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Superhydrophobic ZnO nanorods coatings with a strong adhesive force to the surface (rose petal effect) or a low sliding angle (lotus leaf effect) were fabricated on the zinc plate by the hydrothermal plus sol-gel method. The corrosion resistance and durability of the superhydrophobic coatings in 5 wt% NaCl solution were investigated. The coating with loose ZnO nanostructure on ZnO nanorods shows a high adhesive force to water with low corrosion resistance, while the coating with a layer of dense nanotubes on nanorods exhibits a low adhesive to water with a high corrosion resistance due to a layer of trapped air among micro/nanostructures, which can delay the penetration of corrosive media. It can be found that the nanorods coating with lotus leaf effect lost its superhydrophobicity after 5150 s immersion in salt solution and the water repellency model is transformed from Cassie state to Wenzel state.
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OBJECTIVE: To verify the effect of the mutant gene vps4b on the expression of tooth development-related proteins, dentin sialophosphoprotein (DSPP) and collagenâ (COL-â ). METHODS: Paraffin tissue sections of the first molar tooth germ were obtained from the heads of fetal mice at the embryonic stages of 13.5, 14.5, and 16.5 days and from the mandibles of larvae aged 2.5 and 7 days after birth. The immunohistochemical method was used to detect the expression and location of DSPP and COL-â in wild-type mouse and vps4b knockout mouse. RESULTS: DSPP and COL-â were not found in the bud and cap stages of wild-type mouse molar germ. In the bell stage, DSPP was positively expressed in the inner enamel epithelium and dental papilla, whereas COL-â was strongly expressed in the dental papilla and dental follicle. During the secretory and mineralized periods, DSPP and COL-â were intensely observed in ameloblasts, odontoblasts, and dental follicles, but COL-â was also expressed in the dental papilla. After vps4b gene knockout, DSPP was not expressed in the dental papilla of the bell stage and in the dental papilla and dental follicle of the secretory phase. The expression position of COL-â in the bell and mineralization phase was consistent with that in the wild-type mice. Moreover, the expression of COL-â in the dental papilla changed in the secretory stage. CONCLUSIONS: Gene vps4b plays a significant role in the development of tooth germ. The expression of DSPP and COL-â may be controlled by gene vps4b and regulates the development of tooth dentin and cementum together with vps4b.
Assuntos
ATPases Associadas a Diversas Atividades Celulares , Complexos Endossomais de Distribuição Requeridos para Transporte , Proteínas da Matriz Extracelular , Fosfoproteínas , Sialoglicoproteínas , ATPases Associadas a Diversas Atividades Celulares/genética , Animais , Colágeno/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Proteínas da Matriz Extracelular/metabolismo , Camundongos , Camundongos Knockout , Dente Molar , Odontoblastos , Fosfoproteínas/metabolismo , Sialoglicoproteínas/metabolismo , Germe de DenteRESUMO
BACKGROUND: Prone position ventilation (PPV) is an important strategy for patients with severe acute respiratory distress syndrome (ARDS). This prospective study investigated the use of electromyography of the diaphragm (EMGdi) for monitoring respiratory drive in patients with moderate to severe ARDS during long-term PPV. METHODS: An integrated nostril-gastric feeding tube containing an esophageal electrode and balloon was placed in 14 patients with severe ARDS prior to PPV. EMGdi and trans-pulmonary pressure (∆PL) data were collected before PPV (baseline), every 2 h during PPV, and 2 h after the restoration of supine position ventilation (post-2 h SPV). RESULTS: In ARDS patients, the static compliance of the chest wall was significantly decreased after PPV. EMGdi levels were slightly lower in the early, middle, and late stages of PPV compared with baseline. Patients who received neuromuscular blocker experienced a greater drop in EMGdi from baseline than those who did not. CONCLUSIONS: For ARDS patients, EMGdi was slightly decreased after prolonged PPV. This is contrary to the change in diaphragm electromyography during normal body position changes. Monitoring EMGdi regularly during PPV in ARDS patients is feasible and can be used as a reference for lung protective ventilation strategies.
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BACKGROUND: Protein arginine methylation is a prevalent post-translational modification. The protein arginine methyltransferase family (PRMT) is involved in many cellular processes in eukaryotes, including transcriptional regulation, epigenetic regulation, RNA metabolism, and DNA damage repair. Toxoplasma gondii, an opportunistic protozoan parasite, encodes five conserved PRMTs. PRMT5 is thought to be responsible for substantial PRMT activity in T. gondii; however, it has not yet been characterized. METHODS: We tagged the 3' end of the endogenous TgPRMT5 genomic locus with sequence encoding a 3X hemagglutinin (HA) epitope. IFA and WB were performed to check the expression and subcellular localization of TgPRMT5 in tachyzoites and bradyzoites. In vitro methylation assays were performed to determine whether endogenous TgPRMT5 has arginine methyltransferase activity. RESULTS: IFA and WB results showed that T. gondii PRMT5 (TgPRMT5) was localized in the cytoplasm in the tachyzoite stage; however, it shifts largely to the nuclear compartment in the bradyzoite stage. The in vitro methylation showed that TgPRMT5 has authentic type II PRMT activity and forms monomethylarginines and symmetric dimethylarginines. CONCLUSIONS: We determined the expression and cellular localization of TgPRMT5 in tachyzoites and bradyzoites and confirmed its type II PRMT activity. We demonstrated the major changes in expression and cellular localization of TgPRMT5 during the tachyzoite and bradyzoite stages in T. gondii. Our findings suggest that TgPRMT5 protein may be involved in tachyzoite-bradyzoite transformation.
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Proteína-Arginina N-Metiltransferases/genética , Toxoplasma/enzimologia , Toxoplasma/genética , Citoplasma/química , Epigênese Genética , Estágios do Ciclo de Vida , Metilação , Proteína-Arginina N-Metiltransferases/metabolismoRESUMO
BACKGROUND: Toxoplasma gondii is one of the most important apicomplexan parasites and infects one-third of the human population worldwide. Transformation between the tachyzoite and bradyzoite stages in the intermediate host is central to chronic infection and life-long risk. There have been some transcriptome studies on T. gondii; however, we are still early in our understanding of the kinds and levels of gene expression that occur during the conversion between stages. RESULTS: We used high-throughput RNA-sequencing data to assemble transcripts using genome-based and de novo strategies. The expression-level analysis of 6996 T. gondii genes showed that over half (3986) were significantly differentially expressed during stage conversion, whereas 2205 genes were upregulated, and 1778 genes were downregulated in tachyzoites compared with bradyzoites. Several important gene families were expressed at relatively high levels. Comprehensive functional annotation and gene ontology analysis revealed that stress response-related genes are important for survival of bradyzoites in immune-competent hosts. We compared Trinity-based de novo and genome-based strategies, and found that the de novo assembly strategy compensated for the defects of the genome-based strategy by filtering out several transcripts with low expression or those unannotated on the genome. We also found some inaccuracies in the ToxoDB gene models. In addition, our analysis revealed that alternative splicing can be differentially regulated in response to life-cycle change. In depth analysis revealed a 20-nt, AG-rich sequence, alternative splicing locus from alt_acceptor motif search in tachyzoite. CONCLUSION: This study represents the first large-scale effort to sequence the transcriptome of bradyzoites from T. gondii tissue cysts. Our data provide a comparative view of the tachyzoite and bradyzoite transcriptomes to allow a more complete dissection of all the molecular regulation mechanisms during stage conversions. A better understanding of the processes regulating stage conversion may guide targeted interventions to disrupt the transmission of T. gondii.
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Estágios do Ciclo de Vida/genética , Proteínas de Protozoários/genética , Toxoplasma/genética , Transcriptoma , Processamento Alternativo/genética , Animais , Perfilação da Expressão Gênica/métodos , Genoma de Protozoário , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estágios do Ciclo de Vida/fisiologia , Análise de Sequência de RNA , Toxoplasma/fisiologia , Toxoplasmose Animal/parasitologiaRESUMO
OBJECTIVES: To evaluate the efficacy of percutaneous aspiration thrombectomy (PAT) for infrainguinal arterial thromboembolism in patients undergoing endovascular recanalization (EVR) and to investigate the predictors for thromboembolic complications. MATERIALS AND METHODS: In total, 23 patients (23 limbs) who underwent PAT for thromboembolism (PAT group, PG) during EVR and 237 patients (302 limbs) who underwent successful EVR without thromboembolic complications (control group, CG) were enrolled. Immediate post-operation and follow-up outcomes were compared between the two groups. Multivariate analysis was performed to identify the predictors of thromboembolic complications. Technical success of PAT was defined as achievement of <30% residual stenosis and restoration of mTIMI grade 3. RESULTS: The technical success rate was 95.7% in PG. After intervention, the ankle-brachial index (ABI), restoration of blood flow and improvement in dorsal/plantar arterial pulse score showed no significant differences between PG and CG. During follow-up in PG, a sustained ABI improvement was observed in 63.6% (70.9% in CG), an improvement in walking distance in 68.8% (79.9% in CG,), ulcer healing in 75.0% (71.7% in CG) and restenosis/occlusion in 31.8% (25.2% in CG). The limb salvage rate was 100% in PG (96.0% in CG), and pain relief was observed in 66.7% patients with critical limb ischaemia (81.6% in CG). Superficial femoral artery involvement [0.233; 95% confidence interval (CI), 0.108-0.461; P < 0.001], de-novo lesion occlusion (683.8; 95% CI, 36.5-12804.6; P < 0.001) and intraluminal angioplasty (118.4; 95% CI, 8.0-1758.0; P = 0.001) was associated with high incidence of thromboembolism. CONCLUSION: PAT is a safe and effective treatment for thromboembolism during infrainguinal arterial EVR. SFA involvement, de-novo lesion occlusion and intraluminal angioplasty may be predictors of thromboembolic complications.