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21.
With the rapid rise in the emergence of bacterial strains resistant to multiple classes of antimicrobial agents, there is an urgent need to develop novel antimicrobial therapies to combat these pathogens. Cationic host defence peptides (HDPs) and synthetic derivatives termed innate defence regulators (IDRs) represent a promising alternative approach in the treatment of microbial-related diseases. Cationic HDPs (also termed antimicrobial peptides) have emerged from their origins as nature’s antibiotics and are widely distributed in organisms from insects to plants to mammals and non-mammalian vertebrates. Although their original and primary function was proposed to be direct antimicrobial activity against bacteria, fungi, parasites and/or viruses, cationic HDPs are becoming increasingly recognized as multifunctional mediators, with both antimicrobial activity and diverse immunomodulatory properties. Here we provide an overview of the antimicrobial and immunomodulatory activities of cationic HDPs, and discuss their potential application as beneficial therapeutics in overcoming infectious diseases.  相似文献   
22.
This paper describes an investigation in the fabric longi-tudinal compressibility of thirty-one suiting and trouse-ring materials using a newly developed device attached to the advanced Instron extensometer Model4466.The at-tachment was designed mainly to ensure a correct align-meat of fabric plane at the start of compression.Usingthe newly developed testing method,fabric longitudinalcompression curve was obtained and the results of longi-tudinal compressibility measured by two different com-pression load ranges(from 0 to 0.5 N/m width and 0 to1 N/m width)were examined.In addition,their rela-tionships with the fabric low-stress mechanical proper-ties measured by the KES-F system were investigatedusing statistical analysis.The results clearly indicatedthat significant differences existed when substituting fab-ric longitudinal compressibility with fabric extensibilitymeasured using the KES-F system under a low-load.Significant infiuence of yarn rotational movement in fab-ric on the longitudinal compressibi  相似文献   
23.
The ubiquitous occurrence of perfluorinated compounds (PFCs) in environmental samples has drawn much attention. Recent human exposure studies found relatively high perfluorooctane sulfonate (PFOS) concentrations in blood samples from several cities in China when compared with other countries. The objectives of the present study were: (1) to measure PFC concentrations and compositions in chicken egg samples from local markets in China; and (2) to conduct a preliminary human health risk assessment of egg consumption. Eight pooled egg samples from eight locations were analyzed for 11 PFCs. The results showed that close to 100% of the PFOS in the egg was distributed in egg yolk and PFOS was not detected in egg white (〈0.08 ng/g wet weight, w/w). Of the perfluoroalkylsulfonates, only PFOS was detected in all egg samples, while of the perfluoroalkylcarboxylates, perfluoroundecanoic acid (PFUnDA) was detected in all samples, followed by perfluorooctanoate (PFOA) (75% occurrence) and perfluorodecanoic acid (PFDA) (50% occurrence). PFOS concentrations in egg ranged from 45.0 to 86.9 ng/g w/w. The results suggested that current concentrations of PFOS in domestic chicken eggs are unlikely to cause immediate harm to Chinese populations.  相似文献   
24.
In this paper, we describe the fabrication of a new biodegradable porous scaffold composed of polycaprolactone(PCL) and magnesium(Mg)micro-particles. The compressive modulus of PCL porous scaffold was increased to at least 150% by incorporating 29% Mg particles with the porosity of 74% using Micro-CT analysis. Surprisingly, the compressive modulus of this scaffold was further increased to at least 236% when the silane-coupled Mg particles were added. In terms of cell viability, the scaffold modified with Mg particles significantly convinced the attachment and growth of osteoblasts as compared with the pure PCL scaffold. In addition, the hybrid scaffold was able to attract the formation of apatite layer over its surface after 7 days of immersion in normal culture medium, whereas it was not observed on the pure PCL scaffold. This in vitro result indicated the enhanced bioactivity of the modified scaffold. Moreover, enhanced bone forming ability was also observed in the rat model after 3 months of implantation. Though bony in-growth was found in all the implanted scaffolds. High volume of new bone formation could be found in the Mg/PCL hybrid scaffolds when compared to the pure PCL scaffold. Both pure PCL and Mg/PCL hybrid scaffolds were degraded after 3 months. However, no tissue inflammation was observed. In conclusion, these promising results suggested that the incorporation of Mg micro-particles into PCL porous scaffold could significantly enhance its mechanical and biological properties. This modified porous bio-scaffold may potentially apply in the surgical management of large bone defect fixation.  相似文献   
25.
Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.  相似文献   
26.
The rotor spun yarn(OE yarn),twist of which is calledlayering twist,was added a few involving twist,and itsstructure and properties were measured.The experimen-tal results have shown that the morphological structure ofthe rotor spun yarn with modified twist was changed andits tensile properties and abrasion resistance were im-proved.  相似文献   
27.
Antimicrobial peptides are host defence molecules that play a potential role in preventing infection at the epithelial surfaces. Ribonuclease (RNase)-7 has been shown to possess a broad spectrum of microbicidal activity against various pathogens. Here, we demonstrate that RNase-7 protein is localised to the superficial layers of ocular surface cells and increased in response to interleukin (IL)-1β, suggesting an active role during inflammation related to ocular surface infection. Signal transduction pathways involved in RNase-7 expression are unknown. Involvement of transforming growth factor β-activated kinase-1 (TAK-1) activated nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathway molecules [c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38] were studied because of their importance in infection and inflammation. Blocking the MAPKs resulted in inhibition of RNase-7 expression in response to IL-1β. However, RNase-7 induction by IL-1β was not affected by inhibiting the NF-κB signalling pathway. In conclusion, our results indicate that RNase-7 expression is specifically mediated via MAPKs but not NF-κB signalling pathways.  相似文献   
28.
Thyrotoxic periodic paralysis (TPP) is a potentially life-threatening complication of thyrotoxicosis. We conducted a genome-wide association study (GWAS) and a replication study with a total of 123 southern Chinese with TPP (cases) and 1,170 healthy controls and identified a susceptibility locus on chromosome 17q24.3 near KCNJ2 (rs312691: odds ratio (OR) = 3.3; P(meta-analysis) = 1.8 × 10(-14)). All subjects with TPP also had Graves' disease, and subsequent TPP versus Graves' disease comparison confirmed that the association at 17q24.3 was specific to TPP. The area under the curve (AUC) of rs312691 genotype for risk prediction of TPP in subjects with Graves' disease was 0.73. Expression quantitative trait locus (eQTL) analysis identified SNPs in the region flanking rs312691 (±10 kb) that could potentially affect KCNJ2 expression (P = 0.0001). Our study has identified a susceptibility locus associated with TPP and provides insight into the causes of TPP.  相似文献   
29.
The central composition experimental design of multiva-riate Response Surface Method was used to formulate mathematical models aiming to predict (1) the optimum dyeing conditions of simulated waste Tikuanyin tea for wool fabric and (2) the optimum extraction conditions of a natural mordant originated from common waste eggshell. The pre - mordanting eggshell was applied to wool fabric before dyeing with simulated waste Tikuanyin tea under the optimum dyeing conditions. After mordanting the wool fabric with extracted natural eggshell solution, the prominent effect of increment in dye uptake and improvement of the properties of light fastness, washing fastness and rubbing fastness were evaluated.  相似文献   
30.
Kawasaki disease is a systemic vasculitis of unknown etiology, with clinical observations suggesting a substantial genetic contribution to disease susceptibility. We conducted a genome-wide association study and replication analysis in 2,173 individuals with Kawasaki disease and 9,383 controls from five independent sample collections. Two loci exceeded the formal threshold for genome-wide significance. The first locus is a functional polymorphism in the IgG receptor gene FCGR2A (encoding an H131R substitution) (rs1801274; P = 7.35 × 10(-11), odds ratio (OR) = 1.32), with the A allele (coding for histadine) conferring elevated disease risk. The second locus is at 19q13, (P = 2.51 × 10(-9), OR = 1.42 for the rs2233152 SNP near MIA and RAB4B; P = 1.68 × 10(-12), OR = 1.52 for rs28493229 in ITPKC), which confirms previous findings(1). The involvement of the FCGR2A locus may have implications for understanding immune activation in Kawasaki disease pathogenesis and the mechanism of response to intravenous immunoglobulin, the only proven therapy for this disease.  相似文献   
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