A Focused Review of Epstein-Barr Virus Infections and PTLD in Pediatric Transplant Recipients: Guidance From the IPTA and ECIL Guidelines

Epstein-Barr Virus (EBV) diseases, including EBV-associated post-transplant lymphoproliferative disorder (PTLD) remain important causes of morbidity and mortality in children undergoing solid organ transplantation (SOT) and hematopoietic cell transplantation (HCT). Despite progress in the prevention of EBV disease including PTLD (EBV/PTLD) in HCT, key questions in the prevention, and management of these infectious complications remain unanswered. The goal of this manuscript is to highlight key points and recommendations derived from the consensus guidelines published by the International Pediatric Transplant Association and the European Conference on Infections in Leukemia for children undergoing SOT and HCT, respectively. Additionally, we provide background and guidance on the use of EBV viral load measurement in the prevention and management of these children.

Safety and antibody response of the BNT162b2 SARS-CoV-2 vaccine in children aged 5-11 years with underlying diseases: A prospective observational study

BACKGROUND

Data on the safety and antibody response of the BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine in children aged 5-11 years with underlying diseases are limited. Thus, our study aimed to address this gap.

METHODS

This prospective observational study investigated the antibody titers for SARS-CoV-2 spike protein receptor-binding domain (S-IgG) and nucleocapsid protein (N-IgG) in patients aged 5-11 years with chronic underlying diseases following two doses of BNT162b2. Additionally, a questionnaire was used to assess adverse events (AEs) arising within 7 days after each dose. Data on severe AEs arising within 28 days after each dose were extracted from the patients' electronic medical records.

RESULTS

Among 122 patients, 24.6% (30/122) were immunocompromised. Furthermore, 79 patients experienced at least one AE following vaccination, but all recovered without sequelae, including one severe case after the first dose. The seropositivity rate after the second dose was 99.1% (116/117). Excluding 19 N-IgG-positive patients, the geometric mean antibody titer (GMT) was significantly higher in immunocompetent patients than in immunocompromised patients (1496 U/mL [95% confidence interval 1199-1862] vs. 472 U/mL [200-1119], p = 0.035). Additionally, the GMT of S-IgG was higher in N-IgG-positive patients than in N-IgG-negative patients (8203 [5847-11482] U/mL vs. 1127 [855-1486] U/mL, p < 0.001).

CONCLUSIONS

BNT162b2 is acceptably safe and immunogenic for children aged 5-11 years with underlying diseases. Although seroconversion was satisfactory in immunocompromised patients, the titers were lower than in immunocompetent patients.

Association between use of antipyretics and antibody titers after two doses of the BNT162b2 SARS-CoV-2 vaccine in adolescents and young adults with underlying diseases

There are few reports on the association between antipyretic use and antibody titers in adolescents and young adults following SARS-CoV-2 vaccination. Multivariable linear regression analyses were performed to examine the association between antipyretic use and antibody titers. The use of antipyretics was not associated with antibody titers (β coefficient [95% CI] = -0.107 [-0.438 to 0.224]).

Chronic Epstein-Barr viral load carriage after pediatric organ transplantation

Epstein-Barr virus (EBV) infection and EBV-associated post-transplant lymphoproliferative disorder (EBV/PTLD) is one of the most devastating complications occurring in pediatric solid organ transplant (SOT) recipients. Observations of SOT recipients undergoing serial EBV monitoring to inform reduction of immune suppression to prevent EBV-/PTLD has identified patients who maintain chronic high EBV load (CHL) in their blood. The CHL carrier state has been seen more commonly in pediatric compared to adult transplant recipients. Some but not all CHL may progress to EBV/PTLD. However, little is known regarding the biology of this CHL carrier state and the optimal clinical approach to CHL has not been established. This review summarizes the current knowledge and evidence of chronic high EBV load and introduces commonly adopted approaches from experts in this field.

Do attentional focus cues affect the type or number of explicit rules? Proof of concepts of the self-invoking trigger or explicit knowledge hypotheses

Internal focus has been shown to be detrimental to performance by disrupting the motor system, whereas external focus enhances performance by promoting automaticity. One hypothesis, which explains the underlying mechanism of the disruption of the motor system, proposes that internal focus affects the type of thoughts (explicit rules) by invoking self-conscious, evaluative thoughts (McKay et al., 2015). In contrast, another hypothesis proposes that internal focus increases the number of explicit rules, loading working memory (Poolton et al., 2006). To examine the competing hypotheses, neurotypical young adults (22.98 ± 4.46 years old, n = 20 males, n = 40 females) were assigned to one of three groups: external focus (n = 20), internal focus (n = 20), and control (n = 20) groups, and practiced a reciprocal aiming task for two days with retention/transfer tests. Between trials, participant's thoughts were evaluated by an open-ended questionnaire. The type of explicit rules was analyzed using a chi-square test, and the number of explicit rules was analyzed using a mixed-effect Poisson regression. The results showed that external focus resulted in a greater proportion of explicit rules about the task and a lesser proportion of self-evaluative thoughts. The number of explicit rules did not differ between groups. Our results suggest that external focus may strengthen focus on task-relevant features, while internal focus moves people's attention away from important features, potentially explaining why the motor system is disrupted by internal focus.

Elucidating Differences in Early-Stage Centrosome Amplification in Primary and Immortalized Mouse Cells

The centrosome is involved in cytoplasmic microtubule organization during interphase and in mitotic spindle assembly during cell division. Centrosome amplification (abnormal proliferation of centrosome number) has been observed in several types of cancer and in precancerous conditions. Therefore, it is important to elucidate the mechanism of centrosome amplification in order to understand the early stage of carcinogenesis. Primary cells could be used to better understand the early stage of carcinogenesis rather than immortalized cells, which tend to have various genetic and epigenetic changes. Previously, we demonstrated that a poly(ADP-ribose) polymerase (PARP) inhibitor, 3-aminobenzamide (3AB), which is known to be nontoxic and nonmutagenic, could induce centrosome amplification and chromosomal aneuploidy in CHO-K1 cells. In this study, we compared primary mouse embryonic fibroblasts (MEF) and immortalized MEF using 3AB. Although centrosome amplification was induced with 3AB treatment in immortalized MEF, a more potent PARP inhibitor, AG14361, was required for primary MEF. However, after centrosome amplification, neither 3AB in immortalized MEF nor AG14361 in primary MEF caused chromosomal aneuploidy, suggesting that further genetic and/or epigenetic change(s) are required to exhibit aneuploidy. The DNA-damaging agents doxorubicin and γ-irradiation can cause cancer and centrosome amplification in experimental animals. Although doxorubicin and γ-irradiation induced centrosome amplification and led to decreased p27Kip protein levels in immortalized MEF and primary MEF, the phosphorylation ratio of nucleophosmin (Thr199) increased in immortalized MEF, whereas it decreased in primary MEF. These results suggest that there exists a yet unidentified pathway, different from the nucleophosmin phosphorylation pathway, which can cause centrosome amplification in primary MEF.

No Additional Risk of Ampicillin Rash Among Pediatric Liver Transplant Recipients With Concurrent Epstein-Barr Virus Infection

BACKGROUND

Epstein-Barr virus (EBV) infection frequently develops in children undergoing liver transplantation (LT) because of mandated immunosuppressive therapy. There is a risk of ampicillin rash when penicillin derivatives are used in patients with EBV-associated infectious mononucleosis. Hence, the administration of penicillin derivatives may raise concerns about ampicillin rash in patients with high EBV loads. However, no studies confirmed the risk of administering penicillin derivatives to EBV-infected children after LT.

METHODS

This retrospective study was conducted at the largest pediatric transplantation center in Japan. We investigated all pediatric liver transplant recipients who received penicillin derivatives within 2 years of LT between 2014 and 2020. We separated the cohort into EBV-positive and EBV-negative groups to assess the frequency of ampicillin and antibiotic-associated rash.

RESULTS

Two hundred eighty-six liver transplant recipients were enrolled. There were 111 recipients in the EBV-positive group and 175 recipients in the EBV-negative group. In the EBV-positive group, 49 patients had high EBV DNA loads (≥1000 copies/µg DNA). None of the patients in either group developed ampicillin rash, and the frequency of antibiotic-associated rash did not differ [8/111 (7.2%) vs. 10/175 (5.7%), P = 0.797]. Additional subgroup analysis revealed no difference in the frequency of antibiotic-associated rashes regardless of the presence or absence of high EBV loads.

CONCLUSIONS

In this study, ampicillin rash was not observed, and antibiotic-associated rash was not associated with concurrent EBV infection. Penicillin derivatives can be used safely, even in liver transplant recipients with persistent asymptomatic EBV infection.

Laboratory Study of Collisionless Magnetic Reconnection

A concise review is given on the past two decades' results from laboratory experiments on collisionless magnetic reconnection in direct relation with space measurements, especially by the Magnetospheric Multiscale (MMS) mission. Highlights include spatial structures of electromagnetic fields in ion and electron diffusion regions as a function of upstream symmetry and guide field strength, energy conversion and partitioning from magnetic field to ions and electrons including particle acceleration, electrostatic and electromagnetic kinetic plasma waves with various wavelengths, and plasmoid-mediated multiscale reconnection. Combined with the progress in theoretical, numerical, and observational studies, the physics foundation of fast reconnection in collisionless plasmas has been largely established, at least within the parameter ranges and spatial scales that were studied. Immediate and long-term future opportunities based on multiscale experiments and space missions supported by exascale computation are discussed, including dissipation by kinetic plasma waves, particle heating and acceleration, and multiscale physics across fluid and kinetic scales.

Updated guidelines for chronic active Epstein-Barr virus disease

Chronic active Epstein-Barr virus disease (CAEBV), formerly named chronic active Epstein-Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein-Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000 IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

Distinct association between chronic Epstein-Barr virus infection and T cell compartments from pediatric heart, kidney, and liver transplant recipients

Chronic Epstein-Barr virus (EBV) infection after pediatric organ transplantation (Tx) accounts for significant morbidity and mortality. The risk of complications, such as posttransplant lymphoproliferative disorders, in high viral load (HVL) carriers is the highest in heart Tx recipients. However, the immunologic signatures of such a risk have been insufficiently defined. Here, we assessed the phenotypic, functional, and transcriptomic profiles of peripheral blood CD8+/CD4+ T cells, including EBV-specific T cells, in 77 pediatric heart, kidney, and liver Tx recipients and established the relationship between memory differentiation and progression toward exhaustion. Unlike kidney and liver HVL carriers, heart HVL carriers displayed distinct CD8+ T cells with (1) up-regulation of interleukin-21R, (2) decreased naive phenotype and altered memory differentiation, (3) accumulation of terminally exhausted (TEX PD-1+T-bet-Eomes+) and decrease of functional precursors of exhausted (TPEX PD-1intT-bet+) effector subsets, and (4) transcriptomic signatures supporting the phenotypic changes. In addition, CD4+ T cells from heart HVL carriers displayed similar changes in naive and memory subsets, elevated Th1 follicular helper cells, and plasma interleukin-21, suggesting an alternative inflammatory mechanism that governs T cell responses in heart Tx recipients. These results may explain the different incidences of EBV complications and may help improve the risk stratification and clinical management of different types of Tx recipients.

New Constraint on Primordial Lepton Flavor Asymmetries

A chiral chemical potential present in the early Universe can source helical hypermagnetic fields through the chiral plasma instability. If these hypermagnetic fields survive until the electroweak phase transition, they source a contribution to the baryon asymmetry of the Universe. In this Letter, we demonstrate that lepton flavor asymmetries above |μ|/T∼9×10^{-3} trigger this mechanism even for vanishing total lepton number. This excludes the possibility of such large lepton flavor asymmetries present at temperatures above 10^{6}  GeV, setting a constraint which is about 2 orders of magnitude stronger than the current CMB and BBN limits.

Early Detection of Epstein-Barr Virus as a Risk Factor for Chronic High Epstein-Barr Viral Load Carriage at a Living-donor-dominant Pediatric Liver Transplantation Center

BACKGROUND

Epstein-Barr virus (EBV) infection and posttransplant lymphoproliferative disorders (PTLDs) after pediatric liver transplantation (LT) account for significant morbidity and mortality. Knowledge of EBV kinetics, epidemiology, and outcomes among pediatric living-donor LT cases is largely lacking. This study aims to provide clinical information related to EBV infection, chronic high EBV load (CHL) carriage, and PTLD at a living-donor-dominant pediatric LT center.

METHODS

A total of 5827 EBV load measurements from 394 LT recipients fulfilling inclusion criteria and their clinical data were analyzed. EBV loads >1000 copies/μg DNA (742 IU/μg DNA) were considered "high," and CHL was defined by persistence >6 mo.

RESULTS

The highlighted results were as follows: (1) 94% of recipients underwent living-donor LT; (2) 80% of EBV seronegative recipients developed first EBV infection <2 y post-LT, and their EBV loads were consistently higher than those of seropositive recipients within <3 y post-LT but did not differ thereafter; (3) 61 (15%) recipients met CHL criteria, but none developed PTLD; (4) age <5 y, cytomegalovirus seronegative donors, and early development of EBV DNAemia <6 mo post-LT were independent risk factors for CHL; (5) the incidence of rejections after 1-y post-LT was comparably low among CHL carriers whose immunosuppression was minimized.

CONCLUSIONS

Early detection of EBV following LT and CMV seronegative donors would facilitate risk stratification to prevent PTLD while titrating immunosuppression among pediatric LT recipients.

Etiology of severe acute hepatitis in a pediatric transplant center in Japan

The proportion of pediatric cases with severe acute hepatitis of unknown etiology in the coronavirus disease 2019 era was higher than that in the pre-coronavirus disease 2019 era in Japan's largest pediatric transplant center. Further research and monitoring are essential.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Successful pediatric liver transplantation case with a positive SARS-CoV-2 test at the time of transplant

AIM

We report a successful liver transplantation (LT) in a child with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.

CASE PRESENTATION

A 3-year-old female patient with decompensated cirrhosis due to Alagille syndrome underwent a split LT with a left lateral segment graft. She had a history of SARS-CoV-2 infection 4 months before LT. She was exposed to SARS-CoV-2 after the decision for organ acceptance. We repeatedly confirmed the negative SARS-CoV-2 test by polymerase chain reaction (PCR) before LT. Liver transplantation was carried out in the negative pressure operational theater with full airborne, droplet, and contact precautions as the patient was considered to be within the incubation period of SARS-CoV-2. The SARS-CoV-2 PCR test became positive in the nasopharyngeal swab specimen at the operation. Remdesivir, the antiviral treatment, was held off due to potential hepatotoxicity and no exacerbation of COVID-19. She received tacrolimus and low-dose steroids per protocol. She remained SARS-CoV-2 positive on postoperative days (PODs) 1, 2, and 5. The presence of antibodies for SARS-CoV-2 at LT was confirmed later. On POD 53, she was discharged without any symptomatic infection.

CONCLUSION

This case demonstrated that a positive SARS-CoV-2 result was not an absolute contraindication for a life-saving LT. Liver transplantation could be safely performed in a pediatric patient with asymptomatic COVID-19 and S-immunoglobulin G antibodies for SARS-CoV-2.

Safety of and antibody response to the BNT162b2 COVID-19 vaccine in adolescents and young adults with underlying disease

BACKGROUND

Data are limited regarding the safety of and antibody response to the BNT162b2 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) messenger ribonucleic acid vaccine in adolescents and young adults with underlying disease.

METHODS

This prospective observational study enrolled patients age 12-25 years with chronic underlying disease who received 2 doses of BNT162b2. A 18-item questionnaire was used to assess adverse events within 7 days post-vaccination, and data regarding severe adverse events were collected from electronic medical records. An antibody titer for the receptor-binding domain of the spike protein in SARS-CoV-2 was used to assess antibody response after the second vaccine dose.

RESULTS

Study participants were 429 patients (241 [56.2%] age 12-15 years; 188 [43.8%] age 16-25 years). The most common underlying diseases were genetic or chromosomal abnormalities and/or congenital anomalies, followed by endocrine or metabolic diseases; 32% of participants were immunocompromised. Severe adverse events were observed after the second dose in 1 (0.4%) patient age 12-15 years and in 2 (1.1%) patients age 16-25 years; all patients recovered. Seropositivity after the second vaccine dose was 99.0%. The geometric mean antibody titer was higher in patients age 12-15 years versus 16-25 years (1603.3 [1321.8-1944.7] U/mL vs. 949.4 [744.2-1211.0] U/mL). Compared with immunocompetent patients, immunocompromised patients had a lower antibody titer (2106.8 [1917.5-2314.7] U/mL vs. 467.9 [324.4-674.8] U/mL).

CONCLUSIONS

Vaccination with BNT162b2 was acceptably safe and immunogenic for adolescents and young adults with underlying disease.

Comparison of clinical characteristics of COVID-19 in pregnant women between the Delta and Omicron variants of concern predominant periods

Background

Information regarding effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant strains on clinical manifestations and outcomes of coronavirus disease 2019 (COVID-19) in pregnant women is limited.

Methods

A retrospective observational study was conducted using the data from the nationwide COVID-19 registry in Japan. We identified pregnant patients with symptomatic COVID-19 hospitalized during the study period. The Delta and Omicron variants of concern (VOC) predominant periods were defined as August 1 to December 31, 2021 and January 1 to May 31, 2022, respectively. Clinical characteristics were compared between the patients in the Delta and Omicron VOC periods. In addition, logistic regression analysis was performed to identify risk factors for developing moderate-to-severe COVID-19.

Results

During the study period, 310 symptomatic COVID-19 cases of pregnant women were identified; 111 and 199 patients were hospitalized during the Delta and Omicron VOC periods, respectively. Runny nose and sore throat were more common, and fatigue, dysgeusia, and olfactory dysfunction were less common manifestations observed in the Omicron VOC period. In the multivariable logistic regression analysis, onset during the later stage of pregnancy (OR: 2.08 [1.24–3.71]) and onset during the Delta VOC period (OR: 2.25 [1.08–4.90]) were independently associated with moderate-to-severe COVID-19, whereas two doses of SARS-CoV-2 vaccine were protective against developing moderate-to-severe COVID-19 (OR: 0.34 [0.13–0.84]).

Conclusions

Clinical manifestations of COVID-19 in pregnant women differed between the Delta and Omicron VOC periods. SARS-CoV-2 vaccination was still effective in preventing severe COVID-19 throughout the Delta and Omicron VOC periods.

Baryon Asymmetry of the Universe from Lepton Flavor Violation

Charged-lepton flavor violation (CLFV) is a smoking-gun signature of physics beyond the standard model. The discovery of CLFV in upcoming experiments would indicate that CLFV processes must have been efficient in the early Universe at relatively low temperatures. In this Letter, we point out that such efficient CLFV interactions open up new ways of creating the baryon asymmetry of the Universe. First, we quote the two-loop corrections from charged-lepton Yukawa interactions to the chemical transport in the standard model plasma, which imply that nonzero lepton flavor asymmetries summing up to B-L=0 are enough to generate the baryon asymmetry. Then, we describe two scenarios of what we call leptoflavorgenesis, where efficient CLFV processes are responsible for the generation of primordial lepton flavor asymmetries that are subsequently converted to a baryon asymmetry by weak sphaleron processes. Here, the conversion factor from lepton flavor asymmetry to baryon asymmetry is suppressed by charged-lepton Yukawa couplings squared, which provides a natural explanation for the smallness of the observed baryon-to-photon ratio.

Successful hematopoietic stem cell transplantation with reduced dose of busulfan for Omenn syndrome

Omenn syndrome (OS) is typically observed in the autosomal recessive form of severe combined immunodeficiency (SCID) with autoreactive manifestations, and it requires allogeneic hematopoietic stem cell transplantation. Unlike non-OS SCID, a conditioning regimen is usually required to eradicate T-cells; however, optimal conditioning regimens are not established mainly because of the rarity of OS. Here, we report a case of hematopoietic stem cell transplantation with a reduced dose of busulfan, as a conditioning regimen and successful engraftment with complete chimerism. OS was diagnosed in a one-month-old boy based on a diffuse erythematous rash, absent B-cells, and activated T-cells. Genetic analysis failed to identify causative mutations for OS/SCID, such as RAG1/2. Bone marrow transplantation was performed from his HLA-matched sister with a conditioning regimen consisting of targeted busulfan, fludarabine, and anti-thymocyte globulin. Cyclosporine had been administered before transplantation to control abnormal T-cell activation and continued for graft-versus-host disease (GVHD) prophylaxis. Engraftment was achieved on day 12, and no GVHD symptoms were observed. For stem cell transplantation for OS, prior control of autoreactive symptoms with immunosuppressants is important for safe transplantation and reduced intensity conditioning (RIC) can be an option to achieve sustained engraftment.

MO942: Regulatory T and B Cell Responses are Equally Compromised During Antibody-Mediated Rejection of Kidney Allografts

BACKGROUND AND AIMS

Although considerable advances have been made in understanding the cellular effector mechanisms responsible for donor-specific antibody (DSA) generation leading to antibody-mediated rejection (ABMR), the identification of cellular regulators of such immune responses is lacking.

METHOD

In a cohort of 96 kidney transplant recipients, we used high-dimensional flow cytometry to concomitantly profile and track the two major subsets of regulatory lymphocytes in the blood: T regulatory (TREG) and transitional B (TrB) cells. Additionally, we established co-culture assays to address their respective capacities to suppress antibody responses in vitro.

RESULTS

TREG and TrB were potent suppressors of T follicular helper-mediated B cell differentiation into plasmablast and antibody generation. While TREG and TrB were both durably expanded in patients who did not develop DSA post-transplant, patients who manifested DSA and progressed to ABMR displayed a marked and persistent numerical reduction in TREG and TrB cells. Strikingly, specific cell clusters expressing the transcription factor T-bet were selectively depleted in both TREG and TrB compartments in patients with ABMR. Importantly, the coordinated loss of these T-bet + CXCR5+ TREG and T-bet+CD21–TrB cell clusters was correlated with increased and inflammatory DSA responses, more extensive microvascular inflammation and a higher rate of kidney allograft loss.

CONCLUSION

Our study identified coordinated and persistent defects in the regulatory T and B cell responses in patients undergoing ABMR, which may contribute to their loss of humoral immune regulation and thus warranting timely therapeutic interventions to replenish and sustain TREG and TrB cells in these patients.

Prevalence of Hoarseness and Its Association with Severity of Dysphagia in Patients with Sarcopenic Dysphagia

OBJECTIVES

To investigate the prevalence of hoarseness and its association with the severity of dysphagia in patients with sarcopenic dysphagia.

DESIGN

Cross-sectional study using the Japanese sarcopenic dysphagia database.

SETTING

19 hospitals including 9 acute care hospitals, 8 rehabilitation hospitals, 2 long-term care hospitals, and 1 home visit rehabilitation team.

PARTICIPANTS

287 patients with sarcopenic dysphagia, aged 20 years and older.

MEASUREMENTS

Sarcopenic dysphagia was diagnosed using a reliable and validated diagnostic algorithm for the condition. The presence and characteristics of hoarseness classified as breathy, rough, asthenic, and strained were assessed. The prevalence of hoarseness and the relationship between hoarseness and Food Intake LEVEL Scale (FILS) were examined. Order logistic regression analysis adjusted for age, sex, naso-gastric tube, and handgrip strength was used to examine the relationship between hoarseness and FILS at baseline and at follow-up.

RESULTS

The mean age was 83 ± 10 years. Seventy-four (26%) patients had hoarseness, while 32 (11%), 20 (7%), 22 (8%), and 0 (0%) patients had breathy, rough, asthenic, and strained hoarseness, respectively. Median FILS at the initial evaluation was 7 (interquartile range, 5-8). Hoarseness (β=0.747, 95% confidence intervals= 0.229, 1.265, p=0.005), age, sex, naso-gastric tube, and handgrip strength were associated independently with baseline FILS, while hoarseness (β=0.213, 95% confidence intervals= -0.324, 0.750, p=0.438) was not associated independently with the FILS at follow-up.

CONCLUSIONS

Hoarseness was associated with the severity of dysphagia at baseline, however not a prognostic factor for sarcopenic dysphagia. Resistance training of swallowing and respiratory muscles and voice training as part of rehabilitation nutrition might be useful for treating sarcopenic dysphagia.

Serum and cerebrospinal fluid acyclovir pharmacokinetics in a neonate with HSV-2 meningoencephalitis

A neonatal patient with Herpes simplex virus type-2 meningoencephalitis was treated by high-dose intravenous acyclovir therapy. Serum and cerebrospinal fluid (CSF) concentrations were measured retrospectively, showing that the CSF-to-serum concentration ratio was 0.67-0.71, which was higher than the previously reported values in other age groups.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

Altered Rheological Properties of Saliva with Aging in Mouse Sublingual Gland

Mucin in saliva plays a critical role in the hydration and lubrication of the oral mucosa by retaining water molecules, and its impaired function may be associated with hyposalivation-independent xerostomia. Age-dependent effects on salivary gland function and rheological properties of secreted saliva are not fully understood as aging is a complex and multifactorial process. We aimed to evaluate age-related changes in the rheological properties of saliva and elucidate the underlying mechanism. We performed ex vivo submandibular gland (SMG) and sublingual gland (SLG) perfusion experiments to collect saliva from isolated glands of young (12 wk old) and aged (27 mo old) female C57BL/6J mice and investigate the rheological properties by determining the spinnbarkeit (viscoelasticity). While fluid secretion was comparable in SMG and SLG of both mice, spinnbarkeit showed a significant decrease in SLG saliva of aged mice than that of young mice. There were no significant differences in GalNAc concentration between young and aged SLG saliva. Liquid chromatography/tandem mass spectrometry analysis of SLG saliva revealed that (Hex)₁ (HexNAc)₁ (NeuAc)₁ at m/z 793.31 was the most abundant O-glycan structure in SLG saliva commonly detected in both mice. Lectin staining of salivary gland tissue showed that SLG stained strongly with Maackia amurensis lectin II (MAL II) while Sambucus nigra agglutinin (SNA) stained little, if any, SLG. The messenger RNA expression of St3gal1 that encodes an α-2,3 sialic acid sialyltransferase SIAT4-A showed a decrease in SLG of aged mice, confirmed by a Western blot analysis. Lectin blot analysis in SLG saliva revealed that the relative signal intensity detected by MAL II was significantly lower in aged SLG. Our results suggest that spinnbarkeit decreases in SLG of aging mice due to downregulation of sialic acid linked to α-2,3 sialic acid sialyltransferase expression.

Mucosal-associated invariant T cells are activated in an interleukin-18-dependent manner in Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases

Mucosal-associated invariant T (MAIT) cells are a type of innate immune cells that protect against some infections. However, the involvement of MAIT cells in Epstein-Barr virus-associated T/natural killer cell lymphoproliferative diseases (EBV-T/NK-LPD) is unclear. In this study, we found that MAIT cells were highly activated in the blood of patients with EBV-T/NK-LPD. MAIT cell activation levels correlated with disease severity and plasma IL-18 levels. Stimulation of healthy peripheral blood mononuclear cells with EBV resulted in activation of MAIT cells, and this activation level was enhanced by exogenous IL-18. MAIT cells stimulated by IL-18 might thus be involved in the immunopathogenesis of EBV-T/NK-LPD.

Clinical characteristics and outcomes of COVID-19 in pregnant women: a propensity score matched analysis of the data from the COVID-19 Registry Japan

Background

Several studies have investigated whether pregnancy is a risk factor for developing severe COVID-19; however, the results remain controversial. In addition, the information regarding risk factors for developing severe COVID-19 in pregnant women is limited.

Methods

A retrospective cohort study analyzing the data from the nationwide COVID-19 registry in Japan was conducted. Propensity score matched analysis was performed to compare COVID-19 severity between pregnant and nonpregnant women. Multivariate analysis was also conducted to evaluate risk factors for developing moderate-to-severe COVID-19 in pregnant women.

Results

During the study period, 254 pregnant and 3752 nonpregnant women of reproductive age were identified. After propensity score matching, 187 pregnant women and 935 nonpregnant women were selected. A composite outcome of moderate-to-severe COVID-19 was more frequently observed in pregnant women than that of nonpregnant women (n=18, 9.6% vs. n=46, 4.9%; P=0.0155). In multivariate analysis, the presence of underlying diseases and being in the second-to-third trimester of pregnancy were recognized as risk factors for moderate-to-severe COVID-19 in pregnant women (odds ratio [95% confidence interval]: 5.295 [1.21-23.069] and 3.871 [1.201-12.477], respectively).

Conclusions

Pregnancy could be a risk factor for moderate-to-severe COVID-19 for women in Japan. In addition to the presence of comorbidities, advanced pregnancy stages may contribute to greater risks for developing moderate-to-severe COVID-19 in pregnant women.

Concomitant loss of regulatory T and B cells is a distinguishing immune feature of antibody-mediated rejection in kidney transplantation

Although considerable advances have been made in understanding the cellular effector mechanisms responsible for donor-specific antibody generation leading to antibody-mediated rejection (ABMR), the identification of cellular regulators of such immune responses is lacking. To clarify this, we used high dimensional flow cytometry to concomitantly profile and track the two major subsets of regulatory lymphocytes in blood: T regulatory (T_REG) and transitional B cells in a cohort of 96 kidney transplant recipients. Additionally, we established co-culture assays to address their respective capacity to suppress antibody responses in vitro. TREG and transitional B cells were found to be potent suppressors of T follicular helper-mediated B-cell differentiation into plasmablast and antibody generation. TREG and transitional B cells were both durably expanded in patients who did not develop donor-specific antibody post-transplant. However, patients who manifested donor-specific antibody and progressed to ABMR displayed a marked and persistent numerical reduction in TREG and transitional B cells. Strikingly, specific cell clusters expressing the transcription factor T-bet were selectively depleted in both TREG and transitional B-cell compartments in patients with ABMR. Importantly, the coordinated loss of these T-bet⁺CXCR5⁺TREG and T-bet⁺CD21^- transitional B-cell clusters was correlated with increased and inflammatory donor specific antibody responses, more extensive microvascular inflammation and a higher rate of kidney allograft loss. Thus, our study identified coordinated and persistent defects in regulatory T- and B-cell responses in patients undergoing ABMR, which may contribute to their loss of humoral immune regulation, and warrant timely therapeutic interventions to replenish and sustain TREG and transitional B cells in these patients.

FTIR study of the surface-ligand exchange reaction with glutathione on biocompatible rod-shaped CdSe/CdS semiconductor nanocrystals

Semiconductor nanocrystals (SNCs) are an essential optical tool in the life sciences. Application of SNCs to living systems requires that their surfaces be covered with biocompatible molecules. The surface capping...

Factors Associated with Increased Caregiver Burden of Informal Caregivers during the COVID-19 Pandemic in Japan

This study's objective was to explore the association between various factors and the increased caregiver burden of informal caregivers during the COVID-19 pandemic. On February, 2021, 700 informal caregivers completed an online survey. We assessed the change in caregiver burden during the COVID-19 pandemic. Among all caregiver participants, 287 (41.0%) complained of an increased caregiver burden due to the COVID-19 pandemic. The factors associated with increased caregiver burden were depressive symptoms in caregivers [odds ratio (OR), 2.20; 95% confidence interval (CI), 1.50-3.23], dementia (OR, 2.48; 95%CI, 1.07-5.73) and low Barthel Index scores (OR, 2.01; 95%CI, 1.39-2.90) in care receivers, care days (OR, 1.09; 95%CI, 1.01-1.17) and times (OR, 1.06; 95%CI, 1.01-1.10), and use of home care service (OR, 1.46; 95%CI, 1.01-2.10) and visiting care service (OR, 1.71; 95%CI, 1.20-2.45). These findings suggest we need to pay attention to the physical and mental health of both the care receivers and caregivers.

Factors associated with prolonged procedure time of embolization for trauma patients

Aim

Limited information exists on the factors associated with prolonged procedural time in embolization for trauma patients. We clarified the clinical application of embolization in trauma patients and factors associated with a prolonged procedure time.

Methods

Medical records of 162 trauma patients who underwent embolization between January 2007 and December 2020 at a regional trauma care center were reviewed retrospectively. Patients were divided into four embolized body regions: chest, abdomen, pelvis, and other. Patient demographics, trauma mechanism, physiology, trauma severity, embolization procedures, and 30‐day mortality were examined. The outcomes were identifying an embolized body region, embolized arteries, and procedure time. Multiple regression model was created to investigate the factors associated with prolonged procedural time in embolization.

Results

Embolization was mainly undertaken in pelvic fractures (n = 96, 59%) and abdominal organ injuries (n = 57, 35%) and extended to the chest (n = 17, 10%), and other (n = 20, 12%). Approximately 13% (n = 21) of patients underwent embolization in two or more regions. Embolization was more strictly performed in minor artery injuries, for example, external iliac (n = 15, 16%) and lumbar artery (n = 22, 23%) branches in pelvic fractures, and inferior phrenic artery (n = 2, 3.5%) branches in liver injuries. Multiple regression model indicated that the number of embolized arteries (P = 0.021) and number of embolized regions (P < 0.001) were associated with prolonged procedural time in embolization.

Conclusions

Embolization for trauma patients extended to various trauma regions. In time‐sensitive embolization, emergency interventional radiologists showed superior knowledge of expected embolizing arteries and factors associated with procedure time.

Association between Inflammation and Functional Outcome in Patients with Sarcopenic Dysphagia

OBJECTIVES

This study aimed to investigate whether inflammation affects the outcome of swallowing ability to improve treatment for sarcopenic dysphagia.

DESIGN

A retrospective observational cohort study was performed using data from the Japanese sarcopenic dysphagia database.

SETTING

The database was constructed using data from 19 hospitals and one home visiting rehabilitation team.

PARTICIPANTS

Patients with sarcopenic dysphagia with measurements of C-reactive protein (CRP) and serum albumin (Alb) were included.

MEASUREMENTS

Patients were assigned to two groups using CRP, Alb, and the Japanese modified Glasgow Prognostic Score (mGPS). The Food Intake LEVEL Scale (FILS) was measured at the times of admission and follow-up (FILS follow-up) to assess swallowing function.

RESULTS

A total of 197 patients were included. Mean or median values of each parameter were as follows: age: 83.8±8.7, Alb: 3.2 ± 0.6 g/dL, CRP: 8.0 [3.0, 29.0] mg/L, mGPS: 1 [1-2], FILS: 7 [6-8], FILS follow-up: 8 [7-8], and duration of follow-up: 57.0 [27.0, 85.0] days. The FILS score at follow-up was significantly lower in the high CRP group (≥ 5.0 mg/L) than in the low CRP group (< 5.0 mg/L) (p = 0.01). Further, the FILS score at follow-up was significantly lower in the high mGPS group (class; 2) than in the low mGPS group (class; 0 and 1) (p = 0.03). In the multiple linear regression analyses without FILS at baseline, CRP and mGPS were independent risk factors for FILS follow-up. When FILS at baseline was entered, CRP and mGPS were not an independent risk factors for FILS follow-up.

CONCLUSIONS

Inflammation could modify the outcome of the patients with sarcopenic dysphagia. Inflammation may be an important risk factor in evaluating patients with sarcopenic dysphagia.

Immunological features and complications in patients with glycogen storage disease 1b after living donor liver transplantation

BACKGROUND

LT is an elective treatment choice for children diagnosed with GSD1b that can improve their quality of life and stabilize their glucose intolerance. However, careful attention should be paid to immunosuppression after LT due to the susceptibility to infection because of neutropenia and neutrophil dysfunction in GSD1b patients. This study revealed the immunological features and complications in the early post-LT period.

METHODS

We compared findings between 11 (1.9%) children with GSD1b and 273 children with BA. Analyses using the PSM were performed to overcome selection bias.

RESULTS

Despite persistent low tacrolimus trough levels in GSD1b patients, none of these children developed TCMR within 1 month after LDLT (GSD1b: 0/11 [0%] vs. BA: 86/273 [31.5%], p = .038). This result was also confirmed in PSM. The incidence of bloodstream infections was higher in GSD1b patients than in BA patients in the early phase of the post-transplant period (GSD1b: 4/11 [36.4%] vs. BA: 33/273 [12.1%], p = .041), but not reach statistical significance in PSM. In a phenotypic analysis, the ratio of CD8⁺ T cells in GSD1b recipients' peripheral blood mononuclear cell samples was lower than in recipients with BA through the first month after LDLT.

CONCLUSIONS

We found that GSD1b recipients were more likely to develop postoperative bloodstream infection than recipients with BA but did not experience TCMR despite low tacrolimus levels in the early post-LDLT period. A tailored immunosuppression protocol should be prepared for GSD1b recipients after LDLT.

A Gastric Metastatic Lesion That Resembled Early-Stage Gastric Cancer on Endoscopy during Treatment for Recurrent Breast Cancer: A Case Report

Breast cancer metastasis to the gastrointestinal tract is relatively rare. Patients with such disease often develop gastrointestinal symptoms, but it is sometimes asymptomatic. Endoscopic findings of gastric metastasis from breast cancer markedly vary from benign to malignant, and even in suspected malignant cases, it is often difficult to differentiate between primary and metastatic disease. We experienced a case in which an endoscopic examination performed during the treatment for metastatic breast cancer resembled an early-stage gastric cancer. A 71-year-old woman underwent curative surgery for right breast cancer 16 years previously. She underwent endoscopic submucosal dissection for early-stage gastric cancer 5 years ago. Two years ago, she developed metastatic disease in the lungs and mediastinal lymph nodes, and endocrine therapy was administered. At the same time, a follow-up endoscopy revealed a new elevated lesion, suspected to be an early-stage gastric cancer. However, histological diagnosis of the biopsy was metastasis of breast cancer. One and a half years later, a follow-up endoscopy revealed a gastric lesion that had reduced in size. She is still alive, having received a variety of systemic treatments. Patients with metastatic breast cancer are experiencing prolonged survival. Thus, follow-up endoscopy should be considered after the diagnosis of gastrointestinal metastasis considering the risk of lethal conditions, such as gastrointestinal bleeding and perforation. Our case serves as a reminder to clinicians how difficult it is to determine whether a gastric lesion is primary or metastatic based on endoscopic findings and the importance of communication with endoscopists and pathologists.

Cosmic Birefringence Triggered by Dark Matter Domination

Cosmic birefringence is predicted if an axionlike particle (ALP) moves after the recombination. We show that this naturally happens if the ALP is coupled to the dark matter density because it then acquires a large effective mass after the matter-radiation equality. Our scenario applies to a broad range of the ALP mass m_{ϕ}≲10^{-28}  eV, even smaller than the present Hubble constant. We give a simple model to realize this scenario, where dark matter is made of hidden monopoles, which give the ALP such a large effective mass through the Witten effect. The mechanism works if the ALP decay constant is of order of the grand unified theory scale without a fine-tuning of the initial misalignment angle. For smaller decay constant, the hidden monopole can be a fraction of dark matter. We also study the implications for the QCD axion, and show that the domain wall problem can be solved by the effective mass.

Hypersensitivity to mosquito bites: A versatile Epstein-Barr virus disease with allergy, inflammation, and malignancy

Hypersensitivity to mosquito bites (HMB) is a rare disease characterized by transient intense skin reaction and systemic inflammation. Clinical presentation of HMB resembles other mosquito allergic responses, and it can also be difficult to clinically distinguish HMB from other severe allergic reactions. However, a distinctive pathophysiology underlies HMB. HMB belongs to a category of Epstein-Barr virus (EBV)-associated natural killer (NK) cell lymphoproliferative disorders (LPD). Hence, HMB may progress to systemic diseases, such as hemophagocytic lymphohistiocytosis, chronic active EBV disease, and EBV-associated malignancies. A triad of elevated serum IgE, NK lymphocytosis, and detection of EBV DNA in peripheral blood is commonly observed, and identification of EBV-infected NK cells usually facilitates the diagnosis. However, the effective treatment is limited, and its precise etiology remains unknown. Local CD4+ T cell proliferation triggered by mosquito bites appears to help induce EBV reactivation and EBV-infected NK-cell proliferation. These immunological interactions may explain the transient HMB signs and symptoms and the disease progression toward malignant LPD. Further research to elucidate the mechanism of HMB is warranted for better diagnosis and treatment of HMB and other forms of EBV-associated LPD.

Diagnostic Accuracy of Diastolic Fractional Flow Reserve for Functional Evaluation of Coronary Stenosis

Background

In the resting conditions, narrowing the window of coronary pressure measurements from the whole cardiac cycle to diastole improves diagnostic performance of coronary pressure–derived physiological index. However, whether this also applies to the hyperemic conditions has not yet been thoroughly evaluated.

Objectives

The purpose of this study was to assess whether diastolic fractional flow reserve (diastolic FFR) has better diagnostic performance in identifying ischemia-causing coronary lesions than conventional FFR in a prospective, multicenter, and independent core laboratory–based environment.

Methods

In this prospective multicenter registry at 29 Japanese centers, we compared the diagnostic performance of FFR, diastolic FFR, resting distal to aortic coronary pressure (Pd/Pa), and diastolic pressure ratio (dPR) using myocardial perfusion scintigraphy (MPS) as the reference standard in 378 patients with single-vessel coronary disease.

Results

Inducible myocardial ischemia was found on MPS in the relevant myocardial territory of the target vessel in 85 patients (22%). In the receiver-operating curve analyses, diastolic FFR had comparable area under the curve (AUC) compared with FFR (AUC_{diastolic FFR}: 0.66; 95% confidence interval [CI]: 0.58-0.73, vs AUC_FFR: 0.66; 95% CI: 0.58-0.74, P = 0.624). FFR and diastolic FFR showed significantly larger AUCs than resting Pd/Pa (0.62; 95% CI: 0.54-0.70; P = 0.033 and P = 0.046) but did not show significantly larger AUCs than dPR (0.62; 95% CI: 0.55-0.70; P = 0.102 and P = 0.113).

Conclusions

Diastolic FFR showed a similar diagnostic performance to FFR as compared with MPS. This result reaffirms the use of FFR as the most accurate invasive physiological lesion assessment. (Diagnostic accuracy of diastolic fractional flow reserve (d-FFR) for functional evaluation of coronary stenosis; UMIN000015906)

A Prospective Viral Monitoring Study After Pediatric Allogeneic Hematopoietic Stem Cell Transplantation for Malignant and Nonmalignant Diseases

Allogeneic hematopoietic stem cell transplantation (HSCT) is the treatment of choice for many high-risk pediatric hematological malignant diseases (MD) and several nonmalignant diseases (NMD), including primary immune deficiencies. Infections must be managed to obtain better outcomes after HSCT. In this prospective observational study, viral monitoring was performed on 74 pediatric patients with MD and NMD who underwent HSCT. The incidence, risk factors, and impact of common opportunistic viral infections occurring within the first 100 days following HSCT were assessed. The viral pathogens included human herpesviruses, BK polyomavirus (BKV), adenovirus, parvovirus B19, and hepatitis B virus. In total, 52 (70%) patients had viral DNAemia, and 53% and 41% of patients developed human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) DNAemia, respectively. The risk factors were as follows: negative CMV serology for any viral infections; age ≥ 2 years and negative CMV serology for HHV-6; age ≥5 years and female sex for BKV. The risk of viral infection did not significantly differ between MD and NMD, and no risk factor was identified for viral disease, likely because of the small sample numbers. However, despite the absence of symptoms, CMV DNAemia was found to increase the risk of mortality. The findings of the current study could improve the risk stratification and the management of pediatric HSCT recipients.

TRENDS IN THE PREVALENCE OF FRAILTY IN JAPAN: A META-ANALYSIS FROM THE ILSA-J

OBJECTIVE

To examine whether age-specific prevalence of frailty in Japan changed between 2012 and 2017.

DESIGN

This study performed meta-analyses of data collected from 2012 to 2017 using the Integrated Longitudinal Studies on Aging in Japan (ILSA-J), a collection of representative Japanese cohort studies.

SETTING

The ILSA-J studies were conducted on community-living older adults.

PARTICIPANTS

ILSA-J studies were considered eligible for analysis if they assessed physical frailty status and presence of frailty in the sample. Seven studies were analyzed for 2012 (±1 year; n = 10312) and eight studies were analyzed for 2017 (±1 year; n = 7010). Five studies were analyzed for both 2012 and 2017.

MEASUREMENTS

The study assessed the prevalence of frailty and frailty status according to 5 criteria: slowness, weakness, low activity, exhaustion, and weight loss.

RESULTS

The overall prevalence of physical frailty was 7.0% in 2012 and 5.3% in 2017. The prevalence of frailty, especially in people 70 years and older, tended to decrease in 2017 compared to 2012. Slight decreases were found in the prevalence of frailty subitems including weight loss, slowness, exhaustion, and low activity between 2012 and 2017, but change in the prevalence of weakness was weaker than other components.

CONCLUSIONS

The prevalence of physical frailty decreased from 2012 to 2017. There are age- and gender-related variations in the decrease of each component of frailty.

Wash-In Leptogenesis

We present a leptogenesis mechanism based on the standard type-I seesaw model that successfully operates at right-handed-neutrino masses as low as a few hundred TeV. This mechanism, which we dub wash-in leptogenesis, does not require any CP violation in the neutrino sector and can be implemented even in the regime of strong wash-out. The key idea behind wash-in leptogenesis is to generalize standard freeze-out leptogenesis to a nonminimal cosmological background in which the chemical potentials of all particles not in chemical equilibrium at the temperature of leptogenesis are allowed to take arbitrary values. This sets the stage for building a plethora of new baryogenesis models where chemical potentials generated at high temperatures are reprocessed to generate a nonvanishing B-L asymmetry at low temperatures. As concrete examples, we discuss wash-in leptogenesis after axion inflation and in the context of grand unification.

Fatal Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis with virus-infected T cells after pediatric multivisceral transplantation: A proof-of-concept case report

BACKGROUND

EBV-associated HLH driven by EBV-infected CD8⁺ T cells is a rare complication after pediatric solid organ transplantation. The etiology and disease spectrum of post-transplant EBV-HLH are poorly understood, and making a precise diagnosis and providing optimal treatment remain a challenge.

METHODS/CASE DESCRIPTION/RESULTS

We report a 2-year-old multivisceral transplant recipient who developed fever and cytopenia with a persistent high EBV-load state. Repeated tissue examinations and CT scans could not identify a localized mass, which is the key to the diagnosis of PTLD as per the WHO classification. Hence, EBV-HLH was diagnosed by clinical manifestations as well as characterization of EBV-infected cells, pathological examination on cell block of pleural effusion and clonality analysis. This EBV-HLH did not respond to intensive chemotherapy, resulted in the recipient's death, acting similarly to hematological malignancy.

CONCLUSIONS

Characterization of EBV-infected cells in peripheral blood should be considered when persistent high EBV loads develop with symptoms consistent with PTLD, but no evidence of localized mass, and the tissue diagnosis is unavailable after pediatric solid organ transplantation.

An acidic morpholine derivative containing glyceride from thraustochytrid, Aurantiochytrium

A novel acidic morpholine-derivative containing glyceride (M-glyceride) was isolated from the cells of two strains of the thraustochytrid, Aurantiochytrium. The glyceride accounted for approximately 0.1 -0.4% of the lyophilized cells. The glyceride consisted of peaks I (85%) and II (15%). The structures of the intact and acetylated glycerides were elucidated by liquid chromatography-quadrupole time-of-flight chromatograph mass spectrometer (LC–Q/TOF) and NMR spectroscopy. The hydrate type of M-glyceride was detected as a minor component by LC–MS/MS. By 2D-NMR experiments, peaks I of the intact M-glyceride were elucidated as 1,2-didocosapentaenoyl-glyceryl-2′-oxy-3′-oxomorpholino propionic acid, and peak II was estimated 1,2-palmitoyldocosapentaenoyl- and/or 1,2-docosapentaenoylpalmitoyl-glyceryl-2′-oxy-3′-oxomorpholino propionic acid. The double bond position of docosapentaenoic acid was of the ω − 6 type (C₂₂ = 5.ω − 6). The M-glyceride content varied by the cell cycle. The content was 0.4% of lyophilized cells at the mid logarithmic phase, and decreased to 0.1% at the mid stationary phase. When cells were grown in 1.0 µM M-glyceride-containing growth media, cell growth was stimulated to 110% of the control. With 0.1 µM acetyl M-glyceride, stimulation of 113% of the control was observed. Finding morpholine derivatives in biological components is rare, and 2-hydroxy-3-oxomorpholino propionic acid (auranic acid) is a novel morpholine derivative.

The Influence of the COVID-19 Pandemic on Physical Activity and New Incidence of Frailty among Initially Non-Frail Older Adults in Japan: A Follow-Up Online Survey

OBJECTIVES

The objective of this study was to investigate the influence of the COVID-19 pandemic on physical activity (PA) and the incidence of frailty among initially non-frail older adults in Japan.

DESIGN

A follow-up online survey.

SETTING AND SUBJECTS

Among the 1,600 baseline online survey participants, 388 adults were already frail, and 275 older adults did not respond to the follow-up survey. Thus, the final number of participants in this study was 937 (follow-up rate: 77.3%).

METHODS

We assessed the total PA time at four time points according to the COVID-19 waves in Japan: January 2020 (before the pandemic), April 2020 (during the first wave), August 2020 (during the second wave), and January 2021 (during the third wave). We then investigated the incidence of frailty during a one-year follow-up period (during the pandemic).

RESULTS

The total PA time during the first, second, and third waves of the pandemic decreased from the pre-pandemic PA time by 33.3%, 28.3%, and 40.0%, respectively. In particular, the total PA time of older adults who were living alone and socially inactive decreased significantly: 42.9% (first wave), 50.0% (second wave), and 61.9% (third wave) less than before the pandemic, respectively. Additionally, they were at a significantly higher risk of incident frailty than those who were not living alone and were socially active (adjusted odds ratio: 2.04 [95% confidence interval: 1.01-4.10]).

CONCLUSION

Our findings suggest that older adults who live alone and are socially inactive are more likely to experience incident frailty/disability due to decreased PA during the pandemic. Understanding this mechanism may be crucial for maintaining the health status of older adults.

The Mass of Geniohyoid Muscle Is Associated with Maximum Tongue Pressure and Tongue Area in Patients with Sarcopenic Dysphagia

OBJECTIVES

We investigated the associations about the mass of geniohyoid and tongue muscle and the maximum tongue pressure in patients with sarcopenic dysphagia using ultrasonography.

DESIGN

Cross sectional study.

SETTING

5 hospitals including 3 acute and 2 rehabilitation hospitals and 1 older facility.

PARTICIPANTS

36 inpatients with sarcopenic dysphagia.

MEASUREMENTS

Ultrasonography was performed for geniohyoid muscle and tongue. The area for geniohyoid and tongue muscles in sagittal plane and the mean brightness level (0-255) in the muscle area were calculated. Maximum tongue pressure as strength of swallowing muscle were investigated. Partial correlation coefficient and multiple regression analysis adjusting for age and sex were performed.

RESULTS

The mean age was 81.1 ± 7.9. Men were 23. The mean BMI was 19.0 ± 4.1. The mean maximum tongue pressure was 21.3 ± 9.3 kPa. The mean cross sectional area for geniohyoid muscles was 140 ± 47 mm2. The mean brightness for geniohyoid muscle was 18.6 ± 9.0. The mean cross sectional area for tongue muscles was 1664.1 ± 386.0 mm2. The mean brightness for tongue muscles was 34.1 ± 10.6. There was a significant positive correlation between area of geniohyoid muscle and maximum tongue pressure (r = 0.38, p = 0.04). Geniohyoid muscle area was an explanatory factor for maximum tongue pressure (p = 0.012) and tongue muscle area (p = 0.031) in multivariate analysis.

CONCLUSIONS

Geniohyoid muscle mass was an independent explanatory factor for maximum tongue pressure and tongue muscle mass.