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1.
Infect Drug Resist ; 16: 6039-6052, 2023.
Article in English | MEDLINE | ID: mdl-37719646

ABSTRACT

Objective: To evaluate the resolution of chromosomal virulence D (chvD) as a novel marker for mycobacterial species identification. Methods: A segment of chvD (652 bp) was amplified by PCR from 63 mycobacterial reference strains, 163 nontuberculous mycobacterial clinical isolates, and 16 M. tuberculosis complex (MTBC) clinical isolates. A phylogenetic tree based on the reference strains was constructed by the neighbor-joining and IQ-tree methods. Comparative sequence analysis of the homologous chvD gene efficiently differentiated the species within the genus Mycobacterium. Slowly growing Mycobacterium (SGM) and rapidly growing Mycobacterium (RGM) were separated in the phylogenetic tree based on the chvD gene. Results: The sequence discrepancies were obvious between M. kansasii and M. gastri, M. chelonae and M. abscessus, and M. avium and M. intracellulare, none of which could be achieved by 16S ribosomal RNA (rRNA) homologous gene alignment. Furthermore, chvD manifested larger intraspecies diversity among members of M. intracellulare subspecies. A total of 174 of the 179 (97.21%) clinical isolates, consisting of 12 mycobacterial species, were identified correctly by chvD blast. Four M. abscessus subsp. abscessus were identified as M. abscessus subsp. bolletii by chvD. MTBC isolates were indistinguishable, because they showed 99.84%-100% homology. Conclusion: Homologous chvD is a promising gene marker for identifying mycobacterial species, and could be used for highly accurate species identification among mycobacteria.

2.
Eur J Histochem ; 66(4)2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36373350

ABSTRACT

Heart failure (HF) is often complicated by renal dysfunction. Tolvaptan and valsartan are two well-known agents for the treatment of HF. However, the role of tolvaptan/valsartan combination on HF with renal dysfunction remains unclear. To establish a mice model with HF with renal dysfunction, mice were intraperitoneally injected with doxorubicin (Dox). Echocardiogram was applied to assess the left ventricular function. Additionally, serum aldosterone (ALD) and angiotensin II (Ang II) level in mice were determined by ELISA. Meanwhile, western blot assay was used to evaluate the expressions of B cell lymphoma-2 (Bcl-2), Bcl-2 associated X (Bax) and cleaved caspase 3 in the heart and kidney tissues of mice. In this study, we found that compared to tolvaptan or valsartan alone treatment group, tolvaptan/valsartan combination obviously improved the left ventricular ejection fraction (LVEF) and the left ventricular fractional shortening (LVFS), and reduced serum ALD and Ang II level in Dox-treated mice. Additionally, tolvaptan/valsartan combination significantly prevented the inflammation and fibrosis of heart and kidney tissues in Dox-treated mice. Meanwhile, tolvaptan/valsartan combination notably inhibited the myocardial and renal cell apoptosis in Dox-treated mice via upregulation of Bcl-2 and downregulation of Bax and cleaved caspase 3, compared to the single drug treatment. Collectively, tolvaptan/valsartan combination could improve cardiac and renal functions, as well as prevent the fibrosis, inflammation and apoptosis of heart and kidney tissues in Dox-treated mice. Taken together, combining tolvaptan with valsartan might be a promising approach to achieve enhanced therapeutic effect for treatment of HF with renal dysfunction.


Subject(s)
Heart Failure , Kidney Diseases , Mice , Animals , Valsartan/pharmacology , Valsartan/therapeutic use , Tolvaptan/therapeutic use , Tolvaptan/pharmacology , Stroke Volume , Caspase 3 , Ventricular Function, Left/physiology , bcl-2-Associated X Protein , Heart Failure/chemically induced , Heart Failure/drug therapy , Doxorubicin/adverse effects , Kidney/metabolism , Fibrosis , Inflammation
3.
Front Immunol ; 13: 791799, 2022.
Article in English | MEDLINE | ID: mdl-35401532

ABSTRACT

Yersinia pestis, the cause of plague, is a newly evolved Gram-negative bacterium. Through the acquisition of the plasminogen activator (Pla), Y. pestis gained the means to rapidly disseminate throughout its mammalian hosts. It was suggested that Y. pestis utilizes Pla to interact with the DEC-205 (CD205) receptor on antigen-presenting cells (APCs) to initiate host dissemination and infection. However, the evolutionary origin of Pla has not been fully elucidated. The PgtE enzyme of Salmonella enterica, involved in host dissemination, shows sequence similarity with the Y. pestis Pla. In this study, we demonstrated that both Escherichia coli K-12 and Y. pestis bacteria expressing the PgtE-protein were able to interact with primary alveolar macrophages and DEC-205-transfected CHO cells. The interaction between PgtE-expressing bacteria and DEC-205-expressing transfectants could be inhibited by the application of an anti-DEC-205 antibody. Moreover, PgtE-expressing Y. pestis partially re-gained the ability to promote host dissemination and infection. In conclusion, the DEC-205-PgtE interaction plays a role in promoting the dissemination and infection of Y. pestis, suggesting that Pla and the PgtE of S. enterica might share a common evolutionary origin.


Subject(s)
Escherichia coli K12 , Salmonella enterica , Yersinia pestis , Animals , Bacterial Proteins/genetics , Cricetinae , Cricetulus , Plasminogen Activators
4.
Ann Noninvasive Electrocardiol ; 27(3): e12931, 2022 05.
Article in English | MEDLINE | ID: mdl-35174568

ABSTRACT

OBJECTIVE: To observe the changes of F waves on electrocardiograms (ECGs) in patients with persistent atrial fibrillation during the insertion of a peripherally inserted central catheter (PICC), and to analyze the application effect of the ECG method (through F wave changes) for guiding PICC tip positioning. METHODS: Seventy-two patients who met the inclusion criteria and needed a PICC catheter were selected as the research subjects. We observed waveforms in the ECGs when the tip of the catheter reached a predetermined position. The chest X-ray results were used as the gold standard to calculate the sensitivity and specificity, and judge the safety and accuracy of ECG-guided PICC tip positioning in patients with atrial fibrillation. RESULTS: Of the 72 patients, there was no significant difference between the ECG method and chest X-ray results (χ2 = 0.2, p > 0.05). Sixty-one patients had F wave changes on ECG and 10 had no obvious changes (X-ray results confirmed that five patients had a tip position that was too shallow, two had ectopic tip positions, and three were located in the correct place). The sensitivity of the method was 95.7% and the specificity was 80%. CONCLUSION: As the ECG baselines of patients with persistent atrial fibrillation were difficult to judge and the F wave was irregular, we found that the F wave was significantly higher than before catheter insertion and fell back while withdrawing the catheter, so the catheter should be fed until the F wave significantly increased as the correct position of the catheter tip.


Subject(s)
Atrial Fibrillation , Catheterization, Central Venous , Catheterization, Peripheral , Central Venous Catheters , Atrial Fibrillation/therapy , Catheterization, Central Venous/methods , Catheterization, Peripheral/methods , Electrocardiography/methods , Humans
5.
J Agric Food Chem ; 70(2): 598-606, 2022 Jan 19.
Article in English | MEDLINE | ID: mdl-34939413

ABSTRACT

Pungency is one of the most important mouthfeel characteristics that is primarily related to the sensory quality of distilled spirits. However, the chemical basis of pungency is still unclear. A set of Baijiu samples with different levels of pungency was characterized by sensory analysis and volatile compound analyses. Several esters, aldehydes, and acids significantly correlated with pungency. Ethyl hexanoate, ethyl acetate, 3-methylbutyl hexanoate, acetaldehyde, acetal, and 3-methylbutanal were confirmed to be the strongest contributors to the pungency of Baijiu by the two-alternative forced-choice test. Sensory recombination testing further revealed that the contribution of esters to pungency was much higher than that of the aldehydes, and acid compounds at low concentrations suppress the pungency perception. In this study, the importance of esters in the pungency of distilled spirits is first reported. The results provide an instructive basis for further research into optimizing the quality of products.


Subject(s)
Alcoholic Beverages , Odorants , Alcoholic Beverages/analysis , Odorants/analysis
6.
Food Res Int ; 147: 110493, 2021 09.
Article in English | MEDLINE | ID: mdl-34399489

ABSTRACT

Pungency is increasingly being recognized as an important factor of overall sensory quality, palatability, and consumer preference of distilled spirits. The characterization of pungency is necessary to evaluate the potential sensory quality of distilled spirits. In this study, the temporal profiles of pungency of Baijiu with different aging times were evaluated using time-intensity (TI) and temporal dominance of sensations (TDS) methods, considering both pungency intensity and pungency sub-qualities. TI results indicated significant differences in release rate of pungency during Baijiu consumption. Compared to young Baijiu, old Baijiu tend to show higher release rate of pungency, the areas under the curve and duration of pungency were significantly decreased in old Baijiu. The TDS results showed significant differences in the combination of dominant sub-qualities, as well as in the maximum dominance rates and the dominant duration of sub-qualities among Baijiu. The young Baijiu were mainly characterized by the dominant sub-qualities of "burning" and "numbing", whereas for old Baijiu, "burning", "prickle", and "drying" were dominant. The application of TI and TDS provided dynamic and temporal profiles of pungency to fully characterize pungency differences of distilled beverages.


Subject(s)
Sensation , Taste , Beverages , Consumer Behavior
7.
Foods ; 10(5)2021 May 17.
Article in English | MEDLINE | ID: mdl-34067651

ABSTRACT

Pungency is a crucial sensory feature that influences consumers' appreciation and preferences toward alcoholic beverages. However, the quantitation of pungency is challenging to achieve using sensory analysis because of persistence, accumulation, and desensitization to the pungency perception. This study aimed to design a novel pungency evaluation method based on the measurement of tongue surface temperature. An infrared thermal (IRT) imager technique for measuring tongue surface temperature was established. To validate its feasibility, the IRT technique was used to measure tongue surface temperatures after the tongue was stimulated by (1) water and Baijiu, (2) different concentrations of ethanol aqueous solution (10, 20, 30, 40, and 50%, v/v), (3) ethanol aqueous solution and Baijiu samples with the same ethanol content, and (4) 26 Baijiu samples with different pungency level. For all cases, tongue surface temperatures showed large differences as a result of the different stimulation. The results showed that the tongue surface temperature correlated with the pungency intensity obtained by the sensory analysis. The relationship between tongue surface temperature and pungency intensity was established by multiple linear regression analysis. The IRT technique was able to be a useful support tool to quantitatively predict the pungency of alcoholic beverages, based on the measurement of tongue surface temperature.

8.
Can J Infect Dis Med Microbiol ; 2021: 7865405, 2021.
Article in English | MEDLINE | ID: mdl-34093925

ABSTRACT

Neisseria gonorrhoeae (N. gonorrhoeae, gonococci, or GC), the etiologic agent of gonorrhea, is a human-obligate bacterial pathogen. The GC surface contains pili that mediate the adherence to host cells. Studies have shown that GC pili, coded by pilin genes, undergo remarkable changes during human experimental gonorrhea, possibly generated by DNA phase variation during infection. The question that arises is whether the changes in pilins can alter the adherence capacity of N. gonorrhoeae to host cells. In this study, six variants initially isolated from male volunteers infected with one single clone of GC were examined for their adherence patterns with human Chang conjunctiva cells. In this study, we showed that the variants showed distinct adherence patterns to this cell line under light microscopy and scanning electron microscopy. Moreover, two reisolates showed higher adherence capacities than that of the input strain. The results provide an additional example as to how the pilus variation may play a role in the pathogenesis of N. gonorrhoeae.

9.
J Med Microbiol ; 70(3)2021 Mar.
Article in English | MEDLINE | ID: mdl-33591245

ABSTRACT

Introduction. Shigella sonnei, the cause of bacillary dysentery, belongs to Gram-negative enteropathogenic bacteria. S. sonnei contains a 210 kb virulence plasmid that encodes an O-antigen gene cluster of LPSs. However, this virulence plasmid is frequently lost during replication. It is well-documented that after losing the O-antigen and becoming rough strains, the Gram-negative bacteria may express an LPS core on its surface. Previous studies have suggested that by using the LPS core, Gram-negative bacteria can interact with several C-type lectin receptors that are expressed on antigen-presenting cells (APCs).Hypothesis/Gap Statement. S. sonnei by losing the virulence plasmid may hijack APCs via the interactions of LPS-CD209/CD207.Aim. This study aimed to investigate if the S. sonnei rough strain, by losing the virulence plasmid, interacted with APCs that express C-type lectins of human CD207, human CD209a and mouse CD209b.Methodology. SDS-PAGE silver staining was used to examine the O-antigen expression of S. sonnei WT and its rough strain. Invasion assays and inhibition assays were used to examine the ability of S. sonnei WT and its rough strain to invade APCs and investigate whether CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Animal assays were used to observe the dissemination of S. sonnei.Results. S. sonnei did not express O-antigens after losing the virulence plasmid. The S. sonnei rough strain invades with APCs, including human dendritic cells (DCs) and mouse macrophages. CD209 and CD207 are receptors for phagocytosis of rough S. sonnei. Expression of the O-antigen reduces the ability of the S. sonnei rough strain to be disseminated to mesenteric lymph nodes and spleens.Conclusion. This work demonstrated that S. sonnei rough strains - by losing the virulence plasmid - invaded APCs through interactions with CD209 and CD207 receptors.


Subject(s)
Antigens, CD/immunology , Cell Adhesion Molecules/immunology , Dysentery, Bacillary/microbiology , Lectins, C-Type/immunology , Mannose-Binding Lectins/immunology , O Antigens , Plasmids , Receptors, Cell Surface/immunology , Shigella sonnei/pathogenicity , Virulence/genetics , Animals , CHO Cells , Cricetulus , Dendritic Cells/microbiology , Host-Pathogen Interactions , Humans , Macrophages/microbiology , Mice , O Antigens/genetics , O Antigens/metabolism , Shigella sonnei/genetics
10.
Bosn J Basic Med Sci ; 21(1): 71-80, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-31999938

ABSTRACT

Endothelial progenitor cell (EPC) transplantation is a safe and effective method to treat acute myocardial infarction (AMI). However, oxidative stress leads to the death of a large number of EPCs in the early stage of transplantation, severely weakening the therapeutic effect. Previous studies demonstrated that microRNAs regulate the biological function of EPCs. The aim of the current study was to investigate the effect of microRNA on the biological function of EPCs under oxidative stress. Quantitative reverse transcription PCR was performed to detect the expression of miR-126, miR-508-5p, miR-150, and miR-16 in EPCs from rats, among which miR-126 showed a relatively higher expression. Treatment with H2O2 decreased miR-126 expression in EPCs in a dose-dependent manner. EPCs were further transfected with miR-126 mimics or inhibitors, followed by H2O2 treatment. Overexpression of miR-126 enhanced the proliferation, migration, and tube formation of H2O2-treated EPCs. MiR-126 overexpression also inhibited reactive oxygen species and malondialdehyde levels and enhanced superoxide dismutase levels, as well as increased angiopoietin (Ang)1 expression and decreased Ang2 expression in H2O2-treated EPCs. Moreover, miR-126 participated in the regulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase 3ß (GSK3ß) and extracellular signal-regulated kinase 1/2 (ERK1/2) signaling in EPCs, where both pathways were activated after miR-126 overexpression in H2O2-treated EPCs. Overall, we showed that miR-126 promoted the biological function of EPCs under H2O2-induced oxidative stress by activating the PI3K/Akt/GSK3ß and ERK1/2 signaling pathway, which may serve as a new therapeutic approach to treat AMI.


Subject(s)
Endothelial Progenitor Cells/metabolism , MicroRNAs/metabolism , Signal Transduction , Animals , Cell Cycle Proteins/metabolism , Endothelial Progenitor Cells/transplantation , Glycogen Synthase Kinase 3 beta/metabolism , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Myocardial Infarction/therapy , Oxidative Stress , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats , Schizosaccharomyces pombe Proteins/metabolism
11.
Food Chem ; 331: 127335, 2020 Nov 30.
Article in English | MEDLINE | ID: mdl-32574944

ABSTRACT

Comprehensive 2D gas chromatography-time-of-flight mass spectrometry was combined with descriptive sensory analysis to elucidate the specificity of strong-aroma type Baijiu (Chinese liquor) from different regions, based on regionally distinct flavor characterized by chemical and sensory profiles. Numerous potential aroma compounds (262) were identified, among which 58 aroma compounds were significantly different between the samples from Sichuan and Jianghuai regions. Relationships between these potential aroma compounds and sensory attributes were investigated by partial least squares regression and network analysis. The compounds that dominantly contributed to the important sensory attributes were identified. The high pyrazines, furanoids, and carbonyls amounts contributed to the high intensities of the cellar, toasted, and grain aroma profiles of the Sichuan region samples, while the high ester and alcohol levels contributed to the fruity and floral aroma profiles of the Jianghuai region samples. This approach may have practical application in flavor characterization of other alcoholic beverages.


Subject(s)
Alcoholic Beverages/analysis , Food Analysis/methods , Gas Chromatography-Mass Spectrometry/methods , Odorants/analysis , Volatile Organic Compounds/analysis , China , Esters/analysis , Food Analysis/statistics & numerical data , Gas Chromatography-Mass Spectrometry/statistics & numerical data , Humans , Least-Squares Analysis , Multivariate Analysis , Pyrazines/analysis , Taste
12.
J Recept Signal Transduct Res ; 40(2): 126-132, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32003295

ABSTRACT

Chlamydia pneumonia (C.pn) is a common respiratory pathogen that is involved in human cardiovascular diseases and promotes the development of atherosclerosis in hyperlipidemic animal models. C.pn reportedly up-regulated lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) in endothelial cells. Recently, the anti-atherosclerotic activity of peroxisome proliferator-activated receptor γ (PPARγ) has been documented. In the present study, we investigated the effect of C.pn on LOX-1 expression in human umbilical vein endothelial cells (HUVECs) and identified the involvement of the PPARγ signaling pathway therein. The results showed that C.pn increased the expression of LOX-1 in HUVECs in a dose- and time-dependent manner. C.pn-induced up-regulation of LOX-1 was mediated by ERK1/2, whereas p38 MAPK and JNK had no effect on this process. C.pn induced apoptosis, inhibited cell proliferation, and decreased the expression PPARγ in HUVECs. Additionally, LOX-1 activity and cell injury caused by C.pn through activation of ERK1/2 was completely inhibited by rosiglitazone, a PPARγ agonist. In conclusion, we inferred that activation of PPARγ in HUVECs suppressed C.pn-induced LOX-1 expression and cell damage by inhibiting ERK1/2 signaling.


Subject(s)
Atherosclerosis/genetics , Cardiovascular Diseases/genetics , PPAR gamma/genetics , Scavenger Receptors, Class E/genetics , Apoptosis/genetics , Atherosclerosis/microbiology , Atherosclerosis/pathology , Cardiovascular Diseases/microbiology , Cardiovascular Diseases/pathology , Cell Proliferation/genetics , Chlamydophila pneumoniae/genetics , Chlamydophila pneumoniae/pathogenicity , Gene Expression Regulation/genetics , Human Umbilical Vein Endothelial Cells/microbiology , Humans , MAP Kinase Signaling System/genetics , PPAR gamma/agonists , Rosiglitazone/pharmacology , Signal Transduction/drug effects , Umbilical Veins/metabolism , Umbilical Veins/pathology , p38 Mitogen-Activated Protein Kinases/genetics
13.
Microb Pathog ; 141: 103993, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31988008

ABSTRACT

Yersinia pestis, a Gram-negative bacterium, is the etiologic agent of plague. A hallmark of Y. pestis infection is the organism's ability to rapidly disseminate through an animal host. Y. pestis expresses the outer membrane protein, Ail (Attachment invasion locus), which is associated with host invasion and serum resistance. However, whether Ail plays a role in host dissemination remains unclear. In this study, C57BL/6J mice were challenged with a defined Y. pestis strain, KimD27, or an isogenic ail-deleted mutant derived from KimD27 via metacarpal paw pad inoculation, nasal drops, orogastric infection, or tail vein injection to mimic bubonic, pneumonic, oral, or septicemic plague, respectively. Our results showed that ail-deleted Y. pestis KimD27 lost the ability to invade host cells, leading to failed host dissemination in the pneumonic and oral plague models but not in the bubonic or septicemic plague models, which do not require invasiveness. Therefore, this study demonstrated that whether Ail plays a role in Y. pestis pathogenesis depends on the infection route.


Subject(s)
Bacterial Outer Membrane Proteins/metabolism , Plague/microbiology , Virulence Factors/metabolism , Virulence , Yersinia pestis , Animals , Bacterial Proteins/metabolism , Disease Models, Animal , Lung/microbiology , Mice , Mice, Inbred C57BL , Mouth/microbiology , Yersinia pestis/metabolism , Yersinia pestis/pathogenicity
14.
JBI Database System Rev Implement Rep ; 17(5): 985-1002, 2019 05.
Article in English | MEDLINE | ID: mdl-31090653

ABSTRACT

INTRODUCTION: Asthma is one of the most common diseases in children. A self-management program can effectively improve the outcomes for children with asthma and reduce the burden on healthcare services. OBJECTIVES: The aim of this project was to integrate the best evidence on asthma self-management with practice in a children's respiratory clinic and to improve compliance with best practice. METHODS: Seven audit criteria were developed for the pre- and post-audit based on the best available evidence. The Joanna Briggs Institute (JBI) Practical Application of Clinical Evidence System and Getting Research into Practice audit and feedback tools were used in this project. RESULTS: The baseline audit showed a gap between clinical practice and the best evidence. The only criterion that achieved high compliance was provision of inhaler guidance (100%). After implementation, there were substantial improvements in compliance for many criteria. Training of clinicians increased from 13% at baseline to 67% at follow-up. Education of parents improved, with specific education about asthma triggers increasing from 55% to 100%, education about warning signs from 30% to 85% and education about effective asthma treatment options from 40% to 85%. Use of written asthma action plans increased from 0% to 25%. CONCLUSION: Strategies developed in this project were effective at providing necessary information for parents and improved the compliance with evidence. Further implementation strategies and audits are still needed to improve the use of asthma action plans and ensure they are reviewed periodically.


Subject(s)
Asthma/therapy , Evidence-Based Practice , Health Personnel/education , Parents/education , Self-Management , Child , Health Knowledge, Attitudes, Practice , Hospitalization , Humans , Monitoring, Physiologic , Nebulizers and Vaporizers
15.
Infect Immun ; 87(8)2019 08.
Article in English | MEDLINE | ID: mdl-31085704

ABSTRACT

Salmonella enterica serovar Typhimurium, a Gram-negative bacterium, can cause infectious diseases ranging from gastroenteritis to systemic dissemination and infection. However, the molecular mechanisms underlying this bacterial dissemination have yet to be elucidated. A study indicated that using the lipopolysaccharide (LPS) core as a ligand, S Typhimurium was able to bind human dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (hCD209a), an HIV receptor that promotes viral dissemination by hijacking antigen-presenting cells (APCs). In this study, we showed that S Typhimurium interacted with CD209s, leading to the invasion of APCs and potentially the dissemination to regional lymph nodes, spleen, and liver in mice. Shielding of the exposed LPS core through the expression of O-antigen reduces dissemination and infection. Thus, we propose that similar to HIV, S Typhimurium may also utilize APCs via interactions with CD209s as a way to disseminate to the lymph nodes, spleen, and liver to initiate host infection.


Subject(s)
Cell Adhesion Molecules/physiology , Lectins, C-Type/physiology , Receptors, Cell Surface/physiology , Salmonella typhimurium/pathogenicity , Animals , Antigen-Presenting Cells/microbiology , Female , Host-Pathogen Interactions , Humans , Lipopolysaccharides/physiology , Mannans/pharmacology , Mice , Mice, Inbred C57BL , O Antigens/physiology , Peyer's Patches/physiology , Phagocytosis , RAW 264.7 Cells
16.
Front Immunol ; 10: 96, 2019.
Article in English | MEDLINE | ID: mdl-30915064

ABSTRACT

Yersinia pestis, a Gram-negative bacterium and the etiologic agent of plague, has evolved from Yersinia pseudotuberculosis, a cause of a mild enteric disease. However, the molecular and biological mechanisms of how Y. pseudotuberculosis evolved to such a remarkably virulent pathogen, Y. pestis, are not clear. The ability to initiate a rapid bacterial dissemination is a characteristic hallmark of Y. pestis infection. A distinguishing characteristic between the two Yersinia species is that Y. pseudotuberculosis strains possess an O-antigen of lipopolysaccharide (LPS) while Y. pestis has lost the O-antigen during evolution and therefore exposes its core LPS. In this study, we showed that Y. pestis utilizes its core LPS to interact with SIGNR1 (CD209b), a C-type lectin receptor on antigen presenting cells (APCs), leading to bacterial dissemination to lymph nodes, spleen and liver, and the initiation of a systemic infection. We therefore propose that the loss of O-antigen represents a critical step in the evolution of Y. pseudotuberculosis into Y. pestis in terms of hijacking APCs, promoting bacterial dissemination and causing the plague.


Subject(s)
Cell Adhesion Molecules/immunology , Host-Pathogen Interactions/immunology , Lectins, C-Type/immunology , Lipopolysaccharides/immunology , Plague/immunology , Receptors, Cell Surface/immunology , Yersinia pestis/physiology , Animals , Antigen-Presenting Cells/immunology , Cell Adhesion Molecules/genetics , Cell Line , Female , HeLa Cells , Humans , Lectins, C-Type/genetics , Macrophages/immunology , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Receptors, Cell Surface/genetics , Yersinia pseudotuberculosis/physiology , Yersinia pseudotuberculosis Infections/immunology
17.
Infect Immun ; 87(1)2019 01.
Article in English | MEDLINE | ID: mdl-30348825

ABSTRACT

Yersinia pseudotuberculosis is a Gram-negative enteropathogen and causes gastrointestinal infections. It disseminates from gut to mesenteric lymph nodes (MLNs), spleen, and liver of infected humans and animals. Although the molecular mechanisms for dissemination and infection are unclear, many Gram-negative enteropathogens presumably invade the small intestine via Peyer's patches to initiate dissemination. In this study, we demonstrate that Y. pseudotuberculosis utilizes its lipopolysaccharide (LPS) core to interact with CD209 receptors, leading to invasion of human dendritic cells (DCs) and murine macrophages. These Y. pseudotuberculosis-CD209 interactions result in bacterial dissemination to MLNs, spleens, and livers of both wild-type and Peyer's patch-deficient mice. The blocking of the Y. pseudotuberculosis-CD209 interactions by expression of O-antigen and with oligosaccharides reduces infectivity. Based on the well-documented studies in which HIV-CD209 interaction leads to viral dissemination, we therefore propose an infection route for Y. pseudotuberculosis where this pathogen, after penetrating the intestinal mucosal membrane, hijacks the Y. pseudotuberculosis-CD209 interaction antigen-presenting cells to reach their target destinations, MLNs, spleens, and livers.


Subject(s)
Cell Adhesion Molecules/metabolism , Dendritic Cells/microbiology , Endocytosis , Host-Pathogen Interactions , Lectins, C-Type/metabolism , Lipopolysaccharides/metabolism , Macrophages/microbiology , Receptors, Cell Surface/metabolism , Yersinia pseudotuberculosis/pathogenicity , Animals , Bacterial Adhesion , Cells, Cultured , Disease Models, Animal , Humans , Mice, Inbred BALB C , Mice, Inbred C57BL , Protein Binding , Yersinia Infections/microbiology , Yersinia Infections/pathology , Yersinia Infections/physiopathology
18.
Article in English | MEDLINE | ID: mdl-31998663

ABSTRACT

Uropathogenic Escherichia coli (UPEC), a Gram-negative bacterial pathogen, is a major causative agent of urinary tract infections (UTIs). However, the molecular mechanisms of how UPEC causes infections have not been determined. Recent studies indicated that certain enteric Gram-negative bacteria interact with and hijack innate immune receptors DC-SIGN (CD209a) and SIGNR1 (CD209b), often expressed by antigen-presenting cells (APCs), such as macrophages, leading to dissemination and infection. It was not known whether UPEC could utilize DC-SIGN receptors to promote its infection and dissemination similarly to the enteric pathogens. The results of this study reveal that UPEC interacts with CD209-expressing macrophages and transfectants. This interaction is inhibited by anti-CD209 antibody, indicating that CD209s are receptors for UPEC. Additionally, in contrast to the results of previous studies, mice lacking SIGNR1 are more susceptible to infection of this uropathogen, leading to prolonged bacterial persistence. Overall, the results of our study indicate that the innate immune receptor CD209s participate in the clearance of UPEC during UTIs.


Subject(s)
Escherichia coli Infections/immunology , Escherichia coli Infections/microbiology , Urinary Tract Infections/immunology , Urinary Tract Infections/microbiology , Uropathogenic Escherichia coli/immunology , Animals , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Cell Line , Disease Models, Animal , Escherichia coli Infections/pathology , Humans , Lectins, C-Type/genetics , Lectins, C-Type/metabolism , Macrophages/immunology , Macrophages/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Phagocytosis , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Urinary Tract/microbiology , Urinary Tract Infections/pathology , Uropathogenic Escherichia coli/pathogenicity
19.
Biol Pharm Bull ; 41(8): 1178-1185, 2018.
Article in English | MEDLINE | ID: mdl-30068867

ABSTRACT

Cardiorenal syndrome (CRS) is a frequently encountered clinical condition when the dysfunction of either the heart or kidneys amplifies the failure progression of the other organ. CRS remains a major global health problem. Qiliqiangxin (QLQX) is a traditional Chinese herbs medication, which can improve cardiac function, urine volume, and subjective symptoms in patients with chronic heart failure. In the present study, we aim to investigate the role of QLQX in the treatment of CRS type I and the possible mechanism through establishment of a rat model of myocardial infarction. Rats in CRS-Q group were orally treated with QLQX daily for 2 weeks or 4 weeks, while in sham group and CRS-C group were treated with saline at the same time. Enzyme-linked immunosorbent assay (ELISA) analysis showed that QLQX significantly reduced the levels of angiotensin II (AngII), brain natriuretic peptides (BNP), creatinine (CRE), cystatin C (CysC), tumor necrosis factor (TNF)-α, interleukin (IL)-6, microalbuminuria (MAU), and neutrophil gelatinase-associated lipocalin (NGAL) in plasma induced by myocardial infarction. Western blot analysis showed that QLQX significantly reduced the expressions of AngII, non-phagocytic cell oxidase (NOX)2, and B-cell lymphoma (Bcl)2 associated X protein (Bax), and increased the expressions of Bcl2 and Angiotensin II Type 1 receptor (ATR) in the kidney as compared with the CRS-C group. Fluorescence microscopy showed that the content of reactive oxygen species (ROS) was significantly reduced in the kidney as compared with the CRS-C group. We also examined the apoptosis level in kidney by using terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining, and the result showed that QLQX significantly reduced the apoptosis level in kidney induced by myocardial infarction. Taken together, we suggest that QLQX may be a potentially effective drug for the treatment of CRS by regulating inflammatory/oxidative stress signaling.


Subject(s)
Anti-Inflammatory Agents , Antioxidants , Cardio-Renal Syndrome/drug therapy , Drugs, Chinese Herbal , Myocardial Infarction/drug therapy , Albuminuria/blood , Albuminuria/drug therapy , Albuminuria/metabolism , Angiotensin II/blood , Angiotensin II/metabolism , Animals , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Cardio-Renal Syndrome/blood , Cardio-Renal Syndrome/metabolism , Creatinine/blood , Cystatin C/blood , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Interleukin-6/blood , Kidney/drug effects , Kidney/metabolism , Male , Myocardial Infarction/blood , Myocardial Infarction/metabolism , NADPH Oxidase 2/metabolism , Natriuretic Peptide, Brain/blood , Oxidative Stress/drug effects , Phytotherapy , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Receptor, Angiotensin, Type 1/metabolism , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/blood
20.
J Huazhong Univ Sci Technolog Med Sci ; 36(3): 344-349, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27376801

ABSTRACT

Lipooligosacharide (LOS) of Neisseria gonorrhoeae (gonococci, GC) is involved in the interaction of GC with host cells. Deletion of the alpha-oligosaccharide (alpha-OS) moiety of LOS (lgtF mutant) significantly impairs invasion of GC into epithelial cell lines. GC opacity (Opa) proteins, such as OpaI, mediate phagocytosis and stimulate chemiluminescence responses in neutrophils in part through interaction with members of the carcinoembryonic antigen (CEA) family, which includes CEACAM3 (CD66d), a human neutrophil specific receptor for phagocytosis of bacteria. In the present work, we examined the effects of OpaI-expressing lgtF mutant on phagocytosis by HeLa-CEACAM3 cells and chemiluminescence responses in neutrophils. The results showed that lgtF mutant even expressing OpaI completely lost the ability to promote either phagocytosis mediated by CEACAM3 interaction in HeLa cells or chemiluminescence responses in neutrophils. These data indicated that Opa proteins in the lgtF mutant, which might result from the conformational change, cannot be functional.


Subject(s)
Antigens, Bacterial/chemistry , Carcinoembryonic Antigen/immunology , Lipopolysaccharides/chemistry , Neisseria gonorrhoeae/metabolism , Neutrophils/immunology , Antigens, Bacterial/genetics , Antigens, Bacterial/immunology , Antigens, Bacterial/metabolism , Carbohydrate Sequence , Carcinoembryonic Antigen/genetics , Gene Expression Regulation , HeLa Cells , Host-Pathogen Interactions , Humans , Lipopolysaccharides/immunology , Luminescent Measurements , Mutation , Neisseria gonorrhoeae/genetics , Neisseria gonorrhoeae/pathogenicity , Neutrophils/microbiology , Phagocytosis
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