Comparative pathogenesis of type 1 (European genotype) and type 2 (North American genotype) porcine reproductive and respiratory syndrome virus in infected boar

Background : Porcine reproductive and respiratory syndrome virus (PRRSV) now has two main genotypes, genotype 1 (European) and genotype 2 (North American). There is a lack of data on the comparison of pathogenicity of the two genotypes in boars. The objectives of the present study were to evaluate the amount of PRRSV present in semen over time and compare the viral distribution and microscopic lesions of type 1 and type 2 PRRSV-infected boars. Methods : Twenty-four 8-month-old PRRSV-naïve Duroc boars were randomly allocated to 3 treatment groups. The boars in groups 1 (n = 9) and 2 (n = 9) were intranasally inoculated with type 1 or type 2 PRRSV, respectively. The boars in groups 1 (n = 6) served as negative controls. Semen and blood samples were collected up to 35 days post-inoculation (dpi), and necropsies were performed on 14, 21, and 35 dpi. Results : There were no significant differences in the genomic copy number of PRRSV, microscopic testicular lesion score, number of PRRSV-positive germ cells, or number of apoptotic cells between the type 1 and type 2 PRRSV-infected boars throughout the experiment. Histopathological changes were manifested by the desquamation of spermatocytes and the presence of multinucleated giant cells in seminiferous tubules of both type 1 and type 2 PRRSV-infected boars. The distribution of PRRSV-positive cells was focal; the virus was found in single germ cells or small clusters of germ cells, localized to the spermatogonia, spermatocytes, spermatids, and non-sperm cells in type 1 and type 2 PRRSV-infected boars. Conclusions : The results of this study demonstrated that two genotypes of PRRSV do not have significantly different virulence toward the male reproductive system of pigs.This research was supported by contract research funds of the Research Institute for Veterinary Science (RIVS) from the College of Veterinary Medicine and by Brain Korea 21 Program for Veterinary Science in the Republic of Korea.Peer Reviewe

Increased fucosyl glycoconjugate by Mycoplasma hyopneumoniae enhances adherences of Pasteurella multocida type A in the ciliated epithelial cells of the respiratory tract

BACKGROUND: The objective of this study was to elucidate the pathogenic mechanisms of how Mycoplasma hyopneumoniae enhances secondary Pasteurella multocida type A infection which leads to porcine enzootic pneumonia in infected pigs. Sixteen pigs were experimentally infected with M. hyopneumoniae and then euthanized at 7, 14, 21 and 28 days post inoculation. In situ hybridization for M. hyopneumoniae DNA and Ulex europaeus agglutinin-I (UEA-I) lectin histochemistry for fucosyl glycoconjugate, was performed in serial lung sections to determine alteration of fucosyl glycoconjugate in M. hyopneumoniae-infected bronchial and bronchiolar epithelium. Bacterial overlay assay was performed to determine the affinity of P. multocida type A with L-fucose. RESULTS: The luminal surface of bronchial and bronchiolar epithelial cells that were stained with UEA-I always showed hybridization signals for M. hyopneumoniae but it was negative in the unaffected parts of the lung from M. hyopneumoniae-infected pigs and in lung from negative control pigs. Colocalization of M. hyopneumoniae and UEA-I was especially prominent in the luminal surface of bronchial and bronchiolar epithelial cells in serial section of lung. The mean number of M. hyopneumoniae-positive cells correlated with the mean number of UEA-I-positive cells in lungs from infected pigs throughout the experiment. All eight P. multocida type A isolates from naturally occurring enzootic pneumonia, bound strongly at levels of 2 μg and 5 μg of L-fucose. CONCLUSIONS: The results of the present study demonstrate that M. hyopneumoniae increases the L-fucose composition to enhance adherence of P. multocida type A to the bronchial and bronchiolar epithelial cells

Targeting the stress support network regulated by autophagy and senescence for cancer treatment

Autophagy and cellular senescence are two potent tumor suppressive mechanisms activated by various cellular stresses, including the expression of activated oncogenes. However, emerging evidence has also indicated their pro-tumorigenic activities, strengthening the case for the complexity of tumorigenesis. More specifically, tumorigenesis is a systemic process emanating from the combined accumulation of changes in the tumor support pathways, many of which cannot cause cancer on their own but might still provide excellent therapeutic targets for cancer treatment. In this review, we discuss the dual roles of autophagy and senescence during tumorigenesis, with a specific focus on the stress support networks in cancer cells modulated by these processes. A deeper understanding of such context-dependent roles may help to enhance the effectiveness of cancer therapies targeting autophagy and senescence, while limiting their potential side effects. This will steer and accelerate the pace of research and drug development for cancer treatment.N

Subclinical vascular inflammation in subjects with normal weight obesity and its association with body Fat: an 18 F-FDG-PET/CT study

BACKGROUND: Although body mass index (BMI) is the most widely accepted parameter for defining obesity, recent studies have indicated a unique set of patients who exhibit normal BMI and excess body fat (BF), which is termed as normal weight obesity (NWO). Increased BF is an established risk factor for atherosclerosis. However, it is unclear whether NWO subjects already have a higher degree of vascular inflammation compared to normal weight lean (NWL) subjects; moreover, the association of BF with vascular inflammation in normal weight subjects is largely unknown. METHODS: NWO and NWL subjects (n = 82 in each group) without any history of significant vascular disease were identified from a 3-year database of consecutively recruited patients undergoing (18) F-fluorodeoxyglucose positron emission tomography/computed tomography ((18) F-FDG-PET/CT) at a self-referred Healthcare Promotion Program. The degree of subclinical vascular inflammation was evaluated using the mean and maximum target-to-background ratios (TBRmean and TBRmax) of the carotid artery, which were measured by (18) F-FDG-PET/CT (a noninvasive tool for assessing vascular inflammation). RESULTS: We found that metabolically dysregulation was greater in NWO subjects than in NWL subjects, with a significantly higher blood pressure, higher fasting glucose level, and worse lipid profile. Moreover, NWO subjects exhibited higher TBR than NWL subjects (TBRmean: 1.33 ± 0.16 versus 1.45 ± 0.19, p < 0.001; TBRmax: 1.52 ± 0.23 versus 1.67 ± 0.25, p < 0.001). TBR was significantly associated with total BF (TBRmean: r = 0.267, p = 0.001; TBRmax: r = 0.289, p < 0.001), age (TBRmean: r = 0.170, p = 0.029; TBRmax: r = 0.165, p = 0.035), BMI (TBRmean: r = 0.184, p = 0.018; TBRmax: r = 0.206, p = 0.008), and fasting glucose level (TBRmean: r = 0.157, p = 0.044; TBRmax: r = 0.182, p = 0.020). In multiple linear regression analysis, BF was an independent determinant of TBRmean and TBRmax, after adjusting for age, BMI, and fasting glucose level (TBRmean: regression coefficient = 0.020, p = 0.008; TBRmax: regression coefficient = 0.028, p = 0.005). Compared to NWL, NWO was also independently associated with elevated TBRmax values, after adjusting for confounding factors (odds ratio = 2.887, 95% confidence interval 1.206–6.914, p = 0.017). CONCLUSIONS: NWO is associated with a higher degree of subclinical vascular inflammation, of which BF is a major contributing factor. These results warrant investigations for subclinical atherosclerosis in NWO patients

Suppression of lung cancer progression by biocompatible glycerol triacrylate–spermine-mediated delivery of shAkt1

Background: Polyethylenimine (PEI)-based nonviral gene-delivery systems are commonly employed because of their high transfection efficiency. However, the toxic nature of PEI is a significant obstacle in clinical gene therapy. In this study, we developed biocompatible glycerol triacrylate-spermine (GT-SPE) polyspermine as a nanosized gene carrier for potential lung cancer gene therapy. Methods: The GT-SPE was synthesized using the Michael addition reaction between GT and SPE. The molecular weight was characterized using gel permeability chromatography multiangle laser light scattering and the composition of the polymer was analyzed using proton nuclear magnetic resonance. Results: The GT-SPE successfully protected the DNA from nucleases. The average particle size of the GT-SPE was 121 nm with a zeta potential of +23.45 mV. The GT-SPE was found to be less toxic than PEI for various cell lines, as well as for a murine model. Finally, our results showed that the GT-SPE/small hairpin Akt1 (shAkt1) complex suppressed lung tumorigenesis in a K-ras(LA1) lung cancer mice model by inducing apoptosis through the Akt signaling pathway and cell cycle arrest. Aerosol delivered GT-SPE/shAkt1, which reduced matrix metalloproteinase-9 activity and suppressed the expression levels of proliferating cell nuclear antigen, as well as vascular endothelial growth factors and CD31, which are known proliferation and angiogenesis markers, respectively. Conclusion: Our data suggest that GT-SPE may be a candidate for short hairpin-shaped RNA-based aerosol lung cancer gene therapy

Sclerostin inhibits Wnt signaling through tandem interaction with two LRP6 ectodomains

Low-density lipoprotein receptor-related protein 6 (LRP6) is a coreceptor of the beta -catenin-dependent Wnt signaling pathway. The LRP6 ectodomain binds Wnt proteins, as well as Wnt inhibitors such as sclerostin (SOST), which negatively regulates Wnt signaling in osteocytes. Although LRP6 ectodomain 1 (E1) is known to interact with SOST, several unresolved questions remain, such as the reason why SOST binds to LRP6 E1E2 with higher affinity than to the E1 domain alone. Here, we present the crystal structure of the LRP6 E1E2-SOST complex with two interaction sites in tandem. The unexpected additional binding site was identified between the C-terminus of SOST and the LRP6 E2 domain. This interaction was confirmed by in vitro binding and cell-based signaling assays. Its functional significance was further demonstrated in vivo using Xenopus laevis embryos. Our results provide insights into the inhibitory mechanism of SOST on Wnt signaling. The low-density lipoprotein receptor-related protein 6 (LRP6) is a co-receptor of the beta -catenin-dependent Wnt signaling pathway and interacts with the Wnt inhibitor sclerostin (SOST). Here the authors present the crystal structure of SOST in complex with the LRP6 E1E2 ectodomain construct, which reveals that the SOST C-terminus binds to the LRP6 E2 domain, and further validate this binding site with in vitro and in vivo experiments.Y

Risk Factors Influencing Cyberbullying Perpetration among Middle School Students in Korea: Analysis Using the Zero-Inflated Negative Binomial Regression Model

This cross-sectional descriptive study identified risk factors and predictors related to the perpetration of and potential for cyberbullying among adolescents, respectively. The analysis included a zero-inflated negative binomial regression model. Data were assessed from 2590 middle-school student panels obtained during the first wave of the Korean Child and Youth Panel Survey 2018. Of these respondents, 63.7% said they had not experienced the perpetration of cyberbullying. However, a subsequent count model analysis showed that several factors were significantly associated with cyberbullying, including offline delinquency, aggression, smartphone dependency, and smartphone usage on weekends (either 1–3 h or over 3 h). A logit model analysis also showed several predictive factors that increased the likelihood of cyberbullying, including gender (boys), offline delinquency, aggression, smartphone usage during weekdays (1–3 h), computer usage during weekends (1–3 h), and negative parenting. These identified risks and predictors should be useful for interventions designed to prevent the perpetration of cyberbullying among middle school students

Components Analysis on Audio Signal Mixtures

This paper presents a novel multi-label noise classification algorithm that uses a convolutional neural network and applies a sliding window for classification. The existing noise classification method uses a convolutional neural network, in which the input audio must have a fixed time length. On the other hand, time-variant networks such as a time-delay neural network or a recurrent neural network can use any length of time, but have a limitation of classifying only a single label within a short time. Considering such shortcomings, we propose a windowing method that applies multi-label classification in overlapping time windows. For an audio stream with a duration that is longer than the audio stream inputs that the model trained with, the model applies a sliding window with multi-label classification to detect the corresponding classes in each time sequence. The model then identifies the final classes of the input by considering the confidence scores of each output label in each time sequence. The classification accuracy was 94.17% for single-label audio, 85.21% for two-class audio, and averaged 86.39% for audio of various durations.1