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We have established 950 and 430 oligoclonal B-lymphoblastoid cell lines (LCL) from two normal persons and eight autoimmune disease patients, respectively by using Epstein-Barr virus (EBV)-induced transformation. To re-evaluate the EBV technique for production of human monoclonal antibodies (mAb) related to infectious disease, we screened these oligoclonal LCLs for antibodies against 31 bacterial strains systematically. A total of 74 cultures out of 1380 were reactive to a total of 18 strains out of 31. Among these, eight cultures showed 10-3 antibody (Ab) titers to Pseudomonas aeruginosa serotypes C, E, F and I, Staphylococcus aureus, Serratia marcescens and Bacillus cereus. Ten cultures showed 10-2 Ab titers to Ps. aeruginosa serotypes D, E, F and I, Ps. maltophilia, Staph, epidermidis, Klebsiella ozaenae, Ser. marcescens and B. subtilis. The results reveal the further possibilities for the EBV technique to produce various infectious disease-related human mAbs.  相似文献   
63.
In a culture system in which single cells isolated from the mesophyll of Zinnia elegans L. differentiate to tracheary elements (TEs), two inhibitors of phenylalanine ammonia-lyase (EC 4.3.1.5), L-α-aminooxy-β-phenylpropionic acid (AOPP) at 10 μM inhibited lignification without reducing the number of TEs formed. These inhibitors caused intracellular changes in peroxidase (EC 1.11.1.7) activities. The inhibitors increased the activity of peroxidases bound to the cell walls and especially the activity of peroxidase bound ionically to the cell walls. In contrast, the activity of extracellular peroxidase decreased. There were five isoenzymes, P1-P5, in the ionically bound peroxidase of cultured Zinnia cells. Among the isoenzymes, P4 and P5 appeared to be specific for TE differentation. Treatment with AOPP and AIP resulted in increases in the activities of P2, P4 and P5 isoenzymes, with the most prominent increase in P5 activity. The addition of lignin precursors, including coniferyl alcohol, to the AOPP-treated cells restored lignification, and suppressed the alteration of peroxidase isoenzyme patterns caused by AOPP. The relationship between the wall-bound peroxidases and lignification during TE differentiation is discussed in the light of these results.  相似文献   
64.
Nanko  S.  Sasaki  T.  Fukuda  R.  Hattori  M.  Dai  X. Y.  Kazamatsuri  H.  Kuwata  S.  Juji  T.  Gill  M. 《Human genetics》1993,92(4):336-338
A study of the genetic association between schizophrenia and aBalI polymorphism in exon 1 of the dopamine D3 (DRD3) gene, a candidate gene for schizophrenia, was conducted. The polymorphism was examined in 91 patients whose symptoms satisfied DSM-III-R for schizophrenia and 90 controls. There were no significant differences between the groups in allele frequencies or genotype counts. Contrary to a previous report, the patients were no more likely to be homozygous than controls. Moreover, no association with the presence of illness could be demonstrated when the patients were grouped according to sex, age of onset, history of admission to psychiatric institutions or positive family history.  相似文献   
65.
A protein with relatively high homology in its N-terminal aminoacid sequence to animal parvalbumin and oncomodulin has beenidentified in leaves of rice (Oryza sativa L.). The PV-likeprotein has a relative molecular mass of 27,000 and an isoelectricpoint of 5.0. This protein was partially purified by ion-exchangechromatography, and the purified protein was found to have Ca2+-bindingactivity in a microscale Ca2+-binding assay. Furthermore, anantiserum raised against a synthetic oligopeptide based on theN-terminal amino acid sequence of this protein cross-reactedwith protein not only from rice but also from other monocotyledonousplants. (Received October 17, 1990; Accepted October 17, 1991)  相似文献   
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Grandry corpuscles in the oral mucosa of the upper bill of the duck were immunohistochemically studied using antisera against calcitonin gene-related peptide (CGRP), galanin, methionine-enkephalin, neuropeptide Y (NPY), somatostatin, substance P (SP) and vasoactive intestinal peptide (VIP). Grandry corpuscles in the lamina propria selectively showed only SP-like immunoreactivity. Herbst corpuscles distributed near Grandry corpuscles were negative to all antisera applied. Although immunoreactive products in the Grandry corpuscles were found as granules in the peripheral cytoplasm of the Grandry cell, the axon terminals and satellite cells exhibited no reactivity. In pre-embedding electron-microscopic sections, SP-like immunoreactive products visualized with 3,3-diaminobezidine were localized in the granules of Grandry cells, but no labeling was observed in the cytoplasmic matrix or cell organelles. Electron-immunocytochemical labeling with colloidal gold by the post-embedding method clearly demonstrated that the SP antigen was localized only in the granules. It is presumed that Grandry cells have a secretory function. However, the function and the method of release of the SP contained in the observed granules remains obscure. Some CGRP-, NPY-, SP- and VIP-like-immunoreactive nerve fibers with varicosities associated with blood vessels and nerve fiber bundles of various sizes were observed in the lamina propria, but no such fibers penetrated into the intraepitherial layer. Nerve fibers positive for SP and VIP were also found in the interlobular connective tissue of the palatine glands. Some SP-positive neurons were detected in the vicinity of the palatine glands.  相似文献   
69.
Ninety-six alleles (36 alleles of Japanese and 60 of Caucasian origin) from forty-eight patients with mucopolysaccharidosis IVA were investigated for structural gene alterations using Southern blot analysis. All patients had a previously demonstrated deficiency of N-acetylgalactosamine-6-sulfate-sulfatase and exhibited a wide spectrum of clinical severity. Initially, using the fulllength cDNA as a probe, five of 36 chromosomes from the Japanese patients revealed similar rearrangements with respect to DNA digested with BamHI, SacI, and XhoI. Subsequent analysis using seven genomic fragments, covering the entire gene, enhanced the detection of aberrant fragments produced by the above restriction enzymes. Conversely, the 60 chromosomes of Caucasian origin revealed no evidence of large structural rearrangements when analyzed by these methods. There was a statistically significant difference between the two populations (P < 0.01). A severely affected Japanese patient showed structural rearrangements on both chromosomes by means of BamHI blots. An 8.0-kb fragment and a highly polymorphic 7.0-kb to 11.0-kb fragment present in normal individuals disappeared and two aberrant fragments of 11.5 kb and 12.0 kb were observed. Three other Japanese patients also showed these two aberrant fragments, in addition to the normal fragment pattern, and were thus heterozygous for this rearrangement. Interpretation of Southern blots was difficult because of the complexity of polymorphic bands resulting from variable number of tandem repeat elements. However, by utilizing these aberrant fragments or polymorphic bands, carrier detection was effective, even in families with poorly characterized mutations. Hybridization with probe MG-A (5end genomic probe in intron 1) showed a 8.4-kb fragment in BamHI blots of one Japanese and one Caucasian patient; XhoI, SacI, and EcoRI blots were normal. Since this BamHI alteration was also observed in one normal control, it appears to be a rare nonpathological polymorphism.  相似文献   
70.
Seven different restriction fragment length polymorphisms (RFLPs) at the N-acetylgalactosamine-6-sulfate sulfatase (GALNS) locus were analyzed using Southern blotting and polymerase chain reaction based techniques to search for the frequency of each RFLP produced by StyI, SphI, HaeIII, StuI, HapII, XhoI, and BamHI restriction endonucleases, respectively, in 36 mutant alleles, including two sibling cases and 100 normal alleles. Calculation of heterozygosity indexes showed that these RFLPs were polymorphic, ranging from 0.31 to 0.69 in mucopolysaccharidosis IVA (MPS IVA) patients compared with 0.21 to 0.65 in normal individuals. There was some significant difference in several RFLPs and in the combination with four kinds of RFLPs (SphI, StuI, HapII, XhoI polymorphisms). The normal alleles were composed of 13 different RFLPs haplotypes; the most common among the Japanese population carrying normal alleles was haplotype 8 (bDEF1) (31.3%), the others being dispersed. The same haplotype 8 was the most frequent in the mutant alleles (44.4%), with seven further haplotypes. These findings revealed the striking variety of polymorphic haplotypes in the MPS IVA gene. By using these five kinds of RFLPs, we examined the theoretical informativity of haplotype analysis in heterozygote detection in nine unrelated MPS IVA families and ten unrelated normal families. All the members of the MPS IVA families studied were diagnosed as a patient, carrier, or noncarrier. We propose that prenatal diagnosis or family analysis in cases in which mutations have not been characterized is now feasible.  相似文献   
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