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1.
Opt Express ; 32(6): 10479-10489, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571258

RESUMO

We demonstrate an efficient active Q-switched Ho:GdVO4 self-Raman laser at 2500 nm for the first time, to our knowledge. Using Ho:GdVO4 crystal as the gain medium for both the 2048nm fundamental laser and the 2500 nm Raman laser, the output performances of a new mid-infrared self-Raman laser were investigated. The maximum average output power of 1.45 W was achieved at an incident pump power of 22.5 W, with a slope efficiency of 25.8%, for an output transmittance of 30% and a pulse repetition frequency of 15 kHz. The maximum single pulse energy of 96.7 µJ with a pulse width of 11.35 ns was obtained, corresponding to the peak power of 8.5 kW. The beam quality was near diffraction limited with the M2 factors of 1.15 and 1.06 along the x and y directions. Moreover, adopting the two-end output way of the fundamental laser and the Raman laser, the Raman gain coefficient of Ho:GdVO4 crystal was estimated to be 1.14 cm/GW at 2048nm. This work shows that Ho:GdVO4 is an excellent self-Raman laser crystal for the generation of high power Raman laser at 2.5 µm.

2.
Animals (Basel) ; 14(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38539922

RESUMO

Transport stress can cause damage to animals. In this experiment, 60 four-month-old lambs were randomly divided into three groups: CG (basal diet), EG (basal diet + 375 mg/d/lamb electrolytic multivitamin), and NG (basal diet + 200 mg/d/lamb neomycin). The results were as follows: during road transport, in all groups, the levels of SOD, T-AOC, and GSP-Px, and mRNA expressions of CAT, SOD, Nrf2, HO-1, and Bcl-2 in the jejunum and colon decreased (p < 0.01). However, mRNA expressions of Keap1, IL-1ß, IL-2, IL-12, Bax, and Caspase3 in the jejunum and colon and the level of MDA increased (p < 0.01). The concentrations of IgA, IgG, and sIgA in the jejunum and colon also decreased (p < 0.01). In the EG and NG, the levels of SOD (p < 0.05) and T-AOC (p < 0.01) increased, and the level of MDA decreased (p < 0.01). However, in the jejunum, the levels of SOD and T-AOC, the concentrations of IgA and IgG, and mRNA expression of Bcl-2 increased (p < 0.05). mRNA expressions of IL-1, IL-2, and Caspase 3 (p < 0.05), and mRNA expression of IL-12 (p < 0.01) decreased. In the colon, SOD activity and the concentration of sIgA increased (p < 0.01). The level of MDA and mRNA expressions of IL-2 and Caspase 3 also decreased (p < 0.05). In the jejunum and colon, mRNA expression of SOD (p < 0.05) and mRNA expression of Nrf2 increased (p < 0.01). mRNA expression of Keap1 (p < 0.05) and Bax (p < 0.01) decreased. In summary, road transport can cause a decrease in antioxidant activity and immunity of lambs and an increase in oxidative damage. Electrolytic multivitamins and neomycin can improve immune function and potentially reduce oxidative damage to the jejunum and colon.

3.
J Environ Manage ; 352: 119995, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38183918

RESUMO

This paper aims to examine the impact of geopolitical risk (GPR), threats (GPT) and acts (GPA) on returns and volatilities of regional climate change stocks under different market conditions, employing quantile regressions. Our main results suggest that climate change stock returns positively (negatively) respond to GPR in bullish (bearish) market states, however the effect is not uniform across the regions. The volatilities mainly show a positive response to geopolitical tensions; geopolitical acts appear to have a more pronounced impact on volatilities than geopolitical threats. We further find that GPR leads to higher volatility during the Russia-Ukraine war, creating heightened uncertainty. Overall, the results reveal that geopolitical risks have an asymmetric and heterogenous impact on climate change stocks. The results provide significant insights and implications for financial market participants and policy makers.


Assuntos
Mudança Climática , Humanos , Federação Russa , Incerteza
4.
Animals (Basel) ; 14(2)2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38254346

RESUMO

Animals experience stress when they are transported. In this experiment, sixty 4-month-old lambs were randomly divided into three groups: CG (basal diet), EG (basal diet + 375 mg/d/lamb electrolytic multivitamin) and NG (basal diet + 200 mg/d/lamb neomycin). The transportation day was recorded as the 0th day. Blood, liver, spleen, jejunum and colon were collected on the 0th, 7th and 14th day. The results were as follows: In EG and NG groups, the lamb weights (p < 0.01), IgA and IgG (p < 0.05) increased significantly. The concentrations of ACTH, E, COR, IL-1ß, IL-6 and IFN-γ decreased significantly (p < 0.01). The content of colonic propionate increased significantly (p < 0.05). The villus height and V/C increased, and crypt depth decreased significantly (p < 0.01). The mRNA expressions of Occludin and MUC1, and the protein expression of Occludin in the jejunal mucosa, the mRNA expressions of ZO-1 and Occludin, and the protein expression in the colonic mucosa increased significantly (p < 0.01). The mRNA expression of TRAF6 and the protein expression of TLR4 in the jejunum decreased significantly (p < 0.05), as well as the mRNA expressions of TLR4, MyD88 and NF-kB, and the protein expression of NF-kB p65 and the mRNA expressions of TRAF6, TLR4 and NF-kB in the colon (p < 0.01). In conclusion, an electrolytic multivitamin could potentially improve the immunity and intestinal barrier function, and when it was added with 375 mg/d in the basal diet for each lamb from 2 d before transportation to 7 d after transportation, it had a better effect than neomycin.

5.
Opt Lett ; 48(13): 3495-3498, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37390164

RESUMO

A dual-wavelength passively Q-switched Ho:GdVO4 self-Raman laser in the 2.5 µm wave band was demonstrated with Cr:ZnS as a saturable absorber. Synchronized dual-wavelength pulsed laser outputs at 2473 nm and 2520 nm were acquired, corresponding to Raman frequency shifts of 808 cm-1 and 883 cm-1, respectively. The maximum total average output power of 114.9 mW was obtained at an incident pump power of 12.8 W with a pulse repetition rate of 3.57 kHz and a pulse width of 16.36 ns. The maximum total single pulse energy was 32.18 µJ, corresponding to a total peak power of 1.97 kW. The power ratios of the two Raman lasers can be controlled by varying the incident pump power. To the best of our knowledge, this is the first time a dual-wavelength passively Q-switched self-Raman laser in the 2.5 µm wave band has been reported.


Assuntos
Lasers , Frequência Cardíaca
6.
Proc Natl Acad Sci U S A ; 117(40): 24837-24848, 2020 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-32963095

RESUMO

The vertebrate inner ear, responsible for hearing and balance, is able to sense minute mechanical stimuli originating from an extraordinarily broad range of sound frequencies and intensities or from head movements. Integral to these processes is the tip-link protein complex, which conveys force to open the inner-ear transduction channels that mediate sensory perception. Protocadherin-15 and cadherin-23, two atypically large cadherins with 11 and 27 extracellular cadherin (EC) repeats, are involved in deafness and balance disorders and assemble as parallel homodimers that interact to form the tip link. Here we report the X-ray crystal structure of a protocadherin-15 + cadherin-23 heterotetrameric complex at 2.9-Å resolution, depicting a parallel homodimer of protocadherin-15 EC1-3 molecules forming an antiparallel complex with two cadherin-23 EC1-2 molecules. In addition, we report structures for 10 protocadherin-15 fragments used to build complete high-resolution models of the monomeric protocadherin-15 ectodomain. Molecular dynamics simulations and validated crystal contacts are used to propose models for the complete extracellular protocadherin-15 parallel homodimer and the tip-link bond. Steered molecular dynamics simulations of these models suggest conditions in which a structurally diverse and multimodal protocadherin-15 ectodomain can act as a stiff or soft gating spring. These results reveal the structural determinants of tip-link-mediated inner-ear sensory perception and elucidate protocadherin-15's structural and adhesive properties relevant in disease.


Assuntos
Percepção Auditiva , Caderinas/química , Caderinas/metabolismo , Proteínas Relacionadas a Caderinas , Caderinas/genética , Dimerização , Orelha Interna/metabolismo , Audição , Humanos , Simulação de Dinâmica Molecular , Equilíbrio Postural , Ligação Proteica , Conformação Proteica , Domínios Proteicos
7.
Zhongguo Zhong Yao Za Zhi ; 44(10): 2072-2077, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31355563

RESUMO

Paclitaxel( PTX) is used as a broad spectrum anti-tumor medicine. However,serious drawbacks restrict clinical application of PTX. In this study,we prepared tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier containing paclitaxel( BSALC/DOPE-PTX) to study the effective antitumor activity. The in vivo targeting ability of the nanocarrier in tumor bearing nude mice was evaluated by using a Kodak in vivo imaging system FX PRO. The in vivo anti-tumor activity was evaluated in MDA-MB-231 tumor bearing mice,and representative sections were stained with hematoxylin and eosin( H&E),and examined by light microscopy. The results showed that DiR-loaded FA-BSA-LC/DOPE selectively targeted tumor,and had a relatively long residence in the tumor tissue. According to the in vivo anti-tumor activity study,FA-BSA-LC/DOPE-PTX exhibited an outstanding tumor inhibition effect with a tumor growth inhibition rate of 79.3%,and tumor tissue sections stained by hematoxylin and eosin( HE) showed severe necrosis areas and many dead cells with condensed nuclei in the FA-BSA-LC/DOPE-PTX group. Therefore,FA-BSA-LC/DOPE-PTX is a biocompatible,tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier,with a very marked anti-tumor activity in tumor-bearing mice in vivo.


Assuntos
Portadores de Fármacos , Lipoproteínas , Nanopartículas , Neoplasias Experimentais/tratamento farmacológico , Paclitaxel/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus
8.
Structure ; 26(9): 1210-1225.e4, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30033219

RESUMO

Cadherin-23 (CDH23) is an essential component of hair-cell tip links, fine filaments that mediate inner-ear mechanotransduction. The extracellular domain of CDH23 forms about three-fourths of the tip link with 27 extracellular cadherin (EC) repeats that are structurally similar but not identical to each other. Calcium (Ca2+) coordination at the EC linker regions is key for tip-link elasticity and function. There are ∼116 sites in CDH23 affected by deafness-causing mutations, many of which alter conserved Ca2+-binding residues. Here we present crystal structures showing 18 CDH23 EC repeats, including the most and least conserved, a fragment carrying disease mutations, and EC repeats with non-canonical Ca2+-binding motif sequences and unusual secondary structure. Complementary experiments show deafness mutations' effects on stability and affinity for Ca2+. Additionally, a model of nine contiguous CDH23 EC repeats reveals helicity and potential parallel dimerization faces. Overall, our studies provide detailed structural insight into CDH23 function in mechanotransduction.


Assuntos
Caderinas/química , Caderinas/metabolismo , Perda Auditiva Neurossensorial/genética , Mutação de Sentido Incorreto , Animais , Proteínas Relacionadas a Caderinas , Caderinas/genética , Cálcio/metabolismo , Cristalografia por Raios X , Perda Auditiva Neurossensorial/metabolismo , Humanos , Mecanotransdução Celular , Camundongos , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína
9.
Int J Pharm ; 480(1-2): 116-27, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25615984

RESUMO

In the present study, we constructed a tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier containing paclitaxel (FA-BSA-LC/DOPE-PTX), by adding 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) and oleic acid as pH-sensitive components into the formulation of lipid core and then coating with folic acid modified bovine serum albumin (FA-BSA) for tumor targeting activity. In vitro drug release study demonstrated that paclitaxel (PTX) was released from FA-BSA-LC/DOPE in a pH-dependent manner. The vitro cytotoxicity assays showed that all the blank nanocarriers were nontoxic. However, MTT assay showed that FA-BSA-LC/DOPE-PTX was highly cytotoxic. Cellular uptake experiments analyzed with flow cytometry and laser scan confocal microscope (LSCM) revealed that FA-BSA-LC/DOPE was taken up in great amount via folate receptor-mediated endocytosis and pH-sensitive release of drug to cytoplasm. Furthermore, the study of intracellular drug release behavior demonstrated that the FA-BSA-LC/DOPE escaped from lysosomes and released drug into cytoplasm. The in vivo targeting activity showed that the nanocarrier selectively targeted tumor and had long residence time for BSA layer increased the stability in blood. Moreover, FA-BSA-LC/DOPE-PTX produced very marked anti-tumor activity in tumor-bearing mice in vivo. Therefore, FA-BSA-LC/DOPE as biocompatible, tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier is a promising system for effective intracellular delivery of PTX to tumor.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Paclitaxel/administração & dosagem , Animais , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Citoplasma/metabolismo , Portadores de Fármacos/química , Feminino , Ácido Fólico/química , Humanos , Concentração de Íons de Hidrogênio , Lipídeos/química , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ácido Oleico/química , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Fosfatidiletanolaminas/química , Soroalbumina Bovina/química
10.
J Drug Target ; 23(4): 311-22, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25539074

RESUMO

In the present study, we devised a strategy that paclitaxel (PTX) with lipid and octadecylamine were prepared to lipid nanoparticle (PTX-LNP) with positive charge, folic acid-modified bovine serum albumin (FB)-coated surface of PTX-LNP through electrostatic attraction and generated the lipoprotein-mimicking nanocomplex (FB-PTX-LNP) for dual-targeting therapy. Bovine serum albumin (BSA) was used as the protein model due to its specific targeting to tumor by increased transendothelial gp60-mediated transport and increased intratumoral accumulation as a result of the secreted protein, acidic and rich in cysteine (SPARC)-albumin interaction. The further conjugating folic acid to BSA achieved the dual active targeting. In vitro cytotoxicity tests suggested FB-PTX-LNP and BSA-PTX-LNP exhibited significantly higher cytotoxic activity against MCF-7 and HepG2 cells compared to PTX-LNP. The cellular uptake experiments indicated that FB-coumarin-6-LNP modified with dual-targeting had a faster and greater cellular uptake when compared to BSA-coumarin-6-LNP and coumarin-6-LNP by MCF-7 cells. Thus, both BSA and FA did play roles in in vitro cytotoxicity and cellular uptake. Furthermore, the targeting ability and therapeutic efficacy of FB-PTX-LNP were assessed in vivo. FB-PTX-LNP produced very marked targeting ability and anti-tumor activity in MDA-MB-231 tumor-bearing mice. These results indicate the protein-lipid nanocomplex FB-PTX-LNP is a potential nanocarrier for Paclitaxel dual-targeting to tumor.


Assuntos
Sistemas de Liberação de Medicamentos , Lipoproteínas/química , Nanopartículas , Paclitaxel/administração & dosagem , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Transporte Biológico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Feminino , Ácido Fólico/química , Células Hep G2 , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Paclitaxel/farmacocinética , Paclitaxel/farmacologia , Soroalbumina Bovina/química , Soroalbumina Bovina/farmacocinética , Sialoglicoproteínas/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-24110384

RESUMO

In the present study, we developed a mental switch-based asynchronous brain-computer interface for 2D cursor control. Two mental switches were designed: one was to switch from non-intentional to intentional control state, and the other one for conducting the reverse process. 2D control and mental switches are all based on three-class motor imagery. With four subjects participating in the study, the experimental results demonstrated the efficiency of the proposed asynchronous 2D control strategy.


Assuntos
Interfaces Cérebro-Computador , Adulto , Humanos , Imagens, Psicoterapia , Masculino , Probabilidade , Fatores de Tempo , Adulto Jovem
12.
Zhong Yao Cai ; 34(9): 1373-6, 2011 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-22260004

RESUMO

OBJECTIVE: To explore the correlation between microscopic characteristics constant of Honeysuckle and its chemical component. METHODS: Capacity analysis was used to assay the number of pollen grain and non-glandular hair of Honeysuckle powder and the content of chlorogenic acid was determined by HPLC. RESULTS: In Honeysuckle, the microscopic characteristic constants of pollen grain and non-glandular hairs and chlorogenic acid content were significantly correlated. CONCLUSION: Determination of the microscopic characteristics of pollen grain and non-glandular hair constant value can be used as a means of quality control.


Assuntos
Ácido Clorogênico/análise , Lonicera/química , Lonicera/ultraestrutura , Plantas Medicinais/química , Pólen/ultraestrutura , Cromatografia Líquida de Alta Pressão , Flores/química , Flores/ultraestrutura , Pós , Controle de Qualidade
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