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1.
S Ikei M Ogawa T Beppu C Ohara K Sakamoto H Sameshima H Arakawa Y Yamaguchi T Yamanaka S Kudo 《Cytokine》1992,4(6):581-584
In an attempt to investigate the interaction between the changes of cytokines and acute phase reactants after transcatheter arterial chemoembolization therapy (TACE), the levels of interleukin 6 (IL-6), interleukin 8 (IL-8), C-reactive protein (CRP) and pancreatic secretory trypsin inhibitor (PSTI) in the blood of patients with unresectable hepatocellular carcinoma (HCC) were measured. Before the therapy, serum IL-6 and plasma IL-8 levels were detectable in 77.8% and 28.5%, respectively, of patients with HCC. Levels of serum IL-6 and plasma IL-8 increased after TACE and reached a peak on day 3 in all patients (18/18) and in 87.5% of patients (12/14), respectively. Both blood levels of IL-6 and IL-8 reached a peak earlier than those of CRP and PSTI did after the therapy. When the maximal values of IL-6 were compared with those of CRP and PSTI, there were significant positive correlations (r = 0.63, P < 0.01 and r = 0.81, P < 0.01, respectively). Similarly, comparisons of the maximal values of IL-8 with those of CRP and PSTI gave a significant correlation (r = 0.68, P < 0.01 and r = 0.67, P < 0.05, respectively). However, no significant correlation was found between the elevation of IL-6 and IL-8. 相似文献
2.
Gelation Phenomena Induced by Alkali-alcohol Treatment of 7S and 11S Components in Soybean Globulins
Transparent gels containing about 2% protein were obtained by mixing alkaline dope solution of 7S or 11S soybean proteins with alcohol. The 7S component showed the ability to form a stronger gel than the 11S. This phenomenon depended on pH and alcohol concentration. In 66 % ethanol, the viscosity of the 7S and 11S reached maxima at pH 11.4 and 11.2, respectively. Above these pH levels where further unfolding and dissociation into subunits of the protein molecules occur, the viscosity decreased rather. The effectiveness of alcohol to increase viscosity increased in the order; n-butanol < tert-butanol < n-propanol < iso-propanol < ethanol < methanol. Alcohols having minor hydrophobicity were more effective for increasing viscosity, but ethylene glycol was ineffective. The addition of NaCl or 2-mercaptoethanol to ethanol-mixed alkaline dope solutions resulted in the remarkable increment of the viscosity, especially for the 7S. 相似文献
3.
Mikihiko Naito Ichiro Kudo Yukiko Mukai-Sato Susumu Tsushima Hiroaki Nomura Shoshichi Nojima Keizo Inoue 《Cancer immunology, immunotherapy : CII》1987,24(2):158-164
Summary Liposomes composed of chemically synthesized glyceroglycolipids, such as 1,2-dipalmityl-[-cellobiosyl-(1 3)]-glycerol (Cel-DAG), 1,2-dipalmityl-[-lactosyl-(1 3)]-glycerol, or 1,2-dipalmityl-[-maltosyl-(1 3)]-glycerol, were found to enhance protective immunity against transplantable tumor cells (sarcoma 180) in ICR mice. Peritoneal exudate cells prepared from mice treated in vivo with Cel-DAG showed cytostatic activity in vitro against the mouse leukemia cell line, EL-4. Adherent cells separated from this preparation showed similar activity. Peritoneal cells from polypeptone-injected mice acquired appreciable cytostatic activity when incubated in vitro in the presence of glyceroglycolipid liposomes. The adherent cell fraction alone showed rather weak cytostatic activity when pretreated with the glyceroglycolipids, and full activity was restored by supplementing with the nonadherent cell fraction. The ability of glycolipids to induce tumoricidal effects was affected by cholesterol content: with increasing cholesterol content, the activities decreased. Cholesterol-free glycolipid liposomes were taken more efficiently by macrophages than cholesterol-containing liposomes. Cholersterol modifies the surface property of glyceroglycolipid liposomes. Activation of macrophages is responsible for enhancement of protective immunity against tumor cells by injection of these glycolipids in vivo.This work was supported in part by Grants-in-Aid (Nos. 58010010, and 59870076) for Scientific Research from the Ministry of Education, Science and Culture of Japan 相似文献
4.
Structure and pre-B lymphocyte restricted expression of the VpreB in humans and conservation of its structure in other mammalian species. 总被引:11,自引:1,他引:10
DNA from several mammals, including humans, was found to contain one or more restriction enzyme digested DNA fragments which hybridized to the mouse VpreB gene under stringencies demonstrating at least 70% nucleotide sequence homologies, indicating that the VpreB locus may be widespread and highly conserved among mammals. A human VpreB genomic clone was isolated and sequenced. Two exons and the intervening intron are spaced almost identically as in the mouse VpreB1 gene, and show 76% sequence homology to the mouse gene. As in the mouse VpreB1 gene, the 5' end of the human VpreB gene contains characteristic features of Ig domains, while the 3' end is Ig non-related. This 3' Ig non-related structure of the VpreB gene(s) may, therefore, have existed before the speciation of humans and mice over 65 million years ago. Sequences encoding the entire putative second framework region and a stretch in the third framework region are identical in human and mouse VpreB. the human VpreB gene appears to be selectively expressed in human pre-B cell lines as an 0.85 kb poly(A)+ RNA. Its expression promises to be a useful marker for the detection of normal and malignant human pre-B lymphocytes. 相似文献
5.
6.
Molecular cloning and expression of cellulase genes of alkalophilic Bacillus sp. strain N-4 in Escherichia coli. 总被引:14,自引:8,他引:6 下载免费PDF全文
The genes for cellulases of alkalophilic Bacillus sp. strain N-4 were cloned in Escherichia coli with pBR322. Plasmids pNK1 and pNK2 were isolated from the transformants producing carboxymethyl cellulase, and the carboxymethyl cellulase genes cloned were in 2.0- and 2.8-kilobase-pair HindIII fragments, respectively. On the DNA level, the pNK1 fragment had a different restriction map from that of the pNK2 fragment, but the genomic hybridization experiments showed partial homology among these fragments. A total of 74 and 34% of the enzyme activities were observed in the periplasmic space of E. coli carrying the plasmids pNK1 and pNK2 , respectively. The carboxymethyl cellulase thus produced had broad pH activity curves (pH of 5 to 10.9) and was stable up to 75 degrees C. 相似文献
7.
8.
Iron propagation cages were settled on sand and/or rock beds in coastal areas of Hokkaido. The cage was oxidized by dissolved oxygen and the released Fe(II) diffused into the seawater around the cage. Fe(II) concentrations in the range of 10–50 nM were detected within a 20-m distance around the cage. For comparison, in the Japan Sea, the total iron concentration is less than 2 nM.Laminaria japonica was grown in an indoor semi-continuous culture system. The critical Fe level for maintaining maximum growth, and the subsistence Fe level for survival were measured. The concentrations obtained were 14–21 and 8 g Fe g–1 tissue, respectively. Iron found inL. japonica growing on rocks and/or rock beds in the Japan Sea was close to the subsistence level. However, the Fe level inL. japonica on the cage in the Japan Sea was considerably higher. The concentrations of chlorophyll-a and fucoxanthin collected from the cage were significantly higher for sporophytes, demonstrating that iron is a very important element for the growth of seaweeds. 相似文献
9.
Microtus species are very useful as experimental small animals with herbivorous characteristics. In this report, to approach establishment of the use of Japanese field voles (M. montebelli) and Hungarian voles (M. arvalis) as experimental animals, the biological characteristics, breeding methods and reproductive performance of these animal species were comparatively investigated. The number of chromosomes of M. arvalis is 12n = 46, differing from those of M. montebelli, 2n = 30. The breeding and reproduction of the Microtus species were relatively easily accomplished in the laboratory, by giving high fiber-containing rations. These animals prove to be polyestrous and showed postpartum estrous on the day of parturition. In the breeding by the continuous mating of the same pair, there was little or no delay in implantation due to lactation, especially in M. arvalis resulting in continuous birth at intervals of 20 to 21 days. On examination of vaginal smears, Japanese field voles (M. montebelli) did not show any definite pattern whereas 23 out of 30 voles from Hungary (M. arvalis) examined showed 6- to 18-day cycles. There were remarkable differences between the Japanese voles and the Hungarian voles, both biologically and reproductively. 相似文献
10.
Construction and characterization of the chimeric enzymes between the Bacillus subtilis cellulase and an alkalophilic Bacillus cellulase 总被引:1,自引:0,他引:1
A Nakamura F Fukumori S Horinouchi H Masaki T Kudo T Uozumi K Horikoshi T Beppu 《The Journal of biological chemistry》1991,266(3):1579-1583
The amino acid sequences of cellulase from Bacillus subtilis (BSC) and that from an alkalophilic Bacillus sp. N-4 (NK1) show significant homology in most parts except for the C-terminal portions. Despite the high homology, the pH activity profiles of the two enzymes are quite different; BSC has its optimum pH at 6-6.5, whereas NK1 is active over a broad pH range from 6 to 10.5. In order to identify the structural features which determine such pH activity profiles, chimeric cellulases between BSC and NK1 were constructed using four restriction sites commonly present within the homologous coding sequences, and were produced in Escherichia coli. The chimeric cellulases showed various chromatographic behaviors, reflecting the origins of their C-terminal regions. The pH activity profiles of the chimeric enzymes in the alkaline range could be classified into either the BSC or NK1 type mainly depending on the origins of the fifth C-terminal regions. In the acidic range, the profile was determined only by the origin of the fourth enzyme region from the N terminus. Comparison of the kinetic parameters between pH 5 and 6 using p-nitrophenyl cellobioside as a substrate indicated that the fourth region is responsible for the pH-dependent change of the kcat value. Only a limited number of amino acids in the fourth region may affect on deprotonation of catalytic residues of the cellulases and modulate the catalytic activity in the acidic pH values. 相似文献