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1.
Dalton Trans ; 49(7): 2168-2175, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31995077

RESUMO

Experimentally observed magnetic properties are usually statistically averaged from bulk materials and information associated with the local chemical environment cannot be specified. Against this backdrop, we propose a theoretical strategy to provide an in-depth understanding of the multi-role for metrics that may contribute to the apparent magnetic moment of iron borides. In particular, we demonstrate this strategy through systematic manipulation of the iron/boron stoichiometry of six prototype iron borides to tune their associated local structural and electronic environment to further modulate the resultant magnetic moment. The local coordinative structures of the six iron borides were resolved utilizing bond valence analysis by taking the different coordination shells into account. Furthermore, the local electronic properties of each Fe atom in these iron borides, such as charge transfer, electronic distribution, bonding feature and orbital energy level, were carefully analyzed by Bader analysis, density of states analysis and Crystal Orbital Hamilton Population analysis. From the combination of analyses of both the coordinative and electronic properties of the prototype iron borides, a linear relationship between the local magnetic moment and the bond valence as well as the average energy of the Fe 3d orbitals has been confirmed.

2.
J Chromatogr A ; : 460869, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31959456

RESUMO

Prostaglandins (PGs) are vitally important unsaturated fatty acids involved in arachidonic acid (AA) metabolism, participating in numerous pathophysiological processes, especially in maintaining the homeostasis of uterus. Therefore, quantitative analysis of PGs is of great importance for uncovering potential mechanisms of PGs related diseases. However, methods for determining PGs in uterine samples have not been reported. In this study, an ultra high-performance liquid chromatography/mass spectrometry (UHPLC-MS/MS) method was established to quantify PGs in uterine samples, using N,N-Dimethylethylenediamine (DMED) and N,N-Diethylethylenediamine (DEED) as derivatization reagents. The derivatization could be finished at 37 °C for 30 min catalyzed by 1-N,N,N',N'-Tetramethyl-O-(7-azabenzotriazol-1-yl) uronium hexafluorophosphate (HATU). This is a mild condition suitable for most of biological samples. The DMED labeling of PGs could significantly enhance their response compared to those of underived ones. This method exhibited excellent linearity (R2 > 0.997) and precision for the determination of PGs in uterine samples (CV ≤ 12.9%). The extraction recoveries of PGs were ranged from 83.0 to 100% and matrix effects were ranged from 86.3 to 106%, indicating DEED labeled standards could be used as internal standards for PGs quantification. With the proposed method, we successfully quantified PGs in rat uterus. The results showed their levels were significant changed in abnormal uterine bleeding (AUB) rats, suggesting that PGs might be involved in the pathological process of AUB. This established analogous reagents derivatization based UHPLC-MS/MS method could be used as a powerful tool to monitor PGs, providing insights to the precise mechanism of PG action on the endometrium.

3.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(1): 37-40, 2020 Jan 15.
Artigo em Chinês | MEDLINE | ID: mdl-31939232

RESUMO

Objective: To evaluate the short-term effectiveness of the first ray tri-plane osteotomy and other metatarsal basal osteotomy in treatment of hallux valgus with moderate and severe metatarsus adductus. Methods: Between February 2012 and September 2016, 10 patients (12 feet) of hallux valgus with moderate and severe metatarsus adductus were admitted and treated with the first ray tri-plane osteotomy and other metatarsal basal osteotomy and lateral soft tissue release. There were 1 male (2 feet) and 9 females (10 feet) with an average age of 34.5 years (range, 21-55 years). The disease duration ranged from 3 to 10 years (mean, 5.8 years). The degree of metatarsal adductus was moderate in 4 feet and severe in 8 feet according to modified Sgarlato measurement method. Preoperative American Orthopaedic Foot and Ankle Society (AOFAS) score was 46.4±9.3. The metatarsus adductus angle (MAA) was (25.41±3.66)°, hallux valgus angle (HVA) was (41.42±9.67)°, and the first-second intermetatarsal angle (1-2IMA) was (10.72±2.26)°. Results: All incisions healed by first intention. All patients were followed up 18-24 months, with an average of 21.4 months. One patient (1 foot) had metastatic metatarsalgia after operation, but the symptoms disappeared after symptomatic treatment. X-ray re-examination showed that all osteotomies healed, and the healing time was 2.4-3.2 months, with an average of 2.8 months. At last follow-up, MAA was (8.42±0.71)°, HVA was (13.29±1.03)°, 1-2IMA was (4.41±0.48)°, and AOFAS score was 89.8±5.9. There were significant differences in clinical and radiographic indexes between pre- and post-operation ( P<0.05). Conclusion: The first ray tri-plane osteotomy combined with other metatarsal basal osteotomy has a significant short-term effectiveness in the treatment of hallux valgus with moderate and severe metatarsus adductus.


Assuntos
Hallux Valgus , Ossos do Metatarso , Metatarso Varo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia , Resultado do Tratamento , Adulto Jovem
4.
G3 (Bethesda) ; 10(2): 839-848, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-31792004

RESUMO

A trispecific hybrid, MTP (hereafter called tripsazea), was developed from intergeneric crosses involving tetraploid Zea mays (2n = 4x = 40, genome: MMMM), tetraploid Tripsacum dactyloides (2n = 4x = 72, TTTT), and tetraploid Z perennis (2n = 4x = 40, PPPP). On crossing maize-Tripsacum (2n = 4x = 56, MMTT) with Z perennis, 37 progenies with varying chromosome numbers (36-74) were obtained, and a special one (i.e., tripsazea) possessing 2n = 74 chromosomes was generated. Tripsazea is perennial and expresses phenotypic characteristics affected by its progenitor parent. Flow cytometry analysis of tripsazea and its parents showed that tripsazea underwent DNA sequence elimination during allohexaploidization. Of all the chromosomes in diakinesis I, 18.42% participated in heterogenetic pairing, including 16.43% between the M- and P-genomes, 1.59% between the M- and T-genomes, and 0.39% in T- and P-genome pairing. Tripsazea is male sterile and partly female fertile. In comparison with previously synthesized trihybrids containing maize, Tripsacum and teosinte, tripsazea has a higher chromosome number, higher seed setting rate, and vegetative propagation ability of stand and stem. However, few trihybrids possess these valuable traits at the same time. The potential of tripsazea is discussed with respect to the deployment of the genetic bridge for maize improvement and forage breeding.

5.
iScience ; 22: 123-132, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31765993

RESUMO

Flagellated bacteria move collectively in a swirling pattern on agar surfaces immersed in a thin layer of viscous "swarm fluid," but the role of this fluid in mediating the cooperation of the bacterial population is not well understood. Herein, we use gold nanorods (AuNRs) as single particle tracers to explore the spatiotemporal structure of the swarm fluid. Individual AuNRs are moving in a plane of ∼2 µm above swarms, traveling for long distances in high speed without interferences from bacterial movements. The particles are lifted and transported by collective mixing of small vortices around bacteria during localized clustering and de-clustering of motile cells. Their motions fit the Lévy walk model, revealing efficient fluidic flows above the swarms. These flows provide obstacle-free highways for long-range material transportations, allow swarming bacteria to perform population-level communications, and imply the essential role of the fluid phase on the emergence of large-scale synergy.

6.
Metabolism ; 101: 153993, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31672442

RESUMO

BACKGROUND: Therapies targeting altered activity of pyruvate dehydrogenase (PDH) and pyruvate carboxylase (PC) have been proposed for hepatomas. However, the activities of these pathways in hepatomas in vivo have not been distinguished. Here we examined pyruvate entry into the tricarboxylic acid (TCA) cycle through PDH versus PC in vivo using hepatoma-bearing rats. METHODS: Hepatoma-bearing rats were generated by intrahepatic injection of H4IIE cells. Metabolism of 13C-labeled glycerol, a physiological substrate for both gluconeogenesis and energy production, was measured with 13C NMR analysis. The concentration of key metabolites and the expression of relevant enzymes were measured in hepatoma, surrounding liver, and normal liver. RESULTS: In orthotopic hepatomas, pyruvate entry into the TCA cycle occurred exclusively through PDH and the excess PDH activity compared to normal liver was attributed to downregulated pyruvate dehydrogenase kinase (PDK) 2/4. However, pyruvate carboxylation via PC and gluconeogenesis were minimal, which was linked to downregulated forkhead box O1 (FoxO1) by Akt activity. In contrast to many studies of cancer metabolism, lactate production in hepatomas was not increased which corresponded to reduced expression of lactate dehydrogenase. The production of serine and glycine in hepatomas was enhanced, but glycine decarboxylase was downregulated. CONCLUSIONS: The combination of [U-13C3]glycerol and NMR analysis enabled investigation of multiple biochemical processes in hepatomas and surrounding liver. We demonstrated active PDH and other related metabolic alterations in orthotopic hepatomas that differed substantially not only from the host organ but also from many earlier studies with cancer cells.


Assuntos
Carcinoma Hepatocelular/metabolismo , Gluconeogênese , Neoplasias Hepáticas/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Animais , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13/métodos , Carcinoma Hepatocelular/enzimologia , Ciclo do Ácido Cítrico , Glicerol/metabolismo , Fígado/enzimologia , Neoplasias Hepáticas/enzimologia , Ratos
7.
Nat Commun ; 10(1): 4431, 2019 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570716

RESUMO

The design of cheap, non-toxic, and earth-abundant transition metal catalysts for selective hydrogenation of alkynes remains a challenge in both industry and academia. Here, we report a new atomically dispersed copper (Cu) catalyst supported on a defective nanodiamond-graphene (ND@G), which exhibits excellent catalytic performance for the selective conversion of acetylene to ethylene, i.e., with high conversion (95%), high selectivity (98%), and good stability (for more than 60 h). The unique structural feature of the Cu atoms anchored over graphene through Cu-C bonds ensures the effective activation of acetylene and easy desorption of ethylene, which is the key for the outstanding activity and selectivity of the catalyst.

8.
ACS Appl Mater Interfaces ; 11(31): 27717-27726, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31298025

RESUMO

The development of cost-effective catalysts with both high activity and selectivity for carbon-oxygen bond activation is a major challenge and has important ramifications for making value-added chemicals from carbon dioxide (CO2). Herein, we present a one-step pyrolysis of metal organic frameworks that yields highly dispersed cobalt nanoparticles embedded in a carbon matrix which shows exceptional catalytic activity in the reverse water gas shift reaction. Incorporation of nitrogen into the carbon-based supports resulted in increased reaction activity and selectivity toward carbon monoxide (CO), likely because of the formation of a Mott-Schottky interface. At 300 °C and a high space velocity of 300 000 mL g-1 h-1, the catalyst exhibited a CO2 conversion rate of 122 µmolCO2 g-1 s-1, eight times higher than that of a reference Cu/ZnO/Al2O3 catalyst. Our experimental and computational results suggest that nitrogen-doping lowers the energy barrier for the formation of formate intermediates (CO2* + H* → COOH* + *), in addition to the redox mechanism (CO2* + * → CO* + O*). This enhancement is attributed to the efficient electron transfer at the cobalt-support interface, leading to higher hydrogenation activity and opening new avenues for the development of CO2 conversion technology.

9.
Dalton Trans ; 48(32): 12272-12278, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31339138

RESUMO

An extremely large displacement of the indium site in In-S6 octahedra in LnOInS2 (Ln = La, Ce, and Pr) was found in synchrotron X-ray diffraction. LaOInS2 with off-center indium in In-S6 octahedra exhibited a wider optical band gap than CeOInS2 and PrOInS2 with on-center indium. Therefore, the electronic structure of LnOInS2 is governed by the indium site with an extremely large displacement. All LnOInS2 produced H2 gas under visible light irradiation in the presence of sacrificial electron donors.

10.
Phytomedicine ; 63: 153011, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31301538

RESUMO

BACKGROUND: Ilexgenin A (IA), the main bioactive compound from Ilex hainanensis Merr., has significant hypolipidemic activities. However, the effects of IA on colitis-associated colorectal cancer (CRC) and its mechanisms are still unknown. PURPOSE: The study was designed to evaluate the effect of IA on CRC and explore its underlying mechanisms. STUDY DESIGN: The effect of IA on colitis related CRC were evaluated in azoxymethane (AOM)/dextran sulfate sodium (DSS) mice and the underlying mechanisms were revealed by metabolomics, which were further validated in vivo and in vitro. METHODS: The Balb/c mice were treated with AOM/DSS to induce CRC model and fed with normal diet with or without 0.02% IA. After the experimental period, samples of plasma were collected and analyzed by ultra-high-performance liquid chromatography/quadrupole time off light mass spectrometry (UHPLC-Q-TOF). Multivariate statistical tools were used to identify the changes of serum metabolites associated with CRC and responses to IA treatment. HT 29 and HCT 116 cells were stimulated by palmitate (PA) and cultured under hypoxia. Western blot, Q-PCR, and Immunofluorescence staining were performed to confirm the molecular pathway in vivo and in vitro. RESULTS: Our results showed IA significantly inhibited the inflammatory colitis symptoms such as disease activity index score, shortening of colon tissues and the increase of inflammatory cytokines. In metabolomic study, 31 potential metabolites associated with CRC were identified and 24 of them were reversed by IA treatment. Most of biomarkers were associated with arachidonic acid metabolism, glycerophospholipid catabolism, and phospholipid metabolism, suggesting lipid metabolism might be involved in the beneficial effect of IA on CRC. Furthermore, we also found IA could decrease the expressions of SREBP-1 and its target gene in the colon tissues of AOM/DSS mice. It could down-regulate the triglyceride (TG) content and the expressions of HIF1α, SREBP-1, FASN, and ACC in HT 29 and HCT 116 cells. The inhibitory effect of IA on SREBP-1 was also attenuated by desferrioxamine (DFX), suggesting HIF1α is involved in the regulation of IA on SREBP-1. CONCLUSION: IA prevents early colonic carcinogenesis in AOM/DSS mice and reprogramed lipid metabolism partly through HIF1α/SREBP-1.


Assuntos
Neoplasias Colorretais/prevenção & controle , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triterpenos/farmacologia , Animais , Anticarcinógenos/farmacologia , Azoximetano/toxicidade , Colite/induzido quimicamente , Colite/complicações , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/patologia , Sulfato de Dextrana/toxicidade , Células HCT116 , Células HT29 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/genética , beta Catenina/genética
11.
ACS Appl Mater Interfaces ; 11(33): 29858-29867, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31343150

RESUMO

Conversion of straight-chain paraffins into aromatics is particularly attractive but extremely challenging in the oil refining industry. Constructing the Pt-supported catalysts with high aromatic selectivity is vital. Here, we report a strategy to use Fe-modified KL zeolites to improve the Pt atom utilization efficiency and anchor them inside KL zeolite channels via atomic-layer deposition technique. A combination of highly dispersed single-atom Pt and electron-rich Pt clusters is fabricated on the KL zeolite through the creation of proper nucleation sites. The resulted catalyst (PtFe-1/KL) exhibits excellent performance for the n-heptane aromatization (90.1% aromatic selectivity) with an apparent activation energy of 131 kJ/mol and much enhanced stability at a relatively lower temperature (420 °C). Experimental analysis and density functional theory calculation demonstrate that the single-atom Pt might play a key role in the initial dehydrogenation of n-heptane to 1-heptene, and the superior stable Pt clusters encapsulated inside Fe-decorated KL zeolite channels accelerate the 1-heptene dehydrocyclization to aromatics. The synergetic interaction between single-atom Pt and Pt clusters enables the PtFe-1/KL catalyst to be one of the most effective n-heptane aromatization catalysts reported to date.

12.
J Sci Med Sport ; 22(10): 1074-1078, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208828

RESUMO

OBJECTIVES: To systematically evaluate the effects of matrix metalloproteinase-3 (MMP3) and tissue inhibitor of metalloproteinase-2 (TIMP2) on chronic Achilles tendinopathy (AT) susceptibility. Chronic AT is one of the most prevalent and severe injuries in athletes. Early studies suggested that tendon extracellular matrix (ECM) may be involved in the pathogenesis of chronic AT. MMP3 is an important member of the MMP family and is important to ECM integrity. In addition, tissue inhibitor of metalloproteinase-2 (TIMP2) can indirectly limit the activity of MMP3 activity. DESIGN: Case-control genetic association study. METHODS: A total of 1084 chronic AT patients and 2188 controls with Chinese Han ancestry were recruited. Twenty-one SNPs, 4 mapped to MMP3 and 17 mapped to TIMP2, were selected and genotyped. Genetic association analyses and eQTL analyses were performed. In addition, we also examined the potential effects of epistasis using a case-only study design. RESULTS: Two SNPs, rs679620 (OR=0.82, P=0.0006, MMP3) and rs4789932 (OR=1.2, P=0.0002, TIMP2) were identified to be significantly associated with chronic AT risk. No significant results were obtained from epistasis analyses. SNP rs4789932 was identified to be strongly associated with the gene expression level of TIMP2 in two types of human tissues: atrial appendage (P=0.0003) and tibial artery (P=0.0009). CONCLUSIONS: We have identified genetic polymorphisms in MMP3 and TIMP2 to be significantly associated with chronic AT risk. Further eQTL analyses indicated that SNP rs4789932 of TIMP2 was related to the gene expression levels of TIMP2. These results suggest important roles for MMP3 and TIMP2 in the pathophysiology of chronic AT.


Assuntos
Tendão do Calcâneo/fisiopatologia , Metaloproteinase 3 da Matriz/genética , Tendinopatia/genética , Inibidor Tecidual de Metaloproteinase-2/genética , Grupo com Ancestrais do Continente Asiático , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
13.
Ann Vasc Surg ; 60: 236-245, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31200041

RESUMO

BACKGROUND: The goal of this study is to evaluate the safety and efficacy of a novel catheter for right radial artery approach cerebral angiography. METHODS: Patients from the Neurology Department of The Second Affiliated Hospital of Guangxi Traditional Chinese Medical University who underwent diagnostic cerebral angiography of either the left vertebral artery dominant type or balanced type were enrolled in this study. RESULTS: A total of 167 patients were treated between February 2016 and December 2017, of whom 44 were excluded based on study exclusion criteria and 123 were enrolled in the present analysis. Bilateral subclavian artery catheterization and bilateral common carotid artery catheterization were conducted successfully in all 123 patients. The success rate of selective catheterization of the left vertebral artery was 87.8% (108/123). The success rate of selective catheterization of the right vertebral artery using the novel catheter was 89.0% (73/82). The average fluoroscopy time was 6.5 ± 3.4 min, the average operation duration was 47 ± 3.7 (range 50-90) min, and the average dosage of contrast agent was 112.3 ± 8.1 mL. One patient exhibited an absence of pulse in the punctual radial artery after the removal of the arterial compression band, but there was no evidence of ischemia of the distal hand. One patient who was undergoing dual anti-platelet drug treatment suffered from bleeding at the puncture point when deflated for 2 hr after operation; this patient was re-pressurized and re-timed. CONCLUSIONS: This novel catheter improved the success rate of selective left vertebral artery catheterization, and allowed for simplification of the relevant surgical steps. The controllability of this novel catheter was satisfactory, and its associated surgical risk was found to be low.


Assuntos
Artéria Carótida Primitiva , Cateterismo Periférico/instrumentação , Angiografia Cerebral/instrumentação , Transtornos Cerebrovasculares/diagnóstico por imagem , Artéria Radial , Artéria Subclávia , Dispositivos de Acesso Vascular , Artéria Vertebral , Idoso , Idoso de 80 Anos ou mais , Artéria Carótida Primitiva/diagnóstico por imagem , Cateterismo Periférico/efeitos adversos , Angiografia Cerebral/efeitos adversos , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Artéria Radial/diagnóstico por imagem , Fatores de Risco , Artéria Subclávia/diagnóstico por imagem , Artéria Vertebral/diagnóstico por imagem
14.
Toxicol Appl Pharmacol ; 378: 114600, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150656

RESUMO

Corosolic acid (CRA) has been widely used as a food supplement. However, its pharmacokinetic behavior still needs to be explored. In this study, the absorption of CRA in stomach and intestine were investigated by in situ gastric absorption and in situ single-pass perfusion, respectively. Furthermore, the metabolites of CRA in rat plasma, bile, and urine were identified by UPLC-QTOF-MS. The enzymes responsible for its metabolism were explored by rat liver microsome (RLMs). The effects of plasma containing metabolites on cancer cell growth and glucose consumption were evaluated by HT29 and HepG2 cells receptively. The results showed that CRA absorption rate is approximately 20% to 40% in stomach. It has similar absorption rate constant (Ka) in duodenum/jejunum/ileum/colon. However, its effective permeability (Peff) in ileum at 9 µg/mL is significantly higher than the Peff in colon. Moreover, five possible metabolites were identified in plasma and bile, suggesting CRA could be metabolized through methyl carboxylation, hydroxylation, methyl aldehyde substitution, glucuronidation, and acetylation in vivo. Meanwhile, CYP1A2 and CYP3A4 were found to participate in its metabolism. The plasma containing metabolites of CRA significantly inhibited the growth of HT29 colon cancer cells and stimulated glucose consumption of HepG2 cells. Taken together, these results demonstrated that CRA has good absorption in both stomach and small intestine, but it could be metabolized partly due to CYP1A2 and CYP3A4 in vivo. Its metabolites might be responsible for the excellent anti-cancer and anti-diabetes activities of CRA. This study will provide evidence for further CRA development.

15.
J Orthop Surg Res ; 14(1): 120, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060592

RESUMO

BACKGROUND: An increased preoperative talar tilt (TT) angle was reported to be positively correlated with treatment failure after supramalleolar osteotomy (SMOT) for varus ankle osteoarthritis. Distraction arthroplasty was reported to have the ability to correct increased TT angles. The purpose of the current study was to compare the outcomes between SMOT with and without medial distraction arthroplasty (MDA) in the treatment of varus ankle osteoarthritis with increased TT angles. METHODS: We retrospectively reviewed the functional outcomes and radiological findings of 34 patients who underwent SMOT with or without MDA for varus ankle osteoarthritis with increased TT angles. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and Ankle Osteoarthritis Scale (AOS) scores were used for functional evaluation. The tibial anterior surface (TAS) angle, talar tilt (TT) angle, tibial medial malleolar (TMM) angle, talocrural (TC) angle, tibial lateral surface (TLS) angle, and hindfoot alignment (HFA) angle were evaluated preoperatively and at the time of the last follow-up. RESULTS: In the SMOT group, the AOFAS score and AOS pain and function scores were significantly improved (P < 0.01 for each) at a mean follow-up of 61 months. The TAS, TT, TC, TLS, and HFA angles were all significantly improved (P < 0.01 for each). Similarly, in the SMOT with MDA group, the AOFAS score, AOS pain and function scores, and the TAS, TT, TC, TLS, and HFA angles were all significantly improved postoperatively (P < 0.01 for each). When comparing the two groups, the postoperative TT angle was significantly smaller in the SMOT with MDA group (P = 0.023) than in the SMOT group. In addition, the failure rate of TT angle correction was significantly higher in the SMOT group (P = 0.016) than in the SMOT with MDA group. CONCLUSION: SMOT is a promising procedure for functional improvement and malalignment correction for varus ankle osteoarthritis, even in patients with increased talar tilt. If SMOT is combined with MDA, there can be an improvement in the correction of the increased talar tilt. LEVEL OF EVIDENCE: Level III, a retrospective comparative study.


Assuntos
Articulação do Tornozelo/cirurgia , Artroplastia/métodos , Osteoartrite/cirurgia , Osteotomia/métodos , Tálus/cirurgia , Adulto , Idoso , Articulação do Tornozelo/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico por imagem , Estudos Retrospectivos , Tálus/diagnóstico por imagem , Adulto Jovem
16.
J Chem Theory Comput ; 15(6): 3654-3665, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31117479

RESUMO

With the development of theoretical and computational chemistry, as well as high-performance computing, molecular simulation can now be used not only as a tool to explain the experimental results but also as a means for discovery or prediction. Quantum chemical nanoreactor is such a method which can automatically explore the chemical process based only on the basic mechanics without prior knowledge of the reactions. Here, we present a new method which combines the semiempirical quantum mechanical density functional tight-binding (DFTB) method with the nanoreactor molecular dynamic (NMD) method, and we simulated the reaction process of graphene synthesis via detonation at different oxygen/acetylene mole ratios. The formation of graphene is initiated by the breaking of acetylene (C2H2) molecules by collision into pieces such as H atoms, ethynyl (HC≡C•), and vinylidene (H2C═C:) radicals. It is followed by the formation of long straight carbon chains coupled with a few branched carbon chains, which then turned into  a 2-D framework made of carbon rings. Trace oxygen could modulate the size of the rings during graphene formation and promote the formation of regular graphene with fused six-membered rings as we see, but the addition of high oxygen content makes more C-containing species oxidized to small oxide molecules instead of polymerization. The calculation speed of the DFTB nanoreactor is greatly improved compared to the ab initio nanoreactor, which makes it a valuable option to simulate chemical processes of large sizes and long time scales and to help us uncover the "unknown unknowns".

17.
J Magn Reson ; 301: 102-108, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30861456

RESUMO

This study was designed to determine the effects of deuteration in pyruvate on exchange reactions in alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and flux through pyruvate dehydrogenase (PDH). Although deuteration of a 13C enriched substrate is commonly used to increase the lifetime of a probe for hyperpolarization experiments, the potential impact of kinetic isotope effects on such substitutions has not been studied in detail. Metabolism of deuterated pyruvate was investigated in isolated rat hearts. Hearts were perfused with a 1:1 mixture of [U-13C3]pyruvate and [2-13C1]pyruvate or a 1:1 mixture of [U-13C3]pyruvate plus [2-13C1, U-2H3]pyruvate for 30 min before being freeze clamped. Another set of hearts received [2-13C1, U-2H3]pyruvate and was freeze-clamped at 3 min or 6 min. Tissue extracts were analyzed by 1H and 13C{1H} NMR spectroscopy. The chemical shift isotope effect of 2H was monitored in the 13C NMR spectra of the C2 resonance of lactate and alanine plus the C5 of glutamate. There was little kinetic isotope effect of 2H in pyruvate on flux through PDH, LDH or ALT as detected by the distribution of 13C, but the distribution of 2H differed markedly between alanine and lactate. At steady-state, alanine was a mixture of deuterated species, while lactate was largely perdeuterated. Consistent with results at steady-state, hearts freeze-clamped at 3 min or 6 min showed rapid removal of deuterium in alanine but not in lactate. Metabolism of hyperpolarized [1-13C1]pyruvate was compared to [1-13C1,U-2H3]pyruvate in isolated hearts. Consistent with the results from tissue extracts, there was little effect of deuteration on the kinetics of appearance of lactate, alanine or bicarbonate, but there was a small, time-dependent upfield chemical shift in the HP[1-13C1]alanine signal reflecting exchange of methyl deuterons with water protons. Together, these results demonstrate that (1) the kinetics of pyruvate metabolism in hearts detected by 13C NMR are not affected by replacement of the pyruvate methyl protons with deuterons and (2) that the loss of deuterium from the methyl position occurs rapidly during the conversion of pyruvate to alanine. The majority of the deuterium atoms are lost on the time-scale of a hyperpolarization experiment.

18.
Phytochem Anal ; 30(4): 437-446, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30816611

RESUMO

INTRODUCTION: As sources of Rhizoma Paridis are facing shortages, utilising the aerial parts of Paris polyphylla has emerged as a promising additional source. However, the components in the aerial parts still need to be explored, and it is difficult to distinguish the aerial parts of P. polyphylla Smith var. yunnanensis (PPY) and P. polyphylla var. chinensis (PPC), two varieties of P. polyphylla. OBJECTIVE: This study aimed to establish a comprehensive platform to characterise steroid saponins from the aerial parts of PPY and PPC and to discriminate these two varieties. METHODOLOGY: A dereplication approach and ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS) analysis were used for the characterisation of steroidal saponins in the aerial parts of PPY and PPC. Multivariate statistical analysis was performed to differentiate these two varieties and screen discriminant variables. In addition, a genetic algorithm-optimised for support vector machines (GA-SVM) model was developed to predict P. polyphylla samples. The distribution of steroidal saponins in PPY and PPC was visualised by a heatmap. RESULTS: A total of 102 compounds were characterised from the aerial parts of PPY and PPC by dereplication. A clear separation of PPY and PPC was achieved, and 35 saponins were screened as marker compounds. The established GA-SVM model showed excellent prediction performance with a prediction accuracy of 100%. CONCLUSIONS: Many steroid saponins that have been reported in Rhizoma Paridis also exist in the aerial parts of P. polyphylla. Samples from the aerial parts of PPY and PPC could be discriminated using our platform.


Assuntos
Melanthiaceae/química , Fitosteróis/química , Saponinas/química , Cromatografia Líquida de Alta Pressão , Análise de Dados , Espectrometria de Massas , Análise Multivariada , Fitosteróis/isolamento & purificação , Componentes Aéreos da Planta/química , Saponinas/isolamento & purificação
19.
J Agric Food Chem ; 67(15): 4259-4272, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30913881

RESUMO

Maslinic acid (MA), a natural triterpenoid abundant in olives, has a variety of bioactivities. However, its effects and mechanisms on colorectal cancer (CRC) still need to be explored. This research evaluated the effects of MA on CRC progression from the aspect of the adenosine monophosphate (AMP)-activated protein kinase (AMPK)-mammalian target of rapamycin (mTOR) pathway. MA inhibited the proliferation and migration of HCT116 and SW480 cells while inducing apoptosis in these cells. Furthermore, it could activate AMPK and negatively regulate the mTOR pathway. Knockdown of AMPK abolished its inhibitory effect on cell proliferation and migration and blocked the MA-induced apoptosis, revealing that AMPK was associated with the anticancer activity of MA. In addition, MA significantly suppressed the tumorigenesis and regulated the AMPK-mTOR pathway in azoxymethane/dextran sulfate sodium mice and xenograft tumor mice. This study demonstrated that the regulation of AMPK-mTOR signaling could potentially contribute to the beneficial effects of MA, including the prevention of CRC.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Neoplasias do Colo/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Triterpenos/administração & dosagem , Proteínas Quinases Ativadas por AMP/genética , Animais , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colo/efeitos dos fármacos , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Neoplasias do Colo/fisiopatologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Serina-Treonina Quinases TOR/genética
20.
Planta ; 249(6): 1949-1962, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30895446

RESUMO

MAIN CONCLUSION: Tripsacum dactyloides is closely related to Zea mays since Zea perennis and the MTP tri- species hybrid have four possible reproductive modes. Eastern gamagrass (Tripsacum dactyloides L.) and tetraploid perennial teosinte (Zea perennis) are well known to possess genes conferring resistance against biotic and abiotic stresses as well as adaptation to flood and aluminum toxic soils. However, plant breeders have been hampered to utilize these and other beneficial traits for maize improvement due to sterility in their hybrids. By crossing a tetraploid maize-inbred line × T. dactyloides, a female fertile hybrid was produced that was crossed with Z. perennis to yield a tri-genomic female fertile hybrid, which was backcrossed with diploid maize to produce BC1 and BC2. The tri-genomic hybrid provided a new way to transfer genetic material from both species into maize by utilizing conventional plant breeding methods. On the basis of cytogenetic observations using multi-color genomic in situ hybridization, the progenies were classified into four groups, in which chromosomes could be scaled both up and down with ease to produce material for varying breeding and genetic purposes via apomixis or sexual reproduction. In the present study, pathways were found to recover maize and to obtain specific translocations as well as a speedy recovery of the T. dactyloides-maize addition line in a second backcross generation. However, phenotypes of the recovered maize were in most cases far from maize as a result of genetic load from T. dactyloides and Z. perennis, and could not be directly used as a maize-inbred line but could serve as an intermediate material for maize improvement. A series of hybrids was produced (having varying chromosome number, constitution, and translocations) with agronomic traits from all three parental species. The present study provides an application of overcoming the initial interspecific barriers among these species. Moreover, T. dactyloides is closely related to Z. mays L. ssp. mays since Z. perennis and the MTP tri- species hybrid have four possible reproductive modes.


Assuntos
Cromossomos de Plantas/genética , Fluxo Gênico , Especiação Genética , Genoma de Planta/genética , Poaceae/genética , Zea mays/genética , Apomixia , Quimera , Segregação de Cromossomos , Hibridização In Situ , Fenótipo , Melhoramento Vegetal , Poliploidia , Reprodução , Translocação Genética
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