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1.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(7): 768-773, 2024 Jul.
Article de Chinois | MEDLINE | ID: mdl-39223895

RÉSUMÉ

Sepsis is a common and severe infectious disease, and its associated coagulation dysfunction can cause disseminated intravascular coagulation (DIC) and organ failure, leading to a significant increase in mortality. Pyroptosis is a form of programmed cell death mediated by caspase-1 in the classical pathway and caspase-4/caspase-5/caspase-11 in the non-classical pathway, along with the effector molecule gasdermin (GSDM) family. Recent studies have shown that pyroptosis plays an important role in the development of coagulation disorders in sepsis. Pyroptosis leads to the formation of cytoplasmic membrane pores, cell swelling and membrane rupture, as well as the release and enhanced activity of procoagulant contents, strongly promoting the development of systemic coagulation activation and DIC in sepsis. Therefore, exploring the role and molecular mechanisms of pyroptosis in sepsis-related coagulation disorders is of great significance for the prevention and treatment of sepsis. This article provides a review of the mechanisms involved in pyroptosis and coagulation disorders in sepsis, as well as the role and mechanisms of pyroptosis in sepsis-associated coagulation disorders to provide new ideas for sepsis related research.


Sujet(s)
Troubles de l'hémostase et de la coagulation , Coagulation intravasculaire disséminée , Pyroptose , Sepsie , Sepsie/métabolisme , Sepsie/complications , Sepsie/physiopathologie , Humains , Troubles de l'hémostase et de la coagulation/étiologie , Coagulation intravasculaire disséminée/étiologie , Caspases/métabolisme , Caspase-1/métabolisme , Animaux
2.
Cell Stem Cell ; 29(11): 1562-1579.e7, 2022 11 03.
Article de Anglais | MEDLINE | ID: mdl-36332570

RÉSUMÉ

During fetal development, human hematopoietic stem cells (HSCs) colonize the bone marrow (BM), where they self-renew and sustain hematopoiesis throughout life; however, the precise timepoint at which HSCs seed the BM is unclear. We used single-cell RNA-sequencing to map the transcriptomic landscape of human fetal BM and spleen hematopoietic stem/progenitor cells (HSPCs) and their microenvironment from 10 to 14 post-conception weeks (PCWs). We further demonstrated that functional HSCs capable of reconstituting long-term multi-lineage hematopoiesis in adult NOG mice do not emerge in the BM until 12 PCWs. In contrast, functional HSCs were not detected in the spleen by 14 PCWs. By comparing the niche-HSPC interactions between BM and spleen, we identified ligand-receptor pairs likely to be involved in fetal HSC migration and maintenance. Our work paves the way for research into the mechanisms underlying HSC colonization in human fetal BM and provides invaluable resources for future studies on HSC development.


Sujet(s)
Moelle osseuse , Cellules souches hématopoïétiques , Adulte , Humains , Souris , Animaux , Hématopoïèse/génétique , Cellules de la moelle osseuse , Analyse de séquence d'ARN
3.
Arterioscler Thromb Vasc Biol ; 41(12): 2877-2889, 2021 12.
Article de Anglais | MEDLINE | ID: mdl-34645279

RÉSUMÉ

OBJECTIVE: METTL3 (methyltransferase-like protein 3)-mediated N6-methyladenosine modification is the most abundant RNA modification on eukaryote mRNAs and plays a crucial role in diverse physiological and pathological processes. However, whether N6-methyladenosine modification has function in thrombosis is unknown. This study aims to determine the role of METTL3 in the endothelial cells-mediated thrombosis. Approach and Results: RNA-sequencing and real-time quantitative PCR revealed that the expression of PAI-1 (plasminogen activator inhibitor-1) was downregulated in METTL3 knockdown human umbilical vein endothelial cells. In vitro experiments showed that METTL3 suppressed fibrinolysis. Mechanically, RNA methylation sequencing and meRIP-quantitative real-time PCR showed that METTL3 catalyzed N6-methyladenosine modification on 3' UTR of JUN mRNA. Western blotting analysis showed that METTL3 promoted JUN protein expression. Chromatin immunoprecipitation analysis demonstrated that JUN bound to the PAI-1 promoter in human umbilical vein endothelial cells. Furthermore, mice challenged with lipopolysaccharide resulted in higher METTL3 expression in vessels. Endothelial-specific knockdown of Mettl3 decreased expression of active PAI-1 in plasma and attenuated fibrin deposition in livers and lungs during endotoxemia. CONCLUSIONS: Our study reveals that METTL3-mediated N6-methyladenosine modification plays a crucial role in fibrinolysis and is an underlying target for the therapy of thrombotic disorders.


Sujet(s)
Endothélium vasculaire/métabolisme , Fibrinolyse , Methyltransferases/métabolisme , Inhibiteur-1 d'activateur du plasminogène/métabolisme , Protéines de liaison à l'ARN/métabolisme , Thrombose/métabolisme , Régions 3' non traduites , Animaux , Régulation négative , Gènes jun , Cellules endothéliales de la veine ombilicale humaine/métabolisme , Humains , Souris de lignée C57BL , ARN messager/métabolisme , Réaction de polymérisation en chaine en temps réel , Analyse de séquence d'ARN , Régulation positive
4.
Cell Res ; 31(10): 1106-1122, 2021 10.
Article de Anglais | MEDLINE | ID: mdl-34239074

RÉSUMÉ

Whereas the critical roles of innate lymphoid cells (ILCs) in adult are increasingly appreciated, their developmental hierarchy in early human fetus remains largely elusive. In this study, we sorted human hematopoietic stem/progenitor cells, lymphoid progenitors, putative ILC progenitor/precursors and mature ILCs in the fetal hematopoietic, lymphoid and non-lymphoid tissues, from 8 to 12 post-conception weeks, for single-cell RNA-sequencing, followed by computational analysis and functional validation at bulk and single-cell levels. We delineated the early phase of ILC lineage commitment from hematopoietic stem/progenitor cells, which mainly occurred in fetal liver and intestine. We further unveiled interleukin-3 receptor as a surface marker for the lymphoid progenitors in fetal liver with T, B, ILC and myeloid potentials, while IL-3RA- lymphoid progenitors were predominantly B-lineage committed. Notably, we determined the heterogeneity and tissue distribution of each ILC subpopulation, revealing the proliferating characteristics shared by the precursors of each ILC subtype. Additionally, a novel unconventional ILC2 subpopulation (CRTH2- CCR9+ ILC2) was identified in fetal thymus. Taken together, our study illuminates the precise cellular and molecular features underlying the stepwise formation of human fetal ILC hierarchy with remarkable spatiotemporal heterogeneity.


Sujet(s)
Immunité innée , Lymphocytes , Différenciation cellulaire , Foetus , Cellules souches hématopoïétiques , Humains
5.
EClinicalMedicine ; 36: 100894, 2021 Jun.
Article de Anglais | MEDLINE | ID: mdl-34041460

RÉSUMÉ

BACKGROUND: Preoperative anemia is an important pillar of perioperative patient blood management. However, there was no literature comprehensively described the current situation of preoperative anemia in China. METHODS: We conducted a national retrospective cross-sectional study to assess the prevalence and intervention of preoperative anemia in Chinese adults. Data were from the National Preoperative Anemia Database based on hospital administration data from January 1, 2013 to December 31, 2018. FINDINGS: A total of 797,002 patients were included for analysis. Overall, 27.57% (95% CI 27.47-27.67) of patients had preoperative anemia, which varied by gender, age, regions, and type of operation. Patients who were female, age over 60 years old, from South China, from provinces with lower per capita GDP, underwent operations on the lymphatic and hematopoietic system, with laboratory abnormalities were more likely to have a high risk of preoperative anemia. Among patients with preoperative anemia, 5.16% (95% CI 5.07-5.26) received red blood cell transfusion, 7.79% (95% CI 7.67-7.91) received anemia-related medications such as iron, erythropoietin, folic acid or vitamin B12, and 12.25% (95% CI 12.10-12.40) received anemia-related therapy (red blood cell transfusion or anemia-related medications) before operation. The probability of preoperative RBC transfusion decreased by 54.92% (OR 0.46, 95% CI 0.46-0.47) as each 10-g/L increase in preoperative hemoglobin. Patients with preoperative hemoglobin less than 130 g/L was associated with longer hospital stay and more hospital costs. Patients with severe preoperative anemia given iron preoperatively had lower intra/post-operative RBC transfusion rate, shorter length of stay and less hospitalization costs, but no similar correlation was found in patients with mild and moderate preoperative anemia and patients given erythropoietin preoperatively. INTERPRETATION: Our present study shows that preoperative anemia is currently a relatively prevalent problem that has not been fully appreciated in China. More researches will be required to optimize the treatment of preoperative anemia. FUNDING: National Natural Science Foundation of China and the Logistics Support Department of the Central Military Commission.

6.
Mil Med Res ; 7(1): 15, 2020 04 03.
Article de Anglais | MEDLINE | ID: mdl-32241296

RÉSUMÉ

Thrombocytopenia is a common complication of critical care patients. The rates of bleeding events and mortality are also significantly increased in critical care patients with thrombocytopenia. Therefore, the Critical Care Medicine Committee of Chinese People's Liberation Army (PLA) worked with Chinese Society of Laboratory Medicine, Chinese Medical Association to develop this consensus to provide guidance for clinical practice. The consensus includes five sections and 27 items: the definition of thrombocytopenia, etiology and pathophysiology, diagnosis and differential diagnosis, treatment and prevention.


Sujet(s)
Thrombopénie/diagnostic , Thrombopénie/thérapie , Chine/épidémiologie , Consensus , Soins de réanimation/méthodes , Soins de réanimation/tendances , Diagnostic différentiel , Humains , Thrombopénie/physiopathologie
7.
Transfusion ; 59(1): 196-206, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-30499593

RÉSUMÉ

BACKGROUND: The pathomechanisms of complications due to blood transfusion are not fully understood. Elevated levels of heme derived from stored RBCs are thought to be associated with transfusion reactions, especially inflammatory responses. Recently, the proinflammatory effect of heme has been widely studied. However, it is still unknown whether heme can influence the resolution of inflammation, a key step of inflammatory response. STUDY DESIGN AND METHODS: A murine model of self-limited peritonitis was used, and resolution was assessed by resolution indices. Western blot, quantitative reverse transcriptase polymerase chain reaction, chemotaxis assay, luciferase reporter assay, and lentivirus infections were used to investigate possible mediating mechanisms in neutrophils. RESULTS: The administration of hemin by intraperitoneal injection significantly increased the leukocyte infiltration and prolonged the resolution interval by approximately 7 hours in mouse peritonitis. In vitro, hemin significantly downregulated ALX/FPR2 protein levels (p < 0.05), a key resolution receptor, leading to the suppression of proresolution responses triggered by the proresolution ligand resolvin D1. Subsequently, miR-144-3p, selected by prediction databases, was found to be significantly upregulated by hemin (p < 0.05). The inhibition of miR-144-3p attenuated the inhibitory effect of hemin on lipoxin A4 receptor (ALX)/formyl peptide receptor 2 (FPR2) protein expression (p < 0.05). Luciferase reporter assay confirmed that miR-144-3p directly bound ALX/FPR2 3'-UTR. MiR-144-3p overexpression significantly downregulated ALX/FPR2 protein levels, whereas miR-144-3p inhibition led to a significant increase in ALX/FPR2 (p < 0.05). CONCLUSION: Our results suggest that hemin prolongs resolution in self-limited inflammation, and this action is associated with downregulation of ALX/FPR2 mediated by hemin-induced miR-144-3p. These findings demonstrate a novel mechanism of hemin derived from stored RBCs for inflammatory response.


Sujet(s)
Hémine/usage thérapeutique , Inflammation/génétique , microARN/métabolisme , Régions 3' non traduites/génétique , Animaux , Technique de Western , Cellules cultivées , Test ELISA , Érythrocytes/effets des médicaments et des substances chimiques , Cytométrie en flux , Cellules HL-60 , Hème/génétique , Hème/métabolisme , Humains , Inflammation/traitement médicamenteux , Mâle , Souris , Souris de lignée C57BL , microARN/génétique , Granulocytes neutrophiles/effets des médicaments et des substances chimiques , Granulocytes neutrophiles/métabolisme , Réaction de polymérisation en chaine en temps réel , Transduction du signal/effets des médicaments et des substances chimiques , Transduction du signal/génétique
8.
J Intensive Care Med ; 33(5): 296-309, 2018 May.
Article de Anglais | MEDLINE | ID: mdl-27756870

RÉSUMÉ

INTRODUCTION: The Surviving Sepsis Campaign guidelines recommend early goal-directed therapy (EGDT) for the resuscitation of patients with sepsis; however, the recent evidences quickly evolve and convey conflicting results. We performed a meta-analysis to evaluate the effect of EGDT on mortality in adults with severe sepsis and septic shock. METHODS: We searched electronic databases to identify randomized controlled trials that compared EGDT with usual care or lactate-guided therapy in adults with severe sepsis and septic shock. Predefined primary outcome was all-cause mortality at final follow-up. RESULTS: We included 13 trials enrolling 5268 patients. Compared with usual care, EGDT was associated with decreased mortality (risk ratio [RR]: 0.87, 95% CI: 0.77-0.98; 4664 patients, 8 trials; Grading of Recommendations Assessment, Development, and Evaluation [GRADE] quality of evidence was moderate). Compared with lactate clearance-guided therapy, EGDT was associated with increased mortality (RR: 1.60, 95% CI: 1.24-2.06; 604 patients, 5 trials; GRADE quality of evidence was low). Patients assigned to EGDT received more intravenous fluid, red cell transfusion, vasopressor infusion, and dobutamine use within the first 6 hours than those assigned to usual care (all P values < .00001). CONCLUSION: Adults with severe sepsis and septic shock who received EGDT had a lower mortality than those given usual care, the benefit may mainly be attributed to treatments administered within the first 6 hours. However, the underlying mechanisms by which lactate clearance-guided therapy benefits these patients are yet to be investigated.


Sujet(s)
Traitement précoce ciblé/statistiques et données numériques , Mortalité hospitalière , Réanimation/mortalité , Sepsie/mortalité , Sepsie/thérapie , Choc septique/mortalité , Choc septique/thérapie , Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Essais contrôlés randomisés comme sujet , Réanimation/méthodes , Facteurs temps , Délai jusqu'au traitement/statistiques et données numériques , Résultat thérapeutique
9.
Crit Care ; 21(1): 171, 2017 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-28679406

RÉSUMÉ

BACKGROUND: Formyl peptide receptor 2-lipoxin receptor (FPR2/ALX) modulates the anti-inflammatory response and therefore may be a target for treating sepsis. The purpose of this study was to investigate the association between genetic variants of the FPR2/ALX gene and sepsis after severe trauma as well as to further analyze the functions of sepsis-related genetic polymorphisms. METHODS: Three tag single-nucleotide polymorphisms (tag SNPs) that captured all common alleles across the FPR2/ALX genomic region were genotyped using pyrosequencing in an initial sample consisting of 275 patients with severe trauma. The rs11666254 polymorphism, which had statistical significance, was genotyped in an additional 371 patients, and logistic regression analysis was performed to determine associations between the FPR2/ALX gene polymorphism and sepsis susceptibility after severe trauma. The messenger RNA (mRNA) and protein levels of FPR2/ALX in the lipopolysaccharide-stimulated white blood cells of trauma patients were determined by performing quantitative polymerase chain reactions and Western blot analysis. Tumor necrosis factor (TNF)-α production was measured by enzyme-linked immunosorbent assay. The effects of the promoter polymorphism rs11666254 on the transcription activity of FPR2/ALX were analyzed using a luciferase reporter assay. RESULTS: Among the three tag SNPs, only the rs11666254 polymorphism was found to be significantly associated with sepsis in trauma patients, and this association persisted after a pooled analysis of all 646 trauma patients, which showed that patients who carried the A allele of rs11666254 had a significantly higher risk of developing sepsis than individuals who carried the G allele. This SNP was also significantly associated with lower FPR2/ALX mRNA and protein expression as well as higher TNF-α production from the peripheral blood leukocyte response to bacterial lipoprotein stimulation. In addition, the rs11666254 polymorphism could significantly decrease the promoter activity of the FPR2/ALX gene. CONCLUSIONS: The rs11666254 polymorphism in the FPR2/ALX gene is a functional SNP that increases sepsis susceptibility in patients after traumatic injury.


Sujet(s)
Protéines adaptatrices de la transduction du signal/génétique , Récepteurs aux peptides formylés/génétique , Récepteurs de la lipoxine/génétique , Sepsie/génétique , Plaies et blessures/génétique , Protéines adaptatrices de la transduction du signal/pharmacologie , Protéines adaptatrices de la transduction du signal/usage thérapeutique , Adolescent , Adulte , Sujet âgé , Chine , Femelle , Cytométrie en flux/méthodes , Humains , Score de gravité des lésions traumatiques , Mâle , Adulte d'âge moyen , Polymorphisme de nucléotide simple/physiologie , Sepsie/métabolisme , Plaies et blessures/métabolisme
10.
Transfus Med Rev ; 31(2): 107-112, 2017 04.
Article de Anglais | MEDLINE | ID: mdl-28063764

RÉSUMÉ

Patients with cirrhosis used to be associated with frequent use of blood components because of their complex disorder of hemostasis and bleeding complications. Recent findings have indicated that patients with cirrhosis have a state of "rebalanced" or even procoagulant hemostasis and have questioned the prophylactic use of plasma. To evaluate the current status of plasma use in patients with cirrhosis, we conducted a retrospective survey in 11 tertiary-care hospitals in China from September 1 to October 31, 2013. All patients admitted with cirrhosis during the study period were included in the study. The survey collected information including patients' diagnostic and demographic data, clinical course including bleeding complications and invasive procedures, laboratory results, and plasma transfusion data. Among 1595 patients with cirrhosis admitted to the 11 hospitals, 236 (14.8%) patients received 1 or more plasma transfusions during the study period. The number of plasma transfusions is defined as the number of transfusion orders. A total of 1037 plasma transfusions were administered to these patients, with a mean of 4.4 transfusions per transfused patient, ranging from 1 to 22 transfusions per transfused patient. Most plasma transfusions (760/1037; 73.3%) were given to patients without bleeding, for treatment of coagulopathy either without planned invasive procedures (70.4%) or before invasive procedures (2.9%). The median dose of plasma transfusion was 3.8 mL/kg. The rate of plasma transfusion of participating hospitals varied from 5.3% to 31.8%. It is encouraging to see that in one teaching hospital, 85.7% plasma transfusions were given to patients with bleeding indication, showing a promising sign in appropriate transfusion. Prophylaxis or empirical plasma transfusion is still a common problem in managing patients with liver cirrhosis. Wide variations are found in plasma transfusion practice among hospitals. Effective measures to control and reduce empirical correction of abnormal coagulation tests through transfusing plasma should be strengthened urgently.


Sujet(s)
Troubles de l'hémostase et de la coagulation/thérapie , Transfusion de composants du sang , Cirrhose du foie/thérapie , Adulte , Troubles de l'hémostase et de la coagulation/complications , Troubles de l'hémostase et de la coagulation/épidémiologie , Transfusion de composants du sang/statistiques et données numériques , Chine/épidémiologie , Comorbidité , Femelle , Humains , Cirrhose du foie/complications , Cirrhose du foie/épidémiologie , Mâle , Adulte d'âge moyen , Études rétrospectives , Centres de soins tertiaires/statistiques et données numériques
11.
Dig Liver Dis ; 48(12): 1478-1484, 2016 Dec.
Article de Anglais | MEDLINE | ID: mdl-27665260

RÉSUMÉ

BACKGROUND: Cirrhosis is a complex acquired disorder of hemostasis and patients frequently receive blood transfusions. But there is very limited data on patterns of blood use at a patient level. AIMS: To characterize blood use in cirrhotic patients in China and compare with recommendations to help identify areas where quality improvement strategies can be targeted. We also compared findings to a similar study undertaken in UK. METHODS: A cross-sectional study was conducted in 11 hospitals over a 2-month period. Data were collected prospectively on each hospitalized cirrhotic patient to day 28. RESULTS: 1595 cirrhotic patients were included and 20.6% were transfused. 48.2% of transfused patients received transfusion for bleeding, most commonly gastrointestinal bleeding (65.8%). The remaining 51.8% were transfused for non-bleeding indications. 32.5% of patients transfused for gastrointestinal bleeding with red blood cells had a pre-transfusion haemoglobin >7g/dL. 89.1% of patients transfused frozen plasma for non-bleeding indications received them in the absence of a planned procedure. The patterns of blood transfusion in cirrhosis were different between China and UK. Of note, empirical prophylactic use of frozen plasma was more common in the Chinese study (89%) than in the UK (24%). CONCLUSION: Education and research should be implemented to improve patient blood management, especially in prophylactic frozen plasma use area.


Sujet(s)
Transfusion de composants du sang/statistiques et données numériques , Hémorragie gastro-intestinale/thérapie , Cirrhose du foie/complications , Adulte , Sujet âgé , Chine , Études transversales , Femelle , Hémoglobines/analyse , Humains , Durée du séjour , Cirrhose du foie/étiologie , Mâle , Adulte d'âge moyen , Plasma sanguin , Études prospectives , Amélioration de la qualité , Royaume-Uni
12.
J Surg Res ; 200(2): 619-30, 2016 Feb.
Article de Anglais | MEDLINE | ID: mdl-26432471

RÉSUMÉ

BACKGROUND: BML-111 is a lipoxin receptor agonist that has protective effects in various lung injury models. We tried to elucidate whether BML-111 could mitigate lung injury in a mouse model of endotoxemia and endothelial hyperpermeability in vitro. METHODS: The effect of BML-111 on lung injury was evaluated using C57BL/6 mice and human umbilical vein endothelial cells (HUVECs). Male C57BL/6 mice were intraperitoneally injected with normal saline, BML-111, and/or the lipoxin receptor antagonist Boc-2. Then, either lipopolysaccharide (LPS) or normal saline was given intraperitoneally. Lung injury was assessed by a pathohistologic examination for neutrophil infiltration, pulmonary endothelial permeability, and inflammatory cytokines in lung tissue and bronchoalveolar lavage fluid. HUVECs were treated with or without BML-111 before incubation with LPS for 24 h. Boc-2 was also tested as a novel inhibitor of BML-111. A Transwell assay was used to evaluate the permeability of HUVECs. Junction protein expression was also assessed. RESULTS: BML-111 significantly improved the mouse survival rate, reduced body weight loss, attenuated the pulmonary pathologic changes, inhibited neutrophil infiltration and proinflammatory cytokine production, and mitigated endothelial hyperpermeability. The decreased expression of junction proteins induced by LPS in lung tissue and endothelial cells were upregulated by BML-111. In addition, BML-111 inhibited the activation of the Akt, ERK1/2, and p38 MAPK signaling pathways. However, the beneficial effects of BML-111 were abolished by Boc-2. CONCLUSIONS: BML-111 attenuated lung injury in endotoxemic mice and mitigated endothelial hyperpermeability by upregulating the expression of junction proteins.


Sujet(s)
Lésion pulmonaire aigüe/prévention et contrôle , Endotoxémie/complications , Acides heptanoïques/usage thérapeutique , Agents protecteurs/usage thérapeutique , Lésion pulmonaire aigüe/métabolisme , Lésion pulmonaire aigüe/mortalité , Animaux , Marqueurs biologiques/métabolisme , Perméabilité capillaire/effets des médicaments et des substances chimiques , Endothélium vasculaire/effets des médicaments et des substances chimiques , Endothélium vasculaire/métabolisme , Endotoxémie/métabolisme , Acides heptanoïques/pharmacologie , Cellules endothéliales de la veine ombilicale humaine/effets des médicaments et des substances chimiques , Cellules endothéliales de la veine ombilicale humaine/métabolisme , Humains , Injections péritoneales , Lipopolysaccharides , Mâle , Souris , Souris de lignée C57BL , Agents protecteurs/pharmacologie , Répartition aléatoire , Protéines de la jonction serrée/métabolisme , Régulation positive/effets des médicaments et des substances chimiques
13.
Lab Invest ; 95(11): 1258-68, 2015 Nov.
Article de Anglais | MEDLINE | ID: mdl-26302186

RÉSUMÉ

Lipoxin A4 (LXA4), as an endogenously produced lipid mediator, promotes the resolution of inflammation. Previously, we demonstrated that LXA4 stimulated alveolar fluid clearance through alveolar epithelial sodium channel gamma (ENaC-γ). In this study, we sought to investigate the mechanisms of LXA4 in modulation of ENaC-γ in lipopolysaccharide (LPS)-induced inflammatory lung injury. miR-21 was upregulated during an LPS challenge and downregulated by LXA4 administration in vivo and in vitro. Serum miR-21 concentration was also elevated in acute respiratory distress syndrome patients as compared with healthy volunteers. LPS increased miR-21 expression by activation of activator protein 1 (AP-1). In A549 cells, miR-21 upregulated phosphorylation of AKT activation via inhibition of phosphatase and tensin homolog (PTEN), and therefore reduced the expression of ENaC-γ. In contrast, LXA4 reversed LPS-inhibited ENaC-γ expression through inhibition of AP-1 and activation of PTEN. In addition, an miR-21 inhibitor mimicked the effects of LXA4; overexpression of miR-21 abolished the protective effects of LXA4. Finally, both AKT and ERK inhibitors (LY294002 and UO126) blocked effects of LPS on the depression of ENaC-γ. However, LXA4 only inhibited LPS-induced phosphorylation of AKT. In summary, LXA4 activates ENaC-γ in part via the miR-21/PTEN/AKT signaling pathway.


Sujet(s)
Canaux sodium épithéliaux/métabolisme , Lipopolysaccharides/toxicité , Lipoxines/physiologie , microARN/métabolisme , Phosphohydrolase PTEN/métabolisme , Pneumopathie infectieuse/induit chimiquement , Protéines proto-oncogènes c-akt/métabolisme , Animaux , Lignée cellulaire , Régulation négative , Mâle , Pneumopathie infectieuse/enzymologie , Pneumopathie infectieuse/métabolisme , Rats , Rat Sprague-Dawley , Régulation positive
14.
Innate Immun ; 21(7): 698-705, 2015 Oct.
Article de Anglais | MEDLINE | ID: mdl-25979627

RÉSUMÉ

The AMP-activated protein kinase (AMPK)-mediated energy-sensing signals play important roles in reprogramming the expression of inflammatory genes. In the present study, the potential effects of the AMPK activator 5-aminoimidazole-4-carboxamide-1-ß-D-ribofuranoside (AICAR) were investigated in a mouse model with LPS/D-Gal-induced acute hepatitis. Our experimental data indicated that treatment with AICAR suppressed the elevation of plasma aminotransferases and alleviated the histopathological abnormalities in mice exposed to LPS/D-Gal. Treatment with AICAR also inhibited the LPS/D-Gal-induced up-regulation of TNF-α, NO and myeloperoxidase. In addition, the LPS/D-Gal-induced expression of pro-apoptotic factor Bax, cleavage of caspase-3, elevation of hepatic caspase-3, caspase-8, caspase-9 activities and induction of terminal deoxynucleotidyl transferase-mediated nucleotide nick-end labeling-positive cells were all suppressed by AICAR. These results suggested that the AMPK activator AICAR could attenuate LPS/D-Gal-induced acute hepatitis, which implies that AMPK might become a novel target for the treatment of inflammation-based liver disorders.


Sujet(s)
5-Amino-imidazole-4-carboxamide/analogues et dérivés , Hépatite animale/traitement médicamenteux , Hypoglycémiants/administration et posologie , Foie/effets des médicaments et des substances chimiques , Ribonucléotides/administration et posologie , AMP-Activated Protein Kinases/antagonistes et inhibiteurs , 5-Amino-imidazole-4-carboxamide/administration et posologie , 5-Amino-imidazole-4-carboxamide/pharmacologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Caspases/métabolisme , Modèles animaux de maladie humaine , Galactose/immunologie , Hépatite animale/induit chimiquement , Hépatite animale/immunologie , Humains , Lipopolysaccharides/immunologie , Foie/anatomopathologie , Mâle , Souris , Thérapie moléculaire ciblée , Monoxyde d'azote/métabolisme , Ribonucléotides/pharmacologie , Transaminases/sang , Facteur de nécrose tumorale alpha/métabolisme
15.
Neurosci Lett ; 550: 55-9, 2013 Aug 29.
Article de Anglais | MEDLINE | ID: mdl-23831349

RÉSUMÉ

Alzheimer's disease (AD) is characterized by the degeneration of basal forebrain cholinergic neurons, whose survival and function are affected by neurotrophins and their receptors. The impaired signaling pathway of brain-derived neurotrophic factor/tropomyosin-related kinase B (BDNF/TrkB) is considered to play an important role in AD pathogenesis. To explore the association of polymorphisms within the NTRK2 gene (encoding TrkB) and sporadic AD (sAD), a case-control study was conducted in a Chinese Han cohort including 216 sAD patients and 244 control participants. Five single nucleotide polymorphisms (SNPs), with four of them within the promoter region and one in intron, were selected and genotyped with a polymerase chain reaction-ligase detection reaction (PCR-LDR) method. No association was revealed between these SNPs or the haplotypes containing four promoter SNPs and the risk of sAD. The results of this study indicate that polymorphisms in the selected regions of the NTRK2 gene are unlikely to confer the susceptibility of sAD in the Chinese Han population.


Sujet(s)
Maladie d'Alzheimer/génétique , Asiatiques/génétique , Récepteur trkB/génétique , Sujet âgé , Sujet âgé de 80 ans ou plus , Allèles , Maladie d'Alzheimer/ethnologie , Études cas-témoins , Chine , Femelle , Fréquence d'allèle , Études d'associations génétiques , Prédisposition génétique à une maladie , Génotype , Haplotypes , Humains , Mâle , Adulte d'âge moyen , Polymorphisme de nucléotide simple , Régions promotrices (génétique)
16.
Transfusion ; 53(12): 3080-7, 2013 Dec.
Article de Anglais | MEDLINE | ID: mdl-23560475

RÉSUMÉ

BACKGROUND: The aim of blood transfusion risk management is to improve the quality of blood products and to assure patient safety. We utilize failure mode and effect analysis (FMEA), a tool employed for evaluating risks and identifying preventive measures to reduce the risks in blood transfusion. STUDY DESIGN AND METHODS: The failure modes and effects occurring throughout the whole process of blood transfusion were studied. Each failure mode was evaluated using three scores: severity of effect (S), likelihood of occurrence (O), and probability of detection (D). Risk priority numbers (RPNs) were calculated by multiplying the S, O, and D scores. The plan-do-check-act cycle was also used for continuous improvement. RESULTS: Analysis has showed that failure modes with the highest RPNs, and therefore the greatest risk, were insufficient preoperative assessment of the blood product requirement (RPN, 245), preparation time before infusion of more than 30 minutes (RPN, 240), blood transfusion reaction occurring during the transfusion process (RPN, 224), blood plasma abuse (RPN, 180), and insufficient and/or incorrect clinical information on request form (RPN, 126). After implementation of preventative measures and reassessment, a reduction in RPN was detected with each risk. The failure mode with the second highest RPN, namely, preparation time before infusion of more than 30 minutes, was shown in detail to prove the efficiency of this tool. CONCLUSIONS: FMEA evaluation model is a useful tool in proactively analyzing and reducing the risks associated with the blood transfusion procedure.


Sujet(s)
Réaction transfusionnelle , Humains , Appréciation des risques , Gestion du risque
17.
Shock ; 33(6): 576-82, 2010 Jun.
Article de Anglais | MEDLINE | ID: mdl-19953002

RÉSUMÉ

Recent reports have indicated that IL-1[beta] is excessively released into the circulation during sepsis, and the expression level is closely correlated with the clinical course. Polymorphisms in the promoter region of IL-1B have been shown to affect LPS-induced IL-1[beta] transcription in vitro and IL-1[beta] plasma levels in healthy adults and to confer susceptibility to inflammatory diseases. However, it is not clear whether they confer susceptibility to sepsis after major trauma. The aim of this study was to search for association of polymorphisms (-1470G/C, -511T/C, and -31C/T) in the IL-1B gene promoter with the susceptibility to sepsis in a cohort of 238 major trauma patients. Genotyping of each patient for the three single-nucleotide polymorphisms was performed by restriction fragment length polymorphism-polymerase chain reaction method. Multivariate logistic regression analysis showed that the -1470 and -31 polymorphisms were associated with IL-1[beta] production by peripheral leukocytes in response to ex vivo LPS stimulation in an allele dose-dependent manner. Moreover, trauma patients carrying the -1470G or -31T alleles were more likely to develop sepsis compared with those with the -1470C or -31C allele (P = 0.014 and P = 0.038, respectively). Of the eight possible haplotypes composed of the three loci, the GCT and CTC haplotypes were associated with significantly higher and lower IL-1[beta] secretion (P = 0.005 and P = 0.035, respectively). Moreover, the GCT haplotype imparted higher risk of sepsis after severe injury (P = 0.04; odds ratio, 1.131; 95% confidence interval, 1.013-1.678). GCT homozygote patients also showed higher multiple organ dysfunction scores than CTC homozygote patients (P = 0.048). These data suggest that the IL-1[beta] promoter polymorphisms -1470G/C, -511T/C, and -31C/T may be functional both in vitro and in vivo. It may be possible to use these polymorphisms as relevant risk estimates for sepsis in trauma patients.


Sujet(s)
Interleukine-1 bêta/génétique , Polytraumatisme/génétique , Sepsie/génétique , Adulte , Femelle , Haplotypes , Humains , Lipopolysaccharides/toxicité , Mâle , Polytraumatisme/complications , Polymorphisme de nucléotide simple , Sepsie/étiologie
18.
Biochem Biophys Res Commun ; 382(1): 140-4, 2009 Apr 24.
Article de Anglais | MEDLINE | ID: mdl-19265672

RÉSUMÉ

A growing number of researchers have recognized the importance of using lipopolysaccharide (LPS) as target for the prevention and treatment of sepsis. However, no drugs targeting LPS have been applied clinically. In this study, LPS-inhibiting aptamers were screened by Systematic Evolution of Ligands by Exponential Enrichment (SELEX), and their therapeutic effects for experimental sepsis were observed. After 12 rounds of screening, 46 sequences were obtained. Primary structure analysis indicated that they had identical sequences, partly conserved sequences, or non-conserved sequences. Secondary structure analysis showed these sequences usually contained hairpin or stem-loop structures. Aptamer 19 significantly decreased NF-kappaB activation of monocytes challenged by LPS and reduced the IL-1 and TNF-alpha concentration in the media of LPS-challenged monocytes. Furthermore, aptamer 19 significantly increased the survival rate of mice with endotoxemia. The results suggest that a novel LPS antagonizing aptamer was obtained by SELEX, which successfully treated experimental sepsis.


Sujet(s)
Aptamères nucléotidiques/usage thérapeutique , Endotoxémie/prévention et contrôle , Lipopolysaccharides/antagonistes et inhibiteurs , Animaux , Aptamères nucléotidiques/composition chimique , Aptamères nucléotidiques/pharmacologie , ADN simple brin , Évaluation préclinique de médicament , Humains , Souris , Souris de lignée C57BL , Monocytes/effets des médicaments et des substances chimiques , Facteur de transcription NF-kappa B/métabolisme , Conformation d'acide nucléique , Technique SELEX
19.
Crit Care Med ; 36(8): 2274-80, 2008 Aug.
Article de Anglais | MEDLINE | ID: mdl-18596635

RÉSUMÉ

OBJECTIVE: Several polymorphisms in the CD14 promoter have been reported to be associated with various inflammatory diseases. However, conflicting results have been shown in association studies in different populations. This study aimed to investigate the possible functional significance of both the G-1145A and T-159C polymorphisms in the CD14 promoter and their association with organ dysfunction and sepsis in adult trauma patients. DESIGN: Genetic, functional, and association studies. SETTING: National Key Laboratory of Trauma and Departments of Traumatic Surgery in two teaching hospitals. SUBJECTS: Three hundred twenty-five healthy volunteers and 105 patients with major trauma. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the five single nucleotide polymorphisms identified within CD14 promoter in a Chinese Han population, two single nucleotide polymorphisms (G-1145A and T-159C) were selected according to bioinformatics analysis. Promoter activity of polymorphisms was determined using the reporter gene assay. Plasma sCD14 and tumor necrosis factor-alpha levels were measured by enzyme-linked immunosorbent assay. Both single nucleotide polymorphisms significantly reduced transcriptional activity of the promoter, and were significantly associated with a decrease of inducible sCD14 and tumor necrosis factor-alpha production in an allele-dose effect. Moreover, trauma patients carrying the -1145 A or -159 C allele appeared to have a decreased risk of multiple organ dysfunction and sepsis. In addition, both polymorphisms had a marked synergistic effect. CONCLUSIONS: The CD14/-1145 and -159 polymorphisms are functional variants, which may function in a synergistic fashion, and could be used as biological risk predictors of multiorgan dysfunction and sepsis in trauma patients.


Sujet(s)
ADN/génétique , Antigènes CD14/génétique , Polymorphisme de nucléotide simple , Régions promotrices (génétique) , Plaies et blessures/physiopathologie , Adolescent , Adulte , Chine , Biologie informatique , Femelle , Génotype , Humains , Mâle , Adulte d'âge moyen , Polymorphisme génétique , RT-PCR , Plaies et blessures/sang
20.
J Cereb Blood Flow Metab ; 28(9): 1588-96, 2008 Sep.
Article de Anglais | MEDLINE | ID: mdl-18523439

RÉSUMÉ

In the present study, we observed the expression of toll-like receptor 4 (TLR4) and its downstream signal pathway in peripheral blood monocytes (PBMs) from patients with acute cerebral infarct (ACI). The expression of TLR4 and MyD88 by PBMs was determined by flow cytometry and reverse transcriptase-polymerase chain reaction, and nuclear factor-kappaB (NF-kappaB) activity was detected by electrophoretic mobility shift assay. Ischemia/reperfusion injury-induced cerebral edema, infarction area, and neurologic impairment scores were determined in MyD88 gene knockout mice. The results indicated a significant increase in circulating TLR4(+) monocytes in ACI patients as compared with the control group and the transient ischemia attack (TIA) group. This change paralleled an elevation in TLR4mRNA transcription and serum tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-6 in the ACI and TIA groups. Correlation analysis showed TLR4 expression to significantly correlate with cytokine levels and stroke severity. MyD88mRNA differed insignificantly among the three groups. Compared with wild-type mice, 6 h of cerebral ischemia followed by 24 h of reperfusion did not significantly change cerebral edema, cerebral infarction area, and neurologic impairment scores in MyD88 gene knockout mice. Compared with the control group, serum heat shock protein (HSP) 60 increased significantly in the ACI and TIA groups, leading to NF-kappaB activation in TLR4/CD14-transfected HEK293 cells. It is suggested that upregulated TLR4 expression on PMBs may act as one of the peripheral mechanisms of inflammatory injury after ACI. Moreover, circulating HSP60 may be a ligand for TLR4, which is involved in the peripheral mechanism of inflammatory injury after ACI, possibly through an MyD88-independent signal pathway.


Sujet(s)
Infarctus cérébral/anatomopathologie , Monocytes/métabolisme , Facteur de différenciation myéloïde-88/génétique , Récepteur de type Toll-4/génétique , Régulation positive/génétique , Animaux , Oedème cérébral , Encéphalopathie ischémique , Études cas-témoins , Cytokines/analyse , Régulation de l'expression des gènes , Humains , Inflammation/étiologie , Souris , Souris knockout , ARN messager/analyse , Indice de gravité de la maladie , Récepteur de type Toll-4/physiologie
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