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1.
Onco Targets Ther ; 13: 11125-11137, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149623

RESUMO

Background: Alterations in the cell metabolism, such as enhanced aerobic glycolysis, have been identified as a prominent hallmark of cancer cells. 3-Bromopyruvate (3-BrPA) is a proverbial hexokinase (HK)-II inhibitor, which can inhibit cancer cell energy metabolism. Rapamycin is a new type macrocyclic lactone, which can inhibit the serine/threonine protein kinase mTOR. In order to comprehend the influence of 3-BrPA on autophagy activity in vitro, we conducted a series of experiments using different human neuroblastoma (NB) cell lines. Materials and Methods: The human NB cell lines were exposed to 3-BrPA and/or rapamycin, and the proliferation activity of the cells was detected by Cell Counting Kit-8 (CCK-8) assay. The mRNA expression of the cells treated with 3-BrPA and/or rapamycin was analyzed by quantitative real-time polymerase chain reaction (QPCR) assay. The protein expression of the cells was analyzed by Western Blotting (WB) assay. The effects of 3-BrPA and/or rapamycin treatment on cell cycle and cell apoptosis were analyzed by flow cytometry assay. Meanwhile, the cellular glucose absorption rate, lactate secretion rate and ATP content were also analyzed through the relevant metabolic analysis kits. Results: Our results showed that 3-BrPA can induce growth inhibition in a dose-dependent pattern by cell apoptosis. 3-BrPA combined with rapamycin played a synergistic suppression role in NB cells, affected the cell apoptosis, cell cycle and the metabolic pathway. Up-regulated LC3-II accumulation was conscious in NB cells incubated with 3-BrPA and rapamycin. Rapamycin individually discourages the mTOR signaling pathway, while combined with 3-BrPA can enhance this phenomenon and influence cell metabolism of the NB cells. Conclusion: The results suggested that 3-BrPA combined with rapamycin could induce cell apoptosis in NB cells by inhibiting mTOR activity. In conclusion, our research proposed that the dual inhibitory effect of the mTOR signaling pathway and the glycolytic activity may indicate a valid therapeutic tactic for NB chemoprevention.

2.
Curr Neurovasc Res ; 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32875986

RESUMO

OBJECTIVE: To explore the changes of FA values in the diffusion tensor imaging (DTI) of patients with mild cognitive impairment in Parkinson's disease (PD). METHODS: 27 patients with PD were divided into PD with mild cognitive impairment (PD-MCI) group (n=7) and PD group (n=20). The original images were processed using voxel-based analysis (VBS) and area-based spatial statistics (TBSS). RESULTS: The mean age of onset in the PD-MCI group was greater than that in PD group, and the course of disease course was longer than that in the PD group. Compared with PD group, voxel based analysis-fractional anisotropy (VBA-FA) values in PD-MCI group decreased in the following areas: bilateral frontal lobe, bilateral temporal lobe, bilateral parietal lobe, bilateral subthalamic nucleus, corpus callosum and gyrus cingula tract-based spatial statistics-fractional anisotropy (TBSSFA) values in PD-MCI group decreased in bilateral corticospinal tract, anterior cingulum, posterior cingulum, fornix tract, bilateral superior thalamic radiation, corpus callosum(genu, body and splenium), bilateral uncinate fasciculus, bilateral inferior longitudinal fasciculus, bilateral superior longitudinal fasciculus, bilateral superior fronto-occipital fasciculus, bilateral inferior fronto-occipital fasciculus and bilateral parietal-occipital tracts. The mean age of onset in the PD-MCI group was greater than that in the PD group, and the disease course was longer than that in the PD group. CONCLUSION: DTI-based VBA and TBSS post-processing methods can detect abnormalities in multiple brain areas and white matter fiber tracts in PD-MCI patients. Impairment of multiple cerebral cortex and white matter fiber pathways may be important causes of cognitive dysfunction in PD-MCI.

3.
Inorg Chem ; 59(17): 12445-12452, 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32805988

RESUMO

A new oxide, LaMn3Co2Mn2O12, was synthesized under high-pressure (7 GPa) and high-temperature (1423 K) conditions. The compound crystallizes in an AA'3B4O12-type quadruple perovskite structure with space group Im3̅. The Rietveld structural analysis combined with soft X-ray absorption spectroscopy reveals the charge combination to be LaMn3+3Co2+2Mn4+2O12, where the La3+ and Mn3+ are 1:3 ordered respectively at the A and A' sites, whereas the Co2+ and Mn4+ are disorderly distributed at the B site. This is in sharp contrast to R2Co2+Mn4+O6 (R = La and rare earth) double perovskites, in which the Co2+ and Mn4+ charge states are always orderly distributed with a rocksalt-type fashion, giving rise to a long-range magnetic ordering. As a result, LaMn3Co2Mn2O12 displays spin glassy magnetic properties due to the random Co2+ and Mn4+ distribution, as demonstrated by dc and ac magnetic susceptibility as well as specific heat measurements. Possible factors that affect the B-site degree of order in perovskite structures are discussed.

4.
Theriogenology ; 156: 222-235, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32768871

RESUMO

Laying fatigue syndrome (LFS) is a common disease in poultry, which is characterized by low egg laying rate, increased broken and soft shell egg rate and osteoporosis, and even death of poultry. Insufficient phosphorus content in feed is one of the major causes of LFS. In this study, a total of 22-week-old Roman white shell hens were randomly divided into two groups, including control (group C) and low dietary phosphorus (group P) groups. The hens of groups C and P were fed with a full mixed diet and a mixed diet containing 0.18% available phosphorus content, respectively. At 25, 29 and 34 weeks, the production performance of hens was detected and the serum samples of hens were collected to detect the changes of serum phosphorus, calcium, osteopelectin (OPG), parathyroid hormone (PTH), estradiol (E2), tartaric acid-resistant phosphatase (TRACP) and alkaline phosphatase (ALP). The keels were removed and x-rayed. In addition, all serum samples were tested by LC-MS metabolomics. Our results showed that low dietary phosphorus decreased the production performance, phosphorus content, and E2 and OPG levels, while increased calcium and PTH levels, and ALP and TRACP activities in laying hens. The hens of group P had bent keels. Besides, small molecular metabolites in serum were enriched in 10 pathways and 17 metabolites were significantly different according to the area under the receiver operating characteristic curve (AUC) analysis. Our results showed that low phosphorus diet could induce LFS. Also, 17 metabolites detected by metabonomics can be used as biomarkers for clinical diagnosis and early warning of hypophosphatemic laying fatigue syndrome (HLFS). This study provides a scientific basis for the early prevention and treatment of HLFS.

5.
Int J Syst Evol Microbiol ; 70(8): 4531-4536, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32614764

RESUMO

A Gram-staining-negative bacterium, designated 345S023T, was isolated from a sea water sample from the Indian Ocean. The results of 16S rRNA gene sequence analysis revealed that 345S023T represents a member of the genus Alteromonas, with closely related type strains Alteromonas fortis 1T (98.7 %), Alteromonas hispanica F-32T (98.6 %) and Alteromonas genovensis LMG 24078T (98.6 %). Up-to-date bacterial core gene set analysis revealed that 345S023T formed a phyletic lineage with Alteromonas australica H 17T. The case for 345S023T representing a novel species was supported by genomic results. Pairwise in silico DNA-DNA hybridization and average nucleotide identity values were much lower than the proposed and generally accepted species boundaries. Strain 345S023T contains ubiquinone-8 (Q-8) as the sole isoprenoid quinone, summed featured 3 (C16 : 1ω7c and/or C16 : 1ω6c), C16 : 0 and C18 : 1ω7c as the dominant cellular fatty acids (>10 %), and phosphatidylglycerol and phosphatidylethanolamine as the major polar lipids. The genome of strain 345S023T consisted of a 4.4 Mb chromosome with a DNA G+C content of 44.4 %. On the basis of these genomic, chemotaxonomic and phenotypic characteristics, we propose a novel species: Alteromonas profundi sp. nov. The type strain is 345S023T(=JCM 33893T=MCCC 1K04570T).


Assuntos
Alteromonas/classificação , Filogenia , Água do Mar/microbiologia , Alteromonas/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
6.
Int J Syst Evol Microbiol ; 70(6): 3839-3844, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32496184

RESUMO

A Gram-stain-negative bacterium, designated strain 501str8T, was isolated from a sediment sample collected from the East Pacific Ocean. 16S rRNA gene sequence analysis revealed that strain 501str8T belonged to the genus Muricauda, with closely related type strains Muricauda aquimarina SW-63T (98.5 %), Muricauda lutimaris SMK-108T (98.3 %) and Muricauda ruestringensis B1T (97.9 %). Up-to-date bacterial core gene set analysis revealed that strain 501str8T represented one independent lineage with M. aquimarina SW-63T. The average nucleotide identity values of strain 501str8T with M. aquimarina SW-63T and M. lutimaris SMK-108T were 80.2 and 81.3 %, respectively. In silico DNA-DNA hybridization values between strain 501str8T and M. aquimarina SW-63T and M. lutimaris SMK-108T were 22.8 and 32.9 %, respectively. The predominant isoprenoid quinone was menaquinone-6, and iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G were the dominant cellular fatty acids. The G+C content of the genomic DNA was 42.8 mol%. Differential phylogenetic distinctiveness and chemotaxonomic differences, together with the phenotypic properties observed in this study, revealed that strain 501str8T could be differentiated from closely related species. Therefore, we propose that strain 501str8T represents a novel species of the genus Muricauda, for which the name Muricauda oceani sp. nov. is suggested. The type strain is 501str8T (=JCM 33902T=MCCC 1K04567T).


Assuntos
Flavobacteriaceae/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Flavobacteriaceae/isolamento & purificação , Hibridização de Ácido Nucleico , Oceano Pacífico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
Int J Syst Evol Microbiol ; 70(7): 4345-4350, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32584750

RESUMO

A Gram-stain-negative bacterium, designated strain 40Bstr34T, isolated from a sediment sample from the West Pacific Ocean, was taxonomically characterized by using a polyphasic approach. The strain was phylogenetically close to Jiella aquimaris LZB041T and Jiella endophytica CBS5Q-3T, with 16S rRNA gene sequence similarities of 98.5 and 97.1 %, respectively. The genome of strain 40Bstr34T featured a G+C content of 65.7 % for a 5.8 Mb chromosome. Up-to-date bacterial core gene set analysis revealed that strain 40Bstr34T represents one independent lineage with J.aquimaris LZB041T. In silico DNA-DNA hybridization values between strain 40Bstr34T and its phylogenetic neighbours ranged from 30.3-34.2 %, below the cutoff of 70 %. In addition, the corresponding average nucleotide identity values were between 81.8-83.7 %, which are lower than 95 % threshold. The predominant cellular fatty acids of strain 40Bstr34T were summed feature 8 (C18 : 1 ω6c and/or C18 : 1 ω7c), cyclo-C19 : 0 ω8c and iso-C17 : 0 3-OH, and ubiquinone-10 as the predominant respiratory quinone. The major polar lipids included phosphatidylethanolamine, phosphatidylmonomethylethanolamine, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylcholine, two unidentified aminolipids and two unidentified lipids. Based on the results of phenotypic, chemotaxonomic and genetic analyses, strain 40Bstr34T is identified as representing a novel species of the genus Jiella for which the name Jiella pacifica sp. nov. is proposed. The type strain is 40Bstr34T (=JCM 33903T=MCCC 1K04569T).


Assuntos
Alphaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Filogenia , Água do Mar/microbiologia , Alphaproteobacteria/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Oceano Pacífico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/análogos & derivados , Ubiquinona/química
8.
Sensors (Basel) ; 19(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013782

RESUMO

Based on a bio-heuristic algorithm, this paper proposes a novel path planner called obstacle avoidance beetle antennae search (OABAS) algorithm, which is applied to the global path planning of unmanned aerial vehicles (UAVs). Compared with the previous bio-heuristic algorithms, the algorithm proposed in this paper has advantages of a wide search range and breakneck search speed, which resolves the contradictory requirements of the high computational complexity of the bio-heuristic algorithm and real-time path planning of UAVs. Besides, the constraints used by the proposed algorithm satisfy various characteristics of the path, such as shorter path length, maximum allowed turning angle, and obstacle avoidance. Ignoring the z-axis optimization by combining with the minimum threat surface (MTS), the resultant path meets the requirements of efficiency and safety. The effectiveness of the algorithm is substantiated by applying the proposed path planning algorithm on the UAVs. Moreover, comparisons with other existing algorithms further demonstrate the superiority of the proposed OABAS algorithm.

9.
J Cell Biochem ; 120(8): 12247-12258, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30864186

RESUMO

Gastric cancer is one of the top causes of cancer-related death around the world, and poor prognosis of gastric cancer is due to the lack of early detection and effective treatment especially in male. Here, we first revealed the role of histone lysine-specific demethylase 5D (KDM5D) in gastric cancer in male. KDM5D was associated with the metastasis of gastric cancer because of its critical role in the epithelial-mesenchymal transition of gastric cancer cells. Downregulation of KDM5D in gastric cancer cells significantly increase the number of migrated or invaded cells due to the increasing expressions of mesenchymal markers. Downregulation of KDM5D also promotes tumor formation of gastric cancer cell in vivo. For mechanism, downregulation of KDM5D could inhibit the demethylation in the promoter of CUL4A, which lead to the increasing expression of ZEB1 and decreasing expressions of p21 and p53. Collectively, KDM5D performed its role in metastasis of gastric cancer through demethylation in the promoter of CUL4A, and it suggested us a novel target in gastric cancer treatment in male.


Assuntos
Proteínas Culina/genética , Desmetilação , Transição Epitelial-Mesenquimal/genética , Histona Desmetilases/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Regiões Promotoras Genéticas , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Animais , Movimento Celular/genética , Proteínas Culina/metabolismo , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica
10.
Inorg Chem ; 58(1): 320-326, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30525537

RESUMO

A new oxide NaCu3Fe2Os2O12 is synthesized using high pressure and temperature conditions. The Rietveld structural analysis shows that the compound possesses both A- and B-site ordered quadruple perovskite structure in Pn3̅ symmetry. The valence states of transition metals are confirmed to be Cu2+/Fe3+/Os5.5+. The three transition metals all take part in magnetic interactions and generate strong Cu2+(↑)Fe3+(↑)Os5.5+(↓) ferrimagnetic superexchange interactions with a high Curie temperature about 380 K. Electrical transport measurements suggest its half-metallic properties. The first-principles theoretical calculations demonstrate that the compound has a spin-down conducting band and a spin-up insulating band with a wide energy gap.

11.
Org Lett ; 20(12): 3700-3704, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29874079

RESUMO

A catalytic highly regioselective, diastereoselective, and enantioselective cyclopropanation of electron-deficient dienes and bromides via direct sulfide organocatalysis is reported. A variety of vinylcyclopropanes featuring a quaternary chiral center were synthesized in up to 99% yield and up to 98:2 enantiomeric ratio (er). These products could be facilely transformed to various interesting molecules with great structural diversity.

12.
Oncol Lett ; 16(1): 267-275, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29928411

RESUMO

Jumonji AT-rich interactive domain 1B (JARID1B) has been revealed to remove methyl residues from methylated lysine 4 on histone H3 (H3K4) and has also been reported to be associated with the progression of numerous types of tumor. However, its roles and mechanisms in pancreatic cancer (PC) remain unknown. The present study demonstrated that JARID1B is elevated in PC and is associated with the growth of pancreatic tumors. Overexpression of JARID1B significantly promoted the proliferation in vitro and tumor formation in vivo of PC cells. Furthermore, silencing the expression of JARID1B in other PC cells revealed opposite effects. Further research revealed that JARID1B exerted its function through modulation of H3K4me3 at the phosphatase and tensin homolog (PTEN) gene promoter which was associated with inactive PTEN transcription. To the best of our knowledge, the present study was the first to demonstrate that JARID1B promotes the growth of PC and that targeting JARID1B may be a useful strategy to suppress the progression of PC.

13.
Inorg Chem ; 57(11): 6716-6721, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29767517

RESUMO

A new TeZnO3 phase was synthesized by high-pressure techniques. Different from the ambient-pressure orthorhombic phase composed of ZnO5 units, the current high-pressure one crystallizes to a monoclinic structure with space group P21/ n. Moreover, both ZnO4 tetrahedral and ZnO6 octahedral polyhedra are found to occur in this new phase, providing a unique Zn-based material system that simultaneously possesses two distinct coordinated units. Because the outermost orbitals are fully occupied for both Zn2+ and Te4+, the compound exhibits diamagnetism and strong insulating behavior with a wide bandgap as large as 6.0 eV. Dielectric constant and specific heat measurements show a broad anomaly around 240 K. Low-temperature synchrotron X-ray diffraction reveals an isostructural phase transition at this temperature.

14.
Int J Syst Evol Microbiol ; 68(5): 1672-1677, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29616891

RESUMO

A novel, alkaliphilic, psychrotolerant, facultative anaerobe, designated CP1T, was isolated from sandy soil near the Davis Station in Antarctica. The short-rod-shaped cells displayed Gram-positive staining and did not form spores. Strain CP1T was able to grow at temperatures between 4 and 36 °C, pH 6.0-9.5, and in the presence of up to 5.0 % (w/v) NaCl. 16S rRNA gene and multilocus (pheS, rpoA, and atpA) sequence analysis revealed Carnobacterium mobile DSM 4848T and Carnobacterium iners LMG 26642T as the closest relatives (97.4 and 97.1 % 16S rRNA gene sequence similarity, respectively). The genomic G+C content was 38.1 mol%, and DNA-DNA hybridization with DSM 4848T revealed 32.4±3.4 % similarity. The major fatty acid components were C14 : 0 and C16 : 1ω9c. The cell wall contained meso-diaminopimelic acid and was of peptidoglycan type A1γ. Based on physiological, genotypic and biochemical characteristics, strain CP1T represents a novel species of the genus Carnobacterium for which the name Carnobacterium antarcticum sp. nov. is proposed. The type strain is CP1T (=DSM 103363T=CGMCC 1.15643T).


Assuntos
Carnobacterium/classificação , Filogenia , Microbiologia do Solo , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Carnobacterium/genética , Carnobacterium/isolamento & purificação , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Quant Imaging Med Surg ; 8(10): 1039-1051, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30598881

RESUMO

Cerebrovascular complications may occur in infectious diseases in the setting of infective endocarditis, central nervous system (CNS) infections, systemic bacteremia and sepsis. Cerebrovascular complications of infections include vasculitis, mycotic aneurysms, and thrombophlebitis. Infectious vasculitis of the CNS may cause cerebral hemorrhage, infarction or ischemia. Ruptured aneurysms may endanger the patient's life. Infectious thrombophlebitis may cause intracranial pressure to increase and lead to cerebral hemorrhage. These cerebrovascular complications are associated with a poor prognosis and often cause irreversible neurological deficits. Cerebrovascular events secondary to infection are not easily distinguishable from the more common cerebral infarct and non-infectious vasculitis. In addition, the clinical manifestations of cerebrovascular complications of infections are non-specific and highly variable. Therefore, early imaging, antibiotics, and anticoagulation may be lifesaving the patient's life and prevent disability. The main focus of this article is to review imaging analysis of the cerebrovascular complications of infections and imaging features that help differentiate them from non-infectious vascular diseases.

16.
Angew Chem Int Ed Engl ; 57(7): 1913-1917, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29276812

RESUMO

Asymmetric construction of halogenated quaternary carbon centers under mild reaction conditions remains challenging. Reported here is an unprecedented and highly stereoselective Brønsted base catalyzed [4+2] cycloaddition between either α-chloro- or α-bromoaldehydes and cyclic enones. The key intermediate, an α-halogenated enolate, is susceptible to dehalogenation and can be stabilized and stereochemically controlled using bifunctional tertiary amines. This method provides facile access to a collection of optically pure bicyclic dihydropyrans having three contiguous stereocenters, including a halogen-bearing quaternary carbon center. Of note, the product can be transformed in situ into densely functionalized spirocyclopropanes in a highly efficient and stereoselective manner.

17.
Adv Mater ; 29(44)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28991383

RESUMO

Magnetoelectric multiferroics have received much attention in the past decade due to their interesting physics and promising multifunctional performance. For practical applications, simultaneous large ferroelectric polarization and strong magnetoelectric coupling are preferred. However, these two properties have not been found to be compatible in the single-phase multiferroic materials discovered as yet. Here, it is shown that superior multiferroic properties exist in the A-site ordered perovskite BiMn3 Cr4 O12 synthesized under high-pressure and high-temperature conditions. The compound experiences a ferroelectric phase transition ascribed to the 6s2 lone-pair effects of Bi3+ at around 135 K, and a long-range antiferromagnetic order related to the Cr3+ spins around 125 K, leading to the presence of a type-I multiferroic phase with huge electric polarization. On further cooling to 48 K, a type-II multiferroic phase induced by the special spin structure composed of both Mn- and Cr-sublattices emerges, accompanied by considerable magnetoelectric coupling. BiMn3 Cr4 O12 thus provides a rare example of joint multiferroicity, where two different types of multiferroic phases develop subsequently so that both large polarization and significant magnetoelectric effect are achieved in a single-phase multiferroic material.

18.
PLoS One ; 12(8): e0182795, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28829841

RESUMO

BACKGROUND AND PURPOSE: Brain tumors in the corticospinal tract (CST) region are more likely to cause motor dysfunction. The aim of this study is to evaluate the effect of gliomas located in the CST region on motor function with diffusion tensor imaging (DTI) preoperatively. MATERIALS AND METHODS: Forty-five patients with histopathologically confirmed gliomas were included in this pilot study, in all cases (low-grade n = 13, high-grade n = 32) CST but not the motor cortex were involved by the tumor. DTI image were acquired and the posterior limb of the internal capsule fractional anisotropy (FA) and relative FA (rFA = affected FA/contralateral FA) were measured. Injury of the CST from tumor was divided into three grades (grade 1: displacement, grade 2: displacement and infiltration, grade 3: displacement and disruption). The fiber density index (FDi) and relative FDi (rFDi = affected FDi/contralateral FDi) of the injured and contralateral CST were measured. The correlations between muscle strength and the CST injury grade and the rFA, affected FDi, rFDi values were calculated using Spearman rank correlation analysis. rFA and rFDi values of muscle strength groups (MMT2-5) were compared with one-way analysis of variance (ANOVA). The difference of muscle strength between low- and high-grade glioma groups were analysed with the Mann-Whitney U-test. RESULTS: Muscle strength was negatively correlated with the injury grade of the CST (r = -0.840, P<0.001). Muscle strength was positively correlated with rFA, FDi and rFDi (correlation coefficients (r) were 0.615, 0.643 and 0.567 for rFA, FDi and rFDi, respectively). The rFA values between grades (2&3, 2&4, 2&5, 3&5, 4&5) of muscle strength were significantly different (P<0.05), the rFDi values between grades (2&4, 2&5, 3&4, 3&5) of muscle strength were significantly different (P<0.05), while the rFA and rFDi values in the remaining groups of muscle strength grades showed no significant differences(P>0.05). CONCLUSIONS: Preoperative DTI and diffusion tensor tractography may quantify the injury degrees of CST and the extent of motor dysfunction in patients with brain glioma.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Imagem de Tensor de Difusão/métodos , Glioma/fisiopatologia , Desempenho Psicomotor , Humanos , Projetos Piloto
19.
Chem Commun (Camb) ; 53(51): 6875-6878, 2017 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-28604911

RESUMO

Highly diastereo and enantioselective [4+2] cycloadditions have been achieved between pyrrolidone-derived cyclic enones and α-haloaldehydes under mild conditions. Relying on extremely reactive in-situ generated chiral N-heterocyclic carbenes, this stereoselective annulation proceeds efficiently even on the gram scale with the catalyst loading as low as 0.025 mol% (250 ppm). A variety of cis-substituted bicyclic dihydropyranones can be produced in up to 96% yield with up to >99% ee. In addition, simple, inexpensive linear aldehydes such as n-propanal can be used directly in asymmetric cycloadditions via oxidative N-heterocyclic carbene organocatalysis with low catalyst loading. This method may provide an economical and practical approach for the asymmetric synthesis of medicinally relevant molecules.

20.
Molecules ; 22(2)2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28241452

RESUMO

A highly diastereoselective cyclopropanation of cyclic enones with sulfur ylides was developed under catalyst-free conditions, producing multifunctional spirocyclopropanes in generally excellent yields (up to 99% yield and >99:1 d.r.). The asymmetric version of this method was realized by using an easily available chiral sulfur ylide, affording products with moderate to good stereoselectivity.


Assuntos
Compostos de Benzilideno/química , Reação de Cicloadição , Ciclopropanos/síntese química , Pirrolidinas/química , Compostos de Espiro/síntese química , Catálise , Ciclopropanos/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Compostos de Espiro/química , Enxofre/química
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