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1.
Chirality ; 36(2): e23638, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38384151

RESUMO

Chiral pesticides have the special chiral structures, so enantioselective biological effects are usually observed in living organisms. Current study used paclobutrazol as a case study and explored the enantioselective degradation and oxidative stress effect on wheat. The results demonstrated that the degradation of R-paclobutrazol was faster than S-paclobutrazol significantly and improved the content of MDA and O2 - in wheat plants, which proved that the R-paclobutrazol induced oxidative damage in wheat, showing selective biological effects, and S-paclobutrazol was friendly to wheat. This study provided a theoretical basis for the selective activity of chiral pesticides and the development of chiral pesticide monomers.


Assuntos
Praguicidas , Triazóis , Triticum , Triticum/metabolismo , Estereoisomerismo , Praguicidas/química , Estresse Oxidativo
2.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258930

RESUMO

Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid-glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition.

3.
Chemphyschem ; 24(17): e202300159, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37349282

RESUMO

Fluorescence imaging is conducive to establish a bridge between molecular biology and clinical medicine, and provides new tools for disease process research, early diagnosis, and efficacy evaluation, because of the advantages of rapid imaging and nondestructive detection. Herein, a series of fluorescent molecules with thiadiazole, or thiazole, or benzothiazole cores were designed and synthesized to develop more excellent fluorescent molecules in bio-imaging. According to theoretical and experimental methods, we found that benzothiazole derivative 14 B with conjugate expansion by (4-aminophenyl) ethynyl group was the most excellent fluorescent molecule among all the investigated compounds and exhibited low cytotoxicity and strong blue and green fluorescence by confocal cell imaging.


Assuntos
Benzotiazóis , Tiadiazóis , Benzotiazóis/química , Corantes , Fluorescência , Corantes Fluorescentes/química
4.
Adv Sci (Weinh) ; 10(22): e2301053, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37211705

RESUMO

Most metals and alloys suffer from high friction and wear due to their low hardness and lack of self-lubrication. Although plenty of strategies have been proposed, it is still a long-standing challenge to achieve diamond-like wear in metals. Metallic glasses (MGs) are supposed to possess low coefficient of friction (COF) because of their high hardness and fast surface mobility. However, their wear rate is larger than that of diamond-like materials. Here, this work reports the discovery of Ta-rich MGs that exhibit diamond-like wear. This work develops an indentation approach for high-throughput characterization of crack resistance. By employing deep indentation loading, this work is able to efficiently identify the alloys that exhibit better plasticity and crack resistance according to the differences of indent morphology. With high temperature stability, high hardness, improved plasticity, and crack resistance, the discovered Ta-based MGs exhibit diamond-like tribological properties, featured by COF as low as ≈0.05 for diamond ball test and ≈0.15 for steel ball test, and specific wear rate of only ≈10-7 mm3 N- 1 m-1 . The discovery approach and the discovered MGs exemplifie the promise to substantially reduce friction and wear of metals and may unleash the potential of MGs in tribological applications.

5.
Cardiovasc Diagn Ther ; 13(1): 67-82, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36864974

RESUMO

Acupuncture has already been extensively utilized to treat high blood pressure (hypertension) in several nations. Nevertheless, the bibliometric research on the worldwide usage of acupuncture for hypertension is mostly unclear. As a result, our objective for the research aimed to investigate the present state as well as developments in the global usage of acupuncture on hypertension during the last 20 years using CiteSpace (5.8.R2). The Web of Science (WOS) database examined papers on acupuncture treatment of hypertension from 2002 to 2021. We examined the number of publications, cited journals, nations/regions, organizations, authors, cited authors, cited references, and keywords utilizing CiteSpace. The record of 296 documents was obtained between 2002 and 2021. The quantity and frequency of annual publications rose gradually. Regarding frequency and centrality of citations, Circulation and Clin Exp Hypertens (Clinical and Experimental Hypertension) scored top and second respectively. China had the most publications among countries/regions, as well as the five largest institutions were also in China. Cunzhi Liu was the most productive author, while P Li was the most referenced author. XF Zhao produced the first article inside the quantity of cited references classification. 'Electroacupuncture' had a significant frequency with centrality for the keywords, which suggested electroacupuncture is a popular treatment in this field. In the treatment of hypertension, electroacupuncture has a beneficial effect on reducing blood pressure. However, because of the many different applications of electroacupuncture frequencies in research, whether the electroacupuncture frequency is connected to the therapeutic impact should be given more significant consideration. The findings of this bibliometric analysis give an overview of the present state as well as developments of clinical studies on acupuncture for hypertensive patients during the last two decades, which could assist researchers in identifying hot subjects and exploring novel directions in further study within the field.

6.
Nat Commun ; 14(1): 540, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725882

RESUMO

How glasses relax at room temperature is still a great challenge for both experimental and simulation studies due to the extremely long relaxation time-scale. Here, by employing a modified molecular dynamics simulation technique, we extend the quantitative measurement of relaxation process of metallic glasses to room temperature. Both energy relaxation and dynamics, at low temperatures, follow a stretched exponential decay with a characteristic stretching exponent ß = 3/7, which is distinct from that of supercooled liquid. Such aging dynamics originates from the release of energy, an intrinsic nature of out-of-equilibrium system, and manifests itself as the elimination of defects through localized atomic strains. This finding is also supported by long-time stress-relaxation experiments of various metallic glasses, confirming its validity and universality. Here, we show that the distinct relaxation mechanism can be regarded as a direct indicator of glass transition from a dynamic perspective.

7.
Environ Sci Pollut Res Int ; 30(12): 32230-32245, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36735127

RESUMO

Ecological restoration projects are becoming a mainstream of research, and their studies are widely followed by scholars worldwide, yet there is no comprehensive review of this research. Nowadays, bibliometrics has attracted much attention from the scientific community, and its methodological approach allows quantitative and qualitative analysis of research performance in journals or subject areas. This paper provides a systematic and comprehensive description of the progress and hotspots of ecological restoration projects from a bibliometric perspective, based on 1173 articles in the Web of Science Core Collection (WOSCC) database. Research on ecological restoration projects has shown a positive growth trend since the twenty-first century. China and the USA are the most active countries in terms of the number of relevant articles published, and more than half of the top 10 active institutions are from China, but there is less collaboration between different countries/institutions. Research in ecological restoration projects is summarized into three main research areas: the main ecological damage problems, the impact of human beings on ecological damage, and the main methods of ecological restoration. Finally, some challenges and outlooks conducive to the rapid and balanced development of ecological restoration projects are presented, which provide valuable references and help for future researchers.


Assuntos
Bibliometria , Publicações , Humanos , Bases de Dados Factuais , China
8.
Macromol Biosci ; 23(3): e2200498, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36610012

RESUMO

Reactive oxygen species (ROS) in biological tissues are in a state of dynamic balance. However, many diseases such as cancer and inflammation, are accompanied by a long-term increase in ROS. This situation inspires researchers to use ROS-sensitive nanocarriers for a site-specific release of cargo in pathological areas. Polyamino acid materials with good biodegradability, biocompatibility, and regular secondary structure are widely used in the biomedical field. Herein, a new oxidation responsive PEGylated polyamino acid is synthesised for anticancer drug delivery by ring-opening polymerisation of N-carboxyanhydrides bearing thioether pendants. The obtained block copolymer mPEG-b-PMLG self-assembles into spherical nanoparticles (NPs) in water with diameter ≈68.3 nm. NMR measurement demonstrated that the hydrophobic thioether pendants in the NPs can be selectively oxidised to hydrophilic sulfoxide groups by H2 O2 , which will lead to the disassociation of NPs. In vitro drug release results indicated that the encapsulated Nile red is selectively released in the trigger of 10 mM H2 O2 in PBS. Finally, anticancer drug doxorubicin (DOX) is encapsulated to the NPs, and the obtained NPs/DOX exhibits an improved antitumor efficacy in 4T1 tumour-bearing mice and lower cardiotoxicity than free DOX. These results indicates that the mPEG-b-PMLG NPs are promising for anticancer drug delivery.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias , Camundongos , Animais , Sulfetos , Espécies Reativas de Oxigênio , Nanopartículas/química , Antineoplásicos/química , Polietilenoglicóis/química , Doxorrubicina/química , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Portadores de Fármacos/química , Liberação Controlada de Fármacos
9.
Front Bioeng Biotechnol ; 10: 1006388, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324902

RESUMO

Based on the Web of Science Core Collection (WOSCC) database, the academic works published in the past 30 years on biodegradable films for soil were analyzed. In order to ensure the rigor of this experiment, this paper is based on the mathematical double matrix model VOS Viewer software and CiteSpace software. This work shows that publications of biodegradable films for soil are increasing year by year; polymer science is the hottest subject in the field of biodegradable films for soil; China and the United States are the countries with the most significant number of publications in this field, has an important position; Washington State University is the most published institution. This study further identifies and reveals the essential characteristics, research strength, knowledge structure, main research fields, and research hotspots in the late stage of the field of biodegradable films for soil and introduces the Activity Index (AI) and the Attractive Index (AAI), thereby assessing trends and performance in different countries. The paper also further illustrates the importance of biodegradable films by presenting field trials using biodegradable films on different plants. The research in the field of biodegradable films for soil is divided into four categories: "The research field of degradation," "The effect of biodegradable film on soil," "Performance and mechanism of the biodegradable film," and "Effects of biodegradable film on crop growth and development.". The study can be seen as a microcosm of the development of biodegradable films for soils, which will help researchers quickly identify their general patterns. Readers can better understand the changes and development trends in this field in the past 30 years and provide references for future research.

10.
Front Chem ; 10: 915648, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873047

RESUMO

Since the 21st century, natural biopolymers have played an indispensable role in long-term global development strategies, and their research has shown a positive growth trend. However, these substantive scientific results are not conducive to our quick grasp of hotspots and insight into future directions and to understanding which local changes have occurred and which trend areas deserve more attention. Therefore, this study provides a new data-driven bibliometric analysis strategy and framework for mining the core content of massive bibliographic data, based on mathematical models VOS Viewer and CiteSpace software, aiming to understand the research prospects and opportunities of natural biopolymers. The United States is reported to be the most important contributor to research in this field, with numerous publications and active institutions; polymer science is the most popular subject category, but the further emphasis should be placed on interdisciplinary teamwork; mainstream research in this field is divided into five clusters of knowledge structures; since the explosion in the number of articles in 2018, researchers are mainly engaged in three fields: "medical field," "biochemistry field," and "food science fields." Through an in-depth analysis of natural biopolymer research, this article provides a better understanding of trends emerging in the field over the past 22 years and can also serve as a reference for future research.

11.
Zhongguo Gu Shang ; 35(3): 258-64, 2022 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-35322617

RESUMO

OBJECTIVE: According to 73 patients with middle clavicle fracture treated conservatively, a new classification of middle clavicle fracture was proposed, and the clinical effect of plastic splint in the treatment of middle clavicle fracture was observed. METHODS: Total 73 patients with middle clavicle fracture treated with plastic splint from September 2018 to August 2020 were analyzed retrospectively. All the patients were divided into 4 types according to the degree of fracture displacement. There were 16 cases of typeⅠ, including 7 males and 9 females, ranging in age from 18 to 37 years old, with a mean of (28.6±7.8) years old;12 cases of mild disease, 3 cases of moderate disease and 1 case of severe disease. There were 16 cases of type Ⅱ, including 6 males and 10 females, ranging in age from 25 to 49 years old, with a mean of (37.3±9.4) years old;5 cases of mild disease, 8 cases of moderate disease and 3 cases of severe disease. There were 7 cases of type Ⅲ, including 4 males and 3 females, ranging in age from 33 to 57 years old;2 cases of mild disease, 3 cases of moderate disease and 2 cases of severe disease. There were 34 cases of type Ⅳ, including 16 males and 18 females, ranging in age from 48 to 82 years old, with a mean of(66.4±14.9) years old;7 cases of mild disease, 17 cases of moderate disease and 10 cases of severe disease. All patients received plastic splint external fixation for 4 weeks. Visual analgue scale (VAS) and Constant-Murley shoulder scores before treatment and 1, 3 and 9 months after treatment were observed and recorded to evaluate the change of pain degree and shoulder function recovery before and after treatment. The patients' satisfaction with the appearance after treatment was recorded at the latest follow-up. The X-ray findings at the latest follow-up were used to judge whether the patient had fracture nonunion. And according to the fracture healing time and imaging findings, the excellent and good rate of clinical curative effect in patients with different types was obtained. RESULTS: All patients were followed up, and the duration ranged from 9 to 11 months, with a mean of (9.8±0.7) months. The VAS scores of typeⅠ, typeⅡand type Ⅳ before treatment were 2.88±0.83, 3.67±0.80 and 6.92±1.71 respectively, which were decreased to 0.54±0.19, 0.77±0.25 and 1.18±0.17 respectively after 9 months of treatment. The Constant-Murley shoulder scores of typeⅠ, typeⅡand type Ⅳ were 65.81±2.09, 63.50±2.22 and 47.93±2.91 respectively before treatment, and increased to 88.56±2.11, 85.12±2.23 and 71.25±2.16 respectively after 9 months of treatment. Five patients were not satisfied with the appearance after treatment;6 patients had no obvious continuous callus passing through after 9 months of treatment, which was fracture nonunion. CONCLUSION: The classification of middle clavicle fracture is more appropriate to the clinic, which has a certain clinical guiding significance for the selection of treatment methods and prognosis of middle clavicle fracture. Plastic splint is effective in the treatment of middle clavicle fracture without obvious displacement and overlapping displacement, and the incidence of complications is low. It can be popularized in clinic.


Assuntos
Clavícula , Contenções , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Clavícula/diagnóstico por imagem , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Plásticos , Estudos Retrospectivos , Adulto Jovem
12.
Nat Mater ; 21(2): 165-172, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34737454

RESUMO

Despite the importance of glass forming ability as a major alloy characteristic, it is poorly understood and its quantification has been experimentally laborious and computationally challenging. Here, we uncover that the glass forming ability of an alloy is represented in its amorphous structure far away from equilibrium, which can be exposed by conventional X-ray diffraction. Specifically, we fabricated roughly 5,700 alloys from 12 alloy systems and characterized the full-width at half-maximum, Δq, of the first diffraction peak in the X-ray diffraction pattern. A strong correlation between high glass forming ability and a large Δq was found. This correlation indicates that a large dispersion of structural units comprising the amorphous structure is the universal indicator for high metallic glass formation. When paired with combinatorial synthesis, the correlation enhances throughput by up to 100 times compared to today's state-of-the-art combinatorial methods and will facilitate the discovery of bulk metallic glasses.


Assuntos
Ligas , Vidro , Ligas/química , Vidro/química , Difração de Raios X
13.
Phys Chem Chem Phys ; 24(2): 861-874, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34908073

RESUMO

Src homology-2 domain-containing protein tyrosine phosphatase 1 (SHP1) is mainly restricted to hematopoietic and epithelial cells and widely accepted as a convergent node for oncogenic cell-signaling cascades. The development of efficient methods for rapidly tracing and inhibiting the SHP1 activity in complex biological systems is of considerable significance for advancing the integration of diagnosis and treatment of the related disease. With this aim, we designed and synthesized five 2-phenyl-1,3,4-thiadiazole derivatives (PT2, PT5, PT8, PT9 and PT10) here based on the reported SHP1 inhibitors (PT1, PT3, PT4, PT6 and PT7). The photophysical properties and inhibitory activities of these 2-phenyl-1,3,4-thiadiazole derivatives (PT1-PT10) against SHP1 were thoroughly studied from the theoretical simulation and experimental application aspects. The representative compound PT10 exhibited a larger quantum yield than the other molecules because of the smaller geometric relaxation and reorganization energy of the excited state, which was consistent with the results from the fluorescence experiments in organic solvents. In addition, PT10 showed a selective fluorescence response for SHP1 activity and low cytotoxicity in HeLa cells. Lastly, it indicated the potential application in two-photon cell fluorescence imaging in the future according to the calculated excellent two-photon absorption properties. In this contribution, firstly, we offered the fluorescent and activated molecule PT10 against SHP1, which achieved the integration of visualization and inhibitory activity of SHP1 preliminarily at the enzyme molecular level.


Assuntos
Teoria da Densidade Funcional , Inibidores Enzimáticos/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/antagonistas & inibidores , Tiadiazóis/farmacologia , Inibidores Enzimáticos/química , Células HeLa , Humanos , Estrutura Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Tiadiazóis/química
14.
ACS Appl Mater Interfaces ; 13(33): 40098-40105, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34375527

RESUMO

By decreasing the rate of physical vapor deposition, ZrCuAl metallic glasses with improved stability and mechanical performances can be formed, while the microscopic structural mechanisms remain unclear. Here, with scanning transmission electron microscopy and high-energy synchrotron X-ray diffraction, we found that the metallic glass deposited at a higher rate exhibits a heterogeneous structure with compositional fluctuations at a distance of a few nanometers, which gradually disappear on decreasing the deposition rate; eventually, a homogeneous structure is developed approaching ultrastability. This microscopic structural evolution suggests the existence of the following two dynamical processes during ultrastable metallic glass formation: a faster diffusion process driven by the kinetic energy of the depositing atoms, which results in nanoscale compositional fluctuations, and a slower collective relaxation process that eliminates the compositional and structural heterogeneity, equilibrates the deposited atoms, and strengthens the local atomic connectivity.

15.
Sci Bull (Beijing) ; 66(13): 1312-1318, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654153

RESUMO

Determination and conceptualization of atomic structures of metallic glasses or amorphous alloys remain a grand challenge. Structural models proposed for bulk metallic glasses are still controversial owing to experimental difficulties in directly imaging the atom positions in three-dimensional structures. With the advanced atomic-resolution imaging, here we directly observed the atomic arrangements in atomically thin metallic glassy membranes obtained by vapor deposition. The atomic packing in the amorphous membrane is shown to have a fractal characteristic, with the fractal dimension depending on the atomic density. Locally, the atomic configuration for the metallic glass membrane is composed of many types of polygons with the bonding angles concentrated on 45°-55°. The fractal atomic structure is consistent with the analysis by the percolation theory, and may account for the enhanced relaxation dynamics and the easiness of glass transition as reported for the thin metallic glassy films or glassy surface.

16.
Biomed Mater Eng ; 29(4): 485-497, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30282345

RESUMO

BACKGROUND: Lumbar spinal fusion in the interbody space is augmented with interbody fusion cages to provide structural support while arthrodesis occurs. Subsidence is a serious complication of interbody fusion. However, the biomechanical influence of anterior longitudinal ligament (ALL) and pedicle screws on subsidence has not been fully understood. OBJECTIVE: To investigate biomechanical effects of the hyperlordotic cages in different surgical conditions using finite element analysis. METHODS: Four surgical finite element (FE) models were constructed by inserting 15 degree lordosis cage at the L3-L4 disc space. The four surgical conditions were ALL intact (M1), ALL resected (M2), ALL intact and bilateral pedicle screws (M3), and ALL resected and bilateral pedicle screws (M4). Follow loads were applied at the L2 vertebral body while the inferior surface of L5 was fixed. FEA was implemented to simulate the four motion modes and biomechanical properties of four fusion scenarios with hyperlordotic interbody cage were compared. RESULTS: The range of motion (ROM) and facet joint force (FJF) at L3-L4 decreased significantly after fusion during all the motion modes. The cage stress and endplate stress at L3-L4 increased significantly after fusion during all the motion modes. The cage stress and endplate stress at L3-L4 for M3 and M4 were smaller than that for M1 and M2 during all the motion modes. The FJF at L3-L4 for M3 and M4 were smaller than that for M1 and M2 during extension, bending, and rotation. CONCLUSIONS: ALL has little effect on the biomechanics after lumbar fusion with hyperlordotic interbody cage. The bilateral pedicle screws significantly decreased the stress in cage, stress in endplate at L3-L4, and lowered facet contact force except for flexion mode. The implication is that the supplemental bilateral pedicle screws are recommended whether or not the ALL is resected.


Assuntos
Análise de Elementos Finitos , Parafusos Pediculares , Medula Espinal/cirurgia , Fusão Vertebral/métodos , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Lordose/terapia , Vértebras Lombares/cirurgia , Modelos Anatômicos
17.
World Neurosurg ; 114: e1120-e1129, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29609081

RESUMO

BACKGROUND: Lateral lumbar interbody fusion using cage supplemented with fixation has been used widely in the treatment of lumbar disease. A combined fixation (CF) of lateral plate and spinous process plate may provide multiplanar stability similar to that of bilateral pedicle screws (BPS) and may reduce morbidity. The biomechanical influence of the CF on cage subsidence and facet joint stress has not been well described. The aim of this study was to compare biomechanics of various fixation options and to verify biomechanical effects of the CF. METHODS: The surgical finite element models with various fixation options were constructed based on computed tomography images. The lateral plate and posterior spinous process plate were applied (CF). The 6 motion modes were simulated. Range of motion (ROM), cage stress, endplate stress, and facet joint stress were compared. RESULTS: For the CF model, ROM, cage stress, and endplate stress were the minimum in almost all motion modes. Compared with BPS, the CF reduced ROM, cage stress, and endplate stress in all motion modes. The ROM was reduced by more than 10% in all motion modes except for flexion; cage stress and endplate stress were reduced more than 10% in all motion modes except for rotation-left. After interbody fusion, facet joint stress was reduced substantially compared with the intact conditions in all motion modes except for flexion. CONCLUSIONS: The combined plate fixation may offer an alternative to BPS fixation in lateral lumbar interbody fusion.


Assuntos
Análise de Elementos Finitos/normas , Fixadores Internos/normas , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/normas , Adulto , Fenômenos Biomecânicos/fisiologia , Placas Ósseas/normas , Feminino , Humanos , Imageamento Tridimensional/métodos , Vértebras Lombares/fisiologia , Parafusos Pediculares/normas , Amplitude de Movimento Articular/fisiologia , Fusão Vertebral/métodos
18.
Comput Methods Biomech Biomed Engin ; 21(3): 247-254, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29513028

RESUMO

Inappropriate lordotic angle of lumbar fusion cage could be associated with cage damage or subsidence. The biomechanical influence of cage lordotic angle on lumbar spine has not been fully investigated. Four surgical finite element models were constructed by inserting cages with various lordotic angles at L3-L4 disc space. The four motion modes were simulated. The range of motion (ROM) decreased with increased lordotic angle of cage in flexion, extension, and rotation, whereas it was not substantially changed in bending. The maximum stress in cage decreased with increased lordotic angle of cage in all motion modes. The maximum stress in endplate at surgical level increased with increased lordotic angle of cage in flexion and rotation, whereas it was not substantially changed in extension and bending. The facet joint force (FJF) was much smaller than that for the intact conditions in extension, bending, and rotation, while it was not substantially changed in flexion. In conclusion, the ROM, stresses in the cage and endplate at surgical level are sensitive to the lordotic angle of cage. The increased cage lordotic angle may provide better stability and reduce the risk of cage damage, whereas it may increase the risk of subsidence in flexion and rotation.


Assuntos
Análise de Elementos Finitos , Lordose/fisiopatologia , Lordose/cirurgia , Vértebras Lombares/fisiopatologia , Vértebras Lombares/cirurgia , Fusão Vertebral , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Disco Intervertebral/patologia , Disco Intervertebral/fisiopatologia , Modelos Anatômicos , Pressão , Amplitude de Movimento Articular , Reprodutibilidade dos Testes , Rotação , Estresse Mecânico
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 27(4): 414-6, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-20677148

RESUMO

OBJECTIVE: To study a Chinese pedigree with Hailey-Hailey disease (HHD) and identify the ATP2C1 gene mutation in this family. METHODS: All exons of the ATP2C1 gene were analyzed with polymerase chain reaction and DNA sequencing in all patients of this family and 80 unrelated population-matched controls. RESULTS: We identified a nonsense mutation 163C to T, resulting in a premature termination codon in ATP2C1 gene. The mutation was not found in normal individuals of the family and controls. CONCLUSION: The mutation can affect the result of transcription and translation of ATP2C1 gene, and it is firstly reported in the Chinese pedigree with HHD.


Assuntos
Povo Asiático/genética , ATPases Transportadoras de Cálcio/genética , Pênfigo Familiar Benigno/genética , Análise Mutacional de DNA , Humanos , Linhagem
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