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1.
Nature ; 632(8023): 69-74, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38926586

RESUMO

Chiral superconductors, a unique class of unconventional superconductors in which the complex superconducting order parameter winds clockwise or anticlockwise in the momentum space1, represent a topologically non-trivial system with intrinsic time-reversal symmetry breaking (TRSB) and direct implications for topological quantum computing2,3. Intrinsic chiral superconductors are extremely rare, with only a few arguable examples, including UTe2, UPt3 and Sr2RuO4 (refs. 4-7). It has been suggested that chiral superconductivity may exist in non-centrosymmetric superconductors8,9, although such non-centrosymmetry is uncommon in typical solid-state superconductors. Alternatively, chiral molecules with neither mirror nor inversion symmetry have been widely investigated. We suggest that an incorporation of chiral molecules into conventional superconductor lattices could introduce non-centrosymmetry and help realize chiral superconductivity10. Here we explore unconventional superconductivity in chiral molecule intercalated TaS2 hybrid superlattices. Our studies reveal an exceptionally large in-plane upper critical field Bc2,|| well beyond the Pauli paramagnetic limit, a robust π-phase shift in Little-Parks measurements and a field-free superconducting diode effect (SDE). These experimental signatures of unconventional superconductivity suggest that the intriguing interplay between crystalline atomic layers and the self-assembled chiral molecular layers may lead to exotic topological materials. Our study highlights that the hybrid superlattices could lay a versatile path to artificial quantum materials by combining a vast library of layered crystals of rich physical properties with the nearly infinite variations of molecules of designable structural motifs and functional groups11.


Assuntos
Supercondutividade , Estereoisomerismo , Condutividade Elétrica
2.
Nature ; 606(7916): 902-908, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35768590

RESUMO

The discovery of chiral-induced spin selectivity (CISS) opens up the possibility to manipulate spin orientation without external magnetic fields and enables new spintronic device designs1-4. Although many approaches have been explored for introducing CISS into solid-state materials and devices, the resulting systems so far are often plagued by high inhomogeneity, low spin selectivity or limited stability, and have difficulties in forming robust spintronic devices5-8. Here we report a new class of chiral molecular intercalation superlattices (CMIS) as a robust solid-state chiral material platform for exploring CISS. The CMIS were prepared by intercalating layered two-dimensional atomic crystals (2DACs) (such as TaS2 and TiS2) with selected chiral molecules (such as R-α-methylbenzylamine and S-α-methylbenzylamine). The X-ray diffraction and transmission electron microscopy studies demonstrate highly ordered superlattice structures with alternating crystalline atomic layers and self-assembled chiral molecular layers. Circular dichroism studies show clear chirality-dependent signals between right-handed (R-) and left-handed (S-) CMIS. Furthermore, by using the resulting CMIS as the spin-filtering layer, we create spin-selective tunnelling junctions with a distinct chirality-dependent tunnelling current, achieving a tunnelling magnetoresistance ratio of more than 300 per cent and a spin polarization ratio of more than 60 per cent. With a large family of 2DACs of widely tunable electronic properties and a vast selection of chiral molecules of designable structural motifs, the CMIS define a rich family of artificial chiral materials for investigating the CISS effect and capturing its potential for new spintronic devices.

3.
Nature ; 591(7850): 385-390, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33731947

RESUMO

Two-dimensional (2D) materials1,2 and the associated van der Waals (vdW) heterostructures3-7 have provided great flexibility for integrating distinct atomic layers beyond the traditional limits of lattice-matching requirements, through layer-by-layer mechanical restacking or sequential synthesis. However, the 2D vdW heterostructures explored so far have been usually limited to relatively simple heterostructures with a small number of blocks8-18. The preparation of high-order vdW superlattices with larger number of alternating units is exponentially more difficult, owing to the limited yield and material damage associated with each sequential restacking or synthesis step8-29. Here we report a straightforward approach to realizing high-order vdW superlattices by rolling up vdW heterostructures. We show that a capillary-force-driven rolling-up process can be used to delaminate synthetic SnS2/WSe2 vdW heterostructures from the growth substrate and produce SnS2/WSe2 roll-ups with alternating monolayers of WSe2 and SnS2, thus forming high-order SnS2/WSe2 vdW superlattices. The formation of these superlattices modulates the electronic band structure and the dimensionality, resulting in a transition of the transport characteristics from semiconducting to metallic, from 2D to one-dimensional (1D), with an angle-dependent linear magnetoresistance. This strategy can be extended to create diverse 2D/2D vdW superlattices, more complex 2D/2D/2D vdW superlattices, and beyond-2D materials, including three-dimensional (3D) thin-film materials and 1D nanowires, to generate mixed-dimensional vdW superlattices, such as 3D/2D, 3D/2D/2D, 1D/2D and 1D/3D/2D vdW superlattices. This study demonstrates a general approach to producing high-order vdW superlattices with widely variable material compositions, dimensions, chirality and topology, and defines a rich material platform for both fundamental studies and technological applications.

4.
World J Urol ; 42(1): 216, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38581575

RESUMO

BACKGROUND: Previous research has focused on the association between immune cells and the development of benign prostatic hyperplasia (BPH). Nevertheless, the causal relationships in this context remain uncertain. METHODS: This study employed a comprehensive and systematic two-sample Mendelian randomization (MR) analysis to determine the causal relationships between immunophenotypes and BPH. We examined the causal associations between 731 immunophenotypes and the risk of BPH by utilizing publicly available genetic data. Integrated sensitivity analyses were performed to validate the robustness, assess heterogeneity, and examine horizontal pleiotropy in the results. RESULTS: We discovered that 38 immunophenotypes have a causal effect on BPH. Subsequently, four of these immunophenotypes underwent verification using weighted median, weighted mode, and inverse variance weighted (IVW) algorithms, which included CD19 on CD24+ CD27+, CD19 on naive-mature B cell, HLA DR on CD14- CD16+ and HLA DR+ T cell%lymphocyte. Furthermore, BPH exhibited a significant association with three immunophenotypes: CD19 on IgD+ CD38dim (ß = -0.152, 95% CI = 0.746-0.989, P = 0.034), CD19 on IgD+ (ß = -0.167, 95% CI = 0.737-0.973, P = 0.019), and CD19 on naive-mature B cell (ß = -0.166, 95% CI = 0.737-0.972, P = 0.018). CONCLUSIONS: Our study provides valuable insights for future clinical investigations by establishing a significant association between immune cells and BPH.


Assuntos
Hiperplasia Prostática , Humanos , Masculino , Hiperplasia Prostática/genética , Análise da Randomização Mendeliana , Proteínas Adaptadoras de Transdução de Sinal , Algoritmos , Antígenos HLA-DR
5.
Genet Res (Camb) ; 2023: 2355891, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36741922

RESUMO

Chinese herbal medicine (CHM), which includes herbal slices and proprietary products, is widely used in China. Shenqi Dihuang (SQDH) is a traditional Chinese medicine (TCM) formula with ingredients that affect tumor growth. Despite recent advances in prognosis, patients with renal cell carcinoma (RCC) cannot currently receive curative treatment. The present study aimed to explore the potential target genes closely associated with SQDH. The gene expression data for SQDH and RCC were obtained from the TCMSP and TCGA databases. The SQDH-based prognostic prediction model reveals a strong correlation between RCC and SQDH. In addition, the immune cell infiltration analysis indicated that SQDH might be associated with the immune response of RCC patients. Based on this, we successfully built the prognostic prediction model using SQDH-related genes. The results demonstrated that CCND1 and NR3C2 are closely associated with the prognosis of RCC patients. Finally, the pathways enrichment analysis revealed that response to oxidative stress, cyclin binding, programmed cell death, and immune response are the most enriched pathways in CCND1. Furthermore, transcription regulator activity, regulation of cell population proliferation, and cyclin binding are closely associated with the NR3C2.


Assuntos
Carcinoma de Células Renais , Medicamentos de Ervas Chinesas , Neoplasias Renais , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/química , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Medicina Tradicional Chinesa , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/genética , Neoplasias Renais/metabolismo
6.
Pharmacol Res ; 197: 106940, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37758102

RESUMO

Small nucleolar RNA host gene 15 (SNHG15) plays an oncogenic role in many cancers. However, the role of SNHG15 in bladder cancer (BLCA) remains unclear. In this study, the regulation of SNHG15 on the activities of BLCA cells (T24 and RT112) was investigated. In detail, super-enhancers (SEs), differentially expressed genes, and functional enrichment were detected by bioinformatic analyses. Mutant cell lines lacking SNHG15-SEs were established using CRISPR-Cas9. Relative gene expression was detected by quantitative polymerase chain reaction (qPCR), western blot, in situ hybridization, and immunohistochemistry assays. Cell senescence, apoptosis, viability, and proliferation were measured. Chromatin immunoprecipitation (ChIP)-qPCR and luciferase reporter gene assays were conducted to analyze the interactions between genes. A novel super-enhancer of SNHG15 (SNHG15-SEs) was discovered in several BLCA datasets. The deletion of SNHG15-SEs resulted in a significant downregulation of SNHG15. Mechanistically, the core active region of SNHG15-SEs recruited the transcription factor FOSL1 to facilitate the SNHG15 transcription, thereby inducing the proliferation and metastasis of BLCA cells. Deletion of SNHG15-SEs inhibited the growth and metastasis of T24 and RT112 cells by inactivating the WNT/CTNNB1 pathway activation. Overexpression of FOSL1 in SNHG15-SEs restored the cell proliferation and metastasis. Next, a xenograft mouse model showed that SNHG15-SEs deletion inhibited the proliferation and metastasis of BLCA cells in vivo. Collectively, our data indicate that SNHG15-SEs recruit FOSL1 to promote the expression of SNHG15 which interacts with CTNNB1 in the nucleus to activate the transcription of ADAM12, leading to the malignance of BLCA cells.


Assuntos
Neoplasias da Bexiga Urinária , Via de Sinalização Wnt , Humanos , Animais , Camundongos , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , Células Epiteliais , Apoptose
7.
J Org Chem ; 88(17): 12698-12708, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37589746

RESUMO

Acyl radicals are significant synthetic active species in organic synthesis. However, their generation via green and compatible methods remains challenging. Herein, we report an unprecedented visible-light-mediated approach for generating aryl acyl radicals from readily available triazine esters. This protocol with mild and redox-neutral conditions affords a diverse array of oxindoles attached to alcohol groups in a single operation. The recycling of leaving groups and a range of visible-light-mediated reactions using triazine ester as an acyl radical precursor demonstrate the synthetic potential of this methodology.

8.
Parasitol Res ; 122(9): 2155-2173, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37458821

RESUMO

Fasciola hepatica is a trematode leading to heavy economic setbacks to the livestock sector globally. The population's genetic information and intimate kinship level are frequently assessed using analysis of mitochondrial DNA. In this analysis, we retrieved cox1 (n = 247) and nad1 (n = 357) sequences of F. hepatica from the NCBI GenBank database and aligned the sequences with the respective reference sequences using MEGA software. The median joining network was drawn using PopArt software while neutrality and diversity indices were estimated with the help of DnaSp software. Neighbor-joining phylogenetic tree was constructed using the MEGA software package. A total of 46 and 98 distinctive haplotypes were observed for cox1 and nad1 genes, respectively. Diversity indices indicated high haplotype and nucleotide diversities in both genes. Positive Tajima's D and Fu's Fs values were found for the entire population of both the genes under study. The cox1 and nad1 gene segments in this study showed high Tajima's D values, suggesting a low likelihood of future population growth. The Tajima's D value of the nad1 gene sequence is lower (2.14910) than that of the cox1 gene sequence (3.40314), which suggests that the former is growing at a slower rate. However, the region-wise analysis revealed that both the cox1 and nad1 genes showed deviation from neutrality suggesting a recent population expansion as a result of an excess of low-frequency polymorphism. Furthermore, the overall host-wise analysis showed positive and significant Tajima's D values for the cox1 and nad1 gene sequences. To the best of our knowledge, this is the first attempt to provide insights into genetic variations and population structure of F. hepatica at a global scale using cox1 and nad1 genes. Our findings suggest the existence of specific variants of F. hepatica in different parts of the world and provide information on the molecular ecology of F. hepatica. The results of this study also mark a critical development in upcoming epidemiological investigations on F. hepatica and will also contribute to understanding the global molecular epidemiology and population structure of F. hepatica.


Assuntos
Fasciola hepatica , Animais , Fasciola hepatica/genética , Filogenia , Variação Genética , DNA Mitocondrial/genética , Haplótipos
9.
Parasitol Res ; 122(5): 1107-1126, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36933066

RESUMO

The identification of additional Echinococcus granulosus sensu lato (s.l.) complex species/genotypes in recent years raises the possibility that there might be more variation among this species in China than is currently understood. The aim of this study was to explore intra- and inter-species variation and population structure of Echinococcus species isolated from sheep in three areas of Western China. Of the isolates, 317, 322, and 326 were successfully amplified and sequenced for cox1, nad1, and nad5 genes, respectively. BLAST analysis revealed that the majority of the isolates were E. granulosus s.s., and using the cox1, nad1, and nad5 genes, respectively, 17, 14, and 11 isolates corresponded to Elodea canadensis (genotype G6/G7). In the three study areas, G1 genotypes were the most prevalent. There were 233 mutation sites along with 129 parsimony informative sites. A transition/transversion ratio of 7.5, 8, and 3.25, respectively, for cox1, nad1, and nad5 genes was obtained. Every mitochondrial gene had intraspecific variations, which were represented in a star-like network with a major haplotype with observable mutations from other distant and minor haplotypes. The Tajima's D value was significantly negative in all populations, indicating a substantial divergence from neutrality and supporting the demographic expansion of E. granulosus s.s. in the study areas. The phylogeny inferred by the maximum likelihood (ML) method using nucleotide sequences of cox1-nad1-nad5 further confirmed their identity. The nodes assigned to the G1, G3, and G6 clades as well as the reference sequences utilized had maximal posterior probability values (1.00). In conclusion, our study confirms the existence of a significant major haplotype of E. granulosus s.s. where G1 is the predominant genotype causing of CE in both livestock and humans in China.


Assuntos
Equinococose , Echinococcus granulosus , Animais , Humanos , Ovinos , Echinococcus granulosus/genética , Tibet , Equinococose/epidemiologia , Equinococose/veterinária , China , Genótipo , Haplótipos , Mutação , Filogenia , Variação Genética
10.
Genome Res ; 29(11): 1805-1815, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31649058

RESUMO

Hybridization drives rapid speciation by shaping novel genotypic and phenotypic profiles. Genomic incompatibility and transcriptome shock have been observed in hybrids, although this is rarer in animals than in plants. Using the newly sequenced genomes of the blunt snout bream (Megalobrama amblycephala [BSB]) and the topmouth culter (Culter alburnus [TC]), we focused on the sequence variation and gene expression changes in the reciprocal intergeneric hybrid lineages (F1-F3) of BSB × TC. A genome-wide transcriptional analysis identified 145-974 expressed recombinant genes in the successive generations of hybrid fish, suggesting the rapid emergence of allelic variation following hybridization. Some gradual changes of gene expression with additive and dominance effects and various cis and trans regulations were observed from F1 to F3 in the two hybrid lineages. These asymmetric patterns of gene expression represent the alternative strategies for counteracting deleterious effects of the subgenomes and improving adaptability of novel hybrids. Furthermore, we identified positive selection and additive expression patterns in transforming growth factor, beta 1b (tgfb1b), which may account for the morphological variations of the pharyngeal jaw in the two hybrid lineages. Our current findings provide insights into the evolution of vertebrate genomes immediately following hybridization.


Assuntos
Alelos , Cyprinidae/genética , Hibridização Genética , Animais , Feminino , Masculino , Polimorfismo Genético , Análise de Sequência/métodos , Especificidade da Espécie
11.
Nat Mater ; 20(6): 818-825, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33649563

RESUMO

The discovery of intrinsic ferromagnetism in ultrathin two-dimensional van der Waals crystals opens up exciting prospects for exploring magnetism in the ultimate two-dimensional limit. Here, we show that environmentally stable CrSe2 nanosheets can be readily grown on a dangling-bond-free WSe2 substrate with systematically tunable thickness down to the monolayer limit. These CrSe2/WSe2 heterostructures display high-quality van der Waals interfaces with well-resolved moiré superlattices and ferromagnetic behaviour. We find no apparent change in surface roughness or magnetic properties after months of exposure in air. Our calculations suggest that charge transfer from the WSe2 substrate and interlayer coupling within CrSe2 play a critical role in the magnetic order in few-layer CrSe2 nanosheets. The highly controllable growth of environmentally stable CrSe2 nanosheets with tunable thickness defines a robust two-dimensional magnet for fundamental studies and potential applications in magnetoelectronic and spintronic devices.

12.
BMC Psychiatry ; 22(1): 328, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35538454

RESUMO

BACKGROUND: Previous studies on the association of online courses and mental health were mainly conducted in universities, and no study investigated the relationship between characteristics of online courses and children's mental health in primary and secondary school. This study aimed to explore the association of online courses and children's mental health in primary and secondary school. METHODS: A cross-sectional study was conducted through an online survey among 540 primary and secondary school students and their parents in the eastern, central and western region of China from April to May in 2020. Children's mental health was assessed by the Strengths and Difficulties Questionnaire (SDQ). Borderline mental health problems (SDQ total difficulties score ≥ 16) and mental health problems (SDQ total difficulties score ≥ 20) were defined according to Goodman's standard. Multivariable linear and logistic regression models were used to examine the association between online courses and children's mental health. RESULTS: Compared with those who did not have problems of online courses, children having the difficulty in understanding the content of online courses had a higher SDQ total difficulties score [ß = 1.80, 95% confidence interval (CI): 0.89, 2.71] and a higher risk of borderline mental health problems [odds ratio (OR) = 1.93, 95%CI: 1.07, 3.49], while device or internet connection problems were not significantly associated with children's mental health. Compared with children who had live courses, those having video-recorded courses had a higher SDQ total difficulties score (ß = 0.90, 95%CI: 0.01, 1.80). Children who spent more than 4 h on online courses had a higher SDQ total difficulties score than those of less than or equal to 4 h (ß = 0.95, 95%CI: 0.09, 1.81). CONCLUSION: We found that online courses with inappropriate characteristics were associated with children's mental health. The findings called for the efforts to optimize the online courses and improve children's mental health.


Assuntos
Transtornos Mentais , Saúde Mental , Criança , China , Estudos Transversais , Humanos , Pais/psicologia , Inquéritos e Questionários
13.
Parasitol Res ; 121(12): 3455-3466, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36149499

RESUMO

Parasitic infection is one of the many challenges facing livestock production globally. Cysticercosis tenuicollis is a common parasitic disease in domestic and wild ruminants (intermediate host) caused by the larval stage of Taenia hydatigena that primarily infects dogs (definitive host). Although genetic studies on this parasite exist, only a few describe the genetic variation of this parasite in Mongolia. Our aim was thus, to identify the mitochondrial differences in ovine isolates of Cysticercus tenuicollis entering China from Mongolia and comparison with existing Chinese isolates from sheep and goats based on the recently described PCR-RFLP method and mitochondrial genes of NADH dehydrogenase subunit 4 (nad4) and the NADH dehydrogenase subunit 5 (nad5). Sixty-nine isolates were collected during routine veterinary meat inspections from sheep that originated from Mongolia, at the modern slaughterhouses in Erenhot City, Inner Mongolia. Additional 114 cysticerci were also retrieved from sheep and goats from northern (Inner Mongolia Autonomous Region, Ningxia Hui Autonomous Region, and Gansu Province), western (Tibet Autonomous Region), and southern (Jiangxi Province and Guangxi Province) China. The PCR-RFLP approach of the nad5 showed nine mitochondrial subclusters A1, A2, A3, A5, A8, A9, A10, A11, and B of T. hydatigena isolates from sheep and goats from Mongolia and China. Meanwhile, haplogroup A1 RFLP profile was more widespread than other variants. These data supplements existing information on the molecular epidemiology of T. hydatigena in China and Mongolia and demonstrate the occurrence of similar genetic population structures in both countries.


Assuntos
Cisticercose , Doenças dos Ovinos , Taenia , Ovinos , Animais , Cães , Taenia/genética , Cysticercus/genética , Mongólia/epidemiologia , Variação Genética , Filogenia , China , Cisticercose/epidemiologia , Cisticercose/veterinária , Cisticercose/parasitologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Cabras
14.
Zhonghua Nan Ke Xue ; 28(1): 48-55, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-37459078

RESUMO

Objective: To evaluate the effect of Modified Shenqi Dihuang Decoction (MSDD) on human hormone-sensitive LNCaP prostate cancer cells and its action mechanism. METHODS: LNCaP prostate cancer cells were treated with MSDD, followed by detection of the proliferation and apoptosis of the cells by MTT assay and flow cytometry respectively and measurement of glucose uptake and lactate production by glucose uptake assay and colorimetry respectively. The expressions of the apoptosis-related proteins Bcl-2, Bax and cleaved-caspase-3, glycolysis-related proteins HK2, GLUT1, PKM2 and LDHA, and PI3K/AKT/mTOR pathway-related proteins in the LNCaP cells were determined by Western blot. The effect of MSDD on the LNCaP cells was observed with the glycolysis inducer oligomycin and the PI3K activator 740 Y-P. RESULTS: MSDD inhibited the proliferation, induced the apoptosis, increased the levels of Bax and cleaved-caspase 3 and decreased the level of Bcl-2 in the LNCaP cells in a dose-dependent manner. After MSDD intervention, the glucose uptake and lactate production in the LNCaP cells were significantly reduced, the expressions of HK2, GLUT1, PKM2 and LDHA and the phosphorylation levels of Akt, PI3K and mTOR were markedly suppressed. Oligomycin and 740 Y-P reversed the inhibitory effect of MSDD on the proliferation of the LNCaP cells, and 740 Y-P reversed that on glucose uptake, lactic acid production and the expressions of the glycolysis-related proteins HK2, GLUT1, PKM2 and LDHA in the LNCaP cells. CONCLUSIONS: Modified Shenqi Dihuang Decoction inhibits the proliferation of LNCaP prostate cancer cells by suppressing glycolysis and the PI3K/Akt/mTOR signaling pathway.

15.
Parasitology ; 148(3): 311-326, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33092662

RESUMO

Cysticercosis caused by the metacestode larval stage of Taenia hydatigena formerly referred to as Cysticercus tenuicollis is a disease of veterinary importance that constitutes a significant threat to livestock production worldwide, especially in endemic regions due to condemnation of visceral organs and mortality rate of infected young animals. While the genetic diversity among parasites is found to be potentially useful in many areas of research including molecular diagnostics, epidemiology and control, that of T. hydatigena across the globe remains poorly understood. In this study, analysis of the mitochondrial DNA (mtDNA) of adult worms and larval stages of T. hydatigena isolated from dogs, sheep and a wild boar in China showed that the population structure consists of two major haplogroups with very high nucleotide substitutions involving synonymous and non-synonymous changes. Compared with other cestodes such as Echinococcus spp., the genetic variation observed between the haplogroups is sufficient for the assignment of major haplotype or genotype division as both groups showed a total of 166 point-mutation differences between the 12 mitochondrial protein-coding gene sequences. Preliminary analysis of a nuclear protein-coding gene (pepck) did not reveal any peculiar changes between both groups which suggests that these variants may only differ in their mitochondrial makeup.


Assuntos
DNA de Helmintos/genética , DNA Mitocondrial/genética , Taenia/genética , Teníase/veterinária , Sequência de Aminoácidos , Animais , China , DNA de Helmintos/química , DNA de Helmintos/metabolismo , DNA Mitocondrial/química , DNA Mitocondrial/metabolismo , Doenças do Cão/parasitologia , Cães , Haplótipos , Larva/genética , Larva/crescimento & desenvolvimento , Filogenia , Alinhamento de Sequência , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico , Sus scrofa , Suínos , Doenças dos Suínos/parasitologia , Taenia/crescimento & desenvolvimento , Taenia/metabolismo , Teníase/parasitologia
16.
Parasitology ; 148(7): 879-886, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33757604

RESUMO

Echinococcus shiquicus is currently limited to the Qinghai­Tibet plateau, a large mountainous region in China. Although the zoonotic potential remains unknown, progress is being made on the distribution and intermediate host range. In this study, we report E. shiquicus within Gansu and Qinghai provinces in regions located not only around the central areas but also the southeast edge of the plateau and describe their genetic relationship with previous isolates from the plateau. From 1879 plateau pikas examined, 2.39% (95% CI 1.79­3.18) were infected with E. shiquicus. The highest prevalence of 10.26% (4.06­23.58) was recorded in Makehe town, Qinghai province. Overall the prevalence was marginally higher in Qinghai (2.5%, CI 1.82­3.43) than in Gansu (2%, CI 1.02­3.89). The cox1 and nad1 genes demonstrated high and low haplotype and nucleotide diversities, respectively. The median-joining network constructed by the cox1­nad1 gene sequences demonstrated a star-like configuration with a median vector (unsampled haplotype) occupying the centre of the network. No peculiar distinction or common haplotype was observed in isolates originating from the different provinces. The presence of E. shiquicus in regions of the southeast and northeast edges of the Qinghai­Tibet plateau and high genetic variation warrants more investigation into the haplotype distribution and genetic polymorphism by exploring more informative DNA regions of the mitochondrial genome to provide epidemiologically useful insight into the population structure of E. shiquicus across the plateau and its axis.


Assuntos
Distribuição Animal , Equinococose/veterinária , Echinococcus/isolamento & purificação , Lagomorpha , Animais , Equinococose/epidemiologia , Equinococose/parasitologia , Dinâmica Populacional , Prevalência , Tibet
17.
Bioorg Med Chem ; 28(7): 115379, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32098708

RESUMO

Enhancer of Zeste Homolog 2 (EZH2) is highly expressed in kinds of malignant tumors and related to tumor occurrence, development, and prognosis. EZH2 is the catalytic subunit of the polycomb repressive complex 2 (PRC2), which promotes cell proliferation, migration, and invasion by epigenetic regulation of anti-tumor gene. It can activate numerous tumor-associated signaling pathways and interfere with DNA damage repair. In recent years, large amounts of studies have shown that EZH2 is closely related to gynecologic-related malignancies and can be used as a potential target gene for the treatment of gynecological-related malignancies. This review summarizes the oncogenic function of EZH2 and introduces the recent advances in the development of EZH2 inhibitors. On this basis, future research prospect of EZH2 is proposed.


Assuntos
Antineoplásicos/farmacologia , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias dos Genitais Femininos/tratamento farmacológico , Neoplasias dos Genitais Femininos/enzimologia , Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Humanos
18.
Molecules ; 25(4)2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32059523

RESUMO

Hyperglycemia is a strong risk factor for chronic complications of diabetes. Hyperglycemic conditions foster not only the production of reactive oxygen species (ROS), but also the consumption of antioxidants, leading to oxidative stress and promoting the occurrence and progression of complications. During our continuous search for antioxidant constituents from the pericarp of Toona sinensis (A. Juss.) Roem, we isolated two previously unreported apotirucallane-type triterpenoids, toonasinensin A (1) and toonasinensin B (2), together with five known apotirucallane-type triterpenoids (3-7) and two known cycloartane-type triterpenoids (8-9) from the pericarp. Compounds 8-9 were obtained from T. sinensis for the first time. Their structures were characterized based on interpretation of spectroscopic data (1D, 2D NMR, high-resolution electrospray ionization mass spectra, HR-ESI-MS) and comparison to previous reports. Compounds (2, 4, 6, 7, and 9) were able to inhibit proliferation against rat glomerular mesangial cells (GMCs) cultured under high-glucose conditions within a concentration of 80 µM. Compounds (2, 6, and 7) were tested for antioxidant activity attributable to superoxide dismutase (SOD), malondialdehyde (MDA), and ROS in vitro, and the results showed that compounds (2, 6, and 7) could significantly increase the levels of SOD and reduce the levels of MDA and ROS. The current studies showed that apotirucallane-type triterpenoids (2, 6, and 7) might have the antioxidant effects against diabetic nephropathy.


Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Meliaceae/química , Triterpenos/farmacologia , Animais , Técnicas de Cultura de Células , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/patologia , Glucose/toxicidade , Humanos , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo , Triterpenos/química , Triterpenos/isolamento & purificação
19.
Korean J Parasitol ; 58(1): 93-97, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32145734

RESUMO

The cestode Taenia hydatigena uses canids, primarily dogs, as definitive hosts, while the metacestode larval stage cysticercus infects a range of intermediate hosts, including domestic animals such as goats, sheep, and pigs. Cysticercosis due to T. hydatigena has large veterinary and economic drawbacks. Like other taeniids, e.g., Echinococcus, intraspecific variation is found among the members of the genus Taenia. In Africa, few studies are available on the epidemiology and distribution of T. hydatigena, and even fewer studies are available on its genetic variation. In this study, we molecularly identified 11 cysticerci from sheep in Sudan and demonstrated the genetic variation based on the NADH dehydrogenase subunit 1 (nad1) and cytochrome c oxidase subunit 1 (cox1) mitochondrial genes. The isolates were correctly identified as T. hydatigena with more than 99% similarity to those in the GenBank database. Low diversity indices and insignificant neutrality indices were observed, with 3 and 2 haplotypes for the nad1 and cox1 genes, respectively. The results suggest the presence of unique T. hydatigena haplotypes in Sudan, as haplotypes with 100% similarity were not found in the GenBank database. With few available studies on the genetic variation of T. hydatigena in Africa, this report represents the first insights into the genetic variation of T. hydatigena in Sudan and constitutes useful data.


Assuntos
Ovinos/parasitologia , Taenia/genética , Taenia/isolamento & purificação , Animais , Variação Genética , Sudão
20.
BMC Infect Dis ; 19(1): 854, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619188

RESUMO

BACKGROUND: Taenia hydatigena, T. multiceps, T. pisiformis, and Dipylidium caninum are four common large and medium-sized tapeworms parasitizing the small intestine of dogs and other canids. These parasites cause serious impact on the health and development of livestock. However, there are, so far, no commercially available molecular diagnostic kits capable of simultaneously detecting all four parasites in dogs. The aim of the study was therefore to develop a multiplex PCR assay that will accurately detect all four cestode infections in one reaction. METHODS: Specific primers for a multiplex PCR were designed based on corresponding mitochondrial genome sequences, and its detection limit was assessed by serial dilutions of the genomic DNAs of tapeworms examined. Furthermore, field samples of dog feces were tested using the developed assay. RESULTS: A multiplex polymerase chain reaction (PCR) assay was developed based on mitochondrial DNA (mtDNA) that accurately and simultaneously identify four cestode species in one reaction using specific fragment sizes of 592, 385, 283, and 190 bp for T. hydatigena, T. multiceps, T. pisiformis, and D. caninum, respectively. The lowest DNA concentration detected was 1 ng for T. hydatigena, T. multiceps and T. pisiformis, and 0.1 ng for D. caninum in a 25 µl reaction system. This assay offers high potential for the rapid detection of these four tapeworms in host feces simultaneously. CONCLUSIONS: This study provides an efficient tool for the simultaneous detection of T. hydatigena, T. multiceps, T. pisiformis, and D. caninum. The assay will be potentially useful in epidemiological studies, diagnosis, and treatment of these four cestodes infections during prevention and control program.


Assuntos
Cestoides , Infecções por Cestoides , Técnicas Microbiológicas/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Animais , Cestoides/genética , Cestoides/isolamento & purificação , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/parasitologia , Cães
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