Conversion of 15-hydroxyeicosatetraenoic acid to 11-hydroxyhexadecatrienoic acid by endothelial cells

Cultured endothelial cells take up 15-hydroxyeicosatetraenoic acid (15-HETE), a lipoxygenase product formed from arachidonic acid, and incorporate it into cellular phospholipids and glycerides. Uptake can occur from either the apical or basolateral surface. A substantial amount of the 15-HETE incorporated into phospholipids is present in the inositol phosphoglycerides. 15-HETE is converted into several metabolic products that accumulate in teh extracellular fluid; this conversion does not require stimulation by agonists. The main product has been identified as 11-hydroxyhexadecatrienoic acid [16:3(11-OH)], a metabolite of 15-HETE that has not been described previously. Formation of 16:3(11-OH) decreases when 4-pentenoic acid is present, suggesting that it is produced by beta-oxidation. The endothelial cells can take up 16:3(11-OH) only 25% as effectively as 15-HETE, and 16:3(11-OH) is almost entirely excluded from the inositol phosphoglycerides. These results suggest that the endothelial cells can incorporate 15-HETE when it is released into their environment. Through partial oxidation, the endothelium can process 15-HETE to a novel metabolite that is less effectively taken up and, in particular, is excluded from the inositol phosphoglycerides.     

Treatment of leachate from a solid waste landfill site using a two-stage anaerobic filter

Raw leachate was treated using a two-stage upflow anaerobic filter process. Leachate from a solid waste landfill site, which received both municipal and industrial wastes, contained high organic matter (17-21 g/L COD, 13-14 g/L BOD, and 3.5-4.6 g/L volatile acids), and low metal (Zn and Fe) concentrations. Depending on sampling time, leachate composition and characteristics varied considerably. At an organic loading up to 4 g COD/day(2) media area, the BOD and COD removal percentages were 98 and 91%, respectively. The biofilters were also effective for metal removal. However, the filter effluent contained a high concentration of ammonia. System overloading was characterized by the accumulation of large quantities of volatile acids and by a now ratio of alkalinity/volatile acids, resulting in low COD removal and reduced gas production. Once the first filter was upset, the second stage could only partially respond to the volatile acids accumulated in the effluent of first filter.     

To early distinguish neonatal transient leukemoid proliferation from congenital leukemia by in vitro cell growth

To differentiate neonatal transient leukemoid proliferation from congenital leukemia at an early stage is often difficult. Bone marrow culture is found to be helpful in this aspect. A normal in vitro growth pattern suggests transient leukemoid proliferation, while an abnormal growth pattern indicates congenital leukemia. A neonate who manifested with pictures mimicking acute myeloblastic leukemia (M1), had a karyotype of 46, XY/46, XY, i(21 q). However, the in vitro growth pattern was normal and so only supportive treatment was given. All the leukemoid manifestations disappeared several months later and he is now a healthy 2 year old boy remaining in complete remission. A second neonate who also displayed features of acute myeloblastic leukemia (M2), had a karyotype of 46, XY/47, XY, + 21 and abnormal in vitro growth pattern. This neonate died at 18 days of age.     

豚鼠冰水游泳应激后血浆、肾上腺髓质和脑内组织的亮—脑啡肽含量变化

豚鼠冰水游泳应激3min后,用放射免疫法测定血浆、肾上腺髓质和脑内三个脑区组织的亮—脑啡肽(Leu-enkephalin,LEK,)含量和血浆的血管紧张肽Ⅱ(Angiotensin Ⅱ,ATⅡ)浓度变化。结果表明:在冰水中游泳应激组豚鼠的血浆、肾上腺髓质、下丘脑和纹状体组织的LEK含量和血浆的ATⅡ浓度,均较对照组豚鼠明显升高(P值均<0.01)。提示:豚鼠在冰水中紧张、剧烈游泳后,可能激活了中枢神经和周围组织内的脑啡肽能神经元和血管紧张肽原酶—血管紧张肽Ⅱ系统,从而促进LEK和ATⅡ的释放增加。     

伸展素在黄瓜胞壁中的转化及其与羟脯氨酸和异联酪氨酸的关系

用~(14)C-Pro和~3H_2-Tyr离体暗培养黄瓜子叶,发现细胞质、SECW和RCW中的Hyp/Pro和Idt/Tyr都随时间呈线性增加。这两种比值后两者高于前者,而两种比值增加速度之比在胞质部分最大、RCW中最小。表明在胞质和胞壁中都有Pro羟化和Tyr异联化过程,但羟化作用主要发生在胞质中,异联化主要在RCW中。 理化处理(高渗溶液和CHM)和放射性示踪证明胞质中存在HRGP库;它被分泌到胞壁后,先以离子键与壁结合,后转变为共价键与壁结合的伸展素。     

Gene structure and nucleotide sequence for rat cytochrome P-450c

Two clones from rat genomic libraries that contain the entire gene for rat cytochrome P-450c have been isolated. lambda MC4, the first clone isolated from an EcoR1 library, contained a 14-kb insert. A single 5.5-kb EcoR1 fragment from lambda MC4, the EcoR1 A fragment, hybridized to a partial cDNA clone for the 3' end of the cytochrome P-450c mRNA. This fragment was sequenced using the dideoxynucleotide chain termination methodology with recombinant M13 bacteriophage templates. Comparison of this sequence with the complete cDNA sequence of cytochrome P-450MC [Yabusaki et al. (1984) Nucleic. Acids Res. 12, 2929-2938] revealed that the EcoR1 A fragment contained the entire cytochrome P-450c gene with the exception of a 90-bp leader sequence. The gene sequence is in perfect agreement with the cDNA sequence except for two bases in exon 2. A second genomic clone, lambda MC10, which was isolated from a HaeIII library, contains the missing leading sequence as well as 5' regulatory sequences. The entire gene is about 6.1 kb in length with seven exons separated by six introns, all of the intron/exon junctions being defined by GT/AG. Amino- and carboxy-terminal information are contained in exons 2 and 7, respectively. These exons contain the highly conserved DNA sequences that have been observed in other cytochrome P-450 species. Potential regulatory sequences have been located both 5' to the gene as well as within intron I. A comparison of the coding information for cytochrome P-450c with the sequence of murine cytochrome P3-450 and rat cytochrome P-450d revealed a 70% homology in both the DNA and amino acid sequence, suggesting a common ancestral gene. Genomic blot analyses of rat DNA indicated that the 3-methylcholanthrene-inducible family of cytochrome P-450 isozymes is more limited in number compared to the phenobarbital-inducible isozymes. Cross-hybridization studies with human DNA suggest a high degree of conservation between rat cytochrome P-450c and its human homolog although gross structural differences do exist between the two genes.     

关于猫颌下腺神经支及其节前神经元的观察

用逆行溃变（Kohnstamm,1902;Yagita,et al.,1909;Torvik,1957）局部电刺激中枢（Chatfield,1942;Magoun et al.,1942;Wang,1943）等方法进行唾液中枢的定位,所得到结果很不一致。近年Satomi（1979）等用辣根过氧化酶（HRP）浸泡猫中间一面神经或鼓索神经,观察了脑干中逆行标记细胞的分布。但用HRP直接浸泡支配猫颌下腺的神经分支尚未见报道。此外,只见到关于鼓索神经纤维类别和数量的分析的光学显微镜研究（Foley,1945）,用光镜和电镜相结合分析颌下腺神经支中的纤