Difference in CD22 molecules in human B cells and basophils

OBJECTIVE: CD22 is believed to be restricted to normal and neoplastic B cells. Human basophils were found to express CD22 molecules. Among the antibodies against CD22, Leu14, which recognized the ligand binding domain, reacted to basophils, and B3 and 4KB128, which recognized the amino terminus side and carboxy terminus side of the ligand binding epitope, respectively, did not. To clarify the difference of CD22 antigenicity in human B cells and basophils, we investigated RNA sequence and structures of CD22 molecules. MATERIALS AND METHODS: Purified B cells and basophils were obtained from normal human volunteers by using a MACS magnetic cell sorting system and anti-CD19 and anti-Fc epsilon R1 antibodies, respectively. RT-PCR and sequencing of CD22 mRNA were performed in the exons 3 to 8. Western blotting analysis of CD22 was also performed. RESULTS: The sequence of CD22 mRNA extracted from the basophils was the same as that of B cells in exons 3 to 8 (epitopes recognized by Leu14, B3, and 4KB128 were translated from exons 4 and 5). Reduced CD22 peptide extracted from the basophils reacted to Leu14 as well as B3 and 4KB128, and the molecular size of the reduced and nonreduced products was 130 kDa as expected. CONCLUSION: Disulfide bonds and the resulting 3D conformation of the CD22 molecules may have important roles in the difference of antigenicity of CD22 beta in B cells (CD22 beta 1) and basophils (CD22 beta 2). The difference in molecular structure surrounding the ligand-binding domain of CD22 may imply a specialization of the conformational forms of CD22 according to the ligand isoforms.     

Risk factors for heavy burden among family caregivers in a rural town in Hokkaido

OBJECTIVE: The present study was conducted in order to investigate risk factors for heavy burden of family caregivers. STUDY DESIGN: Cross-sectional study. PARTICIPANTS: 51 pairs of the frail elderly and their family caregivers in one town in Hokkaido. RESULTS: Compared to those with a lighter burden, family caregivers with heavier burden looked after the frail elderly with more behavior disturbances due to dementia. They cared for the elderly longer and had less time to go out without accompanying their charges than less burdened caregivers. On the other hand, the elderly had similar activities of daily living and degree of need of care between the two groups. In addition, physical caring time did not differ between the two groups. These findings suggest that the psychological burden may be more important than the physical burden. In addition, caregivers used only 30-40% of services they had the right to use with long-term care insurance. These findings suggest that more convenient services for users should be provided.     

Air-stable, storable, and highly efficient chiral zirconium catalysts for enantioselective Mannich-type, aza Diels-Alder, aldol, and hetero Diels-Alder reactions

For the synthesis of optically active compounds, chiral catalysts have attracted much attention because large quantities of optically active molecules can be prepared from a small amount of a chiral source. However, many chiral catalysts are often unstable in air (oxygen) and/or in the presence of water. This is especially the case in chiral Lewis acid catalysis, because most Lewis acids are air- and moisture-sensitive. Therefore, many catalysts are prepared in situ in an appropriate solvent just before use, and they cannot be stored for extended periods. We have developed air-stable, storable, and highly efficient chiral zirconium Lewis acids. The catalysts promoted asymmetric Mannich-type, aza Diels-Alder, aldol, and hetero Diels-Alder reactions efficiently with high enantioselectivities. A key to stabilizing the catalysts is an appropriate combination of chiral zirconium Lewis acids with molecular sieves, and the zirconium-molecular sieves-combined catalysts can be stored for extended periods in air at room temperature without loss of activity. Moreover, it has been demonstrated that the catalysts can be recovered and reused.     

Two patients treated with pegylated interferon/ribavirin/telaprevir triple therapy for recurrent hepatitis C after living donor liver transplantation

It is difficult to use protease inhibitors in patients with recurrent hepatitis C virus (HCV) infection after liver transplantation (LT) due to interaction with immunosuppressive drugs. We report our experience with two patients treated with telaprevir (TVR) combined with pegylated interferon/ribavirin (PEG IFN/RBV) for recurrent HCV genotype 1 infection after LT. The first was a 63‐year‐old man with HCV‐related liver cirrhosis, who failed to respond to IFN‐β plus RBV after LT. Treatment was switched to PEG IFN‐α‐2b plus RBV and TVR was started. The donor had TT genotype of interleukin (IL)‐28 single nucleotide polymorphisms (SNP) (rs8099917). The recipient had TT genotype of IL‐28 SNP (rs8099917). Completion of 12‐week triple therapy was followed by PEG IFN‐α‐2b plus RBV for 36 weeks. Finally, he had sustained viral response. The second was a 70‐year‐old woman with HCV‐related liver cirrhosis and hepatocellular carcinoma. She failed to respond to PEG IFN‐α‐2b plus RBV after LT, and was subsequently switched to PEG IFN‐α‐2b/RBV/TVR. Genotype analysis showed TG genotype of IL‐28 SNP for the donor, and TT genotype of IL‐28 SNP for the recipient. Serum HCV RNA titer decreased below the detection limit at 5 weeks. However, triple therapy was withdrawn at 11 weeks due to general fatigue, which resulted in HCV RNA rebound 4 weeks later. Both patients were treated with cyclosporin, starting with a small dose to avoid interactions with TVR. TVR is a potentially suitable agent for LT recipients who do not respond to PEG IFN‐α‐2b plus RBV after LT.     

Association of Periodontal Diseases and Liver Fibrosis in Patients With HCV and/or HBV infection

Background:

Periodontal disease and systemic health are closely associated. However, there is no data supporting the association between periodontal disease and patients with liver diseases associated with hepatitis C virus (HCV) and/or hepatitis B virus (HBV) infection.

Objectives:

The aim of this study was to evaluate the association between periodontitis and progression of liver diseases in patients with HCV and/or HBV infection.

Patients and Methods:

In this retrospective study, 351 patients with HCV- and/or HBV-related liver diseases underwent screening for periodontal disease using the Salivaster® salivary occult blood test from February 2010 to June 2014. Furthermore, we examined the prevalence of fimbrillin (fimA) genotype of Porphyromonas gingivalis (P. gingivalis) in 28 HCV-infected patients visited at our hospital between January 2013 and June 2014. P. gingivalis with fimA genotype with types I to V was further detected using a PCR method.

Results:

Of 351 patients, 76 patients (group 1) had a strong positive result for salivary occult blood test and 275 patients (group 2) had weak positive or negative test results. Significant factors between the groups were obesity, level of AST, ALT, LDH, ALP, Alb, D.Bil, T.cho, AFP, platelets (Plt), IRI, HOMA-IR, current interferon (IFN) treatment and the daily frequency of tooth brushing. Between-groups analysis indicated that total protein (T.pro) level and liver fibrosis were significant factors. According to multivariate analysis, five factors were associated with periodontal disease as Plt count below 80000, brushing teeth only once a day, current IFN treatment, aged 65 years or older and obesity. The adjusted odds ratios for these five factors were 5.80, 3.46, 2.87, 2.50 and 2.33, respectively, and each was statistically significant. Twenty-eight saliva specimens had positive results for P. gingivalis with fimA genotype types I to V. The prevalence of fimA genotype II was higher in 14 patients with liver cirrhosis or a history of hepatocellular carcinoma treatment (group B, 50.00%) than 14 patients with only hepatitis C (group A, 21.43%).

Conclusions:

Periodontitis might be associated with progression of viral liver disease; hence, controlling oral disease is essential for the prevention and management of liver fibrosis.     

Learning predator promotes coexistence of prey species in host-parasitoid systems

Ecological theory suggests that frequency-dependent predation, in which more common prey types are disproportionately favored, promotes the coexistence of competing prey species. However, many of the earlier empirical studies that investigated the effect of frequency-dependent predation were short-term and ignored predator-prey dynamics and system persistence. Therefore, we used long-term observation of population dynamics to test how frequency-dependent predation influences the dynamics and coexistence of competing prey species using insect laboratory populations. We established two-host-one-parasitoid populations with two bruchid beetles, Callosobruchus chinensis and C. maculatus, as the hosts and the pteromalid wasp Anisopteromalus calandrae as their common parasitoid. When the parasitoid was absent, C. chinensis was competitively excluded in ～20 wk. Introducing the parasitoid greatly enhanced the coexistence time to a maximum of 118 wk. In the replicates of long-lasting coexistence, the two host species C. maculatus and C. chinensis exhibited periodic antiphase oscillations. Behavioral experiments showed frequency-dependent predation of A. calandrae that was caused by learning. Females of A. calandrae learned host-related olfactory cues during oviposition and increased their preference for the common host species. Numerical simulations showed that parasitoid learning was the essential mechanism that promoted persistence in this host-parasitoid system. Our study is an empirical demonstration that frequency-dependent predation has an important role in greatly enhancing the coexistence of prey populations, suggesting that predator learning affects predator-prey population dynamics and shapes biological communities in nature.