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71.
To clarify whether long‐term oral ingestion of aluminum (Al) can increase tau aggregation in mammals, we examined the effects of oral Al administration on tau accumulation, apoptosis in the central nervous system (CNS) and motor function using tau transgenic (Tg) mice that show very slowly progressive tau accumulation. Al‐treated tau Tg mice had almost twice as many tau‐positive inclusions in the spinal cord as tau Tg mice without Al treatment at 12 months of age, a difference that reached statistical significance, and the development of pretangle‐like tau aggregates in the brain was also significantly advanced from 9 months. Al exposure did not induce any tau pathology in wild‐type (WT) mice. Apoptosis was observed in the hippocampus in Al‐treated tau Tg mice, but was virtually absent in the other experimental groups. Motor function as assessed by the tail suspension test was most severely impaired in Al‐treated tau Tg mice. Given our results, chronic oral ingestion of Al may more strongly promote tau aggregation, apoptosis and neurological dysfunction if individuals already had a pathological process causing tau aggregation. These findings may also implicate chronic Al neurotoxicity in humans, who frequently have had mild tau pathology from a young age.  相似文献   
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The therapeutic efficacy of short-term treatment with a 1% cream of lanoconazole, a new imidazole antimycotic agent, in comparison with that of a 1% cream of terbinafine was evaluated in the guinea pig model of tinea pedis. Each agent was topically applied once a day for 3 or 7 consecutive days, starting on day 10 postinfection, and a culture study was conducted on day 5 after the last treatment with each agent. The 1% cream of lanoconazole was as highly effective as the 1% cream of terbinafine in terms of eradicating the fungi from the infected feet.  相似文献   
74.
Background Comparative genomic hybridization (CGH) analysis of pancreatic cancer has been done exclusively for surgical and autopsy specimens, because of the difficulty of tissue sampling without surgery. To overcome this difficulty, we applied CGH technology to cells obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA).Methods In the present study, we performed EUS-FNA for 17 patients with pancreatic cancer before surgery. Tumor cells were selected by microdissection. DNA was extracted from the cells and amplified by degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR). Then CGH was carried out.Results In the 15 patients with tubular adenocarcinoma, the most common loci of gains (including amplification) were 5p, 8q, and 20q (60% of the patients); and 1q, 7p, and 12p (27%). The most frequent losses were 17p (73%); 9p, 18q, and 19p (47%); and 8p (33%). These findings were similar to our previously reported data. Both of the patients with acinar cell carcinoma showed gains of 2q and 5p, and losses of 1p, 9p, 9q, 11p, 11q, 14q, 17p, 17q, and 18q.Conclusions The results of this study suggest that comprehensive genetic analysis is possible for EUS-FNA biopsy specimens, with a combination of microdissection and DOP-PCR. This analytical strategy will enable us to evaluate the biological characteristics of pancreatic cancer before treatment.  相似文献   
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76.
Objective This study assessed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses to the BNT162b2 mRNA vaccine in Japanese healthcare workers. Methods In this prospective cohort study, participants received two doses of the BNT162b2 mRNA vaccine on days 0 and 21 and provided blood for anti-SARS-CoV-2 antibody testing before the first vaccine and on days 21 and 35 after vaccination. Anti-spike protein immunoglobulin G (S-IgG) was measured using Abbott and Fujirebio chemiluminescent immunoassays. Patients One hundred healthcare workers (median age: 39 years old, interquartile range: 30-48 years old), including 6 who had been previously infected with SARS-CoV-2 and 3 individuals taking immunosuppressive drugs, participated in the study. Results The S-IgG antibody titers (AU/mL) measured using both the Abbott and Fujirebio assays increased significantly (p<0.001) over time, both with a prevalence of 100% at 35 days after the first vaccination. The multivariate log-normal linear regression analysis indicated the effect of immunosuppressant medication using both the Abbott (p=0.013) and Fujirebio (p=0.039) assays on S-IgG levels after complete vaccination. Pearson''s correlation coefficient between the Abbott and Fujirebio S-IgG results in all 300 samples collected before and after vaccination and 50 positive controls from patients with coronavirus disease 2019 were 0.963 [95% confidence interval (CI): 0.954-0.970, p<0.001] and 0.909 (95% CI: 0.845-0.948, p<0.001), respectively. Conclusion The BNT162b2 mRNA vaccine was effective at increasing S-IgG levels in Japanese immunocompetent healthcare workers. The Fujirebio S-IgG assay showed high diagnostic accuracy, using the Abbott S-IgG assay as the reference test.  相似文献   
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78.
To investigate the relationship between the pathogenicity of Newcastle disease virus and the structure of viral proteins, two typical strains were sampled from each of three groups of different pathogenicities and these six strains were compared for protein structure by sizing peptides generated by partial digestion with Staphylococcus aureus V8 protease and chymotrypsin. These digests yielded closely similar peptide patterns for the internal polypeptides L and NP, whereas those of the glycoproteins HN and F showed apparent variations which appeared to be specific for the individual groups. Although not as significant as in the glycoproteins, group-dependent variations were also detectable with the M protein. These results suggest that the external proteins might undergo considerable changes whereas the internal proteins would be highly stable and that there is a definite correlation between such changes in the external proteins and the pathogenicity of the virus.  相似文献   
79.
The effects of dopamine receptor agonists on electrically evoked dopamine release from slices of nucleus accumbens were compared with the effects on release from striatal slices in rats. Apomorphine, which has equal potency at the dopamine D2 and D3 receptors, reduced the evoked dopamine release from both regions to the same extent (ED50, 0.42 μM for nucleus accumbens; ED50, 0.46 μM for striatum). Quinpirole of 7-[3H]hydroxy-N,N-di-n-propyl-2-aminotetralin (7-OHDPAT), which are much more potent at the D3 receptor than at the D2 receptor, reduced the evoked dopamine release from the nucleus accumbens (ED50, 0.12 μM for quinpirole; 0.02 μM for 7-OHDPAT) much more than the release from the striatum (ED50, 1.6 μM for quinpirole; 0.55 μM for 7-OHDPAT). These results suggest that the contribution of D3 receptors in nucleus accumbens to regulate dopamine release from dopamine nerve terminals is much greater than that in striatum.  相似文献   
80.
Anti-human factor IX monoclonal antibody, A-5 (Mab A-5), has been widely used in structure-function studies for factor IX. Mab A-5 recognizes the catalytic domain of human factor IX (FIX). Regions important for Mab A-5 binding have previously been localized to the amino terminus of the heavy chain of factor IX, encompassing amino acid residues 181-310 [Blood (74) 971]. We have selected 20 positions in this region for alanine-scanning mutagenesis. We found that Mab A-5 failed to react with the recombinant factor IX mutants with substitutions at positions 228 and 252. Mab A-5 also reacted to a lesser extent to FIXD276A (factor IX with alanine substitution for aspartic acid at residue 276) and FIXK201A/D203A (double alanine substitutions at residues 201 and 203). The apparent dissociation rate constants (K(D)) in binding Mab A-5 were 6.0 x 10(-9), 1.4 x 10(-8) and 2.0 x 10(-8) M, for wild-type FIX, FIXK201A/D203A and FIXD276A, respectively. The increased K(D) values of the two FIX mutants are mainly owing to the increased dissociation rates. These affected residues constitute a surface opposite from the factor VIIIa binding surface. We conclude that the epitope for Mab A-5 is on a surface composed of residues 228, 252, 276, and 201 or 203. This surface, which may not be important for factor VIII binding, contains a strong antigenic region on factor IX.  相似文献   
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