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1.
Nanomaterials (Basel) ; 13(13)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37446501

RESUMO

In order to improve laser transmission efficiency at 1053 nm and 527 nm, a potassium deuterium phosphate (DKDP) crystal (a key component of high-power laser systems) needs a bi-layer antireflection coating system on its incident surface. UV-curable polysiloxane coatings with a refractive index varying from 1.500 to 1.485 were prepared through the polycondensation of a methacryloxy propyl trimethoxylsilane (MPS) monomer with a controllable degree of hydrolysis. Additionally, the influence rule of the coating structure on the refractive index was intensively studied, and the primary factors that dominate the hydrolysis process were discussed. Further refractive index adjustment was achieved using only a small amount of dopant based on the polysiloxane coating with refractive index of 1.485, allowing for high antireflection of the bi-layer coating system at desired wavelengths to be achieved. In addition, high laser damage resistance and remarkable mechanical properties of the coating were simultaneously realized through the incorporation of a minor quantity of dopants, which benefited from the successful modulation of the intrinsic refractive index of the polysiloxane coating.

2.
J Reprod Immunol ; 148: 103364, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34482001

RESUMO

Indoleamine 2, 3-dioxygenase (IDO), a tryptophan-catabolizing enzyme, is essential in physiological immunoregulation. The present research was conducted to elucidate the expression and roles of IDO in decidual macrophages (dMφ) during early pregnancy. Here, we observed a remarkable decrease of IDO+ dMφ from patients with unexplained recurrent spontaneous abortion (URSA). IDO+ dMφ displayed M2 phenotype with higher CD206, CD209 and CD163, and lower CD86. Interestingly, treatment with 1-methyl-d-tryptophan (1-MT, an IDO pathway inhibitor) led to the M1 bias of dMφ. Further analysis of the cytokine array and the qPCR showed decreased levels of trophoblast proliferation or invasion-related molecules (e.g., CXCL12 and BMP2) in 1-MT-treated dMφ. The data of co-culture system showed that 1-MT-pretreated dMφ decreased the proliferation and the expression of Ki-67 and Bcl-2, and increased cell apoptosis of HTR-8/Snveo cells. Additionally, the expression of IDO in U937 cells was up-regulated by decidual stromal cells (DSC) and HTR-8/Snveo cells in vitro, as well as estradiol and medroxyprogesterone. These data suggest that endocrine environment, DSC and trophoblasts should contribute to the high level of IDO in dMφ, and IDO+ dMφ with M2 dominant phenotype promote the survival of trophoblasts during early pregnancy. The abnormal lower level of IDO should trigger the dysfunction of dMφ, further suppress the survival of trophoblasts and increase the risk of miscarriage.


Assuntos
Aborto Espontâneo/imunologia , Decídua/imunologia , Macrófagos/imunologia , Gravidez/imunologia , Células Th2/imunologia , Trofoblastos/fisiologia , Apoptose , Diferenciação Celular , Proliferação de Células , Técnicas de Cocultura , Citocinas/metabolismo , Feminino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Recidiva , Células U937
3.
Curr Microbiol ; 77(1): 123-128, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31664502

RESUMO

Phage PA-YS35 is a novel lytic Pseudomonas aeruginosa phage belonging to the Myoviridae family and was isolated from the sewage of the First Hospital of Jilin University. The biological properties testing indicated that phage PA-YS35 is stable between - 20 and 60 °C and pH 4-9. The one-step growth curve shows that the latent period of PA-YS35 was 9 min, and the burst period was about 21 min by the size of approximately 380 progeny phages per host cell. The genome of phage PA-YS35 is linear double-stranded DNA with a size of 93,296 bp and a GC content of 49.35%. The results from RAST gene annotation analysis showed that the PA-YS35 genome contains 172 open reading frames (ORFs); the function of 41 ORFs can be predicted, whereas the product of remaining 131 ORFs are hypothetical proteins. According to phylogenetic tree of RNA ligase encoding sequence, phage PA-YS35 has a close evolutionary relationship with Pseudomonas phage PAK P1 because both of them are located on the same branch. The study of phage PA-YS35 genome will provide useful information for further research on the interaction between phages and their hosts.


Assuntos
Genoma Viral/genética , Fagos de Pseudomonas/genética , Composição de Bases/genética , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão , Fases de Leitura Aberta/genética , Filogenia
4.
Am J Reprod Immunol ; 83(2)2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31650642

RESUMO

PROBLEM: Decidual natural killer (dNK) cells play key roles in maternal-fetal immune regulation, trophoblast invasion, and vascular remodeling, and most dNK cell populations are CD56bright CD16- NK cells. However, the enrichment and redistribution of dNK cells in the local decidua have not been clarified yet. METHOD OF STUDY: A total of 45 women with normal pregnancies and 8 unexplained recurrent spontaneous abortion (RSA) patients were included. We isolated primary human dNK (n = 53) and peripheral blood NK (pNK) cells (n = 5) from specimen and analyzed CD56, CD82, and CD29 by flow cytometry (FCM). We assessed their adhesion ability by cell counts of NK cells adhered to decidual stromal cells (DSCs) in a co-culture system. RESULTS: We found that RSA patients had more CD56dim dNK cells with lower CD82 and higher CD29 than women with normal pregnancies. There were negative correlations of CD82 to CD29 on CD56dim and CD56+ dNK cells. In normal pregnancies, dNK cells had lower CD82 and higher CD29 expression with a stronger adhesion ability than pNK cells. Blocking CD82 on dNK cells increased the adhesive ability and CD29 expression, while blocking CD29 decreased the adhesive ability. Co-culturing dNK cells with trophoblast cells decreased CD82 expression and increased the adhesive ability of dNK cells and the percentage of CD56bright NK cells, while blocking trophoblast-derived CXCL12 increased CD82 expression, decreased CD29 expression, and impaired the adhesive ability of NK cells. CONCLUSION: Trophoblast cells enhance the adhesive ability of NK cells to DSCs via the CXCL12/CD82/CD29 signaling pathway and contribute to CD56bright NK cell enrichment in the uterus.


Assuntos
Quimiocina CXCL12/fisiologia , Decídua/imunologia , Células Matadoras Naturais/citologia , Trofoblastos/metabolismo , Aborto Habitual/imunologia , Adulto , Antígeno CD56/análise , Adesão Celular , Células Cultivadas , Técnicas de Cocultura , Decídua/citologia , Feminino , Idade Gestacional , Humanos , Imunofenotipagem , Integrina beta1/análise , Proteína Kangai-1/análise , Células Matadoras Naturais/química , Células Matadoras Naturais/classificação , Células Matadoras Naturais/imunologia , Contagem de Linfócitos , Gravidez , Células Estromais/citologia
5.
Ying Yong Sheng Tai Xue Bao ; 29(4): 1098-1106, 2018 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29726217

RESUMO

To examine the reproduction fitness coefficients and individual-level fitness of Toona ciliata var. pubescens, their sexual reproduction and natural regeneration were investigated during 2006-2016, with four natural populations in Jiulianshan National Reserve as test objects. The results showed that there were only 2-10 trees for the natural populations of T. ciliata var. pubescens with a small initial number of fruiting plants (3-9 trees), which were from the initial fruiting plants or their first/second generation. The sexual reproduction of these isolated populations were significantly different, and their seed production capacities tended to decline over time. With the maturing of communities, soil seed banks and seed germinations were extremely poor, and the number of trees that could be growing to mature stage was nearly zero. The optimum maturity age of T. ciliata var. pubescens was about 40 a, and the fitness coefficients (2.0-2.8) rapidly increased in early development stage, but then was sharply reduced (0.3-0.5), and then gradually dropped to almost 0. There were significant differences in the fitness at individual level (0-14 tree·cm-2) among different populations, but their values were low (close to zero). Based on the existing reproduction rate, the actual values of sexual reproduction and regeneration fitness were much lower than the predicted ones. Due to the low level of genetic fitness, the sexual reproductive ability of different populations all showed decreasing trends. The natural sexual regeneration ability tended to decline, while the fitness of T. ciliata var. pubescens further decreased. All those factors suggested higher investment risks. Therefore, the systems of sexual reproduction became unbalanced and deteriorating. We proposed that more studies, including breeding mating, pollination, seed setting, and genetic diversity evaluation, are needed. Moreover, we should provide suitable forest environment through cleaning up litter in the fruiting stage and applying appropriate thinning during the transition period from seedling to young tree growth.


Assuntos
Aptidão Genética , Meliaceae , Reprodução , Cruzamento , Variação Genética , Polinização , Plântula , Sementes , Árvores
6.
Ying Yong Sheng Tai Xue Bao ; 23(4): 972-8, 2012 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-22803462

RESUMO

Taking the natural Toona ciliata var. pubescens forest in the Jiujiangshan National Nature Reserve in Jiangxi Province of China as test object, an investigation was conducted on the seed rain, soil seed bank, and seedlings number in 2008-2011. The seed rain of the forest was dispersed from late October to the end of December. In 2010, the seed rain intensity in different sampling plots was in the order of Xiagongtang observatory (320.3 +/- 23.5 seeds x m(-2)) > Xiagongtang protection station (284.7 +/- 24.2 seeds x m(-2)) > Daqiutian protection station (251.6 +/- 24.7 seeds x m(-2)), and the quantity of the intact seeds in soil supplied for seed germination and regeneration was 222.0, 34.3, and 22.6 seeds x m(-2), respectively. The seed bank reserves was affected by the seed production amount, bird feeding, and seed viability, etc., of which, bird feeding was the prime factor for the substantial drop of the seed bank reserves. Due to the low resistance against storage and a large number of rot during storage, the seeds in soil could hardly be effectively stored beyond one month. The seedlings germinated in December were averagely less than 2 stands x m(-2), and the soil seed reserves in the next January was the least (6.7-11.8 seeds x m(-2)), with the germinated seedlings averagely 0.4-0.6 stands x m(-2), which was consistent with the rare distribution of natural seedlings in the forest. It was concluded that the small seed rain reserves, low seed vigor of soil seed bank, and low seedling establishment were the important factors impacting the natural regeneration of T. ciliata var. pubescens.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Meliaceae/crescimento & desenvolvimento , Dispersão de Sementes , Sementes/crescimento & desenvolvimento , China , Chuva , Plântula/crescimento & desenvolvimento
7.
Bing Du Xue Bao ; 24(4): 295-9, 2008 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-18780633

RESUMO

To explore the role of lipid raft in assembly of human herpesvirus 6, the HHV-6 GS strain was applied to infect the HSB2 cells and then the lipid raft composition was extracted from the cells with non-ionic detergent Triton-X 100. The relationship between the HHV-6 envelope glycoprotein and lipid raft was analyzed by Western Blot. Immunofluorescence double-staining was used to study the colocalization of the HHV-6 glycoprotein B(gB) with GPI anchored protein CD59 and ganglioside GM respectively. HHV-6 envelope glycoprotein B, H, L, Q1 and Q2 (gB, gH, gL, gQ1 and gQ2) were all existed in the lipid raft. Moreover, CD59 and HHV-6 envelope glycoprotein B showed the same localization through the confocal microscope. We concluded the lipid raft provided the platform for HHV-6 assembly. This is the first report concerning to the role of lipid raft in assembly of human Herpesvirus 6.


Assuntos
Herpesvirus Humano 6/fisiologia , Microdomínios da Membrana/fisiologia , Montagem de Vírus , Antígenos CD59/análise , Imunofluorescência , Gangliosídeo G(M1)/análise , Proteínas do Envelope Viral/análise
8.
J Virol ; 76(13): 6750-61, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12050388

RESUMO

Human herpesvirus 6 (HHV-6) is a lymphotropic betaherpesvirus that productively infects T cells and monocytes. HHV-6 isolates can be differentiated into two groups, variants A and B (HHV-6A and HHV-6B). Here, we show a functional difference between HHV-6A and -6B in that HHV-6A induced syncytium formation of diverse human cells but HHV-6B did not. The syncytium formation induced by HHV-6A was observed 2 h after infection; moreover, it was found in the presence of cycloheximide, indicating that HHV-6A induced fusion from without (FFWO) in the target cells. Furthermore, the fusion event was dependent on the expression of the HHV-6 entry receptor, CD46, on the target cell membrane. In addition, we determined that short consensus repeat 2 (SCR2), -3, and -4 of the CD46 ectodomain were essential for the formation of the virus-induced syncytia. Monoclonal antibodies against glycoproteins B and H of HHV-6A inhibited the fusion event, indicating that the syncytium formation induced by HHV-6A required glycoproteins H and B. These findings suggest that FFWO, which HHV-6A induced in a variety of cell lines, may play an important role in the pathogenesis of HHV-6A, not only in lymphocytes but also in various tissues, because CD46 is expressed ubiquitously in human tissues.


Assuntos
Antígenos CD/metabolismo , Células Gigantes/fisiologia , Herpesvirus Humano 6/patogenicidade , Glicoproteínas de Membrana/metabolismo , Receptores Virais/metabolismo , Animais , Antígenos CD/química , Antígenos CD/genética , Fusão Celular , Linhagem Celular , Chlorocebus aethiops , Cricetinae , Herpesvirus Humano 6/classificação , Herpesvirus Humano 6/genética , Humanos , Proteína Cofatora de Membrana , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Células Vero , Proteínas do Envelope Viral/metabolismo
9.
J Gen Virol ; 83(Pt 4): 847-854, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11907335

RESUMO

The characterization is reported of the human herpesvirus-6B (HHV-6B) rep/U94 gene, which is a homologue of the adeno-associated virus type 2 rep. In this study, a monoclonal antibody was produced against HHV-6B REP (anti-REP mAb). Immunofluorescence staining using the anti-REP mAb showed that REP was localized to the nucleus in HHV-6-infected MT4 cells. It was first detected at 24 h post-infection (p.i.) and accumulated to higher levels by 72 h p.i. REP may be expressed only at very low levels in HHV-6-infected cells: even when the late protein glycoprotein H was detected in nearly 90% of HHV-6-infected cells, REP was detected in only a small percentage of them. Western blot analysis showed that the anti-REP mAb recognized a 56-kDa polypeptide in HHV-6B-infected MT4 cells. Furthermore, the REP protein was shown to bind single-stranded DNA.


Assuntos
DNA Helicases/metabolismo , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA , Herpesvirus Humano 6/genética , Transativadores/metabolismo , Animais , Western Blotting , DNA Helicases/genética , Fases de Leitura Aberta , Biossíntese de Proteínas , Spodoptera , Transativadores/genética
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