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1.
Summary It has been demonstrated that the genetic polymorphism of human serum orosomucoid (ORM) is controlled by polymorphic ORM1 and monomorphic ORM2 loci. In this study a Japanese family was encountered in which several members had puzzling electrophoretic patterns consisting of four bands. The ORM patterns were due to the products of a duplicated ORM1 locus haplotype (ORM1 * 2·1) or the products of new variant alleles at the ORM2 locus. The ORM1 * 2·1 haplotype is very common in the Japanese population, occurring at an allele frequency of 0.16. The increased occurrence of ORM1 2-1 and the heterogeneity in band intensity among ORM1 2-1 phenotypes could be explained in terms of a duplicated gene ORM1 * 2·1. The ORM2 locus proved to be polymorphic, with six alleles in the Japanese population. Dedicated to Professor Dr. K. Nishigami on the occasion of his 60th birthday  相似文献   
2.
To study the role of leukotriene C4(LTC4) and the effect of hydrocortisone and aminophylline on plasma LTC4 levels in patients with asthmatic attacks, we measured LTC4 in plasma of 18 asthmatics during a wheezing attack and of 7 normal subjects. Blood samples were obtained before and after treatment with aminophylline and/or hydrocortisone injections. We extracted LTC4 using a Sep-Pak C18 cartridge for the measurement of LTC4 by radioimmunoassay. The plasma levels of immunoreactive LTC4 (i-LTC4) of the normal subjects were 142 +/- 25 pg/ml (n = 7), while those of nonatopic type asthmatic patients with wheezing attacks were 208 +/- 68 pg/ml (n = 15) (p less than 0.01). Before and after treatment with both hydrocortisone succinate (100 mg) and aminophylline (250 mg), 6 asthmatic patients with wheezing attacks had a mean plasma level of i-LTC4 181 +/- 24 and 132 +/- 18 pg/ml (p less than 0.01), respectively. On the other hand, the treatment with aminophylline 250 mg alone increased the i-LTC4 levels from 178 +/- 19 pg/mg to 213 +/- 16 pg/mg (n = 6)(p less than 0.05), while treatment with hydrocortisone succinate 100 mg decreased the i-LTC4 level 0.05 from 284 +/- 99 pg/ml to 249 +/- 85 pg/ml (n = 4)(p less than 0.05). In conclusion, the present study shows that the i-LTC4 level in venous blood of patients with asthmatic attacks is decreased significantly by treatment with hydrocortisone succinate.  相似文献   
3.
Summary Peripheral blood lymphocytes were cultured for 5 days with allogeneic tumor cells (allogeneic mixed lymphocyte/tumor cell culture), and subsequently cultured with recombinant interleukin-2 for 12 days. These cultured cells were found to be cytotoxic to autologous tumor cells. Results of two-color analysis using monoclonal antibodies to cell markers showed that more than 80% of their cultured cells were CD3+ cells, and CD4+ cells showed a higher distribution than CD8+ cells. However, CD8+ cells had a much higher killing activity with autologous tumor than did CD4+ cells, when estimated by an elimination study using monoclonal antibodies to T cell phenotypes and complement. The cold-target inhibition test showed that the cytotoxicity of these cells for autologous tumor cells was inhibited by unlabeled autologous tumor cells but not by unlabeled stimulator cells. Furthermore, about 40% of the cytotoxicity was suppressed by blocking of HLA class I antigen with a monoclonal antibody on autologous tumor cells. Thus, cytotoxic activity of lymphocytes to autologous tumor restricted by target cell HLA class I antigen is possibly induced by allogeneic tumor-stimulation.  相似文献   
4.
To identify the type of Verotoxins (VT) produced by Verocytotoxin-producing Escherichia coli (VTEC), a sensitive bead-enzyme-linked immunosorbent assay and polymerase chain reaction with common and specific primers to various VTs (VT1, VT2, VT2vha, VT2vhb, and VT2vp1) were developed. Together with colony hybridization tests with oligo- and polynucleotide probes, these methods were applied to VTEC isolates to type the VT produced. The toxin types of 26 of 37 strains were identified, but the reaction profiles in assays of the remaining 11 strains suggested the existence of new VT2 variants. The application of these identification procedures may be useful as a tool for clinical and epidemiological studies of VTEC infection.  相似文献   
5.
We cloned and sequenced two new Verotoxin 2 (VT2) variant genes: one from an Escherichia coli strain from a case of bovine diarrhea and the other from an E. coli strain from a patient with diarrhea. The nucleotide and amino acid sequences of these two genes were highly homologous with, but distinct from those of the VT2, VT2vha, VT2vhb, SLT-IIv (VT2vp1) and SLT-IIva (VT2vp2) genes. Their nucleotide sequences were much more closely homologous to that of VT2vh than to that of VT2vp. Search for these two new genes in other Verocytotoxin-producing E. coli strains resulted in the isolation of 2 strains carrying one of the new VT2 variant genes, one strain from Tokyo and the other from Canada.  相似文献   
6.
PI phenotyping by separator isoelectric focusing (SIEF) was performed on a total of 1000 unrelated Japanese individuals from two different areas of Western Japan. The PI M1M4 subtype was observed together with the six common PI M subtypes. PI*M4 was confirmed to be present but rare in the Japanese. Several new PI variants were identified by comparison runs of each variant with previously reported genetic variants. The significance of treatment of serum with dithiothreitol (DTT) followed by iodacetic acid (IAC) in determination of PI variants is also described.  相似文献   
7.
Plate (or slope) cultures of endomycin-producing Streptomyces endus (KCC S-0213) showed spontaneously developing pocks which increased in number during subculturing. Neither spore formation nor typical aerial hyphae formation was observed in the pocks, whereas formation of substrate hyphase was not inhibited. Almost all of the hyphae were broken or lysed in the pocks, and many phage tail tiplike particles were observed in the pocks. No self-replication activity was associated with the particles. The particles often formed a hexagonal crystal or a large crystal mass. The production of these particles did not occur in the liquid culture or in young or normal plate cultures having no pocks. These results were similar to those obtained from the plaque-making phenomenon, except for active phage production, in thiostrepton-producing Streptomyces azureus (ATCC 14921), which has been described previously.  相似文献   
8.

1. 1. The objective of this paper is to investigate the indoor environment from the viewpoint of interaction between physical environment and the human responses. The field survey has been conducted over 1 year.

2. 2. A continuous measurement has been carried out for 1 week and distribution of variables have been measured for 1 day.

3. 3. The attitude of workers was investigated by a questionnaire.

4. 4. As the result, average luminance represented more than 1000 lx in the new building, in contrast with less tha 300 lx in the existing building.

5. 5. There was a significant difference of the occupants' response to the light environment between the two buildings.

6. 6. Measured thermal conditions are on the edge of the ASHRAE comfort envelope in summer, and in the neighborhood of the lower dry limit of the envelope in spring.

7. 7. The occupants' evaluations were remarkably changed before and after the moving. The office environment is better than that of the factory.

Author Keywords: Office; post occupancy evaluation; physical environmental condition; occupants' evaluation  相似文献   

9.
10.
PrPsc, the pathogenic isoform of PrPc, can convert PrPc into PrPsc through direct interactions. PrPc oligomerization is a required processing step before PrPsc formation, and soluble oligomers appear to be the toxic species in amyloid-related disorders. In the current study, direct interactions between vitamin D2 and human recombinant PrPc (90–231) were observed by Biacore assay, and 3F4 antibody, specific for amino acid fragment 109–112 of PrPc, inhibited this interaction. An ELISA study using3F4 antibody showed that PrPc (101–130), corresponding sequence to human PrP, was affected by vitamin D2, supporting the results of Biacore studies and suggesting that the PrPc sequence around the 3F4 epitope was responsible for the interaction with vitamin D2. Furthermore, the effects of vitamin D2 on disruption of PrPc (90–231) oligomerization were elucidated by dot blot analysis and differential protease k susceptibilities. While many chemical compounds have been proposed as potential therapeutic agents for the treatment of scrapie, most of these are toxic. However, given the safety and blood brain barrier permeability of vitamin D2, we propose that vitamin D2 may be a suitable agent to target PrPc in the brain and therefore is a potential therapeutic candidate for prion disease.  相似文献   
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