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1.
Molecules ; 29(8)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38675596

RESUMEN

In this paper, two experimental procedures are reported, namely electro-deposition in the ultrathin liquid layer and chemical micro-etching. Firstly, a large area quasi-two-dimensional periodic membrane with adjustable density is deposited on a Si substrate driven by half-sinusoidal voltage, which is composed of raised ridges and a membrane between the ridges. The smaller the voltage frequency is, the larger the ridge distance is. The height of a raised ridge changes synchronously with the amplitude. The grain density distribution of membrane and raised ridge is uneven; the two structures change alternately, which is closely related to the change of growth voltage and copper ion concentration during deposition. The structural characteristics of membrane provide favorable conditions for micro-etching; stable etching speed and microscope real-time monitoring are the keys to achieve accurate etching. In the chemical micro-etching process, the membrane between ridges is removed, retaining the raised ridges, thus a large scale ordered micro-nano wires array with lateral growth was obtained. This method is simple and controllable, can be applied to a variety of substrates, and is the best choice for designing and preparing new functional materials. This experiment provides a basis for the extension of this method.

2.
Environ Pollut ; 344: 123343, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38219895

RESUMEN

Large petrochemical complex (PC) widely exists in both developing and developed countries, and is expected to have a special photochemical pollution in local scale due to huge VOCs emissions. Here, a typical large-scale PC in North China was selected as the study case, to explore the character, formation and influence of local photochemical pollution regarding PCs based on an improved 0-D chemical model. In the study PC, VOCs-rich character was apparent with THCs level of 90.8 ± 28.0 ppb and THCs/NOx ratio of ∼26.2 mol/mol. Severe O3 pollution was found in warm months with monthly mean MDA1O3 of 67.3-96.0 ppb. Model simulations showed the heavy O3 pollution in this PC was attributed to high precursors rather than to unfavorable meteorology, and was more sensitive to NOx (with response of 1.42 g/g) than to THCs (with response of 0.12 g/g). The photochemical pollution formation potential of the emission plumes of this PC was very enormous, with production rate of 19.6 ppb h-1 for O3, 2.9 ppb h-1 for HCHO and 1.1 ppb h-1 for CH3CHO on daytime average, 1-5 greater than in normal urban areas. The higher production rates happened in morning hours, which explained the earlier peak time of observed O3 in PCs. And about 70% of photochemical pollution (represented by O3) would be transported to surroundings, leading to the significant photochemical-pollution hazard to the vicinity of PCs.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Compuestos Orgánicos Volátiles , Ozono/análisis , Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente , Compuestos Orgánicos Volátiles/análisis , China
3.
Zootaxa ; 5129(3): 422-431, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-36101128

RESUMEN

The Chinese leafhopper species of the genus Phlogothamnus Ishihara,1961 are reviewed, and a new species Phlogothamnus circinatus sp. nov., is described and illustrated from Guizhou Province, China. And the species Phlogothamnus fanjingshanensis Li, 2011 treated as Phlogotettix fanjingshanensis (Li, 2011) comb. nov.. A key is given to separate all species of the genus from China. The type specimens of the new species are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC).


Asunto(s)
Hemípteros , Animales , China , Humanos , Universidades
4.
Zootaxa ; 5169(1): 87-92, 2022 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-36101252

RESUMEN

A new leafhopper species, Tambocerus fanjingensis sp. nov., is described and illustrated from Guizhou Province, China. A checklist of the Chinese species of Tambocerus is provided and a key based on the male genitalia is given to distinguish the Chinese species of the genus. The type specimens of the new species are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC).


Asunto(s)
Hemípteros , Animales , China , Genitales Masculinos , Humanos , Masculino , Universidades
6.
Diab Vasc Dis Res ; 19(4): 14791641221122918, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35989592

RESUMEN

OBJECTIVES: We aimed to explore the shared and specific signalling pathways involved in diabetic retinopathy (DR), diabetic peripheral neuropathy (DPN) and diabetic nephropathy (DN). METHODS: Differentially expressed mRNAs and lncRNAs were identified by high-throughput sequencing. Subsequently, functional enrichment analysis, protein-protein interaction (PPI) analysis and lncRNAs-mRNAs networks were conducted to determine the pathogenic mechanisms underlying DR, DPN and DN. RESULTS: Twenty-six biological pathways were shared among DR, DPN and DN groups compared to the type 2 diabetes mellitus (T2DM) group without complications, and most of the shared pathways and core proteins were involved in immune and inflammatory responses of microvascular damage. Cytokine‒cytokine receptor interactions and chemokine signalling pathway were the most significant and specific pathways for DR, and the lncRNA‒mRNA regulatory networks affected DR by targeting these pathways. Sphingolipid metabolism and neuroactive ligand-receptor pathways were found to be specific for the pathogenesis of DPN. Moreover, multiple amino acid metabolic pathways were involved in the occurrence and progression of DN. CONCLUSIONS: Diabetic retinopathy, DPN and DN exhibited commonality and heterogeneity simultaneously. The shared pathologic mechanisms underlying these diabetic complications are involved in diabetic microvascular damage via immune and inflammatory pathways. Our findings predict several biomarkers and therapeutic targets for these diabetic complications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Neuropatías Diabéticas , Retinopatía Diabética , ARN Largo no Codificante , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/genética , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/genética , Neuropatías Diabéticas/etiología , Neuropatías Diabéticas/genética , Retinopatía Diabética/patología , Secuenciación de Nucleótidos de Alto Rendimiento , ARN Largo no Codificante/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
7.
J Basic Microbiol ; 62(12): 1457-1466, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35925551

RESUMEN

Phenyllactic acid (PLA) has gained a lot of attention due to its broad antimicrobial activity, but the mechanism of its antifungal action has been barely reported until now. Herein, the inhibitory activity of PLA against Aspergillus flavus spore germination and its mechanism were preliminarily investigated. Results indicated that PLA had a strong antifungal activity against A. flavus with the minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) of 6 and 12 mg/ml, respectively. As observed by scanning electron microscopy (SEM), the A. flavus spores displayed wrinkled and shrunken appearance after treatment with PLA. In addition, the permeability and integrity of A. flavus cell membrane were changed obviously after PLA treatment as indicated by the propidium iodide (PI) staining results, which was further confirmed by a rise in electric conductivity and increased leakage of intracellular protein and nucleic acid. Furthermore, reduced activities of mitochondrial ATPase and dehydrogenases caused by PLA were also observed in A. flavus spores, with a result of remarkable decrease in ATP synthesis. Therefore, it could be concluded that PLA was effective in inhibiting spore germination of A. flavus mainly by disrupting cell membrane and interfering with mitochondrial energy metabolism.


Asunto(s)
Antifúngicos , Aspergillus flavus , Aspergillus flavus/metabolismo , Antifúngicos/farmacología , Antifúngicos/metabolismo , Esporas Fúngicas/metabolismo , Poliésteres/metabolismo
8.
Anal Chim Acta ; 1198: 339559, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35190125

RESUMEN

As most single tumor markers have low sensitivity or specificity, the joint detection of multiple tumor biomarkers is helpful to improve the positive rate and specificity of early diagnosis. To establish a sensitive, specific, and rapid screening method for ovarian cancer, two enzyme-free logic gates were developed to realize the joint detection of carbohydrate antigen 125 (CA125) and carcinoembryonic antigen (CEA). G-quadruplex with peroxidase activity was used as a chromogenic catalyst in this colorimetric diagnosis. For NOR gate, in the absence of CEA and CA125, template DNA (Tem-DNA), CEA aptamer with half of the G-quadruplex sequence (CEA-apt), and CA125 aptamer with the other half of the G-quadruplex sequence (CA125-apt) form a double-stranded DNA equipped with one G-quadruplex structure which can strongly combine with hemin to obtain the peroxidase-like activity; here, the output of this NOR gate is set as 1, which could exclude the risk of ovarian cancer. For AND gate, CEA-apt and CA125-apt are separated from magnetic beads in the co-existence of the dual biomarkers. After adding Tem-DNA, the G-quadruplex structure constructs with hemin to exhibit the output as 1, presenting a high risk of ovarian cancer. Under the optimized condition, this novel assay can not only show a sharp color difference between physiological state and pathological state, but also be employed for the quantitative analysis of every single biomarker. The linear detection range and detection limit for CEA are 5-500 ng mL-1 and 0.88 ng mL-1, while they are for CA125 are 35-500 U mL-1 and 0.91 U mL-1, respectively. Moreover, the established approach was successfully applied in detecting CA125 and CEA in human serum samples, which provides great promise in the fields of clinical examination and disease diagnosis.


Asunto(s)
G-Cuádruplex , Neoplasias Ováricas , Biomarcadores de Tumor , Antígeno Ca-125 , Antígeno Carcinoembrionario , Hemina/química , Humanos , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética
9.
Zootaxa ; 4966(2): 245250, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-34186618

RESUMEN

A new leafhopper genus of Athysanini from China, Fuscmacula gen. nov. with F. biprocessa sp. nov. as type species is described and illustrated. This species was collected from grass. The type specimens of the new species are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC).


Asunto(s)
Hemípteros/clasificación , Animales , China , Poaceae
10.
Front Endocrinol (Lausanne) ; 12: 774608, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35046894

RESUMEN

Objective: Gestational diabetes mellitus (GDM) is one of the most common complications of pregnancy, and its pathogenesis is still unclear. Studies have shown that circular RNAs (circRNAs) can regulate blood glucose levels by targeting mRNAs, but the role of circRNAs in GDM is still unknown. Therefore, a joint microarray analysis of circRNAs and their target mRNAs in GDM patients and healthy pregnant women was carried out. Methods: In this study, microarray analyses of mRNA and circRNA in 6 GDM patients and 6 healthy controls were conducted to identify the differentially expressed mRNA and circRNA in GDM patients, and some of the discovered mRNAs and circRNAs were further validated in additional 56 samples by quantitative realtime PCR (qRT-PCR) and droplet digital PCR (ddPCR). Results: Gene ontology and pathway analyses showed that the differentially expressed genes were significantly enriched in T cell immune-related pathways. Cross matching of the differentially expressed mRNAs and circRNAs in the top 10 KEGG pathways identified 4 genes (CBLB, ITPR3, NFKBIA, and ICAM1) and 4 corresponding circRNAs (circ-CBLB, circ-ITPR3, circ-NFKBIA, and circ-ICAM1), and these candidates were subsequently verified in larger samples. These differentially expressed circRNAs and their linear transcript mRNAs were all related to the T cell receptor signaling pathway, and PCR results confirmed the initial microarray results. Moreover, circRNA/miRNA/mRNA interactions and circRNA-binding proteins were predicted, and circ-CBLB, circ-ITPR3, and circ-ICAM1 may serve as GDM-related miRNA sponges and regulate the expression of CBLB, ITPR3, NFKBIA, and ICAM1 in cellular immune pathways. Conclusion: Upregulation of T cell receptor signaling pathway components may represent the major pathological mechanism underlying GDM, thus providing a potential approach for the prevention and treatment of GDM.


Asunto(s)
Diabetes Gestacional/metabolismo , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal , Femenino , Ontología de Genes , Humanos , Análisis por Micromatrices , Embarazo , ARN Circular/metabolismo , ARN Mensajero/metabolismo , Regulación hacia Arriba
11.
Genomics Proteomics Bioinformatics ; 18(5): 489-500, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32822870

RESUMEN

Solar energy, which is essential for the origin and evolution of all life forms on Earth, can be objectively recorded through attributes such as climatic ambient temperature (CAT), ultraviolet radiation (UVR), and sunlight duration (SD). These attributes have specific geographical variations and may cause different adaptation traits. However, the adaptation profile of each attribute and the selective role of solar energy as a whole during human evolution remain elusive. Here, we performed a genome-wide adaptation study with respect to CAT, UVR, and SD using the Human Genome Diversity Project-Centre Etude Polymorphism Humain (HGDP-CEPH) panel data. We singled out CAT as the most important driving force with the highest number of adaptive loci (6 SNPs at the genome-wide 1 × 10-7 level; 401 at the suggestive 1 × 10-5 level). Five of the six genome-wide significant adaptation SNPs were successfully replicated in an independent Chinese population (N = 1395). The corresponding 316 CAT adaptation genes were mostly involved in development and immunity. In addition, 265 (84%) genes were related to at least one genome-wide association study (GWAS)-mapped human trait, being significantly enriched in anthropometric loci such as those associated with body mass index (χ2; P < 0.005), immunity, metabolic syndrome, and cancer (χ2; P < 0.05). For these adaptive SNPs, balancing selection was evident in Euro-Asians, whereas obvious positive and/or purifying selection was observed in Africans. Taken together, our study indicates that CAT is the most important attribute of solar energy that has driven genetic adaptation in development and immunity among global human populations. It also supports the non-neutral hypothesis for the origin of disease-predisposition alleles in common diseases.


Asunto(s)
Estudio de Asociación del Genoma Completo , Desarrollo Humano , Inmunidad , Temperatura , Alelos , Humanos , Polimorfismo de Nucleótido Simple , Luz Solar , Rayos Ultravioleta
12.
Nanoscale ; 12(28): 15443-15452, 2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32662491

RESUMEN

Two-dimensional (2D) black phosphorene (BP) field-effect transistors (FETs) show excellent device performance but suffer from serious instability under ambient conditions. Isoelectronic 2D germanium selenide (GeSe) shares many similar properties with 2D BP, such as high carrier mobility and anisotropy, but is stable under ambient conditions. Herein, we explore the quantum transport properties of sub-5 nm ML GeSe MOSFETs using first-principles quantum transport simulation. A p-type (zigzag-directed) device is superior to other types (n- and p-type armchair-directed and n-type zigzag-directed). The on-state current of p-type devices (zigzag-directed), even at a 1 nm gate-length, can fulfill the requirements of high-performance applications for the next decade in the International Technology Roadmap for Semiconductors (ITRS, 2013 version). To the best of our knowledge, these ML GeSe MOSFETs have the smallest gate-length that can fulfill the ITRS HP on-state current requirements among reported 2D material FETs.

13.
Analyst ; 144(6): 2179-2185, 2019 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-30768083

RESUMEN

An ultrasensitive electrochemical detection of the androgen receptor (AR) was developed based on the protection of a DNA duplex by the AR from restriction endonuclease-mediated digestion and a subsequent hybridization chain reaction (HCR). Two partially complementary DNA probes P1 and P2 were designed to form an androgen receptor binding probe (ARBP) through hybridization. The ARBP contains a duplex at one end and two single-stranded tails at the other end. The duplex part containing the recognition sites of the AR and NspI restriction endonuclease was immobilized on an Au electrode, whereas the single-stranded parts served as capture probes to activate the HCR. In the absence of the AR, NspI can cleave the duplex and release the capture probes, and thus, no HCR occurs. However, the AR can bind to the ARBP and protect the duplex from cleavage; therefore, the capture probes can trigger the HCR between four carefully designed G-quadruplex forming hairpin probes and the capture probes, resulting in the formation of numerous G-quadruplexes. Finally, differential pulse voltammetry (DPV) was carried out to quantify the AR. The assay revealed a detection limit of 7.64 fM. The verification of its high specificity and practicability in serum samples indicated its potential applications in the fields of clinical examination and disease diagnosis.


Asunto(s)
Técnicas Biosensibles/métodos , G-Cuádruplex , Técnicas de Amplificación de Ácido Nucleico/métodos , Hibridación de Ácido Nucleico/métodos , Receptores Androgénicos/sangre , Receptores Androgénicos/genética , Elementos de Respuesta , Enzimas de Restricción del ADN/metabolismo , Técnicas Electroquímicas , Electrodos , Oro , Humanos , Límite de Detección , Receptores Androgénicos/química
14.
Phys Chem Chem Phys ; 20(37): 24239-24249, 2018 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-30209481

RESUMEN

Recently, two-dimensional (2D) gallium nitride (GaN) was experimentally fabricated, and has promising applications in next-generation electronic and optoelectronic devices. A direct contact with metals to inject the carrier is often required for potential 2D GaN devices. Herein, the first systematic study on the interface properties of monolayer (ML) planar and buckled GaN with different metal electrodes (Al, Ti, Ag, Au, Sc, and Pt) in a field-effect transistor framework is presented using first-principles energy band calculations and quantum transport simulations. Because of moderate Fermi level pinning (electron pinning factor S = 0.63), ML planar GaN and the Ag electrode form an n-type lateral Schottky contact, while ML planar GaN and Ti, Al, and Au electrodes form a p-type lateral Schottky contact. The ML buckled GaN, Ag, Al, Ti, and Sc electrodes form a p-type lateral Schottky contact as a result of Fermi level pinning with a hole pinning factor of S = 0.75. Notably, a highly desirable n-type/p-type lateral ohmic contact is formed at the lateral interface of the ML planar GaN and Sc/Pt electrodes, and a p-type lateral ohmic contact is formed at the lateral interface of the ML buckled GaN and Pt/Au electrodes. Therefore, a low resistance contact can be realized in ML planar and buckled GaN devices.

15.
Chin J Integr Med ; 23(8): 617-624, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25967608

RESUMEN

OBJECTIVE: To elucidate the mechanism of Chinese tuina in treating sciatic nerve crush injury, and to detect the levels of tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1), which is thought to play an important role in nerve regeneration. METHODS: Thirty-two adult male Sprague-Dawley rats were subjected to sciatic nerve crush injury and 16 rats (sham-operated group) went through a sham operation. Control group was given no treatment while tuina group received tuina therapy since day 7 post-surgery. Tuina treatment was performed once a day and lasted for 20 days. The sciatic functional index was examined every 5 days during the treatment session. The rats' gastrocnemius muscles were evaluated for changes in mass and immunohistochemistry techniques were performed to detect the levels of tPA and PAI-1. RESULTS: Tuina therapy improved the motor function of sciatic nerve injured rats (P<0.05), however, it did not increase muscle volume (P<0.05). Tuina downregulated the levels of tPA and PAI-1 (P<0.05). CONCLUSIONS: The present study implies that tuina treatment could accelerate rehabilitation of peripheral nerve injury.


Asunto(s)
Regulación hacia Abajo , Medicina Tradicional China , Nervio Ciático/lesiones , Nervio Ciático/patología , Activador de Tejido Plasminógeno/metabolismo , Animales , Masculino , Músculos/patología , Compresión Nerviosa , Tamaño de los Órganos , Inhibidor 1 de Activador Plasminogénico/metabolismo , Ratas Sprague-Dawley
16.
Chin J Integr Med ; 23(12): 908-915, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27145942

RESUMEN

OBJECTIVE: To explore the protective effects of Tibetan medicine Zuo-Mu-A Decoction (, ZMAD) on the blood parameters and myocardium of high altitude polycythemia (HAPC) model rats. METHODS: Forty male Wistar rats were randomly divided into 4 groups by a random number table, including the normal, model, Rhodiola rosea L. (RRL) and ZMAD groups (10 in each group). Every group was raised in Lhasa to create a HAPC model except the normal group. After modeling, rats in the RRL and the ZMAD groups were administered intragastrically with RRL (20 mL/kg) and ZMAD (7.5 mL/kg) once a day for 2 months, respectively; for the normal and the model groups, 5 mL of distilled water was administered intragastrically instead of decoction. Then routine blood and hematologic rheology parameters were taken, levels of erythropoietin and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were tested, and ultrastructural change in the left ventricular myocardium was observed using transmission electron microscopy. RESULTS: Compared with the model group, ZMAD significantly reduced the red blood cell count, hemoglobin levels, whole blood viscosity at low/middle shear rates, plasma viscosity, erythrocyte electrophoretic time, erythropoietin and 8-OHdG levels, and also increased the erythrocyte deformation index (P<0.05). There was no difference in all results between the RRL and the ZMAD groups. The cardiac muscle fibers were well-protected, mitochondrial matrix swelled mildly and ultrastructure changes were less prominent in the ZMAD group compared with the model group. CONCLUSION: ZMAD has significant protective effects on the blood parameters against HAPC, and also has the beneficial effect in protecting against myocardial injury.


Asunto(s)
Mal de Altura/sangre , Mal de Altura/tratamiento farmacológico , Medicina Tradicional Tibetana , Miocardio/patología , Policitemia/sangre , Policitemia/tratamiento farmacológico , Sustancias Protectoras/uso terapéutico , 8-Hidroxi-2'-Desoxicoguanosina , Mal de Altura/complicaciones , Animales , Desoxiguanosina/análogos & derivados , Desoxiguanosina/sangre , Modelos Animales de Enfermedad , Eritropoyetina/sangre , Miocardio/ultraestructura , Policitemia/complicaciones , Sustancias Protectoras/farmacología , Reología/efectos de los fármacos
17.
Nanotechnology ; 19(31): 315302, 2008 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-21828783

RESUMEN

We demonstrate the fabrication of large scale nano- and micropatterned copper periodic structures on a silicon substrate without imposed templates. In the electrodeposition process, we employ a periodic variation voltage in an ultrathin layer of concentrated CuSO(4) electrolyte. The pattern can be controlled by varying the frequency of the applied potential. We suggest that the observed periodic micro-/nanostructures are caused by the lag of the migrating ion concentration profile versus the applied voltage profile near the tip of the growth.

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