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Noble gases with inert chemical properties have rich bonding modes under high pressure. Interestingly, Xe and Xe form covalent bonds, originating from the theoretical simulation of the pressure-induced decomposition of XeF2, which has yet to be experimentally confirmed. Moreover, the structural phase transition and metallization of XeF2 under high pressure have always been controversial. Therefore, we conducted extensive experiments using a laser-heated diamond anvil cell technique to investigate the above issues of XeF2. We propose that XeF2 undergoes a structural phase transition and decomposition above 84.1 GPa after laser heating, and the decomposed product Xe2F contains Xe-Xe covalent bonds. Neither the pressure nor temperature alone could bring about these changes in XeF2. With our UV-vis absorption experiment, I4/mmm-XeF2 was metalized at 159 GPa. This work confirms the existence of Xe-Xe covalent bonds and provides insights into the controversy surrounding XeF2, enriching the research on noble gas chemistry under high pressure.
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Materials that once suffered under high-pressure and high-temperature conditions often display unusual phenomena that challenge traditional understanding. MnF3, an intermediate valence state Mn-F compound, exhibits a distorted octahedral crystal structure influenced by the Jahn-Teller effect. Here we report the structural phase transition and self-disproportionation of MnF3 under high pressure and high temperature. The initial octahedra phase I2/a-MnF3 transforms into the hendecahedra Pnma phase under high pressure. Subsequently, we found that molten Pnma-MnF3 self-disproportionate into MnF2 and MnF4 with the aid of laser heating at a pressure above 57.1 GPa. Raman spectra and UV-vis absorption experiments confirmed these changes that were ultimately confirmed by synchrotron radiation XRD. The equation of states for the volume with the pressure of these Mn-F compounds was also given. This work expands the study of Mn-F systems and provides guidance for the behavior of transition metal fluorides under high pressures and high temperatures.
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Photocatalytic technology has been recently conducted to remove microbial contamination due to its unique features of nontoxic by-products, low cost, negligible microbial resistance and broad-spectrum elimination capacity. Herein, a novel two dimensional (2D) g-C3N4/Bi(OH)3 (CNB) heterojunction was fabricated byincorporating Bi(OH)3 (BOH) nanoparticles with g-C3N4 (CN) nanosheets. This CNB heterojunction exhibited high photocatalytic antibacterial efficiency (99.3%) against Escherichia coli (E. coli) under visible light irradiation, which was 4.3 and 3.4 times that of BOH (23.0%) and CN (28.0%), respectively. The increase in specific surface area, ultra-thin layered structure, construction of a heterojunction and enhancement of visible light absorption were conducive to facilitating the separation and transfer of photoinduced charge carriers. Live/dead cell staining, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) assays and scanning electron microscopy (SEM) have been implemented to investigate the damage to the cell membrane and the leakage of the intracellular protein in the photocatalytic antibacterial process. The e-, h+ and O2â¢- were the active species involved in this process. This study proposed an appropriate photocatalyst for efficient treatment of bacterial contamination.
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Escherichia coli , Grafite , Escherichia coli/efeitos da radiação , Catálise , Grafite/química , Antibacterianos/farmacologia , Antibacterianos/química , LuzRESUMO
Cu2V2O7/Cu3V2O8/g-C3N4 heterojunctions (CVCs) were prepared successfully by the reheating synthesis method. The thermal etching process increased the specific surface area. The formation of heterojunctions enhanced the visible light absorption and improved the separation efficiency of photoinduced charge carriers. Therefore, CVCs exhibited superior adsorption capacity and photocatalytic performance in comparison with pristine g-C3N4 (CN). CVC-2 (containing 2 wt% of Cu2V2O7/Cu3V2O8) possessed the best synergistic removal efficiency for removal of dyes and antibiotics, in which 96.2% of methylene blue (MB), 97.3% of rhodamine B (RhB), 83.0% of ciprofloxacin (CIP), 86.0% of tetracycline (TC) and 80.5% of oxytetracycline (OTC) were eliminated by the adsorption and photocatalysis synergistic effect under visible light irradiation. The pseudo first order rate constants of MB and RhB photocatalytic degradation on CVC-2 were 3 times and 10 times that of pristine CN. For photocatalytic degradation of CIP, TC and OTC, it was 3.6, 1.8 and 6.1 times that of CN. DRS, XPS VB and ESR results suggested that CVCs had the characteristics of a Z-scheme photocatalytic system. This study provides a reliable reference for the treatment of real wastewater by the adsorption and photocatalysis synergistic process.
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Poluentes Ambientais , Oxitetraciclina , Adsorção , Tetraciclina , Ciprofloxacina , Antibacterianos , Azul de MetilenoRESUMO
In this study, we first manufactured ultrathin g-C3N4 (CN) nanosheets by thermal etching and ultrasonic techniques. Then, EuVO4 (EV) nanoparticles were loaded onto CN nanosheets to form EuVO4/g-C3N4 heterojunctions (EVCs). The ultrathin and porous structure of the EVCs increased the specific surface area and reaction active sites. The formation of the heterostructure extended visible light absorption and accelerated the separation of charge carriers. These two factors were advantageous to promote the synergistic effect of adsorption and photocatalysis, and ultimately enhanced the adsorption capability and photocatalytic removal efficiency of methylene blue (MB). EVC-2 (2 wt% of EV) exhibited the highest adsorption and photocatalytic performance. Almost 100% of MB was eliminated via the adsorption-photocatalysis synergistic process over EVC-2. The MB adsorption capability of EVC-2 was 6.2 times that of CN, and the zero-orderreaction rate constant was 5 times that of CN. The MB adsorption on EVC-2 followed the pseudo second-order kinetics model and the adsorption isotherm data complied with the Langmuir isotherm model. The photocatalytic degradation data of MB on EVC-2 obeyed the zero-order kinetics equation in 0-10 min and abided by the first-order kinetics equation for10-30 min. This study provided a promising EVC heterojunctions with superior synergetic effect of adsorption and photocatalysis for the potential application in wastewater treatment.
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Azul de Metileno , Purificação da Água , Adsorção , Catálise , Luz , Azul de Metileno/químicaRESUMO
Dysfunction of histone deacetylase 10 (HDAC10) has been suggested in the carcinogenesis of cervical cancer (CC). However, its association with microRNAs (miRNAs) in CC remains exclusive. Hence, this study aims to probe the role of HDAC10 in regulating CC cell proliferation, migration, and invasion and its correlation with the screened-out miRNA target. Microarray analysis and RT-qPCR revealed that HDAC10 expressed poorly in CC cells relative to human immortalized endocervical cells (End1/E6E7). Moreover, HDAC10 downregulation predicted poor survival for patients with CC. Overexpression of HDAC10 reduced CC cell biological activities in vitro and tumor growth and lung metastases in vivo. miR-223, upregulated in CC, was regulated by HDAC10 through histone acetylation, while miR-223 inhibited the effects of HDAC10 overexpression in CC. miR-223 targeted the 3'-UTR of thioredoxin interacting protein (TXNIP) and suppressed its expression, leading to increased CC development in vitro and in vivo. TXNIP overexpression impaired Wnt/ß-catenin pathway activity in CC cells.
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Proteínas de Transporte/metabolismo , Histona Desacetilases/metabolismo , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/patologia , beta Catenina/metabolismo , Acetilação , Adulto , Animais , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Histonas/genética , Histonas/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genéticaRESUMO
Dysfunction of histone deacetylase 10 (HDAC10) has been suggested in the carcinogenesis of cervical cancer (CC). However, its association with microRNAs (miRNAs) in CC remains exclusive. Hence, this study aims to probe the role of HDAC10 in regulating CC cell proliferation, migration, and invasion and its correlation with the screened-out miRNA target. Microarray analysis and RT-qPCR revealed that HDAC10 expressed poorly in CC cells relative to human immortalized endocervical cells (End1/E6E7). Moreover, HDAC10 downregulation predicted poor survival for patients with CC. Overexpression of HDAC10 reduced CC cell biological activities in vitro and tumor growth and lung metastases in vivo. miR-233, upregulated in CC, was regulated by HDAC10 through histone acetylation, while miR-233 inhibited the effects of HDAC10 overexpression in CC. miR-223 targeted the 3'-UTR of thioredoxin interacting protein (TXNIP) and suppressed its expression, leading to increased CC development in vitro and in vivo. TXNIP overexpression impaired Wnt/ß-catenin pathway activity in CC cells. This article is protected by copyright. All rights reserved.
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Divergent interpretations have appeared in the literature regarding the structural nature and evolutionary behavior for photoluminescent CdSe nanospecies with sharp doublets in optical absorption. We report a comprehensive description of the transformation pathway from one CdSe nanospecies displaying an absorption doublet at 373/393â nm to another species with a doublet at 433/460â nm. These two nanospecies are zero-dimensional (0D) magic-size clusters (MSCs) with 3D quantum confinement, and are labeled dMSC-393 and dMSC-460, respectively. Synchrotron-based small-angle X-ray scattering (SAXS) returns a radius of gyration of 0.92â nm for dMSC-393 and 1.14â nm for dMSC-460, and indicates that both types are disc shaped with the exponent of the SAXS form factor equal to 2.1. The MSCs develop from their unique counterpart precursor compounds (PCs), which are labeled PC-393 and PC-460, respectively. For the dMSC-393 to dMSC-460 transformation, the proposed PC-enabled pathway is comprised of three key steps, dMSC-393 to PC-393 (Stepâ 1), PC-393 to PC-460 (Stepâ 2 involving monomer addition), and PC-460 to dMSC-460 (Stepâ 3). The present study provides a framework for understanding the PC-based evolution of MSCs and how PCs enable transformations between MSCs.
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For the first time a competitive immunoassay was developed by employing T-2 antibody-functionalized magnetite nanoparticles and T-2 toxin-conjugated fluorescent quantum dots (QDs). Free T-2 and the T-2-modified QDs compete for binding to antibody-modified magnetic beads; the magnetic beads collected by magnetic separation were subjected to fluorescence intensity analysis (with excitation/emission wavelengths at 460/616 nm). This competitive immunoassay for T-2 toxin determination was applied both in a microcentrifuge tube and on a 96-well plate. The dynamic range of the immunoassay is 1-100 ng mL-1, the limit of detection (LOD) is 0.1 ng mL-1, and determination was completed in about 40 min and 30 min in the microcentrifuge tube and 96-well plate, respectively. Moreover, the biolayer interferometry (BLI) technique was employed for T-2 determination for the first time, in which the conjugate of T-2 toxin and bovine serum albumin (BSA) was immobilized on the sensors before detection. Its average recovery of T-2 toxin from barley sample ranged from 82.00 to 123.33%, and the relative standard deviation (RSD) was between 9.42 and 15.73%. The LOD of the BLI-based assay is 5 ng mL-1, and it only takes 10 min to finish the determination. Graphical abstract.
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Corantes Fluorescentes/química , Imunoensaio/métodos , Interferometria/métodos , Nanopartículas de Magnetita/química , Pontos Quânticos/química , Toxina T-2/análise , Animais , Anticorpos Imobilizados/imunologia , Bovinos , Contaminação de Alimentos/análise , Hordeum/química , Limite de Detecção , Poliestirenos/química , Soroalbumina Bovina/química , Toxina T-2/imunologiaRESUMO
BACKGROUND In this study, we aimed to investigate the expression of NOD-like receptor protein 3 (NLRP3) and caspase-1 in fetal membrane and placental tissues of patients with premature rupture of membrane (PROM), and to explore their role in PROM. MATERIAL AND METHODS Ninety women participated in this study: a control group of 30 healthy pregnant women, 30 with PPROM, and 30 with TPROM. Immunohistochemistry streptavidin-peroxidase (SP) assay was used to detect the protein expression of NLRP3 and caspase-1 in the fetal membrane and placental tissues. RT-PCR was used to detect the mRNA expression of NLRP3 and caspase-1 in fetal membrane and placental tissues. RESULTS The results of SP showed that NLRP3 and caspase-1 were mainly expressed in the cytoplasm of epithelial cells, mesenchymal cells, and trophoblast cells in fetal membranes, and the cytoplasm of placental syncytiotrophoblasts and vascular endothelial cells in placental tissues. The expression of NLRP3 and caspase-1 in the TPROM group was significantly higher than that in the PPROM group and control group (p<0.05), and there was a significant difference between the PPROM group and the control group. The results of RT-PCR showed that the mRNA expression level of NLRP3 and caspase-1 in the TPROM group was significantly higher than that in the PPROM group and control group (p<0.05), and the expression of NLRP3 mRNA and caspase-1 mRNA in the PPROM group was significantly different from that in the control group (p>0.05). CONCLUSIONS The increased expression of NLRP3 and caspase-1 in fetal membrane and placental tissues may be associated with the development of PROM.
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Caspase 1/metabolismo , Membranas Extraembrionárias/metabolismo , Ruptura Prematura de Membranas Fetais/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Placenta/metabolismo , Adulto , Caspase 1/genética , Membranas Extraembrionárias/patologia , Feminino , Ruptura Prematura de Membranas Fetais/genética , Ruptura Prematura de Membranas Fetais/patologia , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Placenta/patologia , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: The invasion of colon cancer is associated with the tumor angiogenesis. Endostatin is an important anti-angiogenic agent, and the additive effect of endostatin with a chemotherapeutic agent, cyclophosphamide, on micrangium has not been established. METHODS: Male BALB/c strain nude mice were injected with human colorectal carcinoma cells (HCT-116). The mice were divided into four groups (n=15, each group) and were treated with different concentrations of endostatin (15, 10, and 5 mg/kg/day), cyclophosphamide (20, 10, and 5 mg/kg/day), and combination of endostatin/cyclophosphamide (15+20, 15+10, and 15+5 mg/kg/day). The tumor inhibition rate was evaluated, followed by the quantification of messenger ribonucleic acid (mRNA) and protein expression of notch signaling components NOTCH-1, NOTCH-3, NOTCH-4, JAG-1, DLL-4, Hes-1, and Hey-1 using quantitative polymerase chain reaction (qPCR). The protein expression of NOTCH-3, JAG-1, and DLL-4 was confirmed using western blotting. Microvessel density (MVD) was evaluated to detect micrangium following the treatment. RESULTS: The endostatin/cyclophosphamide-treated samples exhibited an additive effect on the tumor inhibition rate and the microvessel count. NOTCH-1, NOTCH-3, NOTCH-4, JAG-1, Hes-1, and Hey-1 expression levels were highly correlated and downregulated in the treated samples, whereas DLL-4 expression was upregulated that accounted for its anti-angiogenic property. CONCLUSIONS: The combination treatment of colon cancer with endostatin and a chemotherapeutic agent, cyclophosphamide proves to be an efficient therapeutic strategy to inhibit the rapid vasculature formation confirmed by the differential expression of notch signaling components.
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Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias do Colo/tratamento farmacológico , Ciclofosfamida/farmacologia , Endostatinas/farmacologia , Microvasos/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/metabolismo , Western Blotting , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Ciclofosfamida/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Endostatinas/uso terapêutico , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase , Distribuição Aleatória , Receptores Notch/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: To explore the thrombomodulin (TM) expression levels changes in plasma and placenta in patients with early onset severe preeclampsia. METHODS: Sixty cases of severe preeclampsia women who delivered in the affiliated Xuzhou Maternity and Child Health Care Hospital of Xuzhou Medical College were enrolled in the study from June 2012 to February 2014, including 30 patients with early onset severe preeclampsia (early onset group), and 30 patients with late onset severe preeclampsia (late onset group). Healthy pregnant women were divided into two control groups according to gestational weeks at delivery: early control group (n = 23, at 28-33âº6 weeks), and late control group (n = 30, delivered after 34 weeks). ELISA was used to detect the levels of TM in plasma. Immunohistochemistry SP was applied to detect the TM protein expression on placenta. TM mRNA was determined by reverse transcription polymerase chain reaction (RT)-PCR technique. RESULTS: (1) TM level in plasma in early onset group and late onset group were (90.8 ± 6.9) and (87.5 ± 7.0) µg/L, and TM level in plasma in early control group and late control group were (37.7 ± 2.3) and (37.7 ± 2.5) µg/L. Plasma TM level in early onset group was higher than that in late onset group, early control group and late control group. The TM level had no statistically significant compare of early-onset group to late onset group. (P > 0.05). The plasma TM level in early onset group was significantly higher than that in early control group (P < 0.05), and the plasma TM level in late onset group was significantly higher than that in late control group (P < 0.05). (2) TM expressed mainly in the membrane and cytoplasm of placental syncytiotrophoblasts and endothelial cells. The expression of TM protein in early onset group was 47% (14/30), significantly lower than that in late onset group, early control group and late control group (P < 0.05), in which the positive rate were 90% (27/30), 91% (21/23) and 93% (28/30) respectively (P < 0.05). There was no difference between late onset group and late control group (P > 0.05). There was no difference between early control group and late control group (P > 0.05). (3) TM mRNA expression in early onset group, late onset group, early control group and late control group were 0.14 ± 0.06, 0.89 ± 0.23, 0.88 ± 0.22 and 0.93 ± 0.19, respectively. The expression of TM mRNA in early onset group was significantly lower than that in late onset group, early control group and late control group (P < 0.05), and the difference between early control group and late control group was not statistically significant (P > 0.05). There was no difference between late onset group and late control group (P > 0.05). There was no difference between early control group and late control group (P > 0.05). CONCLUSIONS: Decreased expression of TM in placenta may be associated with the pathogenesis of early onset severe preeclampsia, there may be different pathogenesis in early onset and late onset severe preeclampsia.
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Sangue Fetal/metabolismo , Placenta/metabolismo , Pré-Eclâmpsia/sangue , Trombomodulina/metabolismo , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Placenta/irrigação sanguínea , Gravidez , RNA Mensageiro , Trombomodulina/sangue , TrofoblastosRESUMO
OBJECTIVE: To investigate the expression of heat shock protein 70 (HSP70) in maternal serum, umbilical cord blood and placenta of patients with hypertensive disorders complicating pregnancy (HDCP) and to discuss its role in the pathogenesis of HDCP. METHODS: Totally 90 patients with HDCP were recruited as HDCP group, and were devided into three subgroups, including gestational hypertension group (30 cases), mild preeclampsia group (30 cases) and severe preeclampsia group (30 cases). A totally of 30 cases of healthy pregnant women were defined as the control group. All of them were admitted to Xuzhou Maternity and Child Health Care Hospital from August 2011 to December 2012. ELISA was used to detect the expression of HSP70 in maternal serum and umbilical cord blood. Immunohistochemistry streptavidin peroxidase (SP) was used to detect the protein in placenta, and semi-quantitative reverse transcription (RT)- PCR was used to detect the expression of HSP70 mRNA. RESULTS: (1) The levels of HSP70 in maternal serum and cord blood of mild preeclampsia group were (2.61 ± 0.98) and (0.78 ± 0.27) µg/L, respectively; and were (3.10 ± 1.18) and (0.96 ± 0.28) µg/L in severe preeclampsia group. The levels of HSP70 in mild and severe preeclampsia groups were significantly higher than those in the control group [(1.88 ± 0.79) and (0.61 ± 0.15) µg/L, respectively] and gestational hypertension group [(2.13 ± 0.71) and (0.64 ± 0.18) µg/L, respectively; P < 0.05]. The level of HSP70 in severe preeclampsia group was significantly higher than that in mild preeclampsia group (P < 0.05). And the level of HSP70 in gestational hypertension group was higher than that in the control group, but there was no statistical difference (P > 0.05). (2) The positive rate of placental HSP70 in gestational hypertension group, mild and severe preeclampsia group [83% (25/30), 90% (27/30) and 100% (30/30)], respectively were significantly higher than those in the control group (43%, 13/30; P < 0.05). The positive rate of placental HSP70 in severe preeclampsia group was significantly higher than that in gestational hypertension group and mild preeclampsia group (P < 0.05). (3) The expression of placental HSP70 mRNA in gestational hypertension group, mild and severe preeclampsia group (0.82 ± 0.27, 0.92 ± 0.26 and 1.36 ± 0.29, respectively) were significantly higher than that in the control group (0.45 ± 0.18), with statistically significant differences (P < 0.05). The expression of placental HSP70 mRNA in severe preeclampsia group was significantly higher than that in gestational hypertension group and mild preeclampsia group (P < 0.05). CONCLUSION: The expression of HSP70 increased significantly in maternal serum, umbilical cord blood and placenta of patients with HDCP, and it had positive correlation with the severity of the disease, indicating that HSP70 may play a role in the pathogenesis of HDCP.
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Sangue Fetal/metabolismo , Proteínas de Choque Térmico HSP70/sangue , Hipertensão Induzida pela Gravidez/metabolismo , Placenta/metabolismo , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Hipertensão Induzida pela Gravidez/sangue , Imuno-Histoquímica , Placenta/irrigação sanguínea , Pré-Eclâmpsia/sangue , Gravidez , RNA Mensageiro , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de DoençaRESUMO
Although evidence indicates that the abnormal accumulation of α-synuclein (α-syn) in dopamine neurons of the substantia nigra is the main pathological feature of Parkinson's disease (PD), no compounds that have both α-syn antiaggregation and α-syn degradation functions have been successful in treating the disease in the clinic. Here, it is shown that black phosphorus nanosheets (BPNSs) interact directly with α-syn fibrils to trigger their disaggregation for PD treatment. Moreover, BPNSs have a specific affinity for α-syn through van der Waals forces. And BPNSs are found to activate autophagy to maintain α-syn homeostasis, improve mitochondrial dysfunction, reduce reactive oxygen species levels, and rescue neuronal death and synaptic loss in PC12 cells. It is also observed that BPNSs penetrate the blood-brain barrier and protect against dopamine neuron loss, alleviating behavioral disorders in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced mouse model and hA53T α-syn transgenic mice. Together, the study reveals that BPNSs have the potential as a novel integrated nanomedicine for clinical diagnosis and treatment of neurological diseases.
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Doença de Parkinson , Fósforo , Espécies Reativas de Oxigênio , alfa-Sinucleína , Animais , Fósforo/química , Camundongos , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , alfa-Sinucleína/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células PC12 , Ratos , Nanoestruturas/química , Autofagia/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Camundongos Transgênicos , Modelos Animais de Doenças , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Humanos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacosRESUMO
BACKGROUND: Ultrasound-guided axillary vein (AxV) cannulation has been described as an effective alternative to internal jugular vein cannulation in adult cardiac surgical patients. However, the learning curve for this technique has not yet been addressed. This study aimed to determine the number of cases required to achieve proficiency in performing AxV cannulation among novice anesthesiologists. METHODS: This prospective study included the first 60 patients who underwent ultrasound-guided AxV cannulation performed by a single third-year resident who was trained in adult cardiac anesthesia. This study investigated the number of cases required to gain technical proficiency by applying cumulative sum analysis on the learning curve (LC-CUSUM) of ultrasound-guided AxV cannulation. RESULTS: Based on the assessment of the CUSUM plots, a descending inflection point for decreasing the overall procedural time for AxV cannulation was observed after patient 29. Regarding the procedural outcomes, comparing the early-experience group with the late-experience group (29 vs 31 cases), the former group had longer operating time (1526 s vs 1120 s, p < 0.001) and identification time (110 s vs 92 s, p < 0.001) and lower first-attempt success rate (8, 27.6% vs 30, 96.8%, p < 0.001) than the latter group. CONCLUSIONS: CUSUM demonstrated that at least 29 successful cases are required to achieve an expertized manipulation in ultrasound-guided AxV cannulation for inexperienced novices. The learning curve for ultrasound-guided AxV cannulation was observed in 29 cases. After adequate training, the overall procedural time and the first-attempt success rate, and puncture-related complications for AxV cannulation improved with increased experience.
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Veia Axilar , Cateterismo Venoso Central , Adulto , Humanos , Veia Axilar/diagnóstico por imagem , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Estudos Prospectivos , Ultrassonografia de Intervenção/métodos , Ultrassonografia , Veias Jugulares/diagnóstico por imagemRESUMO
For those colloidal semiconductor CdSe nanospecies that exhibit sharp optical absorption doublets, different explanations have appeared in the literature regarding their morphological nature and formation, with no consensus reached. Here, we discuss the transformation pathway in two types of CdSe nanoplatelets (NPLs), from NPL-393 to NPL-460, exhibiting absorption doublets at 373/393 and 433/460 nm, respectively. Synchrotron-based small/wide-angle X-ray scattering (SAXS/WAXS) was performed to monitor the in situ transformation associated with the temperature. Combining the results of SAXS/WAXS, optical spectroscopy, and transmission electron microscopy, we propose that the transformation pathway experiences corresponding magic-sized clusters (MSCs), which display similar optical properties but with zero-dimensional structure. From stacked NPL-393 to stacked NPL-460, the transformation goes through sequentially individual NPL-393, MSC-393, MSC-460, and individual NPL-460 at their corresponding characteristic temperature. The present findings provide compelling evidence that both MSCs and their assembled NPLs exhibit similar optical absorption.
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High-quality P6322 Mn2N0.86 samples were synthesised using a high-pressure metathesis reaction, and the properties of the material were investigated. The measurements revealed that the Vickers hardness was 7.47 GPa, which is less than that predicted by commonly used theoretical models. At low air pressure, Mn2N0.86 and MnO coexist at 500 to 600 °C, and by excluding air, we succeeded in producing Mn4N by heating Mn2N0.86 in nitrogen atmosphere; we carefully studied this process with thermogravimetry and differential scanning calorimetry (TG-DSC). This gives a hint that to control temperature, air pressure and gas concentration might be an effective way to prepare fine Mn-N-O catalysis. Magnetic measurements indicated that ferromagnetism and antiferromagnetism coexist within Mn2N0.86 at room temperature and that these magnetic properties are induced by nitrogen vacancies. Ab intio simulation was used to probe the nature of the magnetism in greater detail. The research contributes to the available data and the understanding of Mn2N0.86 and suggests ways to control the formation of materials based on Mn2N0.86.
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BACKGROUND: Evidence has been shown that long noncoding RNAs (lncRNAs) play an important role in the development of cervical cancer. Recently, lncRNA DARS-AS1 was reported to be dysregulated in several cancer types; however, the role of DARS-AS1 in cervical cancer remains unclear. METHODS: Flow cytometry and transwell invasion assays were performed to determine the apoptosis and invasion in cervical cancer cells. In addition, RNA pull-down and fluorescence in situ hybridization (FISH) assays were conducted to assess the interaction between DARS-AS1 and IGF2BP3 in cervical cancer cells. RESULTS: Downregulation of DARS-AS1 significantly induced apoptosis and cell cycle arrest in cervical cancer cells. Meanwhile, the invasion ability of cervical cancer cells was inhibited by DARS-AS1 knockdown as well. RNA pull-down and FISH results showed that DARS-AS1 interacted with IGF2BP3. Mechanistically, DARS-AS1 positively regulated IGF2BP3 expression via stabilization of IGF2BP3 mRNA. Rescue assays confirmed that DARS-AS1 regulated the progression of cervical cancer through interacting with IGF2BP3 in vitro. In addition, in vivo experiments revealed that downregulation of DARS-AS1 inhibited tumor growth in SiHa xenograft model. CONCLUSION: In this study, we found that downregulation of DARS-AS1 could inhibit the growth of cervical cancer cells via inhibition of IGF2BP3, suggesting DARS-AS1 might serve as a potential target for the treatment of cervical cancer.
RESUMO
Nanopeptide assembled from peptide-anchored nanoparticles possess an enormous research potential in the field of cellular medicine and disease treatment. The aim of this study was to explore the neuroprotective effects of maize tetrapeptide anchored gold nanoparticles against l-glutamic acid-induced PC12 cell apoptosis and a murine Alzheimer's disease model induced by aluminum chloride and d-galactose. The results revealed that the nanopeptide antioxidant inhibited intracellular ROS accumulation and promoted cell differentiation than that of maize bioactive tetrapeptide. Compared with untreated Alzheimer's disease model mice, nanopeptide administration shortened the escape latency time in a water maze test and improved the movements in the autonomic activity test. After 16 days of nanopeptide administration, the central cholinergic system function of acetylcholine and cholineacetyltransferase were enhanced, and the level of acetylcholinesterase was reduced. It also increased superoxide dismutase and glutathione peroxidase activity in sera and hypothalami. Moreover, nanopeptide treatment upregulated cerebral nuclear factor erythroid 2-related factor 2 and heme-oxygenase-1 and downregulated kelch-like ECH-associated protein 1 relative to untreated Alzheimer's disease model mice. Thus, the novel nanopeptide is expected to be used as the neuroprotective agent to prevent Alzheimer's disease.
Assuntos
Doença de Alzheimer , Nanopartículas Metálicas , Fármacos Neuroprotetores , Doença de Alzheimer/tratamento farmacológico , Animais , Antioxidantes/farmacologia , Modelos Animais de Doenças , Ouro/farmacologia , Camundongos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio , Zea maysRESUMO
Inflammation may be responsible for the development of premature rupture of membranes (PROM) including preterm PROM (PPROM) and mature PROM (MPROM). A total of four classic receptor proteins have been confirmed to assemble inflammasomes: NLR family pyrin domain containing (NLRP)1, NLRP3 and NLR family CARDdomain containing 4 (NLRC4) and absent in melanoma 2 (AIM2). The activation and expression of these receptormodulated inflammasomes in placenta and fetal membrane of PROM pregnancies requires investigation. In addition, a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4) is a risk factor for PROM, but whether its expression is associated with inflammasome activation remains to be elucidated. In the present study, the placenta and fetal membrane tissues of patients who had suffered PPROM and MPROM and healthy pregnancies were investigated. Reverse transcriptionquantitative PCR was used to determine the mRNA expression of inflammasomes and ADAMTS4. Western blotting, immunohistochemistry and ELISA were used to investigate the protein expression levels of inflammasomes and ADAMTS4. The results demonstrated that all four inflammasomes were elevated in placenta and fetal membrane of PPROMs as were mRNA and protein expression levels of IL18 and IL1ß (compared with controls). A further increase of inflammasomes and interleukins was observed in MPROMs compared with controls. Similar results were also observed in ADAMTS4 expression in PPROM and MPROM groups. However, immunohistochemistry results revealed no significant difference of inflammasome receptor expression in PPROMs compared with controls. Finally, a general positive correlation between ADAMTS4 and all four inflammasome receptors in placenta and fetal membrane of PPROMs and MPROMs was observed. The present study revealed that NLRP1, NLRP3, AIM2 and NLRC4 inflammasome activation in PROM was increased. Promoted ADAMTS4 level was further observed in PROM group and was significantly correlated with inflammasome expression. Inhibition of inflammasome activation may provide a therapeutic target for clinical PROM treatment.