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1.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 38(4): 498-504, 2024 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-38632073

RESUMEN

Objective: To review the concept and methods of femoral bone tunnel positioning in anterior cruciate ligament (ACL) reconstruction, in order to provide a reference for clinical treatment. Methods: The relevant literature on the concept and methods of femoral bone tunnel positioning in ACL reconstruction in domestic and international research was extensively reviewed. Results: The position of the femoral bone tunnel is a key factor in determining the prognosis of ACL reconstruction. The concept of femoral bone tunnel positioning in ACL reconstruction has experienced isometric reconstruction, anatomical reconstruction, Ribbon-like theory, I.D.E.A.L. theory, and nearly isometric reconstruction theory. The femoral bone tunnel positioning technique is also changing with the in-depth study of the anatomy and biomechanics of the ACL, and each bone tunnel positioning technique has its own advantages and disadvantages. Over-The-Top technique is now mainly used for ACL revision; the clock-face positioning method is basically no longer applicable due to the large error, poor stability, and low retrievability; the bone landmarks positioning method (the lateral condyle of the femur's Resident's ridge and bifurcation ridge, and the the apex of the deep cartilage), which is now mostly used clinically due to the more constant anatomical landmarks. The quadrant method under X-ray fluoroscopy is more cumbersome to implement intraoperatively, so it is mainly used for academic research; computer navigation-assisted positioning has gradually become popular in recent years, which is highly accurate, avoids the influence of human factors on the positioning of the bone tunnel, and has a very good prospect of application; three-dimensional printing-assisted positioning technology, which is accurate in positioning, with a high degree of reproducibility and a short learning curve. Conclusion: The concept of femoral bone tunnel positioning for ACL reconstruction has undergone several evolutions, reflecting the deepening of the understanding of ACL and the improvement of the clinical results of reconstruction. The precision, personalization, and intelligence of positioning techniques are the focus of current and future development.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Humanos , Tibia/cirugía , Reproducibilidad de los Resultados , Fémur/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos , Fenómenos Biomecánicos , Lesiones del Ligamento Cruzado Anterior/cirugía , Articulación de la Rodilla/cirugía
2.
J Orthop Surg Res ; 19(1): 189, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500214

RESUMEN

PURPOSE: The aim of this study is to find a new method for femoral side preservation positioning in anterior cruciate ligament (ACL) reconstruction and test the accuracy and precision of this method. METHOD: Fifty patients with isolated ACL rupture (42 males and 8 females) who underwent single-bundle ACL reconstruction in our hospital between July 2022 and July 2023 were included. The lowest point of the cartilage margin of the lateral wall of the intercontinental fossa and the tibial plateau plumb line at 120° of knee flexion were used as the anatomical landmarks for positioning of the femoral tunnel for ACL reconstruction surgery. Femoral side remnant preservation was performed in all cases. Three-dimensional CT was performed 3 days postoperatively to collect the data, which were analyzed using Mimics 21.0 software. We measured the posterior cortical distance of the femoral condyle at 90° of knee flexion and the vertical distance from the center of the bone tunnel to the cortical extension line behind the femur. All femoral tunnel positions were marked on a 4 × 4 grid and visualized using the quadrant method. RESULTS: Using the new positioning method in 50 knees, the average distance of x was 25.26 ± 2.76% of t and the average distance of y was 23.69 ± 6.19% of h. This is close to the results of previous studies, where x was 24.2 ± 4.0% of t and the average distance of y was 21.6 ± 5.2% of h. Most femoral tunnel positions were located in the same area. The D values were distributed as follows: 60% in the range of 0 to 2 mm, 24% in the range of 2 to 4 mm, and 16% more than 4 mm. The E values were distributed as follows: 80% in the range of 0 to 4 mm and 20% more than 4 mm. CONCLUSION: In arthroscopic ACL reconstruction, the knee was flexed at 120° and the lowest point of the cartilage edge of the lateral wall of the intercondylar fossa and the tibial plateau plumb line were used as anatomical landmarks for the positioning of the femoral bone tunnel, which resulted in more accurate femoral bone tunnel positioning, better reproducibility, and better preservation of the femoral stump compared to traditional positioning methods.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Masculino , Femenino , Humanos , Reproducibilidad de los Resultados , Articulación de la Rodilla/cirugía , Fémur/diagnóstico por imagen , Fémur/cirugía , Tibia/cirugía , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/métodos
3.
Phys Chem Chem Phys ; 25(42): 28807-28813, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850498

RESUMEN

Hydrogen energy is very important as a new clean energy source to combat the growing environmental problems. In this regard, novel photocatalyst materials for water splitting have a wide range of applications. Using first principles calculations, we theoretically studied three orthorhombic group-IVB nitride halide monolayers, Hf2N2Br2, Janus HfZrN2Br2 and Janus Hf2N2ClBr. The energy, dynamic and thermal stabilities are demonstrated for all three monolayers. Using the HSE hybrid functional, the calculations reveal that they are direct band gap semiconductors with suitable band edge positions, good optical absorptions, and anisotropic carrier mobilities, which makes them promising for water splitting applications. Importantly, the photogenerated carriers provide enough driving force to trigger the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) within wide pH ranges, and then overall water splitting can be achieved spontaneously. We conclude that orthorhombic group-IVB nitride halide monolayers have potential applications in photocatalytic nanodevices.

5.
Pharm Biol ; 61(1): 1000-1012, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37410551

RESUMEN

CONTEXT: Hyperoside (Hyp), one of the active flavones from Rhododendron (Ericaceae), has beneficial effects against cerebrovascular disease. However, the effect of Hyp on vasodilatation has not been elucidated. OBJECTIVE: To explore the effect of Hyp on vasodilatation in the cerebral basilar artery (CBA) of Sprague-Dawley (SD) rats suffering with ischaemic-reperfusion (IR) injury. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into sham, model, Hyp, Hyp + channel blocker and channel blocker groups. Hyp (50 mg/kg, IC50 = 18.3 µg/mL) and channel blocker were administered via tail vein injection 30 min before ischaemic, followed by 20 min of ischaemic and 2 h of reperfusion. The vasodilation, hyperpolarization, ELISA assay, haematoxylin-eosin (HE), Nissl staining and channel-associated proteins and qPCR were analysed. Rat CBA smooth muscle cells were isolated to detect the Ca2+ concentration and endothelial cells were isolated to detect apoptosis rate. RESULTS: Hyp treatment significantly ameliorated the brain damage induced by IR and evoked endothelium-dependent vasodilation rate (47.93 ± 3.09% vs. 2.99 ± 1.53%) and hyperpolarization (-8.15 ± 1.87 mV vs. -0.55 ± 0.42 mV) by increasing the expression of IP3R, PKC, transient receptor potential vanilloid channel 4 (TRPV4), IKCa and SKCa in the CBA. Moreover, Hyp administration significantly reduced the concentration of Ca2+ (49.08 ± 7.74% vs. 83.52 ± 6.93%) and apoptosis rate (11.27 ± 1.89% vs. 23.44 ± 2.19%) in CBA. Furthermore, these beneficial effects of Hyp were blocked by channel blocker. DISCUSSION AND CONCLUSIONS: Although Hyp showed protective effect in ischaemic stroke, more clinical trial certification is needed due to the difference between animals and humans.


Asunto(s)
Antineoplásicos , Isquemia Encefálica , Daño por Reperfusión , Accidente Cerebrovascular , Humanos , Ratas , Animales , Ratas Sprague-Dawley , Canales Catiónicos TRPV/metabolismo , Células Endoteliales , Isquemia Encefálica/tratamiento farmacológico , Accidente Cerebrovascular/metabolismo , Vasodilatación , Antineoplásicos/farmacología , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Daño por Reperfusión/metabolismo
6.
Int J Clin Oncol ; 28(11): 1475-1485, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37470948

RESUMEN

OBJECTIVE: Dysregulated circular RNAs (circRNAs) have been verified to function in the development of gastric cancer (GC). The current study was designed to investigate the role of circ_0000419 in GC progression, and the potential mechanistic pathway. METHODS: Relative expression of circ_0000419, microRNA-300 (miR-300) and Repulsive Guidance Molecule B (RGMB) was analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay. Cell metastasis, including migration and invasion, was assessed by wound healing and Transwell assays. Glucose consumption and lactate production were examined using kits. The association between miR-300 and circ_0000419 or RGMB was validated by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assays. Role of circ_0000419 in vivo was determined by xenograft experiment. RESULTS: Circ_0000419 and RGMB were downregulated, while miR-300 was upregulated in GC tissues and cells. Gain of circ_0000419 inhibited migration, invasion and glycolysis in GC cells, which was attenuated by introduction of miR-300 or silencing of RGMB. Circ_0000419 sponged miR-300, and RGMB was direct target of miR-300. Circ_0000419 overexpression could block GC tumor growth in vivo. CONCLUSION: Circ_0000419 inhibited GC cell migration, invasion and glycolysis through regulation of miR-300/RGMB axis, at least in part, affording a molecular target for GC treatment.


Asunto(s)
MicroARNs , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Movimiento Celular/genética , Glucólisis/genética , Ácido Láctico , MicroARNs/genética , Proliferación Celular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/genética
7.
Zhongguo Zhong Yao Za Zhi ; 48(11): 3046-3054, 2023 Jun.
Artículo en Chino | MEDLINE | ID: mdl-37381963

RESUMEN

The aim of this study is to explore the mechanism of ligustilide, the main active constituent of essential oils of traditional Chinese medicine Angelicae Sinensis Radix, on alleviating oxygen-glucose deprivation/reperfusion(OGD/R) injury in PC12 cells from the perspective of ferroptosis. OGD/R was induced in vitro, and 12 h after ligustilide addition during reperfusion, cell viability was detected by cell counting kit-8(CCK-8) assay. DCFH-DA staining was used to detect the level of intracellular reactive oxygen species(ROS). Western blot was employed to detect the expression of ferroptosis-related proteins, glutathione peroxidase 4(GPX4), transferrin receptor 1(TFR1), and solute carrier family 7 member 11(SLC7A11), and ferritinophagy-related proteins, nuclear receptor coactivator 4(NCOA4), ferritin heavy chain 1(FTH1), and microtubule-associated protein 1 light chain 3(LC3). The fluorescence intensity of LC3 protein was analyzed by immunofluorescence staining. The content of glutathione(GSH), malondialdehyde(MDA), and Fe was detected by chemiluminescent immunoassay. The effect of ligustilide on ferroptosis was observed by overexpression of NCOA4 gene. The results showed that ligustilide increased the viability of PC12 cells damaged by OGD/R, inhibited the release of ROS, reduced the content of Fe and MDA and the expression of TFR1, NCOA4, and LC3, and improved the content of GSH and the expression of GPX4, SLC7A11, and FTH1 compared with OGD/R group. After overexpression of the key protein NCOA4 in ferritinophagy, the inhibitory effect of ligustilide on ferroptosis was partially reversed, indicating that ligustilide may alleviate OGD/R injury of PC12 cells by blocking ferritinophagy and then inhibiting ferroptosis. The mechanism by which ligustilide reduced OGD/R injury in PC12 cells is that it suppressed the ferroptosis involved in ferritinophagy.


Asunto(s)
Ferroptosis , Animales , Ratas , Células PC12 , Ferroptosis/genética , Especies Reactivas de Oxígeno , Factores de Transcripción , Glutatión
9.
J Chem Phys ; 158(20)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37212410

RESUMEN

The complex phase diagram and bonding nature of the TiAl system make it difficult to accurately describe its various properties and phases by traditional atomistic force fields. Here, we develop a machine learning interatomic potential with a deep neural network method for the TiAlNb ternary alloy based on a dataset built by first-principles calculations. The training set includes bulk elementary metals and intermetallic structures with slab and amorphous configurations. This potential is validated by comparing bulk properties-including lattice constant and elastic constants, surface energies, vacancy formation energies, and stacking fault energies-with their respective density functional theory values. Moreover, our potential could accurately predict the average formation energy and stacking fault energy of γ-TiAl doped with Nb. The tensile properties of γ-TiAl are simulated by our potential and verified by experiments. These results support the applicability of our potential under more practical conditions.

10.
Zhongguo Gu Shang ; 36(4): 393-8, 2023 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-37087632

RESUMEN

Pentaxin 3 (PTX3), as a multifunctional glycoprotein, plays an important role in regulating inflammatory response, promoting tissue repair, inducing ectopic calcification and maintaining bone homeostasis. The effect of PTX3 on bone mineral density (BMD) may be affected by many factors. In PTX3 knockout mice and osteoporosis (OP) patients, the deletion of PTX3 will lead to decrease of BMD. In Korean community "Dong-gu study", it was found that plasma PTX3 was negatively correlated with BMD of femoral neck in male elderly patients. In terms of bone related cells, PTX3 plays an important role in maintaining the phenotype and function of osteoblasts (OB) in OP state;for osteoclast (OC), PTX3 in inflammatory state could stimulate nuclear factor κ receptor activator of nuclear factor-κB ligand (RANKL) production and its combination with TNF-stimulated gene 6(TSG-6) could improve activity of osteoclasts and promote bone resorption;for mesenchymal stem cells (MSCs), PTX3 could promote osteogenic differentiation of MSCs through PI3K/Akt signaling pathway. In recent years, the role of PTX3 as a new bone metabolism regulator in OP and fracture healing has been gradually concerned by scholars. In OP patients, PTX3 regulates bone mass mainly by promoting bone regeneration. In the process of fracture healing, PTX3 promotes fracture healing by coordinating bone regeneration and bone resorption to maintain bone homeostasis. In view of the above biological characteristics, PTX3 is expected to become a new target for the diagnosis and treatment of OP and other age-related bone diseases and fracture healing.


Asunto(s)
Resorción Ósea , Curación de Fractura , Osteoporosis , Animales , Masculino , Ratones , Resorción Ósea/metabolismo , Diferenciación Celular , Curación de Fractura/genética , Osteoblastos , Osteoclastos , Osteogénesis , Osteoporosis/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/farmacología
11.
Histol Histopathol ; 38(12): 1443-1451, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36856372

RESUMEN

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. A lack of effective targeted therapies against CRC makes the treatment challenging. Here, we report a circular RNA (circRNA), has_circ_0071803, functioning as an oncogene in CRC. Circ_0071803 was upregulated in CRC tissues and cell lines, and its expression levels were inversely correlated with the prognosis and survival rate of patients with CRC. Circ_0071803 knockdown suppressed cell proliferation, migration, and invasion in CRC. Moreover, we found that circ_0071803 sponged miR-330-5p, thereby upregulating mitogen-activated protein kinase 1 (MAPK1) in CRC cells. The suppression of cell activities by circ_0071803 knockdown were rescued by miR-330-5p inhibition or MAPK1 overexpression. Collectively, our findings elucidate that circ_0071803 promotes CRC progression by regulating the miR-330-5p/MAPK1 pathway, providing potential therapeutic targets for designing effective targeted treatments.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , Humanos , Sistema de Señalización de MAP Quinasas , Transducción de Señal , Oncogenes , Proliferación Celular/genética , Neoplasias Colorrectales/genética , MicroARNs/genética , Línea Celular Tumoral
12.
Zhongguo Zhong Yao Za Zhi ; 48(2): 455-464, 2023 Jan.
Artículo en Chino | MEDLINE | ID: mdl-36725235

RESUMEN

This study explores the effect of total flavonoids of Rhododendra simsii(TFR) on middle cerebral artery occlusion(MCAO)-induced cerebral injury in rats and oxygen-glucose deprivation/reoxygenation(OGD/R) injury in PC12 cells and the underlying mechanism. The MCAO method was used to induce focal ischemic cerebral injury in rats. Male SD rats were randomized into sham group, model group, and TFR group. After MCAO, TFR(60 mg·kg~(-1)) was administered for 3 days. The content of tumor necrosis factor-α(TNF-α), interleukin-1(IL-1), and interleukin-6(IL-6) in serum was detected by enzyme-linked immunosorbent assay(ELISA). The pathological changes of brain tissue and cerebral infarction were observed based on hematoxylin and eosin(HE) staining and 2,3,5-triphenyltetrazolium chloride(TTC) staining. RT-qPCR and Western blot were used to detect the mRNA and protein levels of calcium release-activated calcium channel modulator 1(ORAI1), stromal interaction molecule 1(STIM1), stromal intera-ction molecule 2(STIM2), protein kinase B(PKB), and cysteinyl aspartate specific proteinase 3(caspase-3) in brain tissues. The OGD/R method was employed to induce injury in PC12 cells. Cells were randomized into the normal group, model group, gene silencing group, TFR(30 µg·mL~(-1)) group, and TFR(30 µg·mL~(-1))+gene overexpression plasmid group. Intracellular Ca~(2+) concentration and apoptosis rate of PC12 cells were measured by laser scanning confocal microscopy and flow cytometry. The effect of STIM-ORAI-regulated store-operated calcium entry(SOCE) pathway on TFR was explored based on gene silencing and gene overexpression techniques. The results showed that TFR significantly alleviated the histopathological damage of brains in MCAO rats after 3 days of admini-stration, reduced the contents of TNF-α, IL-1, and IL-6 in the serum, down-regulated the expression of ORAI1, STIM1, STIM2, and caspase-3 genes, and up-regulated the expression of PKB gene in brain tissues of MCAO rats. TFR significantly decreased OGD/R induced Ca~(2+) overload and apoptosis in PC12 cells. However, it induced TFR-like effect by ORAI1, STIM1 and STIM2 genes silencing. However, overexpression of these genes significantly blocked the effect of TFR in reducing Ca~(2+) overload and apoptosis in PC12 cells. In summary, in the early stage of focal cerebral ischemia-reperfusion injury and OGD/R-induced injury in PC12 cells TFR attenuates ischemic brain injury by inhibiting the STIM-ORAI-regulated SOCE pathway and reducing Ca~(2+) overload and inflammatory factor expression, and apoptosis.


Asunto(s)
Isquemia Encefálica , Flavonoides , Daño por Reperfusión , Animales , Masculino , Ratas , Apoptosis , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Caspasa 3 , Interleucina-1 , Interleucina-6 , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismo , Factor de Necrosis Tumoral alfa/genética , Flavonoides/farmacología , Rhododendron/química
13.
J Phys Condens Matter ; 35(14)2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36689775

RESUMEN

Prediction and synthesis of two-dimensional high transition temperature (TC) superconductors is an area of extensive research. Based on calculations of the electronic structures and lattice dynamics, we predict that graphene-like layered monolayer LiC12is aπ-electrons mediated Bardeen-Cooper-Schrieffer-type superconductor. Monolayer LiC12is theoretically stable and expected to be synthesized experimentally. From the band structures and the phonon dispersion spectrum, it is found that the saddle point ofπ-bonding bands induces large density of states at the Fermi energy level. There is strongly coupled between the vibration mode in the in-plane direction of the lithium atoms and theπ-electrons of carbon atoms, which induces the high-TCsuperconductivity in LiC12. TheTCcan reach to 41 K under an applied 10% biaxial tensile strain based on the anisotropic Eliashberg equation. Our results show that monolayer LiC12is a good candidate asπ-electrons mediated electron-phonon coupling high-TCsuperconductor.

14.
Microbiol Spectr ; 11(1): e0350922, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36598279

RESUMEN

Bacterial defense barriers, such as DNA methylation-associated restriction-modification (R-M) and the CRISPR-Cas system, play an important role in bacterial antimicrobial resistance (AMR). Recently, a novel R-M system based on DNA phosphorothioate (PT) modification has been shown to be widespread in the kingdom of Bacteria as well as Archaea. However, the potential role of the PT R-M system in bacterial AMR remains unclear. In this study, we explored the role of PT R-Ms in AMR with a series of common clinical pathogenic bacteria. By analyzing the distribution of AMR genes related to mobile genetic elements (MGEs), it was shown that the presence of PT R-M effectively reduced the distribution of horizontal gene transfer (HGT)-derived AMR genes in the genome, even in the bacteria that did not tend to acquire AMR genes by HGT. In addition, unique gene variation analysis based on pangenome analysis and MGE prediction revealed that the presence of PT R-M could suppress HGT frequency. Thus, this is the first report showing that the PT R-M system has the potential to repress HGT-derived AMR gene acquisition by reducing the HGT frequency. IMPORTANCE In this study, we demonstrated the effect of DNA PT modification-based R-M systems on horizontal gene transfer of AMR genes in pathogenic bacteria. We show that there is no apparent association between the genetic background of the strains harboring PT R-Ms and the number of AMR genes or the kinds of gene families. The strains equipped with PT R-M harbor fewer plasmid-derived, prophage-derived, or integrating mobile genetic element (iMGE)-related AMR genes and have a lower HGT frequency, but the degree of inhibition varies among different bacteria. In addition, compared with Salmonella enterica and Escherichia coli, Klebsiella pneumoniae prefers to acquire MGE-derived AMR genes, and there is no coevolution between PT R-M clusters and bacterial core genes.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Bacterias/genética , Enzimas de Restricción-Modificación del ADN/genética , ADN , Transferencia de Gen Horizontal
15.
Nanotechnology ; 34(9)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36379048

RESUMEN

Tilted fiber Bragg grating (TFBG) is a widespread approach for developing refractive index (RI) sensors. The unique optoelectronic properties exhibited by MXene are expected to enhance the performance of TFBG-SPR sensors. In this study, a Ta2C coating appropriate for sensing was obtained by optimizing the photo-deposition time, which addressed the challenge of preparing large areas of MXene. The uniform coating of the few-layer Ta2C increases the wavelength sensitivity and FOM of the sensor to 229.5 nm/RIU and 2228.15 respectively. This significant enhancement was attributed to an ordered MXene phase of the grown Ta2C. The energy band theory verified the metallic nature of the Ta2C and the amplification effect on the RI response. Finite element analysis demonstrated that the stronger absorption band of Ta2C facilitated the generation of surface plasmon polariton. Based on the above benefits, the sensor detected melamine in milk with a detection limit of 7.9 × 10-9M. The TFBG/Au/Ta2C sensor is a promising approach for biochemical analysis and trace detection.

16.
J Phys Chem B ; 126(41): 8188-8201, 2022 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-36222098

RESUMEN

The catalytic cycle of the enzyme adenylate kinase involves large conformational motions between open and closed states. A previous single-molecule experiment showed that substrate binding tends to accelerate both the opening and the closing rates and that a single turnover event often involves multiple rounds of conformational switching. In this work, we showed that the repeated conformational transitions of adenylate kinase are essential for the relaxation of incorrectly bound substrates into the catalytically competent conformation by combining all-atom and coarse-grained molecular simulations. In addition, free energy calculations based on all-atom and coarse-grained models demonstrated that the enzyme with incorrectly bound substrates has much a lower free energy barrier for domain opening compared to that with the correct substrate conformation, which may explain the the acceleration of the domain opening rate by substrate binding. The results of this work provide mechanistic understanding to previous experimental observations and shed light onto the interplay between conformational dynamics and enzyme catalysis.


Asunto(s)
Adenilato Quinasa , Simulación de Dinámica Molecular , Adenilato Quinasa/química , Conformación Proteica , Catálisis
17.
J Phys Chem Lett ; 13(44): 10297-10304, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36305806

RESUMEN

The valley-polarized quantum anomalous Hall effect (VP-QAHE) in topological materials, which usually is induced by applying external manipulations, has attracted intensive attention. Here, we predict the formation and regulation of the intrinsic VP-QAHE in ferromagnetic Janus monolayer Fe2SSe. Spontaneous valley polarization (VP) appears without external manipulations due to the Janus structure in monolayer Fe2SSe. The spontaneous VP in addition to the nonzero Chern number in Fe2SSe confirm the intrinsic VP-QAHE. Besides, the topologically protected chiral-spin-valley locking edge states can be regulated by reversing the magnetization. Topological phase transitions between metal, half-metal, topological insulator, and ferrovalley phases can be obtained by applying biaxial strains in Fe2SSe, and the nontrivial band gap reaches up to 441 meV. Also, the topological phase with the VP-QAHE is robust under certain conditions. Both the intrinsic VP-QAHE and controllable topological phase transitions can be achieved in Janus monolayer Fe2SSe, which provides an avenue for the applications of dissipationless valleytronic devices.

18.
Comput Math Methods Med ; 2022: 5048172, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36045948

RESUMEN

Objective: The aim of the present research is to analyze the impact of the bridge combined internal fixation system (BCFS) on efficacy, complications, and inflammatory reactions of periarticular fractures of the shoulder. Methods: A retrospective analysis was performed on 100 patients with periarticular fractures of the shoulder admitted between January 2016 and January 2020. Patients were assigned to the observation group (OG) and control group (CG) according to different treatment schemes, with 50 cases in each group. Patients in OG were intervened by BCFS, while those in CG were routinely given plate fixation. The treatment outcome, complications, and inflammatory reaction of the two groups were compared. Results: The results showed better treatment outcome, shoulder joint function recovery, and inflammatory reaction alleviation of OG compared with CG. Besides, statistically shorter fracture healing and hospitalization time as well as fewer complications were determined in OG. Conclusion: These results demonstrate that compared with the plate fixation system, BCFS can significantly improve the surgical efficacy and healing efficiency and alleviate the inflammatory response of patients, with a low complication rate, all of which contribute to faster recovery of periarticular fractures of the shoulder. Hence, BCFS is an ideal choice for periarticular fractures of the shoulder that deserves clinical promotion.


Asunto(s)
Fracturas Óseas , Fracturas del Hombro , Placas Óseas , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Curación de Fractura , Fracturas Óseas/cirugía , Humanos , Estudios Retrospectivos , Hombro , Fracturas del Hombro/cirugía , Resultado del Tratamiento
19.
Comput Intell Neurosci ; 2022: 5207553, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36105630

RESUMEN

Objective: The objective is to observe the changes in aberrations before and after surgery in patients with common horizontal strabismus and to analyze the possible reasons for the changes. Methods: Forty eyes of 40 cases with concomitant exotropia who underwent strabismus correction at the Ophthalmology Department of Nantong University Hospital from October 2020 to July 2021 were included in this study, all of whom underwent unilateral lateral rectus recession combined with a medial rectus resection in the same eye. Aberration parameters were measured 1 day before surgery and 1 week, 1 month, 3 months, and 6 months after surgery. Differences in the indicators at each time period were compared by analysis of variance (ANOVA) of repeated measures data for a single factor, and data were analyzed using SPSS 25.0 statistical application software. Results: 5 mm pupil diameter: the preoperative and postoperative RMS of total aberration showed statistically significant difference (P < 0.01). Postoperation test (Bonferroni method) and preoperative comparison at each period after surgery showed statistically significant differences between 6 months after surgery (P=0.002) and preoperative comparison. The preoperative and postoperative comparison of RMS in LOAs was statistically significant (P < 0.01); postoperative test (Bonferroni method) and preoperative comparison showed that there were statistically significant differences between 1 week (P=0.033) and 6 months (P=0.002) after operation. The difference of RMS of defocus before and after operation was statistically significant (P < 0.01); postoperation test (Bonferroni method) and preoperative comparison showed that there was statistically significant difference between 6 months after operation (P=0.007) and preoperative comparison. There was statistically significant difference in preoperative and postoperative RMS of HOAs (P=0.013). Postoperative test (Bonferroni method) and preoperative comparison showed that there was statistically significant difference 6 months after surgery (P=0.03). The RMS of secondary astigmatism showed a statistically significant difference before and after operation (P=0.001), and the postoperation test (Bonferroni method) showed a statistically significant difference 6 months after operation (P=0.002). In 5 mm pupil diameter, the preoperative and postoperative RMS of total aberration showed statistically significant difference (P < 0.01), postoperative test (Bonferroni method) was used to compare each period after surgery with that before surgery, and there were statistically significant differences between 1 week after surgery (P=0.034), 3 months after surgery (P=0.033), and 6 months after surgery (P=0.003). The preoperative and postoperative comparison of RMS in LOAs was statistically significant (P < 0.01), postoperative test (Bonferroni method) was used to compare each period after surgery with that before surgery, and there were statistically significant differences between 1 week after surgery (P=0.04), 3 months after surgery (P=0.034), and 6 months after surgery (P=0.004). The difference of RMS of defocus before and after surgery was statistically significant (P=0.002), and the comparison between postoperation test (Bonferroni method) and preoperation showed that the difference was statistically significant 6 months after surgery (P=0.027). The RMS of astigmatism showed statistically significant difference before and after operation (P=0.002), and the postoperation test (Bonferroni method) showed statistically significant difference between 6 months after operation (P=0.009) and before operation. Conclusion: We found that horizontal rectus surgery had a transient effect on LOAs and almost no effect on HOAs. Long-term follow-up is recommended after strabismus surgery to observe eye position and binocular visual function. Because of the high prevalence of strabismus in adolescents, long-term observation of the eye axis and aberration is recommended.


Asunto(s)
Astigmatismo , Exotropía , Adolescente , Astigmatismo/etiología , Astigmatismo/cirugía , Exotropía/complicaciones , Exotropía/cirugía , Humanos , Músculos Oculomotores/cirugía , Estudios Retrospectivos , Visión Binocular
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