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In children and younger adults up to 39 years of age, SARS-CoV-2 usually elicits mild symptoms that resemble the common cold. Disease severity increases with age starting at 30 and reaches astounding mortality rates that are ~330 fold higher in persons above 85 years of age compared to those 18-39 years old.To understand age-specific immune pathobiology of COVID-19 we have analyzed soluble mediators, cellular phenotypes, and transcriptome from over 80 COVID-19 patients of varying ages and disease severity, carefully controlling for age as a variable. We found that reticulocyte numbers and peripheral blood transcriptional signatures robustly correlated with disease severity. By contrast, decreased numbers and proportion of naïve T-cells, reported previously as a COVID-19 severity risk factor, were found to be general features of aging and not of COVID-19 severity, as they readily occurred in older participants experiencing only mild or no disease at all. Single-cell transcriptional signatures across age and severity groups showed that severe but not moderate/mild COVID-19 causes cell stress response in different T-cell populations, and some of that stress was unique to old severe participants, suggesting that in severe disease of older adults, these defenders of the organism may be disabled from performing immune protection. These findings shed new light on interactions between age and disease severity in COVID-19.

SUMMARYHIV-positive patients whose viral loads are successfully controlled by active antiretroviral therapy (ART) show no clinical signs of AIDS. However, their lifespan is shorter compared to individuals with no HIV infection and they prematurely exhibit a multitude of chronic diseases typically associated with advanced age. It was hypothesized that immune system aging may correlate with, and provide useful biomarkers for, this premature loss of healthspan in HIV+ subjects. Here, we tested whether the immune correlates of aging, including cell numbers and phenotypes, inflammatory status and control of human cytomegalovirus (hCMV) in HIV-positive subjects on long-term successful ART (HIV+) may reveal increased “immunological age” compared to healthy, age-matched cohort (HC) in participants between 50 and 69 years of age. Specifically, we expected that younger HIV+ subjects may immunologically resemble older individuals without HIV. We found no evidence to support this hypothesis. While T cells from HIV+ participants displayed different expression of several differentiation and/or inhibitory/exhaustion markers in different T cell subpopulations, aging by a decade did not pronounce these changes. Similarly, while the HIV+ participants exhibited higher T cell responses and elevated inflammatory marker levels in plasma, indicative of chronic inflammation, this trait was not age-sensitive. We did find differences in immune control of hCMV, and, more importantly, a sustained elevation of sCD14 and of proinflammatory CD4 and CD8 T cell responses across age groups, pointing towards uncontrolled inflammation as a factor in reduced healthspan in successfully treated older HIV+ patients.

New infections in general, and new viral infections amongst them, represent a serious challenge to an older organism. This review discusses the age-related alterations in responsiveness to infection from the standpoint of virus:host relationship and the host physiological whole-organism and specific immune response to the virus. Changes with age in the innate and adaptive immune system homeostasis and function are reviewed briefly. This is followed by a review of specific alterations and defects in the response of older organisms (chiefly mice and humans) to acute (particularly emerging and re-emerging) viral infections, with a very brief summary of the response to latent persistent infections. Finally, we provide a brief summary of the perspectives for possible interventions to enhance antiviral immunity.

The development of welfare assistive devices for frail elderly people has attracted significant attention for its effort to improve the quality of life and reduce the burden on caregivers. However, it is challenging to conduct multiple user tests because of the significant burden on the elderly; thus, we need efficient ways to extract insight through different approaches. In this study, we aim to elucidate real-time transitions in users’ emotions and achievement motivation while using such a device. We synthesize an utterance analysis method based on attribution theory, in which all users’ utterances are attributed to four categories (ability, effort, task difficulty, and luck) that follow the developed coding rules. Knowing the transitions in causal attribution allows us to extract salient experiences for users, especially by extracting shifts from them and analyzing why the shift occurred and what exactly was happening before and after the shift. If only salient user experiences can be referenced from the aggregate data, useful information can be extracted in a short time to improve system characteristics and the environment. We discussed the validity and reliability of the proposed method by conducting a user test of an electric-assisted four-wheeled cycle for frail elderly people in Kakegawa city in Shizuoka, Japan. We also succeeded in marking the points that need attention, which is about 33% of the total amount of utterance data (1626 utterances), and thus confirmed the potential of the proposed method. Future research should examine how the developed methodology can help designers improve assistive device development, as well as how it can contribute to other fields such as education and social assistance.

Several studies have demonstrated that the SARS-CoV-2 variant-of-concern B.1.1.529 (Omicron) exhibits a high degree of escape from Ab neutralization. Therefore, it is critical to determine how well the second line of adaptive immunity, T cell memory, performs against Omicron. To this purpose, we analyzed a human cohort (n = 327 subjects) of two- or three-dose mRNA vaccine recipients and COVID-19 postinfection subjects. We report that T cell responses against Omicron were largely preserved. IFN-γ–producing T cell responses remained equivalent to the response against the ancestral strain (WA1/2020), with some (∼20%) loss in IL-2 single or IL-2+IFN-γ+ polyfunctional responses. Three-dose vaccinated participants had similar responses to Omicron relative to post–COVID-19 participants and exhibited responses significantly higher than those receiving two mRNA vaccine doses. These results provide further evidence that a three-dose vaccine regimen benefits the induction of optimal functional T cell immune memory.

Emergence of the SARS-CoV-2 variant-of-concern (VOC) B.1.1.529 (Omicron) in late 2021 has raised alarm among scientific and health care communities due to a surprisingly large number of mutations in its spike protein. Public health surveillance indicates that the Omicron variant is significantly more contagious than the previously dominant VOC, B.1.617.2 (Delta). Several early reports demonstrated that Omicron exhibits a higher degree (∼10-30-fold) of escape from antibody neutralization compared to earlier lineage variants. Therefore, it is critical to determine how well the second line of adaptive immunity, T cell memory, performs against Omicron in people following COVID-19 infection and/or vaccination. To that purpose, we analyzed a cohort (n=345 subjects) of two-or three-dose messenger RNA (mRNA) vaccine recipients and COVID-19 post infection subjects (including those receiving 2 doses of mRNA vaccine after infection), recruited to the CDC-sponsored AZ HEROES research study, alongside 32 pre-pandemic control samples. We report that T cell responses against Omicron spike peptides were largely preserved in all cohorts with established immune memory. IFN-γ producing T cell responses remained equivalent to the response against the ancestral strain (WA1/2020), with some (

This study assessed the feasibility of using a vegetable extract, MGM-P (quebracho tannin product), as an alternative to antibiotics for weaned piglets, it investigated MGM-P effects on growth performance, diarrhea, and overall health in early-weaned piglets. In total, 24 piglets were allocated to three treatment groups fed basal diets supplemented with 0, 0.2%, or 0.3% MGM-P for 20 days. The addition of 0.3% MGM-P to the diet of early-weaned piglets improved diarrhea incidence, hematological parameters, and intestinal mucosa structure. Furthermore, the addition of 0.2% or 0.3% MGM-P to the diet of early-weaned piglets did not affect their overall health. Importantly, MGM-P had no effects on average daily gain (ADG), average daily feed intake (ADFI), or feed conversion ratio (FCR). Gut morphology analysis showed that treatment with 0.3% MGM-P enhanced the jejunal villus height (p &lt, 0.05) while reducing the ileal crypt depth (p &lt, 0.05) and colon mucosal thickness (p &lt, 0.05). Collectively, the findings suggested that the use of MGM-P as an alternative to dietary antibiotics could improve diarrhea incidence in early-weaned piglets without negative effects on growth performance or overall health.

Patients with diabetes with coronary microvascular disease (CMD) exhibit higher cardiac mortality than patients without CMD. However, the molecular mechanism by which diabetes promotes CMD is poorly understood. RNA-binding protein human antigen R (HuR) is a key regulator of mRNA stability and translation; therefore, we investigated the role of HuR in the development of CMD in mice with type 2 diabetes. Diabetic mice exhibited decreases in coronary flow velocity reserve (CFVR; a determinant of coronary microvascular function) and capillary density in the left ventricle. HuR levels in cardiac endothelial cells (CECs) were significantly lower in diabetic mice and patients with diabetes than the controls. Endothelial-specific HuR-KO mice also displayed significant reductions in CFVR and capillary density. By examining mRNA levels of 92 genes associated with endothelial function, we found that HuR, Cx40, and Nox4 levels were decreased in CECs from diabetic and HuR-KO mice compared with control mice. Cx40 expression and HuR binding to Cx40 mRNA were downregulated in CECs from diabetic mice. Cx40-KO mice exhibited decreased CFVR and capillary density, whereas endothelium-specific Cx40 overexpression increased capillary density and improved CFVR in diabetic mice. These data suggest that decreased HuR contributes to the development of CMD in diabetes through downregulation of gap junction protein Cx40 in CECs.

Aging is associated with a reduced magnitude of primary immune responses to vaccination and constriction of immune receptor repertoire diversity. Clinical trials demonstrated high efficacy of mRNA based SARS-CoV-2 vaccines in older adults but concerns about virus variant escape have not been well addressed. We have conducted an in-depth analysis of humoral and cellular immunity against an early-pandemic viral isolate and compared that to the P.1. (Gamma) and B.1.617.2 (Delta) variants in 55 age cohorts of mRNA vaccine recipients. We have further measured neutralizing antibody titers for B.1.617.1 (Kappa) and B.1.595; a SARS-CoV-2 isolate bearing Spike mutation E484Q. As reported, robust immunity required the second dose of vaccine. Older vaccinees manifested robust cellular immunity against early-pandemic SARS-CoV-2 and more recent variants, which remained statistically comparable to the adult group. The older cohort had lower neutralizing capacity at the first time point following the second dose, but at later time points immunity was indistinguishable between them. While the duration of these immune responses remains to be determined over longer periods of time, these results provide reasons for optimism regarding vaccine protection of older adults against SARS-CoV-2 variants and inform thinking about boost vaccination with variant vaccines.eTOC summaryVaccine responses are often diminished with aging, but we found strong responses to SARS-CoV-2 in older adults following mRNA vaccination. T cell responses were not diminished when confronted by SARS-CoV-2 variants. Neutralizing Ab were reduced but not more than those in adults.Graphical AbstractCreated with BioRender.com

Aging is associated with a reduced magnitude of primary immune responses to vaccination. mRNA-based SARS-CoV-2 vaccines have shown efficacy in older adults but virus variant escape is still unclear. Here we analyze humoral and cellular immunity against an early-pandemic viral isolate and compare that to the P.1 (Gamma) and B.1.617.2 (Delta) variants in two cohorts (55 age) of mRNA vaccine recipients. We further measure neutralizing antibody titers for B.1.617.1 (Kappa) and B.1.595, with the latter SARS-CoV-2 isolate bearing the spike mutation E484Q. Robust humoral immunity is measured following second vaccination, and older vaccinees manifest cellular immunity comparable to the adult group against early-pandemic SARS-CoV-2 and more recent variants. More specifically, the older cohort has lower neutralizing capacity at 7-14 days following the second dose but equilibrates with the younger cohort after 2-3 months. While long-term vaccination responses remain to be determined, our results implicate vaccine-induced protection in older adults against SARS-CoV-2 variants and inform thinking about boost vaccination.

In order to investigate copper, arsenic, lead and zinc contamination in topsoil of the Erdenet copper mining area in Mongolia, soil samples collected from the surrounding area were examined for trace element concentrations, geochemical fractions, and phase distributions. Fifteen locations (residential area; mine industrial area; control area; tailings dam) were sampled during all four seasons. Of the 19 trace elements determined, the highest concentrations of Cu (1443–4866 mg kg−1), As (26–52 mg kg−1), and Mo (24–49 mg kg−1) in soils from the mine industrial area exceeded the corresponding values listed in the National Standard of Mongolia. Soil samples were fractionated into five phases: exchangeable, carbonate bound, Fe/Mn oxide bound, organic matter bound, and residual. Copper was largely associated with the organic/sulphide fraction, and As, Pb and Zn were associated mainly with the residual and Fe/Mn oxide fractions. Significantly high enrichment factor (EF) and geoaccumulation index (Igeo) values confirmed that Cu and As in the soil from the mine industrial area reach serious levels and their sources may be related to anthropogenic activities such as mining.

Background Diabetic patients with coronary microvascular disease (CMD) exhibit higher cardiac mortality than patients without CMD. However, the molecular mechanism by which diabetes promotes CMD is poorly understood. RNA-binding protein HuR is a key regulator of mRNA stability and translation of many genes, and there is growing evidence showing the potential role of HuR in cardiovascular disease. In this study, we investigated the role of HuR and its target genes in the development of CMD in type 2 diabetic mice. Methods Type 2 diabetes was induced in male mice by a high-fat diet combined with a single injection of low-dose streptozotocin. We assessed coronary flow velocity reserve (CFVR, a determinant of coronary microvascular function) in vivo and isolated cardiac endothelial cells (CECs) from those mice for in vitro experiment. Coronary endothelial function was evaluated in the 3rd order of coronary arteries using a wire myograph. Human CECs from 4 control subjects and 4 diabetic patients were purchased from the company. Results Diabetic mice exhibited decreases in CFVR and capillary density in the left ventricle (LV). HuR protein levels in CECs were significantly lower in diabetic mice and diabetic patients than in the controls. Endothelial-specific HuR-KO mice also displayed significant reductions in CFVR and capillary density. By examining mRNA levels of 92 genes associated with endothelial function, we found that HuR, Cx40, and Nox4 levels were decreased in CECs from diabetic and HuR-KO mice in comparison to control mice. Cx40 protein level and HuR binding to Cx40 mRNA were downregulated in CECs from diabetic mice, and Cx40-KO mice exhibited decreased CFVR, attenuated endothelium-dependent relaxation, and reduced capillary density in the LV. Furthermore, endothelium-specific Cx40 overexpression ameliorated endothelial functions by augmenting endothelium-dependent relaxation and increasing capillary density in the LV, and resulted in the improvement of CFVR in diabetic mice. Conclusions These data suggest that decreased HuR, a specific mRNA binding protein that downregulates gap junction protein Cx40 in CECs, plays an important role in the development of coronary microvascular disease in diabetes. Restoration of Cx40 expression and function is potentially a novel therapeutic strategy for diabetic cardiovascular complications.

Although sclerotia are known as the resting bodies of fungi, the exact biochemical properties of melanized sclerotia that allow them to remain in the soil and retain their structure are unclear. This study aims to examine the mobility and accumulation of metals in melanin-pigmented sclerotia from low pH forest soils, focusing on Al, Cu, Zn, As, and Pb, and to discuss the regulating factors involved in element transfer from soil to sclerotia. Soil and sclerotia samples were collected from five sites, with soil samples analyzed for pH and element composition and sclerotium samples investigated in terms of element composition and

Melanized fungal sclerotia grains were collected from Dark Kastanozem soils in steppe forest, northern Ulaanbaatar, Mongolia (Terelji and Sanzai). Their elemental composition was compared with that of sclerotia grains collected from low-pH soils in three areas in Japan (Rishiri, Komado, Ontake). The elemental compositions of the soil and the sclerotia grains were compared to determine the transfer factors of elements from soil to sclerotia grains. The transfer factors of calcium and copper from Mongolian steppe forest soils were significantly different from those of sclerotia grains from Japanese Andosols. The enrichment of copper in Mongolian sclerotia grains appears to be a result of a biotic mechanism in high-pH conditions.

The micromorphological features of the interiors of sclerotia grains were examined by scanning electron microscopy and transmission electron microscopy combined with energy-dispersive X-ray (SEM-EDX, TEM-EDX) and micro computed tomography (micro-CT) analyses. Spherical particles with a diameter of 100 nm were found inside sclerotia grains and were found to be composed predominantly of carbon and aluminum, suggesting that they are melanin-like particles. Spherical acicular structures, determined to be boehmite by TEM-EDX analysis, were commonly observed by SEM in the center of sclerotia grains. In addition to such aluminum polymorphs, aluminum sulfates and silicon spherical structures, identified as opaline silica, were observed inside sclerotia grains. A graphene-like fraction was observed in the center of sclerotia grains, near titanium oxides or small amounts of adhering calcium, magnesium, or iron oxides. Micro-CT analysis of intact sclerotia grains clearly showed the presence of mycelial strands, that were confined to the interior of the grain.

The relationship between the distribution of fungal sclerotia grains and soil chemical properties was studied in forest soils in the Harz Mountains, Germany. In addition, the micro-topographical distribution of sclerotia grains was examined in a single forest stand. Sclerotia grains were predominantly found in surface horizons (Ah, E horizons) within 10 cm of the soil surface, and the density of grains ranged from 0.01 to 4.99 g kg−1 soil. The content of ergosterol, a biomarker of viable fungal biomass, was correlated with sclerotia grain density in soils. Sclerotia grain density was higher in soils with high ratios (>0.6) of organic bonding aluminum to amorphous aluminum, and with high contents of exchangeable aluminum (Al3+) (>0.54 g kg−1). The content and state of active aluminum appeared to be the factor responsible for the development of sclerotia, because sclerotia grains were not detected in acid soils with a low content of free colloidal aluminum. The intensive clay destruction associated with past lessivage, or clay particle leaching, may have depleted the free colloid aluminum in these forest soils. Although there was no clear relationship between sclerotia distribution and microtopography, field examination of sclerotia grains in soil showed that the presence of sclerotia grains is an indicator of soil chemical properties such as acidity and the degree of soil humification.

Sclerotia grains, fungal resting structures, are commonly found in forest soils, but little is known of their chemical characteristics. Sclerotia samples collected from a buried A horizon from a Japanese Andosol were physically and chemically characterized by scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), Fourier-transform infrared spectrometry, elemental (C-H-N-O) analysis, 13C nuclear magnetic resonance, 27Al nuclear magnetic resonance, particle induced X-ray emission spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. The C, H, N, and O contents of the sclerotia grains were determined to be 47.6, 3.32, 0.78, and 30.2% by mass, respectively. Sclerotia Al, Fe, and Si contents determined by particle induced X-ray emission analysis were 1.4, 0.56, and 0.08%, respectively, in relative agreement with those determined by inductively coupled plasma optical emission spectrometry (1.1, 0.5, and 0.1%, respectively). Functional carbon groups were characterized by dominance of O-alkyl carbon associated with aromatic carbon. Analysis of the 27Al nuclear magnetic resonance spectra showed the presence of 6- and 4-coordinated aluminum. X-ray diffraction analysis showed that the dominant form of aluminum in sclerotia was amorphous. Minor elements such as Ti, Cr, Mn, Cu, Zn, Br, and Pb were detected in the grains at concentrations between 10 and 100 μg g−1.

Sclerotia grains found from soils are not all active for germination but remain in soil. The age of sclerotia grains existing in soils is able to be estimated by 14C dating measurement. Sclerotia grains from surface A horizons and buried A horizons collected from Andosol profiles in central to northern Japan were found to have ages of 100–200 year BP and 300–1200 year BP, respectively. The carbon content of the grains tended to decrease as 14C age increased. The 14C age of sclerotia grains indicates the age of individual grain formation and is more likely to indicate the beginning of soil formation than the 14C age of humic acid. The Al/C atomic ratio of the cell wall and the melanin-like spherules of sclerotia grains were observed using SEM-EDS analysis. Carbon content decreased and aluminum content increased from the outer to the inner portions of the grains, probably owing to microbial degradation. Additionally, the Al/C ratio of sclerotia grains showed a significant positive correlation with 14C age.

Background Abnormal endothelial function in the lungs is implicated in the development of pulmonary hypertension; however, there is little information about the difference of endothelial function between small distal pulmonary artery (PA) and large proximal PA and their contribution to the development of pulmonary hypertension. Herein, we investigate endothelium‐dependent relaxation in different orders of PAs and examine the molecular mechanisms by which chronic hypoxia attenuates endothelium‐dependent pulmonary vasodilation, leading to pulmonary hypertension. Methods and Results Endothelium‐dependent relaxation in large proximal PAs (second order) was primarily caused by releasing NO from the endothelium, whereas endothelium‐dependent hyperpolarization (EDH)–mediated vasodilation was prominent in small distal PAs (fourth–fifth order). Chronic hypoxia abolished EDH‐mediated relaxation in small distal PAs without affecting smooth muscle–dependent relaxation. RNA‐sequencing data revealed that, among genes related to EDH, the levels of Cx37 , Cx40 , Cx43 , and IK were altered in mouse pulmonary endothelial cells isolated from chronically hypoxic mice in comparison to mouse pulmonary endothelial cells from normoxic control mice. The protein levels were significantly lower for connexin 40 (Cx40) and higher for connexin 37 in mouse pulmonary endothelial cells from hypoxic mice than normoxic mice. Cx40 knockout mice exhibited significant attenuation of EDH‐mediated relaxation and marked increase in right ventricular systolic pressure. Interestingly, chronic hypoxia led to a further increase in right ventricular systolic pressure in Cx40 knockout mice without altering EDH‐mediated relaxation. Furthermore, overexpression of Cx40 significantly decreased right ventricular systolic pressure in chronically hypoxic mice. Conclusions These data suggest that chronic hypoxia‐induced downregulation of endothelial Cx40 results in impaired EDH‐mediated relaxation in small distal PAs and contributes to the development of pulmonary hypertension.

Aging is associated with a reduced magnitude of primary immune responses to vaccination and constriction of immune receptor repertoire diversity. Clinical trials demonstrate high efficacy of mRNA based SARS-CoV-2 vaccines in the elderly but concerns about virus variant escape have not been well addressed. Recently, we have conducted an in-depth analysis of humoral and cellular immunity against the early-pandemic virus strain as well as the P.1./Gamma, B.1.617/Delta and B.1.595 SARS-CoV-2 variants in adult and elderly mRNA vaccine recipients. As others have reported, robust immunity required the second dose of vaccine. Older vaccine recipients exhibited an expected 3–5x reduction (but not a complete loss) in neutralizing antibody titers against P.1./Gamma and B.1.595 that did not statistically differ from that measured in adults. Moreover, older vaccinees manifest robust cellular immunity against SARS-CoV-2, including to variants, that remained statistically comparable to the adult group. While the duration of these immune responses remains to be determined over longer periods of time, these results provide reasons for optimism regarding vaccine protection of older adults against SARS-CoV-2 variants. Experiments are currently in progress to determine cellular immunity in adult and older adult mRNA vaccine recipients to Omicron (B.1.1.529), the newest variant of concern. We will present results on T cell polyfunction and production of cytokines in response to Spike protein peptide pool from Omicron variant in a large cohort of convalescents and adult and elderly mRNA vaccine recipients.

We conducted a serological study to define correlates of immunity against SARS-CoV-2. Relative to mild COVID-19 cases, individuals with severe disease exhibited elevated virus-neutralizing titers and antibodies against nucleocapsid (N) and the receptor binding domain (RBD) of spike protein. Age and sex played lesser roles. All cases, including asymptomatic individuals, seroconverted by 2 weeks post-PCR confirmation. Spike RBD and S2 and neutralizing antibodies remained detectable through 5-7 months post-onset, whereas α-N titers diminished. Testing of 5882 members of the local community revealed only 1 sample with seroreactivity to both RBD and S2 that lacked neutralizing antibodies. This fidelity could not be achieved with either RBD or S2 alone. Thus, inclusion of multiple independent assays improved the accuracy of antibody tests in low seroprevalence communities and revealed differences in antibody kinetics depending on the antigen. We conclude that neutralizing antibodies are stably produced for at least 5-7 months after SARS-CoV-2 infection., Graphical Abstract, Highlights • Using independent SARS-CoV-2 antigens improves specificity of serological assays • Neutralizing and spike-specific antibody production persists for at least 5-7 months • Nucleocapsid antibodies frequently become undetectable by 5-7 months • Antibody production is higher in severe disease relative to mild cases, Serological assays for SARS-CoV-2 exposures are challenging due to poor positive predictive values. Ripperger et al. show that combinatorial use of spike receptor binding domain and S2 eliminates almost all false positives. This serological assay is used to show durable antibody production for at least 5-7 months after infection.

We conducted an extensive serological study to quantify population-level exposure and define correlates of immunity against SARS-CoV-2. We found that relative to mild COVID-19 cases, individuals with severe disease exhibited elevated authentic virus-neutralizing titers and antibody levels against nucleocapsid (N) and the receptor binding domain (RBD) and the S2 region of spike protein. Unlike disease severity, age and sex played lesser roles in serological responses. All cases, including asymptomatic individuals, seroconverted by 2 weeks post-PCR confirmation. RBD- and S2-specific and neutralizing antibody titers remained elevated and stable for at least 2-3 months post-onset, whereas those against N were more variable with rapid declines in many samples. Testing of 5882 self-recruited members of the local community demonstrated that 1.24% of individuals showed antibody reactivity to RBD. However, 18% (13/73) of these putative seropositive samples failed to neutralize authentic SARS-CoV-2 virus. Each of the neutralizing, but only 1 of the non-neutralizing samples, also displayed potent reactivity to S2. Thus, inclusion of multiple independent assays markedly improved the accuracy of antibody tests in low seroprevalence communities and revealed differences in antibody kinetics depending on the viral antigen. In contrast to other reports, we conclude that immunity is durable for at least several months after SARS-CoV-2 infection.

Many assistive devices have been developed to assist in the activities of daily life (ADLs) of frail elderly people. However, one of the significant barriers to device development is to conduct multiple user tests due to burdensome to the elderly. Therefore, the potential need for devices must be determined efficiently with some limited opportunities. In this study, we examined whether it is possible to identify target users who can adapt to, and continuously use the device, by utilizing the knowledge of experts who are familiar with the mental and physical conditions of the elderly. As a case study, we analyzed a two-month user test of 57 elderly people with the use of a four-wheel electrically assisted cycle. As a result, the accuracy rate of the expert’s prediction of continuous/discontinuous use over the whole study period was 66.7% before use, but it was improved to 87.7% when the prediction was made again after two rides by elderly people. We also attempted to model this identification rule by multiple regression analysis, and found that experts could predict whether users would use the device long-term by evaluating the following three factors: 1) subjects’ willingness to exercise, 2) their anxiety and dissatisfaction associated with the product, and 3) the ease with which they became fatigued. It is thus proposed that target users can be identified by having a small number of elderly people use the equipment several times, and obtaining expert predictions regarding whether users will continue to use or stop using the device.

BACKGROUND AND PURPOSE: Chloroquine is a traditional medicine to treat malaria. There is increasing evidence that chloroquine not only induces phagocytosis but regulates vascular tone. Few reports investigating the effect of chloroquine on vascular responsiveness of coronary arteries have been made. In this study, we examined how chloroquine affected endothelium‐dependent relaxation in coronary arteries under normal and diabetic conditions. EXPERIMENTAL APPROACH: We isolated coronary arteries from mice and examined endothelium‐dependent relaxation (EDR). Human coronary endothelial cells and mouse coronary endothelial cells isolated from control and diabetic mouse (TALLYHO/Jng [TH] mice, a spontaneous type 2 diabetic mouse model) were used for the molecular biological or cytosolic NO and Ca(2+) measurements. KEY RESULTS: Chloroquine inhibited endothelium‐derived NO‐dependent relaxation but had negligible effect on endothelium‐derived hyperpolarization (EDH)‐dependent relaxation in coronary arteries of control mice. Chloroquine significantly decreased NO production in control human coronary endothelial cells partly by phosphorylating eNOS(Thr495) (an inhibitory phosphorylation site of eNOS) and attenuating the rise of cytosolic Ca(2+) concentration after stimulation. EDR was significantly inhibited in diabetic mice in comparison to control mice. Interestingly, chloroquine enhanced EDR in diabetic coronary arteries by, specifically, increasing EDH‐dependent relaxation due partly to its augmenting effect on gap junction activity in diabetic mouse coronary endothelial cells. CONCLUSIONS AND IMPLICATIONS: These data indicate that chloroquine affects vascular relaxation differently under normal and diabetic conditions. Therefore, the patients' health condition such as coronary macrovascular or microvascular disease, with or without diabetes, must be taken account into the consideration when selecting chloroquine for the treatment of malaria.