1.Porphyromonas gingivalis bacteremia increases the permeability of the blood-brain barrier via the Mfsd2a/Caveolin-1 mediated transcytosis pathway.
Shuang LEI ; Jian LI ; Jingjun YU ; Fulong LI ; Yaping PAN ; Xu CHEN ; Chunliang MA ; Weidong ZHAO ; Xiaolin TANG
International Journal of Oral Science 2023;15(1):3-3
Bacteremia induced by periodontal infection is an important factor for periodontitis to threaten general health. P. gingivalis DNA/virulence factors have been found in the brain tissues from patients with Alzheimer's disease (AD). The blood-brain barrier (BBB) is essential for keeping toxic substances from entering brain tissues. However, the effect of P. gingivalis bacteremia on BBB permeability and its underlying mechanism remains unclear. In the present study, rats were injected by tail vein with P. gingivalis three times a week for eight weeks to induce bacteremia. An in vitro BBB model infected with P. gingivalis was also established. We found that the infiltration of Evans blue dye and Albumin protein deposition in the rat brain tissues were increased in the rat brain tissues with P. gingivalis bacteremia and P. gingivalis could pass through the in vitro BBB model. Caveolae were detected after P. gingivalis infection in BMECs both in vivo and in vitro. Caveolin-1 (Cav-1) expression was enhanced after P. gingivalis infection. Downregulation of Cav-1 rescued P. gingivalis-enhanced BMECs permeability. We further found P. gingivalis-gingipain could be colocalized with Cav-1 and the strong hydrogen bonding between Cav-1 and arg-specific-gingipain (RgpA) were detected. Moreover, P. gingivalis significantly inhibited the major facilitator superfamily domain containing 2a (Mfsd2a) expression. Mfsd2a overexpression reversed P. gingivalis-increased BMECs permeability and Cav-1 expression. These results revealed that Mfsd2a/Cav-1 mediated transcytosis is a key pathway governing BBB BMECs permeability induced by P. gingivalis, which may contribute to P. gingivalis/virulence factors entrance and the subsequent neurological impairments.
Animals
;
Rats
;
Bacteremia/metabolism*
;
Blood-Brain Barrier/microbiology*
;
Caveolin 1/metabolism*
;
Gingipain Cysteine Endopeptidases/metabolism*
;
Permeability
;
Porphyromonas gingivalis/pathogenicity*
;
Transcytosis
;
Virulence Factors/metabolism*
2.Application and Prospect of Nanopore Sequencing Technology in Etiological Diagnosis of Blood Stream Infection.
Wei GUO ; Shuai-Hua FAN ; Peng-Cheng DU ; Jun GUO
Acta Academiae Medicinae Sinicae 2023;45(2):317-321
Blood stream infection (BSI),a blood-borne disease caused by microorganisms such as bacteria,fungi,and viruses,can lead to bacteremia,sepsis,and infectious shock,posing a serious threat to human life and health.Identifying the pathogen is central to the precise treatment of BSI.Traditional blood culture is the gold standard for pathogen identification,while it has limitations in clinical practice due to the long time consumption,production of false negative results,etc.Nanopore sequencing,as a new generation of sequencing technology,can rapidly detect pathogens,drug resistance genes,and virulence genes for the optimization of clinical treatment.This paper reviews the current status of nanopore sequencing technology in the diagnosis of BSI.
Humans
;
Nanopore Sequencing
;
Sepsis/diagnosis*
;
Bacteremia/microbiology*
;
Bacteria
;
Blood Culture/methods*
3.Clinical factors associated with composition of lung microbiota and important taxa predicting clinical prognosis in patients with severe community-acquired pneumonia.
Sisi DU ; Xiaojing WU ; Binbin LI ; Yimin WANG ; Lianhan SHANG ; Xu HUANG ; Yudi XIA ; Donghao YU ; Naicong LU ; Zhibo LIU ; Chunlei WANG ; Xinmeng LIU ; Zhujia XIONG ; Xiaohui ZOU ; Binghuai LU ; Yingmei LIU ; Qingyuan ZHAN ; Bin CAO
Frontiers of Medicine 2022;16(3):389-402
Few studies have described the key features and prognostic roles of lung microbiota in patients with severe community-acquired pneumonia (SCAP). We prospectively enrolled consecutive SCAP patients admitted to ICU. Bronchoscopy was performed at bedside within 48 h of ICU admission, and 16S rRNA gene sequencing was applied to the collected bronchoalveolar lavage fluid. The primary outcome was clinical improvements defined as a decrease of 2 categories and above on a 7-category ordinal scale within 14 days following bronchoscopy. Sixty-seven patients were included. Multivariable permutational multivariate analysis of variance found that positive bacteria lab test results had the strongest independent association with lung microbiota (R2 = 0.033; P = 0.018), followed by acute kidney injury (AKI; R2 = 0.032; P = 0.011) and plasma MIP-1β level (R2 = 0.027; P = 0.044). Random forest identified that the families Prevotellaceae, Moraxellaceae, and Staphylococcaceae were the biomarkers related to the positive bacteria lab test results. Multivariable Cox regression showed that the increase in α-diversity and the abundance of the families Prevotellaceae and Actinomycetaceae were associated with clinical improvements. The positive bacteria lab test results, AKI, and plasma MIP-1β level were associated with patients' lung microbiota composition on ICU admission. The families Prevotellaceae and Actinomycetaceae on admission predicted clinical improvements.
Acute Kidney Injury/complications*
;
Bacteria/classification*
;
Chemokine CCL4/blood*
;
Community-Acquired Infections/microbiology*
;
Humans
;
Lung
;
Microbiota/genetics*
;
Pneumonia, Bacterial/diagnosis*
;
Prognosis
;
RNA, Ribosomal, 16S/genetics*
5.Correlation between Vitamin D Status and Gut Microbiota in Patients with Inflammatory Bowel Disease.
Dan CHEN ; Yue LI ; Han SUN ; Meng XIAO ; Rui Li ZHANG ; Ling QIU ; Bei TAN ; Jia Ming QIAN
Acta Academiae Medicinae Sinicae 2020;42(6):740-748
Objective To investigate the correlation between serum total 25-hydroxyvitamin D[T-25(OH)D]level and fecal microbiota in patients with inflammatory bowel disease(IBD). Methods Twenty-three patients with IBD completed the tests for serum T-25(OH)D,and the fecal microbiota was studied using V4 hypervariable region of 16S ribosomal RNA(rRNA)gene sequencing.According to serum T-25(OH)D level,the patients were divided into three groups including vitamin D normal group(
Bacteria/classification*
;
Feces/microbiology*
;
Gastrointestinal Microbiome
;
Humans
;
Inflammatory Bowel Diseases/microbiology*
;
RNA, Ribosomal, 16S/genetics*
;
Vitamin D/blood*
7.Quantification of Panax notoginseng saponins metabolites in rat plasma with in vivo gut microbiota-mediated biotransformation by HPLC-MS/MS.
Yin-Ping GUO ; Man-Yun CHEN ; Li SHAO ; Wei ZHANG ; Tai RAO ; Hong-Hao ZHOU ; Wei-Hua HUANG
Chinese Journal of Natural Medicines (English Ed.) 2019;17(3):231-240
Panax notoginseng saponins (PNS) are the major components of Panax notoginseng, with multiple pharmacological activities but poor oral bioavailability. PNS could be metabolized by gut microbiota in vitro, while the exact role of gut microbiota of PNS metabolism in vivo remains poorly understood. In this study, pseudo germ-free rat models were constructed by using broad-spectrum antibiotics to validate the gut microbiota-mediated transformation of PNS in vivo. Moreover, a high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) was developed for quantitative analysis of four metabolites of PNS, including ginsenoside F1 (GF1), ginsenoside Rh2 (GRh2), ginsenoside compound K (GCK) and protopanaxatriol (PPT). The results showed that the four metabolites could be detected in the control rat plasma, while they could not be determined in pseudo germ-free rat plasma. The results implied that PNS could not be biotransformed effectively when gut microbiota was disrupted. In conclusion, gut microbiota plays an important role in biotransformation of PNS into metabolites in vivo.
Animals
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Anti-Bacterial Agents
;
pharmacology
;
Biotransformation
;
Chromatography, High Pressure Liquid
;
Feces
;
microbiology
;
Gastrointestinal Microbiome
;
drug effects
;
physiology
;
Ginsenosides
;
blood
;
Male
;
Panax notoginseng
;
chemistry
;
Rats, Sprague-Dawley
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Sapogenins
;
blood
;
Saponins
;
administration & dosage
;
metabolism
;
Tandem Mass Spectrometry
8.Changes in peripheral blood inflammatory factors (TNF-α and IL-6) and intestinal flora in AIDS and HIV-positive individuals.
Jing LU ; Sai-Sai MA ; Wei-Ying ZHANG ; Jian-Ping DUAN
Journal of Zhejiang University. Science. B 2019;20(10):793-802
OBJECTIVE:
In this study, we investigated the changes in peripheral blood inflammatory factors and intestinal flora in acquired immune deficiency syndrome (AIDS) and human immunodeficiency virus (HIV)-positive individuals (AIDS/HIV patients), and explored the relationships among intestinal flora, peripheral blood inflammatory factors, and CD4+ T lymphocytes.
METHODS:
Thirty blood and stool samples from an AIDS group and a control group were collected. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were determined by enzyme-linked immunosorbent assay (ELISA), and the number of CD4+ T lymphocytes by a FACSCount automated instrument. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the messenger RNA (mRNA) levels of Bifidobacterium, Lactobacillus, Escherichia coli, Enterococcus faecalis, and Enterococcus faecium. Correlations among intestinal flora, inflammatory factor levels, and CD4+ T lymphocyte values were evaluated using the Spearman correlation coefficient.
RESULTS:
The levels of TNF-α and IL-6 in the AIDS group were higher than those in the control group, while the number of CD4+ T lymphocytes was lower. The amounts of Bifidobacterium and Lactobacillus in the AIDS group were significantly lower than those in control group, while the amounts of E. coli, E. faecalis, and E. faecium were much higher. The amounts of Bifidobacterium and Lactobacillus were negatively correlated with the content of TNF-α and IL-6 and the CD4+ T lymphocyte count, while those correlations were reversed for E. coli, E. faecalis, and E. faecium.
CONCLUSIONS
The intestinal microbiota of AIDS/HIV patients were disordered, and there was a correlation between the amount of intestinal flora and the number of CD4+ T lymphocytes and the levels of TNF-α and IL-6.
Acquired Immunodeficiency Syndrome/microbiology*
;
Adult
;
Aged
;
CD4 Lymphocyte Count
;
Female
;
Gastrointestinal Microbiome
;
HIV Infections/microbiology*
;
Humans
;
Interleukin-6/blood*
;
Male
;
Middle Aged
;
Tumor Necrosis Factor-alpha/blood*
9.Identification of poliumoside metabolites in rat plasma, urine, bile, and intestinal bacteria with UPLC/Q-TOF-MS.
Hao QIAN ; Fang-Jun YU ; Dan-Yi LU ; Bao-Jian WU ; Xing-Wang ZHANG ; Huan WANG ; Zhi-Guo MA
Chinese Journal of Natural Medicines (English Ed.) 2018;16(11):871-880
Poliumoside is representative of phenylethanoid glycosides, which are widely found in many plants. Poliumoside is also regarded as the main active component of Callicarpa kwangtungensis Chun (CK), though its oral bioavailability in rat is extremely low (0.69%) and its in vivo and in vitro metabolism has not yet been systematically investigated. In the present study, an ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF-MS) method was employed to identify the metabolites and investigate the metabolic pathways of poliumoside in rat after oral administration 1.5 g·kg of poliumoside. As a result, a total of 34 metabolites (30 from urine, 17 from plasma, and 4 from bile) and 9 possible metabolic pathways (rearrangment, reduction, hydration, hydrolyzation, dehydration, methylation, hydroxylation, acetylation, and sulfation) were proposed in vivo. The main metabolite, acteoside, was quantified after incubated with rat intestinal bacteria in vitro. In conclusion, the present study systematically explored the metabolites of poliumoside in vivo and in vitro, proposing metabolic pathways that may be significant for further metabolic studies of poliumoside.
Administration, Oral
;
Animals
;
Bacteria
;
metabolism
;
Bile
;
chemistry
;
Caffeic Acids
;
administration & dosage
;
blood
;
chemistry
;
urine
;
Callicarpa
;
chemistry
;
Chromatography, High Pressure Liquid
;
Drugs, Chinese Herbal
;
administration & dosage
;
chemistry
;
metabolism
;
Glycosides
;
administration & dosage
;
blood
;
chemistry
;
urine
;
Intestines
;
microbiology
;
Male
;
Mass Spectrometry
;
methods
;
Molecular Structure
;
Plasma
;
chemistry
;
Rats
;
Rats, Sprague-Dawley
;
Urine
;
chemistry
10.Cefoxitin plus levofloxacin for prevention of severe infection after transrectal prostate biopsy.
Rong-Bing LI ; Xiao-Fei WEN ; Yue-Min WANG ; Wei-Hua CHEN ; Xue-Lei WANG ; Ji-Ling WEN ; Lin-Jie SHEN
National Journal of Andrology 2018;24(4):322-326
ObjectiveTo evaluate the effect of cefoxitin prophylactic in reducing the incidence of severe infection after transrectal prostate biopsy (TRPB).
METHODSThis retrospective study included 155 cases of TRPB with a 5-day administration of oral levofloxacin at 200 mg bid (the control group) and another 167 cases with a 3-day administration of oral levofloxacin at the same dose plus intravenous cefoxitin at 2.0 g 2 hours before TRPB (the experimental group) according to the distribution characteristics of drug-resistance bacteria in our department. The patients of the control and experimental groups were aged (68.68 ± 8.12) and (68.72 ± 7.51) years, with PSA levels of (19.78 ± 21.57) and (21.15 ± 42.63) μg/L, involving (11.68 ± 1.44) and (11.77±1.02) biopsy cores, respectively. Comparisons were made between the two groups of patients in the incidence rate of severe infection, which was defined as lower urinary track symptoms plus the systemic inflammatory response syndrome (SIRS) within 7 days after TRPB.
RESULTSThe incidence rate of postoperative severe infection was significantly lower in the experimental group than in the control (0.6% [1/167] vs 5.8% [9/155], P < 0.05). Blood cultures revealed positive E-coli strains in 6 cases in the control group, including 5 ESBL-positive and 4 quinolone-resistant and amikacin-sensitive cases, all sensitive to cefoxitin, cefoperazone/sulbactam and imipenem. The only one case of severe infection was shown to be negative in blood culture.
CONCLUSIONSPreoperative intravenous administration of cefoxitin according to the specific distribution characteristics of drug-resistance bacteria can significantly reduce the incidence of severe infection after TRPB.
Aged ; Anti-Bacterial Agents ; therapeutic use ; Biopsy ; adverse effects ; methods ; Cefoxitin ; therapeutic use ; Drug Resistance, Bacterial ; Escherichia coli ; isolation & purification ; Escherichia coli Infections ; microbiology ; prevention & control ; Humans ; Levofloxacin ; therapeutic use ; Male ; Middle Aged ; Postoperative Complications ; blood ; prevention & control ; Prostate ; pathology ; Retrospective Studies

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