Sulphamerazine toxicity in cut-throat trout broodfish Salmo clarki (Richardson)

Treatment of cut-throat trout broodfish Salmo clarki (Richardson) with Sulphamerazine at 220 mg/kg (10 g/100 1b) of fish/day for 14 days resulted in severe kidney histopathology and increased mortality among males. Experimental data presented showed that cut-throat trout broodfish were extremely sensitive to Sulphamerazine toxicity. Hydropic degeneration of renal tubule epithelium and haemorrhage into tubule lumens were observed in kidneys of both male and female trout, but was more severe in the former. Death, which occurred only in males, was correlated with spawning stress and impaired renal function.     

Thrombocyte substitution in acute leukemia. Effect of histocompatibility on the clinical efficacy

Thrombocyte substitution is an essential prerequisite for intensive cytoreductive therapy in acute leukemia. Evaluating 228 thrombocyte transfusions in 17 patients shows that the clinical effectiveness of thrombocyte concentrates can be increased by making the coordination of HLA antigens of donor and receiver as good as possible. When measured in the corrected increment (CI) 24 hours after transfusion, the effectiveness of A3/B1 match preparations (CI = 7.0 +/- 1.6) is significantly higher than that of random preparations (CI = 3.0 +/- 0.5). With the presence of HLA antibodies an effective substitution (CI24 greater than or equal to 4.5) can only be achieved by A3/B1 match thrombocytes. This can only be realized by applying the fourfold thrombapheresis of single donors.     

Tranylcypromine: stimulation of eating through alpha-adrenergic neuronal system in the paraventricular nucleus.

Injection of norepinephrine (NE) into the paraventricular nucleus of the hypothalamus has been shown to elicit eating in satiated rats. In the present study, the monoamine oxidase inhibitor tranylcypromine (TCP), which is known to release endogenous NE, was found to produce a similar effect in rats maintained and tested on a palatable milk-mash combination diet. The effect of this antidepressant drug was positively correlated in magnitude with the NE effect in the same animals. It was selectively antagonized by central injection of drugs which block α-adrenergic receptors. Local pretreatment with NE synthesis inhibitors similarly blocked the TCP eating response but had no effect on eating elicited by exogenous NE. It is suggested from these results that TCP is stimulating eating through the release of endogenous NE from adrenergic neurons innervating the region of the paraventricular nucleus.     

Recruitment of lysozyme as a major enzyme in the mouse gut: Duplication,divergence, and regulatory evolution

Summary Two major types of lysozymec (M and P) occur in the mouse genus,Mus, and have been purified from an inbred laboratory strain (C58/J) ofM. domesticus. They differ in physical, catalytic, and antigenic properties as well as by amino acid replacements at 6 of 49 positions in the amino-terminal sequence. Comparisons with four other mammalian lysozymesc of known sequence suggest that M and P are related by a gene duplication that took place before the divergence of the rat and mouse lineages. M lysozyme is present in most tissues; achieves its highest concentration in the kidney, lung, and spleen; and corresponds to the lysozyme partially sequenced before from another strain ofM. domesticus. InM. domesticus and several related species, P lysozyme was detected chiefly in the small intestine, where it is probably produced mainly by Paneth cells. A survey of M and P levels in 22 species of muroid rodents (fromMus and six other genera) of known phylogenetic relationships suggests that a mutation that derepressed the P enzyme arose about 4 million years ago in the ancestor of the housemouse group of species. Additional regulatory shifts affecting M and P levels have taken place along lineages leading to other muroid species. Our survey of 187 individuals of wild house mice and their closest allies reveals a correlation between latitude of origin and level of intestinal lysozyme.     

下丘脑外侧区注射TRH对大鼠胃酸分泌的影响

本文采用连续收集胃腔灌流法,观察下丘脑外侧区(LHA)注射促甲状腺激素释放激素(TRH)对大鼠胃酸分泌的影响,并分析TRH在LHA促进胃酸分泌的作用机制。结果表明:(1)LHA注射TRH(1μg)明显地刺激胃酸分泌;(2)预先向LHA注射酚妥拉明(10μg)、美多心安(5μg)及胃泌素抗体1μl(1:640)并不影响TRH的泌酸作用,如预先向LHA注射阿托品(5μg)则可消除TRH的泌酸效应;(3)垂体摘除及肾上腺切除均不影响TRH的泌酸作用;(4)隔下迷走神经切断后,LHA注入TRH的泌酸效应仍然出现,但持续时间显著缩短;腹腔交感神经节摘除后,TRH仍能促进胃酸分泌,但分泌量少而平稳。以上结果提示:LHA是TRH中枢泌酸效应的有关结构之一,其中枢机制是通过胆碱能M受体中介的,腹腔交感神经节和膈下迷走神经是TRH泌酸效应的传出途径。前者引起的泌酸反应出现较早且引起泌酸高峰,但持续时间短;后者则引起低平的持续分泌。     

Respiration and soluble sugar metabolism in sugar pine embryos

Embroys excised from dormant seeds of sugar pine ( Pinus lambertiana Dougl.) incubated at 25°C (non-dormancy-breaking) or stratified at 5°C (dormancy-breaking) were analyzed to determine temperature effects on the relative activities of respiration and fermentative metabolism, the levels of soluble sugers and the activities of the hydrolytic enzymes, invertase and sucrose synthase, as related to the release of dormancy and germinatio. At 25°C, despite a sharp drop in embryo oxygen uptake after 48 h, a simultaneous decline in acetaldehyde and ethanol concentrations indicated that there was not a shift to fermentative metabolism. The concentrations of soluble sugars showed no treatment effects. Embryo invertase (EC 3.2.1.26) activity changed only slightly at either temperature, while stratification was accompanied by a 4-fold increase in sucrose synthase (EC 2.4.1.13) activity (cleavage direction). Upon transfer of stratified seeds to 25°C, embryo sucrose synthase activity rapidly increased almost 10-fold, with the increase beginning prior to germination, while mvertase activity increased 20-fold, concomitant with germination.     

立枯丝核菌蛋白质电泳图谱研究 Ⅰ.融合群与图谱的相关性

用来自日本和美国的立枯丝核菌8个融合群11个类群代表菌株进行可溶性蛋白质电泳,其结果表明,各融合群及亚群之间电泳图谱有显著差异,而同一类群菌株的电泳图谱则相似。分析来源于华东等地已鉴定的融合类群117个菌株的电泳图谱显示,同一融合群内菌株,虽然采集地区、寄主植物或致病力不同,其蛋白质图谱仍十分相似;而不同融合类群的菌株,即使在同一田块中同一种寄主植物上引起相似病害,其图谱也显示出明显差异。本文就上述可溶性蛋白质图谱显示的结果与其它研究者在血清学、DNA同源性.酯酶等生化水平上对融合群的研究结果进行了比较和探讨。