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1.
Dalton Trans ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32129387

RESUMO

A series of host-guest materials containing polyoxometalate anions and lanthanide-organic layers have been synthesized and structurally characterized. By anion-π interactions between the anions and the π-acidic naphthalenediimide moieties, the materials emit strong red room-temperature phosphorescence and exhibit reversible photochromism.

2.
Chem Commun (Camb) ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32003370

RESUMO

Anionic POMs prefer to bond with positive metal cations instead of neutral or negative organic ligands. Therefore, it is challenging to synthesize POM-based MOFs, let alone bi-POM-based host-guest MOFs. In this work, an unprecedented bi-POM-based host-guest MOF, Na[Ni(enMe)2]4[Ni(enMe)2(H2O)2]2{[Ni6(µ3-OH)3(enMe)3 (SIP)1.5(B-α-PW9O34)]2[H3PNiW11O40]}·5enMe·33H2O (1), with Ni6-capped [PW9O34] as the node of the host framework and Keggin-type [PNiW11O40] units as the guest was synthesized. 1 showed excellent chemical stability towards aqueous solutions of pH 2-12 at both ambient and boiling temperature, providing opportunities for its application in fresh water harvesting from air.

3.
J Cell Mol Med ; 24(1): 441-450, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31721438

RESUMO

Long non-coding RNAs (lncRNAs) have been reported to participate in the pathogenesis of non-small cell lung cancer (NSCLC). However, how lncRNA deleted in lymphocytic leukaemia 2 (DLEU2) contributes to NSCLC remains undocumented. The clinical significance of lncRNA DLEU2 and miR-30a-5p expression in NSCLC was analysed by using fluorescence in situ hybridization and TCGA cohorts. Gain- and loss-of-function experiments as well as a NSCLC tumour model were executed to determine the role of lncRNA DLEU2 in NSCLC. DLEU2-sponged miR-30a-5p was verified by luciferase reporter, and RIP assays. Herein, the expression of lncRNA DLEU2 was elevated in NSCLC tissues, and its high expression or low expression of miR-30a-5p acted as an independent prognostic factor of poor survival and tumour recurrence in NSCLC. Silencing of lncRNA DLEU2 repressed the tumorigenesis and invasive potential of NSCLC, whereas re-expression of lncRNA DLEU2 showed the opposite effects. Furthermore, lncRNA DLEU2 harboured a negative correlation with miR-30a-5p expression in NSCLC tissues and acted as a sponge of miR-30a-5p, which reversed the tumour-promoting effects of lncRNA DLEU2 by targeting putative homeodomain transcription factor 2 in NSCLC. Altogether, lncRNA DLEU2 promoted the tumorigenesis and invasion of NSCLC by sponging miR-30a-5p.

4.
J Thorac Dis ; 11(8): 3578-3583, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31559064

RESUMO

Background: With the popularization of minimal invasive surgery, video-assisted thoracoscopic surgery (VATS) is gradually replacing conventional thoracotomy for lung cancer and is even used for osteosarcoma patients with pulmonary metastasis. In this study, we characterized the need for open surgery by comparing computer tomography (CT) diagnosis and postoperative pathology of patients with pulmonary metastases of osteosarcoma. Methods: A retrospective analysis was carried out on patients with underwent surgery for pulmonary metastatic osteosarcoma admitted to our hospital between January 2008 and July 2018. The numbers of pulmonary metastatic nodules suspected by preoperative CT scan were calculated in addition to the number of nodules which were resected and pathologically confirmed to be metastatic during surgery. The Spearman correlation coefficient between the number of nodules on preoperative CT scan and the number of lesions pathologically confirmed was calculated. Results: In total, 69 patients undergoing 96 thoracotomy operations were included in this study. The median interval between preoperative CT examination and operation was 7 days (range, 1-44 days). The median number of the suspected nodules on preoperative CT and the pathologically positive metastases resected during operation were 1 and 3, respectively. Remarkably, 36 (37.5%) thoracotomies revealed that more metastatic nodules were detected during thoracotomy than preoperative CT scans. Conclusions: Preoperative CT examination omits a few small pulmonary metastases of osteosarcoma and there is rare progress in recent years. Therefore, we recommend that patients with pulmonary metastases of undergo thoracotomy to locate and resect all metastases as much as possible through intraoperative direct palpation.

5.
J Thorac Dis ; 11(Suppl 8): S1044-S1048, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31205761

RESUMO

Rib fracture is the most common injury in chest trauma. Chest wall stabilization (CWS) has been employed in China for 10 years and has been recognized as a safe and practical technique for rib fracture therapy. A survey entitled "Surgical Treatment for Rib Fractures" was launched at the beginning of 2018 showing that 95.6% of the hospitals surveyed performed CWS in over 30,000 cases in the past 2 years. Despite the large volume of CWS performed in China, we discovered the following characteristics: lack of large-scale clinical research, and standardized recognition of surgical indications, high costs incurred for surgical consumables, and undefined professional standard. We revealed that most of the researches on CWS in China have room for improvement. The Shanghai Sixth People's Hospital has conducted a series of CWS researches in patients with multi-rib fractures whose results showed shorter therapeutic time, pain reduction, lower morbidity, and improvement in lung function. Consequently, we formulated our own surgical indications for CWS. Thoracoscopic-assisted minimally invasive CWS surgery had been conducted in several hospitals in China. Undoubtedly, the continuous improvement of equipment and surgical techniques will inevitably lead to its further development. Researches on materials with superior absorbability or tissue compatibility have been successfully conducted in China. However, the lack of multi-center and large-sample randomized controlled trials has been one of the key factors that hampered the accurate evaluation of CWS. Accordingly, a nationwide study entitled "Evaluation of the effectiveness of surgical fixation of multiple rib fractures-a multi-center and ambispective cohort study" was initiated in June 2018. It is believed that the result of this research would considerably improve and enrich the clinical evidence on CWS in rib fracture patients.

6.
J Colloid Interface Sci ; 551: 10-15, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071491

RESUMO

Due to the superior capacity for lithium storage, metallic tin and germanium are considered as one of the candidate anodes for the next generation of lithium ion batteries. Herein, metallic tin and germanium particles are successfully prepared by using a mild replacement reaction between metallic sodium and the corresponding tetrachloride under room temperature. The as-obtained metals exhibit nanocrystals of several nanometers. Used as anode of lithium-ion batteries, the as-obtained metallic nanocrystals display improved cycling stability, superior rate performance and high reversible capacity as well. Furthermore, it provides a facile approach to fabricate other electrochemically active metallic nanocrystals by using this mild and environmental benignity replacement reaction.

7.
J Colloid Interface Sci ; 542: 263-268, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30763893

RESUMO

A facile and cost-effective method to prepare defect-rich MoS2 nanosheets is developed via an electrochemical exfoliation process. By using bucket-like metallic titanium mesh both as inert anode and container for MoS2 powders, defect-rich thin MoS2 nanosheets can be fast exfoliated from the bulk powders in aqueous sodium sulfate electrolyte under positive potentials. The as-obtained MoS2 nanosheets exhibit excellent cycling capability, high specific capacity, and superior rate performance for lithium storage. Furthermore, it provides a novel and effective method to exfoliate insulative or semiconductive layer-structured bulk powders into defect-rich 2D nanosheets.

8.
Ann Thorac Surg ; 107(2): e119-e120, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30081030

RESUMO

Studies have confirmed that, for severe flail chest or sternal fractures and even multiple rib fractures, surgical treatment can effectively reduce hospital stay and relieve chest wall pain. However, fixation of multiple costal cartilage fractures in such a small area is a challenge if an internal fixator is simply placed directly on the sternum. This case report shares a method of simultaneous fixation of multiple costal cartilage and sternal fractures through a small incision, and it is also appropriate for multiple costal cartilage fractures without sternal fracture.


Assuntos
Cartilagem Costal/lesões , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Fraturas de Cartilagem/cirurgia , Esterno/lesões , Tórax Fundido/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Esterno/cirurgia
9.
Conf Proc IEEE Eng Med Biol Soc ; 2019: 1492-1495, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31946176

RESUMO

OBJECTIVE: This study concentrates on subtle electrocardiogram (ECG) spatiotemporal characteristics in the repolarization phase, and describes a deterministic learning-based methodology for the detection of abnormal cardiac dynamics induced by ischemia. METHODS: ST-T complex of the surface 12-lead ECG signals are identified and extracted. Cardiac dynamics underlying ST-T complex signals is captured using deterministic learning algorithm. This kind of dynamics information represents the beat-to-beat temporal change of electrophysiological modifications in ventricular repolarization, which is shown to be sensitive to the variance during myocardial ischemia. Cardiodynamicsgram (CDG) is proposed as the three-dimensional graphic representation of cardiac dynamics information. RESULTS: Encouraging evaluation results are achieved on electrocardiograms from public PTB database and hospital patients. Significant correlations are found between the CDG morphology and ischemia. CONCLUSION: Anormal dynamics of cardiac repolarization during ischemia can be detected using a deterministic learning-based methodology. The extracted cardiac dynamics information within routine ECG is expected to provide early detection for latent ischemia before obvious pathological changes are present in ECG. SIGNIFICANCE: The proposed techniques can be considered as a complementary tool to the generally accepted ECG method for detection of abnormal dynamics in cardiac repolarization, which are important for identifying patients at risk of myocardial ischemia.


Assuntos
Doença da Artéria Coronariana , Isquemia Miocárdica , Algoritmos , Eletrocardiografia , Coração , Humanos
10.
Biochemistry ; 57(51): 7011-7020, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30499668

RESUMO

Deeper exploration of uncharacterized Gcn5-related N-acetyltransferases has the potential to expand our knowledge of the types of molecules that can be acylated by this important superfamily of enzymes and may offer new opportunities for biotechnological applications. While determining native or biologically relevant in vivo functions of uncharacterized proteins is ideal, their alternative or promiscuous in vitro capabilities provide insight into key active site interactions. Additionally, this knowledge can be exploited to selectively modify complex molecules and reduce byproducts when synthetic routes become challenging. During our exploration of uncharacterized Gcn5-related N-acetyltransferases from Pseudomonas aeruginosa, we identified such an example. We found that the PA3944 enzyme acetylates both polymyxin B and colistin on a single diaminobutyric acid residue closest to the macrocyclic ring of the antimicrobial peptide and determined the PA3944 crystal structure. This finding is important for several reasons. (1) To the best of our knowledge, this is the first report of enzymatic acylation of polymyxins and thus reveals a new type of substrate that this enzyme family can use. (2) The enzymatic acetylation offers a controlled method for antibiotic modification compared to classical promiscuous chemical methods. (3) The site of acetylation would reduce the overall positive charge of the molecule, which is important for reducing nephrotoxic effects and may be a salvage strategy for this important class of antibiotics. While the physiological substrate for this enzyme remains unknown, our structural and functional characterization of PA3944 offers insight into its unique noncanonical substrate specificity.


Assuntos
Antibacterianos/metabolismo , Proteínas de Bactérias/metabolismo , Colistina/metabolismo , Acetiltransferases N-Terminal/metabolismo , Polimixina B/metabolismo , Acetilação , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Cristalografia por Raios X , Genes Bacterianos , Cinética , Modelos Moleculares , Acetiltransferases N-Terminal/química , Acetiltransferases N-Terminal/genética , Conformação Proteica , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/genética , Especificidade por Substrato
11.
J Cardiothorac Surg ; 13(1): 124, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30526640

RESUMO

OBJECTIVE: To investigate the methods and clinical efficacy of reconstruction of chest defects with titanium sternal fixation system after the surgical resection of sternal tumors. METHODS: A total of 6 patients with sternal tumor who were diagnosed and underwent resection and repair of the chest wall defects by titanium plates system, from 2017.3 to 2017.11 in our hospital were reviewed. Their pathological types, surgical reconstruction methods, follow-up results were analyzed. RESULTS: Six cases of sternal tumor were completely resected and the sternums were reconstructed with titanium sternal fixation system. There was no operative death, postoperative chest wall deformity, abnormal breathing or complications of respiratory circulation. After 3 to 10 months of follow-up, there was no loose screw or plate exposure. Not only the thoracic appearances were good, but patients' satisfaction was high. CONCLUSIONS: Surgical resection is the best treatment for sternal tumors, no matter it is benign or malignant. Titanium sternal fixation system combine with other soft materials can reconstruct the chest wall well after resection, and this technique is efficient as well as easy to learn.


Assuntos
Adenocarcinoma Folicular/cirurgia , Neoplasias Ósseas/cirurgia , Placas Ósseas , Condrossarcoma/cirurgia , Tumor de Células Gigantes do Osso/cirurgia , Doença de Hodgkin/cirurgia , Procedimentos Cirúrgicos Reconstrutivos/métodos , Esterno/cirurgia , Parede Torácica/cirurgia , Adenocarcinoma Folicular/secundário , Adulto , Neoplasias Ósseas/secundário , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Período Pós-Operatório , Retorno ao Trabalho , Neoplasias da Glândula Tireoide/patologia , Titânio , Resultado do Tratamento
12.
Int J Mol Sci ; 19(10)2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30332774

RESUMO

C-terminal tensin-like protein (CTEN) is a member of tensin family, which is crucial for the assembly of cell-matrix adhesome. Unlike other tensins, CTEN is selectively expressed only in a few tissues such as the prostate. However, the biological relevance of CTEN in normal prostate is poorly understood. In this study, we revealed that CTEN is selectively expressed in the prostate epithelial cells and enriched in the basal compartment. Knockdown of CTEN in RWPE-1 cells suppresses cell proliferation and results in G1/S cell cycle arrest as well as the accumulation of cyclin-dependent kinase (CDK) inhibitors, p21 and p27. Moreover, the expression of CTEN is decreased during acinar morphogenesis using Matrigel-based three-dimensional (3D) culture. In the course of acinar formation, induction of CTEN reactivates focal adhesion kinase (FAK) Y397 phosphorylation and disrupts the acini structure. This study, to our knowledge, is the first report demonstrating that downregulation of CTEN is required for luminal differentiation and acinar formation.


Assuntos
Células Acinares/citologia , Células Acinares/metabolismo , Regulação para Baixo , Morfogênese , Próstata/citologia , Próstata/crescimento & desenvolvimento , Tensinas/metabolismo , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Integrina beta1/metabolismo , Masculino , Ligação Proteica , Proteína rhoA de Ligação ao GTP/metabolismo
13.
Langmuir ; 34(22): 6621-6627, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29750533

RESUMO

Polyvinylidene fluoride (PVDF) membranes are limited in the field of oil-in-water emulsion treatment because the intrinsic hydrophobicity of PVDF can cause serious membrane fouling. Here, a superhydrophilic PVDF membrane (PVDF@PDA-GSH) was fabricated using a facile, versatile, mussel-inspired method. The pristine PVDF membrane was coated with dopamine under mild alkaline conditions by a dip-coating method, followed by addition of glutathione (GSH) via a simple reaction. GSH was successfully coated onto the membrane surface and confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectrometry. Hierarchical surface structure and superhydrophilicity were examined by scanning electron microscopy and contact angle, respectively, giving the PVDF@PDA-GSH membrane excellent wettability and antifouling ability. The water flux of PVDF@PDA-GSH was several-fold higher than conventional filtration membranes, and the oil rejection ratio was nearly 99%. The PVDF@PDA-GSH membrane also showed favorable reusability because the flux recovery ratio (FRR) remained above 90% after five cycles. In general, these results indicated that this modification might provide a good method for the fabrication of superhydrophilic PVDF membranes with good prospects for water filtration applications.


Assuntos
Técnicas de Química Analítica/métodos , Membranas Artificiais , Peptídeos/química , Polivinil/química , Emulsões/isolamento & purificação , Água/química
14.
J Colloid Interface Sci ; 521: 11-16, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29547784

RESUMO

Defect-rich, boron (B) and nitrogen (N) dual-doped and inert BN covalent bonds-free graphenes (BNGs) can be successfully synthesized via a method of two-step doping combined with chemical etching. B and N doping degree and surface areas of BNGs can be enhanced facilely by chemical etching without forming inert covalent BN bonds. The as-obtained porous BNGs deliver more superior electro-catalytic activity for oxygen reduction reaction than the unetched BNGs and commercial Pt/C catalysts.

15.
J Org Chem ; 83(2): 1033-1040, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29260559

RESUMO

A cationic palladium(II)-catalyzed reductive cyclization of cyclohexadienone-containing 1,6-enynes by using ethanol as a hydrogen donor and solvent was successfully developed. This procedure offers convenient access to cyclohexenone-annulated heterocycles under mild reaction conditions. The reaction was initiated by hydropalladation of the alkyne and was quenched by addition of the intramolecular conjugate alkene. This possible mechanism was preliminarily demonstrated by deuterium-labeling experiments.

16.
Tetrahedron Lett ; 58(20): 1973-1975, 2017 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-28966404

RESUMO

The interaction of various 1,2-dibromides with NEt3 under various conditions (THF and DMF, respectively) at different temperatures was investigated. Our results from these reactions show that substrate dependent dehydrobrominations compete with reductive debrominations. A comprehensive discussion of these competitive pathways is offered.

17.
Tetrahedron Lett ; 58(40): 3894-3896, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28966405

RESUMO

cis-ß-Bromostyrene derivatives were synthesized stereospecifically from cinnamic acids through ß-lactone intermediates. The synthetic sequence did not require the purification of the ß-lactone intermediates although they were found to be stable and readily purified in most cases.

18.
J Cardiothorac Surg ; 12(1): 22, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28376814

RESUMO

BACKGROUND: This study aim to evaluate surgical procedures for titanium plate internal fixation of sternal fractures with displacement or nonunion. METHODS: From January 2010 to December 2014, 64 patients with sternal fractures were treated with titanium plate internal fixation in the thoracic surgery department of the Shanghai Sixth People's Hospital. Pain severity scale scores were analyzed preoperatively and postoperatively. All the patients had a 2-month follow-up for treatment evaluation. RESULTS: The mean hospital length of stay was 16.89 days. Forty-five patients underwent surgery for combined injuries. A statistically significant difference (P < 0.05) was found between preoperative and postoperative pain severity scores (7.74 ± 0.89 vs. 3.80 ± 0.79, respectively). At follow-up, healing of the nonunion or fracture was confirmed in all the cases. CONCLUSION: The rigid titanium plate application ensured a safe and easy management of traumatic sternal fractures and nonunion with a good prognosis as compared with other methods.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Esterno/cirurgia , Traumatismos Torácicos , Titânio , Adulto , Idoso , Feminino , Seguimentos , Fraturas Ósseas/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Esterno/lesões , Fatores de Tempo , Tomografia Computadorizada por Raios X , Adulto Jovem
19.
Am J Cardiol ; 119(5): 698-704, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28017302

RESUMO

Cardiodynamicsgram (CDG) has emerged recently as a noninvasive spatiotemporal electrocardiographic method for subtle cardiac dynamics information analysis within electrocardiogram (ECG). This study sought to evaluate the clinical utility of CDG for early coronary artery disease (CAD) detection in suspected patients with CAD presenting with nondiagnostic ECGs. A total of 421 suspected patients with CAD presenting with nondiagnostic ECG were enrolled. Standard 12-lead ECG and CDG were performed simultaneously, 1 day before invasive coronary angiography. Diagnostic accuracy of CDG for early CAD detection was assessed with reference to coronary angiography as the gold standard. Coronary angiography showed ≥1 coronary arteries stenosis of >50% in 347 patients. Of these 347 patients with CAD, 294 patients were positive in CDG. Of 74 non-CAD controls, 63 patients were negative in CDG. Diagnostic accuracy of CDG at presentation for CAD was 84.6%, sensitivity 84.7%, and specificity 83.7%. In patients presenting with nondiagnostic ECGs, an abnormal status can be detected early through noninvasive CDG. CDG is highly sensitive for the early diagnosis of CAD. Underlying causes of false-negative CDG findings included number of diseased coronary arteries and collateral circulation. Subtle myocardial damage that was not detectable on coronary angiography might be the major cause of false-positive findings.


Assuntos
Doença da Artéria Coronariana/diagnóstico , Estenose Coronária/diagnóstico , Vetorcardiografia/métodos , Idoso , Circulação Colateral , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Eletrocardiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Análise Espaço-Temporal
20.
Tetrahedron Lett ; 57(19): 2097-2099, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27110042

RESUMO

Phosphonohydrazines were prepared in good yield from corresponding arylamines by a one-pot reaction through diazotization with an organic nitrite and treatment with a trialkyl phosphite. The trialkyl phosphite is postulated to function as a nucleophile as well as a reducing agent.

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