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51.
The purpose of this study was to develop an effective potential wound dressing material based on a polyvinyl alcohol (PVA) and tannic acid (TA) composite film. To prepare the PVA/TA films, PVA and TA blended aqueous solutions were cast into film form by spreading the solutions and drying them. Then the films were heat treated at 155 oC for 3 min to promote esterification between the PVA and TA. After removing un-crosslinked moieties from the films by rinsing and drying, the films were investigated by swelling behavior, FTIR spectroscopy, XRD and TGA. And, the antibacterial and antioxidant abilities of the films were also examined in this study. Through this investigation it was discovered that TA effectively acts as a functional antibacterial and antioxidant agent as well as crosslinker in the PVA/TA system. Thus, the PVA/TA composite films prepared by the casting and heat treatment method proposed in this study are expected to be used for topical medication, such as wound dressing material.  相似文献   
52.
53.
The white-backed planthopper, Sogatella furcifera (Horváth) (Hemiptera: Delphacidae), is a major pest of rice and has long-range migratory behavior in Asia. Microsatellite markers (simple sequence repeats) have been widely used to determine the origins and genetic diversity of insect pests. We identified novel microsatellite loci for S. furcifera samples collected from Laos, Vietnam, and three localities in Bangladesh from next-generation Roche 454 pyrosequencing data. Size polymorphism at 12 microsatellite loci was verified for 40 adult individuals collected from Shinan, South Korea. The average number of alleles per locus was 7.92. The mean values of observed (Ho) and expected heterozygosities (HE) were 0.615 and 0.757, respectively. These new microsatellite markers will be a resource for future ecological genetic studies of S. furcifera samples across more broad geographic regions in Asia and may assist in estimations of genetic differentiation and gene flow among populations for implementation of more effective management strategies to control this serious rice pest.  相似文献   
54.
The epithelial–mesenchymal transition (EMT) of cancer cells is a crucial process in cancer cell metastasis. An Aquimarina sp. MC085 extract was found to inhibit A549 human lung cancer cell invasion, and caprolactin C (1), a new natural product, α-amino-ε-caprolactam linked to 3-methyl butanoic acid, was purified through bioactivity-guided isolation of the extract. Furthermore, its enantiomeric compound, ent-caprolactin C (2), was synthesized. Both 1 and 2 inhibited the invasion and γ-irradiation-induced migration of A549 cells. In transforming growth factor-β (TGF-β)-treated A549 cells, 2 inhibited the phosphorylation of Smad2/3 and suppressed the EMT cell marker proteins (N-cadherin, β-catenin, and vimentin), as well as the related messenger ribonucleic acid expression (N-cadherin, matrix metalloproteinase-9, Snail, and vimentin), while compound 1 did not suppress Smad2/3 phosphorylation and the expression of EMT cell markers. Therefore, compound 2 could be a potential candidate for antimetastatic agent development, because it suppresses TGF-β-induced EMT.  相似文献   
55.
Objective  Although variations exist between species with respect to outcomes after cryopreservation, little is known about the differences in the susceptibility of the corneal stroma to cryoinjury. We performed this study to investigate freeze–thaw-induced damage in keratocytes and collagen in rabbit, pig, and human corneas.
Animals studied  Rabbit, pig, and human.
Procedures  We prepared 250-μm-thick anterior stroma from rabbit, pig, and human corneas after scraping off the epithelium and endothelium. Each 250-μm-thick corneal stroma without epithelium was placed in a 50-mL tube, frozen with liquid N2 for 15 min and taken out to thaw rapidly at 37 °C. This procedure of rapid freezing and thawing was repeated three times. Differences between the species with respect to cells and collagen structures were examined using hematoxylin–eosin (H&E) staining, terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) assay, and transmission electron microscopy (TEM). We orthotopically transplanted the pig and rabbit corneal transplants after the triple freeze–thaw cycle into rabbit eyes and evaluated graft survival.
Results  On gross examination, rabbit corneas became opaque after the triple freeze–thaw procedure, while pig and human corneas remained transparent. Histologically, keratocytes were apoptotic on TUNEL assay and TEM in rabbit, pig, and human corneas. Collagen fibrils were fragmented and the arrangement of collagen fibrils was severely disturbed in rabbit corneas on H&E staining and TEM; collagen was well preserved in pig and human corneas. Rabbit corneal stroma underwent autolysis after transplantation, whereas the pig corneal stroma remained clear for 1 month.
Conclusions  Our study showed that rabbit corneal stroma was more susceptible to freeze–thaw injury than pig and human corneas.  相似文献   
56.
This study compared the performance of female Holstein calves fed either whole milk (WM) or milk replacer (MR) having similar gross composition to WM. Calves (n = 20) were separated from their mothers within 2 h of birth, weighed, moved into individual pens, and fed colostrum (10% of their BW over 2 feedings daily) for the first 3 d. Calves were alternately assigned to either WM (n = 10) or MR (n = 10) and were fed using mobile plastic bottles. At each feeding, diluted MR was prepared in buckets by mixing 0.143 kg of MR powder (as-is basis) in 1 L of lukewarm water. Calves on both treatments were fed (1.8 L/feeding) for 4 times daily for the first 25 d of age. Feeding frequency was reduced to 3 times daily for next 5 d, then to 2 times daily for next 14 d, and then to once daily during the last 5 d of the preweaning period. Feed intake, growth, and health variables were monitored until calves were 70 d of age. Mean daily consumption of WM and MR was similar in both treatment groups (P = 0.74). Initial BW of calves fed either WM or MR was similar (42.1 +/- 3.3 vs. 41.9 +/- 2.9 kg, respectively; P = 0.83). Calves fed WM or MR daily consumed similar amounts of calf starter (1,019 vs. 1,056 g, respectively; P = 0.32), hay (121.5 vs. 126.3 g, respectively; P = 0.30), and water (5.2 vs. 5.0 kg, respectively; P = 0.54). At weaning (d 49) and postweaning (d 70), BW was greater (P = 0.03 and P = 0.02, respectively) in calves fed WM than in those fed MR. Mean DMI from both solid and liquid feeds was not affected by the treatments during the preweaning (P = 0.21) and postweaning (P = 0.16) periods. Body weight gain efficiency during preweaning and overall was improved (P = 0.001 and P = 0.002, respectively) in calves fed WM than in those fed MR. Health (days scoured, rectal temperature, respiratory score, and general appearance score) and serum chemistry variables (glucose, total protein, urea N, nonesterified fatty acids, and creatinine) in calves were not affected (P >or= 0.12 and P >or= 0.12, respectively) by the treatments. Even though gross composition of the MR and WM was similar, growth was greater in calves fed WM. Calves fed WM consumed similar amounts of DM and were heavier than those fed MR, probably because of better bioavailability (digestion and assimilation) of nutrients and availability of some unknown growth factors from WM.  相似文献   
57.
Lee JH 《Veterinary microbiology》2009,135(3-4):401-405
The present study was to investigate antimicrobial resistance profiles of Escherichia coli O26 and O111 from cattle and to characterize the virulence genes of the resistant isolates. This paper reports the high prevalence of antimicrobial resistant E. coli O26 and O111 from cattle. Among 37 E. coli O26 and 25 E. coli O111 isolates from the fecal specimens obtained from cattle, 26 (70%) and 15 (60%) were resistant to at least one antibiotic, respectively. Forty (98%) of the 41 resistant isolates were resistant to two or more antibiotics. Among the 22 antibiotics tested in this study, ampicillin was the most common antibiotic that the isolates were resistant to, followed by tetracycline and streptomycin. None of the isolates were resistant to fluoroquinolones, such as ciprofloxacin, ofloxacin and norfloxacin, and to ceftriaxone, amikacin and imipenem. Eighteen different resistant types among the 41 isolates were observed by the cluster analysis. The most frequent antibiotic-resistance type was ampicillin-tetracycline-streptomycin-cephalothin-sulfisoxazole-ticarcillin-kanamycin-minocycline-piperacillin-chloramphenicol, which accounted for 9 (22%) of the resistant isolates. The observation of frequent and multiple resistances to antibiotics highlights the need for their careful use if their benefits are to be preserved. PCR analysis of the EHEC virulence markers showed that 25 of the resistant E. coli O26 and O111 isolates tested positive for stx2 or both stx1 and stx2. This suggests that the majority of these isolates can cause serious diseases in humans and may complicate the future therapeutic options under development.  相似文献   
58.
This study was to investigate the anti-obesity effects of diglyceride (DG)-conjugated linoleic acid (CLA) containing 22% CLA as fatty acids in C57BL/6J ob/ob male mice. There were four experimental groups including vehicle control, DG, CLA, and DG-CLA. The test solutions of 750 mg/kg dose were orally administered to the mice everyday for 5 weeks. CLA treatments significantly decreased mean body weight in the obese mice throughout the experimental period compared to the control (p < 0.01). All test solutions significantly decreased the levels of triglyceride, glucose and free fatty acids in the serum compared with control (p < 0.05). The levels of total cholesterol were also significantly reduced in DG and DG-CLA groups compared with the control group (p < 0.05). CLA significantly decreased weights of renal and epididymal fats compared with the control (p < 0.05). DG and DG-CLA also significantly decreased the epididymal fat weights compared with the control (p < 0.05). A remarkable decrease in the number of lipid droplets and fat globules was observed in the livers of mice treated with DG, CLA, and DG-CLA compared to control. Treatments of DG and CLA actually increased the expression of peroxisome proliferator-activated receptor gamma. These results suggest that DG-CLA containing 22% CLA have a respectable anti-obesity effect by controlling serum lipids and fat metabolism.  相似文献   
59.
60.
Carbon nanotube (CNT)/magnetite (Fe3O4) nanocomposites were successfully fabricated by nanocoating. When the CNT/Fe3O4 nanocomposites were added to a carbonyl (CI) based magnetorheological fluid (MRF), the magnetic rheological properties of the MRF were enhanced. Such enhancement in magnetic rheological properties of the CI-CNT/Fe3O4 MRF is considered to be attributable to both the superparamagnetic property of the magnetic layer covering the CNT surface and the high length to diameter ratio of the CNT/Fe3O4 nanocomposite. Impact properties for CI-CNT/Fe3O4 MRF treated Kevlar fabrics were also tested, and improved impact properties were observed with external magnetic fields compared to CI-MRF treated Kevlar fabrics.  相似文献   
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