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1.
通过测定5-唑烷氮氧自由基硬脂酸(5-DSA)标记裸鼠皮肤角质层的ESR谱,研究离子导入法与渗透促进剂100%月桂氮酮(100%AZ)、5%月桂氨 酮/丙二醇溶液(5% AZ/PG)和10%油酸/丙二醇溶液(10%OA/PG)并用对裸鼠皮肤角质层的影响。离子导入法处理皮肤后,标记物序参数降低,各向同性超精细分裂偶合常数增大,表明低密度电流能够引起皮肤角质层细胞间脂质排列有序性降低,流动性增大,极性增大;离子导入法与渗透促进剂并用处理皮肤后,序参数进一步降低,各向同性超精细分裂偶合常数进一步增大,表明二者对皮肤角质层的影响具有协同作用。  相似文献   
2.
Potassium ion hybrid capacitors have great potential for large‐scale energy devices, because of the high power density and low cost. However, their practical applications are hindered by their low energy density, as well as electrolyte decomposition and collector corrosion at high potential in potassium bis(fluoro‐sulfonyl)imide‐based electrolyte. Therefore, anode materials with high capacity, a suitable voltage platform, and stability become a key factor. Here, N‐doping carbon‐coated FeSe2 clusters are demonstrated as the anode material for a hybrid capacitor, delivering a reversible capacity of 295 mAh g?1 at 100 mA g?1 over 100 cycles and a high rate capability of 158 mAh g?1 at 2000 mA g?1 over 2000 cycles. Meanwhile, through density functional theory calculations, in situ X‐ray diffraction, and ex situ transmission electron microscopy, the evolution of FeSe2 to Fe3Se4 for the electrochemical reaction mechanism is successfully revealed. The battery‐supercapacitor hybrid using commercial activated carbon as the cathode and FeSe2/N‐C as the anode is obtained. It delivers a high energy density of 230 Wh kg?1 and a power density of 920 W kg?1 (the energy density and power density are calculated based on the total mass of active materials in the anode and cathode).  相似文献   
3.
The jasmonic acid (JA) pathway plays crucial roles in plant defence against pathogens and herbivores. Rice stripe virus (RSV) is the type member of the genus Tenuivirus. It is transmitted by the small brown planthopper (SBPH) and causes damaging epidemics in East Asia. The role(s) that JA may play in the tripartite interaction against RSV, its host, and vector are poorly understood. Here, we found that the JA pathway was induced by RSV infection and played a defence role against RSV. The coat protein (CP) was the major viral component responsible for inducing the JA pathway. Methyl jasmonate treatment attracted SBPHs to feed on rice plants while a JA-deficient mutant was less attractive than wild-type rice. SBPHs showed an obvious preference for feeding on transgenic rice lines expressing RSV CP. Our results demonstrate that CP is an inducer of the JA pathway that activates plant defence against RSV while also attracting SBPHs to feed and benefitting viral transmission. This is the first report of the function of JA in the tripartite interaction between RSV, its host, and its vector.  相似文献   
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Replication of RNA viruses in insect cells triggers an antiviral defense that is mediated by RNA interference (RNAi) which generates viral-derived small interfering RNAs (siRNAs). However, it is not known whether an antiviral RNAi response is also induced in insects by reoviruses, whose double-stranded RNA genome replication is thought to occur within core particles. Deep sequencing of small RNAs showed that when the small brown planthopper (Laodelphax striatellus) was infected by Rice black-streaked dwarf virus (RBSDV) (Reoviridae; Fijivirus), more viral-derived siRNAs accumulated than when the vector insect was infected by Rice stripe virus (RSV), a negative single-stranded RNA virus. RBSDV siRNAs were predominantly 21 and 22 nucleotides long and there were almost equal numbers of positive and negative sense. RBSDV siRNAs were frequently generated from hotspots in the 5′- and 3′-terminal regions of viral genome segments but these hotspots were not associated with any predicted RNA secondary structures. Under laboratory condition, L. striatellus can be infected simultaneously with RBSDV and RSV. Double infection enhanced the accumulation of particular genome segments but not viral coat protein of RBSDV and correlated with an increase in the abundance of siRNAs derived from RBSDV. The results of this study suggest that reovirus replication in its insect vector potentially induces an RNAi-mediated antiviral response.  相似文献   
6.
Qin  Jinglin  Zhang  Jing  Shi  Minglan  Xi  Liyan  Zhang  Junmin 《Mycopathologia》2020,185(3):467-476
Background

Chromoblastomycosis is a chronic, progressive fungal disease of the skin and subcutaneous tissue caused by a unique group of dematiaceous fungi. Fonsecaea monophora, a new species distinct from Fonsecaea pedrosoi strains, is the main pathogen responsible for chromoblastomycosis in south China. Macrophages can be polarized into two categories: classically activated and alternatively activated.

Objectives

Little is known about the relationship between F. monophora and macrophage polarization. This study aimed to study the effect of F. monophora on the polarization of THP-1 cells to macrophages.

Methods

We established coculture systems of F. monophora and THP-1-derived macrophages in different activation states.

Results

F. monophora enhanced the phagocytosis by macrophages in the initially activated state and weakened the phagocytosis by classically activated macrophages without affecting that by alternatively activated macrophages. Classically activated macrophages had the strongest killing effect on F. monophora, while the initially activated macrophages had the weakest. The pathogen could not be rapidly cleared by any type of macrophage. F. monophora promoted the expression of proinflammatory cytokines and inhibited that of anti-inflammatory cytokines.

Conclusions

F. monophora promoted the polarization of THP-1 cells to classically activated macrophages and inhibited that of THP-1 cells to alternatively activated macrophages.

  相似文献   
7.
Chromoblastomycosis is one of the most frequent chronic infections caused by melanized fungi. In order to evaluate the clinical characteristics of chromoblastomycosis in Mainland China, we performed an evidence-based review of published literature. PubMed and Chinese-language database of CNKI, VIP and Wanfang data during January 1990–August 2011 were searched. Epidemiology, clinical features, laboratory findings, therapy and prognosis were analyzed. Cladophialophora carrionii was the most common causative agent in the north of the Mainland China, and Fonsecaea monophora and F. pedrosoi were the most common agents in the southern part of the Mainland China. Infection commonly initiated after the etiologic agents gain entrance through puncture wounds and more common involved extremities of the males. Skin lesions were found in different sites, like the extremities, buttocks, trunk and face, and presented diversity morphology. There were about seven different clinical types found in Mainland China: plaque type, tumoral type, cicatricial type, verrucous type, pseudo-vacuole type, eczymatous type and mixed type of lesions. The success of treatment for chromoblastomycosis was related to the causative agent, the clinical form and severity of the lesions. Most of the patients could be treated successfully with the physical treatment, chemotherapy and/or combination therapy. The itraconazole, terbinafine or a combination of both were commonly medication for these mycosis patients. Physical methods were usually indicated to support chemotherapy with some severe forms and long-lasting cases. Photodynamic therapy has been extended from the oncological field to that of antimicrobial chemotherapy in these years. We applied it on some recalcitrant cases of chromoblastomycosis and found its good clinical response, and hopeful it could be a promising therapy in near future.  相似文献   
8.
To minimize the side effect of chemotherapy, a novel reduction/pH dual-sensitive drug nanocarrier, based on PEGylated dithiodipropionate dihydrazide (TPH)-modified hyaluronic acid (PEG-SS-HA copolymer), was developed for targeted delivery of doxorubicin (DOX) to hepatocellular carcinoma. The copolymer was synthesized by reductive amination via Schiff's base formation between TPH-modified HA and galactosamine-conjugated poly(ethylene glycol) aldehyde/methoxy poly(ethylene glycol) aldehyde. Conjugation of DOX to PEG-SS-HA copolymer was accomplished through the hydrazone linkage formed between DOX and PEG-SS-HA, and confirmed by FTIR and 1H NMR spectra. The polymer–DOX conjugate could self-assemble into spherical nanoparticles (∼150 nm), as indicated by TEM and DLS. In vitro release studies showed that the DOX-loaded nanoparticles could release DOX rapidly under the intracellular levels of pH and glutathiose. Cellular uptake experiments demonstrated that the nanoparticles could be efficiently internalized by HepG2 cells. These results indicate that the PEG-SS-HA copolymer holds great potential for targeted intracellular delivery of DOX.  相似文献   
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Highlights? Yeast Hsp70 SSB binds cotranslationally to a defined set of nascent polypeptides ? SSB shows specificity for substrates highly challenged in cotranslational folding ? The heterodimeric cochaperone RAC modulates cotranslational SSB specificity ? Loss of SSB function leads to widespread misfolding and aggregation  相似文献   
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