Non-steroidal anti-inflammatory drugs induce apoptosis in implanted hepatoma of mice

AIM: To study the mechanism of the effect of NSAIDs on apoptosis in mice hepatoma at anti-inflammatory doses. METHODS: Kunming breed mice were inoculated subcutaneously in the flank with mice hepatoma H22 cell line. The effects of ibuprofen, indomethacin, and nimesulide on apoptosis were determined by using electron microscopy, agarose gel electrophoresis, flow cytometry, and Western blot analysis of the expression of c-myc, bcl-x_L and bcl-2 proteins. RESULTS: NSAIDs induced apoptosis of mice implanted hepatoma, which includes the morphological changes such as reduction in the volume, and the nuclear chromatin condensation, as well as the "ladder pattern" revealed by agarose gel electrophoresis of DNA. The apoptotic index was increased to 15%±1.0%, 29.7%±1.5%, 46.3%±3.5% from 3.3%±0.6% by detecting Sub-G₁ peaks on flow cytometry. Western blot analysis showed that levels of bcl-2 and bcl-x_L were significantly reduced by treatment with nimesulide. Ibuprofen and indomethacin decreased bcl-2 expression but increased bcl-x_L expression. C-myc wasn't changed in these groups. CONCLUSION: These results suggest that NSAIDs induces apoptosis of mice hepatoma, which may be due to their regulation on the expressions of bcl-2 family genes.     

山羊卵巢无腔卵泡的体外发育

在三维琼脂凝胶培养体系中 ,山羊无腔卵泡的生长模式类似于体内。在一定培养时间内能善为保持其完整的立体结构和形态。原始卵泡能在体外启动 ,并得到一定程度的生长。初级卵泡能发育为次级卵泡 ,次级卵泡发育为有腔卵泡。卵泡在体外发育过程中 ,表现出了明显的优势化。本试验首次初步揭示了山羊无腔卵泡的体外发育基本过程和规律。     

Physicochemical properties of the thermal gel of water-washed meat in the presence of the more soluble fraction of porcine sarcoplasmic protein

We investigated the physicochemical properties of the thermal gel of water‐washed pork meat (WWM) in the presence of the soluble fraction of porcine sarcoplasmic protein (SP) obtained with ammonium sulfate at 75 percent saturation. Two precipitated fractions of SP were obtained at 0–50 percent and 50–75 percent saturation, named SP‐f1 and SP‐f2, respectively, and the soluble fraction obtained at 75 percent saturation, SP‐f3, was used. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis showed that SP‐f3 contained mainly glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), while SP‐f1 and SP‐f2 had other SPs such as phosphorylase b, enolase, actin and phosphoglycerate mutase. The gel strength of WWM was greater when SP‐f3 rather than one of various animal proteins such as bovine plasma (BP), egg white, or whey protein isolates (WPI), was added and SP‐f3 had a gel‐enhancing effect as good as that of polyphosphate (PP). The gel strength of WWM with added SP‐f3 increased significantly with NaCl at 0.15 mol/L or more, but not in the absence of NaCl (0 mol/L). The effect of SP‐f3 was evident at neutral pH and maximum gel strength was obtained at a pH above 6.0. Differential scanning calorimetric (DSC) analysis showed that an endothermic peak corresponding to myosin heads in WWM shifted to a lower temperature with the addition of SP‐f3, as in the case of PP, though there was no such shift in the presence of other animal proteins (BP, egg white and WPI), suggesting that SP‐f3 increases the gel strength of WWM through the dissociation of actomyosin similar to PP. Scanning electron microscopy (SEM) revealed wall‐like structures among the protein strands in the WWM gel matrix in the presence of SP‐f3. The results of DSC and SEM indicated that the formation of a gel network in meat products is reinforced with GAPDH in SP after the interaction between GAPDH and myofibrillar protein.     

7种小蠹虫酯酶同工酶的比较研究

检疫性小蠹虫的鉴定,因其虫体小,种间形态特征难以准确把握,给木材的检疫工作带来较大困难。当遇到幼虫时还需饲养为成虫再进行鉴定,增加了工作难度。应用聚丙烯酰胺凝胶电泳技术对俄罗斯进境木材7种小蠹虫幼虫、成虫的酯酶同工酶进行了比较分析。结果表明7种小蠹虫幼虫酶带数目均比成虫多,酶活性也较成虫强。幼虫和成虫之间有多条迁移率接近的酶带,酶带相似性及聚类分析均证明可以将这些酶带作为种的特征性谱带。研究表明,当形态特征作为鉴定标准较难准确掌握时,可用幼虫或成虫同工酶电泳图谱来鉴定其种类。     

香菇病毒快速检测

应用十二烷基磺酸钠聚丙烯酰胺(SDS-PAGE)凝胶电泳分析香菇菌丝蛋白质,根据能否检出22 000道尔顿的34nm香菇病毒外壳蛋白带作为菌株是否带病毒的指标。在生长不正常香菇菌株和对照的带病毒菌株中均检测出了34nm香菇病毒外壳蛋白带。这一结果表明,应用SDS聚丙烯酰胺凝胶电泳可对香菇病毒进行简单、快速的早期检测。     

用大肠杆菌K99和F41菌毛抗原检测牛血清抗体的琼脂扩散试验的研究

用含２ｍｏｌ／Ｌ尿素的磷酸盐缓冲液以热处理方法提取的Ｋ９９和Ｆ４１菌毛作为抗原,对琼脂扩散试验方法进行研究。结果表明本试验方法简便,特异性强,敏感性高,可用于血清抗体检测;所制备的抗原稳定、重复性好。     

DNA recovery from agarose gels with a simple centrifuge-driven sephadex filtration

Conventional methods of DNA recovery from agarose gel generally require expensive equipment, extended elution times, or considerable handling of the sample after elution. We developed a simple protocol for a quick and effective recovery of DNA from agarose gels with good yield and quality. Using a Sephadex resin filled spin column, DNA fragments of 500 bp to 6 kb in an agarose gel slice were easily recovered by a 2 min centrifugation. The recovery efficiencies were over 40%-50% and the eluted DNA can be used directly for downstream application, such as polymerase chain reactions (PCR) and restriction enzyme digestion. This method could also be used to recover large DNA fragment (48 kb) without degradation. The use of Sephadex helps to remove small molecular impurities from agarose and it also reduces the chance of clogging the column filter caused by direct contact with agarose.