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1.
Nano Lett ; 24(22): 6585-6591, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38785400

RESUMO

The gallium-doped hafnium oxide (Ga-HfO2) films with different Ga doping concentrations were prepared by adjusting the HfO2/Ga2O3 atomic layer deposition cycle ratio for high-speed and low-voltage operation in HfO2-based ferroelectric memory. The Ga-HfO2 ferroelectric films reveal a finely modulated coercive field (Ec) from 1.1 (HfO2/Ga2O3 = 32:1) to an exceptionally low 0.6 MV/cm (HfO2/Ga2O3 = 11:1). This modulation arises from the competition between domain nucleation and propagation speed during polarization switching, influenced by the intrinsic domain density and phase dispersion in the film with specific Ga doping concentrations. Higher Ec samples exhibit a nucleation-dominant switching mechanism, while lower Ec samples undergo a transition from a nucleation-dominant to a propagation-dominant reversal mechanism as the electric field increases. This work introduces Ga as a viable dopant for low Ec and offers insights into material design strategies for HfO2-based ferroelectric memory applications.

2.
Nanotechnology ; 35(19)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38316045

RESUMO

Molybdenum sulfide (MoS2) as an emerging optoelectronic material, shows great potential for phototransistors owing to its atomic thickness, adjustable band gap, and low cost. However, the phototransistors based on MoS2have been shown to have some issues such as large gate leakage current, and interfacial scattering, resulting in suboptimal optoelectronic performance. Thus, Al-doped hafnium oxide (Hf1-xAlx) is proposed to be a dielectric layer of the MoS2-based phototransistor to solve this problem because of the relatively higher crystallization temperature and dielectric constant. Here, a high-performance MoS2phototransistor with Hf1-xAlxO gate dielectric layer grown by plasma-enhanced atomic layer deposition has been fabricated and studied. The results show that the phototransistor exhibits a high responsivity of 2.2 × 104A W-1, a large detectivity of 1.7 × 1017Jones, a great photo-to-dark current ratio of 2.2 × 106%, and a high external quantum efficiency of 4.4 × 106%. The energy band alignment and operating mechanism were further used to clarify the reason for the enhanced MoS2phototransistor. The suggested MoS2phototransistors could provide promising strategies in further optoelectronic applications.

3.
Clin Exp Pharmacol Physiol ; 51(8): e13902, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38886133

RESUMO

BACKGROUND: Several studies have reported a significant relationship between Ephrin receptor A2 (EphA2) and malignant progression in numerous cancers. However, there is a lack of comprehensive pan-cancer analysis on the prognostic value, mutation status, methylation landscape, and potential immunological function of EphA2. METHOD: Using The Cancer Genome Atlas, Genotype Tissue Expression Database and GEO data, we analysed the differences in EphA2 expression between normal and tumour tissues and the effects of EphA2 on the prognosis of different tumours. Furthermore, using GSCALite, cBioPortal, TISDB, ULCLAN and TIMER 2.0 databases or platforms, we comprehensively analysed the potential oncogenic mechanisms or manifestations of EphA2 in 33 different tumour types, including tumour mutation status, DNA methylation status and immune cell infiltration. The correlation of EphA2 with immune checkpoints, tumour mutational burden, DNA microsatellite instability and DNA repair genes was also calculated. Finally, the effects of EphA2 inhibitors on the proliferation of human glioma and lung cancer cells were verified in cellular experiments. RESULTS: EphA2 is differentially expressed in different tumours, and patients with overexpression have poorer overall survival. In addition, gene mutations, gene copy number variation and DNA/RNA methylation of EphA2 have been identified in various tumours. Moreover, EphA2 is positively associated with immune infiltration involving macrophages and CD8+ T cells. Further, EphA2 mRNA expression is significantly associated with immune checkpoint in various cancers, especially programmed death-ligand 1. Finally, the EphA2 inhibitor ALW-II-41-27 shows potent anti-tumour activity. CONCLUSION: Our first pan-cancer study of EphA2 provides insight into the prognostic and immunological roles of EphA2 in different tumours, suggesting that EphA2 might be a potential biomarker for poor prognosis and immune infiltration in cancer.


Assuntos
Biomarcadores Tumorais , Neoplasias , Receptor EphA2 , Humanos , Receptor EphA2/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Prognóstico , Neoplasias/imunologia , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Mutação , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral , Proliferação de Células/genética
4.
Mol Biol Evol ; 39(10)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36063436

RESUMO

As viral genomic imprints in host genomes, endogenous viral elements (EVEs) shed light on the deep evolutionary history of viruses, ancestral host ranges, and ancient viral-host interactions. In addition, they may provide crucial information for calibrating viral evolutionary timescales. In this study, we conducted a comprehensive in silico screening of a large data set of available mammalian genomes for EVEs deriving from members of the viral family Flaviviridae, an important group of viruses including well-known human pathogens, such as Zika, dengue, or hepatitis C viruses. We identified two novel pestivirus-like EVEs in the reference genome of the Indochinese shrew (Crocidura indochinensis). Homologs of these novel EVEs were subsequently detected in vivo by molecular detection and sequencing in 27 shrew species, including 26 species representing a wide distribution within the Crocidurinae subfamily and one in the Soricinae subfamily on different continents. Based on this wide distribution, we estimate that the integration event occurred before the last common ancestor of the subfamily, about 10.8 million years ago, attesting to an ancient origin of pestiviruses and Flaviviridae in general. Moreover, we provide the first description of Flaviviridae-derived EVEs in mammals even though the family encompasses numerous mammal-infecting members. This also suggests that shrews were past and perhaps also current natural reservoirs of pestiviruses. Taken together, our results expand the current known Pestivirus host range and provide novel insight into the ancient evolutionary history of pestiviruses and the Flaviviridae family in general.


Assuntos
Pestivirus , Vírus , Infecção por Zika virus , Zika virus , Animais , Evolução Molecular , Genoma Viral , Humanos , Pestivirus/genética , Filogenia , Musaranhos/genética , Vírus/genética , Zika virus/genética
5.
Biol Reprod ; 109(6): 799-811, 2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-37672213

RESUMO

Galectins are a phylogenetically conserved family of soluble ß-galactoside binding proteins. There are 16 different of galectins, each with a specific function determined by its distinct distribution and spatial structure. Galectin-13, galectin-14, and galectin-16 are distinct from other galectin members in that they are primarily found in placental tissue. These galectins, also referred to as placental galectins, play critical roles in regulating pregnancy-associated processes, such as placenta formation and maternal immune tolerance to the embedded embryo. The unique structural characteristics and the inability to bind lactose of placental galectins have recently received significant attention. This review primarily examines the novel structural features of placental galectins, which distinguish them from the classic galectins. Furthermore, it explores the correlation between these structural features and the loss of ß-galactoside binding ability. In addition, the newly discovered functions of placental galectins in recent years are also summarized in our review. A detailed understanding of the roles of placental galectins may contribute to the discovery of new mechanisms causing numerous pregnancy diseases and enable the development of new diagnostic and therapeutic strategies for the treatment of these diseases, ultimately benefiting the health of mothers and offspring.


Assuntos
Galectinas , Placenta , Feminino , Gravidez , Humanos , Placenta/metabolismo , Galectinas/química , Galectinas/metabolismo , Galactosídeos/química , Galactosídeos/metabolismo
6.
Langmuir ; 39(49): 18073-18081, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38014689

RESUMO

The defective BiOCl nanosheet exposed (001) facet with favorable photocatalytic performance was designed. The surface microstructure analysis and theoretical calculation certified the dominant exposed (001) facet and rich surface oxygen defects of Br--doped BiOCl (B-6) nanosheets. The energy level structure analysis indicates that the band gap can be narrowed and the light absorption range can be widened by introducing Br- to BiOCl, and the presence of defective energy levels increases the photogenerated carrier transfer efficiency. Moreover, the doping of Br- in BiOCl promotes the directional flow of electrons to the surface of B-6, which improves the photocatalytic performance of the sample. Thus, the Br--doped BiOCl can degrade 96.5% RhB within 6 min under visible-light irradiation with high apparent reaction rate constants of 0.51 min-1, exhibiting the strongest photocatalytic degradation performance. This work provides guidance for the preparation of Bi-based photocatalysts with excellent performance.

7.
Malar J ; 22(1): 84, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36890523

RESUMO

BACKGROUND: Hainan Province, China, has been an endemic region with high transmission of Plasmodium falciparum and Plasmodium vivax. Indigenous malaria caused by P. vivax was eliminated in Hainan in 2011, while imported vivax malaria remains. However, the geographical origin of P. vivax cases in Hainan remains unclear. METHODS: Indigenous and imported P. vivax isolates (n = 45) were collected from Hainan Province, and the 6 kb mitochondrial genome was obtained. Nucleotide (π) and haplotype (h) diversity were estimated using DnaSP. The numbers of synonymous nucleotide substitutions per synonymous site (dS) and nonsynonymous nucleotide substitutions per nonsynonymous site (dN) were calculated using the SNAP program. Arlequin software was used to estimate the genetic diversity index and assess population differentiation. Bayesian phylogenetic analysis of P. vivax was performed using MrBayes. A haplotype network was generated using the NETWORK program. RESULTS: In total, 983 complete mitochondrial genome sequences were collected, including 45 from this study and 938 publicly available from the NCBI. Thirty-three SNPs were identified, and 18 haplotypes were defined. The haplotype (0.834) and nucleotide (0.00061) diversity in the Hainan populations were higher than China's Anhui and Guizhou population, and the majority of pairwise FST values in Hainan exceeded 0.25, suggesting strong differentiation among most populations except in Southeast Asia. Most Hainan haplotypes were connected to South/East Asian and China's others haplotypes, but less connected with populations from China's Anhui and Guizhou provinces. Mitochondrial lineages of Hainan P. vivax belonged to clade 1 of four well-supported clades in a phylogenetic tree, most haplotypes of indigenous cases formed a subclade of clade 1, and the origin of seven imported cases (50%) could be inferred from the phylogenetic tree, but five imported cases (42.8%) could not be traced using the phylogenetic tree alone, necessitating epidemiological investigation. CONCLUSIONS: Indigenous cases in Hainan display high genetic (haplotype and nucleotide) diversity. Haplotype network analysis also revealed most haplotypes in Hainan were connected to the Southeast Asian populations and divergence to a cluster of China's other populations. According to the mtDNA phylogenetic tree, some haplotypes were shared between geographic populations, and some haplotypes have formed lineages. Multiple tests are needed to further explore the origin and expansion of P. vivax populations.


Assuntos
Genoma Mitocondrial , Malária Vivax , Humanos , Plasmodium vivax/genética , Filogenia , Teorema de Bayes , Malária Vivax/epidemiologia , Malária Vivax/genética , China/epidemiologia , Haplótipos , Nucleotídeos , Variação Genética
8.
Nanotechnology ; 34(21)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36745920

RESUMO

X-ray microscope as an important nanoprobing tool plays a prevailing role in nano-inspections of materials. Despite the fast advances of high resolution focusing/imaging reported, the efficiency of existing high-resolution zone plates is mostly around 5% in soft x-ray and rapidly goes down to 1%-2% when the resolution approaches 10 nm. It is well known that the rectangular zone shape, beamstop, limited height/width ratios, material absorption of light and structural defects are likely responsible for the limited efficiency. Although zone plates with Kinoform profile are supposed to be efficient, progress for achieving both high resolution (<30 nm) and high efficiency (>5%) have hardly been addressed in soft x-ray. In this work, we propose a compound Kinoform/Fresnel zone plate (CKZP) by combing a dielectric Kinoform zone plate with a 15 nm resolution zone plate. Greyscale electron beam lithography was applied to form the 3D Kinoform zone plate and atomic layer deposition was carried out to form the binary zone plate. Optical characterizations demonstrated 15 nm resolution focusing/imaging with over 7.8% efficiency in soft x-ray. The origin of the efficiency improvement behind the proposed compound lens is theoretically analyzed and discussed.

9.
Nanotechnology ; 32(21)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33535194

RESUMO

An asymmetric dual-gate (DG) MoS2field-effect transistor (FET) with ultrahigh electrical performance and optical responsivity using atomic-layer-deposited HfO2as a top-gate (TG) dielectric was fabricated and investigated. The effective DG modulation of the MoS2FET exhibited an outstanding electrical performance with a high on/off current ratio of 6 × 108. Furthermore, a large threshold voltage modulation could be obtained from -20.5 to -39.3 V as a function of the TG voltage in a DG MoS2phototransistor. Meanwhile, the optical properties were systematically explored under a series of gate biases and illuminated optical power under 550 nm laser illumination. An ultrahigh photoresponsivity of 2.04 × 105AW-1has been demonstrated with the structure of a DG MoS2phototransistor because the electric field formed by the DG can separate photogenerated electrons and holes efficiently. Thus, the DG design for 2D materials with ultrahigh photoresponsivity provides a promising opportunity for the application of optoelectronic devices.

10.
Environ Geochem Health ; 43(9): 1-11, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33559783

RESUMO

OBJECTIVES: As the largest organ of the human body, the skin is the major exposure route of NO2. However, the evidence for a relationship between NO2 exposure and dermatologic diseases (DMs) is limited. This time-series study was conducted to assess the short-term effect of nitrogen dioxide (NO2) exposure on DMs outpatient visits in Xinxiang, China. METHODS: Daily recordings of NO2 concentrations, meteorological data, and the outpatient visits data for DMs were collected in Xinxiang from January 1st, 2015, to December 31st, 2018. The analysis method used was based on the generalized additive model (GAM) with quasi-Poisson regression to investigate the relationship between NO2 exposure and DMs outpatient visits. Several covariates, such as long-term trends, seasonality, and weather conditions were controlled. RESULTS: A total of 164,270 DMs outpatients were recorded. A 10 µg/m3 increase in NO2 concentrations during the period was associated with a 1.86% increase in DMs outpatient visits (95% confidence intervals [Cl]: 1.06-2.66%). The effect was stronger (around 6 times) in the cool seasons than in warmer seasons and younger patients (< 15 years of age) appeared to be more vulnerable. CONCLUSIONS: The findings of this study indicate that short-term exposure to NO2 increases the risk of DMs in Xinxiang, China, especially in the cool seasons. Policymakers should implement more stringent air quality standards to improve air quality.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , China/epidemiologia , Humanos , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Pacientes Ambulatoriais , Material Particulado/análise
11.
Mol Biol Evol ; 36(8): 1643-1652, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31112995

RESUMO

A general south-north genetic divergence has been observed among Han Chinese in previous studies. However, these studies, especially those on mitochondrial DNA (mtDNA), are based either on partial mtDNA sequences or on limited samples. Given that Han Chinese comprise the world's largest population and reside around the whole China, whether the north-south divergence can be observed after all regional populations are considered remains unknown. Moreover, factors involved in shaping the genetic landscape of Han Chinese need further investigation. In this study, we dissected the matrilineal landscape of Han Chinese by studying 4,004 mtDNA haplogroup-defining variants in 21,668 Han samples from virtually all provinces in China. Our results confirmed the genetic divergence between southern and northern Han populations. However, we found a significant genetic divergence among populations from the three main river systems, that is, the Yangtze, the Yellow, and the Zhujiang (Pearl) rivers, which largely attributed to the prevalent distribution of haplogroups D4, B4, and M7 in these river valleys. Further analyses based on 4,986 mitogenomes, including 218 newly generated sequences, indicated that this divergence was already established during the early Holocene and may have resulted from population expansion facilitated by ancient agricultures along these rivers. These results imply that the maternal gene pools of the contemporary Han populations have retained the genetic imprint of early Neolithic farmers from different river basins, or that river valleys represented relative migration barriers that facilitated genetic differentiation, thus highlighting the importance of the three ancient agricultures in shaping the genetic landscape of the Han Chinese.


Assuntos
Genoma Humano , Genoma Mitocondrial , Rios , Agricultura , China , Demografia , Humanos , Filogeografia
12.
Hum Biol ; 91(4): 257-277, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767896

RESUMO

The Fujian Tanka people are officially classified as a southern Han ethnic group, whereas they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: (1) the Han Chinese origin, (2) the ancient Daic origin, (3) and the admixture between Daic and Han. This study addressed this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. The southern East Asian predominant haplogroups (e.g., Y-chromosome O1a1a-P203 and O1b1a1a-M95, and mtDNA F2a, M7c1, and F1a1) had relatively high frequencies in Tanka. The interpopulation comparison revealed that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages but are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song dynasty), indicating that they are an indigenous population, not late Daic migrants from southwestern China.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional/métodos , Povo Asiático/genética , China/etnologia , DNA Mitocondrial/história , Etnicidade/genética , Feminino , Testes Genéticos/métodos , Haplótipos/genética , História Antiga , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
13.
J Hum Genet ; 64(8): 703-709, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31092888

RESUMO

Paternal inheritance of both Y chromosome and surnames makes it possible to trace the origin and migration histories of surnames based on high-resolution Y chromosome phylogeny. In this study, 292 male samples with surname Ye () in China were collected to unravel the history of this surname. Among these samples, O-F492 showed the highest frequency (26.71%). Analysis based on Y chromosome genotyping data of 52,798 males from virtually the whole China revealed a close correlation between O-F492 and surname Ye. High-throughput sequencing of 131 unrelated male individuals covering all sub-haplogroups in O-F492 was conducted to update the phylogeny of O-F492. Most of the Ye individuals (43/64, 67.19%) are embedded in three major branches, i.e., O-MF1461, O-MF15219, and O-FGC66159, deriving from the same node (O-FGC66168). These three clades restrictively distributed in different regions, likely attributed to independent differentiations. Coalescent ages of the three subclades are estimated ranging from 1,925 to 1,775 years ago, probably driven by the massive migration from north to south China after Yongjia riot in Jin Dynasty, consistent with the migration history of surname Ye. Our study thus shed important light on the history of the surname Ye from genetic perspective.


Assuntos
Cromossomos Humanos Y , Genética Populacional , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Herança Paterna , China , Marcadores Genéticos , Haplótipos , Humanos , Masculino , Linhagem , Filogenia , Filogeografia , Polimorfismo de Nucleotídeo Único
14.
J Org Chem ; 84(4): 2297-2306, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30632746

RESUMO

A palladium-catalyzed ring-opening oxo-formal [3 + 2]-cycloaddition reaction of novel donor-acceptor spirovinylcyclopropyl oxindole with 3-oxindole is described. The developed protocol provides facile access to oxo-bispirooxindole derivatives in good yields (up to 82% yield) with excellent diastereoselectivities (up to 20:1 dr).

15.
Mol Biol Rep ; 46(1): 17-25, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30446962

RESUMO

Genetic polymorphism analysis of 60 mitochondrial DNA (mtDNA) loci in Chinese Xinjiang Kazak group was conducted in this study. Blood samples from 141 unrelated healthy volunteers were randomly collected from Chinese Kazak ethnic group in Ili, Xinjiang Uygur Autonomous region. Among these mtDNA loci, single nucleotide transition was the most commonly observed variant (87.93%). A total of 25 haplogroups and 79 haplotypes were found in Kazak group, and Haplogroup D4 was the most common haplogroup (21.28%). Among the entire 79 haplotypes, 53 of them were observed for only once, 14 for twice. The haplotype diversity was 0.978 ± 0.005, and the nucleotide diversity was 0.17449. The detection of (CA)n and 9-bp deletion polymorphisms could improve the discrimination power of the mtDNA genetic marker. Moreover, Xinjiang Kazak group was compared with other previously reported groups to infer its genetic background. The present results revealed that Xinjiang Kazak ethnic group was genetically closer related to Xinjiang Uygur, Xinjiang Uzbek and Xinjiang Han populations. Meanwhile, our results also indicated the potential closer genetic relationships among Xinjiang Kazak group with Altaian Kazak as well as Xinjiang Xibe group. In conclusion, this novel mtDNA panel could be effectively utilized for forensic applications. Additionally, to further reveal the genetic background of Chinese Kazak group, more relevant populations and genetic markers should be incorporated in our future study.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Técnicas de Genotipagem/métodos , Adulto , Alelos , China/etnologia , DNA Mitocondrial/sangue , Etnicidade/genética , Feminino , Frequência do Gene/genética , Marcadores Genéticos , Genética Populacional/métodos , Genótipo , Haplótipos/genética , Voluntários Saudáveis , Humanos , Masculino , Repetições de Microssatélites/genética , Mitocôndrias/genética , Filogenia , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único/genética
16.
BMC Pulm Med ; 19(1): 239, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818275

RESUMO

BACKGROUND: Bone mineral density (BMD) has been positively associated with lung function in patients diagnosed with respiratory diseases such as chronic obstructive pulmonary disease (COPD) and cystic fibrosis. However, the relationship between BMD and lung function is inconsistent in the general population. METHODS: To investigate the association between BMD and lung function in a Chinese general population, a total of 1024 adults aged 40-70 years old from Qiliying (an industrial polluted exposure area) and Langgongmiao (the reference area with non-industrial pollution) were recruited and underwent BMD and spirometry tests. RESULTS: Both BMD and lung function levels were lower in the exposed area compared to the reference area. In addition, BMD and lung function levels were also lower in females compared to males. Both Spearman and partial correlation analyses showed that BMD was positively correlated with FVC and FEV1. After adjusting linear regression analyses for potential confounding factors, every 0.1 g/cm2 drop in BMD was associated with 53.0 mL decrease in FVC and 33.5 mL decrease in FEV1. CONCLUSIONS: A reduction of BMD is associated with lower lung function in a general population from China.


Assuntos
Densidade Óssea , Pulmão/fisiologia , Adulto , Idoso , China , Estudos de Coortes , Estudos Transversais , Feminino , Volume Expiratório Forçado , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , População Rural , Espirometria , Capacidade Vital
17.
Cell Physiol Biochem ; 49(3): 1064-1073, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30196278

RESUMO

BACKGROUND/AIMS: The roots of Averrhoa carambola L. (Oxalidaceae) have long been used as a traditional Chinese medicine for the treatment of headaches, vomiting, coughing and hangovers. 2-dodecyl-6-methoxycyclohexa-2, 5-1, 4-dione (DMDD) has been isolated from A. carambola L. roots, and this study was carried out to investigate the potential beneficial effects of DMDD on neuron apoptosis and memory deficits in Alzheimer's disease. METHODS: The effects of a DMDD on learning and memory in APP/PS1 transgenic AD mice in vivo were investigated via Morris water maze and Y-type electric maze tests. In vitro, Cell viability was assessed by CCK-8. Apoptosis was assessed by Annexin V-FITC/PI flow cytometry assay, and transmission electron microscopy assay. Relative quantitative real-time PCR and Western blot were used to determine the expressions of genes and proteins. RESULTS: The spatial learning and memory deficit, fear memory deficit, as well as apoptosis and loss of neuron in hippocampal area of APP/PS1 mice were reversed by DMDD in APP/PS1 transgenic AD mice. DMDD protected against the Aß1-42-induced apoptosis, loss of mitochondria membrane potential, induction of pro-apoptotic Bcl-2 family protein Bax, reduction of anti-apoptotic Bcl-2 family proteins Bcl-2, and activation of Caspase-3, and -9 in PC-12 cells. The Bcl-2/Bax ratio was also increased in DMDD-pretreated PC-12 cells in vitro and APP/PS1 mice in vivo. CONCLUSION: DMDD has potential benefit on treating learning and memory deficit in APP/PS1 transgenic AD mice, and its effects may be associated with reversing the apoptosis of neuron via inhibiting Bax/Bcl-2 mediated mitochondrial membrane potential loss.


Assuntos
Doença de Alzheimer/patologia , Apoptose/efeitos dos fármacos , Averrhoa/química , Neurônios/metabolismo , Substâncias Protetoras/farmacologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/toxicidade , Precursor de Proteína beta-Amiloide/genética , Animais , Averrhoa/metabolismo , Caspase 3/metabolismo , Caspase 9/metabolismo , Modelos Animais de Doenças , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Células PC12 , Fragmentos de Peptídeos/toxicidade , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Substâncias Protetoras/química , Substâncias Protetoras/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
18.
Genetica ; 146(2): 211-226, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29441472

RESUMO

Many peninsulas in the temperate zone played an important role as refugia of various flora and fauna, and the southern Korean Peninsula also served as a refugium for many small mammals in East Asia during the Pleistocene. The Asian lesser white-toothed shrew, Crocidura shantungensis, is a widely distributed species in East Asia, and is an appropriate model organism for exploring the role of the Korean Peninsula as a refugium of small mammals. Here, we investigated phylogenetic relationships and genetic diversity based on the entire sequence of the mitochondrial cytochrome b gene (1140 bp). A Bayesian tree for 98 haplotypes detected in 228 C. shantungensis specimens from East Asia revealed the presence of three major groups with at least 5 subgroups. Most haplotypes were distributed according to their geographic proximity. Pairwise FST's and analysis of molecular variance (AMOVA) revealed a high degree of genetic differentiation and variance among regions as well as among populations within region, implying little gene flow among local populations. Genetic evidence from South Korean islands, Jeju-do Island of South Korea, and Taiwan leads us to reject the hypothesis of recent population expansion. We observed unique island-type genetic characteristics consistent with geographic isolation and resultant genetic drift. Phylogeographic inference, together with estimates of genetic differentiation and diversity, suggest that the southern most part the Korean Peninsula, including offshore islands, played an important role as a refugium for C. shantungensis during the Pleistocene. However, the presence of several refugia on the mainland of northeast Asia is also proposed.


Assuntos
Variação Genética , Musaranhos/genética , Animais , Citocromos b/genética , Haplótipos , Coreia (Geográfico) , Filogeografia , Musaranhos/classificação
19.
Org Biomol Chem ; 17(1): 103-107, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30520921

RESUMO

A novel palladium-catalysed ring-opening [3 + 2]-annulation of spirovinylcyclopropyl oxindole with α,ß-unsaturated nitroalkenes is reported. A series of spirooxindole derivatives were synthesized in high yields and good to excellent diastereoselectivities. This developed protocol offers a new and efficient pathway for the assembly of spirooxindoles.

20.
Eur J Nutr ; 57(7): 2583-2594, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28929400

RESUMO

PURPOSE: The enzymes encoded by fatty acid desaturases (FADS) genes determine the desaturation of long-chain polyunsaturated fatty acids (LCPUFA). We investigated if haplotype and single nucleotide polymorphisms (SNPs) in FADS gene cluster can influence LCPUFA status in infants who received either fish oil or placebo supplementation. METHODS: Children enrolled in the Infant Fish Oil Supplementation Study (IFOS) were randomly allocated to receive either fish oil or placebo from birth to 6 months of age. Blood was collected at 6 months of age for the measurement of fatty acids and for DNA extraction. A total of 276 participant DNA samples underwent genotyping, and 126 erythrocyte and 133 plasma fatty acid measurements were available for analysis. Twenty-two FADS SNPs were selected on the basis of literature and linkage disequilibrium patterns identified from the HapMap data. Haplotype construction was completed using PHASE. RESULTS: For participants allocated to the fish oil group who had two copies of the FADS1 haplotype consisting of SNP minor alleles, DHA levels were significantly higher compared to other haplotypes. This finding was not observed for the placebo group. Furthermore, for members of the fish oil group only, the minor homozygous carriers of all the FADS1 SNPs investigated had significantly higher DHA than other genotypes (rs174545, rs174546, rs174548, rs174553, rs174556, rs174537, rs174448, and rs174455). CONCLUSIONS: Overall results of this preliminary study suggest that supplementation with fish oil may only significantly increase DHA in minor allele carriers of FADS1 SNPs. Further research is required to confirm this novel finding.


Assuntos
Eritrócitos/química , Ácidos Graxos Dessaturases/genética , Ácidos Graxos/metabolismo , Óleos de Peixe/administração & dosagem , Polimorfismo de Nucleotídeo Único , Dessaturase de Ácido Graxo Delta-5 , Feminino , Humanos , Lactente , Masculino , Família Multigênica
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