Cloning and characterization of the cDNA encoding the HA protein of a hemagglutination-defective measles virus strain

cDNA clones corresponding to the mRNA for the hemagglutinin of the hemagglutination-defective strain AK-1 of measles virus were isolated and characterized. Compared with the prototype Edmonstron strain, 60 nucleotide substitutions that resulted in 18 amino acid changes were detected. An additional potential N-linked glycosylation site was added by point mutation, which was supported by the observation that the hemagglutinin of the AK-1 strain was stained more heavily after NaDodSO₄PAGE and periodic acid-Schiff (PAS) staining than the Edmonston strain. Computer-assisted analysis revealed that three reverse turns in the secondary structure had disappeared in the hemagglutinin of the AK-1 strain. Moreover, one of these structural changes occurred in the closely glycosylated region at amino acid residues 168–240, which appeared to be a biologically important functional domain. The isoelectric point calculated from the predicted amino acid sequence became about 1 pH unit more basic in the AK-1 strain than the Edmonston strain. This present study is the first sequence analysis of the hemagglutinin gene in a hemagglutination-defective strain of the measles virus.     

Loss of heterozygosity on chromosome 9q22.3 in microdissected basal cell carcinomas around the Semipalatinsk Nuclear Testing Site, Kazakhstan

A high incidence of skin cancers has been noted around the Semipalatinsk Nuclear Testing Site (SNTS) in Kazakhstan. Recently, basal cell carcinoma (BCC) susceptibility genes, human homolog of the Drosophila pathed gene (PTCH), and the xeroderma pigmentosa group A-complementing gene (XPA), have been cloned and localized on chromosome 9q22.3. To clarify the effect of low-dose irradiation on the occurrence of BCC, we used microdissection and polymerase chain reaction to identify loss of heterozygosity (LOH) at 9q22.3 using BCC samples obtained from this region. Ten Japanese samples were analyzed as controls. LOH with at least 1 marker was identified in 5 of 14 cases from around SNTS, whereas only 1 case with 1 marker was identified among the 10 Nagasaki cases. The total number of LOH alleles from SNTS (8 of 45) was significantly higher than the number from Nagasaki (1 of 26) (P = 0.03). The higher incidence of LOH on 9q22.3 in BCC from around SNTS suggests involvement of chronic low-dose irradiation by fallout from the test site as a factor in the cancers.     

Prevention of endotoxin shock by an antibody against leukocyte integrin {beta}2 through inhibiting production and action of TNF

Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans.     

Genetic contribution of tumor necrosis factor (TNF)-alpha gene promoter (-1031, -863 and -857) and TNF receptor 2 gene polymorphisms in endometriosis susceptibility

PROBLEM: Tumor necrosis factor (TNF)-alpha is a major cytokine involved in inflammatory and immune function. The aim of this study was to investigate whether polymorphisms at positions -1031, -863 and -857 in the TNF gene promoter region (TNFA) and TNF receptor type 2 gene (TNFR2) are responsible in part for genetic susceptibility to endometriosis. METHODS OF STUDY: TNFA and TNFR2 polymorphisms were determined in 123 patients with endometriosis and 165 fertile healthy women by the polymerase chain reaction (PCR) - preferential homoduplex formation assay and PCR-restriction fragment length polymorphism, respectively. RESULTS: The frequency of the TNFA-U01 haplotype was increased significantly in patients with endometriosis compared with controls (P = 0.045, OR = 1.45). The TNFA-U01 haplotype was strongly associated with HLA-B*0702. No difference was found in TNFR2 polymorphism between patients and controls. CONCLUSION: Our results indicated that TNFA promoter polymorphism was associated with susceptibility to endometriosis. However, this association was not independent of HLA-class I polymorphisms.     

Effects of focus on working memory

Effects of focus on a target word during performance of the reading span test (RST) were investigated. A focus word in the sentence was defined as the most critical word with a core meaning to integrate the sentence. Two kinds of RST were compared. One was focus-RST (F-RST) in which the target word to be maintained was a focus word of the sentence. The other was a non-focus-RST (NF-RST) in which the target word was not a focus word of the sentence, although the sentence did contain a focus word. Results showed that RST scores were found to be higher for F-RST than for NF-RST. Moreover, the effect of focus was proved to be dominant for low span subjects. Intrusion errors also increased in NF-RST. Sentence length effect, however, was not found. The results showed that low span subjects had severe deficits in making and updating the focus, which is critical for sentence comprehension.     

Distribution of 5-hydroxytryptamine (5HT) in tissue of a mutant mouse deficient in mast cell (W/W v ). Demonstration of the contribution of mast cells to the 5HT content in various organs

The content of 5-hydroxytryptamine (5HT) in various tissues of mutant mouse (W/W ^v) deficient in mast cells and of control mouse (+/+) was determined by high performance liquid chromatography. The depletion of mast cells in the mutant mouse (W/W ^v) was expected to cause a decrease in the 5HT content. In the control mice, 5HT was most densely accumulated in the lung (9.66±5.23 g/g). Large intestine (6.40±2.61 g/g) and stomach (6.10±2.14 g/g) followed the lung in the rating of the 5HT content. The 5HT content ofW/W ^v mice was only 23.4% and 4.1% that of the control in the stomach (p<0.01) and the skin (p<0.01), respectively. The results were consistent with the expectation. In other organs (small intestine, caecum, large intestine, brain, lung, blood and salivary gland), the difference between theW/W ^v and normal mice was not statistically significant. The difference in the 5HT content of the stomach between the two genotypes was 4.67 g/g and was much larger than the 5HT content (0.49g/g) of normal mouse skin. With regard to the relatively small number of mast cells present in the stomach, the great difference in the 5HT content in the stomach between the two genotypes cannot be explained by the loss of mast cells. Hence, besides mast cells other cells may contribute to the high 5HT content of the stomach.This work was supported in part by grants from Takeda Science Foundation (1982), from the Ministry of Education, Science and Culture of Japan (Grant-in-Aid for Special Project Research. 1981–83) and from National Center of Nervous, Mental and Muscular Disorders (NCNMMD) of the Ministry of Health and Welfare, Japan (1981–83).To whom correspondence should be addressed     

Cytoplasmic aggregation of TRAF2 and TRAF5 proteins in the Hodgkin-Reed-Sternberg cells

We previously reported that ligand-independent signaling by highly expressed CD30 in Hodgkin-Reed-Sternberg (H-RS) cells is responsible for constitutive activation of NF-kappa B. In the present study, we characterize the intracellular localization of tumor necrosis factor (TNF) receptor associated factor (TRAF) proteins in H-RS cells. Confocal immunofluorescence microscopy of cell lines derived from H-RS cells and HEK293 transformants highly expressing CD30 revealed aggregation of TRAF2 and TRAF5 in the cytoplasm as well as clustering near the cell membrane. In contrast, TRAF proteins were diffusely distributed in the cytoplasm in cell lines unrelated to Hodgkin's disease (HD) and control HEK293 cells. Furthermore, the same intracellular distribution of TRAF proteins was demonstrated in H-RS cells of lymph nodes of HD, but not in lymphoma cells in lymph nodes of non-Hodgkin's lymphoma. Dominant-negative TRAF2 and TRAF5 suppressed cytoplasmic aggregation along with constitutive NF-kappa B activation in H-RS cell lines. Confocal immunofluorescence microscopy also revealed co-localization of IKK alpha, NIK, and I kappa B alpha with aggregated TRAF proteins in H-RS cell lines. These results suggest involvement of TRAF protein aggregation in the signaling process of highly expressed CD30 and suggest they function as scaffolding proteins. Thus, cytoplasmic aggregation of TRAF proteins appears to reflect constitutive CD30 signaling which is characteristic of H-RS cells.     

Text comprehension and individual differences in working memory: the different contributions of the storage and the retrieval processing

The present study addressed the relationship between an individual difference in the reading span test (RST) and the performance in text comprehension with respect to storage and retrieval systems. In Experiment 1, an effect of the serial recall task on performance in text comprehension was compared between high and low RST score groups. In Experiment 2, an effect of the word fluency task on performance in text comprehension of two groups was investigated. The results of both experiments showed that the performance in text comprehension of the low RST score group was impaired when the serial recall task was the secondary task; in contrast, the performance of the high RST score group was influenced when the word fluency task was used. The results suggested that the high RST score group comprehended text not only by using a temporary storage system but also by using a retrieval system efficiently.     

Favorable efficacy of long-term lamivudine therapy in patients with chronic hepatitis B: an 8-year follow-up study

The long-term efficacy of lamivudine therapy in patients with hepatitis B virus (HBV) infection is still not clear. In this study, 20 non-cirrhotic Japanese patients infected with HBV received lamivudine therapy for more than 1 year and were followed for a median period of 8.5 years (range, 6.7-8.7 years). The rates of HBe antigen (HbeAg) negative, HBV-DNA undetectable, and alanine aminotransferase (ALT) normal level at the start of lamivudine were 55%, 25%, and 20% and 85%, 80%, and were 80%, respectively, at the last visit, including patients who received additional treatment. The values at the last visit tended to and were significantly higher than those at the start. The values improved at the last visit regardless of the emergence of YMDD motif mutant and continuation of lamivudine. YMDD mutant and biochemical relapse with mutant virus (breakthrough hepatitis) appeared in 65% and 45% during follow-up, respectively, but severe breakthrough hepatitis occurred in only 5%. Furthermore, 80% of patients who received additional treatment for breakthrough hepatitis, regardless of continuation of lamivudine, were ALT normal level at the last visit, in contrast to 25% untreated. HBsAg clearance occurred in two patients of the discontinuous lamivudine group with non-vertical transmission, who were relatively young. One was infected with HBV genotype C with breakthrough hepatitis and the other had no YMDD mutant and was infected with genotype D, a rare type in Japan. None developed cirrhosis or hepatocellular carcinoma (HCC) during follow-up. Our results suggest that long-term lamivudine therapy improves long-term prognosis, especially when additional treatment for breakthrough hepatitis is used.