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1.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(4): 432-437, 2024 Apr 15.
Artigo em Chinês | MEDLINE | ID: mdl-38632062

RESUMO

Objective: To probe into the effectiveness of vertical compression of locking plate combined with hollow screws in the treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures. Methods: The clinical data of 128 patients with Sanders type Ⅱ and Ⅲ calcaneal fractures who were admitted between March 2019 and April 2022 and met the selection criteria were retrospectively analyzed. Among them, 65 patients were treated with locking plate combined with hollow screw vertical compression (study group), and 63 patients were treated with simple locking plate (control group). There was no significant difference in baseline data between the two groups ( P>0.05), such as gender, age, fracture side and Sanders classification, cause of injury, time from injury to operation. The operation time, intraoperative blood loss, hospital stay, and fracture healing time were recorded and compared between the two groups. Before operation and at 12 months after operation, the American Orthopaedic Foot and Ankle Association (AOFAS) score (including total score, pain score, functional score, and alignment score) was used to evaluate the recovery of foot function, and imaging indicators such as calcaneal width, calcaneal height, calcaneal length, Böhler angle, and Gissane angle were measured on X-ray films. Results: All patients were followed up 12 months after operation. There was no significant difference in operation time, intraoperative blood loss, hospital stay, and fracture healing time between the two groups ( P>0.05). Poor wound healing occurred in 1 case in the study group and 2 cases in the control group. At 12 months after operation, there was no significant difference between the two groups in the pre- and post-operative difference of calcaneal length, calcaneal height, Gissane angle, and Böhler angle ( P>0.05). However, the pre- and post-operative difference in calcaneal width in the study group was significantly higher than that in the control group ( P<0.05). The pre- and post-operative difference of AOFAS total score in the study group was significantly higher than that in the control group ( P<0.05), and further analysis showed that the pre- and post-operative difference of pain and function scores in the study group were significantly higher than those in the control group ( P<0.05), while there was no significant difference in the pre- and post-operative difference of force score between the two groups ( P>0.05). Conclusion: Compared with simple locking plate treatment, the treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures with vertical compression of locking plate combined with hollow screws can more effectively improve the width of the subtalar calcaneal articular surface, avoid peroneal longus and brevis impingement, reduce pain, and increase the range of motion of the subtalar joint, and the effectiveness is better.


Assuntos
Traumatismos do Tornozelo , Calcâneo , Traumatismos do Pé , Fraturas Ósseas , Traumatismos do Joelho , Humanos , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Resultado do Tratamento , Fraturas Ósseas/cirurgia , Calcâneo/lesões , Dor
2.
Cell Tissue Bank ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489016

RESUMO

Demineralized bone matrix (DBM) has been regarded as an ideal bone substitute as a native carrier of bone morphogenetic proteins (BMPs) and other growth factors. However, the osteoinductive properties diverse in different DBM products. We speculate that the harvest origin further contributing to variability of BMPs contents in DBM products besides the process technology. In the study, the cortical bone of femur, tibia, humerus, and ulna from a signal donor were prepared and followed demineralizd into DBM products. Proteins in bone martix were extracted using guanidine-HCl and collagenase, respectively, and BMP-2 content was detected by sandwich enzyme-linked immunosorbent assay (ELISA). Variability of BMP-2 content was found in 4 different DBM products. By guanidine-HCl extraction, the average concentration in DBMs harvested from ulna, humerus, tibia, and femur were 0.613 ± 0.053, 0.848 ± 0.051, 3.293 ± 0.268, and 21.763 ± 0.344, respectively (p < 0.05), while using collagenase, the levels were 0.089 ± 0.004, 0.097 ± 0.004, 0.330 ± 0.012, and 1.562 ± 0.008, respectively (p < 0.05). In general, the content of BMP-2 in long bones of Lower limb was higher than that in long bones of upper limb, and GuHCl had remarkably superior extracted efficiency for BMP-2 compared to collagenase. The results suggest that the origin of cortical bones harvested to fabricate DBM products contribute to the variability of native BMP-2 content, while the protein extracted method only changes the measured values of BMP-2.

3.
Am J Chin Med ; 52(2): 453-469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38490806

RESUMO

Doxorubicin (DOX) is a powerful anthracycline antineoplastic drug used to treat a wide spectrum of tumors. However, its clinical application is limited due to cardiotoxic side effects. Astragaloside IV (AS IV), one of the major compounds present in aqueous extracts of Astragalus membranaceus, possesses potent cardiovascular protective properties, but the underlying molecular mechanisms are unclear. Thus, the aim of this study was to investigate the effect of AS IV on DOX-induced cardiotoxicity (DIC). Our findings revealed that DOX induced pyroptosis through the caspase-1/gasdermin D (GSDMD) and caspase-3/gasdermin E (GSDME) pathways. AS IV treatment significantly improved the cardiac function and alleviated myocardial injury in DOX-exposed mice by regulating intestinal flora and inhibiting pyroptosis; markedly suppressed the levels of cleaved caspase-1, N-GSDMD, cleaved caspase-3, and N-GSDME; and reversed DOX-induced downregulation of silent information regulator 1 (SIRT1) and activation of the NLR family pyrin domain containing 3 (NLRP3) inflammasome in mice. The SIRT1 inhibitor EX527 significantly blocked the protective effects of AS IV. Collectively, our results suggest that AS IV protects against DIC by inhibiting pyroptosis through the SIRT1/NLRP3 pathway.


Assuntos
Miócitos Cardíacos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Saponinas , Triterpenos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose/fisiologia , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Cardiotoxicidade/metabolismo , Caspase 3/metabolismo , Sirtuína 1/metabolismo , Gasderminas , Doxorrubicina/efeitos adversos , Caspase 1/metabolismo
4.
Sci Rep ; 14(1): 5867, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467756

RESUMO

To illustrate the surgical technique and explore clinical outcomes of the reconstruction for the malignant and metastatic bone tumour of proximal femur with metallic modular intercalary prosthesis. Sixteen patients who underwent modular intercalary prosthetic reconstruction after tumour resection were included from April 2012 and October 2020. Prosthesis and screws parameters, resected bone length and residual bone length, clinical outcomes and survivorship were analyzed. All patients were followed up for an average of 19 months (range 1-74). In our series, 12 patients died of the progression of the primary disease at the final follow-up. The cumulative survivorship since the treatment of proximal femoral metastasis was 78.6% (11 patients) at 6 months and 38.5% (5 patients) at 1 year. The mean MSTS score was 22.25 ± 4.55 among all patients. There were no cases of loosening or breakage of the prostheses, plates or screws, despite the various measurements of prostheses and residual bones. Modular intercalary prosthetic reconstruction was an effective method for malignant tumour of the proximal femur, including the advantages of providing early pain relief, quickly restoring postoperative function, required a short operation time, and preserving the adjacent joints.


Assuntos
Neoplasias Ósseas , Fêmur , Humanos , Resultado do Tratamento , Fêmur/patologia , Extremidade Inferior , Implantação de Prótese/métodos , Neoplasias Ósseas/patologia , Estudos Retrospectivos
5.
BMC Musculoskelet Disord ; 25(1): 141, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355520

RESUMO

BACKGROUND: Anemia is a common complication of total hip arthroplasty (THA). In this study, we evaluated the preoperative risk factors for postoperative anemia after THA and developed a nomogram model based on related preoperative and intraoperative factors. METHODS: From January 2020 to May 2023, 927 THA patients at the same medical center were randomly assigned to either the training or validation cohort. The correlation between preoperative and intraoperative risk factors and postoperative anemia after THA was evaluated using univariate and multivariate logistic regression analysis. A nomogram was developed using these predictive variables. The effectiveness and validation for the clinical application of this nomogram were evaluated using the concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA). RESULTS: Through univariate and multivariate logistic regression analysis, 7 independent predictive factors were identified in the training cohort: Lower body mass index (BMI), extended operation time, greater intraoperative bleeding, lower preoperative hemoglobin level, abnormally high preoperative serum amyloid A (SAA) level, history of cerebrovascular disease, and history of osteoporosis. The C-index of the model was 0.871, while the AUC indices for the training and validation cohorts were 84.4% and 87.1%, respectively. In addition, the calibration curves of both cohorts showed excellent consistency between the observed and predicted probabilities. The DCA curves of the training and validation cohorts were high, indicating the high clinical applicability of the model. CONCLUSIONS: Lower BMI, extended operation time, increased intraoperative bleeding, reduced preoperative hemoglobin level, elevated preoperative SAA level, history of cerebrovascular disease, and history of osteoporosis were seven independent preoperative risk factors associated with postoperative anemia after THA. The nomogram developed could aid in predicting postoperative anemia, facilitating advanced preparation, and enhancing blood management. Furthermore, the nomogram could assist clinicians in identifying patients most at risk for postoperative anemia.


Assuntos
Anemia , Artroplastia de Quadril , Transtornos Cerebrovasculares , Osteoporose , Humanos , Anemia/diagnóstico , Anemia/epidemiologia , Anemia/etiologia , Artroplastia de Quadril/efeitos adversos , Hemoglobinas , Nomogramas , Estudos Retrospectivos , Redução de Peso
6.
Adv Mater ; 36(14): e2309298, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146682

RESUMO

Solid-state sodium (Na) batteries (SSNBs) hold great promise but suffer from several major issues, such as high interfacial resistance at the solid electrolyte/electrode interface and Na metal dendrite growth. To address these issues, a piezoelectric interlayer design for an Na3Zr2Si2PO12 (NZSP) solid electrolyte is proposed herein. Two typical piezoelectric films, AlN and ZnO, coated onto NZSP function as interlayers designed to generate a local stress-induced field for alleviating interfacial charge aggregation coupling stress concentration and promoting uniform Na plating. The results reveal that the interlayer (ZnO) with matched modulus, high Na-adhesion, and sufficient piezoelectricity can provide a favorable interphase. Low interfacial resistances of 91 and 239 Ω cm2 are achieved for the ZnO layer at 30 and 0 °C, respectively, which are notably lower than those for bare NZSP. Moreover, steady Na plating/stripping cycles are rendered over 850 and 4900 h at 0 and 30 °C, respectively. The superior anodic performance is further manifested in an Na2MnFe(CN)6-based full cell which delivers discharge capacities of 125 mA h g-1 over 1600 cycles at 30 °C and 90 mA h g-1 over 500 cycles at 0 °C. A new interlayer-design insight is clearly demonstrated for SSNBs breaking low-temperature limits.

7.
PLoS One ; 18(12): e0295320, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38039290

RESUMO

OBJECTIVE: To investigate the associations of serum DNA methylation levels of chemokine signaling pathway genes with Alzheimer's disease (AD) and mild cognitive impairment (MCI) in elderly people in Xinjiang, China, and to screen out genes whose DNA methylation could distinguish AD and MCI. MATERIALS AND METHODS: 37 AD, 40 MCI and 80 controls were included in the present study. DNA methylation assay was done using quantitative methylation-specific polymerase chain reaction (qMSP). Genotyping was done using Sanger sequencing. RESULTS: DNA methylation levels of ADCY2, MAP2K1 and AKT1 were significantly different among AD, MCI and controls. In the comparisons of each two groups, AKT1 and MAP2K1's methylation was both significantly different between AD and MCI (p < 0.05), whereas MAP2K1's methylation was also significantly different between MCI and controls. Therefore, AKT1's methylation was considered as the candidate serum marker to distinguish AD from MCI, and its association with AD was independent of APOE ε4 allele (p < 0.05). AKT1 hypermethylation was an independent risk factor for AD and MAP2K1 hypomethylation was an independent risk factor for MCI in logistic regression analysis (p < 0.05). CONCLUSION: This study found that the serum of AKT1 hypermethylation is related to AD independently of APOE ε4, which was differentially expressed in the Entorhinal Cortex of the brain and was an independent risk factor for AD. It could be used as one of the candidate serum markers to distinguish AD and MCI. Serum of MAP2K1 hypomethylation is an independent risk factor for MCI.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/genética , Metilação de DNA , Apolipoproteína E4/genética , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/genética , Transdução de Sinais/genética , Quimiocinas/genética
8.
Medicine (Baltimore) ; 102(45): e35943, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37960744

RESUMO

To explore the early clinical value of enhanced recovery after surgery (ERAS) with interscalene brachial plexus block (ISB) for arthroscopic rotator cuff repair (ARCR). We enrolled 240 patients who underwent arthroscopic rotator cuff repair, randomly divided into 3 groups (n = 80 each). Groups A, B, and C underwent only surgery, surgery + ERAS, and ISB + surgery + ERAS, respectively. We analyzed the clinical data and postoperative indicators for the 3 patient groups. Group comparisons of clinical data and postoperative indicators revealed no significant differences in clinical characteristics (P > .05). Group C showed superior Visual Analog Scale scores at 0-6 and 6-24 hours postoperatively (P < .05), and the shortest length of hospital stay (LOS) (P < .05). At 6 weeks and 3 months postoperatively, Constant-Murley shoulder score and University of California-Los Angeles scores were better in Groups B and C than in Group A (P < .05). Joint swelling was more common in Group A than in Groups B and C (P < .05) but with no significant difference in the incidence of postoperative stiffness (P > .05). ERAS can relieve postoperative pain, shorten LOS, and help restore shoulder joint mobility, thereby reducing postoperative swelling. ISB + ERAS optimized pain control and allowed a shorter LOS, but had similar effects on early functional recovery and complications.


Assuntos
Bloqueio do Plexo Braquial , Lesões do Manguito Rotador , Humanos , Anestésicos Locais , Artroscopia/efeitos adversos , Bloqueio do Plexo Braquial/efeitos adversos , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/etiologia , Manguito Rotador/cirurgia , Lesões do Manguito Rotador/cirurgia , Lesões do Manguito Rotador/complicações , Resultado do Tratamento
9.
ACS Appl Mater Interfaces ; 15(42): 49321-49328, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37847183

RESUMO

Solid-state metal batteries with nonflammable solid-state electrolytes are regarded as the next generation of energy storage technology on account of their high safety and energy density. However, as for most solid electrolytes, low room temperature ionic conductivity and interfacial issues hinder their practical application. In this work, Na super ionic conductor (NASICON)-type Na3Zr2Si2PO12 (NZSP) electrolytes with improved ionic conductivity are synthesized by the NaBr-assisted sintering method. The effects of the NaBr sintering aid on the crystalline phase, microstructure, densification degree, and electrical performance as well as the electrochemical performances of the NZSP ceramic electrolyte are investigated in detail. Specifically, the NZSP-7%NaBr-1150 ceramic electrolyte has an ionic conductivity of 1.2 × 10-3 S cm-1 (at 25 °C) together with an activation energy of 0.28 eV. A low interfacial resistance of 35 Ω cm2 is achieved with the Na/NZSP-7%NaBr-1150 interface. Furthermore, the Na/NZSP-7%NaBr-1150/Na3V2(PO4)3 battery manifests excellent cycling stability with a capacity retention of 98% after 400 cycles at 1 C and 25 °C.

10.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(10): 1225-1229, 2023 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-37848317

RESUMO

Objective: To compare the effectiveness of subtalar arthroereisis (STA) combined with modified Kidner procedure versus STA alone in the treatment of flexible flatfoot combined with painful accessory navicular bone in children. Methods: The clinical data of 33 children with flexible flatfoot combined with painful accessory navicular bone who were admitted between August 2018 and August 2021 and met the selection criteria were retrospectively analyzed. They were divided into a combination group (17 cases, treated by STA combined with modified Kidner procedure) and a control group (16 cases, treated by STA alone) according to the surgical methods. There was no significant difference in baseline data between the two groups ( P>0.05), such as gender, age, affected side of the foot, disease duration, and preoperative visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, talus-first metatarsal angle (T1MT), talus-second metatarsal angle (T2MT), talonavicular coverage angle (TCA), talus first plantar angle (Meary angle), calcaneal inclination angle (Pitch angle), and heel valgus angle (HV). The operation time, incision length, intraoperative blood loss, number of intraoperative fluoroscopies, and perioperative complications were recorded in both groups. The anteroposterior, lateral, and calcaneal axial X-ray films for the affected feet were taken regularly, and T1MT, T2MT, TCA, Meary angle, Pitch angle, and HV were measured. The VAS score, AOFAS ankle-hindfoot score were used to evaluate pain and functional recovery before and after operation. Results: Surgeries in both groups were successfully performed without surgical complication such as vascular, nerve, or tendon injuries. Less operation time, shorter incision length, less intraoperative blood loss, and fewer intraoperative fluoroscopies were found in the control group than in the combination group ( P<0.05). One case in the combination group had partial necrosis of the skin at the edge of the incision, which healed after the dressing change and infrared light therapy, and the rest of the incisions healed by first intention. All children were followed up 12-36 months, with a mean of 19.6 months. At last follow-up, VAS score and AOFAS ankle-hindfoot score significantly improved in both groups when compared with preoperative ones ( P<0.05), and the differences of these scores between before and after operation improved more significantly in the combination group than in the control group ( P<0.05). Imaging results showed that the T1MT, T2MT, TCA, Meary angle, and HV significantly improved in both groups at last follow-up when compared with preoperative ones ( P<0.05), and the Pitch angle had no significant difference when compared with preoperative one ( P>0.05). But there was no significant difference in the difference of these indicators between before and after operation between the two groups ( P>0.05). Conclusion: Both procedures are effective in the treatment of flexible flatfoot children with painful accessory navicular bone. STA has the advantage of minimally invasive, while STA combined with modified Kidner procedure has better effectiveness.


Assuntos
Pé Chato , Tálus , Humanos , Criança , Pé Chato/cirurgia , Perda Sanguínea Cirúrgica , Estudos Retrospectivos , Resultado do Tratamento , Osteotomia/métodos , Dor
11.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(8): 945-951, 2023 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-37586793

RESUMO

Objective: To measure the concentration of bone morphogenetic protein 2 (BMP-2) in demineralized bone matrix (DBM) prepared from different long bones and to evaluate the osteoinductivity of different DBM on MC3T3-E1 cells. Methods: Different bones from the same cadaver donor were used as the initial materials for making DBM, which were divided into ulna group (uDBM), humerus group (hDBM), tibia group (tDBM), and femur group (fDBM) according to the origins, and boiled DBM (cDBM) was taken as the control group. The proteins of DBM were extracted by guanidine hydrochloride, and the concentrations of BMP-2 were determined by ELISA assay. Then the DBM were co-cultured with MC3T3-E1 cells, the proliferation of MC3T3-E1 cells was observed by cell counting kit 8 (CCK-8) assay. The osteogenic differentiation ability of MC3T3-E1 cells was qualitatively observed by alizarin red, alkaline phosphatase (ALP), and Van Gieson staining, and the osteogenic differentiation ability of MC3T3-E1 cells was quantitatively analyzed by ALP content. Linear regression was used to analyze the effect of BMP-2 concentration in DBM on ALP synthesis. Results: There were significant differences in the concentration of BMP-2 among the DBM groups (P<0.05). The concentrations of BMP-2 in the lower limb long bone were higher than those in the upper limb long bone, and the concentration of BMP-2 in the fDBM group was about 35.5 times that in the uDBM group. CCK-8 assay showed that the cells in each group continued to proliferate within 5 days of co-culture, and the absorbance (A) values at different time points were in the order of cDBM group

Assuntos
Proteína Morfogenética Óssea 2 , Osteogênese , Fosfatase Alcalina , Matriz Óssea , Contagem de Células , Corantes , Animais , Camundongos
12.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(8): 964-969, 2023 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-37586796

RESUMO

Objective: To study the effectiveness of TightRope elastic fixation combined with functional total repair of the inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury. Methods: The clinical data of 34 patients with distal tibiofibular syndesmosis injury who met the selection criteria between January 2020 and January 2022 were retrospectively analyzed, and they were divided into improved group (TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament) and control group (distal tibiofibular screw fixation) according to the surgical methods, with 17 cases in each group. There was no significant difference in age, gender, body mass index, fracture type, and other baseline data between the two groups (P>0.05). The operation time, intraoperative blood loss, and complications were recorded in the two groups. The American Orthopaedic Foot and Ankle Society (AOFAS) score, ankle metatarsal flexion and dorsal extension range of motion were used to evaluate the ankle function. The patient satisfaction survey was conducted at last follow-up. Results: All 34 patients were followed up 8-20 months, with a median of 13 months. The operation time and intraoperative blood loss in the improved group were significantly longer than that in the control group (P<0.05). In the improved group, no infection or poor reduction occurred, and only 1 patient had TightRope knot reaction at 6 months after operation. In the control group, there were 2 cases of poor reduction, 1 case of lower tibiofibular screw rupture, and 1 case of subcutaneous infection (cured after anti-infection treatment). There was no significant difference in the incidence of complications between the two groups (P>0.05). At last follow-up, the AOFAS score and ankle metatarsal flexion and dorsal extension range of motion of the improved group were significantly better than those of the control group (P<0.05). The satisfaction rates of patients in the improved group and the control group were 94.1% and 82.4%, respectively, showing significant difference (P<0.05). Conclusion: TightRope elastic fixation combined with functional total repair of inferior tibiofibular ligament in the treatment of distal tibiofibular syndesmosis injury has sufficient fixation strength, and can achieve better effectiveness and joint function compared with traditional screw fixation.


Assuntos
Traumatismos do Tornozelo , Articulação do Tornozelo , Procedimentos de Cirurgia Plástica , Humanos , Articulação do Tornozelo/cirurgia , Perda Sanguínea Cirúrgica , Ligamentos/lesões , Ligamentos/cirurgia , Estudos Retrospectivos , Traumatismos do Tornozelo/cirurgia
13.
Sci Adv ; 9(24): eadh0667, 2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37327333

RESUMO

Understanding how the charge travels through sequence-controlled molecules has been a formidable challenge because of simultaneous requirements in well-controlled synthesis and well-manipulated orientation. Here, we report electrically driven simultaneous synthesis and crystallization as a general strategy to study the conductance of composition and sequence-controlled unioligomer and unipolymer monolayers. The structural disorder of molecules and conductance variations on random positions can be extremely minimized, by uniform synthesis of monolayers unidirectionally sandwiched between electrodes, as an important prerequisite for the reproducible measurement on the micrometer scale. These monolayers show tunable current density and on/off ratios in four orders of magnitude with controlled multistate and massive negative differential resistance (NDR) effects. The conductance of monolayer mainly depends on the metal species in homo-metal monolayers, while the sequence becomes a matter in hetero-metal monolayers. Our work demonstrates a promising way to release an ultra-rich variety of electrical parameters and optimize the functions and performances of multilevel resistive devices.


Assuntos
Eletricidade , Alimentos , Cristalização , Eletrodos , Viagem
14.
Small ; 19(33): e2301230, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37081280

RESUMO

In this work, an efficient screening method to select appropriate sintering aids for a wide range of oxide material systems is developed. Consequently, Na2 B4 O7 , NaF, and CuO are selected as sintering aids for sodium super ionic conductor (NASICON)-type Na3 Zr2 Si2 PO12 ceramic to verify the feasibility of the as-proposed method. As evidenced by the results, the sinterability and densification of ceramic matrix are apparently improved. Specifically, Na3 Zr2 Si2 PO12 -7%Na2 B4 O7 , Na3 Zr2 Si2 PO12 -3%NaF, and Na3 Zr2 Si2 PO12 -3%CuO endow much higher room temperature ionic conductivity of 1.03 × 10-3 , 1.61 × 10-3 , and 1.63 × 10-3  S cm-1 , respectively, in comparison with the pristine (7.23 × 10-4  S cm-1 ). The underlying mechanism for the enhanced performance is also discussed. The symmetric sodium cells assembled with sintering aids modified Na3 Zr2 Si2 PO12 ceramic electrolyte exhibit ultra-stable metallic Na plating/stripping at room temperature. Moreover, solid-state sodium batteries paired with Na3 V1.5 Cr0.5 (PO4 )3 cathode active material and modified Na3 Zr2 Si2 PO12 ceramic electrolyte demonstrate superior cycling stability and excellent rate capability. Furthermore, an as-developed strategy can be universally extended to synthesize high-performance oxide ceramics.

15.
Cell Tissue Bank ; 24(1): 203-210, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35831637

RESUMO

At present, the commonly used allogeneic bone powder in the clinic can be divided into nondemineralized bone matrix and demineralized bone matrix (DBM). Commonly used demineralizers include acids and ethylene diamine tetraacetic acid (EDTA). There may be some diversities between them. Also, the size of the bone particle can affects its cell compatibility and osteogenic ability. We produced different particle sizes i.e., < 75, 75-100, 100-315, 315-450, 450-650, and 650-1000 µm, and treated in three ways (nondemineralized, demineralized by EDTA, and demineralized by HCl). Scanning electron microscopy showed that the surface of the samples in each group was relatively smooth without obvious differences. The results of specific surface area and porosity analysis showed that they were significantly higher in demineralized bone powder than in nondemineralized bone powder, however, there was no significant difference between the two decalcification methods. The content of hydroxyproline in nondemineralized bone powder and EDTA-demineralized bone powder had no statistical difference, while HCl-demineralization had statistical significance compared with the former two, and the content increased with the decrease of particle size. The protein and BMP-2 extracted from HCl demineralized bone powder were significantly higher than that from nondemineralized bone powder and EDTA demineralized bone powder, and there were differences among different particle sizes. These results suggested the importance of demineralization mode and particle size of the allogenic bone powder and provided guidance for the choice of the most appropriate particle size and demineralization mode to be used in tissue bioengineering.


Assuntos
Osso e Ossos , Transplante de Células-Tronco Hematopoéticas , Tamanho da Partícula , Pós/análise , Ácido Edético , Matriz Óssea/química , Osteogênese , Técnica de Desmineralização Óssea
16.
Angew Chem Int Ed Engl ; 62(4): e202216838, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36440880

RESUMO

The synthesis of crystalline polymer with a well-defined orientated state and a two-dimensional crystalline size beyond a micrometer will be essential to achieve the highest physical feature of polymer material but remain challenging. Herein, we show the synthesis of the crystalline unipolymer monolayer with an unusual ultrahigh modulus that is higher than the ITO substrate and high conductance by simultaneous electrosynthesis and manipulation. We find that the polymer monolayer has fully extended in the vertical and unidirectional orientation, which is proposed to approach their theoretically highest density, modulus, and conductivity among all aggregation formations of the current polymer. The modulus and current density can reach 40 and 1000 times higher than their amorphous counterpart. It is also found that these monolayers exhibit the bias- and length-dependent multiple charge states and asymmetrically negative differential resistance (NDR) effect, indicating that this unique molecular tailoring and ordering design is promising for multilevel resistive memory devices. Our work demonstrates the creation of a crystalline polymer monolayer for approaching the physical limit of polymer electronic materials and also provides an opportunity to challenge the synthetically iterative limit of an isolated ultra-long polymer.

17.
J Colloid Interface Sci ; 629(Pt A): 33-43, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36049327

RESUMO

Electrochemical urea oxidation reaction (UOR) is urgently in demand for diverse energy conversion and storage device coupled with pollution treatment because of its favorable thermodynamic potential (0.37 V vs RHE) and wide distribution nature of urea, but simultaneously gravely limited by the sluggish reaction dynamics and poisoning of catalyst. Herein, dual-phased Ni0.85Se/NiSe2 coupling with N doped carbon (Ni0.85Se/NiSe2@NC-2) in situ is prepared by a solvothermal-selenization pathway. Benefiting from the collective promotion of the dual-phased composition and the NC support, Ni0.85Se/NiSe2@NC provides abundant active sites, enhanced electrical conductivity. It delivers a current density of 252 mA cm-2 at 1.6 V vs RHE with a small Tafel slop of 64.4 mV dec-1 and gets a lower reaction barrier. Moreover, it requires a cell voltage of 1.46 V to approach 50 mA cm-2, about 250 mV less than that of water electrolysis, confirming the less energy consumption. Notably, the N doped carbon protects Ni0.85Se/NiSe2 nanocrystals from aggregation leading to a faster CO2 desorption from Ni sites, which endow the Ni0.85Se/NiSe2@NC-2 a much better working stability. The direct urea hydrogen peroxide fuel cell (DUHPFC) achieves a maximum power density of 9.09 mW cm-2 at 20 °C. This work extends highly efficient dual-phased structure loading in NC catalysts system for urea-assisted energy conversion.


Assuntos
Carbono , Níquel , Ureia , Peróxido de Carbamida , Dióxido de Carbono , Água
18.
J Chromatogr A ; 1681: 463455, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36075135

RESUMO

In this study, an expanded bed anion exchange in a countercurrent chromatography column (EB-CCC) technique for separation and purification of heparin, an anticoagulant and antithrombotic glycosaminoglycan, is reported for the first time. A comparative evaluation of the EB-CCC technique with the conventional fixed bed column chromatography (FBCC) revealed its effectiveness in improving adsorption at high flow rates and reducing separation time. A significantly higher maximum adsorption (91.66%) was exhibited by EB-CCC in comparison with FBCC (45.16%) at the eluent flow rate of 1 mL·min-1. Similarly, the experimental adsorption capacity of heparin was enhanced by 1.69, 2.06 and 2.58 times in the case of EB-CCC at the flow rates of 1, 2 and 5 mL·min-1, respectively. Moreover, the directly proportional amplification of double loaded resin and double column volume was demonstrated at an EB-CCC rotational speed of 300 rpm and a flow rate of 2 mL·min-1, and the experimental adsorption capacity was observed to increase from 66.42 to 136.48 mg·g-1 after amplification. Heparin purified by EB-CCC displayed higher potency (216.09 ± 11.89 IU·mg-1) as compared to FBCC (205.51 ± 7.90 IU·mg-1) and the initial crude heparin 134.17 ± 4.12 IU·mg-1. Furthermore, comparing to the purified heparin by FBCC, heparin purified by EB-CCC had low molecular weight, high FXa/FIIa, superior anticoagulation effect and enhanced suitability as an exogenous anticoagulant.


Assuntos
Distribuição Contracorrente , Heparina , Adsorção , Ânions , Anticoagulantes/farmacologia , Distribuição Contracorrente/métodos , Fibrinolíticos
19.
J Microbiol ; 60(11): 1095-1105, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36048328

RESUMO

Mycobacterium tuberculosis (M. tuberculosis) is a highly pathogenic intracellular pathogen that causes tuberculosis (TB), the leading cause of mortality from single infections. Redox homeostasis plays a very important role in the resistance of M. tuberculosis to antibiotic damage and various environmental stresses. The antioxidant sulforaphane (SFN) has been reported to exhibit anticancer activity and inhibit the growth of a variety of bacteria and fungi. Nonetheless, it remains unclear whether SFN exhibits anti-mycobacterial activity. Our results showed that the SFN against M. tuberculosis H37Ra exhibited bactericidal activity in a time and dose-dependent manner. The anti-tubercular activity of SFN was significantly correlated with bacterial reactive oxygen species (ROS) levels. In addition, SFN promoted the bactericidal effect of macrophages on intracellular bacteria in a dose-dependent manner, mediated by increasing intracellular mitochondrial ROS levels and decreasing cytoplasmic ROS levels. Taken together, our data revealed the previously unrecognized antimicrobial functions of SFN. Future studies focusing on the mechanism of SFN in macrophages against M. tuberculosis are essential for developing new host-directed therapeutic approaches against TB.


Assuntos
Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Humanos , Espécies Reativas de Oxigênio , Mycobacterium smegmatis
20.
Nano Lett ; 22(17): 7187-7194, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36018614

RESUMO

Severe challenges are restraining the practical application of solid-state batteries, such as the dendrite growth and unsatisfactory compatibility between solid electrolyte and electrode. Here, we propose an interface dynamic control (IDC) strategy to ensure the stable operation of NASICON-based solid-state sodium batteries. First, we introduce intergranular phase (CuO) to effectively promote the densification of Na3Zr2Si2PO12 with an optimized ionic conductivity of 1.74 × 10-3 S cm-1 at 25 °C. Moreover, the kinetically formed Na-Cu-O interlayer reveals outstanding conductive capability. The dramatically reduced interfacial area-specific resistance (70 ohm cm-2) boosts the resistance to Na dendrite growth, ensuring the excellent cycling stability of symmetric Na cells at a current density of 0.4 mA cm-2 and room temperature. All-solid-state sodium metal batteries with Na3V1.5Cr0.5(PO4)3 cathode and modified Na3Zr2Si2PO12 ceramic electrolyte reveal a high retention of 87.4% at 100 mA g-1 over 300 cycles. This work opens up a new route for the rational interface design of NASICON-structure solid electrolyte toward the application in the high energy-density and high safety electrochemical energy storage devices.

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