Clinical Features and Treatment of Patients Infected With SARS-CoV-2 Omicron Variant While Hospitalized Due to Stroke: A Single Center Study in Japan.

BACKGROUND AND OBJECTIVE: In December 2019, COVID-19 spread rapidly across the globe. Throughout the pandemic, SARS-CoV-2 repeatedly mutated, transitioning from the alpha variant to the omicron variant. The severity and mortality of COVID-19 have been linked to age, sex, and the presence of underlying diseases (respiratory, cerebrovascular, cardiovascular, metabolic, and immune diseases, as well as cancer). The clinical features of patients infected with COVID-19 following a stroke, however, are fully unknown. Therefore, it is significant to explore the appropriate treatment for these patients based on their clinical features. METHODS: Of the 6175 patients who visited Asahi Hospital (Tokyo, Japan) between November 2022 and February 2023, 206 were admitted. Of these 206 patients, the 44 that contracted COVID-19 while hospitalized for strokes were retrospectively analyzed. RESULTS: Six (13.6%) of these patients died; four expired due to coagulopathy associated with ischemic heart failure and recurrent ischemic cerebrovascular disease. The mean D-dimer level increased to 3.53 in the deceased patients, while it was 1.64 in all patients. The platelet count was low in three of the deceased patients, while it was high in two patients. The severity of COVID-19 was significantly correlated with a high modified Rankin Scale (mRS) score and a high National Institute of Health Stroke Scale (NIHSS) score. The timing of vaccination is inversely correlated with COVID-19 severity. CONCLUSION: Patients with COVID-19 after a stroke have high mortality rates due to coagulopathy. Stroke patients with high mRS scores and high NIHSS scores are more likely to develop severe COVID-19. Anticoagulant therapy should be administered to COVID-19 patients with high mRS scores following a stroke.

Association between dysphagia risk and sleep quality in community-dwelling older adults: A cross-sectional study.

Objectives: Exploring the effects of swallowing function on sleep quality could provide valuable insights into the potential impact of reduced swallowing function on sleep. However, pertinent studies are limited. Therefore, this study aimed to investigate the relationship between dysphagia risk and sleep health in community-dwelling older adults. Methods: Data for this cross-sectional study were obtained from the Shizuoka and Daiko studies conducted as part of the Japan Multi-Institutional Collaborative Cohort Study. Information on demographics, overall lifestyle, dysphagia risk, as well as sleep quality, duration, satisfaction, and regularity, was obtained using a self-administered questionnaire. Dysphagia risk and sleep quality were assessed using the Dysphagia Risk Assessment Questionnaire for the Community-dwelling Elderly and the Japanese version of the Pittsburgh Sleep Questionnaire Index, respectively. Multivariate logistic regression, adjusted for covariates, was employed to assess the association between dysphagia risk and sleep health. Results: Among the 3058 participants (1633 males, 1425 females) aged ≥60 years, 28.0 % exhibited dysphagia risk, and 19.1 % reported poor sleep quality. Those with dysphagia risk were more likely to experience poor sleep quality than those without dysphagia risk. In male participants, dysphagia was significantly associated with poor sleep quality, unsatisfactory sleep, and sleep irregularity, but was not significantly associated with unsatisfactory or irregular sleep in female participants. The Japanese version of the Pittsburgh Sleep Questionnaire Index components-subjective sleep quality, sleep latency, sleep disturbances, and daytime dysfunction-were associated with dysphagia risk in both sexes. Conclusions: Dysphagia risk is associated with sleep quality in older individuals in Japan. Thus, preserving swallowing function may contribute to enhancing sleep quality.

Crystal structures of complexes of vitamin D receptor ligand-binding domain with lithocholic acid derivatives.

The secondary bile acid lithocholic acid (LCA) and its derivatives act as selective modulators of the vitamin D receptor (VDR), although their structures fundamentally differ from that of the natural hormone 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3)]. Here, we have determined the crystal structures of the ligand-binding domain of rat VDR (VDR-LBD) in ternary complexes with a synthetic partial peptide of the coactivator MED1 (mediator of RNA polymerase II transcription subunit 1) and four ligands, LCA, 3-keto LCA, LCA acetate, and LCA propionate, with the goal of elucidating their agonistic mechanism. LCA and its derivatives bind to the same ligand-binding pocket (LBP) of VDR-LBD that 1,25(OH)2D3 binds to, but in the opposite orientation; their A-ring is positioned at the top of the LBP, whereas their acyclic tail is located at the bottom of the LBP. However, most of the hydrophobic and hydrophilic interactions observed in the complex with 1,25(OH)2D3 are reproduced in the complexes with LCA and its derivatives. Additional interactions between VDR-LBD and the C-3 substituents of the A-ring are also observed in the complexes with LCA and its derivatives. These may result in the observed difference in the potency among the LCA-type ligands.

Gemstone spectral imaging: determination of CT to ED conversion curves for radiotherapy treatment planning.

The monochromatic images acquired by Gemstone spectral imaging (GSI) mode on the GE CT750 HD theoretically determines the computed tomography (CT) number more accurately than that of conventional scanner. Using the former, the CT number is calculated from (synthesized) monoenergetic X-ray data. We reasoned that the monochromatic image might be applied to radiotherapy treatment planning (RTP) to calculate dose distribution more accurately. Our goal here was to provide CT to electron density (ED) conversion curves with monochromatic images for RTP. Therefore, we assessed the reproducibility of CT numbers, an important factor on quality assurance, over short and long time periods for different substances at varying energy. CT number difference between measured and theoretical value was investigated. The scanner provided sufficient reproducibility of CT numbers for dose calculation over short and long time periods. The CT numbers of monochromatic images produced by this scanner had reasonable values for dose calculation. The CT to ED conversion curve becomes linear with respect to the relationship between CT numbers and EDs as the energy increases. We conclude that monochromatic imaging from a fast switching system can be applied for the dose calculation, keeping Hounsfield units (HU) stability.

Syntheses of 25-Adamantyl-25-alkyl-2-methylidene-1α,25-dihydroxyvitamin D3 Derivatives with Structure-Function Studies of Antagonistic and Agonistic Active Vitamin D Analogs.

The active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], is a major regulator of calcium homeostasis through activation of the vitamin D receptor (VDR). We have previously synthesized vitamin D derivatives with large adamantane (AD) rings at position 24, 25, or 26 of the side chain to study VDR agonist and/or antagonist properties. One of them-ADTK1, with an AD ring and 23,24-triple bond-shows a high VDR affinity and cell-selective VDR activity. In this study, we synthesized novel vitamin D derivatives (ADKM1-6) with an alkyl group substituted at position 25 of ADTK1 to develop more cell-selective VDR ligands. ADKM2, ADKM4, and ADKM6 had VDR transcriptional activity comparable to 1,25(OH)2D3 and ADTK1, although their VDR affinities were weaker. Interestingly, ADKM2 has selective VDR activity in kidney- and skin-derived cells-a unique phenotype that differs from ADTK1. Furthermore, ADKM2, ADKM4, and ADKM6 induced osteoblast differentiation in human dedifferentiated fat cells more effectively than ADTK1. The development of vitamin D derivatives with bulky modifications such as AD at position 24, 25, or 26 of the side chain is useful for increased stability and tissue selectivity in VDR-targeting therapy.

Complete genome sequence of Sphingobium sp. strain SYK-6, a degrader of lignin-derived biaryls and monoaryls.

Sphingobium sp. strain SYK-6 is able to grow on an extensive variety of lignin-derived biaryls and monoaryls, and the catabolic genes for these compounds are useful for the production of industrially valuable metabolites from lignin. Here we report the complete nucleotide sequence of the SYK-6 genome which consists of the 4,199,332-bp-long chromosome and the 148,801-bp-long plasmid.

Differential expression and function of alternative splicing variants of human liver X receptor α.

The liver X receptor α (LXRα) is a nuclear receptor that is involved in regulation of lipid metabolism, cellular proliferation and apoptosis, and immunity. In this report, we characterize three human LXRα isoforms with variation in the ligand-binding domain (LBD). While examining the expression of LXRα3, which lacks 60 amino acids within the LBD, we identified two novel transcripts that encode LXRα-LBD variants (LXRα4 and LXRα5). LXRα4 has an insertion of 64 amino acids in helix 4/5, and LXRα5 lacks the C-terminal helices 7 to 12 due to a termination codon in an additional exon that encodes an intron in the LXRα1 mRNA. LXRα3, LXRα4, and LXRα5 were expressed at lower levels compared with LXRα1 in many human tissues and cell lines. We also observed weak expression of LXRα3 and LXRα4 in several tissues of mice. LXR ligand treatment induced differential regulation of LXRα isoform mRNA expression in a cell type-dependent manner. Whereas LXRα3 had no effect, LXRα4 has weak transactivation, retinoid X receptor (RXR) heterodimerization, and coactivator recruitment activities. LXRα5 interacted with a corepressor in a ligand-independent manner and inhibited LXRα1 transactivation and target gene expression when overexpressed. Combination of LXRα5 cotransfection and LXRα antagonist treatment produced additive effects on the inhibition of ligand-dependent LXRα1 activation. We constructed structural models of the LXRα4-LBD and its complexes with ligand, RXR-LBD, and coactivator peptide. The models showed that the insertion in the LBD can be predicted to disrupt RXR heterodimerization. Regulation of LXRα pre-mRNA splicing may be involved in the pathogenesis of LXRα-related diseases.

Whole genome sequence of Desulfovibrio magneticus strain RS-1 revealed common gene clusters in magnetotactic bacteria.

Magnetotactic bacteria are ubiquitous microorganisms that synthesize intracellular magnetite particles (magnetosomes) by accumulating Fe ions from aquatic environments. Recent molecular studies, including comprehensive proteomic, transcriptomic, and genomic analyses, have considerably improved our hypotheses of the magnetosome-formation mechanism. However, most of these studies have been conducted using pure-cultured bacterial strains of alpha-proteobacteria. Here, we report the whole-genome sequence of Desulfovibrio magneticus strain RS-1, the only isolate of magnetotactic microorganisms classified under delta-proteobacteria. Comparative genomics of the RS-1 and four alpha-proteobacterial strains revealed the presence of three separate gene regions (nuo and mamAB-like gene clusters, and gene region of a cryptic plasmid) conserved in all magnetotactic bacteria. The nuo gene cluster, encoding NADH dehydrogenase (complex I), was also common to the genomes of three iron-reducing bacteria exhibiting uncontrolled extracellular and/or intracellular magnetite synthesis. A cryptic plasmid, pDMC1, encodes three homologous genes that exhibit high similarities with those of other magnetotactic bacterial strains. In addition, the mamAB-like gene cluster, encoding the key components for magnetosome formation such as iron transport and magnetosome alignment, was conserved only in the genomes of magnetotactic bacteria as a similar genomic island-like structure. Our findings suggest the presence of core genetic components for magnetosome biosynthesis; these genes may have been acquired into the magnetotactic bacterial genomes by multiple gene-transfer events during proteobacterial evolution.

Vitamin D receptor activation enhances benzo[a]pyrene metabolism via CYP1A1 expression in macrophages.

Benzo[a]pyrene (BaP) activates the aryl hydrocarbon (AHR) and induces the expression of genes involved in xenobiotic metabolism, including CYP1A1. CYP1A1 is involved not only in BaP detoxification but also in metabolic activation, which results in DNA adduct formation. Vitamin D receptor (VDR) belongs to the NR1I subfamily of the nuclear receptor superfamily, which also regulates expression of xenobiotic metabolism genes. We investigated the cross-talk between AHR and VDR signaling pathways and found that 1α,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], a potent physiological VDR agonist, enhanced BaP-induced transcription of CYP1A1 in human monocytic U937 cells and THP-1 cells, breast cancer cells, and kidney epithelium-derived cells. 1,25(OH)(2)D(3) alone did not induce CYP1A1, and 1,25(OH)(2)D(3) plus BaP did not increase CYP1A2 or CYP1B1 mRNA expression in U937 cells. The combination of 1,25(OH)(2)D(3) and BaP increased CYP1A1 protein levels, BaP hydroxylation activity, and BaP-DNA adduct formation in U937 cells and THP-1 cells more effectively than BaP alone. The combined effect of 1,25(OH)(2)D(3) and BaP on CYP1A1 mRNA expression in U937 cells and/or THP-1 cells was inhibited by VDR knockdown, VDR antagonists, and α-naphthoflavone, an AHR antagonist. Electrophoretic mobility shift assays and chromatin immunoprecipitation assays showed that VDR directly bound to an everted repeat (ER) 8 motif in the human CYP1A1 promoter. Thus, CYP1A1 is a novel VDR target gene involved in xenobiotic metabolism. Induction of CYP1A1 by the activation of VDR and AHR may contribute to BaP-mediated toxicity and the physiological function of this enzyme.

Trans-membrane peptide therapy for malignant glioma by use of a peptide derived from the MDM2 binding site of p53.

A new strategy is required against glioblastoma, a highly aggressive and fatal disease. In recent studies the protein transduction domains (PTDs) of some proteins, which are able to cross biological membranes, have been identified as critical domains for protein transduction. Here, we show that this protein-delivery system is a powerful tool for transduction of p53, a biologically active tumor-suppressor protein, into cancer cells, to suppress their proliferation. A 15-amino-acid sequence corresponding to the mouse double minutes clone2 (MDM2) binding site of p53 was shown by cell proliferation assay and MTT assay to have a proliferation-inhibiting effect on glioma cells. The polyarginine11R as a PTD, nuclear localization sequence (NLS), and laminin (Ln) fused to the p53 peptide corresponding to the MDM2 binding site (p53-NLS-Ln-11R) effectively penetrated the plasma membrane of the glioma cells and was translocated into the nucleus. At a 10 µM: concentration, this peptide inhibited the proliferation of human glioma cells, whether the p53 gene had mutated or not. These results suggest that this protein-transduction method using the p53-NSL-Ln-11R peptide may become a promising glioma therapy as an alternative gene therapy.

Capillary ion electrophoresis-capacitively coupled contactless conductivity detection of inorganic cations in human saliva on a polyvinyl alcohol-coated capillary.

Capillary ion electrophoresis-capacitively coupled contactless conductivity detection (CIE-C4D) with a polyvinyl alcohol chemically coated capillary (PVA capillary) was used to analyze inorganic cations (Na(+), K(+), NH(4)(+), Mg(2+), and Ca(2+)) commonly found in human saliva. The PVA capillary, which was made by our laboratory, minimized electro-osmotic flow in the wide pH range of the background electrolyte (BGE), and the PVA layer adsorbed to capillary wall did not affect the conductimetric background level. In this study, we determined an optimized BGE of 30 mM lactic acid/histidine plus 3 mM 18-crown-6 for the CIE-C4D system using the PVA capillary, which could simultaneously improve the separation of Mg(2+) and Ca(2+) from Na(+) and that of K(+) from NH(4)(+). This system obtained highly reproducible separation of cations in human saliva samples within 8 min at 20 kV without deprotonation. The quantifiability of cations in human saliva samples on the CIE-C4D system was demonstrated through identification by ion chromatography with satisfactory results.

Hairless modulates ligand-dependent activation of the vitamin D receptor-retinoid X receptor heterodimer.

The active form of vitamin D, 1α,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], binds to the vitamin D receptor (VDR) and regulates various physiological and pharmacological processes. Secondary bile acids, such as lithocholic acid (LCA), also act as endogenous VDR ligands. The molecular basis of ligand-selective VDR action remains largely unknown. Hairless (HR) acts as a coregulator of VDR through a direct interaction. HR mutations confer an alopecia phenotype similar to VDR mutations in mice and humans, but the underlying molecular mechanisms have not been elucidated. We examined the effect of HR on VDR activation induced by 1,25(OH)(2)D(3) and LCA. HR repressed VDR transactivation induced by both 1,25(OH)(2)D(3) and LCA. HR also repressed transactivation of VDR E269A and R391A mutants, but less effectively than that of wild-type VDR. These residues are involved in retinoid X receptor (RXR) heterodimer allosteric communication, through which information from ligands is transmitted to dimer and coactivator interfaces. In the presence of HR cotransfection, LCA activated these VDR mutants more effectively than wild-type VDR. In mammalian two-hybrid assays, HR enhanced the association of VDR with a corepressor, nuclear receptor corepressor. These findings indicate that HR affects VDR-RXR heterodimer allosteric communication and corepressor complex formation. Interestingly, HR knockdown in keratinocyte-derived HaCaT cells increased ligand-induced cytochrome P450, family 24, subfamily A, polypeptide 1 (CYP24A1) expression but suppressed expression of cathelicidin antimicrobial peptide, indicating that HR acts not only as a corepressor but also as a coactivator. HR may be a VDR modulator that affects the RXR allosteric communication network in order to regulate transcription in a gene-selective manner.

[The potential of dual-energy virtual monochromatic imaging in reducing renal cyst pseudoenhancement: a phantom study].

Renal cyst pseudoenhancement, an artifactual increase of computed tomography (CT) attenuation for cysts with increased iodine concentrations in the renal parenchyma, complicates the classification of cysts and may thus lead to the mischaracterization of a benign non-enhancing lesion as an enhancing mass. The purpose of this study was to use a phantom model to assess the ability of dual-energy virtual monochromatic imaging to reduce renal pseudoenhancement. A water-filled cylindrical cyst model suspended in varying concentrations of iodine solution, to simulate varying levels of parenchymal enhancement, was scanned with a dual-energy CT scanner using the following three scanning protocols with different combinations of tube voltage: 80 and 140 kV; 80 and 140 kV with tin filter; and 100 and 140 kV with tin filter. Virtual monochromatic images were then synthesized for each dual-energy scan. Single-energy scan with a tube voltage of 120 kV was also performed to obtain polychromatic images as controls. Mean attenuation values (in Hounsfield units) of cyst proxies were measured on both polychromatic and virtual monochromatic images. Pseudoenhancement was considered to be present when the cyst attenuation level increased by more than 10 HU as the background iodine concentration increased from 0.0% to 0.4%, 1.5%, or 2.5%. Our results revealed that pseudoenhancement was not observed on any of the monochromatic images, but appeared on polychromatic images at a background iodine concentration of 2.5%. We thus conclude that dual-energy virtual monochromatic images have a potential to reduce renal pseudoenhancement.

Dynamic and ligand-selective interactions of vitamin D receptor with retinoid X receptor and cofactors in living cells.

The vitamin D receptor (VDR) mediates vitamin D signaling in numerous physiological and pharmacological processes, including bone and calcium metabolism, cellular growth and differentiation, immunity, and cardiovascular function. Although transcriptional regulation by VDR has been investigated intensively, an understanding of ligand-selective dynamic VDR conformations remains elusive. Here, we examined ligand-dependent dynamic interactions of VDR with retinoid X receptor (RXR), steroid receptor coactivator 1 (SRC-1), and silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) in cells using fluorescence resonance energy transfer (FRET) and chromatin immunoprecipitation (ChIP) assays. We compared the effects of 1α,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], lithocholic acid (LCA), and (25R)-25-adamantyl-1α,25-dihydroxy-2-methylene-22,23-didehydro-19,26,27-trinor-20-epivitamin D(3) (ADTT), a partial agonist/antagonist vitamin D derivative. In the absence of ligand, VDR homodimers were preferred to RXR heterodimers and were associated with SMRT. 1,25(OH)(2)D(3) induced heterodimerization with RXR, dissociation of SMRT, and association of SRC-1. LCA and ADTT induced those effects to a lesser extent at concentrations that did not induce expression of the VDR target gene CYP24A1 in human embryonic kidney (HEK) 293 cells. Unlike in HEK293 cells, ADTT increased CYP24A1 expression in HCT116 cells and increased the association of VDR and SMRT on the CYP24A1 promoter. The results indicate that ligand-selective conformation may lead to unique cofactor complex formation in a cell context-dependent manner. The combination of FRET and ChIP assays is a powerful tool useful in understanding ligand-selective dynamic VDR conformations and the development of selective VDR modulators.

Breast diffusion-weighted MRI: comparison of tetrahedral versus orthogonal diffusion sensitization for detection and localization of mass lesions.

PURPOSE: To evaluate the potential of tetrahedral diffusion-weighted imaging (DWI) compared to orthogonal DWI for detection and localization of early enhanced breast mass lesions at 1.5T. MATERIALS AND METHODS: Sixty-seven consecutive patients (mean age 51.7 years, range 14-84 years) with 68 solitary early enhanced breast lesions suspicious for cancer on dynamic contrast-enhanced magnetic resonance imaging (MRI) were enrolled in this retrospective study. Two radiologists independently observed maximum intensity projection images of orthogonal and tetrahedral DWI and the diagnostic accuracy and background tissue visibility between two DWI techniques were compared. Contrast-enhanced MRI was used as the reference standard. Background tissue visibility was assessed based on whether the "breast quadrant" and "skin line" were determined. A phantom validation study for apparent diffusion coefficient (ADC) values was also conducted. RESULTS: Sensitivity (93%) and specificity (96%) on tetrahedral DWI were equivalent to those on orthogonal DWI (sensitivity, 88%; specificity, 95%). Background tissue was more easily determined with tetrahedral DWI (breast quadrant, 90%; skin lines, 95%) than with orthogonal DWI (breast quadrant, 61%; skin lines, 16%). ADC values of tetrahedral DWI were highly correlated with those of orthogonal DWI. CONCLUSION: Tetrahedral DWI provided equivalent detectability of mass lesions with improved visibility of surrounding anatomical structure.

A comparison of sarcopenia prevalence between former Tokyo 1964 Olympic athletes and general community-dwelling older adults.

BACKGROUND: This study aimed to determine how increased muscle mass and athletic performance in adolescence contribute to the prevention of sarcopenia in old age, accounting for the type of sport and the continuation of exercise habits. We compared the prevalence of sarcopenia, its components (low appendicular skeletal muscle mass, low muscle strength, and low physical function), and musculoskeletal pain using data from two cohorts: former athletes who competed in the 1964 Tokyo Olympics and general community-dwelling older adults living in Kashiwa City, Chiba Prefecture. METHODS: We analysed the data from 101 former Olympic athletes (mean age ± SD: 75.0 ± 4.4 years; 26% female) and 1529 general community-dwelling older adults (74.1 ± 5.5 years; 49% women). We assessed sarcopenia (defined by the Asian Working Group for Sarcopenia revised in 2019) and musculoskeletal pain and considered potential confounding factors such as demographic characteristics, for example, sex and exercise habits. RESULTS: The prevalence of sarcopenia was significantly lower in former Olympic athletes than general older adults (odds ratios [OR], 0.49; 95% confidence interval [CI], 0.20-0.94), especially with regard to superior appendicular skeletal muscle mass and muscle strength. This effect was more pronounced in individuals who continued their exercise and in athletes whose sporting discipline was classified as having a high exercise intensity. Conversely, low physical function (OR, 2.60; 95% CI, 1.16-6.07) and musculoskeletal pain (OR, 2.22; 95% CI, 1.24-3.97) were more prevalent in former Olympic athletes and in athletes who competed in sports with physical contact. CONCLUSIONS: We observed a lower prevalence of sarcopenia and superior appendicular skeletal muscle mass and strength in the former Olympic athletes, especially among those that continued their exercise habits and those in sports with high exercise intensity. Conversely, low physical function and higher musculoskeletal pain scores were more prevalent in former Olympic athletes, especially among athletes who competed in sports with physical contact. Our results warrant further promotion of exercise in adolescence and beyond as well as providing safety education, which is required to prevent the development of sarcopenia and musculoskeletal pain in old age.

Mortality of Japanese Olympic athletes in 1964 Tokyo Olympic Games.

OBJECTIVES: To compare the mortality of Japanese athletes in the 1964 Tokyo Olympic Games with that of the Japanese population, and to elucidate factors associated with their mortality. METHODS: We obtained from the Japan Sport Association study subjects' biographical information, information on lifestyles and medical data. Missing data were obtained from online databases. Standardised mortality ratio (SMR) was calculated to compare athletes' mortality with the Japanese population. Cox proportional hazards model was applied to estimate the HR for each category of body mass index (BMI), smoking history and handgrip strength. This analysis was limited to male athletes due to the small number of female athletes. RESULTS: Among 342 (283 men, 59 women) athletes, deaths were confirmed for 70 (64 men, 6 women) athletes between September 1964 and December 2017. Total person years was 15 974.8, and the SMR was 0.64 (95% CI 0.50 to 0.81). Multivariate analysis performed on 181 male athletes. Mortality was significantly higher for BMI≥25 kg/m2 than for 21-23 kg/m2 (HR: 3.03, 95% CI 1.01 to 9.07). We found no statistically significant associations between smoking history and mortality; the HR (95% CI) for occasional and daily smokers were 0.82 (0.26 to 2.57) and 1.30 (0.55 to 3.03) compared with never smokers. We also found no statistically significant associations between handgrip strength and mortality (P for trend: 0.51). CONCLUSION: Japanese athletes in the 1964 Tokyo Olympic Games lived longer than the Japanese population. BMI≥25 kg/m2 was associated with higher mortality, but smoking history and handgrip strength were not associated with mortality.

Flexible ligand recognition of peroxisome proliferator-activated receptor-gamma (PPARgamma).

The peroxisome proliferator-activated receptor-gamma (PPARgamma) is a direct pharmacological target for drugs that enhance insulin sensitivity and are used clinically for the treatment of type II diabetes. Because the specificity of ligand recognition is lower for PPARgamma than for other nuclear receptors, PPARgamma can bind a larger variety of ligand types. In order to elucidate why the ligand recognition of PPARgamma is so flexible, we performed correlated fragment molecular orbital calculations for complexes of PPARgamma and each of two distinctive ligands, rosiglitazone and farglitazar. We found quite different patterns of ligand binding for these two ligands. The ligand-binding system of rosiglitazone, a drug in common clinical use, is based mainly on local electrostatic interactions around the thiazolidine ring, whereas both electrostatic interactions and van der Waals dispersion interactions with hydrophobic residues are required for the binding of farglitazar to PPARgamma. We suggest that the development of novel ligands will require adequately hydrophobic pharmacophores.

[Possible mechanism for regulation of inflammatory responses with the S100A8/A9 protein].

We have described a possible mechanism for the regulation of excessive inflammatory responses with S100A8/A9 protein in damaged rat livers. Recombinant human S100A8(r-S100A8) and S100A9 (r-S100A9) were expressed in E. coli cells, and their heterodimer (r-S100A8/A9) with 90% approximate purity was also prepared successfully. The effect of the r-S100A8/A9 on suppression of acute inflammatory changes in rat livers with LPS-induced damage was microscopically observed. Indeed, the liver damage diminished as the dose of the r-S100A8/A9 increased, and the minimum requirement of the protein was estimated to be 1,000 microg/rat in this study. Observation of superoxide anions was positively observed in control rats treated with LPS alone, but almost not in the livers of rats treated with the r-S 100A8/A9 1h after injection of LPS. This fact strongly suggests that the r-S100A8/A9 could indirectly suppress production of such internal oxidants according to unknown pathway (s) in acute inflammation. Expression of mRNAs of several kinds of inflammatory cytokines, such as TNF-alpha, IL-6 and IL-1beta, was also significantly suppressed, which was of much note. Therefore, the possibility that the r-S100A8/A9 partly inhibits the process of signal transduction of inflammatory responses in the immunological cells leading to down regulation of inflammatory changes in vivo was suggested in this study. Conclusively, S100A8/A9 is not necessarily an inflammatory-induced factor, and preferably effective on suppression of excessive inflammatory reaction in vivo dose-dependently, although the mechanism is still unclear.