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1.
Nanotechnology ; 34(17)2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36645911

RESUMO

Sensitive detection of nucleolin (NCL) is of great significance for the early diagnosis of cancer. In this work, as a new type of two-dimensional (2D) transition metal dichalcogenides (TMDCs), TaS2nanoflakes (NFs) were precisely constructed by atomic layer deposition (ALD) on carbon fiber paper (CFP) with high specific surface area.In situobservation showed that the nucleation and growth of TaS2nanoflakes were precisely controlled by the number of ALD cycles, thereby regulating their electrochemical properties. The electrochemical performance of TaS2NFs was observed in depth, and compared with that of traditional 2D TMDCs. Due to the high surface area and conductivity, anodic/cathodic current of ∼1570µA of TaS2NFs/CFP can be obtained. Subsequently, an electrochemical biosensor based on ALD-constructed TaS2NFs/CFP for cancer-related NCL detection was fabricated. Due to the excellent electrochemical performance of TaS2NFs/CFP, ultrasensitive detection of NCL in the linear range of 0.1 pM-10 nM with a detection limit of 0.034 pM was achieved.


Assuntos
Neoplasias , Fosfoproteínas , Proteínas de Ligação a RNA , Fibra de Carbono , Condutividade Elétrica , Neoplasias/diagnóstico , Nucleolina
2.
Nanotechnology ; 32(17): 175602, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33461182

RESUMO

Although it suffers from a heavy dependence on the noble platinum catalyst, the electrochemical hydrogen evolution reaction (HER) is one of the most promising methods for the production of hydrogen. After numerous efforts, it is found that MoS2-based heterostructure may replace platinum as the electrochemical HER catalyst. In this work, the nanocrystalline NiSe2/MoS2 heterostructures were successfully prepared on the carbon fiber paper (CFP) substrate through electrochemical deposition and hydrothermal process. According to a series of electrochemical HER tests and a comparison with other MoS2-based heterostructure catalysts, the CFP/NiSe2/MoS2 catalyst with an overpotential η 10 of 143 mV and a Tafel slope of 45 mV dec-1 exhibited an excellent electrochemical HER catalytic performance and durability. In addition, CFP/NiSe2/MoS2 catalyst was treated by plasma to further improve the catalytic performance of the catalyst.

3.
J Lipid Res ; 60(2): 341-352, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30504232

RESUMO

To elucidate the transcriptomic changes of long noncoding RNAs (lncRNAs) in high-fat diet (HFD)-fed mice, we defined their hepatic transcriptome by RNA sequencing. Aberrant expression of 37 representative lncRNAs and 254 protein-coding RNAs was observed in the livers of HFD-fed mice with insulin resistance compared with the livers from control mice. Of these, 24 lncRNAs and 179 protein-coding RNAs were upregulated, whereas 13 lncRNAs and 75 protein-coding RNAs were downregulated. Functional analyses showed that the aberrantly expressed protein-coding RNAs were enriched in various lipid metabolic processes and in the insulin signaling pathway. Genomic juxtaposition and coexpression patterns identified six pairs of aberrantly expressed lncRNAs and protein-coding genes, consisting of five lncRNAs and five protein-coding genes. Four of these protein-coding genes are targeted genes upregulated by PPARα. As expected, the corresponding lncRNAs were significantly elevated in AML12 cells treated with palmitic acid or the PPARα agonist, WY14643. In Hepa1-6 cells, knockdown of NONMMUG027912 increased the cellular cholesterol level, the expression of cholesterol biosynthesis genes and proteins, and the HMG-CoA reductase activity. This genome-wide profiling of lncRNAs in HFD-fed mice reveals one lncRNA, NONMMUG027912, which is potentially regulated by PPARα and is implicated in the process of cholesterol biosynthesis.


Assuntos
Colesterol/metabolismo , Dieta Hiperlipídica/efeitos adversos , Perfilação da Expressão Gênica , Fígado/efeitos dos fármacos , Fígado/metabolismo , RNA Longo não Codificante/genética , Animais , Linhagem Celular , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
4.
Langmuir ; 35(10): 3651-3657, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30777760

RESUMO

Solid lubricating films are usually applied to reduce friction and adhesion of micro-/nano-electromechanical systems (MEMS/NEMS). Due to the special structure, MoS2 is endowed with excellent lubricity. Layer-controlled ultrathin MoS2 films with strong interactions to the underlying substrates were prepared by atomic layer deposition (ALD) using MoCl5 and H2S and characterized by various measures. Nanotribological properties of the MoS2 films with different thicknesses were observed by an atomic force microscope tip under various loads. In the initial stage of ALD, bigger roughness induced by discontinuous nanoparticles can increase friction. However, when the number of ALD cycles is more than 3, the friction force can be effectively reduced by about 40-55% because of interlayer sliding and lower adhesion. Finally, friction properties against sliding velocities of the MoS2 films were also observed. The ultrathin MoS2 film obtained by ALD exhibits a huge application value as reducing friction surface in MEMS/NEMS.

5.
Nanotechnology ; 30(9): 095402, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30523970

RESUMO

Electrochemical water splitting into H2 and O2 has attracted wide attention owing to the urgent need for clean and renewable energy sources. However, the scarcity and high-cost limit the large-scale application of noble metal catalysts such as IrO2 and RuO2. In this work, as a low-cost catalyst for the electrochemical O2 evolution reaction (OER), MoS2 nanoflakes were obtained by atomic layer deposition (ALD) using MoCl5 and H2S on carbon fiber paper surface. According to the results of electrochemical measurements, the MoS2 nanoflakes exhibit an excellent catalytic activity, and the activity can be modulated by controlling the density and the internal resistance of MoS2 nanoflakes. Moreover, the plasma treatment can further improve the activity of MoS2 nanoflakes, and the reason was discussed through the measurements of contact angle, electrochemical impedance spectroscopy, and electrochemically active surface area. The MoS2 nanoflakes obtained by ALD possess huge values for electrochemical OER as a catalyst.

6.
Nanotechnology ; 28(19): 195605, 2017 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-28323252

RESUMO

Monolayer and/or atomically thin transition metal dichalcogenides cover a wide range of two-dimensional (2D) materials, whose fascinating semiconducting and optical properties have made them promising candidate materials for optoelectronic devices. Controllable growth of these materials is critical for their device applications. By using MoCl5 and H2S as precursors, monolayer and ultrathin molybdenum disulfide (MoS2) films with controlled lamellar structure have been directly built layer by layer on SiO2 substrates without being followed by high-temperature annealing. Furthermore, the thickness of MoS2 films can be precisely regulated by applying different atomic layer deposition (ALD) cycles. Once an ALD cycle is applied, one molecular layer of MoS2 material will be 'added' on the substrate or original existing MoS2 films. At the initial stage (one to three ALD cycles), the density of MoS2 materials increases with an increase in ALD cycles, while a large area of continuous MoS2 film on the substrate can be obtained when four or more ALD cycles are applied. In this way, excellent triangular crystals of MoS2 with controlled atomic size in thickness and a highly oriented hexagonal crystal structures can be obtained by applying definite ALD cycles.

7.
Mol Cytogenet ; 17(1): 13, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38764094

RESUMO

BACKGROUND: The incidence of spontaneous abortion (SA), which affects approximately 15-20% of pregnancies, is the most common complication of early pregnancy. Pathogenic copy number variations (CNVs) are recognized as potential genetic causes of SA. However, CNVs of variants of uncertain significance (VOUS) have been identified in products of conceptions (POCs), and their correlation with SA remains uncertain. RESULTS: Of 189 spontaneous abortion cases, trisomy 16 was the most common numerical chromosome abnormality, followed by monosomy X. CNVs most often occurred on chromosomes 4 and 8. Gene Ontology and signaling pathway analysis revealed significant enrichment of genes related to nervous system development, transmembrane transport, cell adhesion, and structural components of chromatin. Furthermore, genes within the VOUS CNVs were screened by integrating human placental expression profiles, PhyloP scores, and Residual Variance Intolerance Score (RVIS) percentiles to identify potential candidate genes associated with spontaneous abortion. Fourteen potential candidate genes (LZTR1, TSHZ1, AMIGO2, H1-4, H2BC4, H2AC7, H3C8, H4C3, H3C6, PHKG2, PRR14, RNF40, SRCAP, ZNF629) were identified. Variations in LZTR1, TSHZ1, and H4C3 may contribute to embryonic lethality. CONCLUSIONS: CNV sequencing (CNV-seq) analysis is an effective technique for detecting chromosomal abnormalities in POCs and identifying potential candidate genes for SA.

8.
Sci Total Environ ; 947: 174605, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38997030

RESUMO

Sixty-nine total suspended particle (TSP) samples, paired with forty-eight surface soil samples, covering four seasons from January 2021 to November 2021, were collected from the Three Gorges Reservoir Region (TGRR). Twenty per- and poly-fluoroalkyl substances (PFASs) were analyzed to evaluate their contamination characteristics and understand the role of atmospheric deposition on the environmental loads in TGRR. The annual average concentrations of PFASs in TSP and soil were 37.2 ± 1.22 pg·m-3 and 0.798 ± 0.134 ng·g-1, respectively. For TSP, concentrations were highest in spring and lowest in summer. For soil, it was in autumn and winter, respectively. The seasonality was more influenced by anthropogenic activities than by meteorological conditions or physicochemical parameters of the soil. Positive matrix fractionation (PMF) indicated that, based on annual averages, PFOA-based products (40.2 %) were the major sources of PFASs in TSP, followed by PFOS-based products (25.2 %) and precursor degradation (34.6 %). The highest source contributor for PFASs in spring was precursor degradation (40.9 %), while in other three seasons, it was PFOA-based products (39.9 %, 40.9 % and 52.0 %, respectively). The mean atmospheric dry and wet deposition fluxes of PFASs were estimated at 4.38 ng·m-2·day-1 and 23.5 ng·m-2·day-1, respectively. The contribution of atmospheric deposition to the inventory mass of PFASs in the surface soil was 22.3 %. These findings fill a gap in knowledge regarding the processes and mechanisms of the occurrence, sources and atmospheric deposition of PFASs in the TGRR.

9.
Nanoscale Adv ; 5(3): 830-839, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36756515

RESUMO

The sensitive detection of cardiac troponin I (cTnI) is of great significance for the early diagnosis of acute myocardial infarction (AMI). Herein, in order to fabricate an electrochemical biosensor for ultrasensitive cTnI detection, atomic layer deposition (ALD) was employed to directly deposit NbS2 nanoflakes (NFs) on carbon fiber paper (CFP). Due to the self-limiting reaction of ALD, NbS2NFs were deposited uniformly and accurately on the surface of carbon fibers by controlling the number of ALD cycles, which ensured ultrasensitive detection. Precise regulation of the nanoscale morphology and electrochemical performance of NbS2 nanoflakes via ALD cycles was observed in depth. Owing to the high surface area and conductivity, an anodic/cathodic current of ∼3.01 mA of NbS2NFs/CFP can be obtained. Subsequently, an electrochemical biosensor based on the excellent performance of NbS2NFs/CFP was fabricated. The ultrasensitive detection of cTnI in a linear range of 1 fM to 0.1 nM with a detection limit of 0.32 fM was achieved.

10.
Mol Genet Genomic Med ; 11(2): e2100, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36370055

RESUMO

BACKGROUND: Nance-Horan syndrome (NHS) is a rare and often overlooked X-linked dominant disorder characterized by dense congenital cataracts, dental abnormalities, and mental retardation. The majority of NHS variations include frameshift mutations, nonsense mutations, microdeletions, and insertions. METHODS: Copy number variation sequencing was performed to determine the microdeletion. The expression of NHS was detected by RT-PCR. Four family members were tested for X chromosome inactivation. RESULTS: In this study, all members were examined for systemic examinations and genetic testing of four members and two affected subjects are observed. We identified a heterozygous microdeletion of -0.52 Mb at Xp22.13 in a female proband presenting NHS phenotypically. The microdeletion contains the REPS2 and NHS genes and was inherited from a phenotypically normal mother. Of interest, the expression NHS of proband was reduced and the skewed X chromosome inactivation rate reached more than 85% compared with her mother and the control. It was concluded that the haploinsufficiency of the NHS gene may account for the majority of clinical symptoms in the affected subjects. The variability among female carriers presumably results from nonrandom X chromosome inactivation. CONCLUSION: Our findings broaden the spectrum of NHS mutations and provide molecular insight into NHS clinical prenatal genetic diagnosis.


Assuntos
Catarata , Variações do Número de Cópias de DNA , Humanos , Feminino , Linhagem , Inativação do Cromossomo X , Proteínas Nucleares/genética , Proteínas de Membrana/genética , Catarata/genética , Proteínas de Ligação ao Cálcio/genética
11.
Front Plant Sci ; 13: 880125, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35712602

RESUMO

Plant growth-promoting rhizobacteria have been shown to play important roles in maintaining host fitness under periods of abiotic stress, and yet their effect on mulberry trees which regularly suffer drought after flooding in the hydro-fluctuation belt of the Three Gorges Reservoir Region in China remains largely uncharacterized. In the present study, 74 bacterial isolates were obtained from the rhizosphere soil of mulberry after drought stress, including 12 phosphate-solubilizing and 10 indole-3-acetic-acid-producing isolates. Bacillus megaterium HGS7 was selected for further study due to the abundance of traits that might benefit plants. Genomic analysis revealed that strain HGS7 possessed multiple genes that contributed to plant growth promotion, stress tolerance enhancement, and antimicrobial compound production. B. megaterium HGS7 consistently exhibited antagonistic activity against phytopathogens and strong tolerance to abiotic stress in vitro. Moreover, this strain stimulated mulberry seed germination and seedling growth. It may also induce the production of proline and antioxidant enzymes in mulberry trees to enhance drought tolerance and accelerate growth recovery after drought stress. The knowledge of the interactions between rhizobacteria HGS7 and its host plant might provide a potential strategy to enhance the drought tolerance of mulberry trees in a hydro-fluctuation belt.

12.
RSC Adv ; 11(43): 26928-26936, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-35479997

RESUMO

Although MoS2 has shown its potential as an electro-catalyst for the oxygen evolution reaction (OER), its research is still insufficient. In this study, as a novel MoS2-based heterostructure electro-catalyst for OER, namely NiSe2@MoS2 nano-heterostructure, was constructed on a carbon fiber paper (CFP) substrate by a simple approach, which includes electrochemical deposition of NiSe2 film and hydrothermal processing of MoS2 film. In addition to a series of observations on the material structure, electrocatalytic OER performance of NiSe2@MoS2 was fully evaluated and further compared with other MoS2-based OER electro-catalysts. It exhibits an outstanding catalytic performance with an overpotential η 10 of 267 mV and a Tafel slope of 85 mV dec-1. Only 6% loss of current density before and after 10 h indicates its excellent durability. The results indicate that the obtained NiSe2@MoS2 is an excellent OER electro-catalyst and worth exploring as a substitute for noble metal-based materials.

13.
Front Genet ; 12: 715437, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707637

RESUMO

BACKGROUND: Tyrosinase-positive oculocutaneous albinism (OCA, type II, OCA2) is an autosomal recessive genetic disease in which the biosynthesis of melanin decreases in the skin, hair, and eyes. OCA2 disease is caused by mutations in OCA2 gene. The gene product plays a role in regulating the pH of melanosomes. Up to now, hundreds of OCA2 mutations have been reported and novel variants are still being discovered. METHODS: In this study, we reviewed the records of OCA2 patients who had conducted albinism genetic testing, and then analyzed the clinical and genetic information of 28 OCA2 patients who had been genetically diagnosed by using Sanger sequencing and next-generation sequencing. RESULTS: In this study, we reported 31 variants screened from 28 Chinese OCA2 families, and characterized the detailed molecular and clinical presentations. There were 12 novel variants among all detected variants, including 3 missense variants (p.G393V, p.T482A, and p.R720P), 4 frameshift variants (p.R53Gfs∗49, p.N279Kfs∗17, p.I469Lfs∗4, p.I655Nfs∗12), 2 splicing variants (c.1637-2A > G, c.1951 + 1G > C), 2 stopgain variants (p.L278X, p.W652X) and 1 insertion variants (p.P315LinsT). One potential cluster of missense variants was implicated indicating the important roles of the underlying domains in OCA2 pathogenesis. CONCLUSION: Our results were beneficial for diagnosis and precision clinical management for OCA2-related disorder, and this study expanded the mutation spectrum of oculocutaneous albinism.

14.
Ying Yong Sheng Tai Xue Bao ; 31(5): 1682-1690, 2020 May.
Artigo em Zh | MEDLINE | ID: mdl-32530247

RESUMO

The analysis of biodiversity spatial patterns and the detection of hotspots are effective ways for conservation planning and scientific management of biodiversity. Based on field investigation, historical data and literature information, we constructed the comprehensive index of biodiversity by considering habitat quality, species diversity and landscape diversity within Chongqing Pengxi River Wetland Nature Reserve. Combined with spatial autocorrelation analysis, we analyzed spatial distribution pattern and the degree of spatial autocorrelation of biodiversity in the nature reserve, identified biodiversity hotspots, and discussed the protection effectiveness of existing nature reserve for the hotspots. The results showed that the spatial pattern of biodiversity in the nature reserve tended to decrease with the increases of distance from the river and riparian zone. Areas with high value of biodiversity index were mainly concentrated in Pengxi River, Puli River, Baijiaxi Stream and alongshore areas. There was significant positive correlation in the spatial distribution of biodiversity. The spatial autocorrelation of local areas was mainly characterized by high-high aggregation and low-low aggregation. The area of biodiversity hotspots was 457 hm2, accounting for 11.1% of the total nature reserve. The core area of current nature reserve covered 51% of the hotspots and 50% of the secondary hotspots. The structure and functional zone distribution of nature reserve should be further optimized and adjusted. We suggested that other hotspots should become part of the core area, including the Longwangtang area of Puli River, Xiaoyakou, Dengjiawan, Dongziyan, Longwangtang, Jiuwuju, Huatouju, Xinpuzi and Longjia yard of Baijiaxi Stream. The cold spots should be removed from the core area, to improve the function zoning of nature reserve. Our results could provide quantitative basic references for the boundary optimization and control zoning of nature reserve, and the reasonable promotion of the adjustment of "three zones to two zones", and could have guiding significance for improving effectiveness of species conservation and formulating scientific protection strategies.


Assuntos
Rios , Áreas Alagadas , Biodiversidade , China , Conservação dos Recursos Naturais , Ecossistema
15.
Nat Commun ; 11(1): 2293, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385249

RESUMO

The sodium channels Nav1.7, Nav1.8 and Nav1.9 are critical for pain perception in peripheral nociceptors. Loss of function of Nav1.7 leads to congenital insensitivity to pain in humans. Here we show that the spider peptide toxin called HpTx1, first identified as an inhibitor of Kv4.2, restores nociception in Nav1.7 knockout (Nav1.7-KO) mice by enhancing the excitability of dorsal root ganglion neurons. HpTx1 inhibits Nav1.7 and activates Nav1.9 but does not affect Nav1.8. This toxin produces pain in wild-type (WT) and Nav1.7-KO mice, and attenuates nociception in Nav1.9-KO mice, but has no effect in Nav1.8-KO mice. These data indicate that HpTx1-induced hypersensitivity is mediated by Nav1.9 activation and offers pharmacological insight into the relationship of the three Nav channels in pain signalling.


Assuntos
Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Ativação do Canal Iônico , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.9/metabolismo , Peptídeos/efeitos adversos , Venenos de Aranha/efeitos adversos , Sequência de Aminoácidos , Animais , Feminino , Gânglios Espinais/patologia , Humanos , Hiperalgesia/complicações , Masculino , Camundongos Knockout , Canal de Sódio Disparado por Voltagem NAV1.7/química , Canal de Sódio Disparado por Voltagem NAV1.8/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.9/química , Neurônios/efeitos dos fármacos , Neurônios/patologia , Dor/complicações , Dor/fisiopatologia , Ratos
16.
ACS Omega ; 3(3): 3120-3128, 2018 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-31458572

RESUMO

Nowadays, with the rapid development of environmental protection awareness, the demand for the emergence of a green counterpart of lubricant additive plays a more and more important role in reducing friction and wear as the times require. In this paper, full-hollow and semihollow molybdenum disulfide (MoS2) microspheres were prepared via a hydrothermal method and were characterized and confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). According to our results, both fully hollow and semihollow MoS2 microspheres possessed excellent lubrication-enhancing effects for liquid paraffin (LP), while full-hollow samples after friction provided better photocatalytic degradation properties than semihollow samples after friction. Related analysis indicated that curved layer opened structures with more rim and edge sites, bigger surface area, and narrower band gap made full-hollow MoS2 samples achieve a better photocatalytic level. Thus, it was a sustainable solution for both lubrication-enhancing and photocatalytic degradation functions during different stages of the usage of lubricating oils, which suggests a potential strategy for achieving environmentally friendly developments.

17.
Theranostics ; 7(12): 3168-3178, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28839471

RESUMO

Cell penetrating peptides (CPPs) are commonly utilized for intracellular delivery of functional materials to circumvent biomembrane barrier. However, further application of CPPs is hindered by lacking selectivity toward targeted cells. The spider venom peptide, lycosin-I, is a CPP with potent cytotoxicity to cancer cells, which might enable lycosin-I to deliver functional materials into cancer cells selectively. In this study, we demonstrated that the lycosin-I-conjugated spherical gold nanoparticles (LGNPs) not only exhibited efficient cellular internalization efficiency toward cancer cells but also displayed unprecedented selectivity over noncancerous cells. Although LGNPs were removed from the living circulatory system via reticuloendothelial system-dominant clearance modes without noticeable adverse effects to animals, they actually displayed active tumor-targeting effects and efficient accumulation in tumors in vivo. Furthermore, the potential application of this platform for cancer therapy was explored by lycosin-I-conjugated gold nanorods (LGNRs). LGNRs exhibited selective intracellular translocation towards cancer cells and efficient photothermal effect under near infrared (NIR, 808 nm) irradiation, which consequently killed cancer cells in vitro and in vivo effectively. Therefore, the established LGNPs and LGNRs possessed great potential in cancer-targeting delivery and photothermal therapy.


Assuntos
Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma/tratamento farmacológico , Ouro/administração & dosagem , Nanopartículas Metálicas/administração & dosagem , Venenos de Aranha/administração & dosagem , Animais , Peptídeos Catiônicos Antimicrobianos/metabolismo , Antineoplásicos/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Xenoenxertos , Humanos , Camundongos Endogâmicos BALB C , Modelos Teóricos , Transplante de Neoplasias , Ligação Proteica , Venenos de Aranha/metabolismo , Resultado do Tratamento
18.
Toxicon ; 125: 44-49, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27867092

RESUMO

Heteropoda venatoria is a venomous spider species distributed worldwide and has a characteristic habit of feeding on insects. Reverse-phase high-performance liquid chromatography and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry analyses revealed that H. venatoria venom contains hundreds of peptides with a predominant molecular weights of 3000-5000 Da. Intra-abdominal injection of the venom had severe toxic effects on cockroaches and caused death at higher concentrations. The LD50 was 28.18 µg/g of body weight in the cockroach. It was found that the venom had potent inhibitory effect on voltage-gated sodium channels (VGSCs) in Periplaneta americana cockroach dorsal unpaired median (DUM) neurons with an IC50 values of 6.25 ± 0.02 µg/mL. However, 100 µg/mL venom only partially blocked VGSC currents in rat dorsal root ganglion cells, a much lower inhibitory effect than that on DUM VGSCs. Our results indicate that the venom of H. venatoria contains diverse neurotoxins that might become new leads for bioinsecticides.


Assuntos
Proteínas de Artrópodes/farmacologia , Proteínas de Insetos/antagonistas & inibidores , Venenos de Aranha/farmacologia , Aranhas , Bloqueadores do Canal de Sódio Disparado por Voltagem/farmacologia , Animais , Proteínas de Artrópodes/química , Cromatografia Líquida de Alta Pressão , Baratas/efeitos dos fármacos , Dose Letal Mediana , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Venenos de Aranha/química , Bloqueadores do Canal de Sódio Disparado por Voltagem/química
19.
IEEE Trans Vis Comput Graph ; 22(5): 1568-79, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27045912

RESUMO

In order to deliver information effectively, virtual human demonstrators must be able to address complex spatial constraints and at the same time replicate motion coordination patterns observed in human-human interactions. We introduce in this paper a whole-body motion planning and synthesis framework that coordinates locomotion, body positioning, action execution and gaze behavior for generic demonstration tasks among obstacles. Human-like solutions are achieved with a coordination model extracted from experiments with human subjects. Given an observer location and a target demonstration to be performed, the proposed planner automatically identifies body placements respecting visibility constraints, locomotion accessibility, and action feasibility among obstacles. Actions are modeled with clusters of example motions and a fast collision avoidance procedure in blending space is introduced to avoid nearby obstacles when needed. Locomotion towards new placements integrates planning among obstacles and is based on a motion capture database organized for efficient synthesis of motions with precise path following and arrival constraints. The proposed solution introduces effective approaches for modeling and solving complex demonstrative tasks for interactive applications.


Assuntos
Gráficos por Computador , Simulação por Computador , Relações Interpessoais , Interface Usuário-Computador , Gestos , Humanos , Locomoção , Modelos Teóricos
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