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1.
Science ; 383(6684): 732-739, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38359129

RESUMO

Polygalacturonase-inhibiting proteins (PGIPs) interact with pathogen-derived polygalacturonases to inhibit their virulence-associated plant cell wall-degrading activity but stimulate immunity-inducing oligogalacturonide production. Here we show that interaction between Phaseolus vulgaris PGIP2 (PvPGIP2) and Fusarium phyllophilum polygalacturonase (FpPG) enhances substrate binding, resulting in inhibition of the enzyme activity of FpPG. This interaction promotes FpPG-catalyzed production of long-chain immunoactive oligogalacturonides, while diminishing immunosuppressive short oligogalacturonides. PvPGIP2 binding creates a substrate binding site on PvPGIP2-FpPG, forming a new polygalacturonase with boosted substrate binding activity and altered substrate preference. Structure-based engineering converts a putative PGIP that initially lacks FpPG-binding activity into an effective FpPG-interacting protein. These findings unveil a mechanism for plants to transform pathogen virulence activity into a defense trigger and provide proof of principle for engineering PGIPs with broader specificity.


Assuntos
Fusarium , Phaseolus , Imunidade Vegetal , Proteínas de Plantas , Poligalacturonase , Fatores de Virulência , Imunidade Inata , Proteínas de Plantas/metabolismo , Poligalacturonase/metabolismo , Fatores de Virulência/metabolismo , Fusarium/imunologia , Fusarium/patogenicidade , Phaseolus/imunologia , Phaseolus/microbiologia
2.
Int J Surg ; 109(9): 2672-2679, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37379168

RESUMO

BACKGROUND: Surgery is still the most important treatment method for thyroid cancer. The classic linea alba cervicalis approach caused obvious neck scarring. This study explored an alternative open operative approach with concealed incision for hemithyroidectomy, and demonstrated whether it was non-inferior to traditional approach in postoperative complications and operation efficiency. METHODS: Patients ( n =220) from November 2019 to November 2020 willing to undergo hemithyroidectomy because of differentiated thyroid cancer were randomly divided into the sternocleidomastoid intermuscular approach (SMIA) group ( n =110), and the linea alba cervicalis approach (LACA) group ( n =110). The incidence of postoperative complications within 3 months and operation efficiency indicator R0 resection rate were recorded as primary endpoint, while scar apperance was assessed as secondary endpoint. The data were statistically analyzed. RESULTS: The baseline data of these two groups were comparable, with no significant difference ( P >0.05). As primary endpoint, R0 resection rate was 100% in both groups. In the 1-month follow-up period, the SMIA group had a lower score for neck discomfort compared with that of the LACA group (1.01±0.1648 vs. 0.5657±0.0976, P =0.0217). The SMIA group's scar had better results from the observer scar assessment compared to that of the LACA group as secondary endpoint. Within the 3-month follow-up, the total complications were calculated, and it was demonstrated that SMIA was non-inferior to traditional LACA operation ( P of non-inferiority=0.0048). CONCLUSIONS: Compared with LACA group, surgery through the SMIA is safe, effective, and has non-inferior postoperative complications. SMIA can be considered an alternative approach to classic LACA in hemithyroidectomy.


Assuntos
Cicatriz , Neoplasias da Glândula Tireoide , Humanos , Cicatriz/etiologia , Cicatriz/prevenção & controle , Tireoidectomia/efeitos adversos , Tireoidectomia/métodos , Neoplasias da Glândula Tireoide/cirurgia , Esvaziamento Cervical/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/cirurgia
3.
Int Orthop ; 47(6): 1423-1431, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37042970

RESUMO

PURPOSE: Periprosthetic joint infection (PJI) is a serious hip and knee arthroplasty complication. Despite the increased incidence of primary joint replacements, there is no clear guideline for treating PJI in the Chinese mainland yet. We aim to measure the current situation and basis for surgical treatment methods of PJI in major orthopaedic hospitals in the Chinese mainland. METHODS: We conducted a national survey on PJI treatment in Mainland China. Forty-one top arthroplasty centers were included, with 82.9% (34/41) response rate. The data were analyzed using Microsoft Excel version 20.0 and described as numbers and percentages. RESULTS: For acute infections, prosthesis-preserving procedures (DAIR) are used in all centres. For hip and knee PJI, 20.5% (7/34) and 35% (12/34) of the centres used a one-stage exchange. If applied, this treatment will necessitate the previous patients' selection for a satisfactory outcome. All centres execute the two-stage exchange. Between phases, the majority of centres implant a cemented spacer. Revisions for infected hips included 21 (4.3%) cases of DAIR, 95 (19.9%) cases of single-stage exchange, 362 (75.2%) cases of two-stage exchange, and 2 (0.007%) cases of hip dissection. Revisions for infected knee comprised 88 (19.0%) cases of DAIR, 48 (10.3%) cases of single-stage exchange, 324 (69.8%) cases of two-stage exchange, and 5 (0.02%) cases of knee fusion. CONCLUSIONS: The centers do not have a uniform PJI standard. Most patients have two-stage revision with a cemented spacer in China. These concepts can help establish treatment guidelines.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Infecções Relacionadas à Prótese , Humanos , Antibacterianos/uso terapêutico , Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , População do Leste Asiático , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Artroplastia do Joelho/efeitos adversos , Artroplastia do Joelho/métodos
4.
Magn Reson Chem ; 60(8): 836-844, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35307870

RESUMO

For 3d1 (V4+ ) impurity in 30PbO-5Bi2 O3 -(65-x)SiO2 glass systems with different concentrations x of V2O5, the defect structures and gyromagnetic factors are theoretically investigated by using the perturbation formulas of g factors for a tetragonally compressed octahedral 3d1 group. The concentration dependences of d-d transition band and g factors are suitably explained from the Fourier type concentration functions of the cubic crystal field parameter Dq, covalency factor N and relative tetragonal compression ratio ρ. The above concentration dependences of these quantities are suitably illustrated by the modifications of the local crystal field strength and electron cloud distribution with increasing x. The concentration variations of the electrical conductivity and dielectric relaxation are further analyzed from the stability of the systems in view of two competitive factors (increasing network polymerization and bulk stability at low concentrations and decreasing former SiO2 and stability at high concentrations).


Assuntos
Vidro , Dióxido de Silício , Espectroscopia de Ressonância de Spin Eletrônica , Vidro/química
5.
Front Cell Dev Biol ; 9: 758339, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34805166

RESUMO

The tumor microenvironment heterogeneity of papillary thyroid cancer (PTC) is poorly characterized. The relationship between PTC and Hashimoto thyroiditis (HT) is also in doubt. Here, we used single-cell RNA sequencing to map the transcriptome landscape of PTC from eight PTC patients, of which three were concurrent with HT. Predicted copy number variation in epithelial cells and mesenchymal cells revealed the distinct molecular signatures of carcinoma cells. Carcinoma cells demonstrated intertumoral heterogeneity based on BRAF V600E mutation or lymph node metastasis, and some altered genes were identified to be correlated with disease-free survival in The Cancer Genome Atlas datasets. In addition, transcription factor regulons of follicular epithelial cells unveil the different transcription activation state in PTC patients with or without concurrent HT. The immune cells in tumors exhibited distinct transcriptional states, and the presence of tumor-infiltrating B lymphocytes was predominantly linked to concurrent HT origin. Trajectory analysis of B cells and plasma cells suggested their migration potential from HT adjacent tissues to tumor tissues. Furthermore, we revealed diverse ligand-receptor pairs between non-immune cells, infiltrating myeloid cells, and lymphocytes. Our results provided a single-cell landscape of human PTC. These data would deepen the understanding of PTC, as well as the immunological link between PTC and HT.

6.
Magn Reson Chem ; 59(4): 439-446, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33084084

RESUMO

The local structure, d-d transition band, and spin Hamiltonian parameters (SHPs) are theoretically studied for the V4+ probe in Na2 O-PbO-Bi2 O3 -SiO2 (NPBS) glass ceramics containing V2 O5 dopant with various concentration x (0 ≤ x ≤ 5 mol%) by using the perturbation formulas of the SHPs for tetragonally compressed octahedral 3d1 clusters. The first decreasing (or increasing) and then increasing (or decreasing) d-d transition band (= 10 Dq ) and hyperfine structure constants A// and A⊥ (or g factors g// and g⊥ ) with x can be suitably simulated with the similarly varying Fourier type concentration functions of cubic field parameter Dq , covalence factor N, core polarization constant κ, and reduction factor H (or relative tetragonal compression ratio ρ), with the minima (or maxima) at the middle concentration x = 3 mol%, respectively. The above concentration variations of SHPs and the related quantities may originate from the modifications of local crystal field strength, tetragonal compression, and electron cloud distribution near the impurity V4+ with x, corresponding to the highest [V4+ ]/[V5+ ] ratio at 3 mol%. Present studies would be helpful to explore novel sodium lead bismuth silicate glass ceramics by modifying the concentration of V2 O5 dopant.

8.
Sci Rep ; 9(1): 14739, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31611570

RESUMO

As a universal quantum character of quantum correlation, the freezing phenomenon is researched by geometry and quantum discord methods, respectively. In this paper, the properties of Rènyi discord is studied for two independent Dimer System coupled to two correlated Fermi-spin environments under the non-Markovian condition. We further demonstrate that the freezing behaviors still exist for Rènyi discord and study the effects of different parameters on this behaviors.

9.
Chin J Traumatol ; 16(5): 259-64, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24103819

RESUMO

OBJECTIVE: To evaluate the anatomy of femoral tunnels created by simulated transtibial technique in double-bundle anterior cruciate ligament (ACL) reconstruction. METHODS: Two tibial tunnels, anteromedial (AM) and posterolateral (PL), were drilled 45?and 55?to tibial plateau respectively. On the femoral side, the AM and PL tunnels were drilled through anteriomedial portal. After the four tunnels were established, the shaft of a reamer was introduced into the joint through tibial tunnel and reached against the lateral wall of intercondylar notch. The position that the reamer shaft can reach was marked and recorded. RESULTS: Neither femoral AM nor PL tunnel opening can be fully or partially reached by the reamer shaft through the tibial AM tunnel in all cases. The evaluation through the tibial PL tunnel showed that only in 8 of 50 cases (16%) the femoral AM tunnel opening and in 4 cases (8%) the PL opening can be fully reached. On the other hand, in 12 cases (24%) the femoral AM tunnel opening and in 10 cases (20%) the PL opening can be partially reached by the shafts through the tibial PL tunnel. CONCLUSION: The result strongly suggests that transtibial technique is not well competent for femoral tunnel drilling in anatomic double-bundle ACL reconstruction as we have hypothesized.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Fêmur/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/reabilitação , Tíbia
10.
Eur J Orthop Surg Traumatol ; 23(6): 731-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23412179

RESUMO

In anterior cruciate ligament (ACL) reconstruction, transtibial drilling of the femoral tunnel has been criticized for its vertical and less anatomical tunnel, which accompanied rotational instability of knee. Many authors recommend anteromedial (AM) portal drilling technique, which creates more oblique and anatomic femoral tunnel. However, recent researches show that oblique tunnel is related to risks of too short femoral tunnel, blowout of back wall, and posterolateral structures injury. Is oblique femoral tunnel really essential for anatomic reconstruction? We introduce a modified AM technique, which abandons the oblique tunnel and provides vertical femoral tunnel and oblique graft with anatomic starting point. The fundamental of the new technique is that oblique graft but not oblique tunnel is essential for rotational stability of knee. Thus, it avoids the risks and preserves anatomic reproduction of ACL.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior/métodos , Artroscopia/métodos , Fêmur/cirurgia , Articulação do Joelho/cirurgia , Tíbia/cirurgia , Ligamento Cruzado Anterior/cirurgia , Humanos , Resultado do Tratamento
11.
Nanoscale Res Lett ; 7(1): 562, 2012 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-23046910

RESUMO

A sample of the ß-Ga2O3/wurtzite GaN heterostructure has been grown by dry thermal oxidation of GaN on a sapphire substrate. X-ray diffraction measurements show that the ß-Ga2O3 layer was formed epitaxially on GaN. The valence band offset of the ß-Ga2O3/wurtzite GaN heterostructure is measured by X-ray photoelectron spectroscopy. It is demonstrated that the valence band of the ß-Ga2O3/GaN structure is 1.40 ± 0.08 eV.

12.
Orthopedics ; 34(7): 524-9, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21717971

RESUMO

Proximal soft tissue realignment is the main surgical intervention for recurrent patellar instability. In recent years, all-inside arthroscopic procedures or mini-open surgeries have replaced traditional surgeries, which have more associated morbidity and poor cosmetic results. This article describes a simple and all-inside arthroscopic technique for the operative treatment of recurrent patellar instability. Using 2 epidural needles in several steps and no accessory portals required, the medial patellar retinaculum is imbricated to the desired tension. The combination of lateral release and medial retinacular placation obviously improves the patellar tracking compared with preoperatively.


Assuntos
Artroscopia/métodos , Instabilidade Articular/cirurgia , Articulação do Joelho/cirurgia , Patela/cirurgia , Humanos , Instabilidade Articular/fisiopatologia , Articulação do Joelho/fisiopatologia , Amplitude de Movimento Articular , Técnicas de Sutura
13.
Nanoscale Res Lett ; 6(1): 193, 2011 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-21711731

RESUMO

The valence band offset (VBO) of wurtzite indium nitride/strontium titanate (InN/SrTiO3) heterojunction has been directly measured by x-ray photoelectron spectroscopy. The VBO is determined to be 1.26 ± 0.23 eV and the conduction band offset is deduced to be 1.30 ± 0.23 eV, indicating the heterojunction has a type-I band alignment. The accurate determination of the valence and conduction band offsets paves a way to the applications of integrating InN with the functional oxide SrTiO3.

14.
Nanotechnology ; 22(23): 235603, 2011 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-21474875

RESUMO

Well-aligned tilted Zn-doped InN nanorods have been grown successfully on r-plane sapphire in a horizontal metal-organic chemical vapor deposition system. All of the nanorods are symmetrically tilted in two opposite directions. X-ray diffraction and transmission electron microscopy measurements show that the nanorods are single-crystalline and have exactly the same epitaxial orientation as the a-plane InN film. The nanorod has a new cross sectional shape of an axial symmetry pentagon and the axis of symmetry is the c-axis of the crystal. Zn dopant plays a crucial role in the growth progress, being an important factor in controlling the morphology of the InN nanomaterials and their properties.

15.
J Nanosci Nanotechnol ; 11(11): 9368-83, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413217

RESUMO

Conduction and valence band discontinuities (band offsets) in the heterojunctions consisting of ZnO/4H-SiC, ZnO/GaAs, MgO/4H-SiC, MgO/AIN, InN/ZnO, InN/GaAs, MgO/InN, and InN/4H-SiC, were precisely determined by X-ray photoelectron spectroscopy (XPS) measurement. As an example, the XPS measurement on the ZnO/4H-SiC heterojunction is described in detail in the beginning of the section of the experiments. We also analyzed several factors which may have impact on the band offset in a practical heterojunction. The deviation in band offset induced by both polar and non-polar heterojunction band bending from the true value was also characterized by taking into account the intrinsic polarization field in the heterojunction consisting of the two polar materials.

16.
Nanoscale Res Lett ; 4(11): 1315-8, 2009 11.
Artigo em Inglês | MEDLINE | ID: mdl-20628470

RESUMO

In the framework of effective-mass envelope function theory, including the effect of Rashba spin-orbit coupling, the binding energy E(b) and spin-orbit split energy Г of the ground state of a hydrogenic donor impurity in AlGaN/GaN triangle-shaped potential heterointerface are calculated. We find that with the electric field of the heterojunction increasing, (1) the effective width of quantum well W̅ decreases and (2) the binding energy increases monotonously, and in the mean time, (3) the spin-orbit split energy Г decreases drastically. (4) The maximum of Г is 1.22 meV when the electric field of heterointerface is 1 MV/cm.

17.
18.
J Phys Chem B ; 112(44): 13898-905, 2008 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-18855434

RESUMO

Using first-principles calculations, the elastic constants, the thermodynamic properties, and the structural phase transition between the B1 (rocksalt) and the B2 (cesium chloride) phases of NaCl are investigated by means of the pseudopotential plane-waves method. The calculations are performed within the generalized gradient approximation to density functional theory with the Perdew-Burke-Ernzerhof exchange-correlation functional. On the basis of the third-order Birch-Murnaghan equation of states, the transition pressure Pt between the B1 phase and the B2 phase of NaCl is determined. The calculated values are generally speaking in good agreement with experiments and with similar theoretical calculations. From the theoretical calculations, the shear modulus, Young's modulus, rigidity modulus, and Poisson's ratio of NaCl are derived. According to the quasi-harmonic Debye model, we estimated the Debye temperature of NaCl from the average sound velocity. Moreover, the pressure derivatives of elastic constants, partial differentialC11/partial differentialP, partial differentialC12/partial differentialP, partial differentialC44/partial differentialP, partial differentialS11/partial differential P, partial differentialS12/partial differentialP, and partial differentialS44/partial differentialP, for NaCl crystal are investigated for the first time. This is a quantitative theoretical prediction of the elastic and thermodynamic properties of NaCl, and it still awaits experimental confirmation.

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