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Background: K1 capsular polysaccharide (CPS)-associated Klebsiella pneumoniae is the primary cause of pyogenic liver abscesses (PLA) in Asia. Patients with PLA often have serious complications, ultimately leading to a mortality of ~ 5%. This K1 CPS has been reported as a promising target for development of glycoconjugate vaccines against K. pneumoniae infection. The pyruvylation and O-acetylation modifications on the K1 CPS are essential to the immune response induced by the CPS. To date, however, obtaining the fragments of K1 CPS that contain the pyruvylation and O-acetylation for generating glycoconjugate vaccines still remains a challenge. Methods: We analyzed the digested CPS products with NMR spectroscopy and mass spectrometry to reveal a bacteriophage-derived polysaccharide depolymerase specific to K1 CPS. The biochemical and biophysical properties of the enzyme were characterized and its crystal structures containing bound CPS products were determined. We also performed site-directed mutagenesis, enzyme kinetic analysis, phage absorption and infectivity studies, and treatment of the K. pneumoniae-infected mice with the wild-type and mutant enzymes. Results: We found a bacteriophage-derived polysaccharide lyase that depolymerizes the K1 CPS into fragments of 1–3 repeating trisaccharide units with the retention of the pyruvylation and O-acetylation, and thus the important antigenic determinants of intact K1 CPS. We also determined the 1.46-Å-resolution, product-bound crystal structure of the enzyme, revealing two distinct carbohydrate-binding sites in a trimeric β-helix architecture, which provide the first direct evidence for a second, non-catalytic, carbohydrate-binding site in bacteriophage-derived polysaccharide depolymerases. We demonstrate the tight interaction between the pyruvate moiety of K1 CPS and the enzyme in this second carbohydrate-binding site to be crucial to CPS depolymerization of the enzyme as well as phage absorption and infectivity. We also demonstrate that the enzyme is capable of protecting mice from K1 K. pneumoniae infection, even against a high challenge dose. Conclusions: Our results provide insights into how the enzyme recognizes and depolymerizes the K1 CPS, and demonstrate the potential use of the protein not only as a therapeutic agent against K. pneumoniae, but also as a tool to prepare structurally-defined oligosaccharides for the generation of glycoconjugate vaccines against infections caused by this organism. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sugarcane is the most important sugar crop in the world. Like other crops, sugarcane suffers from herbivorous insect attack. The oriental armyworm Mythimna separata is a devastating pest of various crops in northeast Asia and an outbreak of this pest can result in substantial yield loss for sugarcane. However, the plant defense response situation is widely acquisition in model crops, but there is little information about how sugarcane plants defend themselves against this herbivore at the molecular and biochemical levels. RESULTS: We combined transcriptome and metabolomic analysis to investigate the changes in gene expression and metabolic processes that occurred in sugarcane plants after continuous feeding by M. separata larvae for 12 and 24 h. We identified 13 662 genes and 55 metabolites that were differentially regulated in sugarcane plants fed on by M. separata. The genes involved in phytohormones, transcription factors, and kinase‐related were activated and metabolism compounds such as carbohydrate, amino acid, ferulic substances and glutathione were detected regulated in sugarcane defense response. Comparable analyses showed a close correspondence relationship among pathways of phenylalanine metabolism, phenylpropanoid biosynthesis, and flavonoid biosynthesis in transcript and metabolite profiles. Furthermore, a bioassay experiment was conducted to test the influence of up‐regulated metabolites on M. separata growth and found chlorogenic acid had a lethal effect. CONCLUSION: The results of our study greatly enhanced the understanding of the sugarcane‐induced defense response mechanism against herbivore infestation at the transcriptional and metabolic levels. Also make contributions to provide clues for development of green pest control method. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: As the three major arthropod-borne viruses, dengue virus (DENV), chikungunya virus (CHIKV), and zika virus (ZIKV) are posing a growing threat to global public health and socioeconomic development. Our study aimed to systematically review the global seroprevalences of these arboviruses from existing publications. Methods: Articles published between Jan 01, 2000 and Dec 31, 2019 in the databases of Embase, Pubmed and Web of Science were searched and collected. Countries or areas with known local presence of Aedes vector mosquitoes were included. Random effects model was utilized to estimate the pooled seroprevalences and the proportion of inapparent infection. Results: Out of 1375, a total of 133 articles involving 176,001 subjects were included for our analysis. The pooled seroprevalences of DENV, CHIKV and ZIKV were 38%, 25% and 18%, respectively; and their corresponding proportions of inapparent infections were 80%, 40% and 50%. The South-East Asia Region had the highest seroprevalences of DENV and CHIKV, while the Region of the Americas had the highest seroprevalence of ZIKV. The seroprevalences of DENV and CHIKV were similar when comparing developed and developing countries, urban and rural areas, or among different populations. In addition, we observed a decreased global seroprevalences in the new decade (2010–2019) comparing to the decade before (2000–2009) for CHIKV. For ZIKV, the positive rates tested with the nucleic acid detection method were lower than those tested with the antibody detection method. Lastly, numerous cases of dual seropositivity for CHIKV and DENV were reported. Conclusions: Our results revealed a varied prevalence of arbovirus infections in different geographical regions and countries, and the inapparent infection accounted an unneglected portion of infections that requires more attention. This study will shed lights on our understanding of the true burden of arbovirus infections and promote appropriate vaccination in the future. Author summary: DENV, CHIKV, and ZIKV infections are the three major neglected tropical diseases continually posing threats to the public health and the socioeconomic development in recent decades. Given a high fraction of inapparent infections of these viruses, it is necessary to obtain informative knowledge of the seroepidemiology of DENV, CHIKV, and ZIKV worldwide, so as to estimate the true burden of these diseases and evaluate effects on vaccine efficacy and uptake. Given the fact that the reported infection rates may vary greatly due to the measurement, criteria of inclusion, and etc, a systematic review with meta-analysis is essential to collect and summarize the seroepidemiologic evidence of these arboviruses. In this study, the geographical distributions of DENV, CHIKV, and ZIKV and the proportions of their inapparent infections were analyzed, which revealed an overall high disease burden to the world, especially in specific regions. The epidemiological features of these arboviruses were also characterized via comparisons made in different countries/areas, populations, and time periods. In addition, evidence on the co-infection of DENV and CHIKV was assessed. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a globally-distributed pollutant, toxic to humans and animals. Emissions are particularly high in Asia, and the source of exposure for humans there may also be different from other regions, including rice as well as fish consumption, particularly in contaminated areas. Yet the threats Asian wildlife face in rice-based ecosystems are as yet unclear. We sought to understand how Hg flows through rice-based food webs in historic mining and non-mining regions of Guizhou, China. We measured total Hg (THg) and methylmercury (MeHg) in soil, rice, 38 animal species (27 for MeHg) spanning multiple trophic levels, and examined the relationship between stable isotopes and Hg concentrations. Our results confirm biomagnification of THg/MeHg, with a high trophic magnification slope. Invertivorous songbirds had concentrations of THg in their feathers that were 15x and 3x the concentration reported to significantly impair reproduction, at mining and non-mining sites, respectively. High concentrations in specialist rice consumers and in granivorous birds, the later as high as in piscivorous birds, suggest rice is a primary source of exposure. Spiders had the highest THg concentrations among invertebrates and may represent a vector through which Hg is passed to vertebrates, especially songbirds. Our findings suggest there could be significant population level health effects and consequent biodiversity loss in sensitive ecosystems, like agricultural wetlands, across Asia, and invertivorous songbirds would be good subjects for further studies investigating this possibility. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the safety and tolerability of gadobutrol at the recommended dose in patients requiring contrast-enhanced magnetic resonance imaging/angiography (MRI/MRA) in the routine setting.Methods: GARDIAN prospectively enrolled 23,708 patients undergoing routine gadobutrol-enhanced MRI/MRA for approved indications at 272 study centres in Europe, Asia, North America, and Africa and monitored for adverse events.Results: Median gadobutrol dose was 0.11 mmol/kg body weight. The overall incidence of adverse drug reactions (ADRs) was 0.7 % (n = 170 patients), with similar incidences in patients with renal impairment or cardiac disease, from different geographic regions and in different gadobutrol dose groups. Patients at risk for contrast media reaction had an ADR incidence of 2.5 %. Five patients (0.02 %) experienced serious adverse events, four were drug-related. One patient experienced a fatal anaphylactoid shock, assessed to be related to injection of gadobutrol. The contrast quality of gadobutrol-enhanced images was rated by treating physicians as good or excellent in 97 % cases, with similar ratings in all patient subgroups and indications.Conclusions: The GARDIAN study shows that gadobutrol at the recommended dose is well tolerated across a large, diverse patient population.Key Points: • Gadobutrol at recommended dose shows low rates of adverse drug reactions • Gadobutrol demonstrates a uniform safety profile across diverse patient groups • Gadobutrol provides excellent contrast quality in routine practice. [ABSTRACT FROM AUTHOR]

Desertification and microplastic pollution are major environmental issues that impact the function of the ecosystem and human well-being of drylands. Land desertification may influence soil microplastics' abundance, transport, and distribution, but their distribution in the dryland deserts of Central Asia's Amu Darya-Aral Sea basin is unknown. Here, we investigated the abundance and distribution of microplastics in dryland desert soils from the Amu Darya River to the Aral Sea basin in Central Asia at a spatial scale of 1000 km and soil depths ranging from 0 to 50 cm. Microplastics were found in soils from all sample locations, with abundances ranging from 182 to 17841 items kg -1 and a median of 3369. Twenty-four polymers were identified, with polyurethane (PU, 37.3%), silicone resin (SR, 17.0%), and chlorinated polyethylene (CPE, 9.8%) accounting for 64.1% of all polymer types. The abundance of microplastics was significantly higher in deep (20-50 cm) soils than in surface (0-5, 5-20 cm) soils. The main morphological characteristics of the observed microplastics were small size (20-50 μm) and irregular particles with no round edges (mean eccentricity 0.65). The abundance was significantly and positively related to soil EC and TP. According to the findings, desertification processes increase the abundance of microplastic particles in soils and promote migration to deeper soil layers. Human activities, mainly grazing, may be the region's primary cause of desertification and microplastic pollution. Our findings provide new information on the diffusion of microplastics in drylands during desertification; these findings are critical for understanding and promoting dryland plastic pollution prevention and control., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Few studies have reported the burden of generalized pustular psoriasis (GPP), a severe and potentially life-threatening skin disease, especially at a national level., Objectives: The aim of this study is to estimate the nationwide burden of GPP in China and make a systemic review of the published data., Methods: We conducted a population-based study using Urban Basic Medical Insurance in China from 2012 to 2016. GPP cases were identified by primary diagnoses including the international classification of Diseases codes (ICD-10: L40.1 and ICD-9: 694.3). A systematic review was conducted using relevant databases up to January 2022., Results: The crude prevalence and incidence of GPP in 2016 were 1.403 (95% confidence interval [CI]: 1.115-1.691) and 0.629 (95% CI: 0.483-0.775) per 100,000 person-years, respectively. The rates were higher in males than in females for both prevalence (1.429 vs. 1.135) and incidence (0.635 vs. 0.520). The prevalence and incidence showed a bimodal age distribution, with the first peak occurring in the 0- to 3-year age-group and the second peak occurring in the 30- to 39-year age-group. The per capita total cost per year for 1 patient with GPP was 609.26 (± 45.77) US dollars. Seven studies were identified in a systematic review, according to which the prevalence (per 100,000) of GPP tended to be higher in Asian countries (0.746-8.178 in Japan and 12.230 in Korea) than in France (0.176), Sweden (6.25), and Brazil (0.7)., Conclusions: This is the largest study concerning the disease burden of GPP, and in this study, the prevalence seemed to be higher in Asia. Although the direct economic burden of GPP did not seem high during the study period, the future usage of biologics and the humanistic burden should also be considered for policy-related decision-making., (© 2023 S. Karger AG, Basel.)

Emerging evidence shows that interleukin (IL)-10 gene polymorphisms can regulate its expression level and thus influence person's susceptibility to preeclampsia. However, various published results were inconsistent. To explore the association between maternal IL-10 gene polymorphisms and preeclampsia, we performed a meta-analysis based upon 11 individual studies here. Our meta-analysis results indicated that IL-10 -819 C/T (C versus T, OR = 1.28, 95% CI = 1.08-1.50, P = 0.003) and -592 C/A (C versus A, OR = 1.28, 95% CI = 1.03-1.59, P = 0.03) polymorphisms were associated with preeclampsia. Although there was no overall association between -1082 A/G polymorphism and preeclampsia (G versus A, OR = 0.93, 95% CI = 0.77-1.13, P = 0.49), such association existed among Asian (G versus A, OR = 1.29, 95% CI = 1.04-1.60, P = 0.02) and South American (G versus A, OR = 0.72, 95% CI = 0.54-0.94, P = 0.02) populations in the subgroup analysis stratified by continents., (© 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

The aim of this study was to determine and examine the possible reasons for the difference in prostate cancer incidence between Asian men and North American men by literature review. Data regarding cancer incidence and mortality were obtained from the database of the International Agency for Research on Cancer (IARC). A literature review was conducted by studying related articles published in peer-reviewed journals such as the The New England Journal of Medicine, Journal of Clinical Oncology, A Cancer Journal for Clinicians and Asian Journal of Andrology. To evaluate the early diagnosis and survival rates, the mortality-to-incidence rate ratio (MR/IR) was calculated from the IARC data. By comparing prostate cancer data between Asian men and North American men, we found that differences in the incidence rate and MR/IR could be attributed largely to a lack of annual prostate cancer screening with serum prostate-specific antigen (PSA) in most Asian countries. It is likely that PSA screening also contributes significantly to the differences in prostate cancer mortality rates. Prostate cancer has the highest incidence rate among five common malignancies in Asian Americans. However, the MR/IR ratio of prostate cancer is the lowest among cancers. These data seem to further support the usefulness of PSA screening, even though the percentage of low risk cancers is greater in prostate cancer than in other cancers. The low incidence rate of prostate cancer does not reflect the actual statistics of this disease in Asia. The data from limited institutions in many Asian countries seem to bias the true incidence and mortality rates. To improve this situation, incorporating PSA screening for prostate cancer, as well as constructing a nationwide cancer registration system, will be helpful.