria were that NSCs were used in in vivo animal studies to treat contusion SCIs and that behavioral assessment of locomotor functional recovery was performed using the Basso, Beattie, and Bresnahan lo-comotor rating scale. Exclusion criteria included a follow-up of less than 4 weeks and the lack of control groups. OUTCOME MEASURES: The restoration of motor function was assessed by the Basso, Beattie, and Bresnahan locomotor rating scale. RESULTS: We identified 1756 non-duplicated papers by searching the aforementioned electronic databases, and 30 full-text articles met the inclusion criteria. A total of 37 studies reported in the 30 articles were included in the meta-analysis. The meta-analysis results showed that transplanted NSCs could improve the motor function recovery of rats following contusion SCIs, to a moderate extent (pooled standardized mean difference (SMD) = 0.73; 95% confidence interval (CI): 0.47-1.00; P < 0.001). NSCs obtained from different donor species (rat: SMD = 0.74; 95% CI: 0.36-1.13; human: SMD = 0.78; 95% CI: 0.31-1.25), at different donor ages (fetal: SMD = 0.67; 95% CI: 0.43-0.92; adult: SMD = 0.86; 95% CI: 0.50-1.22) and from different origins (brain-derived: SMD = 0.59; 95% CI: 0.27-0.91; spinal cord-derived: SMD = 0.51; 95% CI: 0.22-0.79) had similar efficacies on improved functional recovery; however, adult induced pluripotent stem cell-derived NSCs showed no significant efficacies. Furthermore, the use of higher doses of transplanted NSCs or the administration of immunosuppressive agents did not promote better locomotor function recovery (SMD = 0.45; 95% CI: 0.21-0.70). However, shorter periods between the contusion induction and the NSC transplantation showed slightly higher efficacies (acute: SMD = 1.22; 95% CI: 0.81-1.63; subacute: SMD = 0.75; 95% CI: 0.42-1.09). For chronic injuries, NSC implantation did not significantly improve functional recovery (SMD = 0.25; 95% CI: -0.16 to 0.65). CONCLUSION: NSC transplantation alone appears to be a positive yet limited method for the treatment of contusion SCIs.
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INTRODUCTION: Arteriosclerosis obliterans (ASO) is a disease that affects the lower extremities. The mechanism of ASO is associated with the proliferation and migration of vascular smooth muscle cells (VSMCs). miR-21 plays a key role in various biological processes of the cardiovascular system, associated with the proliferation, migration and apoptosis of VSMCs. It is unclear, however, if miR-21 is involved in the regulation of ASO. MATERIAL AND METHODS: Human aortic smooth muscle cells (HASMCs) were transfected with miR-21 mimics and co-treated with protein kinase B (AKT) or a mitogen-activated protein kinase (ERK) inhibitor. Expression levels of p-AKT or p-ERK were measured by western blot. Cell apoptosis was assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and visualized under a fluorescence microscope. Cell proliferation was monitored by bromodeoxyuridine (BrdU) labeling; cell migration and invasion were determined by the Transwell assay. RESULTS: miR-21 was upregulated in arteries of ASO, the pathogenesis of which involved the activation of p-AKT and p-ERK1/2. Inhibition of the AKT or ERK activity was consistent with the attenuation of the miR-21-induced HASMC migration and proliferation. HASMCs co-treated with miR-21 mimics and AKT or ERK inhibitor showed attenuation of the miR-21-induced high elongation ratio. CONCLUSIONS: We demonstrated that the expression of miR-21 in HASMCs could find potential application in cardiac therapy. Inhibition of the activity of AKT or ERK could attenuate miR-21-induced cell proliferation and migration as well as altering morphology of HASMCs. The present study aimed to indicate the potential roles of miR-21 in ASO processes, and the results provided a novel therapeutic approach for treating ASO and new targets for preventing ASO in earlier stages.
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With the development of the subway and the pressing demand of environmentally friendly transportation, more and more people travel by subway. In recent decades, the issues about passenger passive safety on the train have received extensive attention. In this research, the head injury of a standing passenger in the subway is investigated. Three MADYMO models of the different standing passenger postures, defined as baseline scenarios, are numerically set up. HIC15 values of passengers with different postures are gained by systematic parametric studies. The injury numerical simulation results of various scenarios with different friction coefficients, collision acceleration, standing angle, horizontal handrail height, and ring handrail height are analyzed. Results show that the horizontal handrail provides better protection in the three different standing passenger postures. Different friction coefficients and the standing angle have great impact on the head injuries of passengers in three different scenarios. The handrail height also has some effects on head injury of passengers with different standing postures, so it is necessary to be considered when designing the interior layout of the subway. This study may provide guidance for the safety design of the subway and some advices for standing subway passengers.
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Glioma has been considered as one of the most aggressive and popular brain tumors of patients. It is essential to explore the mechanism of glioma. In this study, we established PSMB8 as a therapeutic target for glioma treatment. Expression of PSMB8 as well as Ki-67 was higher in glioma tissues demonstrated by western blot and immunohistochemistry. Then, the role of PSMB8 in migration and proliferation of glioma cells was investigated by conducting wound-healing, trans-well assay, cell counting kit (CCK)-8, flow cytometry assay and colony formation analysis. The data showed that interfering PSMB8 may inhibit the migration and proliferation of glioma cells by reducing expression of cyclin A, cyclin B1, cyclin D1, Vimentin, and N-cadherin, and by increasing expression of E-cadherin. Additionally, interfering PSMB8 may induce apoptosis of glioma cells by upregulating caspase-3 expression. Furthermore, these in vitro findings were validated in vivo and the ERK1/2 and PI3k/AKT signaling pathways were involved in PSMB8-triggered migration and proliferation of glioma cells. In an in vivo model, downregulation of PSMB8 suppressed tumor growth. In conclusion, PSMB8 is closely associated with migration, proliferation, and apoptosis of glioma cells, and might be considered as a novel prognostic indicator in patients with gliomas.
Assuntos
Apoptose , Neoplasias Encefálicas/metabolismo , Movimento Celular , Proliferação de Células , Glioma/metabolismo , Complexo de Endopeptidases do Proteassoma/fisiologia , Transdução de Sinais , Animais , Apoptose/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Glioma/patologia , Humanos , Sistema de Sinalização das MAP Quinases/genética , Masculino , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/genéticaRESUMO
OBJECTIVE: To observe the effects of lyceum barbarum polysaccharide (LBP) on insulin resistance of HepG2 cells and investigate its possible mechanism. METHODS: IR-HepG2 cell model was induced with high glucose and high insulin in combination for 24 hours,with 104/vaccination in the 96-well plates, hole density after adherent cells (30 µg/mlã100 µg/mlã300 µg/ml) LBP cultivate 48 h, 200 µl/hole, each all had four holes. The effects of LBP at different concentrations on HepG2 cell activity and insulin resistance were tested. Intracellular malondialdehyde (MDA) content and superoxide dismutase (SOD) activity were detected. The expressions of related proteins in insulin signal transduction pathways such as insulin receptor substrate-2(IRS-2), phosphatidylinositol-3-kinase(PI3-K), protein kinase B(Akt) and glucose transport-2(GLUT2) were determined. RESULTS: Compared with normal control group, the content of MDA was increased significantly and the activity of SOD and the expression levels of IRS-2,PI-3K,Akt and GLUT2 were decreased significantly in the IR model group. Compared with IR model group, medium and high concentrations of LBP decreased the content of MDA and increased the activity of SOD and the expression levels of IRS-2, PI-3K, Akt and GLUT2 in insulin-resistant HepG2 cells. MTT showed that at the same time, the OD value gradually decreased with the increase of LBP's concentration; under the same concentration of LBP, the OD value also gradually decreased with the extension of time, which indicated that LBP inhibited the proliferation of HepG2 cells with time and concentration-dependent manner. Glucose consumption experiment indicated that medium and high concentration of LBP could increase the glucose consumption of insulin-resistant HepG2 cells significantly, but low concentration of LBP had no significant impacted on glucose consumption of insulin-resistant HepG2 cells. CONCLUSIONS: Medium and high concentration of LBP can improve insulin resistance of HepG2 cell, its mechanisns may be associated with decreasing the level of oxidative stress and increasing the protein expressions of insulin signaling pathway.
Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Resistência à Insulina , Transdução de Sinais/efeitos dos fármacos , Glucose , Transportador de Glucose Tipo 2/metabolismo , Células Hep G2 , Humanos , Insulina , Proteínas Substratos do Receptor de Insulina/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Polissacarídeos , Proteínas Proto-Oncogênicas c-akt/metabolismoRESUMO
AIM: To perform a systematic review and meta-analysis of randomized controlled trials to determine the efficacy and toxicity of approved vascular epithelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs) in advanced breast cancer. METHODS: A comprehensive literature search for studies published up to August 2013 was performed. The endpoints were overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and grade 3 or 4 adverse event (AEs). The pooled hazard ratio (HR) or relative risk (RR), and 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials. RESULTS: Twelve randomized controlled trials involved 3256 patients were ultimately identified. The intention to treatment (ITT) analysis demonstrated that VEGFR-TKI therapy significantly improved ORR (RR 1.14, 95% CI: 1.03-1.28, p = 0.016), but it did not translate into benefits in PFS (HR 0.99, 95% CI: 0.81-1.22, p = 0.93) and OS (HR 1.11, 95% CI 0.99-1.24, p = 0.084) when compared to non-VEGFR-TKI therapy. Additionally, a higher incidence of grade 3 or 4 anemia, neutropenia, thrombocytopenia, diarrhea, hand-foot syndrome and fatigue was observed in VEGFR-TKI-based therapy. CONCLUSIONS: The VEGFR-TKI-based therapy offered a significant improvement in ORR in patients with advanced breast cancer but did not benefit PFS and OS. With present available data from randomized clinical trials, we were still unable to clearly set the role of VEGFR-TKIs in the treatment of metastatic breast cancer (MBC).