Porcine reproductive and respiratory syndrome (PRRS), caused by the porcine reproductive and respiratory syndrome virus (PRRSV), is one of the major diseases threatening the swine industry. This study aims to rationally design and optimize natural antimicrobial peptides to identify antiviral candidates with potent inhibitory activity against PRRSV, thereby establishing a foundation for the development of novel preventive and therapeutic agents targeting PRRS. In this study, with cecropin D (CD) as the parent peptide, three derivatives (CD-2, CD-3, and CD-4) were designed through amino acid substitutions. CD and derived peptides were obtained by solid-phase peptide synthesis. MS and reversed-phase (RP)-HPLC were employed for sequence identification, purification, and purity analysis. The secondary structures of the peptides were investigated by circular dichroism spectroscopy. CellTiter 96^® AQueous one solution cell proliferation assay was used to evaluate the cytotoxicity of the peptides. The inhibitory activities and mechanisms of the peptides against PRRSV were studied by Western blotting, RT-qPCR, and indirect immunofluorescence assay. The MS and RP-HPLC results showed that CD and derived peptides were successfully synthesized, with the purity reaching up to 95%. Circular dichroism analysis revealed that the CD derivatives exhibited more stable and abundant α-helices in a cell membrane-mimicking environment. The MTS assay indicated that all tested peptides at 100 μg/mL had negligible cytotoxicity. The experimental results of the action phase of the peptide against PRRSV demonstrated that the derived peptides significantly enhanced antiviral activities at the viral entry stage compared with the parent peptide. This enhancement was attributed to the introduction of lysine, tryptophan, and phenylalanine, which increased the hydrophobicity and positive charge of the peptides. These findings provide a theoretical basis for the application and structural optimization of antiviral peptides and may offer a new strategy for preventing and controlling PRRSV.
Porcine respiratory and reproductive syndrome virus/physiology* ; Animals ; Swine ; Antiviral Agents/chemistry* ; Porcine Reproductive and Respiratory Syndrome/virology* ; Virus Internalization/drug effects* ; Antimicrobial Peptides/chemistry*

Tissue swelling is a common symptom in clinic. With the development of proper technology of traditional Chinese medicine, mirabilite for external application has been widely applied in clinic to relieve tissue swelling with curative effect. This paper summarized the mechanism of action of mirabilite for external application and its current situation in relieving tissue swelling. This paper also pointed out an open question based on existing studies and offered a corresponding proposal.

[Summary] The HK-2 cells with different culture media were divided into normal glucose group (NG group,5.5 mmol/L D-glucose) ; high glucose group (HG group,30 mmol/L D-glucose) ; mannitol group (MG group,5.5mmol/L D-glucose+24.5 mmol/L mannitol) ; 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] groups (V1-V3 group)which were exposed to medium containing 30 mmol/L D-glucose and different concentrations of 1,25-(OH)2D3 ;Nethyl-cysteim control group (NAC group,30 mmoL/L D-glucose + 1.0 mmol/L N-Nethyl-cysteim) ; and ethanol control group(SG group,30 mmol/L D-glucose+6.86 × 10-2 mol/L ethanol).The level of intracellular reactive oxygen species,mitochondrial membrane potential,activity of total-superoxide dismutase (T-SOD),level of malondialdehyde,expression of UCP2 mRNA and protein in HK-2 cells were detected.Compared with NG group,the mitochondrial membrane potential significantly decreased in HG group (P＜0.01),and the mitochondrial membrane potential in V group was lower than that in HG group(P＜0.01).The activity ofT-SOD in HG group was significantly lower than that in NG group(P＜0.01),while its level of malondialdehyde was significantly higher than that in NG group(P＜0.01).Compared with HG group,the activity of T-SOD in V groups was significantly increased (P＜0.05)and the level of malondialdehyde in these groups significantly decreased (P＜0.01).The mRNA expression of UCP2 in HG group was increased significantly in comparison with NG group (P ＜ 0.05) and the expression in V groups was significantly decreased in comparison with HG group (P＜0.01).The results suggest that 1,25-(OH)2D3 could reduce the mitochondrial membrane potential,the production of reactive oxygen species,and regulate the expression of UCP2 in order to suppress the oxidative stress induced by high glucose.

Objective To investigate physical activities of preschool children by gender and to explore the effects of activity type on bone indexes.Methods During 2009 and 2010,397 preschool children of 3-5 years old were randomly selected from 4 kindergartens in Chengdu Province of China.Ultrasound bone analyzer was used to assess children's bone mass.A physical activity questionnaire was completed by parents to evaluate physical activities at leisure time.Student's t test and least square regression were used for data analysis.Results Concerning activity types,boys spent more leisure time on running and Wushu than girls did (t values were 1.94 and 2.84,respectively ; both P ＜ 0.05).However,girls spent more time on dancing (0.78 h),jumping rope (0.08 h) and manual labour (0.22 h) each day (t values were-9.50,-3.43 and-1.92,respectively; all P ＜ 0.05).The weekly total exercise time and energy consumption per unit of body weight of girls vs.boys were 7.29 vs.6.51 h and 127.57 vs.113.85 kJ (t values were 2.63 and 2.04,respectively ; both P ＜ 0.05).About per day time on sleeping and per week time on watching television,there were no significant difference between boys and girls (t =0.180,0.520;P ＞0.05).But boys spent more time on electronic game and computer than girls (t =0.760,2.510;P ＜ 0.05).The normalized correlation coefficient for bone mass and moderate physical activities or jumping was 0.184 and 0.275,respectively (both P ＜ 0.05).Conclusions Our data suggest that preschool children's bone volume may be positively correlated with moderate physical activities and jumping activities.Introducing some moderate physical activities or activity appliance,toys and playing fields as well as increasing professional training might be helpful.

It is a clinical nursing management that can be adapted to chinese characteristic and the market ecnomic body.We studied 194 cases of patients nursed by 3-level nursing ward attendance using nursing procedure, and compared itwith the traditional way. Reault: The beneficial indicator of the study group was significantly higher than that of thetraditional group. 3 - level hursing ward attendance using nursing procedure is a scientific nursing management way. Itembodied the patients- centralized - nursing - management mode. The knoweldge and application of nursing managementwere also developed and increased