Inhibition of lysozyme lytic activity by Ivy derived from Photobacterium damselae subsp. piscicida.

A pseudotuberculosis pathogen, Photobacterium damselae subsp. piscicida (Pdp), has caused enormous economic damage to yellowtail aquaculture in Japan. The Ivy gene has been discovered in plasmid of Pdp, and it has been proposed that it may help bacteria evade lysozyme-mediated lysis during interaction with an animal host. However, the lysozyme-inhibiting activity of Pdp-derived Ivy (Ivy-Pdp) is unknown, and it is unclear whether it acts as a virulence factor for host biophylaxis. In this study, the inhibitory effect of Ivy-Pdp on lysozyme was evaluated by expressing and purifying the recombinant Ivy-Pdp protein (rIvy-Pdp). The rIvy-Pdp protein inhibited hen egg white lysozyme activity in an rIvy-Pdp-concentration-dependent manner, and its inhibitory effect was similar under different temperature and pH conditions. The serum and skin mucus of the yellowtail (which is the host species of Pdp), Japanese flounder, and Nile tilapia showed bacteriolytic activity. In contrast, the addition of rIvy-Pdp inhibited the lytic activity in the serum of these fish species. In particular, it significantly inhibited lytic activity in the serum and skin mucus of Nile tilapia. On the basis of these results, we suggest that Ivy-Pdp is a temperature- and pH-stable lysozyme inhibitor. Additionally, Ivy-Pdp inhibited the lytic activity of lysozyme, which is involved in host biophylaxis. In summary, we inferred that Ivy-Pdp is an important factor that diminishes the sterilization ability of C-type lysozyme when Pdp infects the host.

Effects of Short-term Exposure to Ambient Particulate Matter on the Lung Function of School Children in Dhaka, Bangladesh.

BACKGROUND: Ambient particulate pollution may adversely affect children's lung function. However, evidence on this association remains scarce in Asia despite this region having the greatest burden of disease due to air pollution. OBJECTIVES: To investigate the effect of short-term exposure to ambient particulate matter (PM) on the lung function of school children in Dhaka city, Bangladesh. The possible seasonal modification of this association was also examined. METHODS: A panel of 315 school children who were 9-16 years of age were recruited from three schools in and around Dhaka. Lung function was assessed using a spirometry test during the cool and warm seasons in 2013, yielding six measurements per child. Daily PM data were retrieved from nearby air monitoring stations. Linear mixed effects models were used to examine associations. Seasonal modification was examined by stratification. RESULTS: An inverse association was observed for the lung function parameters with PM2.5; peak expiratory flow (PEF) and forced expiratory volume within 1 second (FEV1) decreased with increasing PM2.5. The percent deviation from the personal median was -4.19% [95% confidence interval (CI): -5.72, -2.66] for PEF and -2.05% (95% CI: -2.92, -1.18) for FEV1 for a 20 µg/m increase in PM2.5 on the previous day. Results for PM10 were less consistent. The estimated effects of PM on lung functions were generally greater in the warm season. CONCLUSIONS: Short-term exposure to PM is associated with worse lung function in children living in highly polluted settings, with the strength of these adverse PM effects varying by season.

Relationship between the risk for a shrimp allergy and freshness or cooking.

Tropomyosins are defined as risk factors for shrimp allergy. However, their concentration in different preparations has not been clarified. We quantified the tropomyosin concentration in shrimp meat, which was cooked using several methods or was stored under various conditions. The results demonstrated that shrimp meat from various preparations and storage conditions maintained tropomyosin concentrations that were sufficient to cause food allergies.

Pattern recognition receptors involved in the immune system of hagfish (Eptatretus burgeri).

The initial defense against invading pathogenic microbes is the activation of innate immunity by binding of pattern recognition receptors (PRRs) to pathogen associated molecular patterns (PAMPs). To explain the action of PRRs from hagfish, one of the extant jawless vertebrates, we purified the GlcNAc recognition complex (GRC) from serum using GlcNAc-agarose. The GRC comprises four proteins of varying molecular masses: 19 kDa, 26 kDa, 27 kDa, and 31 kDa. Exposure of Escherichia coli to the GRC led to the phagocytic activation of macrophages, revealing the opsonic function of the GRC. The GRC in serum formed a large complex with a molecular mass of approximately 1200 kDa. The GRC bound to Escherichia coli but not to rabbit red blood cells, despite both having GlcNAc on their surface. These structural and binding properties are similar to those of mannose-binding lectin (MBL). The amino acid sequence of a portion of the 31 kDa protein in the GRC matched the amino acid sequence of variable lymphocyte receptor (VLR)-B in some place. According to the Western blot analysis, the 31 kDa protein was recognized by the anti-hagfish VLR-B antiserum. Based on the results, it appears that the GRC functions as a PRR like MBL and that its 31 kDa protein has a structure similar to that of VLR-B.

Strength and Conditioning Programs to Increase Bat Swing Velocity for Collegiate Baseball Players.

Bat swing velocity (BSV) is an imperative element of a successful baseball hitting performance. This study aimed to investigate the anthropometric and physiological variables associated with BSV and explore strength and conditioning programs to increase BSV in collegiate baseball players. Seventy-eight collegiate baseball players (mean age ± SD, 19.4 ± 1.0 years) participated in this study. Maximum BSV (km/h) was measured using Blast Baseball (Blast Motion Inc., Carlsbad, CA, USA). The anthropometric and physiological variables measured were height, body mass, lean body mass, grip strength, back muscle strength, the 30 m sprint, standing long jump, and backward overhead medicine ball throwing. Analysis using Pearson's product-moment correlation coefficient showed a weak but significant positive correlation between all anthropometric measurements to BSV. Significant relationships existed between physiological variables of hand grip, back muscle strength, and backward overhead medicine ball throwing, but not the standing long jump and 30 m sprint. These data show that BSV is related to anthropometric and physiological variables, particularly upper and lower body strength and full-body explosive power. Based on the results of this study, we designed examples of sound training programs to increase BSV. Strength and conditioning coaches may want to consider using this information when designing a training program for collegiate baseball players.

A graph convolutional network for predicting COVID-19 dynamics in 190 regions/countries.

Introduction: Coronavirus disease (COVID-19) rapidly spread from Wuhan, China to other parts of China and other regions/countries around the world, resulting in a pandemic due to large populations moving through the massive transport hubs connecting all regions of China via railways and a major international airport. COVID-19 will remain a threat until safe and effective vaccines and antiviral drugs have been developed, distributed, and administered on a global scale. Thus, there is urgent need to establish effective implementation of preemptive non-pharmaceutical interventions for appropriate prevention and control strategies, and predicting future COVID-19 cases is required to monitor and control the issue. Methods: This study attempts to utilize a three-layer graph convolutional network (GCN) model to predict future COVID-19 cases in 190 regions and countries using COVID-19 case data, commercial flight route data, and digital maps of public transportation in terms of transnational human mobility. We compared the performance of the proposed GCN model to a multilayer perceptron (MLP) model on a dataset of COVID-19 cases (excluding the graph representation). The prediction performance of the models was evaluated using the mean squared error. Results: Our results demonstrate that the proposed GCN model can achieve better graph utilization and performance compared to the baseline in terms of both prediction accuracy and stability. Discussion: The proposed GCN model is a useful means to predict COVID-19 cases at regional and national levels. Such predictions can be used to facilitate public health solutions in public health responses to the COVID-19 pandemic using deep learning and data pooling. In addition, the proposed GCN model may help public health policymakers in decision making in terms of epidemic prevention and control strategies.

Acute effects of ambient temperature on lung function of a panel of school children living in Dhaka, Bangladesh.

INTRODUCTION: Short-term exposure to ambient temperature plays a significant role in human health. However, studies examining ambient temperature and lung function are scarce in locations with a tropical environment. To address this research gap, the current study investigated the effects of short-term ambient temperature on lung function in children and seasonal variation in this association in Dhaka, Bangladesh. METHODS: The study was conducted in three schools located in three cities inside and around Dhaka. Repeated lung function measurements were obtained from a panel of 315 school children (including 86 asthmatic children) aged 9-16 years in 2013. Linear mixed-effects models adjusted for potential confounders were used to examine the effect of ambient temperature on lung function. RESULTS: Short-term exposure to low ambient temperature was associated with a significant decrement in children's lung function. For each 1 °C decrease in daily mean temperature at cumulative lag of the current and previous day, lung function parameter values were -3.02% (95% CI, -1.69 to -4.35) for peak expiratory flow (PEF), and -1.48% (95% CI, -0.75 to -2.22) for forced expiratory volume within 1 s (FEV1). A significant seasonal variation was also observed in these associations, as the estimated adverse effects of decrease in daily mean temperature on lung function measures were primarily evident in winter. DISCUSSION: This study suggests that short-term ambient exposure to decrease in temperature adversely affect lung function. A significant seasonal modification in the association between temperature and lung function was also observed for these children living in an environment with a tropical climatic condition as the adverse effect of decrease in ambient temperature was primarily observed in winter than in summer.

Effect of Ambient Temperature on Daily Nebulized Asthma Hospital Visits in a Tropical City of Dhaka, Bangladesh.

The acute effect of temperature on asthma morbidity in Bangladesh is not well understood. As climate varies extensively in different parts of the world, the relation between temperature and asthma might also differ. We investigated the association between temperature and asthma-related hospital visits in the tropical city of Dhaka. We analyzed information from a total of 5989 asthma patients who received ambulatory care in the form of nebulized medication at the National Asthma Center in Mohakhali, Dhaka from February to November 2013. A time-stratified case-crossover study was conducted to estimate the effect of daily temperature, with consideration of delayed effects and possible confounders such as relative humidity and political strikes. An inverse association was observed between temperature and the number of hospital visits. The effect was delayed for approximately a week. A degree centigrade decrease in mean temperature (averaged across lags 0-6) was associated with an increase of approximately 4.5% (95% CI 1.5, 7.5) in all asthma visits. The association was evident in adult males but marginal in elderly males. A positive association (lag 0) was observed among adult females, whereas no association was observed among children. Strikes significantly modified the effect among the elderly. Findings suggest temperature declines affect asthma outcomes in a warm climate, and this effect can be delayed and vary by sex and age group.

Histopathological and ultrastructural features of Koi herpesvirus (KHV)-infected carp Cyprinus carpio, and the morphology and morphogenesis of KHV.

Epizootics of Koi herpesvirus (KHV) cause mass mortalities in koi carp and common carp worldwide. We used a newly developed 'per-gill infection' procedure with live KHV, and then conducted detailed histopathological and ultrastructural studies of KHV-infected cells including an examination of the morphology and morphogenesis of KHV. The primary target of KHV was respiratory epithelial cells of the gill lamellae, and release of virions from infected epithelial cells resulted in a systemic infection affecting the kidney, spleen, heart, brain and liver. The pathognomonic feature of infected cells was the formation of intranuclear inclusion bodies with marginal hyperchromatosis in the nucleus. Within the nucleus, assembly of capsids and nucleocapsids and an increase in filamentous nucleoproteins were evident. Enveloped nucleocapsids budded from the inner nuclear membrane into the perinuclear space. De-enveloped nucleocapsids were translocated in the cytoplasm to be embedded within inclusion bodies where tegumentation of the nucleocapsid occurred. Enveloped virions that had budded into intracytoplasmic vesicles and virions located extracellularly were composed of an electron-dense core, surrounded in turn by the capsid, the tegument and finally an envelope with projections. The morphology and morphogenesis of KHV were the same as those of viruses within the family Herpesviridae.

Detection of Japanese eel endothelial cells-infecting virus in Anguilla japonica elvers.

Japanese eel endothelial cells-infecting virus (JEECV) has spread in eel farms and caused serious economic loss. In this study, we examined the prevalence of JEECV infection in 100 wild Japanese eel (Anguilla japonica) elvers caught from Yamaguchi prefecture, Japan, using quantitative PCR and conventional PCR. Total genomic DNA was obtained from the cranial quarter of the body in 70 of 100 eels and from the gill in the remaining. Of 30 gill samples, 20 were analyzed after pooling with other samples, and the remaining 10 were analyzed separately. A single positive result for JEECV was detected following analysis of the 10 separately analyzed samples. This result constitutes the first report of JEECV infection in wild A. japonica elvers.

Short-term exposure to ambient particulate matter and emergency ambulance dispatch for acute illness in Japan.

Short-term exposure to air pollution may be linked to negative health outcomes that require an emergency medical response. However, few studies have been undertaken on this phenomenon to date. The aim of this study therefore was to examine the association between short-term exposure to ambient suspended particulate matter (SPM) and emergency ambulance dispatches (EADs) for acute illness in Japan. Daily EAD data, daily mean SPM and meteorological data were obtained for four prefectures in the Kanto region of Japan for the period from 2007 to 2011. The area-specific association between daily EAD for acute illness and SPM was explored using generalized linear models while controlling for ambient temperature, relative humidity, seasonality, long-term trends, day of the week and public holidays. Stratified analyses were conducted to evaluate the modifying effects of age, sex and medical conditions. Area-specific estimates were combined using meta-analyses. For the total study period the mean level of SPM was 23.7µg/m(3). In general, higher SPM was associated with a significant increase in EAD for acute illness [estimated pooled relative risk (RR): 1.008, 95% CI: 1.007 to 1.010 per 10µg/m(3) increase in SPM at lag 0-1]. The effects of SPM on EAD for acute illness were significantly greater for moderate/mild medical conditions (e.g. cases that resulted in <3weeks hospitalization or no hospitalization) when compared to severe medical conditions (e.g. critical cases, and cases that led to >3weeks hospitalization or which resulted in death). Using EAD data, this study has shown the adverse health effects of ambient air pollution. This highlights the importance of reducing the level of air pollution in order to maintain population health and well-being.