SARS-CoV-2 Variants and Age-Dependent Infection Rates among Household and Nonhousehold Contacts.

To determine the effects of age and variants of concern on transmission of SARS-CoV-2, we analyzed infection rates among close contacts over 4 periods in Toyama Prefecture, Japan. Among household contacts, odds of infection were 6.2 times higher during the period of the Omicron variant than during previous periods, particularly among children and adolescents.

LC3/FtMt Colocalization Patterns Reveal the Progression of FtMt Accumulation in Nigral Neurons of Patients with Progressive Supranuclear Palsy.

Mitochondrial ferritin (FtMt) is a mitochondrial iron storage protein associated with neurodegenerative diseases. In patients with progressive supranuclear palsy (PSP), FtMt was shown to accumulate in nigral neurons. Here, we investigated FtMt and LC3 in the post-mortem midbrain of PSP patients to reveal novel aspects of the pathology. Immunohistochemistry was used to assess the distribution and abnormal changes in FtMt and LC3 immunoreactivities. Colocalization analysis using double immunofluorescence was performed, and subcellular patterns were examined using 3D imaging and modeling. In the substantia nigra pars compacta (SNc), strong FtMt-IR and LC3-IR were observed in the neurons of PSP patients. In other midbrain regions, such as the superior colliculus, the FtMt-IR and LC3-IR remained unchanged. In the SNc, nigral neurons were categorized into four patterns based on subcellular LC3/FtMt immunofluorescence intensities, degree of colocalization, and subcellular overlapping. This categorization suggested that concomitant accumulation of LC3/FtMt is related to mitophagy processes. Using the LC3-IR to stage neuronal damage, we retraced LC3/FtMt patterns and revealed the progression of FtMt accumulation in nigral neurons. Informed by these findings, we proposed a hypothesis to explain the function of FtMt during PSP progression.

Detection of Legionella species, the influence of precipitation on the amount of Legionella DNA, and bacterial microbiome in aerosols from outdoor sites near asphalt roads in Toyama Prefecture, Japan.

BACKGROUND: Legionellosis is caused by the inhalation of aerosolized water contaminated with Legionella bacteria. In this study, we investigated the prevalence of Legionella species in aerosols collected from outdoor sites near asphalt roads, bathrooms in public bath facilities, and other indoor sites, such as buildings and private homes, using amoebic co-culture, quantitative PCR, and 16S rRNA gene amplicon sequencing. RESULTS: Legionella species were not detected by amoebic co-culture. However, Legionella DNA was detected in 114/151 (75.5%) air samples collected near roads (geometric mean ± standard deviation: 1.80 ± 0.52 log10 copies/m3), which was comparable to the numbers collected from bathrooms [15/21 (71.4%), 1.82 ± 0.50] but higher than those collected from other indoor sites [11/30 (36.7%), 0.88 ± 0.56] (P < 0.05). The amount of Legionella DNA was correlated with the monthly total precipitation (r = 0.56, P < 0.01). It was also directly and inversely correlated with the daily total precipitation for seven days (r = 0.21, P = 0.01) and one day (r = - 0.29, P < 0.01) before the sampling day, respectively. 16S rRNA gene amplicon sequencing revealed that Legionella species were detected in 9/30 samples collected near roads (mean proportion of reads, 0.11%). At the species level, L. pneumophila was detected in 2/30 samples collected near roads (the proportion of reads, 0.09 and 0.11% of the total reads number in each positive sample). The three most abundant bacterial genera in the samples collected near roads were Sphingomonas, Streptococcus, and Methylobacterium (mean proportion of reads; 21.1%, 14.6%, and 1.6%, respectively). In addition, the bacterial diversity in outdoor environment was comparable to that in indoor environment which contains aerosol-generating features and higher than that in indoor environment without the features. CONCLUSIONS: DNA from Legionella species was widely present in aerosols collected from outdoor sites near asphalt roads, especially during the rainy season. Our findings suggest that there may be a risk of exposure to Legionella species not only in bathrooms but also in the areas surrounding asphalt roads. Therefore, the possibility of contracting legionellosis in daily life should be considered.

A tandem repeat array in IG-DMR is essential for imprinting of paternal allele at the Dlk1-Dio3 domain during embryonic development.

Genomic imprinting is a phenomenon that causes parent-origin-specific monoallelic expression of a small subset of genes, known as imprinted genes, by parentally inherited epigenetic marks. Imprinted genes at the delta-like homolog 1 gene (Dlk1)-type III iodothyronine deiodinase gene (Dio3) imprinted domain, regulated by intergenic differentially methylated region (IG-DMR), are essential for normal development of late embryonic stages. Although the functions of IG-DMR have been reported by generating knockout mice, molecular details of the regulatory mechanisms are not fully understood as the specific sequence(s) of IG-DMR have not been identified. Here, we generated mutant mice by deleting a 216 bp tandem repeated sequence in IG-DMR, which comprised seven repeats of 24 bp motifs, by genome editing technologies. The mutant mice showed that paternal transmission of the deletion allele, but not maternal transmission, induces severe growth retardation and perinatal lethality, possibly due to placental defects. Embryos with a paternally transmitted deletion allele showed biallelic expression of maternally expressed genes and repression of paternally expressed genes. DNA methylation status also showed loss of methylation at IG-DMR and Gtl2-DMR, indicating that the tandem repeat sequence of IG-DMR is one of the functional sequences of IG-DMR, which is required for maintaining DNA methylation imprints of paternal allele at IG-DMR.

Are there gender differences in the association between body mass index and left ventricular diastolic function? A clinical observational study in the Japanese general population.

BACKGROUND: Increased body mass index (BMI) is a major risk factor for heart failure with preserved ejection fraction (HFpEF), and HFpEF is more prevalent in elderly females than males. We hypothesized that there may be gender differences in the association between BMI and echocardiographic left ventricular (LV) diastolic parameters. METHODS: We enrolled 456 subjects (243 males) without overt cardiac diseases, all of whom underwent a health checkup. Early (E) and late (A) diastolic transmitral flow velocity, early diastolic mitral annular velocity (e'), and left atrial (LA) volume index were measured by echocardiography to assess LV diastolic function. To examine gender differences in the association between BMI and LV diastolic function, we analyzed the interaction effects of gender on the association between BMI and echocardiographic LV diastolic parameters. RESULTS: Although there were significant gender differences in the association between BMI and E/A and e' in the crude model (interaction effect 0.037 and 0.173, respectively; P = .006 and .022, respectively), these differences were not statistically significant after adjustment for factors related to LV diastolic function. On the other hand, there were significant associations between BMI and LV diastolic parameters in each gender, even after adjustment. CONCLUSIONS: Our findings suggest there is no gender difference in the association between BMI and echocardiographic LV diastolic parameters. However, the association between BMI and LV diastolic parameters was significant in both genders. Controlling body weight might be beneficial for both women and men to prevent progression of LV diastolic dysfunction and development of HFpEF.

PACT/PRKRA and p53 regulate transcriptional activity of DMRT1.

The transcription factor DMRT1 (doublesex and mab-3 related transcription factor) has two distinct functions, somatic-cell masculinization and germ-cell development in some vertebrate species, including mouse and the African clawed frog Xenopus laevis. However, its transcriptional regulation remains unclear. We tried to identify DMRT1-interacting proteins from X. laevis testes by immunoprecipitation with an anti-DMRT1 antibody and MS/MS analysis, and selected three proteins, including PACT/PRKRA (Interferon-inducible double-stranded RNA dependent protein kinase activator A) derived from testes. Next, we examined the effects of PACT/PRKRA and/or p53 on the transcriptional activity of DMRT1. In transfected 293T cells, PACT/PRKRA and p53 significantly enhanced and repressed DMRT1-driven luciferase activity, respectively. We also observed that the enhanced activity by PACT/PRKRA was strongly attenuated by p53. Moreover, in situ hybridization analysis of Pact/Prkra mRNA in tadpole gonads indicated high expression in female and male germline stem cells. Taken together, these findings suggest that PACT/PRKRA and p53 might positively and negatively regulate the activity of DMRT1, respectively, for germline stem cell fate.

Use of Cardiac Imaging to Evaluate Cardiac Function and Pulmonary Hemodynamics in Patients with Heart Failure.

PURPOSE OF REVIEW: Noninvasive hemodynamic assessments in patients with heart failure (HF) are essential for appropriate diagnosis and establishment of the best treatment strategies. Recently, the impact of pulmonary circulation and right ventricular function on prognosis in HF patients has drawn increasing attention. In this article, we explore the usefulness of cardiac imaging for hemodynamic assessments, mainly focusing on echocardiographic evaluation. RECENT FINDINGS: The reliability of Doppler echocardiography as a noninvasive alternative to Swan-Ganz catheterization has been well investigated with higher than 80% accuracy for estimating pulmonary artery pressure. Strain measurement and three-dimensional echocardiography are useful for evaluating right ventricular function together with pulmonary circulation. The accuracy of analyzing left and right ventricular functions by cardiac computed tomography and cardiac magnetic resonate imaging has also been established. These modalities can provide myocardial tissue information and allow calculation of the extracellular volume fraction as well. According to the rapid improvement of technologies, cardiac imaging has become an essential tool for hemodynamic evaluation in HF management.

Epizootic Hemorrhagic Disease Virus Serotype 6 Infection in Cattle, Japan, 2015.

During October-December 2015, an epizootic hemorrhagic disease outbreak occurred in cattle in Japan. Forty-six animals displayed fever, anorexia, cessation of rumination, salivation, and dysphagia. Virologic, serologic, and pathologic investigations revealed the causative agent was epizootic hemorrhagic disease virus serotype 6. Further virus characterization is needed to determine virus pathogenicity.

Fluorine-19 magnetic resonance imaging probe for the detection of tau pathology in female rTg4510 mice.

Aggregation of tau into neurofibrillary tangles (NFTs) is characteristic of tauopathies, including Alzheimer's disease. Recent advances in tau imaging have attracted much attention because of its potential contributions to early diagnosis and monitoring of disease progress. Fluorine-19 magnetic resonance imaging (19 F-MRI) may be extremely useful for tau imaging once a high-quality probe has been formulated. In this investigation, a novel fluorine-19-labeling compound has been developed as a probe for tau imaging using 19 F-MRI. This compound is a buta-1,3-diene derivative with a polyethylene glycol side chain bearing a CF3 group and is known as Shiga-X35. Female rTg4510 mice (a mouse model of tauopathy) and wild-type mice were intravenously injected with Shiga-X35, and magnetic resonance imaging of each mouse's head was conducted in a 7.0-T horizontal-bore magnetic resonance scanner. The 19 F-MRI in rTg4510 mice showed an intense signal in the forebrain region. Analysis of the signal intensity in the forebrain region revealed a significant accumulation of fluorine-19 magnetic resonance signal in the rTg4510 mice compared with the wild-type mice. Histological analysis showed fluorescent signals of Shiga-X35 binding to the NFTs in the brain sections of rTg4510 mice. Data collected as part of this investigation indicate that 19 F-MRI using Shiga-X35 could be a promising tool to evaluate tau pathology in the brain.

Full genome sequence of a Sathuvachari virus strain isolated in the southwestern-most archipelago of Japan.

Two virus strains, tentatively designated as ON-6/P/05 and ON-7/E/05, were isolated from blood samples of healthy cattle in the Yaeyama Islands, located in the southwestern-most region of Japan, in 2005. Ultrastructural observations of infected baby hamster (BHK-21) cells revealed that the viruses had features consistent with those of orbivirus. As with other orbiviruses, the viral genome consists of 10 double-stranded RNA segments. The full genome sequence of ON-6/P/05 was determined and shared high nucleotide and amino acid identities (90.07-98.22% nucleotide identity; 96.16-99.72% amino acid identity) with that of Sathuvachari virus (SVIV), a member of the species Sathuvachari virus of the genus Orbivirus, originally isolated from starlings collected in southern India in 1963. The sequence of segment two of ON-7/E/05 was identical to that of ON-6/P/05. The isolation of SVIV from cattle also indicated that the virus has a wider host range than previously thought. The potential pathogenicity of SVIV in domestic animals should be considered in future disease surveillance within its distribution range.

Congenital Malformations of Calves Infected with Shamonda Virus, Southern Japan.

In 2015 and 2016, we observed 15 malformed calves that were exposed to intrauterine infection with Shamonda virus, a Simbu serogroup orthobunyavirus, in Japan. Characteristic manifestations were arthrogryposis and gross lesions in the central nervous system. Our results indicate that this arbovirus should be considered a teratogenic virus in ruminants.

Hierarchical axon targeting of Drosophila olfactory receptor neurons specified by the proneural transcription factors Atonal and Amos.

Sensory information is spatially represented in the brain to form a neural map. It has been suggested that axon-axon interactions are important for neural map formation; however, the underlying mechanisms are not fully understood. We used the Drosophila antennal lobe, the first olfactory center in the brain, as a model for studying neural map formation. Olfactory receptor neurons (ORNs) expressing the same odorant receptor target their axons to a single glomerulus out of approximately 50 glomeruli in the antennal lobe. Previous studies have showed that the axons of Atonal ORNs, specified by Atonal, a basic helix-loop-helix (bHLH) transcription factor, pioneer antennal lobe formation; however, the details remain to be elucidated. Here, we show that genetic ablation of Atonal ORNs affects antennal lobe structure and axon targeting of Amos ORNs, another type of ORN specified by the bHLH transcription factor Amos. During development, Atonal ORNs reach the antennal lobe and form the axon commissure before Amos ORNs. We also found that N-cadherin knockdown specifically in Atonal ORNs disrupts the glomerular boundary in the whole antennal lobe. Our results suggest that Atonal ORNs function as pioneer axons. Thus, correct axon targeting of Atonal ORNs is essential for formation of the whole antennal lobe.

Reconsideration of Inferior Vena Cava Parameters for Estimating Right Atrial Pressure in an East Asian Population　- Comparative Simultaneous Ultrasound-Catheterization Study.

BACKGROUND: Ultrasound measurements of the inferior vena cava (IVC) diameter (IVCD), together with its respiratory variation, provide a noninvasive estimate of right atrial pressure (RAP). However, there is a paucity of studies that have compared this technique with simultaneous catheterization. We explored the best cut-off values of IVC parameters for elevated RAP in comparison with RAP measured by catheterization.Methods and Results:We prospectively enrolled 120 East Asian patients who were scheduled for catheterization. The IVCD and IVC collapsibility index (IVCCI) were measured according to the current guidelines. The optimal maximum IVCD (IVCDmax) and IVCCI cut-offs for detecting elevated RAP (RAP ≥10 mmHg) were 17 mm and 40%, respectively. When we combined both in proportion to the guidelines, the sensitivity and specificity for detecting elevated RAP were 75% and 94%, respectively. When the cut-off values from the current guidelines (>21 mm and <50%) were applied, the respective sensitivity and specificity were 42% and 99%. Interestingly, the cut-off value of the optimal IVCDmax indexed by body surface area (11 mm/m2) was similar to previous Western population data. When we combined both cut-off values (11 mm/m2and 40%), the sensitivity and specificity were 75% and 95%, respectively. CONCLUSIONS: The optimal absolute IVCDmax and IVCCI cut-offs to detect elevated RAP were smaller than those in the current guidelines. Indexed IVCDmax may be an IVC parameter that can be used internationally.

Factors associated with postoperative requirement of renal replacement therapy following off-pump coronary bypass surgery.

Cardiopulmonary bypass usage provokes a systemic inflammatory response resulting in deterioration of renal function. However, risk factors for requiring renal replacement therapy (RRT) following off-pump coronary artery bypass graft surgery (CABG) have not yet been fully elucidated. We reviewed 718 consecutive patients undergoing elective off-pump CABG at our institution, excluding patients on chronic hemodialysis preoperatively. Sub-analysis of patients with preserved renal function, defined as a creatinine level below a cut-off value of 1.12 mg/dL (obtained by receiver operating characteristic curve), was also performed. Of the 718 patients, 41 (5.7 %) required RRT. There were 556 patients (77.4 %) with preserved renal function preoperatively, and 13 (2.4 %) of these required postoperative RRT. Multivariate analysis revealed that age (years) and preoperative serum creatinine (mg/dL) and brain natriuretic peptide (BNP) levels (pg/dL) were associated with RRT [odds ratios (OR) 1.052, 95 % confidence interval (CI) 9.064 and 1.001, respectively, all p < 0.05] in the total population, whereas low albumin concentration was the only independent predictor for RRT in patients with preserved renal function (OR 0.062, p < 0.0001). When creatinine levels were below 1.5 mg/dL, the predictive power of hypoalbuminemia for RRT requirement overwhelmed that of creatinine or BNP levels. Older age, preoperative elevated creatinine and BNP levels were associated with a requirement for RRT following off-pump CABG. In patients with preserved renal function, hypoalbuminemia was most significantly related to the RRT requirement.

The impact of surgical left atrial appendage amputation/ligation on stroke prevention in patients undergoing off-pump coronary artery bypass grafting.

Stroke is a major adverse event in patients developing atrial fibrillation (AF) after cardiac surgery. Surgical left atrial appendage amputation/ligation (LAA-A/L) during off-pump coronary artery bypass grafting (OPCAB) is routinely performed in our institution. We analyzed 578 consecutive patients (mean age 69 years, male 82%) undergoing OPCAB with or without concomitant LAA-A/L from 2011 to 2014 at our institution in a prospective observational manner. The safety and efficacy of the concomitant LAA-A/L on preventing early (<30 days) and overall postoperative stroke were examined. A total of 193 patients (33.4%) underwent LAA-A/L, consisting of amputation in 154 and ligation in 39 patients (80 and 20% of the cases, respectively). Preoperative characteristics, operative time, requirement of blood transfusion, and 30-day mortality were not significantly different between those with and without LAA-A/L. The incidences of postoperative AF and early and overall stroke were not significantly different between the groups in the analysis based on a total cohort. In a subanalysis of patients without LAA-A/L, early and overall stroke occurred more frequently in those developing postoperative AF than those without AF (2.8 vs. 0%; p = 0.005, 6.2 vs. 1.5%; p = 0.017, respectively), while in patients receiving LAA-A/L, stroke incidences did not differ between those with and without AF. Multivariate logistic regression showed postoperative AF without LAA-A/L as the only independent positive predictor of overall stroke (OR 3.69, p = 0.03). Concomitant LAA-A/L with OPCAB can safely prevent postoperative stroke occurrence in case patients develop AF, the most common arrhythmia associated with stroke.

Cord blood-derived endothelial colony-forming cell function is disrupted in congenital diaphragmatic hernia.

Vascular growth is necessary for normal lung development. Although endothelial progenitor cells (EPCs) play an important role in vascularization, little is known about EPC function in congenital diaphragmatic hernia (CDH), a severe neonatal condition that is associated with pulmonary hypoplasia. We hypothesized that the function of endothelial colony-forming cells (ECFCs), a type of EPC, is impaired in CDH. Cord blood (CB) was collected from full-term CDH patients and healthy controls. We assessed CB progenitor cell populations as well as plasma vascular endothelial growth factor (VEGF) and stromal cell-derived factor 1α (SDF1α) levels. CB ECFC clonogenicity; growth kinetics; migration; production of VEGF, SDF1α, and nitric oxide (NO); vasculogenic capacity; and mRNA expression of VEGF-A, fms-related tyrosine kinase 1 (FLT1), kinase insert domain receptor (KDR), nitric oxide synthase (NOS) 1-3, SDF1, and chemokine (C-X-C motif) receptor 4 (CXCR4) were also assessed. Compared with controls, CB ECFCs were decreased in CDH. CDH ECFCs had reduced potential for self-renewal, clonogenicity, proliferation, and migration. Their capacity for NO production was enhanced but their response to VEGF was blunted in CDH ECFCs. In vivo potential for de novo vasculogenesis was reduced in CDH ECFCs. There was no difference in CB plasma VEGF and SDF1α concentrations, VEGF and SDF1α production by ECFCs, and ECFC mRNA expression of VEGF-A, FLT1, KDR, NOS1-3, SDF1, and CXCR4 between CDH and control subjects. In conclusion, CB ECFC function is disrupted in CDH, but these changes may be caused by mechanisms other than alteration of VEGF-NO and SDF1-CXCR4 signaling.

Analysis of Skeletal Muscle Torque Capacity and Circulating Ceramides in Patients with Advanced Heart Failure.

BACKGROUND: Heart failure (HF)-related exercise intolerance is thought to be perpetuated by peripheral skeletal muscle functional, structural, and metabolic abnormalities. We analyzed specific dynamics of muscle contraction in patients with HF compared with healthy, sedentary controls. METHODS: Isometric and isokinetic muscle parameters were measured in the dominant upper and lower limbs of 45 HF patients and 15 healthy age-matched controls. Measurements included peak torque normalized to body weight, work normalized to body weight, power, time to peak torque, and acceleration and deceleration to maximum strength times. Body morphometry (dual energy X-ray absorptiometry scan) and circulating fatty acids and ceramides (lipodomics) were analyzed in a subset of subjects (18 HF and 9 controls). RESULTS: Extension and flexion time-to-peak torque was longer in the lower limbs of HF patients. Furthermore, acceleration and deceleration times in the lower limbs were also prolonged in HF subjects. HF subjects had increased adiposity and decreased lean muscle mass compared with controls. Decreased circulating unsaturated fatty acids and increased ceramides were found in subjects with HF. CONCLUSIONS: Delayed torque development suggests skeletal muscle impairments that may reflect abnormal neuromuscular functional coupling. These impairments may be further compounded by increased adiposity and inflammation associated with increased ceramides.

Relationship of Left Ventricular Diastolic Function to Obesity and Overweight in a Japanese Population With Preserved Left Ventricular Ejection Fraction.

BACKGROUND: Obesity has been found to be associated with future development of diastolic heart failure. Other evidence has indicated that the effect of obesity on left ventricular (LV) mass varies among ethnicities. However, there are few data on the relationship between body mass index (BMI) and LV diastolic dysfunction in the Japanese population. METHODS AND RESULTS: We performed echocardiography in 788 subjects without valvular disease or LV systolic dysfunction. They were divided into 3 groups by BMI: normal weight, overweight, and obese. We used multivariable linear regression analysis to assess the clinical variables associated with diastolic parameters, including BMI. We also assessed the risk of diastolic dysfunction associated with BMI using multivariable logistic models. Overweight and obese subjects had significantly worse LV diastolic function and greater LV mass than normal weight subjects. In the multivariable analysis, BMI was independently associated with diastolic parameters. Furthermore, after adjusting for clinical factors, the increased risks of diastolic dysfunction in overweight subjects (adjusted odds ratio: 2.02, 95% confidence interval 1.21-3.36) and obese subjects (4.85, 3.36-16.27) were greater than those previously observed in Western populations. CONCLUSIONS: The Japanese population might be more susceptible than Western subjects to the effect of BMI on LV diastolic function. Differences between ethnicities should be taken into consideration in strategies for the prevention of diastolic heart failure. (Circ J 2016; 80: 1951-1956).