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1.
Nat Commun ; 10(1): 3782, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31439841

RESUMO

Three-dimensional bimetallic nanoframes with high spatial diffusivity and surface heterogeneity possess remarkable catalytic activities owing to their highly exposed active surfaces and tunable electronic structure. Here we report a general one-pot strategy to prepare ultrathin octahedral Au3Ag nanoframes, with the formation mechanism explicitly elucidated through well-monitored temporal nanostructure evolution. Rich crystalline defects lead to lowered atomic coordination and varied electronic states of the metal atoms as evidenced by extensive structural characterizations. When used for electrocatalytic methanol oxidation, the Au3Ag nanoframes demonstrate superior performance with a high specific activity of 3.38 mA cm-2, 3.9 times that of the commercial Pt/C. More intriguingly, the kinetics of methanol oxidation on the Au3Ag nanoframes is counter-intuitively promoted by carbon monoxide. The enhancement is ascribed to the altered reaction pathway and enhanced OH- co-adsorption on the defect-rich surfaces, which can be well understood from the d-band model and comprehensive density functional theory simulations.

2.
J Craniofac Surg ; 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31343590

RESUMO

Conjunctival prolapse may occur following ocular, eyelid, and orbital surgeries. Conjunctival prolapse usually results as a complication of maximal levator resection or cosmetic lower eyelid blepharoplasty. Here, we describe conjunctival prolapse as an unexpected complication of frontalis muscle flap transfer for severe ptosis. On postoperative day 5, the patient experienced upper eyelid swelling after closing his eyes suddenly and standing up abruptly. The conjunctiva was reddish and ballooned up, and they protruded over the eyelids. Conjunctival prolapse persisted until postoperative day 8. The patient and surgeon were concerned that this complication would affect ptosis correction and surgical outcome. U-shaped fixations were placed to suture and force the prolapsed conjunctiva back to their normal anatomical positions. At postoperative 6 months, the patient had not experienced additional issues, and he was satisfied with the appearance of his eyes. This report describes a rare clinical case of conjunctival prolapse and provides a reference for surgeons treating similar complications.

3.
Thorax ; 74(9): 865-874, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31331947

RESUMO

BACKGROUND: Uncontrolled lung inflammation is one of the prominent features in the pathogenesis of lung infection- associated acute lung injury (ALI). Microvesicles (MVs) are extracellular nanovesicles that are generated via direct membrane budding. METHODS: Bronchoalveolar lavage fluid (BALF) samples were collected from mice with or without intratracheal lipopolysaccharide (LPS) instillation. BALF MVs were characterised and MV-containing microRNA (miRNA) profiles were assessed and confirmed. Secretion and function of MV-containing miR-223/142 (MV-miR-223/142) were analysed in vivo. RESULTS: In BALF, MVs are mainly derived from macrophages in response to LPS. After intratracheal instillation (i.t.) of LPS or Klebsiella pneumoniae, MV-containing miR-223/142 are dramatically induced in both BALF and serum. Mechanistically, miRNA 3' end uridylation mediates the packing of miR-223/142 into MVs. To investigate the functional role of MV-miR-223/142, we loaded miR-223/142 mimics into unstimulated MVs and delivered them into the murine lungs via i.t. The miR-223/142 mimics-enriched MVs selectively targeted lung macrophages and suppressed the inflammatory lung responses that were triggered by LPS or K. pneumoniae. Mechanistically, miR-223 and miR-142 synergistically suppress Nlrp3 inflammasome activation in macrophages via inhibition of Nlrp3 and Asc, respectively. CONCLUSIONS: In the pathogenesis of lung macrophage-mediated inflammatory responses, MV-miR-223/142 secretion is robustly enhanced and detectable in BALF and serum. Furthermore, restoration of intracellular miR-223/142 via vesicle-mediated delivery suppresses macrophage activation and lung inflammation via inhibition of Nlrp3 inflammasome activation.

4.
Chem Biol Drug Des ; 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31293023

RESUMO

Due to the potencies in the treatments of cancer, infectious diseases, and autoimmune diseases, the developments of human TLR8 (hTLR8) agonists and antagonists have attracted widespread attentions. The hTLR8 agonists and antagonists have similar structures but with completely opposite biological effects. Up to date, the subtle differences in the structures between the hTLR8 agonists and antagonists are still unknown. In this work, emerging chemical pattern (ECP) was successfully used to extract the key chemical patterns of the hTLR8 agonists and antagonists. By using CAEP classifier, an optimal ECP model with only 3 descriptors was established with the overall prediction accuracy larger than 90%. Further hierarchical cluster analysis and molecular docking showed that the H-bond and hydrophobic properties are the key features distinguishing the hTLR8 agonists from antagonists. Comparing with the antagonists, the agonists show stronger specific H-bond properties, while antagonists have stronger non-specific hydrophobic properties. The significant differences in the structural properties may be closely related to the activation/inhibition mechanism of hTLR8.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31245966

RESUMO

Hysterectomy has been the definitive treatment option for symptomatic adenomyosis and/or adenomyoma when medical or other conservative treatments have failed to control the symptoms. The conservative surgery has already developed as an alternative treatment because of the patients' increasing desire to preserve uterus. This video demonstrates a novel hysteroscopic treatment of symptomatic adenomyoma for the patients without fertility desire.

6.
J Exp Med ; 216(9): 2202-2220, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31235510

RESUMO

Emerging evidence suggests that extracellular vesicle (EV)-containing miRNAs mediate intercellular communications in response to noxious stimuli. It remains unclear how a cell selectively sorts the cellular miRNAs into EVs. We report that caveolin-1 (cav-1) is essential for sorting of selected miRNAs into microvesicles (MVs), a main type of EVs generated by outward budding of the plasma membrane. We found that cav-1 tyrosine 14 (Y14)-phosphorylation leads to interactions between cav-1 and hnRNPA2B1, an RNA-binding protein. The cav-1/hnRNPA2B1 complex subsequently traffics together into MVs. Oxidative stress induces O-GlcNAcylation of hnRNPA2B1, resulting in a robustly altered hnRNPA2B1-bound miRNA repertoire. Notably, cav-1 pY14 also promotes hnRNPA2B1 O-GlcNAcylation. Functionally, macrophages serve as the principal recipient of epithelial MVs in the lung. MV-containing cav-1/hnRNPA2B1 complex-bound miR-17/93 activate tissue macrophages. Collectively, cav-1 is the first identified membranous protein that directly guides RNA-binding protein into EVs. Our work delineates a novel mechanism by which oxidative stress compels epithelial cells to package and secrete specific miRNAs and elicits an innate immune response.

7.
Nat Commun ; 10(1): 2570, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31239437

RESUMO

Searching for actinide decorporation agents with advantages of high decorporation efficiency, minimal biological toxicity, and high oral efficiency is crucial for nuclear safety and the sustainable development of nuclear energy. Removing actinides deposited in bones after intake is one of the most significant challenges remaining in this field because of the instantaneous formation of highly stable actinide phosphate complexes upon contact with hydroxyapatite. Here we report a hydroxypyridinone-based ligand (5LIO-1-Cm-3,2-HOPO) exhibiting stronger affinity for U(VI) compared with the reported tetradentate hydroxypyridinone ligands. This is further revealed by the first principles calculation analysis on bonding between the ligand and uranium. Both in vitro uranium removal assay and in vivo decorporation experiments with mice show that 5LIO-1-Cm-3,2-HOPO can remove uranium from kidneys and bones with high efficiencies, while the decorporation efficiency is nearly independent of the treatment time. Moreover, this ligand shows a high oral decorporation efficiency, making it attractive for practical applications.

8.
ACS Appl Mater Interfaces ; 11(22): 19679-19690, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31081331

RESUMO

Building two-dimensional (2D) and three-dimensional (3D) fibrous structures in the micro- and nanoscale will offer exciting prospects for numerous applications spanning from sensors to energy storage and tissue engineering scaffolds. Electrospinning is a well-suited technique for drawing micro- to nanoscale fibers, but current methods of building electrospun fibers in 3D are restrictive in terms of printed height, design of macroscopic fiber networks, and choice of polymer. Here, we combine low-voltage electrospinning and additive manufacturing as a method to pattern layers of suspended mesofibers. Layers of fibers are suspended between 3D-printed supports in situ in multiple fiber layers and designable orientations. We examine the key working parameters to attain a threshold for fiber suspension, use those behavioral observations to establish a "fiber suspension indicator", and demonstrate its utility through design of intricate suspended fiber architectures. Individual fibers produced by this method approach the micrometer/submicrometer scale, while the overall suspended 3D fiber architecture can span over a centimeter in height. We demonstrate an application of suspended fiber architectures in 3D cell culture, utilizing patterned fiber topography to guide the assembly of suspended high-cellular-density structures. The solution-based fiber suspension patterning process we report offers a unique competence in patterning soft polymers, including extracellular matrix-like materials, in a high resolution and aspect ratio. The platform could thus offer new design and manufacturing capabilities of devices and functional products by incorporating functional fibrous elements.

9.
ACS Appl Mater Interfaces ; 11(24): 21619-21626, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31140771

RESUMO

The nano-MOF+ technique was employed by assembling nanoporous metal-organic framework (MOF) UiO-66 with nanoscale zero-valent iron (ZVI) particles to remove uranyl ions from aqueous solution under anoxic condition for the first time. The synthesized composite of Fe0@UiO-66-COOH exhibits a synergic effect between uranyl sorption by MOF host of UiO-66-COOH and chemical reduction by ZVI, reaching much elevated removal capacity and rate in comparison to those of the pristine UiO-66-COOH. The combined complexation and reduction mechanisms are further elucidated by the synchrotron radiation X-ray absorption near-edge structure analysis. This work highlights the bright future of the nano-MOF+ technique in the application of uranium removal, especially for the remediation of the uranium-contaminated subsurface environment.

10.
Eur J Med Chem ; 177: 171-187, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31132532

RESUMO

Nur77, an orphan member of the nuclear receptor superfamily, plays an important role in the regulation of inflammatory processes. Our previous work found that celastrol, a pentacyclic triterpene, bound to Nur77 to inhibit inflammation in a Nur77-dependent manner. Celastrol binding to Nur77 promotes Nur77 translocation from nucleus to cytoplasm, resulting in clearance of inflamed mitochondria and then alleviation of inflammation. Here, we report the design, synthesis, SAR study and biological evaluation of a series of celastrol analogs. A total of 24 celastrol derivatives were made. Compound 3a with a Kd of 0.87 µM was found to be less toxic than celastrol and could be a hit molecule for further optimization.


Assuntos
Anti-Inflamatórios/farmacologia , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/antagonistas & inibidores , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/toxicidade , Sítios de Ligação , Desenho de Drogas , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/química , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteína Sequestossoma-1/metabolismo , Relação Estrutura-Atividade , Fator 2 Associado a Receptor de TNF/metabolismo , Triterpenos/síntese química , Triterpenos/metabolismo , Triterpenos/toxicidade , Peixe-Zebra
11.
J Immunol ; 202(11): 3267-3281, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31019060

RESUMO

Matrix metalloproteinase (MMP)-8 and -9 released by degranulating polymorphonuclear cells (PMNs) promote pericellular proteolysis by binding to PMN surfaces in a catalytically active tissue inhibitor of metalloproteinases (TIMP)-resistant forms. The PMN receptor(s) to which MMP-8 and MMP-9 bind(s) is not known. Competitive binding experiments showed that Mmp-8 and Mmp-9 share binding sites on murine PMN surfaces. A novel form of TIMP-1 (an inhibitor of soluble MMPs) is rapidly expressed on PMN surfaces when human PMNs are activated. Membrane-bound TIMP-1 is the PMN receptor for pro- and active MMP-8 and -9 as shown by the following: 1) TIMP-1 is strikingly colocalized with MMP-8 and -9 on activated human PMN surfaces and in PMN extracellular traps; 2) minimal immunoreactive and active Mmp-8 or Mmp-9 are detected on the surface of activated Timp-1-/- murine PMNs; and 3) binding of exogenous Timp-1 (but not Timp-2) to Timp-1-/- murine PMNs reconstitutes the binding of exogenous pro-Mmp-8 and pro-Mmp-9 to the surface of Timp-1-/- PMNs. Unlike full-length pro-Mmp-8 and pro-Mmp-9, mutant pro-Mmp proteins lacking the COOH-terminal hemopexin domain fail to bind to Mmp-8-/-x Mmp-9-/- murine PMNs. Soluble hemopexin inhibits the binding of pro-Mmp-8 and pro-Mmp-9 to Mmp-8-/-x Mmp-9-/- murine PMNs. Thus, the COOH-terminal hemopexin domains of pro-Mmp-8 and pro-Mmp-9 are required for their binding to membrane-bound Timp-1 on murine PMNs. Exposing nonhuman primates to cigarette smoke upregulates colocalized expression of TIMP-1 with MMP-8 and MMP-9 on peripheral blood PMN surfaces. By anchoring MMP-8 and MMP-9 to PMN surfaces, membrane-bound TIMP-1 plays a counterintuitive role in promoting PMN pericellular proteolysis occurring in chronic obstructive pulmonary disease and other diseases.

12.
Med Phys ; 46(6): 2621-2628, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30924935

RESUMO

PURPOSE: Respiratory gated four-dimensional (4D) single photon emission computed tomography (SPECT) with phase-matched CT reduces respiratory blurring and attenuation correction (AC) artifacts in cardiac SPECT. This study aims to develop and investigate the effectiveness of an interpolated CT (ICT) method for improved cardiac SPECT AC using simulations. METHODS: We used the 4D XCAT phantom to simulate a population of ten patients varied in gender, anatomy, 99m Tc-sestamibi distribution, respiratory patterns, and disease states. Simulated 120 SPECT projection data were rebinned into six equal count gates. Activity and attenuation maps in each gate were averaged as gated SPECT and CT (GCT). Three helical CTs were simulated at end-inspiration (HCT-IN), end-expiration (HCT-EX), and mid-respiration (HCT-MID). The ICTs were obtained from HCT-EX and HCT-IN using the motion vector field generated between them from affine plus b-spline registration. Projections were reconstructed by OS-EM method, using GCT, ICT, and three HCTs for AC. Reconstructed images of each gate were registered to end-expiration and averaged to generate the polar plots. Relative difference for each segment and relative defect size were computed using images of GCT AC as reference. RESULTS: The average of maximum relative difference through ten phantoms was 7.93 ± 4.71%, 2.50 ± 0.98%, 3.58 ± 0.74%, and 2.14 ± 0.56% for noisy HCT-IN, HCT-MID, HCT-EX, and ICT AC data, respectively. The ICT showed closest defect size to GCT while the differences from HCTs can be over 40%. CONCLUSION: We conclude that the performance of ICT is similar to GCT. It improves the image quality and quantitative accuracy for respiratory-gated cardiac SPECT as compared to conventional HCT, while it can potentially further reduce the radiation dose of GCT.

13.
Mar Drugs ; 17(3)2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893778

RESUMO

Five new ergostanes, penicisteroids D-H (1-5), were isolated from the liquid culture of the deep-sea-derived fungus Penicillium granulatum MCCC 3A00475, along with 27 known compounds. The structures of the new steroids were established mainly on the basis of extensive analysis of 1D and 2D NMR as well as HRESIMS data. Moreover, the absolute configurations of 1 were confirmed unambiguously by the single-crystal X-ray crystallography. Compounds 2 and 4⁻7 showed moderate antiproliferative effects selectively against 12 different cancer cell lines with IC50 values of around 5 µM. Compounds 2 and 6, potent RXRα binders with Kd values of 13.8 and 12.9 µM, respectively, could induce apoptosis by a Retinoid X Receptor (RXR)-α-dependent mechanism by regulating RXRα transcriptional expression and promoting the poly-ADP-ribose polymerase (PARP) cleavage. Moreover, they could inhibit proliferation by cell cycle arrest at the G0/G1 phase.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Organismos Aquáticos/química , Ergosterol/farmacologia , Penicillium/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ensaios de Seleção de Medicamentos Antitumorais , Ergosterol/análogos & derivados , Ergosterol/química , Ergosterol/isolamento & purificação , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Receptor X Retinoide alfa/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Integr Biol (Camb) ; 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30855664

RESUMO

Binding/unbinding kinetics are key determinants of drug potencies. However, there are still a lot of challenges in predicting kinetic properties during early-stage drug development. In this work, position-restrained molecular dynamics simulations combined with energy decomposition were applied to extract protein-ligand interaction (PLI) fingerprints along the unbinding pathway of 20 p38 mitogen-activated protein kinase (p38 MAPK) Type II inhibitors. The results showed that the electrostatic and/or van der Waals interaction fingerprints at three key positions can be used for accurate prediction of the dissociation rate constants (koff) of p38 MAPK Type II inhibitors. The strategy proposed in this paper can provide not only an efficient method of predicting the dissociation rates of the p38 MAPK Type II inhibitors, but also the atom-level mechanism of enthalpy-driven unbinding process.

15.
Langmuir ; 35(12): 4254-4262, 2019 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-30839219

RESUMO

The adsorption processes of ions into charged nanospace are associated with many practical applications. Whereas a large number of microporous materials have been prepared toward efficient adsorption of ions from solutions, theoretical models that allow for capturing the characteristics of ion dynamic adsorption into like-charged nanopores are still few. The difficulty originates from the overlapping of electric potentials inside the pores. Herein, a theoretical model is proposed by incorporating dynamic density functional theory with modified Poisson equation for investigating the dynamic adsorption of ions into like-charged nanoslits. This model is rationalized by comparing the theoretical predictions with corresponding simulation results. Afterward, by analyzing the adsorption dynamics, we show that the overlapping effect is associated with the pore size, ion bulk concentration, and surface charge density, and it plays a dominant role in the coupling between the total adsorption amount of ions and total adsorption time. Specifically, with weak overlapping effect, the total adsorption amount is intuitively proportional to the total adsorption time; however, when the overlapping effect is strong, the total adsorption amount may be inversely proportional to the total adsorption time, indicating that both high adsorption amount and short adsorption time can be achieved simultaneously. This work provides a meaningful insight toward the rational design and optimization of microporous materials for efficient ion adsorption.

16.
J Org Chem ; 84(5): 2922-2932, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30729784

RESUMO

A series of scarce N-alkyl-2,5-unsubstituted/monosubstituted fulleropyrrolidines were synthesized in moderate to excellent yields by the simple one-step thermal reaction of [60]fullerene with primary/secondary amines in the presence of paraformaldehyde without the addition of valuable metal salts. Intriguingly, the reaction with primary amines unexpectedly afforded N-alkyl-2,5-unsubstituted fulleropyrrolidines instead of the anticipated 2,5-monosubstituted fulleropyrrolidines. A plausible reaction pathway is proposed to elucidate the above-mentioned reaction process based on the experimental results.

17.
J Pathol ; 248(1): 77-87, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30632164

RESUMO

Previous studies revealed the increasing risk of tubal pregnancy following failure of levonorgestrel (LNG)-induced emergency contraception, which was attributed to the reduced ciliary motility in response to LNG. However, understanding of the mechanism of LNG-induced reduction in the ciliary beat frequency (CBF) is limited. The transient receptor potential vanilloid (TRPV) 4 channel is located widely in the female reproductive tract and generates an influx of Ca2+ following its activation under normal physiological conditions, which regulates the CBF. The present study aimed to explore whether LNG reduced the CBF in the Fallopian tubes by modulating TRPV4 channels, leading to embryo retention in the Fallopian tubes and subsequent tubal pregnancy. The study provided evidence that the expression of TRPV4 was downregulated in the Fallopian tubes among patients with tubal pregnancy and negatively correlated with the serum level of progesterone. LNG downregulated the expression of TRPV4, limiting the calcium influx to reduce the CBF in mouse oviducts. Furthermore, the distribution of ciliated cells and the morphology of cilia did not change following the administration of LNG. LNG-induced reduction in the CBF and embryo retention in the Fallopian tubes and in mouse oviducts were partially reversed by the progesterone receptor antagonist RU486 or the TRPV4 agonist 4α-phorbol 12,13-didecanoate (4α-PDD). The results indicated that LNG could downregulate the expression of TRPV4 to reduce the CBF in both humans and mice, suggesting the possible mechanism of tubal pregnancy. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

18.
World Neurosurg ; 2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30677575

RESUMO

OBJECTIVE: This meta-analysis was conducted to evaluate the therapeutic effects in clinical and radiologic outcomes of a self-locking stand-alone cage (SSC) and cage-with-plate (CP) for multilevel anterior cervical discectomy and fusion (ACDF). METHODS: A systematic search was performed for all comparative studies reported up to August 2018. Operative time, hospital stay, intraoperative blood loss, Japanese Orthopedic Association score, Neck Disability Index (NDI), cervical and segmental Cobb angle, intervertebral height, fusion rate, incidence of subsidence, dysphagia, and adjacent segment degeneration were analyzed with the RevMan 5.3.3 software. RESULTS: A total of 15 studies were included. There was no difference regarding preoperative or postoperative Japanese Orthopedic Association score, Neck Disability Index, segmental Cobb angle and intervertebral height, preoperative cervical Cobb angle, fusion rate, incidence of subsidence, and adjacent segment degeneration between the SSC and CP group (P > 0.05). However, the SSC group had shorter operative time (mean difference [MD], -11.35; 95% confidence interval [CI], -16.24 to -3.66) and hospital stay (MD, -0.64; 95% CI, -1.21 to -0.06), less intraoperative blood loss (MD, -13.22; 95% CI, -19.03 to -7.41) and postoperative cervical Cobb angle (MD, -0.70; 95% CI, -1.35 to -0.06), and lower incidence of dysphagia significantly (odds ratio, -0.57; 95% CI, 0.40-0.82) (P < 0.05). CONCLUSIONS: ACDF with SSC and CP in multilevel cervical spondylosis achieved similar clinical relief. Although CP maintained better cervical lordosis, SSC contributed to less surgical pain and fewer complications. ACDF with SSC is safe and efficient in treating multilevel cervical spondylosis.

19.
Med Sci Monit ; 25: 547-557, 2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30659165

RESUMO

BACKGROUND Self-locking stand-alone cages (MC+) and cage-with-pate fixation system are 2 different surgical methods used in anterior cervical discectomy and fusion (ACDF), but few systematic comparative studies comparing the 2 methods in treating multilevel cervical spondylotic myelopathy (MCSM) have been published. MATERIAL AND METHODS Sixty-two patients with MCSM who underwent multilevel ACDF were enrolled and completed at least a 3-year postoperative follow-up. The operative time, intra-operative blood loss, and clinical and radiological results were compared between the MC+ self-locking cages group and the cage-with-plate fixation group. Clinical parameters, including VAS for neck pain, Japanese Orthopedic Association (JOA) score, and neck disabled index (NDI), were evaluated. Surgical results according to Odom's criteria and postoperative dysphagia status, C5 nerve root palsy, and loosening of the instrumentation were recorded. Postoperative radiological results, including fusion rates, fusion segmental Cobb's angle (FSC), cervical lordosis, fusion segmental height (FSH), cage subsidence, and adjacent segment degeneration, were assessed. RESULTS The VAS score, JOA score, and NDI score were significantly improved in both groups. However, the patients in the cage-with-plate group were more likely to have neck pain at the last follow-up. The cervical lordosis, FSC, and FSH showed significant correction immediately after surgery. The loss of the cervical lordosis and FSH were higher in the MC+ group. CONCLUSIONS We found that use of MC+ cages is safe and effective in treating MCSM, but for patients who require strong postoperative stabilization and maintaining the cervical alignment better, the cage-with-plate fixation may best.


Assuntos
Discotomia/métodos , Fusão Vertebral/métodos , Espondilose/cirurgia , Adulto , Idoso , Placas Ósseas , Vértebras Cervicais/cirurgia , China , Feminino , Seguimentos , Humanos , Degeneração do Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Cervicalgia/cirurgia , Duração da Cirurgia , Medição da Dor , Radiografia , Estudos Retrospectivos , Doenças da Medula Espinal/cirurgia , Osteofitose Vertebral , Resultado do Tratamento
20.
Environ Sci Technol ; 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30516368

RESUMO

Traditional analytical methods of thorium contamination suffer from several disadvantages such as time-consuming procedure and equipment-intensive nature, leading to substantial challenges in rapid and onsite monitoring of thorium concentration in complex natural water systems. We report here the first case of luminescent metal organic framework based probe (ThP-1) for highly sensitive and selective self-calibrated sensing of Th4+ contamination in natural fresh water media with a notably facilitated detection procedure. The detection limit of ThP-1 was determined to be 24.2 ppb, much lower than the thorium contamination standard of 246 ppb in drinking water defined by the World Health Organization. Importantly, the detection procedure based on the rarely reported self-calibration manner is greatly beneficial on improving the detection accuracy. The self-calibrated luminescence evolution process is of great anti-interference ability capable of detecting thorium contamination in a wide concentration range from 24.2 ppb to 300 ppm, which can not be achieved directly by the traditional methods. The Th4+-selective luminescence response originates from the selective uptake and efficient enrichment of Th4+ by the host framework of ThP-1 through inner-sphere coordination, which is further confirmed by batch experiments, X-ray absorption spectroscopic study, and DFT calculations.

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