耐碱性芽孢杆菌碱性淀粉酶的研究：Ⅱ.菌株的诱变与产酶条件

耐碱性巨大芽孢杆菌（Ｂａｃｉｌｌｕｓ ｍｅｇａｔｅｒｉｕｍ）９－Ａ２经紫外线、甲基磺酸乙酯和硫酸二乙酯等多次诱变处理,获得一株产碱性α－淀粉酶能力较高的变异株Ｌ－４９。Ｌ－４９菌株比出发株的产酶能力提高近２．５倍,当以酵母膏为氮源,可溶性淀粉为碳源,初始ｐＨ９￣１０,种龄１８ｈ,接种量５％（Ｖ／Ｖ）,３０℃培养４８ｈ,酶活力可达７３０μ／ｍｌ。     

水库对投饵网箱养鱼的负荷力

本文用１８个１４．３ｍ￣３的围隔组成的围隔群,以鲤为材料,研究了水库对投饵网箱养鱼的负荷力。实验中观测了水温、透明度、ｐＨ值、溶氧、化学耗氧量、生化需氧量与非离子氨等环境因素的变化。结束时将这些变化与我国渔业水质标准相比较,查明该负荷力约为３０００ｋｇ·ｈａ￣（－１）,建议增加２５－３５％的安全储备,以最大载鱼量１８００－２３００ｋｇ·ｈａ￣（－１）作为推荐值。     

大脑皮层信息传输和精神分裂症

本工作用脑电图为测试手段,比较了正常人与精神分裂症病人的大脑皮层的信息传输。我们发现精神分裂病人的大脑皮层信息传输有非常特殊的现象。正常人在睁眼时大脑皮层信息传输比较活跃,当闭眼时信息传输相对减少。而精神分裂症病人则恰好相反。闭眼时信息传输很活跃而睁眼对它们产生抑制,严重的情况可与正常人深度睡眠时类似。经过近三百多例的统计分析这种差别是非常显著的。我们认为这种方法可能作为诊断精神分裂症的客观指标。     

Genetic counseling of a couple presenting respectively terminal transverse defects and congenital arthrogryposis.

A 29-year-old woman consulted together with her husband for a problem of congenital joint contractures. Clinical findings in the woman were characteristic of "amyoplasia congenita". In view of the severe distal limb involvement, the possibility of a distal arthrogryposis was also considered. Unexpectedly, the husband presented terminal transverse defects, mainly of the feet, suggestive of Adams-Oliver syndrome, an autosomal dominant condition with variable expression. This discovery significantly altered the counseling given to the couple, i.e. they had to be given a high recurrence risk for congenital limb malformations in their offspring and rigorous echographic monitoring of future pregnancies was advised.     

Low-molecular-weight substrate for the lysozyme of T4 bacteriophage.

It has been shown that muropeptide CB, the chemically defined product of Escherichia coli B murein digestion by phage lambda endolysin, is the substrate for T4 lysozyme. This is the tetrasaccharide GlcNAc-MurNAc-GlcNAc-anMurNAc in which the carboxyl groups of MurNAc and anMurNAc residues are substituted by tetrapeptide LAla-DGlu-msA2pm-DAla (MurNAc = N-acetylmuramic acid, GlcNAc = N-acetyl-D-glucosamine, anMurNAc = 1,6-anhydro-N-acetylmuramic acid, LAla = L-alanine, DGlu = D-glutamic acid, msA2pm = meso-diaminopimelic acid). The substrate contains one bond hydrolysable by T4 lysozyme. The products of hydrolysis are the easily identifiable disaccharide muropeptides C6 (GlcNAc-MurNAc-LAla-DGlu-msA2pm-DAla) and CA (GlcNAc-anMurNac-LAla-DGlu-msA2pm-DAla). Thus the substrate may be used for the specific identification of murein N-acetylmuramoylhydrolases of the T4 lysozyme type, as well as for any quantitative measurement of the enzymatic reaction.     

CX3CL1 promotes tumour cell by inducing tyrosine phosphorylation of cortactin in lung cancer

It has been reported that chemokine CX₃CL1 can regulate various tumours by binding to its unique receptor CX₃CR1. However, the effect of CX₃CL1-CX₃CR1 on the lung adenocarcinoma and lung squamous cell carcinoma is still unclear. Here, we showed that CX₃CL1 can further invasion and migration of lung adenocarcinoma A549 and lung squamous cell carcinoma H520. In addition, Western blot and immunofluorescence test indicated CX₃CL1 up-regulated the phosphorylation level of cortactin, which is a marker of cell pseudopodium. Meanwhile, the phosphorylation levels of c-Src and c-Abl, which are closely related to the regulation of cortactin phosphorylation, are elevated. Nevertheless, the src/abl inhibitor bosutinib and mutations of cortactin phosphorylation site could inhibit the promotion effect of CX₃CL1 on invasion and migration of A549 and H520. Moreover, these results of MTT, Hoechst staining and Western blot suggested that CX₃CL1 had no effect on the proliferation and apoptosis of A549 and H520 in vitro. The effects of CX₃CL1 were also verified by the subcutaneous tumour formation in nude mice, which showed that it could promote proliferation and invasion of A549 in vivo. In summary, our results indicated that CX₃CL1 furthered invasion and migration in lung cancer cells partly via activating cortactin, and CX₃CL1 may be a potential molecule in regulating the migration and invasion of lung cancer.