Unwillingness to cooperate with COVID-19 contact tracing in Japan.

OBJECTIVES: Contact tracing for COVID-19 relies heavily on the cooperation of individuals with authorities to provide information of contact persons. However, few studies have clarified willingness to cooperate and motivation to provide information for contact tracing. This study sought to describe willingness to cooperate and motivation to report contact persons for COVID-19 contact tracing among citizens in Japan, and to assess any associated sociodemographic factors. STUDY DESIGN: Cross-sectional study. METHODS: This was an online-based survey using quota sampling. Participants were asked about their willingness to cooperate in reporting contacts for COVID-19 contact tracing if they tested positive. Participants also responded to questions regarding their reasons for cooperating or not cooperating and provided sociodemographic data. Multiple logistic regression analysis was performed to clarify associations between sociodemographic factors and willingness to cooperate. RESULTS: This study included 2844 participants. The proportion of participants who were not willing to cooperate in reporting contacts was 27.6%, with their main reasons being concerns about causing trouble for the other person and being criticised for revealing their names. Willingness to cooperate was lower among men, young adults and those with an educational level less than a university degree. CONCLUSIONS: To improve the effectiveness of contact tracing, educational campaigns, such as reducing the fear and stigma associated with COVID-19, may be important. Furthermore, it is essential to understand that individuals may have contacts whom they do not wish to disclose to others and to be considerate when handling such situations.

Eradication of the commensal intestinal microflora by oral antimicrobials interferes with the host response to lipopolysaccharide.

The host components and commensal microorganisms of the intestinal microenvironment play roles in the development and maintenance of the host defence. Recent observations have suggested that toll-like receptors (TLRs) are involved in the recognition of innate immunity against intestinal microbes. However, little is known regarding the role of TLR in the maintenance of systemic host defence by intestinal microorganisms. We studied the expression and function of TLR4 and TLR2 on alveolar and peritoneal macrophages in mice after 3 weeks of oral administration of streptomycin and cefotaxime. After active treatment, the intestinal microorganisms were nearly completely eradicated, and the surface expression of TLR4 and TLR2 on the peritoneal macrophages was prominently downregulated. When the actively treated mice were challenged with lipopolysaccharide (LPS), a TLR4 ligand, the host response was markedly impaired. Our results suggest that the oral administration of antimicrobials downregulates the expression of surface TLR on the peritoneal macrophages and modulates the host immune responses against LPS by modifying the intestinal environment.

Subjective Well-Being Is Associated with Food Behavior and Demographic Factors in Chronically Ill Older Japanese People Living Alone.

OBJECTIVES: This study aimed to examine the relationships among subjective well-being, food and health behaviors, socioeconomic factors, and geography in chronically ill older Japanese adults living alone. DESIGN: The design was a cross-sectional, multilevel survey. A questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people living alone based on their proximity to a supermarket. Study recruitment was conducted with municipal assistance. MEASUREMENTS: To assess subjective well-being and food and health behaviors of respondents with disease, a logistic regression analysis was performed using stepwise variable analyses, adjusted for respondent age, socioeconomic status, and proximity to a supermarket. The dependent variable was good or poor subjective well-being. RESULTS: In total, 2,165 older people (744 men, 1,421 women) completed the questionnaire (63.5% response rate). Data from 737 men and 1,414 women were used in this study. Among people with a chronic disease, individuals with good subjective well-being had significantly higher rates than those with poor subjective well-being for satisfaction with meal quality and chewing ability, food diversity, food intake frequency, perception of shopping ease, having someone to help with food shopping, eating home-produced vegetables, preparing breakfast themselves, eating with other people, and high alcohol consumption. A stepwise logistic analysis showed that the factors strongly related to poor subjective well-being were shopping difficulty (men: odds ratio [OR] = 3.19, 95% confidence interval [CI], 1.94-5.23; P < 0.0001; women: OR = 2.20, 95% CI, 1.54-3.14; P < 0.0001), not having someone to help with food shopping (women: OR = 1.41, 95% CI, 1.01-1.97; P = 0.043), not preparing breakfast (women: OR = 2.36, 95% CI, 1.40-3.98; P = 0.001), and eating together less often (women: OR = 1.99, 95% CI, 1.32-3.00; P = 0.002). CONCLUSION: Subjective well-being of people with chronic diseases is associated with food intake and food behavior. The factors that affect poor subjective well-being in chronically ill older Japanese people living alone include food accessibility and social communication.

Association between Satisfaction with State of Health and Meals, Physical Condition and Food Diversity, Health Behavior, and Perceptions of Shopping Difficulty among Older People Living Alone in Japan.

OBJECTIVE: This study aimed to examine perceptions of shopping difficulty, and the relationships with satisfaction with state of health and meals, physical condition, food diversity and health behavior in older people living alone in Japan. DESIGN: A cross-sectional, multilevel survey was designed. The questionnaire was distributed by mail and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select the sample of older people living alone, by proximity to a supermarket. In total, 2,346 older people (827 men and 1,519 women) completed the questionnaire. MEASUREMENTS: The dependent variable was whether shopping was easy or difficult. A logistic regression analysis was performed, adjusting for age, socioeconomic status and proximity of residence to a supermarket using stepwise variable analyses. RESULTS: The response rate was 67.8%. Overall, 14.5% of men and 21.7% of women considered shopping difficult. The stepwise logistic analysis showed that the factors most strongly related to shopping difficulty were a subjective feeling of poor health (men: OR = 3.01, women: OR = 2.16) and lack of satisfaction with meals (men: OR = 2.82, women: OR = 3.69). Other related physical condition and dietary factors were requiring nursing care (men: OR = 3.69, women: OR = 1.54), a high level of frailty, measured using the frailty index score (women: OR = 0.36) and low food diversity score (men: OR = 1.84, women: OR = 1.36). CONCLUSION: The study found that older people's assessment of their shopping difficulty was related to satisfaction aspects, including a subjective feeling of poor health, and lack of satisfaction with meals, as well as physical condition. These have a greater influence on shopping difficulty than income in both sexes, and proximity to a supermarket in women.

"Eating Together" Is Associated with Food Behaviors and Demographic Factors of Older Japanese People Who Live Alone.

OBJECTIVE: This study aimed to examine the relationships between eating together and subjective health, frailty, food behaviors, food accessibility, food production, meal preparation, alcohol intake, socioeconomic factors and geography among older Japanese people who live alone. DESIGN: A cross-sectional, multilevel survey was designed. The questionnaire was distributed by post and self-completed by participants. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select a representative sample of older people who lived alone based on their proximity to a supermarket. Recruitment for the study was conducted with municipal assistance. MEASUREMENTS: A logistic regression analysis was performed that adjusted for the respondent's age, socioeconomic status and proximity to a supermarket using stepwise variable analyses. The dependent variable was whether the respondent ate together more or less than once a month. RESULTS: In total, 2,196 older people (752 men and 1,444 women) completed the questionnaire (63.5% response rate). It was found that 47.1% of men and 23.9% of women ate together less than once a month. Those who ate together less than once a month had a significantly lower rate of subjective health, food diversity and food intake frequency than those who ate together more often. A stepwise logistic analysis showed that the factors most strongly related to eating together less than once a month were not having any food shopping assistance (men: OR = 3.06, women: OR = 2.71), not receiving any food from neighbors or relatives (men: OR = 1.74, women: OR = 1.82), daily alcohol intake (women: OR = 1.83), frailty (men: OR = 0.48) and income (men: OR = 2.16, women: OR = 1.32). CONCLUSION: Eating together is associated with subjective health and food intake. Factors that affect how often older Japanese people who live alone eat together include food accessibility, daily alcohol intake, frailty and a low income.

Long-term detection of seasonal influenza RNA in faeces and intestine.

Some cases of seasonal influenza virus (human influenza A virus (IAV)/human influenza B virus (IBV)) are associated with abdominal symptoms. Although virus RNA has been detected in faeces, intestinal infection has not been clearly demonstrated. We aimed to provide evidence that IAV/IBV infects the human intestine. This prospective observational study measured virus RNA in faecal and sputum samples from 22 patients infected with IAV/IBV (19 IAV positive and three IBV positive). Nineteen patients were included in the analysis and were assigned to faecal IAV-positive and -negative groups. Virus kinetics were examined in faecal samples from an IAV-infected patient (patient 1) and an IBV-infected patient (patient 2). Finally, intestinal tissue from an IAV-diagnosed patient who developed haemorrhagic colitis and underwent colonoscopy was examined for the presence of replicating IAV (patient 3). Virus RNA was detected in faecal samples from 8/22 IAV/IBV-infected patients (36.4%). Diarrhoea occurred significantly more often in the faecal IAV-positive group (p 0.002). In patients 1 and 2, virus RNA became undetectable in sputum on days 7 and 10 after infection, respectively, but was detected in faeces for a further 2 weeks. Virus mRNA and antigens were detected in intestinal tissues (mucosal epithelium of the sigmoid colon) from patient 3. These findings suggest that IAV/IBV infects within the intestinal tract; thus, the human intestine may be an additional target organ for IAV/IBV infection.

Food Accessibility and Perceptions of Shopping Difficulty among Elderly People Living Alone in Japan.

OBJECTIVES: This aim of this study was to describe the association between shopping difficulty and food accessibility for elderly people living alone in Japan. DESIGN: A cross-sectoral, multilevel survey was designed to measure shopping difficulty from a food accessibility perspective. The questionnaire was distributed by mail. SETTING: The sample was drawn from seven towns and cities across Japan. PARTICIPANTS: A geographic information system was used to select the sample: it identified the proximity of elderly people living alone to a supermarket. In total, 2,028 elderly people (725 men and 1,303 women) responded to the questionnaire. MEASUREMENTS: The binary dependent variables were shopping is easy/shopping is difficult. A logistic regression analysis adjusting for age and area of residence and using stepwise variable analyses was performed. RESULTS: The response rate was 58.6%. Overall, 14.6% of elderly men and 21.7% of elderly women consider shopping difficult. The stepwise logistic analysis showed that the food accessibility factors strongly related to shopping difficulty are infrequent car use (women: OR = 6.97), walking difficulties (men: OR = 2.81, women: OR = 3.48), poor eyesight (men: OR = 2.26, women: OR = 1.75), not cooking lunch by oneself (men: OR = 1.63, women: OR = 1.72), not having anyone to help with food shopping (women: OR = 1.45) and living over 1 km away from a supermarket (men: OR = 2.30, women: OR = 2.97). CONCLUSION: The study concludes that elderly people's assessment of shopping difficulty is related to their food accessibility. Important food accessibility aspects include car or motorbike ownership, walking continuously for 1 km, poor eyesight, and having cooking skills and having someone to help with shopping. These physical activity restrictions have a greater influence on shopping difficulty than do either income or proximity to a supermarket.

Electron diffraction study on two-dimensional domain structure of L-DPPC monolayer.

A spatial variation in the two-dimensional crystal lattice orientation of L-DPPC monolayer on a hydrophobic substrate was observed by use of an electron microscope with diffraction and dark-field techniques. It is shown that the monolayer has a mosaic structure with domains, each of which consists of a region with a homogeneously oriented lattice of L-DPPC molecules. The domain structure of L-DPPC monolayer on a hydrophilic surface is also discussed.

Cloning and expression of the rubredoxin gene from Desulfovibrio vulgaris (Miyazaki F)--comparison of the primary structure of desulfoferrodoxin.

A gene encoding rubredoxin from Desulfovibrio vulgaris (Miyazaki F) was cloned and overexpressed in Escherichia coli. A 1.1-kilobase pair DNA fragment, isolated from D. vulgaris (Miyazaki F) by double digestion with SmaI and SalI, contained two genes, the rubredoxin gene (rub) and the desulfoferrodoxin gene (rbo) which was situated upstream of rub. The deduced amino acid sequence of desulfoferrodoxin was homologous to those from other strains and Cys residues that are responsible to bind irons were also conserved. The expression system for rub was constructed under the control of the T7 promoter in E. coli. The purified protein was soluble and had a characteristic visible absorption spectrum. Inductively coupled plasma-atomic emission analysis and electron paramagnetic resonance analysis of the recombinant rubredoxin revealed the presence of an iron ion in a distorted tetrahedral geometry that was the same as native D. vulgaris rubredoxin. In vitro NADH reduction analysis indicated that recombinant rubredoxin was active, and its redox potential was determined as -5 mV.

Inhibition of HIV-1 replication by targeting the Rev protein.

Human immunodeficiency virus type 1 (HIV-1) encodes two regulatory proteins, Tat and Rev. The Rev protein facilitates the transport of unspliced and singly-spliced RNA to the cytoplasm in infected host cells by binding to target RNA (Rev response element: RRE). A variety of approaches targeting Rev function, including gene therapy, have been developed that inhibit HIV-1 replication in cells cultured in vitro. This minireview summarizes the recent developments as well as our application of the Rev-binding element-based decoy approach using RNA-DNA chimera oligonucleotide modeling.

Nonsense mutations in the vpr gene of HIV-1 during in vitro virus passage and in HIV-1 carrier-derived peripheral blood mononuclear cells.

Long-term, persistent infection by HIV-1 is a prerequisite for the development of AIDS. However, little is known of the determinants required for HIV-1 to cause persistence. We have reported previously that persistent infection of a T cell line by a cytopathogenic strain of HIV-1 became increasingly likely with in vitro serial passage of the virus. DNA sequencing of the persistent strains revealed a nonsense mutation in the vpr gene in all isolates tested. Here, we report the development and use of a semi-quantitative PCR method to detect the vpr nonsense mutation within populations of virus. Our results show that vpr mutants also arise in cells during acute infection and increase progressively with serial passage of the virus. In addition, HIV-1-seropositive individuals were examined and found to carry the same vpr nonsense mutation at high frequency in virus-infected PBMC. These data are consistent with a mechanism of HIV-1 persistence in vivo and in vitro in which virus cytopathogenic potential is lost by the build up of nonsense mutations in vpr.

Positive feedback regulation of type I IFN genes by the IFN-inducible transcription factor IRF-7.

The interferon regulatory factor (IRF) family of transcription factors regulate the interferon (IFN) system, among which IRF-3 is involved in the virus-induced IFN-beta gene expression. Here we show that another member IRF-7 is critical for the IFN-alpha gene induction. Unlike the IRF-3 gene, the IRF-7 gene is induced by IFNs through activation of the ISGF3 transcription factor, and IRF-7 undergoes virus-induced nuclear translocation. In cells lacking p48, an essential component of IFN stimulated gene factor 3 (ISGF3), ectopic expression of IRF-7 but not IRF-3 can rescue the deficiency to induce IFN-alpha genes. These results indicate that IRF-7 is a key factor in the positive feedback regulation of IFN-alpha/beta production.

Demonstration of Borna disease virus RNA in peripheral blood mononuclear cells derived from Japanese patients with chronic fatigue syndrome.

CFS, a recently named heterogeneous disorder, is an illness of unknown etiology. The association of CFS with viral infections has been suggested. A common association between CFS and several viruses examined has not been confirmed. Here, we centered on the possible link between CFS and BDV infection. By nested RT-PCR followed by hybridization, BDV RNA was demonstrated as a clear signal in PBMCs in 3 out of 25 CFS patients. The amplified cDNA fragments were cloned and sequenced. A total of 16 clones were studied. Intra-patients divergencies of the p24 were 2-9%, 3-20%, and 3-11% in the deduced amino acids. Inter-patient divergencies among the 16 clones were 3-24%. Antibodies to recombinant BDV p24 protein were detected in 6 CFS patients including one carrying BDV RNA. Overall, these gave the prevalence of 32% (8/25) in Japanese CFS patients, suggesting that Japanese CFS is highly associated with active infection of BDV, or a related agent.

Demonstration of human Borna disease virus RNA in human peripheral blood mononuclear cells.

BDV naturally infects horses and sheep, and causes sporadic neurological disease. Serological evidence suggests an association of BDV, or a related virus, with specific psychiatric diseases in humans. Here, by using a nested RT-PCR technique, we demonstrate that human BDV RNA is present in the PBMC of psychiatric patients. In an examination of a total of 60 patients from 5 wards of a hospital in Japan, the detection rate differed within each ward, ranging from 8% to > 50% (37% on the average). Of particular note was the finding that the human derived BDV sequences, which included deleted forms in about 23% of the positive samples, were slightly different from those derived from horse BDV. These results suggest urgent consideration of the measures to be taken to cope with the effects of blood transfusion. In addition, the detection of a high level of BDV in the PBMC of patients will help our understanding of the pathogenesis in the disease.

Role of thymidine phosphorylase and dihydropyrimidine dehydrogenase in tumour progression and sensitivity to doxifluridine in gastric cancer patients.

This study was designed to investigate the role of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) on tumour progression and sensitivity to 5'-deoxy-5-fluorouridine (5'-DFUR). Tumour tissue was obtained from surgically resected samples from 93 patients with primary gastric cancer. Tumour TP and DPD expression levels were determined by the enzyme-linked immunosorbent assay (ELISA) system and compared with several clinicopathological factors and in vitro sensitivity to 5'-DFUR. DPD showed no correlation with any clinicopathological factors. However, the TP level was significantly correlated with the depth of tumour, lymphatic invasion and venous invasion. In comparison with 5'-DFUR sensitivity, there was a weak inverse correlation between the DPD level and the sensitivity to 5'-DFUR (r(s)=-0.361). Furthermore, the TP/DPD ratio showed a significant correlation with 5'-DFUR sensitivity (r(s)=0.634). In a subgroup of patients with postoperative 5'-DFUR administration, the survival rate was significantly better in patients with a high TP/DPD ratio (n=8) than in those with low TP/DPD ratio (n=14) (P=0.0140). These results suggest that sensitivity to 5'-DFUR is predictable by measurement of both TP and DPD levels.

Superior antitumour activity of S-1 in tumours with a high dihydropyrimidine dehydrogenase activity.

To elucidate the mechanism of the enhanced antitumour activity of S-1 (1 M tegafur, 0.4 M 5-chloro-2, 4-dihydroxypyridine, and 1 M potassium oxonate) in terms of the phosphorylation and degradation pathways of 5-fluorouracil (5-FU) metabolism, we investigated tumoral thymidylate synthase (TS) content, dihydropyrimidine dehydrogenase (DPD) activity, the TS inhibition rate (TS-IR), and 5-FU incorporated into RNA (F-RNA) in four human gastric cancer xenografts (MKN-28, MKN-74, GCIY and GT3TKB) and compared the results obtained with S-1 with those obtained with 5-FU and UFT (1 M tegafur, 4 M uracil). 5-FU was administered intraperitoneally (i.p.) to mice at a dose of 50 mg/kg, three times, on days 0, 4 and 8. S-1 and UFT were administered orally at doses of 10 and 24 mg/kg, respectively, once a day, for 9 consecutive days. Antitumour activity was evaluated as the maximum inhibition of tumour growth in each animal. S-1 showed a better antitumour activity than 5-FU and UFT in tumours with a high DPD activity (GCIY and GT3TKB). There were inverse correlations between the antitumour activity and both TS content and DPD activity in the 5-FU and UFT groups. However, no such correlations were observed in the S-1 group. In GCIY and GT3TKB xenografts, TS-IR was significantly higher in the S-1 group than in the 5-FU or UFT groups. In GT3TKB xenografts, the F-RNA level was significantly higher in the S-1 group than in the 5-FU or UFT groups. The superior cytotoxicity of S-1 appears to be attributable to both an increased inhibition of DNA synthesis and an enhanced blockade of RNA function against tumours with a high DPD activity.

Varied prevalence of Borna disease virus infection in Arabic, thoroughbred and their cross-bred horses in Iran.

Borna disease virus (BDV) naturally infects horses and sheep and induces progressive poliomeningoencephalomyelitis. Here, BDV recombinant proteins of the first open reading frame (ORF-I; coding for p40 nucleoprotein) and the second ORF-II (coding for p24 polymerase cofactor) were immunoblotted with plasma derived from 72 healthy (28 Arabic, 17 thoroughbred and 27 cross-bred) race horses at Tehran in Iran to detect anti-BDV antibodies. In addition, their peripheral blood mononuclear cells (PBMCs) were also examined for BDV RNA by a nested reverse transcriptase-polymerase chain reaction (RT-PCR) at ORF-II. The prevalence of BDV antibodies and/or RNA was 41.2% in Arabic, 23.5% in thoroughbred, and 33.3% in cross-bred horses, but only 17.9, 5.9, and 11.1% of them, respectively, showed positive signals for both BDV antibodies and RNA. Especially, cross-bred horses showed a higher prevalence for BDV RNA, which was detected only in females. In addition, significantly higher prevalence for BDV RNA was observed in Arabic males and thoroughbred females. The BDV prevalence did not increase with aging of the horse. Sequencing at the region of BDV derived from Iranian horses revealed a slight difference from those of Japanese horse- and European horse-derived BDVs even in the amino acid residues, although those in the three groups of Iranian horses were quite similar. Thus, the varied prevalence of BDV was observed with the horse strain or sex in Iranian horses, although BDV sequences were very similar among all three groups in Iran compared with those derived from other countries.

Serial passage of human immunodeficiency virus type 1 generates misalignment deletions in non-essential accessory genes.

Human immunodeficiency virus type 1 (HIV-1) derived from an infectious molecular clone pNL432 was extensively passaged in tissue culture by repeated rounds of acute infection. We previously showed the natural occurrence of a nonsense mutation in the vpr gene during continued passage of this virus. In this report, we show that two forms of large deletions (561 and 518 base pairs containing short direct repeats at the deletion junctions) occur after passage 50 in the region that spans the vif and vpr open reading frames. One model to explain the occurrence of these deletion regions is that such mutations result from misalignment of the growing point at a limited number of nucleotide positions. Infection of CD4+ T-cells with a recombinant HIV-1 construct containing the same vif to vpr deletion showed virtually no cytopathogenic phenotype. Thus, misalignment deletions at non-essential accessory genes of HIV-1 might be induced during replication, which result in the generation of virus with a low cytopathogenic potential.

Synthesis and blood compatibility evaluation of segmented polyurethanes based on cholesterol and phosphatidylcholine analogous moieties.

New segmented polyurethanes based on cholesterol and phosphatidylcholine analogous moieties were synthesized. The soft segments used in this study were the poly(butadiene), poly(isoprene) or hydrogenated poly(isoprene) glycols; the hard segments of these segmented polyurethanes were composed of 4,4'-methylenediphenyl diisocyanate, 2-[bis(2-hydroxyethyl)methylammonio]ethyl 5-cholesten-3 beta-yl phosphate and 1,4-butanediol. The blood compatibilities of synthesized segmented polyurethanes were evaluated by platelet-rich plasma contact studies and scanning electron microscopy observation using glass as the reference. The results show that the blood compatibilities of the synthesized segmented polyurethanes have great difference between the glass contact side and air exposed side for the same cast films. Generally, the hydrogenated poly(isoprene)-based segmented polyurethane is the best surface in terms of platelet adhesion, and the morphology of adhered platelets undergoes the lowest degree of variation among the segmented polyurethanes investigated in this study.

Crystallization and preliminary X-ray diffraction studies of a flavoprotein, FP390, from a luminescent bacterium, Photobacterium phosphoreum.

A flavoprotein, FP390, obtained from a luminescent bacterium, Photobacterium phosphoreum, in the purification of luciferase has been crystallized by the vapor-diffusion procedure. Crystals obtained from polyethylene glycol 4000 solutions, whose X-ray photographs show powder diffraction patterns, were unsuitable for further crystallographic work. However, tetragonal crystals grown from potassium phosphate solution well diffracted X-rays beyond 3 A resolution. The space group of this crystal is P4(1)22 or P4(3)22 with unit-cell dimensions of a = b = 76.8 and c = 241 A. Assuming two or three molecules in an asymmetric unit, the value for the crystal volume per unit molecular mass, Vm, is calculated as 3.3 or 2.2 A3/Da, respectively. A total of 13,555 independent reflections for the native crystal was collected up to 3 A resolution using a Weissenberg camera attached to the synchrotron radiation source, the merging R factor being 0.077 for 79,335 measurements.