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1.
Chemphyschem ; 25(5): e202300732, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38146966

RESUMO

Catalytic conversion of hydrogen sulfide (H2 S) plays a vital role in environmental protection and safety production. In this review, recent theoretical advances for catalytic conversion of H2 S are systemically summarized. Firstly, different mechanisms of catalytic conversion of H2 S are elucidated. Secondly, theoretical studies of catalytic conversion of H2 S on surfaces of metals, metal compounds, and single-atom catalysts (SACs) are systematically reviewed. In the meantime, various strategies which have been adopted to improve the catalytic performance of catalysts in the catalytic conversion of H2 S are also reviewed, mainly including facet morphology control, doped heteroatoms, metal deposition, and defective engineering. Finally, new directions of catalytic conversion of H2 S are proposed and potential strategies to further promote conversion of H2 S are also suggested: including SACs, double atom catalysts (DACs), single cluster catalysts (SCCs), frustrated Lewis pairs (FLPs), etc. The present comprehensive review can provide an insight for the future development of new catalysts for the catalytic conversion of H2 S.

2.
Eur Spine J ; 33(1): 298-306, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37659047

RESUMO

PURPOSE: The objective of this study was to investigate the optimal entry point and pedicle camber angle for L5 pedicle screws of different canal types. METHODS: CT imaging data were processed by Mimics for simulated pedicle screw placement, and PD (Pedicle diameter), PCA (Pedicle camber angle), LD (Longitudinal distance), TD (Transverse distance), and PBG (Pedicle screw breach grade) were measured. Then they were divided into the Round group and Trefoil group according to the type of spinal canal. When comparing PD, PCA, LD, TD, and PBG, the two sides of the pedicle were compared separately, so they were first divided into the round-type pedicle group and the trefoil-type pedicle group. RESULTS: In the round-type pedicle group (n = 134) and the trefoil-type pedicle group (n = 264), there was no significant difference in PD and LD, but there was a significant difference in PCA between the two groups (t = - 4.072, P < 0.05). A statistically significant difference in the distance of the Magerl point relative to the optimal entry point (t = - 3.792, P < 0.05), and the distance of the Magerl point relative to the optimal entry point was greater in the trefoil-type pedicle group than in the round-type pedicle group. CONCLUSION: The optimal entry point for L5 is more outward than the Magerl point, and the Trefoil spinal canal L5 is more outwardly oriented than the Round spinal canal L5, with a greater angle of abduction during pedicle screw placement.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Estudos Retrospectivos , Fusão Vertebral/métodos , Canal Medular/diagnóstico por imagem , Canal Medular/cirurgia , Tomografia Computadorizada por Raios X
3.
Phys Chem Chem Phys ; 25(44): 30663-30669, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37933587

RESUMO

MnO2 is an oxide with many crystalline phases and is often used as a cathode material for aqueous zinc-ion batteries. However, its poor electrical conductivity and structural instability limit its further application. In the present work, Mo-doped MnO2 microflowers are successfully prepared by a facile hydrothermal method. Interestingly, it is found that the doping of Mo inhibits the phase transition from δ-MnO2 to α-MnO2, which may be related to the low crystallinity of Mo doped MnO2. Compared with undoped MnO2, Mo-doped MnO2 maintains two-dimensional morphology with a large specific surface area and mesoporous structure. In addition, the electronic conductivity and reversibility of Zn2+ insertion/extraction are improved in Mo doped MnO2. Therefore, Mo-doped MnO2 exhibits high reversible capacity and long cycling stability. For example, a high reversible capacity of 72.6 mA h g-1 can be achieved at a current density of 2000 mA g-1 after 2500 cycles.

4.
BMC Musculoskelet Disord ; 24(1): 588, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37464358

RESUMO

BACKGROUND: Hip fractures are still unsolved problems nowadays. We evaluated the functional outcomes and complications in the treatment of hip fractures (AO/OTA31A1-A3) to find potential difference and risk between intramedullary nail (IMN) and dynamic hip screw (DHS). METHOD: We searched PubMed, Embase, Cochrane library up to 19 June 2023 and retrieved any studies comparing IMN and DHS in treatment of Hip fractures. The main outcomes and complications were extracted from the included studies. The fixed-effect model was selected to pool the data for homogeneous studies (I2 < 50%). Otherwise, the random effects model was selected (heterogeneity, I2 > 50%). The analysis of sensitivity and subgroup was performed to explore the homogeneous studies among studies. The p-value of less than 0.05 was considered statistically significant. RESULTS: 30 RCT studies were included in this meta-analysis. There were significant difference of in the items of blood loss, screening time, femoral neck shortening, non-union, and femoral fractures (p < 0.05). Significant difference was found in the parameter of open reduction of fracture after sensitive analysis (p < 0.05). No significant difference was found in the parameter of Mobility Score at the last follow-up after sensitive analysis (p ≥ 0.05). There was no significant difference in the parameters of open reduction of fracture, required blood transfusion, mean surgical time, hospital stays, time to healing, mean Harris Hip Score, infection, cut out, poor reduction, breakage of implant, failure of fixation, reoperation, and systemic complications of chest infection, decubital ulcer, urinary tract infection and persistent pain in the hip (p ≥ 0.05). CONCLUSIONS: Our meta-analysis revealed that hip fractures treated with IMN have merits with lower rate of blood loss, femoral neck shortening and non-union; shortcoming of increased risk of femoral fractures. It is suggested that special attention should be paid to the risk of femoral fracture when intramedullary nail was inserted in the intraoperative.


Assuntos
Fraturas do Fêmur , Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Pinos Ortopédicos , Fixação Intramedular de Fraturas/efeitos adversos , Parafusos Ósseos , Fixação Interna de Fraturas/efeitos adversos , Fraturas do Quadril/cirurgia , Fraturas do Quadril/etiologia , Fraturas do Fêmur/etiologia , Resultado do Tratamento
5.
Sensors (Basel) ; 23(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765949

RESUMO

The self-reconfigurable modular robotic system is a class of robots that can alter its configuration by rearranging the connectivity of their component modular units. The reconfiguration deformation planning problem is to find a sequence of reconfiguration actions to transform one reconfiguration into another. In this paper, a hybrid reconfiguration deformation planning algorithm for modular robots is presented to enable reconfiguration between initial and goal configurations. A hybrid algorithm is developed to decompose the configuration into subconfigurations with maximum commonality and implement distributed dynamic mapping of free vertices. The module mapping relationship between the initial and target configurations is then utilized to generate reconfiguration actions. Simulation and experiment results verify the effectiveness of the proposed algorithm.

6.
Sensors (Basel) ; 23(15)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37571736

RESUMO

This paper focuses on motion planning for mobile manipulators, which includes planning for both the mobile base and the manipulator. A hierarchical motion planner is proposed that allows the manipulator to change its configuration autonomously in real time as needed. The planner has two levels: global planning for the mobile base in two dimensions and local planning for both the mobile base and the manipulator in three dimensions. The planner first generates a path for the mobile base using an optimized A* algorithm. As the mobile base moves along the path with the manipulator configuration unchanged, potential collisions between the manipulator and the environment are checked using the environment data obtained from the on-board sensors. If the current manipulator configuration is in a potential collision, a new manipulator configuration is searched. A sampling-based heuristic algorithm is used to effectively find a collision-free configuration for the manipulator. The experimental results in simulation environments proved that our heuristic sampling-based algorithm outperforms the conservative random sampling-based method in terms of computation time, percentage of successful attempts, and the quality of the generated configuration. Compared with traditional methods, our motion planning method could deal with 3D obstacles, avoid large memory requirements, and does not require a long time to generate a global plan.

7.
Sensors (Basel) ; 23(17)2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37687903

RESUMO

Robot measurement systems with a binocular planar structured light camera (3D camera) installed on a robot end-effector are often used to measure workpieces' shapes and positions. However, the measurement accuracy is jointly influenced by the robot kinematics, camera-to-robot installation, and 3D camera measurement errors. Incomplete calibration of these errors can result in inaccurate measurements. This paper proposes a joint calibration method considering these three error types to achieve overall calibration. In this method, error models of the robot kinematics and camera-to-robot installation are formulated using Lie algebra. Then, a pillow error model is proposed for the 3D camera based on its error distribution and measurement principle. These error models are combined to construct a joint model based on homogeneous transformation. Finally, the calibration problem is transformed into a stepwise optimization problem that minimizes the sum of the relative position error between the calibrator and robot, and analytical solutions for the calibration parameters are derived. Simulation and experiment results demonstrate that the joint calibration method effectively improves the measurement accuracy, reducing the mean positioning error from over 2.5228 mm to 0.2629 mm and the mean distance error from over 0.1488 mm to 0.1232 mm.

8.
Sensors (Basel) ; 22(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35632338

RESUMO

This paper presents an innovative application of a 6-DOF robot in the field of rehabilitation training. This robot operates in a parallel fashion for lower limb movement, which adopts a new structure that can help patients to carry out a variety of rehabilitation exercises. Traditional parallel robots, such as the Stewart robot, have the characteristics of strong bearing capacity. However, it is difficult to achieve high-speed, high-acceleration and long journey movement. This paper presents a new robot configuration that can address these problems. This paper also conducts an all-around characteristic analysis of this new parallel robot, including kinematics, dynamics and structure, to better study the robot and improve its performance. This paper optimizes an algorithm to make it more suitable for rehabilitation training. Finally, the performance improvements brought by optimization are verified by simulations.


Assuntos
Robótica , Fenômenos Biomecânicos , Terapia por Exercício , Humanos , Extremidade Inferior , Movimento
9.
BMC Immunol ; 22(1): 36, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082709

RESUMO

BACKGROUND: Some long-term non-progressors (LTNPs) have decreasing CD4+ T cell counts and progress to AIDS. Exploring which subsets of CD4+ T cell decreasing and the determinants associated with the decay in these patients will improve disease progression surveillance and provide further understanding of HIV pathogenesis. METHODS: Twenty-five LTNPs infected with HIV by blood products were classified as decreased (DG) if their CD4+ cell count dropped to < 400 cells/µL during follow-up or as non-decreased (non-DG) if their CD4+ cell count was ≥400 cells/µL. Laboratory and clinical assessments were conducted at 6 consecutive visits to identify DG characteristics. RESULTS: The LTNPs were infected with HIV for 12 (IQR: 11.5-14) years, and 23 were classified as the B' subtype. Six individuals lost LTNP status 14.5 (IQR: 12.5-17.5) years after infection (DG), and the CD4+ T cell count decreased to 237 (IQR: 213-320) cells/µL at the latest visit. The naïve CD4+ T cell count decrease was greater than that of memory CD4+ T cells [- 128 (IQR: - 196, - 107) vs - 64 (IQR: - 182, - 25) cells/µL)]. Nineteen individuals retained LTNP status (non-DG). At enrolment, the viral load (VL) level (p = 0.03) and CD8+CD38+ percentage (p = 0.03) were higher in DG than non-DG individuals. During follow-up, viral load and CD8+CD38+ percentage were significantly increased and negatively associated with CD4+ cell count [(r = - 0.529, p = 0.008), (r = - 0.476, p = 0.019), respectively]. However, the CD8+CD28+ percentage and B cell count dropped in DG and were positively correlated with CD4+ T cell count [(r = 0.448, p = 0.028), (r = 0.785, p < 0.001)]. CONCLUSION: Immunological progression was mainly characterized by the decrease of naïve CD4+ T cell in LTNPs infected with HIV by blood products and it may be associated with high HIV RNA levels.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por HIV/imunologia , Paciente HIV Positivo não Progressor , HIV-1/fisiologia , Células T de Memória/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Estudos de Coortes , Progressão da Doença , Seguimentos , Infecções por HIV/transmissão , Humanos , Ativação Linfocitária , Contagem de Linfócitos , Masculino , Carga Viral
10.
BMC Musculoskelet Disord ; 22(1): 682, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34384390

RESUMO

BACKGROUND: Little information was obtained from the published papers about the kinematic coupling effect between tarsal bones during Ponseti manipulation. The aim was to explore the kinematic coupling effect of the joints around talus, to investigate the kinematic rhythm and coupling relationship of tarsal joints; to clarify the pulling effect on medial ligament of the ankle during the process of Ponseti manipulation. METHODS: The model of foot and ankle was reconstructed from the Chinese digital human girl No.1 (CDH-G1) image database. Finite element analysis was applied to explore the kinematic coupling effect of the joints around talus. The distal tibia and fibula bone and the head of talus were fixed in all six degrees of freedom; outward pressure was added to the first metatarsal head to simulate the Ponseti manipulation. Kinematic coupling of each tarsal joint was investigated using the method of whole model splitting, and medial ligament pulling of the ankle was studied by designing the model of medial ligament deletion during the Ponseti manipulation. RESULTS: All the tarsal joints produced significant displacement in kinematic coupling effect, and the talus itself produced great displacement in the joint of ankle. Quantitative analysis revealed that the maximum displacement was found in the joints of talonavicular (12.01mm), cuneonavicular (10.50mm), calcaneocuboid (7.97mm), and subtalar(6.99mm).The kinematic coupling rhythm between talus and navicular, talus and calcaneus, calcaneus and cuboid, navicular and cuneiform 1 were 1:12, 1:7, 1:2 and 1:1.6. The results of ligaments pulling showed that the maximum displacement was presented in the ligaments of tibionavicular (mean 27.99mm), talonavicular (21.03mm), and calcaneonavicular (19.18 mm). CONCLUSIONS: All the tarsal joints around talus were involved in the process of Ponseti manipulation, and the strongest kinematic coupling effect was found in the joints of talonavicular, subtalar, calcaneocuboid, and cuneonavicular. The ligaments of tibionavicular, talonavicular, and calcaneonavicular were stretched greatly. It was suggested that the method of Ponseti management was a complex deformity correction processes involved all the tarsal joints. The present study contributed to better understanding the principle of Ponseti manipulation and the pathoanatomy of clubfoot. Also, the importance of cuneonavicular joint should be stressed in clinical practice.


Assuntos
Tálus , Articulações Tarsianas , Articulação do Tornozelo , Fenômenos Biomecânicos , Feminino , Análise de Elementos Finitos , Humanos
11.
J Pediatr Orthop ; 40(1): 29-35, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31815859

RESUMO

BACKGROUND: The prevention and treatment of relapsed clubfoot remained challenging tasks. There were controversies as to treatment options and management, such as complete subtalar release, application of an Ilizarov external frame, or repeated Ponseti method; and different options were available in different treatment centers. This study was designed to evaluate the clinical outcome of relapsed clubfeet treated by repeated Ponseti method in comparison with the cases without relapse in term of gait analysis and to clarify the clinical efficacy of repeated Ponseti method in treating the relapsed clubfeet. METHODS: Thirty-seven patients (53 feet) were retrospectively identified from our database according to the inclusion and exclusion criteria. Among the 37 patients, 17 cases (25 relapsed clubfeet) were assigned to group I, whereas 20 cases (28 clubfeet without relapse) were assigned to group II. Clinical examination, gait analysis, and kinematic gait deviation criteria from Texas Scottish Rite Hospital for Children were used for evaluation. RESULTS: There was statistically significant difference in the parameters of foot length, stride length, and single limb support time (%gait cycle) between the 2 groups (P<0.05). No statistically significant difference was found in the kinematic parameters of total hip, knee, and ankle excursion, peak knee and ankle flexion and extension, and internal foot progression (P>0.05). There was no statistically significant difference in peak hip, knee, and ankle flexion moment, peak knee valgus moment, and peak ankle power (P>0.05). No statistically significant difference was found in equinus and calcaneus gait, increased ankle dorsiflexion, foot drop, and internal foot progression angle (P>0.05). CONCLUSIONS: Repeated Ponseti method for relapsed clubfeet can yield good or excellent clinical results. We recommend repeated Ponseti method as the treatment choice for relapsed clubfeet in the early stage. LEVEL OF EVIDENCE: Level III-retrospective comparative study.


Assuntos
Articulação do Tornozelo/fisiopatologia , Pé Torto Equinovaro/fisiopatologia , Pé Torto Equinovaro/terapia , Pé/fisiopatologia , Articulação do Joelho/fisiopatologia , Fenômenos Biomecânicos , Moldes Cirúrgicos , Feminino , Análise da Marcha , Articulação do Quadril/fisiopatologia , Humanos , Lactente , Recém-Nascido , Masculino , Manipulação Ortopédica , Amplitude de Movimento Articular , Recidiva , Retratamento , Estudos Retrospectivos , Resultado do Tratamento
12.
Sensors (Basel) ; 20(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992888

RESUMO

In manufacturing, traditional task pre-programming methods limit the efficiency of human-robot skill transfer. This paper proposes a novel task-learning strategy, enabling robots to learn skills from human demonstrations flexibly and generalize skills under new task situations. Specifically, we establish a markerless vision capture system to acquire continuous human hand movements and develop a threshold-based heuristic segmentation algorithm to segment the complete movements into different movement primitives (MPs) which encode human hand movements with task-oriented models. For movement primitive learning, we adopt a Gaussian mixture model and Gaussian mixture regression (GMM-GMR) to extract the optimal trajectory encapsulating sufficient human features and utilize dynamical movement primitives (DMPs) to learn for trajectory generalization. In addition, we propose an improved visuo-spatial skill learning (VSL) algorithm to learn goal configurations concerning spatial relationships between task-relevant objects. Only one multioperation demonstration is required for learning, and robots can generalize goal configurations under new task situations following the task execution order from demonstration. A series of peg-in-hole experiments demonstrate that the proposed task-learning strategy can obtain exact pick-and-place points and generate smooth human-like trajectories, verifying the effectiveness of the proposed strategy.


Assuntos
Aprendizado de Máquina , Movimento , Robótica , Algoritmos , Humanos
13.
Sensors (Basel) ; 20(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899335

RESUMO

In order to analyze the complex interactive behaviors between the robot and two humans, this paper presents an adaptive optimal control framework for human-robot-human physical interaction. N-player linear quadratic differential game theory is used to describe the system under study. N-player differential game theory can not be used directly in actual scenerie, since the robot cannot know humans' control objectives in advance. In order to let the robot know humans' control objectives, the paper presents an online estimation method to identify unknown humans' control objectives based on the recursive least squares algorithm. The Nash equilibrium solution of human-robot-human interaction is obtained by solving the coupled Riccati equation. Adaptive optimal control can be achieved during the human-robot-human physical interaction. The effectiveness of the proposed method is demonstrated by rigorous theoretical analysis and simulations. The simulation results show that the proposed controller can achieve adaptive optimal control during the interaction between the robot and two humans. Compared with the LQR controller, the proposed controller has more superior performance.


Assuntos
Teoria dos Jogos , Robótica , Algoritmos , Simulação por Computador , Humanos
14.
Sensors (Basel) ; 20(13)2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32630755

RESUMO

As there come to be more applications of intelligent robots, their task object is becoming more varied. However, it is still a challenge for a robot to handle unfamiliar objects. We review the recent work on the feature sensing and robotic grasping of objects with uncertain information. In particular, we focus on how the robot perceives the features of an object, so as to reduce the uncertainty of objects, and how the robot completes object grasping through the learning-based approach when the traditional approach fails. The uncertain information is classified into geometric information and physical information. Based on the type of uncertain information, the object is further classified into three categories, which are geometric-uncertain objects, physical-uncertain objects, and unknown objects. Furthermore, the approaches to the feature sensing and robotic grasping of these objects are presented based on the varied characteristics of each type of object. Finally, we summarize the reviewed approaches for uncertain objects and provide some interesting issues to be more investigated in the future. It is found that the object's features, such as material and compactness, are difficult to be sensed, and the object grasping approach based on learning networks plays a more important role when the unknown degree of the task object increases.

15.
Environ Sci Technol ; 53(12): 7095-7102, 2019 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-31124657

RESUMO

Bisphenol A (BPA) is an important endocrine disrupting chemical. Although high levels of BPA in some new clothes have been reported, the occurrence of bisphenol chemicals including BPA in daily clothes is still unknown, and the human exposure to BPA in clothes has not been well assessed. In this study, used/washed clothes were collected from residents' wardrobes and the concentrations of BPA and its analogues were detected. BPA was present in all the used clothes at concentrations ranging from <3.30 to 471 ng/g (median: 34.2 ng/g; mean ± SD: 57.5 ± 93.6 ng/g), while bisphenol S was also detected in 29% of the samples. Although higher average concentration (88.4 ± 289 ng/g) and maximum concentration (1823 ng/g) of BPA were found in the new clothes, the median concentration of BPA in the used clothes (34.2 ng/g) was even higher than that in the new clothes (17.7 ng/g). Cross contamination of BPA during laundering was identified by a simulated laundry experiment, which explained the homogenizing tendency of bisphenol contaminants in the used clothes. An estimated dermal exposure dose of 52.1 ng/kg BW/d was obtained for BPA exposure in children from the highly polluted sweaty clothes (with BPA concentration of 199 ng/g). This indicates a relatively high exposure risk in humans. Compared to other exposure routes, the contribution of dermal exposure dose of BPA from the daily clothes should not be neglected.


Assuntos
Compostos Benzidrílicos , Lavanderia , Criança , Humanos , Fenóis
16.
Sensors (Basel) ; 19(2)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634579

RESUMO

In this study, dual-modal fluorescence and photoacoustic microscopy was performed for noninvasive and functional in vivo imaging of inflammation induced by green fluorescent protein (GFP) transfected bacteria in mice ear. Our imaging results demonstrated that the multimodal imaging technique is able to monitor the tissue immunovascular responses to infections with molecular specificity. Our study also indicated that the combination of photoacoustic and fluorescence microscopy imaging can simultaneously track the biochemical changes including the bacterial distribution and morphological change of blood vessels in the biological tissues with high resolution and enhanced sensitivity. Consequently, the developed method paves a new avenue for improving the understanding of the pathology mechanism of inflammation.


Assuntos
Orelha/microbiologia , Inflamação/diagnóstico por imagem , Microscopia de Fluorescência/métodos , Técnicas Fotoacústicas/métodos , Animais , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/microbiologia , Orelha/diagnóstico por imagem , Orelha/patologia , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Humanos , Inflamação/microbiologia , Inflamação/patologia , Camundongos , Imagem Multimodal
17.
Angew Chem Int Ed Engl ; 58(36): 12415-12419, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31309679

RESUMO

Copper enrichment in the brain is highly related to Alzheimer's disease (AD) pathogenesis, but in vivo tracing of Cu2+ in the brain by imaging techniques is still a great challenge. In this work, we developed a series of activatable photoacoustic (PA) probes with low molecular weights (less than 438 Da), RPS1-RPS4, which can specifically chelate with Cu2+ to form radicals with turn-on PA signals in the near-infrared (NIR) region. Introducing the electron-donating group N,N-dimethylaniline into the probe was found to significantly enhance the radical stability and PA intensity. The best probe in the series, RPS1, showed a fast response (within seconds) to Cu2+ with high selectivity and a low PA detection limit of 90.9 nm. Owing to the low molecular weight and amphiphilic structure, RPS1 could effectively cross the blood-brain barrier (BBB) and thus allowed us, for the first time, to visualize Cu2+ in vivo via PA imaging in the brains of AD mice.


Assuntos
Doença de Alzheimer/metabolismo , Barreira Hematoencefálica/metabolismo , Cobre/análise , Cobre/metabolismo , Modelos Animais de Doenças , Sondas Moleculares/química , Técnicas Fotoacústicas/métodos , Doença de Alzheimer/patologia , Animais , Transporte Biológico , Camundongos
18.
IUBMB Life ; 70(6): 468-478, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29676845

RESUMO

The miR-490-3p was transfected into HepG2 cells to explore the correlation between miR-490-3p and hepatocellular carcinoma cell proliferation, apoptosis, and autophagy and its downstream target gene ATG7. Then we could possibly provide a mechanism for the treatment of hepatocellular carcinoma. MiR-490-3p was screened out by fold change > 4 and P < 0.01 using gene microarray data. The expression level of miR-490-3p was tested by qRT-PCR and the prognosis analysis was achieved by using TCGA data. The cell proliferation was tested via colony formation assay and CCK-8 after the miR-490-3p mimics were transfected into HepG2 cells; the variations of cell cycle and apoptosis was examined by flow cytometry assay; the number of autophagosome was observed by electron microscopy and the changes of autophagy-relative protein LC-II and LC-I as well as their ratio was tested by western blot. MiR-490-3p is low expressed in hepatocellular carcinoma cell lines and tissues. The results of TCGA showed that miR-490-3p high expression indicated better prognosis. After HepG2 cells were transfected with miR-490-3p mimics, cell viability was increased, cell proliferation was enhanced, cell cycle was blocked in G0/G1 phase, cell apoptosis rate was increased, the number of autophagosomes was reduced, autophagy-associated protein LC-II was decreased, and LC-I was increased and their ratio was decreased. After 3-MA was added, cell proliferation was declined, cell apoptosis rate was increased. Besides, the autophagy was inhibited by knocking down the ATG7, which promoted the cell apoptosis. MiR-490-3p could suppress cell proliferation, retard cell cycle and upgrade cell apoptosis by inhibiting autophagy in HCC cells via targeting ATG7. © 2018 IUBMB Life, 70(6):468-478, 2018.


Assuntos
Proteína 7 Relacionada à Autofagia/metabolismo , Autofagia , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Apoptose , Proteína 7 Relacionada à Autofagia/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Ciclo Celular , Proliferação de Células , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Prognóstico , Transdução de Sinais , Células Tumorais Cultivadas
19.
Acta Orthop ; 89(6): 662-667, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334643

RESUMO

Background and purpose - There are still controversies as to the age for beginning treatment with the Ponseti method. We evaluated the clinical outcome with different age at onset of Ponseti management for clubfoot. Patients and methods - 90 included children were divided into 3 groups in terms of age at start of treatment. The difference in treatment-related and prognosis-related variables including presentation age, initial Pirani and Dimeglio score, casts required, relapse rates, final Dimeglio score, and international clubfoot study group score (ICFSG) was analyzed. Results - Age between 28 days and 3 months at start of treatment method was associated with fewer casts required, lower relapse rate, and lower final ICFSG score (p < 0.05). Early treatment before 28 days of age required more casts and had a higher relapse rate (p < 0.05). The highest ICFSG scores were found in the ages between 3 and 6 months (p < 0.05). After propensity score matching, age between 28 days and 3 months was demonstrated to have a lower finial ICFSG score. Linear regression models showed that presentation age was positively correlated with final ICFSG score, and was identified as the only independent prognostic risk factor. Interpretation - There was lower rate of relapse and better clinical outcome when treatment was initiated at age between 28 days and 3 months. With the Ponseti method, clubfeet may not need urgent treatment.


Assuntos
Pé Torto Equinovaro/terapia , Procedimentos Ortopédicos/métodos , Tendão do Calcâneo/cirurgia , Fatores Etários , Análise de Variância , Braquetes , Moldes Cirúrgicos , Protocolos Clínicos , Terapia Combinada , Desenho de Equipamento , Seguimentos , Humanos , Lactente , Recém-Nascido , Recidiva , Estudos Retrospectivos , Tenotomia/métodos
20.
Chemistry ; 23(64): 16312-16318, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28929599

RESUMO

Although lithium-sulfur (Li-S) batteries are among the most promising rechargeable batteries in the field of energy-storage devices, their poor cycling performance restricts their potential applications. Polar materials can improve the cycling stability owing to their inherent strong chemical interaction with polysulfides. Herein, novel rutile TiO2 mesocrystals (RTMs) are employed as the host for sulfur in Li-S batteries; the RTMs display a stable cycling performance with a capacity retention of 64 % and a small average capacity decay rate of 0.12 % per cycle over 300 cycles at 1 C rate. The good electrochemical properties are attributed to the interior ordered nanopores of the RTMs, which can effectively limit the dissolution of polysulfides, and the ultrafine nanowires in RTMs, which shorten the path for lithium-ion transport effectively.

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