De Novo Design of Antimicrobial Peptides With a Special Charge Pattern and Their Application in Combating Plant Pathogens.

Plant diseases are important issues in agriculture, and the development of effective and environment-friendly means of disease control is crucial and highly desired. Antimicrobial peptides (AMPs) are known as potential alternatives to chemical pesticides because of their potent broad-spectrum antimicrobial activity and because they have no risk, or have only a low risk, of developing chemical-resistant pathogens. In this study, we designed a series of amphipathic helical peptides with different spatial distributions of positive charges and found that the peptides that had a special sequence pattern "BBHBBHHBBH" ("B" for basic residue and "H" for hydrophobic residue) displayed excellent bactericidal and fungicidal activities in a wide range of economically important plant pathogens. The peptides with higher helical propensity had lower antimicrobial activity. When we modified the peptides with a long acyl chain at their N-terminus, their plant protection effect improved. Our application of the fatty acyl-modified peptides on the leaves of tomato and Arabidopsis plants lessened the infection caused by Pectobacterium carotovorum subsp. carotovorum and Botrytis cinerea. Our study provides important insights on the development of more potent novel AMPs for plant protection.

Dexmedetomidine protects against lung injury induced by limb ischemia-reperfusion via the TLR4/MyD88/NF-κB pathway.

Dexmedetomidine (DEX) can protect the lung from ischemia-reperfusion (I/R) injury, but the underlying mechanisms are not fully understood. The aims of this study were to determine whether DEX attenuates lung injury following lower extremity I/R and to investigate the related toll-like receptor 4 (TLR4) signaling pathway. Twenty-eight SD rats were divided into four groups (n = 7): Sham, I/R, I/R + DEX (25 µg/kg prior to ischemia), and I/R + DEX + Atip (250 µg/kg atipamezole before DEX treatment). Lower extremity I/R was induced by left femoral artery clamping for 3 hours and followed by 2 hours reperfusion. Quantitative alveolar damage and the wet/dry (W/D) ratio were calculated. Interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-α in the bronchoalveolar lavage fluid (BALF) and serum and myeloperoxidase (MPO) in the lung were measured. The TLR4 and MyD88 mRNA expression levels were measured by RT-PCR, nuclear factor (NF)-κB, and phosphorylated NF-κB by western blot, respectively. Quantitative alveolar damage, W/D ratio, MPO, BALF and serum IL-1, IL-6, and TNF-α, and TLR4, MyD88, NF-κB, and p-NF-κB expression significantly increased in the I/R group relative to the Sham group. DEX preconditioning significantly reduced lung edema, and histological injury relative to the I/R group. Serum and BALF IL-1, IL-6, and TNF-α levels, MPO activity and TLR4, MyD88, NF-κB, and p-NF-κB expression were also significantly reduced in the I/R + DEX group compared with the I/R group. Atipamezole partially reversed all the aforementioned effects. DEX preconditioning protects the lungs against lower extremity I/R injury via α2-adrenoceptor-dependent and α2-adrenoceptor-independent mechanisms. It also suppresses the TLR4 pathway and reduces inflammation.

Comparison of periarticular anesthesia with liposomal bupivacaine with femoral nerve block for pain control after total knee arthroplasty: A PRISMA-compliant meta-analysis.

BACKGROUND: Periarticular anesthesia (PAI) with liposomal bupivacaine (LB) and femoral nerve block (FNB) were 2 common type of pain management after total knee arthroplasty (TKA). There is no consensus about PAI with LB shows better clinical outcome than FNB. Thus, we performed a systematic review and meta-analysis to compare the efficacy and safety of PAI with LB and FNB for patients prepared for TKA. METHODS: Randomized controlled trials (RCTs) and non-RCTs from PubMed (1966-2017.2), EMBASE (1980-2017.2), and the Cochrane Central Register of Controlled Trials (CENTRAL, 2017.2), Web of Science (1966-2017.2), and Chinese Wanfang database (1980-2017.2) were searched. Continuous outcomes including visual analogue scale (VAS) at 24, 48, and 72 hours, total morphine consumption, length of hospital, and range of motion (ROM) were reported as the weighted mean difference with 95% and confidence interval (CI) and discontinuous outcomes (the occurrence of postoperative nausea and vomiting [PONV]) were presented as relative risk with 95% CI. Random-effects model was adopted to analyze the relevant data. RESULTS: According to the inclusion and exclusion criteria, 8 studies with 2407 patients were eligible and finally included in this meta-analysis (LB = 1114, FNB = 1293). There was no significant difference between VAS at 24, 4, and 72 hours, ROM, and the occurrence of PONV between PAI with LB group versus FNB group (P > 0.05). Compared with the FNB group, PAI with LB was associated with a significant decrease in length of hospital stay by 0.43 day (MD = -0.43; 95% CI -0.60 to -0.27; P = 0.001) and the total dose of total morphine consumption by (MD = -29.32; 95% CI -57.55 to -1.09; P = 0.042). CONCLUSIONS: The review of trials found that PAI with LB provided a significant beneficial effect over FNB in improving the pain or decreased the total morphine consumption in patients who underwent TKA. However, PAI with LB associated with less LOS than FNB. More high quality RCTs are still needed to identify the effects and optimal dose of LB for pain management after TKA.