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1.
Small ; : e2311779, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530085

RESUMO

Micrometer-sized Si particles are beneficial to practical lithium-ion batteries in regard to low cost and high volumetric energy density in comparison with nanostructured Si anodes. However, both the issues of electrical contact loss and overgrowth of solid electrolyte interface for microscale Si induced by colossal volume change still remain to be addressed. Herein, a scalable and template-free method is introduced to fabricate yolk-shell structured Si anode from commercially available Si microparticles. The void is created via a one-step alkali etching process with the remaining silicon core as the yolk, and a double-walled shell is formed from simultaneous in situ growth of the conformal native oxide layer and subsequent carbon coating. In this configuration, the well-defined void spaces allow the Si core to expand without compromising structural integrity, while the double-walled shell acts as a static capsule to confine silicon fragments despite likely particle fracture. Therefore, electrical connectivity is maintained on both the particle and electrode level during deep galvanostatic cycling, and the solid-electrolyte interface is stabilized on the shell surface. Owing to the benefits of tailored design, excellent cycling stability (capacity retention of 95% after 100 cycles) and high coulombic efficiency (99.5%) are realized in a practical full-cell demonstration.

2.
Opt Express ; 32(3): 4603-4613, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297657

RESUMO

The key to uncovering underlying fluid mechanisms lies in high-resolution and large-scale three-dimensional (3D) measurements of flow fields. Currently, the mainstream methods that are capable of volumetric measurements, such as tomographic background oriented schlieren and conventional plenoptic background oriented schlieren (plenoptic BOS), suffer system complexity and low axial resolution, respectively, prohibiting their application in high fidelity 3D flow measurement. This paper proposed an isotropic resolution plenoptic BOS (ISO plenoptic BOS) system that employed a mirror to create a second image view for the region of interest, thereby can achieve isotropic spatial resolution with only one camera. We comprehensively assessed the feasibility of the system by imaging the density field induced by candle flames, heat gun, and the Mach disk produced by the underexpanded jet through the high-pressure nozzle exit. All results proved that the dual-view plenoptic BOS system has higher axial resolution and can provide a more accurate 3D density field than the conventional system. As a BOS system that can achieve high-resolution volumetric imaging without the additional cost of cameras, data acquisition, hardware synchronization, and scanning, our ISO plenoptic BOS can expand the road to large-scale and high-resolution aerodynamic imaging.

3.
ACS Appl Mater Interfaces ; 16(7): 8802-8812, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38319879

RESUMO

Silicon (Si) stands out as a highly promising anode material for next-generation lithium-ion batteries. However, its low intrinsic conductivity and the severe volume changes during the lithiation/delithiation process adversely affect cycling stability and hinder commercial viability. Rational design of electrode architecture to enhance charge transfer and optimize stress distribution of Si is a transformative way to enhance cycling stability, which still remains a great challenge. In this work, we fabricated a stable integrated Si electrode by combining two-dimensional graphene sheets (G), one-dimensional Si nanowires (SiNW), and carbon nanotubes (CNT) through the cyclization process of polyacrylonitrile (PAN). The integrated electrode features a G/SiNW framework enveloped by a conformal coating consisting of cyclized PAN (cPAN) and CNT. This configuration establishes interconnected electron and lithium-ion transport channels, coupled with a rigid-flexible encapsulated coating, ensuring both high conductivity and resistance against the substantial volume changes in the electrode. The unique multidimensional structural design enhances the rate performance, cyclability, and structural stability of the integrated electrode, yielding a gravimetric capacity (based on the total mass of the electrode) of 650 mAh g-1 after 1000 cycles at 3.0 A g-1. When paired with a commercial LiNi0.5Co0.2Mn0.3O2 cathode, the resulting full cell retains 84.8% of its capacity after 160 cycles at 2.0 C and achieves an impressive energy density of 435 Wh kg-1 at 0.5 C, indicating significant potential for practical applications. This study offers valuable insights into comprehensive electrode structure design at the electrode level for Si-based materials.

4.
BMC Cancer ; 24(1): 133, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273249

RESUMO

PURPOSE: There are limited and no standard therapies for recurrent glioblastoma. We herein report the antitumour activity and safety of sintilimab, bevacizumab and temozolomide (TMZ) in recurrent glioblastoma. METHODS: We retrospectively analysed eight patients with recurrent glioblastoma treated with sintilimab (200 mg) every three weeks + bevacizumab (10 mg/kg) every three weeks + TMZ (200 mg/m²orally) (5 days orally every 28 days for a total of four weeks). The primary objective was investigator-assessed median progression-free survival(mPFS). Secondary objectives were to assess the 6-month PFS, objective response rate (ORR) and duration of response (DOR) accroding to RANO criteria. RESULTS: The mPFS time for 8 patients was 3.340 months (95% CI: 2.217-4.463), The longest PFS was close to 9 months. Five patients were assessed to have achieved partial response (PR), with an overall remission rate of 62.5%, Four patients experienced a change in tumour volume at the best response time of greater than 60% shrinkage from baseline, and one patient remained progression free upon review, with a DOR of more than 6.57 months. The 6-month PFS was 25% (95% CI: 5.0-55.0%). Three patients had a treatment-related adverse events, though no grade 4 or 5 adverse events occurred. CONCLUSION: In this small retrospective study, the combination regimen of sintilimab, bevacizumab and TMZ showed promising antitumour activity in treatment of recurrent glioblastoma, with a good objective remission rate.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Bevacizumab/efeitos adversos , Estudos Retrospectivos , Dacarbazina/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia
5.
J Atheroscler Thromb ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38092392

RESUMO

AIMS: Critical limb ischemia (CLI) is an emerging public health threat and lacks a reliable score for predicting the outcomes. The Age, Body Mass Index, Chronic Kidney Disease, Diabetes, and Genotyping (ABCD-GENE) risk score helps identify patients with coronary artery disease who have cytochrome P450 2C19 (CYP2C19) polymorphism-related drug resistance and are at risk for cardiovascular adverse events. However, its application to CLI remains unknown. In this study, we aim to validate a modified ACD-GENE-CLI score to improve the prediction of major adverse limb events (MALEs) in patients with CLI receiving clopidogrel. METHODS: Patients with CLI receiving clopidogrel post-endovascular intervention were enrolled prospectively in two medical centers. Amputation and revascularization as MALEs were regarded as the outcomes. RESULTS: A total of 473 patients were recruited, with a mean follow-up duration of 25 months. Except for obesity, old age, diabetes, chronic kidney disease (CKD), and CYP2C19 polymorphisms were significantly associated with MALEs. Using bootstrap regression analysis, we established a modified risk score (ACD-GENE-CLI) that included old age (≥ 65 years), diabetes, CKD, and CYP2C19 polymorphisms. At a cutoff value of 8, the ACD-GENE-CLI score was superior to the CYP2C19 deficiency only, and the conventional ABCD-GENE score in predicting MALEs (area under the curve: 0.69 vs. 0.59 vs. 0.67, p=0.01). The diagnostic ability of the ACD-GENE-CLI score was consistent in the external validation. Also, Kaplan-Meier curves showed that in CYP2C19 deficiency, the ABCD-GENE and ACD-GENE-CLI scores could all differentiate patients with CLI who are free from MALEs. CONCLUSIONS: The modified ACD-GENE-CLI score could differentiate patients with CLI receiving clopidogrel who are at risk of MALEs. Further studies are required to generalize the utility of the score.

6.
ACS Appl Mater Interfaces ; 14(36): 40975-40984, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36049121

RESUMO

Many challenges still exist in lithium-oxygen batteries (LOBs), particularly exploring an efficient catalyst to optimize the reaction pathway and regulate the Li2O2 nucleation. Pr6O11 has a unique 4f electronic structure and the highest oxygen ion mobility among rare earth oxides, exhibiting superior electronic, optical, and chemical properties. These unique properties might endow it with advanced catalytic activities for LOBs. This work reports two crystal forms of Pr6O11 as novel catalysts and regulates the oxygen vacancy (Vo) concentrations by feasible calcination. Thermogravimetric analysis, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS) confirm the conversion from commercial Pr6O11 to cubic fluorite Pr6O11 and Vo-rich Pr6O11. Photographs, high-resolution transmission electron microscopy, selected area electron diffraction, XPS, and electron paramagnetic resonance robustly demonstrate the temperature-dependent evolution of Vo. Ex situ XPS, scanning electron microscopy, and electrochemical techniques are used to study the catalytic mechanism and electrochemical reversibility. It is found that an appropriate Vo concentration can boost O2 adsorption/desorption, accelerate electron transport, and reduce the reaction energy barrier. Vo-rich Pr6O11 optimizes the reaction pathway by offering an intermediate Li2-xO2 (with metalloid conductivity) and adjusting Li2O2 into vertically staggered nanoflakes, effectively avoiding the suffocation of the catalytic surface and presenting excellent capacity, cycling stability, and rate performance.

7.
Front Chem ; 10: 882681, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464200

RESUMO

Silicon is considered as the most promising candidate for anodes of next generation lithium-ion batteries owing to its natural abundance and low Li-uptake potential. Building a macroporous structure would alleviate the volume variation and particle fracture of silicon anodes during cycling. However, the common approaches to fabricate macroporous silicon are complex, costly, and high energy-consuming. Herein, bamboo leaves are used as a sustainable and abundant resource to produce macroporous silicon via a scalable magnesiothermic reduction method. The obtained silicon inherits the natural interconnected network from the BLs and the mesopores from the BL-derived silica are engineered into macropores by selective etching after magnesiothermic reduction. These unique structural advantages lead to superior electrochemical performance with efficient electron/ion transport and cycling stability. The macroporous Si@C composite anodes deliver a high capacity of 1,247.7 mAh g-1 after 500 cycles at a current density of 1.0 A g-1 with a remarkable capacity retention of 98.8% and average Coulombic efficiency as high as 99.52% for the same cycle period. Furthermore, the rate capabilities of the Si@C composites are enhanced by conformal carbon coating, which enables the anode to deliver a capacity of 538.2 mAh g-1 at a high current density of 4.0 A g-1 after 1,000 deep cycles. Morphology characterization verifies the structural integrity of the macroporous Si@C composite anodes. This work demonstrated herein provides a simple, economical, and scalable route for the industrial production of macroporous Si anode materials utilizing BLs as a sustainable source for high-performance LIBs.

8.
Environ Toxicol ; 37(8): 1853-1866, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35426242

RESUMO

This study researched the function of long non-coding RNA LINC00365 in lung adenocarcinoma (LAD) progression. LINC00365, miR-429, and KCTD12 expression in the LAD clinical tissues and cells were detcetd by qRT-PCR and Western blot. LINC00365, miR-429, and KCTD12 effects on H1975 cells malignant phenotype were detected by cell counting kit-8 assay, clone formation experiment, Transwell experiment, and glycolysis. Dual luciferase reporter gene assay and RNA pull-down assay were implemented. LINC00365 effect on H1975 cells in vivo growth was detected. LINC00365 was low expressed in the LAD patients and cells, associating with poor outcome. LINC00365 up-regulation attenuated H1975 cells proliferation, migration, invasion, glycolysis and in vivo growth. LINC00365 inhibited KCTD12 expression by sponging miR-429. miR-429 up-regulation and KCTD12 down-regulation partial reversed LINC00365 inhibition on H1975 cells malignant phenotype. Thus, LINC00365 inhibited LAD progression and glycolysis via targeting miR-429/KCTD12 axis. LINC00365 might be a potential candidate for LAD target treatment clinically.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Pulmonares , MicroRNAs , RNA Longo não Codificante , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glicólise/genética , Humanos , Neoplasias Pulmonares/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas/genética , Proteínas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
9.
ACS Appl Mater Interfaces ; 13(44): 52519-52529, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34719234

RESUMO

The in situ growth of active materials on 3D current collectors (such as Ni foams) presents facile and efficient access to high-performance supercapacitors. However, the low surface area of current collectors limits the mass loading, microstructure, and capacitive performance of active materials thereon. Herein, we develop a novel surface modification with hierarchical N-rich carbon nanosheets on Ni foams via a simple sol-gel method. At the same time, its favorable effects on mass loading and utilization are demonstrated using NiCoMn-carbonate hydroxide (NCM) as a model active material. Specifically, the carbon modification greatly boosts the current collector's specific surface area and enables the growth of dense NCM nanoneedles with controllable mass loading ranging from 5.2 to 23.1 mg cm-2. Meanwhile, the correlation between mass loading and utilization is systematically studied, which shows the well-maintained energy storage efficiency due to the conducive surface modification. As a result, excellent performance with the ultrahigh area-specific capacity of 19.36 F cm-2 at 2 mA cm-2 in the three-electrode configuration and remarkable area-specific energy density of 1352 µW h cm-2 in the solid-state asymmetric device can be achieved, demonstrating a prospective pathway toward facile and effective current collector designs for high-energy/power-density supercapacitors.

10.
Beilstein J Nanotechnol ; 10: 2207-2216, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31807406

RESUMO

Transition metal compounds such as nickel cobalt sulfides (Ni-Co-S) are promising electrode materials for energy storage devices such as supercapacitors owing to their high electrochemical performance and good electrical conductivity. Developing ultrathin nanostructured materials is critical to achieving high electrochemical performance, because they possess rich active sites for electrochemical reactions, shortening the transport path of ions in the electrolyte during the charge/discharge processes. This paper describes the synthesis of ultrathin (around 10 nm) flower-like Ni1- x Co x S2 nanoflakes by using templated NiCo oxides. The as-prepared Ni1- x Co x S2 material retained the morphology of the initial NiCo oxide material and exhibited a much improved electrochemical performance. The Ni1- x Co x S2 electrode material exhibited a maximum specific capacity of 1066.8 F·g-1 (533.4 C·g-1) at 0.5 A·g-1 and a capacity retention of 63.4% at 20 A·g-1 in an asymmetric supercapacitor (ASC). The ASC showed a superior energy density of 100.5 Wh·kg-1 (at a power density of 1.5 kW·kg-1), an ultrahigh power density of 30 kW·kg-1 (at an energy density of 67.5 Wh·kg-1) and excellent cycling stability. This approach can be a low-cost way to mass-produce high-performance electrode materials for supercapacitors.

11.
Materials (Basel) ; 12(24)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31835409

RESUMO

Nano-sized spinel LiMn2O4/carbon nanotubes (LMO/CNTs) composite is facilely synthesized via a one-step dynamic hydrothermal approach. The characterizations and electrochemical measurements reveal that LiMn2O4 particles with narrow size distribution are well dispersed with CNTs in the composite. The LMO/CNTs nanocomposite with 5 wt % CNTs displays a high specific discharge capacity of 114 mAh g-1 at 1C rate, and the retention rate after 180 cycles at room temperature reaches 94.5% in the potential window of 3.3 to 4.3 V vs. Li/Li+. Furthermore, the electrochemical performance of the composite with 5 wt % CNTs at elevated temperature (55 °C) is also impressive, 90% discharging capacity could be maintained after 100 cycles at 1C. Such excellent electrochemical performance of the final product is attributed to the content of CNTs added in the hydrothermal process and small particle size inherited from pretreated MnO2 precursor.

12.
DNA Cell Biol ; 38(8): 808-813, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31335167

RESUMO

This study aims to investigate whether a relationship exists between the C3435T polymorphism of ABCB1 gene and poststroke depression (PSD). A total of 82 PSD patients and 115 nondepression patient (NPSD) controls were included in this study. All patients were evaluated using the Hamilton Rating Scale for Depression to determine the severity of depression and complete the packet. PSD patients were diagnosed in accordance with the DSM-V criteria. The C3435T polymorphism of ABCB1 was genotyped through fluorescence in situ hybridization and chromosome karyotype analysis system. The PSD (n = 82) and NPSD groups (n = 115) had a total prevalence rate of 41.6%. The prevalence of PSD in men was 58.5%, whereas that in women was 41.5%, and no statistically significant difference existed between the two groups (χ2 = 1.009; p = 0.315). The CC, CT, and TT frequencies of the PSD group were 26.8%, 47.6%, and 25.6%, respectively, whereas those of the NPSD group were 42.6%, 45.2%, and 12.2%, respectively. Based on the CC genotype, the relative risk of homozygous mutant TT was 3.341 (χ2 = 7.869; p = 0.005; OR = 3.341), and the T allele frequency in the PSD group was 49.4% higher than that in the NPSD group. The locus gene frequency was 34.8%, and the relative risk of allele T relative to allele C was 1.830 (χ2 = 8.381; p = 0.004; OR = 1.830). A certain correlation exists between the C3435T gene polymorphism and PSD in the Han population in South Anhui Province, China, and further studies are needed to confirm our findings.


Assuntos
Depressão/genética , Polimorfismo Genético , Acidente Vascular Cerebral/psicologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Povo Asiático/genética , China , Depressão/etiologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações
13.
ChemistryOpen ; 8(3): 298-303, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30886787

RESUMO

In this work, we introduce Ni nanopyramid arrays (NPAs) supported amorphous Ge anode architecture and demonstrate its effective improvement in sodium storage properties. The Ni-Ge NPAs are prepared by facile electrodeposition and sputtering method, which eliminates the need for any binder or conductive additive when used as a Na-ion battery anode. The electrodes display stable cycling performance and enhanced rate capabilities in contrast with planar Ge electrodes, which can be owing to the rational design of the architectured electrodes and firm bonding between current collector and active material (i. e. Ni and Ge, respectively). To validate improvement of nanostructures on electrochemical performance, sodium insertion behavior of crystalline Ge derived from Mg2Ge precursor has been investigated, in which limited but effective enhancement of sodium storage properties are realized by introducing porous nanostructure in crystalline Ge. These results show that elaborately designed configuration of Ge electrodes may be a promising anode for Na-ion battery applications.

14.
Thorac Cancer ; 8(1): 46-50, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27910227

RESUMO

BACKGROUND: The non-recurrent laryngeal nerve (NRLN) is a rare but potentially serious anomaly that is commonly associated with the aberrant right subclavian artery (ARSA). It is easy to damage during surgical resection of esophageal cancer, leading to severe complications. METHODS: Preoperative enhanced thoracic computed tomography (CT) scans of 2697 patients with esophageal carcinoma treated in our hospital between January 2010 and December 2013 were examined. We classified the positional relationship between the right subclavian artery and the membranous wall of the trachea into two types and used this method to predicate NRLN by identifying ARSA. RESULTS: Twenty-six patients (0.96%) were identified with ARSA, all of which were cases of NRLN by CT. NRLN was identified during surgery in the 26 patients, and a normal right recurrent laryngeal nerve was observed in 2671 patients. The ARSA was detected on the dorsal side of the membranous wall of the trachea in all 26 NRLN cases, while it was detected on the ventral side in all 2671 recurrent laryngeal nerve cases. CONCLUSION: Enhanced CT scanning is a reliable method for predicting NRLN by identifying ARSA. Preoperative recognition of this nerve anomaly allows surgeons to avoid damaging the nerve and abnormal vessels during esophagectomy.


Assuntos
Aneurisma/diagnóstico por imagem , Anormalidades Cardiovasculares/diagnóstico por imagem , Doenças dos Nervos Cranianos/diagnóstico por imagem , Transtornos de Deglutição/diagnóstico por imagem , Neoplasias Esofágicas/cirurgia , Nervo Laríngeo Recorrente/anormalidades , Artéria Subclávia/anormalidades , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Neoplasias Esofágicas/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Estudos Retrospectivos , Artéria Subclávia/diagnóstico por imagem
15.
ACS Appl Mater Interfaces ; 8(51): 35172-35179, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27959502

RESUMO

The challenging problems of SnO2 anode material for lithium ion batteries are the poor electronic conductivity and the low oxygen reutilization due to the irreversibility of Li2O generated in the initial discharge leading to a theoretical initial Coulombic efficiency (ICE) of only 52.4%. Different from these strategies, this work proposes a novel strategy to level up the oxygen reutilization in SnO2 by introducing Co3Sn2 nanoalloys which can release Co atoms to reversibly react with Li2O instead. According to this protocol, multi-yolk-shell SnO2/Co3Sn2@C nanocubes are designed and successfully prepared using hollow CoSn(OH)6 nanocubes as precursors followed a hydrothermal carbon coating and calcination treatment. The unique multi-yolk-shell nanostructure offers adequate breathing space for the volumetric deformation during long-term cycling. Moreover, the removal of Li2O allows a high electronic conductivity and resultant rate performance. As a result, the efficient reutilization of oxygen enables a high ICE of 71.7% and a reversible capacity of 1003 mA h g-1 after 200 cycles at 100 mA g-1. Cyclic voltammetry, cycling performance at different voltage windows, and X-ray photoelectron spectroscopy confirm the proposed mechanism. This strategy employing oxygen-poor metals or alloys provides a novel approach to enhance the oxygen reutilization in SnO2 for higher reversibility.

16.
BMC Evol Biol ; 16: 73, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27068356

RESUMO

BACKGROUND: The South China landmass has been characterized by a complex geological history, including mountain lifting, climate changes, and river capture/reversal events. To determine how this complexity has influenced the landmass's phylogeography, our study examined the phylogeography of Garra orientalis, a cyprinid widely distributed in South China, using sequences from the mitochondrial DNA control region and cytochrome b gene (1887 bp) and polymorphisms of thirteen microsatellite loci. RESULTS: In total, 157 specimens were collected from eight populations. All 88 mtDNA haplotypes were identified as belonging to three major lineages, and these lineages were almost allopatric in their distributions. The results of a statistical dispersal-vicariance analysis suggested that the ancestral populations of G. orientalis were distributed south of the Yunkai Mountains, including on Hainan Island. The mtDNA data revealed a strong relationship between phylogeny and geography. In the microsatellite analysis, a total of 339 alleles with an average of 26 alleles per locus were observed across thirteen microsatellite loci. A clustering algorithm for microsatellite data revealed an admixture-like genetic structure. Although the mtDNA and microsatellite data sets displayed a discordant population structure, the results of an approximate Bayesian computation approach showed that these two markers revealed congruent historical signals. The population history of G. orientalis reflects vicariance events and dispersal related to the complex geological history of South China. CONCLUSION: Our results (i) found that the discordances between mtDNA and microsatellite markers were accounted for by admixtures; (ii) showed that the Wuzhishan and Yinggeling mountain ranges and Qiongzhou Strait were important barriers limiting gene exchange between populations on both sides; (iii) indicated that during glaciation and inter-glacial periods, the strait and continental shelves were exposed and sank, which contributed with the dispersion and differentiation of populations; and (iv) displayed that the admixtures between lineages took place in coastal populations and then colonized the tributaries of the Pearl River.


Assuntos
Cyprinidae/genética , Animais , Teorema de Bayes , China , Citocromos b/genética , DNA Mitocondrial/genética , Genética Populacional , Repetições de Microssatélites , Dados de Sequência Molecular , Filogenia , Filogeografia , Polimorfismo Genético
17.
Ying Yong Sheng Tai Xue Bao ; 26(6): 1759-64, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26572029

RESUMO

In this paper, the spring wheat (cv. Xihan No. 2) was taken as research material to investigate the dynamic changes of the non-structural carbohydrates (NSC) in flag leaves, stems and leaf sheaths and activities of carbon-metabolizing enzymes (SSS, GBSS) in grains during wheat development process under various water stresses by water stress and re-watering treatment methods. The results indicated that various water stresses had no significant effects on the sucrose contents in flag leaves, stems, leaf sheaths and other organs of wheat. With the increase of water stress, the content of starch in flag leaves was significantly increased within 12-18 d after flowering. Water stress shortened the starch accumulation period in stems and sheaths after flowering and inhibited the transformation and distribution of starch in wheat stems. The accumulation of starch in sheath also gradually increased, which was early terminated under moderate water stress. At the beginning of the water stress, the contents of NSC in vegetative organs were listed as: flag leaves > stems > leaf sheaths. With the increase of water stresses, the NSC contents in vegetative organs were listed as: stems > flag leaves > leaf sheaths. We could conclude that the changes in main NSC (sugar, starch) distribution and carbon-metabolism enzyme activities was a kind of physiological regulation response of wheat to water stresses.


Assuntos
Desidratação , Amido/química , Estresse Fisiológico , Triticum/fisiologia , Água/química , Carbono/química , Folhas de Planta/química , Sacarose/química
18.
Phys Chem Chem Phys ; 17(27): 17562-5, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26082288

RESUMO

Yolk-shell Si@void@C nanocomposites are prepared via a facile method of resorcinol-formaldehyde coating and LiOH etching, without SiO2 pre-modification on Si particles, expensive carbon sources, or environmentally-unfriendly HF solutions. Profiting from these favorable features, Si@void@C nanocomposites exhibit considerable reversible capacities (628 mA h g(-1) after 100 cycles) and good rate performances.

19.
Biochem Biophys Res Commun ; 457(4): 572-7, 2015 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-25603047

RESUMO

In the past decade, monoclonal antibodies (mAbs) have revolutionized the treatment of non-Hodgkin lymphomas (NHLs). Although Fc-dependent mechanisms of mAb-mediated tumor clearance have been extensively studied, the ability of mAbs to directly evoke programmed cell death (PCD) and the underlying mechanisms involved remain unclear. It is well established that type II anti-CD20 mAb (Tositumomab) potently evoked PCD through a caspases-independent, lysosome-mediated process, which is related to homotypic adhesion (HA) in NHL cell lines. Herein, we reveal that the induction of ceramide generation by anti-CD20 mAbs directly correlates with their ability to induce PCD. The inhibition of ceramide abrogated Tositumomab-induced PCD indicating that ceramide is required for the execution of cell death. Further experimental results revealed that ceramide was generated downstream of mAb-induced HA and upstream of lysosome leakage. These findings provide further insights into a previously unrecognized role for ceramide generation in mediating PCD evoked by type II anti-CD20 mAbs in Burkitt's lymphoma cells. This newly characterized cell death pathway may potentially be exploited to eliminate malignant cells.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD20/imunologia , Antineoplásicos/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Ceramidas/imunologia , Lisossomos/efeitos dos fármacos , Anticorpos Monoclonais/imunologia , Antineoplásicos/imunologia , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/patologia , Caspases/imunologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Lisossomos/imunologia , Lisossomos/patologia , Transdução de Sinais/efeitos dos fármacos
20.
Mitochondrial DNA ; 26(2): 272-3, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24021003

RESUMO

The oriental sucking barb, Garra orientalis, is a small to moderate-sized freshwater fish. In this study, the complete mitochondrial genome of G. oriental was successfully sequenced for the first time with total length of 17,288 bp. The genome structure consists of 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA (tRNA) genes and a control region. Moreover, tandem repeat unit ranged from 259 to 260 bp (repeated 3-4 times) was identified in the control region among G. orientalis individuals.


Assuntos
Cyprinidae/genética , Genoma Mitocondrial , Animais , Composição de Bases , Genes Mitocondriais , Fases de Leitura Aberta , Sequências Reguladoras de Ácido Nucleico , Sequências Repetitivas de Ácido Nucleico
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