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1.
EFORT Open Rev ; 9(6): 556-566, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38828976

RESUMO

Objective: Through meta-analysis, this study aims to comprehensively evaluate the efficacy of single-plating and double-plating in the treatment of comminuted fractures of the distal femur. Methods: Computer searches of PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), China Biology Medicine (CBM), VIP, and Wanfang digital journals were performed, and the timeframe for the searches was from the establishment of each database to July 2023 for each of the databases. Meta-analysis was performed using RevMan 5.4 software provided by the Cochrane Library, and the review process was registered in the PROSPERO database. Results: A total of ten studies were included for statistical analysis. One randomised controlled study and nine retrospective cohort studies with a total of 563 patients were included. The double-plate group was superior to the single-plate group in terms of knee mobility at 6 months postoperatively, overall postoperative complications, and the rate of healing of knee deformity. However, it increased the operation time and intraoperative bleeding, and the difference between the two groups was statistically significant (P < 0.05). There was no significant difference between the two groups in terms of excellent knee function rate, fracture healing time, plate fracture, postoperative infection, delayed fracture healing, and non-union (P ≥ 0.05). Conclusion: Double plate fixation for comminuted fractures of the distal femur can improve knee mobility at 6 months postoperatively, reduce overall postoperative complications, and decrease the incidence of malunion healing. However, it increases operative time and bleeding. Randomised studies are needed to provide strong evidence in the future.

2.
BMJ Open ; 13(12): e077974, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38101828

RESUMO

OBJECTIVES: Carcinosarcoma (CS) is a rare and biphasic malignancy characterised by a highly invasive biological nature and poor prognosis. This study explored the epidemiology, site-specific characteristics and survival outcome of CS. DESIGN: We conducted a retrospective study in the Surveillance, Epidemiology and End Results (SEER) database (1975-2018) for primary CS. SETTING AND PARTICIPANTS: SEER database includes publicly available information from regional and state cancer registries in the US centres. A total of 5042 CS patients were identified. We selected the top five anatomic CS (uterus, double adnexa, lung, bladder and breast) patients for further analysis. PRIMARY OUTCOME MEASURES: Incidence was estimated by geographical region, age, sex, race, stage and primary site. Trends were calculated using joinpoint regression. The cancer-specific survival (CSS) rate and initial treatment were summarised. RESULTS: Nearly 80% of CS occurred in the uterus and double adnexa, followed by lung, bladder and breast. The elderly and black population presented the highest age-adjusted rate of CS. The rates of distant metastasis in CS progressively increased from 1989 to 2018. Atlanta was the area with the highest incidence at 0.7 per 100 000. Pulmonary and bladder CS more frequently occurred in men and were diagnosed with regional stage. Distant metastasis was mostly found in ovary/fallopian tube CS. Radiotherapy was more commonly applied in uterine CS, while adnexa CS cases were more likely to receive chemotherapy. Multiple treatments were more used in breast CS. Pulmonary CS seemed to suffer worse CSS (median: 9.92 months), for which radiotherapy might not provide survival benefits (HR 0.60, 95% CI 0.42 to 0.86). Compared with the common histological types in each site, CS had the shortest survival. CONCLUSIONS: CS has unique clinical features in each primary site. Substantial prognosis variances exist based on tumour locations. The aggressive course is the common feature in CS at all sites.


Assuntos
Carcinossarcoma , Sarcoma , Masculino , Feminino , Humanos , Idoso , Estudos Retrospectivos , Programa de SEER , Sistema de Registros , Prognóstico , Carcinossarcoma/epidemiologia , Carcinossarcoma/terapia
3.
J Asian Nat Prod Res ; 24(3): 238-244, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33890531

RESUMO

Phytochemical investigation on the 90% EtOH extract of the seeds of Cipadessa cinerascensa led to the isolation of three new limonoids, cinerascenoids A-C (1-3). Structural elucidation of all the compounds were performed by spectral methods such as 1 D and 2 D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy. All the limonoids were in vitro evaluated for their antimicrobial activities against six pathogenic microorganisms. Limonoids 1 and 2 exhibited some activities against three Gram negative bacteria with MIC values less than 60 µg/ml.


Assuntos
Anti-Infecciosos , Limoninas , Meliaceae , Anti-Infecciosos/farmacologia , Limoninas/farmacologia , Estrutura Molecular , Sementes
4.
J Phys Chem Lett ; 11(6): 2277-2283, 2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32125156

RESUMO

A central difficulty in the design of molecular electronics is poor control of the contact state between the molecule and metal electrode, which may induce instability and noise in logic and memory devices and even destroy the intrinsic functionality of the device. Here, we theoretically propose a simple and effective strategy for realizing full control of the contact state of organic molecules coated on the metal surface by applying homogeneous surface strain. As exemplified by pyrazine molecules on Cu(111), application of compressive (tensile) strain causes the molecules to uniformly adopt the physisorbed (chemisorbed) state. Within the framework of non-equilibrium Green's function calculations, we show that the two distinct contact states yield simultaneous rectification and switching behaviors. Because the contact states of all surface-bound molecules are transformed uniformly via surface strain perturbations, fully controlled collective switching and rectification effects can be simultaneously achieved in this contact system.

6.
Nanoscale ; 11(36): 17010-17017, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31498345

RESUMO

The search for metal-free catalysts for oxygen reduction reactions (ORRs) in energy storage and conversion devices, such as fuel cells and metal-air batteries, is highly desirable but challenging. Here, we have designed and synthesized controllable 3D nitrogen and phosphorous co-doped holey graphene foams (N,P-HGFs) as a high-efficiency ORR catalyst through structural regulation and electronic engineering. The obtained catalyst shows a half-wave potential of 0.865 V in alkaline electrolytes. It is found that Zn-air batteries with the N,P-HGFs-1000 air electrode exhibit excellent discharge performance and durability. Our study suggests that the remarkable ORR performance of N,P co-doped graphene is mainly due to the graphite N-C-P structure, where an enhanced charge density and increased HOMO energy level are confirmed by both experimental results and theoretical density-functional theory calculations.

7.
J Asian Nat Prod Res ; 20(8): 727-733, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30010405

RESUMO

Phytochemical investigation on the stems of Schisandra glaucescens resulted into the isolation of three new lanostane triterpenoids, 12-hydroxyschiglausin B (1), 12-hydroxykadsuphilactone B (2), and 20R-hydroxyschinalactone C (3). Structural elucidation of all the compounds was accomplished by spectral methods. The isolated compounds were tested in vitro for cytotoxic activities. As a result, triterpenoids 1 and 2 showed cytotoxic activities for all six tested tumor cell lines with IC50 values less than 15 µM.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Lanosterol/farmacologia , Caules de Planta/química , Schisandra/química , Triterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , China , Ensaios de Seleção de Medicamentos Antitumorais , Carpóforos , Humanos , Lanosterol/química , Espectroscopia de Ressonância Magnética , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray , Triterpenos/química
8.
J Phys Condens Matter ; 26(39): 395002, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25138270

RESUMO

The stabilities and electronic properties of SrZrO3 (1 1 0) (1  ×  1) polar terminations were investigated systematically by the first-principles density functional theory method. Five possible polar surfaces, i.e. O-deficient, O-rich, stoichiometric, SrO-rich and SrO-deficient ones, were considered. The calculated results indicated that the charge neutralization and polarity compensation condition could be achieved by charge redistributions of surface atoms. For the O-deficient (1 1 0) termination, some filled electronic states were separated from the original conduction bands, while a surface reconstruction was found for the O-rich (1 1 0) surface. The remaining three (1 1 0) terminations remained insulated. Furthermore, a stability diagram involving seven different terminations was constructed using the surface grand potential technique, in which the effect of the chemical environment was included. The calculated results indicated that three (1 1 0) (O-rich, SrO-rich and stoichiometric) and 2 (0 0 1) (ZrO2 and SrO) terminations could be stabilized in distinct areas, whereas the O-deficient surface was unstable within the whole region. Finally, we drew a comparison of stability behaviors between SrZrO3 (1 1 0) (1  ×  1) polar surfaces and the counterparts of ATiO3 (A = Ba, Pb, Sr) and BaZrO3 materials.

9.
Phys Rev Lett ; 107(24): 245501, 2011 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-22243011

RESUMO

van der Waals (vdW) energy corrected density-functional theory [Phys. Rev. Lett. 102, 073005 (2009)] is applied to study the cohesive properties of ionic and semiconductor solids (C, Si, Ge, GaAs, NaCl, and MgO). The required polarizability and dispersion coefficients are calculated using the dielectric function obtained from time-dependent density-functional theory. Coefficients for "atoms in the solid" are then calculated from the Hirshfeld partitioning of the electron density. It is shown that the Clausius-Mossotti equation that relates the polarizability and the dielectric function is accurate even for covalently-bonded semiconductors. We find an overall improvement in the cohesive properties of Si, Ge, GaAs, NaCl, and MgO, when vdW interactions are included on top of the Perdew-Burke-Ernzerhof or Heyd-Scuseria-Ernzerhof functionals. The relevance of our findings for other solids is discussed.

10.
J Comput Chem ; 30(12): 1785-98, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19090567

RESUMO

The structural and electronic properties of five terminations of cubic lead titanate (PbTiO3) (110) polar surface were investigated by first-principles total-energy calculations using a periodic slab model. On the PbTiO termination, an anomalous filling of conduction band was observed, whereas on the O2 termination, two surface oxygen atoms formed a peroxo group, demonstrating that the electronic structures of the two stoichiometric terminations undergo significant changes with respect to bulk materials. However, for the three nonstoichiometric TiO-, Pb-, and O-terminated surfaces, their electronic structures are very similar to bulk. Charge redistribution results for the five terminations confirmed that electronic structure and surface composition changes are responsible for their polarity compensation. However, which mechanism actually dominates the stabilization process depends upon energetic considerations. A thermodynamic stability diagram suggested that the two stoichiometric terminations are unstable; however, the three nonstoichiometric terminations can be stabilized in some given regions. Furthermore, this study indicates that the very different stabilities and surface states filling behaviors of the PbTiO3 (110) polar surface with respect to SrTiO3 and BaTiO3 ones seem to originate from the partially covalent characteristics of Pb-O pairs.

11.
World J Gastroenterol ; 10(21): 3230-3, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15457583

RESUMO

AIM: To determine and compare the effect of vagus nerve on gallbladder motility in patients with hepatic cirrhosis before and after portal azygous disconnection (PAD). METHODS: PAD operation (or Hassab's operation) was performed on 18 patients with portal hypertension, and anterior and posterior vagal trunks were cut. On d 3 before operation and d 10 after operation, (99m)Tc-EHIDA 185 MBq was administered intravenously to the patients, and scintigraphy was performed at 0.25 min/frame. A standard fat meal was administered 30 min after scintigraphy, and dynamic imaging was performed 60 min after the fat meal. Following appearance of the region of interest (ROI) in gallbladder, the time-activity curve of ROI was established. The following seven parameters were used: radioactivity at 30 min after injection of (99m)Tc-EHIDA (RC 30 min), bile emptying fraction (EF), bile emptying period (EP), emptying rate (ER), latent period (LP), latent period radiocounting increment (LI), and latent period radiocounting increment rate (LR). RESULTS: The RC 30 min decreased significantly after operation, compared with that before operation (2 693.6+/- 2 406.9 vs 5 606.8+/-2 625.4, P<0.05). The radiocounting of gallbladder increased gradually during LP. LP after operation was significantly longer than that before operation (13.36+/-5.92 vs 2.24+/-1.48, P<0.01). LI and LR after operation were significantly higher than those before operation (2 861.62+/-028.3 vs 331.21+/-421.02, and 113.42+/-49.52 vs 7.57+/-10.75, respectively, both P<0.01). EP after operation was significantly shorter than that before operation (18.5+/-6.3 vs 24.1+/-6.4, P<0.05). EF and ER after operation were significantly lower than those before operation (13.1+/-5.4 vs 32.3+/-16.3, and 0.7+/-0.3 vs 1.4+/-0.8, respectively, both P<0.01). CONCLUSION: PAD operation is a good clinical model in studying the effect of vagus on gallbladder motility. The gallbladder tension after PAD operation decreases significantly during the interdigestive phase. The latent period of gallbladder contraction prolongs and the motility weakens apparently after a standard fat meal. Human vagus influences the gallbladder motility, and cutting of the nerve inhibits the gallbladder motility.


Assuntos
Esvaziamento da Vesícula Biliar , Hipertensão Portal/cirurgia , Cirrose Hepática/cirurgia , Esplenectomia , Vagotomia , Veia Ázigos/cirurgia , Feminino , Humanos , Hipertensão Portal/fisiopatologia , Cirrose Hepática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Veia Porta/cirurgia , Artéria Esplênica/cirurgia , Nervo Vago/fisiologia , Nervo Vago/cirurgia
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