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2.
Adv Sci (Weinh) ; : e2400377, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561956

RESUMO

Ligand-protected heterometallic nanoclusters in contrast to homo-metal counterparts show more broad applications due to the synergistic effect of hetero-metals but their controllable syntheses remain a challenge. Among heterometallic nanoclusters, monovalent Ag-Cu compounds are rarely explored due to much difference of Ag(I) and Cu(I) such as atom radius, coordination habits, and redox potential. Encouraged by copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction, comproportionation reaction of Cu(II)X2 and Cu(0) in the presence of (PhC≡CAg)n complex and molybdate generated a core-shell peanut-shaped 66-nuclear Ag(I)-Cu(I) heterometallic nanocluster, [(Mo4O16)2@Cu12Ag54(PhC≡C)50] (referred to as Ag54Cu12). The structure and composition of Ag-Cu heterometallic nanocluster are fully characterized. X-ray single crystal diffraction reveals that Ag54Cu12 has a peanut-shaped silver(I)/copper(I) heterometallic nanocage protected by fifty phenylacetylene ligands in µ3-modes and encapsulated two mutually twisted tetramolybdates. Heterometallic nanocage contains a 54-Ag-atom outer ellipsoid silver cage decorated by 12 copper inside wall. Nanosized Ag54Cu12 is a n-type narrow-band-gap semiconductor with a good photocurrent response. Preliminary experiments demonstrates that Ag54Cu12 itself and activated carbon supported Ag54Cu12/C are effective catalysts for 1,3-dipole cycloaddition between alkynes and azides at ambient conditions. The work provides not only a new synthetic route toward Ag(I)-Cu(I) nanoclusters but also an important heterometallic intermediate in CuAAC catalytic reaction.

3.
J Orthop Surg Res ; 19(1): 249, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637795

RESUMO

PURPOSE: Preoperative anemia increases postoperative morbidity, mortality, and the risk of allogeneic transfusion. However, the incidence of preoperative anemia in patients undergoing total hip arthroplasty and total knee arthroplasty (TKA) and its relationship to postoperative outcomes has not been previously reported. METHODS: We conducted a comprehensive literature search through PubMed, Cochrane Library, Web of Sincien, and Embase from inception to July 2023 to investigate the prevalence of preoperative anemia in patients undergoing Total Joint Arthroplasty, comorbidities between anemic and non-anemicpatients before surgery, and postoperative outcomes. postoperative outcomes were analyzed. Overall prevalence was calculated using a random-effects model, and heterogeneity between studies was examined by Cochran's Q test and quantified by the I2 statistic. Subgroup analyses and meta-regression analyses were performed to identify sources of heterogeneity. Publication bias was assessed by funnel plots and validated by Egger's test. RESULTS: A total of 21 studies with 369,101 samples were included, all of which were retrospective cohort studies. 3 studies were of high quality and 18 studies were of moderate quality. The results showed that the prevalence of preoperative anemia was 22% in patients awaiting arthroplasty; subgroup analyses revealed that the prevalence of preoperative anemia was highest in patients awaiting revision of total knee arthroplasty; the highest prevalence of preoperative anemia was found in the Americas; preoperative anemia was more prevalent in the female than in the male population; and preoperative anemia with a history of preoperative anemia was more common in the female than in the male population. patients with a history of preoperative anemia; patients with joint replacement who had a history of preoperative anemia had an increased risk of infection, postoperative blood transfusion rate, postoperative blood transfusion, Deep vein thrombosis of the lower limbs, days in hospital, readmission within three months, and mortality compared with patients who did not have preoperative anemia. CONCLUSION: The prevalence of preoperative anemia in patients awaiting total joint arthroplasty is 22%, and is higher in TKA and female patients undergoing revision, while preoperative anemia is detrimental to the patient's postoperative recovery and will increase the risk of postoperative complications, transfusion rates, days in the hospital, readmission rates, and mortality.


Assuntos
Anemia , Artroplastia de Quadril , Artroplastia do Joelho , Humanos , Masculino , Feminino , Estudos Retrospectivos , Anemia/etiologia , Artroplastia do Joelho/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Extremidade Inferior
4.
Angew Chem Int Ed Engl ; 63(7): e202318390, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38117040

RESUMO

Luban locks with mortise and tenon structure have structural diversity and architectural stability, and it is extremely challenging to synthesize Luban lock-like structures at the molecular level. In this work, we report the cocrystallization of two structurally related atom-precise fcc silver nanoclusters Ag110 (SPhF)48 (PPh3 )12 (Ag110 ) and Ag14 (µ6 -S)(SPhF)12 (PPh3 )8 (Ag14 ). It is worth noting that the Ag110 cluster is the first compound to simulate the complex Luban lock structure at the molecular level. Meanwhile, Ag110 is the largest known fcc-based silver nanocluster, so far, there is no precedent for fcc silver nanocluster with more than 100 silver atoms. DFT calculations show that Ag110 is a 58-electron superatom with an electronically closed shell1S2 1P6 1D10 2S2 1F14 2P6 1G18 . Ag110 ⋅Ag14 can rapidly catalyze the reduction of 4-nitrophenol within 4 minutes. In addition, Ag110 presents clear structural evidence to reveal the critical size and mechanism of the transformation of metal core from fcc stacking to quasi-spherical superatom. This research work provides an important structural model for studying the nucleation mechanism and structural assembly of silver nanoclusters.

5.
Nanoscale ; 14(12): 4469-4473, 2022 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-35262141

RESUMO

A polyoxometalate-templated thiolate-protected silver nanocluster, [Cu3(Mo4O16)2@Ag55(CyhS)43(CH3O)(COOCF3)]·3H2O, has been isolated under solvothermal conditions. In situ insertion of three Cu2+ ions into two polymolybdate anions generated a new, sandwich-type D3h-symmetric [Cu3(Mo4O16)2]10- polyoxoanion template encapsulated into an Ag55(CyhS)43 shell. The structure and composition of this Ag nanocluster have been fully characterized. This work has provided a new way to develop high-nuclearity metal nanoclusters with various structures.

6.
Inorg Chem ; 60(20): 15136-15140, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34612632

RESUMO

One-dimensional (1D) organic-inorganic hybrid lead halides with unique core-shell quantum wire structures and splendid photoluminescence properties have been considered one of the most promising high-efficiency broadband emitters. However, studies on the broadband emissions in 1D purely face-shared lead iodide hybrids are still rare so far. Herein, we report on a new 1D lead iodide hybrid, (2cepyH)PbI3 (2cepy = 1-(2-chloroethyl)pyrrolidine), characterized with face-sharing PbI6 octahedral chains. Upon UV photoexcitation, this material shows broadband yellow emissions originating from the self-trapped excitons associated with distorted Pb-I lattices on account of the strong exciton-phonon coupling, as proved by variable-temperature emission spectra. Moreover, experimental and calculated results reveal that (2cepyH)PbI3 is an indirect bandgap semiconductor, the band structures of which are governed by inorganic parts. Our work represents the first broadband emitter based on a 1D face-shared lead iodide hybrid and opens a new way to obtain the novel broadband emission materials.

7.
Inorg Chem ; 60(12): 9174-9180, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34081454

RESUMO

Titanium-oxide or polyoxotitanate clusters are a new type of inorganic host materials that can encapsulate inorganic molecules or ions. We report herein a (NH4)4(enH2)[Ti18O27(PhCOO)24(en)9] molecular cage (Ti18) that encapsulates an entire organic ethylenediamine (en) ion. A thorough investigation has revealed the extraordinary versatility of en. Besides being a guest cation, it also functions as chelating and bridging ligand. It balances the charge of the negative Ti18 cage and facilitates the deprotonation of benzoic acid at the early stage of the reaction as well. DFT calculation and a derivative of Ti18 with open sites at its equatorial position shed further light on the formation mechanism. Ti18 strongly absorbs visible light as a result of en coordination, and it exhibits superior photocatalytic activity compared to anatase TiO2.

8.
ACS Appl Mater Interfaces ; 13(17): 20821-20829, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33887905

RESUMO

Two-dimensional (2D) metal-organic frameworks (MOFs) have attracted growing interest due to excellent performance in gas separation, energy conversion and storage, catalysis, and sensing, but their homochirality and exfoliation as well as related enantioselective catalysis and sensing remain a stage of pending exploration owing to the scarcity of homochiral MOFs and intrinsic aggregation of nanosheets. Herein, a homochiral 2D MOF (HMOF-3) with polymeric chirality, good thermostability, and solvent stability is designed and constructed by a homochiral organic ligand 5,5'-((1R,2R)-cyclohexane dicarbonyl bis(azanediyl)) diisophthalic acid (R,R-CHCAIP), a ditopic coligand 4,4'-bipyridine, and Zn salts. Remarkably, HMOF-3 can be exfoliated via solvent-assisted sonication to achieve 2D HMOF-3 nanosheets (HMOF-3-NS), which exhibit a sensitive turn-on effect with the fluorescence enhancement up to 63.5 times in the presence of R/S-mandelic acid, d/l-tartaric acid, d/l-lactic acid, d/l-alanine, and d/l-tryptophan. More importantly, the high surface area, polymeric chirality environment, and highly accessible functional sites on the surface of HMOF-3 nanosheets enable close contact with probed enantiomers, leading to highly enantioselective and sensitive sensing. The turn-on mechanism of host-guest-assisted electronic transfer is confirmed by DFT calculation and the relative experiment. This work highlights the promise of homochiral 2D MOF nanosheets for enantioselective sensing applications.

9.
Zhongguo Gu Shang ; 34(1): 15-9, 2021 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-33666014

RESUMO

OBJECTIVE: To investigate the clinical efficacy and advantage of minimally invasive transforaminal lumbar interbody fusion under microscope-assisted Zista channel in the treatment of degreeⅠandⅡdegenerative lumbar spondylolisthesis. METHODS: The clinical data of 18 patients with degenerative lumbar spondylolisthesis treated by microscope-assisted Zista channel MIS-TLIF operation from January 2017 to March 2018 were analyzed retrospectively. There were 10 males and 8 females with an average age of 59 years (48 to 70). The course of spondylolisthesis ranged from 6 months to 5 years with an average of 33 months. The segment of spondylolisthesis was L4 in 13 casesand L5 in 5 cases. According to Meyerding spondylolisthesis criteria, 11 cases were degreeⅠand 7 cases were degreeⅡ. The perioperative observation indexes were recorded. The VAS score and JOA score of lumbago and leg pain before and after operation were compared to evaluate the clinical efficacy. At 12 months after operation, the height of intervertebral space was measured by imaging data, the intervertebral fusion was evaluated by Brantigan-Steffee standard, and the curative effect was evaluated according to the modified Macnab standard. RESULTS: All the patients completed the operation successfully and were followed up more than 12 months after operation. Operation time was(160.45±34.98) min, intraoperative blood loss was (88.32±21.12) ml, postoperative drainage volume was (50.34 ±18.22)ml, and walking time after operation was (20.65±6.25) h. Preoperative and postoperative at 7 days, 3 months, 12 months, VAS score of low back pain was 7.81±2.16, 4.19±1.17, 2.25±0.62 and 1.53±0.58 respectively, VAS score of leg pain was 8.47± 2.21, 3.45±0.86, 2.31±0.73 and 1.43±0.47, JOA score was 12.01±2.33, 18.56±3.12, 23.54±3.31 and 26.34±2.65. There were significant differences in VAS and JOA scores between preoperative and postoperative (P<0.05). The height of intervertebral space increased from (4.46±0.72) mm preoperative to (10.24±1.48) mm at 12 months after operation (P<0.05). All operative segments got fusion (16 cases of grade E and 2 cases of grade D). According to Macnab standard, 15 cases obtained excellent results, 2 cases good, 1 case fair. CONCLUSION: MIS-TLIF under microscope-assisted Zista channel has obvious minimally invasive advantages in the treatment of degreeⅠandⅡdegenerative lumbar spondylolisthesis, and it is a safe and effective method.


Assuntos
Fusão Vertebral , Espondilolistese , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Retrospectivos , Espondilolistese/cirurgia , Resultado do Tratamento
10.
Arch Virol ; 166(5): 1455-1462, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33704558

RESUMO

During the dengue epidemic in Yunnan Province, China, during 2019, a concurrent outbreak of chikungunya occurred in the city of Ruili, which is located in the southwest of the province, adjacent to Myanmar. As part of this outbreak, three neonatal cases of infection with indigenous chikungunya virus from mother-to-child (vertical) transmission were observed. Isolates of chikungunya virus were obtained from 37 serum samples of patients with chikungunya during this outbreak, and a phylogenetic analysis of these isolates revealed that they belong to the Indian Ocean subclade of the East/Central/South African genotype. The E1 genes of these viruses did not harbor the A226V mutation.


Assuntos
Febre de Chikungunya/virologia , Vírus Chikungunya/isolamento & purificação , Doenças Transmissíveis Emergentes/virologia , Transmissão Vertical de Doenças Infecciosas , Febre de Chikungunya/epidemiologia , Febre de Chikungunya/transmissão , Vírus Chikungunya/classificação , Vírus Chikungunya/genética , China/epidemiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/transmissão , Surtos de Doenças , Feminino , Genoma Viral/genética , Genótipo , Humanos , Masculino , Mutação , Filogenia , RNA Viral/genética , Proteínas Virais/genética
11.
Dalton Trans ; 50(5): 1690-1696, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33443520

RESUMO

Lanthanide metal-organic frameworks (Ln-MOFs) have demonstrated great potential in luminescence sensing and optical anti-counterfeiting. High-security anti-counterfeiting technology is of great importance and requires the development of universal luminescent materials with multiple modes of emission and adjustable photoluminescence. Herein, a 3D red light emission microporous europium(iii) metal-organic framework [Eu3(OH)(1,3-db)2(H2O)4]·3H2O (1) (1,3-db = 1,3-di(3',5'-dicarboxylpheny) benzene) was constructed from a zigzag [Eu3(COO)8] chain and π-electron-rich terphenyl-tetracarboxylate. Notably, the quenched fluorescence of 1 under hydrogen chloride vapor could be recovered upon fuming by a vapor of Et3N. Most strikingly, the strong blue light emission by nitrogen and sulfur co-doped carbon dots (N,S-CDs) could be encapsulated in 1 to generate a dual-emission composite, namely, N,S-CDs@Eu-MOF, which shows solvent-dependent photoluminescence: N,S-CD-related blue luminescence in water and Eu-MOF-related red emission in organic solvents. Taking advantage of the above unique reversible fluorescent behavior, Eu-MOF and N,S-CDs@Eu-MOF are prepared as fluorescent high-security inks to achieve data encryption and decryption on specific flower patterns.

12.
Chemistry ; 27(11): 3753-3760, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33145861

RESUMO

Dimethyl sulfoxide (DMSO) is a universally used solvent in various synthetic reactions, and trace amounts of DMSO residual are often seen on the surface of chemical product. It is difficult to quickly determine whether the residual DMSO is washed completely. This work reports a CdII metal-organic framework (MOF) SXU-4 which can detect trace amounts of DMSO in various solvents. Fluorescence experiments reveal its turn-on fluorescence effect toward DMSO with high selectivity and sensitivity, indicating that it can be used as an effective luminescent probe for rapid chemical product purity detection by testing the washing solution. Crystallographically characterized DMSO loaded SXU-4 (DMSO@SXU-4), in combination with computational results uncover that the enhanced DMSO-MOF conjugation through multiple DMSO-MOF supramolecule interactions and charge rearrangement are the main causes of fluorescence intensification.

13.
Small ; 16(40): e2003824, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32830455

RESUMO

The surface reconstruction of oxygen evolution reaction (OER) catalysts has been proven favorable for enhancing its catalytic activity. However, what is the active site and how to promote the active species generation remain unclear and are still under debate. Here, the in situ synthesis of CoNi incorporated Fe3 N nanotubes (CoNi-Fe3 N) on the iron foil through the anodization/electrodeposition/nitridation process for use of boosted OER catalysis is reported. The synergistic CoNi doping induces the lattice expansion and up shifts the d-band center of Fe3 N, which enhances the adsorption of hydroxyl groups from electrolyte during the OER catalysis, facilitating the generation of active CoNi-FeOOH on the Fe3 N nanotube surface. As a result of this OER-conditioned surface reconstruction, the optimized catalyst requires an overpotential of only 285 mV at a current density of 10 mA cm-2 with a Tafel slope of 34 mV dec-1 , outperforming commercial RuO2 catalysts. Density functional theory (DFT) calculations further reveal that the Ni site in CoNi-FeOOH modulates the adsorption of OER intermediates and delivers a lower overpotential than those from Fe and Co sites, serving as the optimal active site for excellent OER performance.

14.
Zhongguo Gu Shang ; 33(5): 401-5, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32452175

RESUMO

OBJECTIVE: To investigate the clinical efficacy and advantages of the full endoscopic I See technique for the single-segment degenerative lumbar spinal stenosis. METHODS: The clinical data of 38 patients with the single-segment degenerative lumbar spinal stenosis treated by full endoscopic I See technique from January 2017 to March 2018 were analyzed retrospectively. There were 16 males and 22 females, aged from 35 to 79 years with an average of(53.45±12.56) years. Five cases were L3,4, 23 cases were L4,5, 10 cases were L5S1. The clinical efficacy was evaluated by VAS, ODI and Macnab scores. RESULTS: All the patients were followed up for more than 12 months after operation. The length of operation was from 55 to130 (86.0± 17.5) min. Intraoperative blood loss was ranging from 10 to 50 (17±6) ml, and the hospitalization length was from 3 to 7 days with an average of 4.6 days. The VAS scores of low back pain assessed before operation, and 3 d, 3 months, 12 months post operation were 6.67 ±1.25, 3.87 ±1.35, 2.55 ±1.21, 2.05 ±0.97, respectively, and the differences were statistically significant (P < 0.05);VAS scores of leg pain at these time points were 7.85±2.62, 3.31±1.42, 2.02±1.13, 1.85±0.86, respectively, and the differences were statistically significant (P<0.05);ODI scores were 40.32±5.38, 25.76±4.81, 12.66±4.64, 9.32±2.91, respectively, and the differences were statistically significant (P<0.05). Tevaluate the lumbar vertebrae function according to the Macnab criteria, 15 cases obtained excellent results, 19 cases were good, and 4 cases were fair. CONCLUSION: Full endoscopic I See technique is effective in the treatment of single-segment degenerative lumbar spinal stenosis, with the advantages of less trauma, shorter hospital stay, and faster recovery.


Assuntos
Fusão Vertebral , Estenose Espinal , Adulto , Idoso , Descompressão Cirúrgica , Feminino , Humanos , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
15.
Chem Commun (Camb) ; 56(18): 2747-2750, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32022085

RESUMO

A pre-synthetic strategy was developed for the construction of single ion conductive covalent organic frameworks (COFs). A high Li+ conductivity of 1.6 × 10-3 S cm-1 at 273 K was achieved, and single Na+ and K+ COFs were also obtained by using Na+ and K+ salts as monomers according to this synthetic method.

16.
Angew Chem Int Ed Engl ; 59(16): 6507-6512, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31981465

RESUMO

The only feasible access to non-face-centered cubic (FCC) copper was by physical vapor deposition under high vacuum. Now, non-FCC copper is observed in a series of alkynyl-protected Cu53 nanoclusters (NCs) obtained from solution-phase synthesis. Determined by single-crystal X-ray crystallography, the structures of Cu53 (C≡CPhPh)9 (dppp)6 Cl3 (NO3 )9 and its two derivatives reveal an ABABC stacking sequence involving 41 Cu atoms. It can be regarded as a mixed FCC and HCP structure, which gives strong evidence that Cu can be arranged in non-FCC lattice at ambient conditions when proper ligands are provided. Characterization methods including X-ray absorption fine structure, XPS, ESI-MS, UV/Vis, Auger spectroscopy, and DFT calculations were carried out. CuII was shown to successively coordinate with introduced ligands and changed to CuI after bonding with phosphine. The following addition of NaBH4 and the aging step further reduced it to the Cu53 NC.

17.
Neural Regen Res ; 15(2): 242-250, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31552889

RESUMO

Alzheimer's disease is a common progressive neurodegenerative disorder, pathologically characterized by the presence of ß-amyloid plaques and neurofibrillary tangles. Current treatment approaches using drugs only alleviate the symptoms without curing the disease, which is a serious issue and influences the quality of life of the patients and their caregivers. In recent years, stem cell technology has provided new insights into the treatment of neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. Currently, the main sources of stem cells include neural stem cells, embryonic stem cells, mesenchymal stem cells, and induced pluripotent stem cells. In this review, we discuss the pathophysiology and general treatment of Alzheimer's disease, and the current state of stem cell transplantation in the treatment of Alzheimer's disease. We also assess future challenges in the clinical application and drug development of stem cell transplantation as a treatment for Alzheimer's disease.

18.
Int J Surg ; 69: 23-31, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31301432

RESUMO

BACKGROUND: The efficacy of core decompression plus autologous bone mesenchymal stem cells (BMSCs) for the treatment of osteonecrosis of the femoral head (ONFH) remains controversial. We conducted a systematic review and meta-analysis to explore the efficacy of core decompression combined with BMSCs for OFNH patients. METHODS: We searched PubMed, Embase, Web of Science, and the Cochrane library databases through October 2018 for randomized controlled trials (RCTs) assessing the effect of core decompression combined with BMSCs for OFNH patients. The primary outcome was the visual analog scale (VAS) score at 6 months, 12 months and 24 months. The pooled data were analyzed using Stata 12.0 software. RESULTS: Fourteen studies with 540 patients (core decompression + BMSCs = 275, core decompression alone = 265) were included in our meta-analysis. Compared with the core decompression alone group, the core decompression + BMSCs group showed a significant decrease in the VAS score at 6 months, 12 months and 24 months, and a decrease in the number of hips undergoing total hip arthroplasty (THA), the Western Ontario and McMaster Universities (WOMAC) score and the volume of the postoperative necrotic zone. Core decompression + autologous BMSCs was associated with an increase in HHS postoperatively. No significant difference existed in adverse events. CONCLUSIONS: Compared with core decompression alone in the treatment of ONFH, the combined utilization of core decompression and autologous BMSCs has better pain relief and clinical outcomes and can delay the collapse of the femoral head more effectively.


Assuntos
Transplante de Medula Óssea , Descompressão Cirúrgica/métodos , Necrose da Cabeça do Fêmur/terapia , Transplante de Células-Tronco , Adulto , Feminino , Necrose da Cabeça do Fêmur/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo
19.
Pediatr Cardiol ; 40(6): 1144-1150, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31152184

RESUMO

Congenital right atrial appendage aneurysm (RAAA) is an extremely rare malformation that can coexist with atrial tachyarrhythmia. There is no consensus on treatment for this condition. This research aimed to investigate the clinical characteristics and efficacy of surgical resection to treat atrial tachyarrhythmia originating from RAAA in children. Four RAAA children diagnosed with atrial tachyarrhythmia at the age of 1-5.25 years weighing 8.3-17.1 kg were discussed in this retrospective study. Patients underwent various treatments, included electrocardiogram (ECG) and echocardiography, antiarrhythmic medication therapy, radiofrequency catheter ablation (RFCA), surgical resection of RAAA and pathological examinations. The results from these treatments along with clinical features of patients were analyzed. The incidence of RAAA in patients with atrial tachycardia originating from the right or left atrial appendages (RAA or LAA) was 7.3% (4/55). The prevalence of RAAA in the RAA was 12.5% (4/32). Atrial tachyarrhythmia was identified both prenatally (26 and 36 weeks of gestational age) and postnatally (1 and 4 months after birth), with two patients per group, respectively. The RAAAs condition in two patients with atrial tachycardia (AT), concomitant atrial flutter (AF) and atrial fibrillation (Af) was identified using echocardiogram. Although, RAAA in two patients with mono AT was unidentified in echocardiogram and failed to be identified in the procedure of RFCA, RAAA was confirmed during surgical resection of the RAA. Multiple pre-surgical antiarrhythmic medications combined therapy used to treat all four patients showed either no effect at all or was only partially effective. The original atrial tachyarrhythmia was successfully abolished after RAAA surgical resection in four patients. AT originating from new foci was established in two patients post-surgically. The conditions of these two patients were successfully reverted and normal sinus rhythm maintained in the application of antiarrhythmic medications. These results confirmed the efficacy of RAAA surgical resection. The pathology study showed cystic dilation in parts of the atrial cavity, fibrosis of the cyst wall, generalized fibrosis of atrial myocardium with myocardium atrophy and cystic dilation. RAAA is prone to misdiagnosis by echocardiogram. Atrial tachyarrhythmia in patients with RAAA is usually resistant to antiarrhythmic medication therapy and RFCA. Surgical resection of RAAA is a safe and effective option that is minimally invasive.


Assuntos
Apêndice Atrial/cirurgia , Aneurisma Cardíaco/cirurgia , Taquicardia/cirurgia , Antiarrítmicos/uso terapêutico , Apêndice Atrial/anormalidades , Ablação por Cateter/métodos , Pré-Escolar , Ecocardiografia , Feminino , Aneurisma Cardíaco/complicações , Aneurisma Cardíaco/epidemiologia , Humanos , Incidência , Lactente , Masculino , Estudos Retrospectivos , Taquicardia/complicações , Taquicardia/diagnóstico , Taquicardia/tratamento farmacológico , Resultado do Tratamento
20.
Front Chem ; 7: 206, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31001523

RESUMO

Solar water splitting represents one of the most promising strategies in the quest for clean and renewable energy. However, low conversion efficiency, use of sacrificial agents, and external bias for current water splitting system limit its practical application. Here, a gold-sensitized Si/ZnOcore/shell nanowire photoelectrochemical (PEC) cell is reported for efficient solar water oxidation. We demonstrated gold-sensitized n-Si/n-ZnO nanowire arrays exhibited higher energy conversion efficiency than gold-sensitized p-Si/n-ZnO nanowire arrays due to the favorable energy-band alignment characteristics. Without any assistance from an external electrical source and sacrificial reagents, gold-sensitized n-Si/n-ZnO core/shell nanowire array photoanode achieved unbiased water splitting under simulated solar light illumination. This method opens a promising venue to cost-efficient production of solar fuels.

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