Publications by authors named "An Chun Cheng"

Hepatic clearance has been widely studied for over 50 yr. Many models have been developed using either theoretical or empirical tests to predict drug metabolism. The well-stirred, parallel-tube, and dispersion metabolic models have been extensively discussed.

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Exosomes are small membrane vesicles that retain various substances such as proteins, nucleic acids, and small RNAs. Exosomes play crucial roles in many physiological and pathological processes, including innate immunity. Innate immunity is an important process that protects the organism through activating pattern recognition receptors (PRRs), which then can induce inflammatory factors to resist pathogen invasion.

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  • Riemerella anatipestifer is a gram-negative bacterium that primarily affects birds like ducks and turkeys, and a previous mutation system was established to study it using a pheS mutant marker.
  • The researchers created a streptomycin-resistant version of R. anatipestifer ATCC11845 and utilized the rpsL gene as a new counterselectable marker to perform markerless gene deletion of RA0C_1534, which is thought to play a role in the bacterium's response to oxidative stress.
  • The study found that the R. anatipestifer strain with the deleted RA0C_1534 gene was more sensitive to oxidative stress and that this gene's expression increases when exposed
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  • Riemerella anatipestifer (RA) is a harmful bacterial pathogen in ducks and birds, leading to high mortality rates and significant economic losses in the poultry sector.
  • The study developed a genetic manipulation method using a mutated pheS gene as a counterselectable marker, enabling the deletion of specific genes and the insertion of tags in the RA genome.
  • The new genetic techniques created in this research can help to better understand the biology and disease mechanisms of RA, and may also be applicable to other bacteria in the Flavobacteria family.
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Iron is one of the most important elements for bacterial survival and pathogenicity. The iron uptake mechanism of Riemerella anatipestifer (R. anatipestifer, RA), a major pathogen that causes septicemia and polyserositis in ducks, is largely unknown.

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To investigate tetracycline resistance and resistant genotype in , the tetracycline susceptibility of 212 isolates from China between 2011 and 2017 was tested. The results showed that 192 of 212 (90.6%) isolates exhibited resistance to tetracycline (the MICs ranged from 4 to 256 μg/ml).

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is an important pathogenic bacterium that infects ducks. It exhibits resistance to multiple classes of antibiotics. Multidrug efflux pumps play a major role as a mechanism of antimicrobial resistance in Gram-negative pathogens and they are poorly understood in .

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The Gram-negative bacterium Riemerella anatipestifer CH-2 is resistant to lincosamides, having a lincomycin (LCM) minimum inhibitory concentration (MIC) of 128 µg/mL. The G148_1775 gene of R. anatipestifer CH-2, designated lnu(H), encodes a 260-amino acid protein with ≤41% identity to other reported lincosamide nucleotidylyltransferases.

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One of the important elements for most bacterial growth is iron, the bioavailability of which is limited in hosts. (, RA), an important duck pathogen, requires iron to live. However, the genes involved in iron metabolism and the mechanisms of iron transport are largely unknown.

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Apoptosis, an important innate immune mechanism that eliminates pathogen-infected cells, is primarily triggered by two signalling pathways: the death receptor pathway and the mitochondria-mediated pathway. However, many viruses have evolved various strategies to suppress apoptosis by encoding anti-apoptotic factors or regulating apoptotic signalling pathways, which promote viral propagation and evasion of the host defence. During its life cycle, α-herpesvirus utilizes an elegant multifarious anti-apoptotic strategy to suppress programmed cell death.

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causes serositis and septicaemia in domestic ducks, geese, and turkeys. Traditionally, the antibiotics were used to treat this disease. Currently, our understanding of susceptibility to chloramphenicol and the underlying resistance mechanism is limited.

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Riemerella anatipestifer is an important bacterial pathogen in ducks and causes heavy economic losses in the duck industry. However, the pathogensis of this bacterium is poorly understood. In this study, a putative outer membrane hemin receptor gene B739_1208 in R.

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is a member of the family and a major causative agent of duck serositis. Little is known about its genetics and pathogenesis. Several bacteria are competent for natural transformation; however, whether is also competent for natural transformation has not been investigated.

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Article Synopsis
  • Duck enteritis virus (DEV) is part of the Alphaherpesvirinae family, with VP16 and pUL14 identified as important tegument proteins.
  • An indirect immunofluorescence assay (IFA) and bimolecular fluorescence complementation (BiFC) analysis showed that pUL14 interacts with and facilitates the nuclear import of VP16 in duck embryo fibroblasts (DEFs) during viral replication.
  • The study concluded that the N-terminal region of pUL14 (amino acids 1-98) contains a nuclear localization signal (NLS) essential for transporting VP16 into the nucleus, which is crucial for the DEV life cycle.
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Background/aims: The aminolycoside Gentamicin is a widely used antibiotic, applied in equine medicine. Despite its clinical use, concerns remain regarding the potential toxic side-effects, such as nephrotoxicity. Early detection of renal damage is critical in preclinical drug development.

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Riemerella anatipestifer is a duck pathogen that has caused serious economic losses to the duck industry worldwide. Despite this, there are few reported studies of the physiological and pathogenic mechanisms of Riemerella anatipestifer infection. In previous study, we have shown that TonB1 and TonB2 were involved in hemin uptake.

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Avian tuberculosis is a contagious disease affecting various domestic and wild bird species, and is caused by Mycobacterium avium . It is reported extremely rarely in commercial poultry flocks and has not been reported in commercial domestic ducks to date, with domestic ducks reported to be moderately resistant to M. avium infection.

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Mycobacterium avium is an important pathogenic bacterium in birds and has never, to our knowledge, reported to be isolated from domestic ducks. We present here the complete genome sequence of a virulent strain of Mycobacterium avium, isolated from domestic Pekin ducks for the first time, which was determined by PacBio single-molecule real-time technology.

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Background: Riemerella anatipestifer infection is a contagious disease that has resulted in major economic losses in the duck industry worldwide. This study attempted to characterize CRISPR-Cas systems in the disease-causing agent, Riemerella anatipestifer (R. anatipestifer).

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Duck hepatitis A virus 1 (DHAV-1) is the principal pathogen that causes duck viral hepatitis (DHV), a highly fatal infectious disease in ducklings. Given the importance of the humoral immune response in the clearance of DHAV-1, indirect enzyme-linked immunosorbent assays (I-ELISAs) to detect immune indices, including IgG, IgM and IgA1, were developed and evaluated in this study. The optimal concentrations of coating-antigen were 1.

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Riemerella anatipestifer is an important pathogenic bacterium in waterfowl and other avian species. We present here the genome sequence of R. anatipestifer RCAD0122, a multidrug-resistant strain isolated from infected ducks.

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Riemerella anatipestifer (R. anatipestifer) is one of the most important pathogens in ducks. The bacteria causes acute or chronic septicemia characterized by fibrinous pericarditis and meningitis.

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In order to investigate the relationship between the PD-1 pathway and impairment of immune responses with the CSFV infection, the mRNA expression of PD-1 and its ligands were evaluated by quantitative polymerase chain reaction (qPCR) during artificial CSFV infection. Simultaneously, expression of IL-2 and IL-10 mRNA were detected. The T cell proliferation and CSFV load in plasma were also measured.

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Gentamicin is a member of aminoglycosides, which has represented highly effective antimicrobial agents especially in Gram-negative infections despite their toxic effects in the kidney. Rapid diagnosis is vital to preserve renal function and to slow down renal injury. Owing to the poor sensitivity and specificity of serum creatinine (SCr) and blood urea nitrogen (BUN), new biomarkers for earlier and more accurate detection are needed.

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Acutobin isolated from Deinagkistrodon acutus venom has been used to prevent or treat stroke in patients. This defibrinogenating serine protease is a 39 kDa glycoprotein containing terminal disialyl-capped N-glycans. After sialidase treatment, the enzyme showed similar catalytic activities toward chromogenic substrate, and cleaved the Aα chain of fibrinogen as efficiently as the native acutobin did.

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