Regulation of alveolar macrophage death in pulmonary fibrosis: a review.

Pulmonary fibrosis (PF) is a disease in which excessive extracellular matrix (ECM) accumulation occurs in pulmonary mesenchyme, which induces the destruction of alveolar structures and poor prognosis. Macrophage death is responsible for ECM accumulation after alveolar epithelial injury in PF. Depending on the local micro-environments, macrophages can be polarized to either classically activated (M1) or alternatively activated (M2) macrophage phenotypes. In general, M1 macrophages can promote inflammation and sterilization, stop the continuous damage process and prevent excessive repair, while M2 macrophages are anti-inflammatory and promote tissue repair, and excessive M2 macrophage activity may inhibit the absorption and degradation of ECM. Emerging evidence has revealed that death forms such as pyroptosis mediated by inflammasome affect polarization direction and ultimately lead to the development of PF. Pharmacological manipulation of macrophages death signals may serve as a logical therapeutic strategy for PF. This review will focus on the current state of knowledge regarding the regulation and underlying mechanisms of macrophages and their mediators in the influence of macrophage death on the development of PF. We expect to provide help in developing effective therapeutic strategies in clinical settings.

FSTL1 promotes alveolar epithelial cell aging and worsens pulmonary fibrosis by affecting SENP1-mediated DeSUMOylation.

Alveolar epithelial cell (AEC) senescence-induced changes of lung mesenchymal cells are key to starting the progress of pulmonary fibrosis. Follistatin-like 1 (FSTL1) plays a central regulatory role in the complex process of senescence and pulmonary fibrosis by enhancing transforming growth factor-ß1 (TGF-ß1) signal pathway activity. Activation of Smad4 and Ras relies on SUMO-specific peptidase 1 (SENP1)-mediated deSUMOylation during TGF-ß signaling pathway activation. We hypothesized that SENP1-mediated deSUMOylation may be a potential therapeutic target by modulating FSTL1-regulated cellular senescence in pulmonary fibrosis. In verifying this hypothesis, we found that FSTL1 expression was upregulated in the lung tissues of patients with idiopathic pulmonary fibrosis and that SENP1 was overexpressed in senescent AECs. TGF-ß1-induced FSTL1 not only promoted AEC senescence but also upregulated SENP1 expression. Interfering with SENP1 expression inhibited FSTL1-dependent promotion of AEC senescence and improved pulmonary fibrosis in mouse lungs. FSTL1 enhancement of TGF-ß1 signaling pathway activation was dependent on SENP1 in senescent AEC. Our work identifies a novel mechanism by which FSTL1 is involved in AEC senescence. Inhibition of SENP1 in epithelial cells alleviated pulmonary fibrosis by blocking FSTL1-enhanced TGF signaling.

SENP1 regulates the transformation of lung resident mesenchymal stem cells and is associated with idiopathic pulmonary fibrosis progression.

BACKGROUND: Lung resident mesenchymal stem cells (LR-MSCs) play an important role in idiopathic pulmonary fibrosis (IPF) by transforming into myofibroblasts, thereby losing their repair ability. Evidence suggests that key proteins of multiple signaling pathways are involved in myofibroblast differentiation of LR-MSCs, such as ß-Catenin and GLI family zinc finger 1 (GLI1). These proteins are regulated by SUMO (small ubiquitin-like modifier) modification, which is a post-translational modification that promotes protein degradation, while Sumo specific protein 1 (SENP1)-mediated deSUMOylation produces the opposite biological effects. Therefore, we speculated that SENP1 might be a potential target for treating pulmonary fibrosis by preventing the myofibroblast differentiation of LR-MSCs. METHODS: LR-MSCs were isolated from mice by using immunomagnetic beads. The extracted LR-MSCs were identified by flow cytometric analysis and multilineage differentiation assays. Lentivirus packaged shRNA silenced the expression of SENP1 in vitro and vivo. The silencing efficacy of SENP1 was verified by real-time quantitative PCR. The effect of down-regulated SENP1 on the myofibroblast differentiation of LR-MSCs was assessed by Immunofluorescence and Western blot. Immunoprecipitation was used to clarify that SENP1 was a key target for regulating the activity of multiple signaling pathways in the direction of LR-MSCs differentiation. LR-MSCs resident in the lung was analyzed with in vivo imaging system. HE and Masson staining was used to evaluate the therapeutic effect of LR-MSCs with SENP1 down-regulation on the lung of BLM mice. RESULTS: In this study, we found that the myofibroblast differentiation of LR-MSCs in IPF lung tissue was accompanied by enhanced SENP1-mediated deSUMOylation. The expression of SENP1 increased in LR-MSCs transition of bleomycin (BLM)-induced lung fibrosis. Interfering with expression of SENP1 inhibited the transformation of LR-MSCs into myofibroblasts in vitro and in vivo and restored their therapeutic effect in BLM lung fibrosis. In addition, activation of the WNT/ß-Catenin and Hedgehog/GLI signaling pathways depends on SENP1-mediated deSUMOylation. CONCLUSIONS: SENP1 might be a potential target to restore the repair function of LR-MSCs and treat pulmonary fibrosis. Video Abstract.

Value of peripheral perfusion index to predict acute limb ischaemia in newborns after peripheral artery cannulation.

AIMS AND OBJECTIVES: To investigate the feasibility of using peripheral perfusion index (PPI) to monitor acute limb ischaemia (ALI) in newborns after catheterisations. BACKGROUND: ALI is common complication of neonatal peripheral artery cannulation. It is important to address as soon as the early signs of ALI. PPI could aid in noninvasive evaluation of distal extremity perfusion in an effort to notify risk of potential ischaemic injury from catheterisations. DESIGN: A nested case-control study. METHODS: Clinical information of newborns who had been admitted to the Neonatal Intensive Care Unit of Jiangxi Provincial Children's Hospital and had received peripheral artery cannulation from January 2018 to January 2020 was prospectively collected. Transcutaneous blood oxygen saturation (TcSO2 ), PPI and delta-PPI (ΔPPI1; the difference in PPI values of the two arms. ΔPPI2; difference in the PPI values before and after cannulation) were recorded. We used STROBE checklist as an EQUATOR in this study. RESULTS: A total of 25 newborns with ALI were included in the study. These were then paired with 100 newborns without ALI. The PPI and TcSO2 of the cannulated limb were significantly lower in the ALI group than in the non-ALI (NALI) group (p < .05). The area under the receiver-operating characteristic curve was significant for ΔPPI1. The ΔPPI1 had a sensitivity and specificity of 92% and 87%, respectively, for diagnosing ALI. ΔPPI1 greater than 0.315 suggested that the infant was at risk of ALI. CONCLUSIONS: Monitoring the change in the PPI in newborns after catheterisations helped in the early assessment of ALI. RELEVANCE TO CLINICAL PRACTICE: Drops in the PPI and TcSO2 of the cannulated limbs might, to some extent, reflect the possibility of ALI in newborns. ΔPPI1 (the difference in PPI values of the two arms) proved to be a simple, objective parameter to predict the presence of ALI.

vgrG is separately transcribed from hcp in T6SS orphan clusters and is under the regulation of IHF and HapR.

V. cholerae, the causative agent of cholera epidemic, and V. fluvialis, the emerging foodborne pathogen, share highly homologous T6SS consisting of one large cluster and two small orphan or auxiliary clusters, and each of which was generally recognized as one operon. Here, we showed that the genes in each of the small clusters are organized into two transcriptional units. Specifically, the inner tube coding gene hcp/tssD is highly transcribed as one monocistron, while the tip component vgrG/tssI and its downstream effector and immunity genes are in one polycistron with very low transcriptional level. This conclusion is supported by qPCR analysis of mRNA abundance, reporter fusion analysis and transcriptional unit definition with RT-PCR analysis. Taking tssI2_a of V. fluvialis as an example, we further demonstrated that quorum sensing (QS) regulator HapR and global regulator IHF activate vgrG/tssI transcription by directly binding to its promoter region. Taken together, current studies deepen our understanding of T6SS system, highlighting its regulatory complexity during functional execution process.

Serum miR-22 is a novel prognostic marker for acute myeloid leukemia.

BACKGROUND: It has been demonstrated that aberrant expression of serum microRNAs is potential markers for the prognostic prediction of acute myeloid leukemia (AML). However, the clinical significance of serum miR-22 remained uncovered. In this study, we aimed to explore the potential prognostic value of serum miR-22 for AML. METHODS: Blood samples were collected from 124 patients with AML and 60 healthy individuals. Serum miR-22 level was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and its potential clinical value was investigated. RESULTS: Our results showed that serum miR-22 expression was significantly downregulated in AML subjects compared to healthy controls. Serum miR-22 levels were lowest in AML patients with M4/M5 subtypes, and low serum miR-22 expression occurred more frequently in AML patients with higher white blood cell counts or poor cytogenetic risk. Receiver operating characteristic (ROC) analysis revealed that serum miR-22 well differentiated AML cases from healthy controls. In addition, serum miR-22 downregulation was closely associated with worse clinical features and shorter survival. Low serum miR-22 expression was confirmed to be an independent predictor for overall survival and relapse-free survival in AML patients. Moreover, the expression level of serum miR-22 was dramatically increased following treatment. In addition, serum miR-22 levels were significantly higher in AML patients achieving complete remission (CR) than those without CR. CONCLUSION: Collectively, serum miR-22 might serve as a novel and promising prognostic biomarker for AML.

SMYD3 induces sorafenib resistance by activating SMAD2/3-mediated epithelial-mesenchymal transition in hepatocellular carcinoma.

Drug resistance prominently hampers the effects of systemic therapy of sorafenib to hepatocellular carcinoma (HCC). Epigenetics have critical regulatory roles in drug resistance. However, the contributions of histone methylatransferase SET and MYND domain containing 3 (SMYD3) to sorafenib resistance in HCC remain largely unknown. Here, using our established sorafenib-resistant HCC cell and xenograft models, we found SMYD3 was markedly elevated in sorafenib-resistant tumors and cells. Functionally, loss- and gain-of-function studies showed that SMYD3 promoted the migration, invasion, metastasis and stemness of sorafenib-resistant HCC cells. Mechanistically, SMYD3 is required for SMAD2/3-mediated epithelial-mesenchymal transition (EMT) in sorafenib-resistant HCC cells by interacting with SMAD2/3 and epigenetically promoting the expression of SOX4, ZEB1, SNAIL1 and MMP9 genes. In summary, our data demonstrate that targeting SMYD3 is an effective approach to overcome sorafenib resistance in HCC.

Knowledge, attitudes and practices of enhanced recovery after surgery among paediatric surgical nurses in China: A Cross-Sectional study.

AIM: To investigate paediatric surgical nurses' knowledge, attitudes and practices (KAP) regarding enhanced recovery after surgery (ERAS). DESIGN: A cross-sectional study. METHODS: A 34-question survey was developed. An electronic version of the questionnaire was distributed to nurses working in paediatric surgical departments of 22 tertiary hospitals from 14 provinces of China by means of convenience sampling from February to April 2021. A total of 855 nurses' data was used as the final sample. The statistical analysis included nonparametric test, Spearman's correlation and multiple linear regression. RESULTS: There is still room for improvement regarding the KAP of paediatric surgical nurses, especially in the knowledge of "postoperative recovery" and "preoperative preparation". The influencing factors of KAP were educational level, geographical region (South, Central, North, Northwest), years of work experience, hospital category (general hospital, women and children's hospital), and familiarity with ERAS.

TssI2-TsiI2 of Vibrio fluvialis VflT6SS2 delivers pesticin domain-containing periplasmic toxin and cognate immunity that modulates bacterial competitiveness.

Vibrio fluvialis is a halophilic Gram-negative bacterium regarded as an emerging unusual enteric pathogen of increasing public health concern. Our previous work has identified two type VI secretion systems (T6SSs) in V. fluvialis, VflT6SS1, and VflT6SS2, and the latter is functional in mediating interbacterial competitiveness. However, its antibacterial effectors remain to be clarified. In this work, we focused on a new potential effector/immunity pair TssI2/TsiI2. Bioinformatics analysis revealed that the C-terminal domain of TssI2 belongs to a widespread family of pesticin, and its antibacterial toxicity and corresponding protection by TsiI2 were proved via bacterial killing assays, and their action sites were localized to the periplasm of bacterial cells. The interaction of TssI2 and TsiI2 was demonstrated by the bacterial adenylate cyclase two-hybrid, protein pull-down and isothermal titration calorimetry assays. Site-directed mutagenesis demonstrated that, in addition to Glu-844, Thr-863, and Asp-869, which correspond to three reported residues in pesticin of Yersinia pestis, additional residues including Phe-837, Gly-845, Tyr-851, Gly-867, Gln-963, Trp-975, and Arg-1000 were also proved to be crucial to the bactericidal activity of TssI2. Muramidase/lysozyme-related peptidoglycan (PG) hydrolase activities of TssI2 and its variants were validated with permeabilized Escherichia coli cells and purified PG substrate. Based on sequence homologies at C-terminals in various V. fluvialis isolates, TssI2 was subdivided into five clusters (12-22% identity among them), and the antibacterial activities of representative effectors from other four Clusters were also confirmed through periplasmic over-expression in E. coli host. Two selected cognate immunities were proved to confer protection against the toxicities of their effectors. Additionally, TsiI2, which belongs to Cluster I, exhibited cross-protection to effector from Cluster V. Together, current findings expand our knowledge of the diversity and consistency of evolved VgrG effectors in V. fluvialis and on how VflT6SS2 mediates a competitive advantage to gain a better survival.

Optimization of Early Antimicrobial Strategies for Lung Transplant Recipients Based on Metagenomic Next-Generation Sequencing.

The management of perioperative antibiotic options after lung transplantation varies widely around the world, but there is a common trend to limit antibiotic use duration. Metagenomic next-generation sequencing (mNGS) has become a hot spot in clinical pathogen detection due to its precise, rapid, and wide detection spectrum of pathogens. Thus, we defined a new antibiotic regimen adjustment strategy in the very early stage (within 7 days) after lung transplantation mainly depending on mNGS reports combined with clinical conditions to reduce the use of antibiotics. To verify the clinical effect of the strategy, we carried out this research. Thirty patients who underwent lung transplantation were finally included, whose information including etiology, antibiotic adjustment, and the effect of our strategy was recorded. Lung transplant recipients in this study were prescribed with initial antibiotic regimen immediately after surgery; their antibiotic regimens were adjusted according to the strategy. According to our study, the entire effectiveness of the strategy was 90.0% (27/30). Besides, a total of 86 samples containing donor lung tissue, recipient lung tissue, and bronchoalveolar lavage fluid (BALF) were obtained in this study; they were all sent to mNGS test, while BALF was also sent to pathogen culture. Their results showed that the positive rate of BALF samples was higher (86.67%) than that of donor's lung tissue (20.0%) or recipient's lung tissue (13.33%) by mNGS test, indicating BALF samples are more valuable than other clinical samples from early postoperative period to guide the early adjustment of antibiotics after lung transplantation. It is effective for mNGS combined with traditional methods and clinical situations to optimize antibiotic regimens in lung transplantation recipients within 7 days after surgery.

A study on the esophageal dynamics in patients with gastroesophageal reflux disease and with refractory cough undergoing esophageal high-resolution manometry.

OBJECTIVE: To analyze the esophageal dynamics in patients with gastroesophageal reflux disease (GERD) and with refractory cough while undergoing esophageal high-resolution manometry (HRM). METHODS: A total of 32 patients with GERD and with refractory cough and 48 patients with GERD admitted to our hospital from February 2019 to July 2020 were assigned to the combined group and the GERD group, respectively, and 40 healthy volunteers were assigned to the healthy group. All the patients underwent HRM. The lower esophageal sphincter (LES) and the upper esophageal sphincter (UES) parameters, the types of peristalsis of the esophageal body, the esophageal body motility, the i relaxation of LES and UES incidence rates, and the esophageal body motility disorders were compared among the three groups. RESULTS: The combined group and the GERD group had lower esophageal sphincter pressure (LESP) levels and lower 4-s integrated relaxation pressure (4 s IRP) levels, shorter lower esophageal sphincter lengths (LESL), and higher frequencies and longer durations of transient lower esophageal sphincter relaxation (TLESR) compared with the healthy group (P < 0.05). The upper esophageal sphincter lengths (UESL) in the GERD group were longer than they were in the healthy group (P < 0.05). Compared with the healthy group and the GERD group, the combined group had longer distal latencies (DL), break distances, and peristaltic breaks (PB), longer large and small peristaltic breaks, a greater number of ineffective swallows, lower upper esophageal sphincter pressure (UESP) levels, distal contraction integrals (DCI), contractile front velocities (CFV), and a higher incidence rate of esophageal body motility disorders (P < 0.05). CONCLUSION: Patients with GERD and with refractory cough often also have esophageal body motility disorders, longer PB, elevated UESP levels, and lower DCI. HRM can be used to objectively evaluate the esophageal dynamics and to differentiate among diseases.

Analysis of risk factors of acute kidney injury in perioperative patients after lung transplantation.

BACKGROUND: This study sought to examine the factors influencing acute kidney injury (AKI) in the perioperative period after lung transplantation (LT). METHODS: We collected and analyzed the clinical data of 25 patients, who were diagnosed with AKI in the perioperative period after LT at Sichuan Provincial People's Hospital from July 1, 2018 to June 30, 2020. Based on the clinical outcomes, the patients were divided into an AKI group and a non-AKI group. Differences between the two groups were compared, including differences in mechanical ventilation (MV) time and intensive care unit (ICU) stay time, the mode of transplantation, the total amount of dehydration in the first week after surgery, use of potential kidney damaging drugs, and whether extracorporeal membrane oxygenation (ECMO) was used. RESULTS: Nineteen patients (76%) were diagnosed with AKI in the perioperative period after LT. There were no statistically significant differences between the two groups in terms of basic information, the mode of transplantation, the total amount of dehydration in the first week after surgery, the daily dose of tacrolimus, whether ganciclovir was used, whether voriconazole was used, whether ECMO was used, and mortality (P>0.05). However, the MV time and ICU stay time of the AKI group was longer than that of the non-AKI group (P=0.006, 0.011, respectively). Analysis within the group shows there were no significant differences in terms of mortality, the MV time, and the ICU stay time between the AKI stage two group and the AKI stage three group (all P>0.05). A multi-factor analysis was conducted in which AKI was the dependent variable, whether an amount of dehydration greater than 2,000 mL, a body mass index (BMI) greater than 18, and the use of ganciclovir and voriconazole had been examined as an independent variable; however, none of these were found to be risk factors associated with AKI. CONCLUSIONS: The incidence of AKI in the perioperative period after LT is high. AKI in the perioperative period after LT prolonged patients' MV time and ICU stay time. In the perioperative management of LT, it is necessary to consider kidney protection to reduce the risk of AKI.

CqsA/LuxS-HapR Quorum sensing circuit modulates type VI secretion system VflT6SS2 in Vibrio fluvialis.

Vibrio fluvialis is an emerging enteric pathogen of increasing public health threat. Two quorum sensing (QS) systems, VfqI-VfqR and CqsA/LuxS-HapR, and two type VI secretion systems (T6SSs), VflT6SS1 and VflT6SS2, have been identified in V. fluvialis. Whether there exists any correlation between the two systems is unclear. In this study, we found that CqsA/LuxS-HapR circuit regulator LuxO represses while HapR activates VflT6SS2. The effect of LuxO is more pronounced at low cell density and is HapR-dependent. Deletion of hapR abolished Hcp expression and alleviated antibacterial virulence. However, these effects were rescued by HapR-expressing plasmid. Reporter fusion analyses showed that HapR is required for the promoter activities of VflT6SS2. Sequence inspection of the major cluster promoter revealed two potential Motif 1 HapR binding sites, and their bindings to HapR were confirmed by both electrophoretic mobility shift assay (EMSA) and DNase I footprinting assay. Meanwhile, two single Motif 2 sites were identified in tssD2_a (hcpA) and tssD2_b (hcpB) promoter regions of the orphan cluster which are less conserved and displayed lower affinities to HapR. Together, our study demonstrated that CqsA/LuxS-HapR QS manipulate VflT6SS2 in V. fluvialis, and this finding will enhance our understanding of possible crosstalk between T6SS and QS in microbes.

A retrospective study of community-acquired Clostridium difficile infection in southwest China.

To identify the prevalence and characteristics of community-acquired Clostridium difficile infection (CA-CDI) in southwest China, we conducted a cross-sectional study. 978 diarrhea patients were enrolled and stool specimens' DNA was screened for virulence genes. Bacterial culture was performed and isolates were characterized by PCR ribotyping and multilocus sequence typing. Toxin genes tcdA and/or tcdB were found in 138/978 (14.11%) cases for fecal samples. A total of 55 C. difficile strains were isolated (5.62%). The positive rate of toxin genes and isolation results had no statistical significance between children and adults groups. However, some clinical features, such as fecal property, diarrhea times before hospital treatment shown difference between two groups. The watery stool was more likely found in children, while the blood stool for adults; most of children cases diarrhea ≤3 times before hospital treatment, and adults diarrhea >3 times. Independent risk factor associated with CA-CDI was patients with fever. ST35/RT046 (18.18%), ST54/RT012 (14.55%), ST3/RT001 (14.55%) and ST3/RT009 (12.73%) were the most distributed genotype profiles. ST35/RT046, ST3/RT001 and ST3/RT009 were the commonly found in children patients but ST54/RT012 for adults. The prevalence of CA-CDI in Yunnan province was relatively high, and isolates displayed heterogeneity between children and adults groups.

Molecular Characterization of Clostridium difficile Isolates in China From 2010 to 2015.

Clostridium difficile infection (CDI) has become a worldwide public health problem causing high mortality and a large disease burden. Molecular typing and analysis is important for surveillance and infection control of CDI. However, molecular characterization of C. difficile across China is extremely rare. Here, we report on the toxin profiles, molecular subtyping with multilocus sequence typing (MLST) and PCR ribotyping, and epidemiological characteristics of 199 C. difficile isolates collected between 2010 through 2015 from 13 participating centers across China. We identified 35 STs and 27 ribotypes (RTs) among the 199 C. difficile isolates: ST35 (15.58%), ST3 (15.08%), ST37 (12.06%), and RT017 (14.07%), RT001 (12.06%), RT012 (11.56%) are the most prevalent. One isolate with ST1 and 8 isolates with ST 11 were identified. We identified a new ST in this study, denoted ST332. The toxin profile tcdA+tcdB+tcdC+tcdR+tcdE+CDT- (65.83%) was the predominant profile. Furthermore, 11 isolates with positive binary toxin genes were discovered. According to the PCR ribotyping, one isolate with RT 027, and 6 isolates with RT 078 were confirmed. The epidemiological characteristics of C. difficile in China shows geographical differences, and both the toxin profile and molecular types exhibit great diversity across the different areas.

Integration Host Factor Modulates the Expression and Function of T6SS2 in Vibrio fluvialis.

Vibrio fluvialis, an emerging foodborne pathogen of increasing public health concern, contains two distinct gene clusters encoding type VI secretion system (T6SS), the most newly discovered secretion pathway in Gram-negative bacteria. Previously we have shown that one of the two T6SS clusters, namely VflT6SS2, is active and associates with anti-bacterial activity. However, how its activity is regulated is not completely understood. Here, we report that the global regulator integration host factor (IHF) positively modulates the expression and thus the function of VflT6SS2 through co-regulating its major cluster and tssD2-tssI2 (also known as hcp-vgrG) orphan clusters. Specifically, reporter gene activity assay showed that IHF transactivates the major and orphan clusters of VflT6SS2, while deletion of either ihfA or ihfB, the genes encoding the IHF subunits, decreased their promoter activities and mRNA levels of tssB2, vasH, and tssM2 for the selected major cluster genes and tssD2 and tssI2 for the selected orphan cluster genes. Subsequently, the direct bindings of IHF to the promoter regions of the major and orphan clusters were confirmed by electrophoretic mobility shift assay (EMSA). Site-directed mutagenesis combined with reporter gene activity assay or EMSA pinpointed the exact binding sites of IHF in the major and orphan cluster promoters, with two sites in the major cluster promoter, consisting with its two observed shifted bands in EMSA. Functional studies showed that the expression and secretion of hemolysin-coregulated protein (Hcp) and the VflT6SS2-mediated antibacterial virulence were severely abrogated in the deletion mutants of ΔihfA and ΔihfB, but restored when their trans-complemented plasmids were introduced, suggesting that IHF mostly contributes to environmental survival of V. fluvialis by directly binding and modulating the transactivity and function of VflT6SS2.

[Efficacy of noninvasive ventilation on treatment of ARDS caused by severe pneumonia after kidney transplantation].

OBJECTIVE: To observe the clinical efficacy of noninvasive ventilation (NIV) on the treatment of acute respiratory distress syndrome (ARDS) caused by severe pneumonia after kidney transplantation. METHODS: The clinical data of 17 patients who were diagnosed as ARDS caused by severe pneumonia after kidney transplantation and treated with NIV in Sichuan Provincial People's Hospital from January 1st, 2014 to June 1st, 2016 were collected and retrospectively analyzed. According to the result of NIV treatment, the patients were divided into NIV success group (n = 9) and NIV failure group (n = 8). The differences in gender, age, underlying diseases, acute physiology and chronic health evaluation II (APACHE II) score, laboratory parameters on the day when ARDS was diagnosed, daily immunosuppressive dosage, NIV support condition and duration, arterial blood gas analysis and adverse reactions between the two groups were compared. Receiver operating characteristic curve (ROC) was plotted, and the predictive value of each parameters for NIV results was evaluated. RESULTS: The two groups were similar in gender, age, and underlying diseases. The APACHE II score, serum levels of procalcitonin (PCT) and brain natriuretic peptide (BNP), serum creatinine (SCr), daily tacrolimus dose, and NIV support condition in NIV failure group were significantly higher than those in NIV success group [APACHE II score: 16.7±5.7 vs. 10.3±2.1, PCT (µg/L): 32.8 (1.2, 187.7) vs. 0.3 (0.1, 2.9), BNP (ng/L): 832.4 (263.7, 1 180.2) vs. 157.0 (33.9, 218.5), SCr (µmol/L): 284.8 (90.5, 474.2) vs. 186.6 (76.7, 206.3), daily tacrolimus dose (mg): 3.6 (3.1, 4.0) vs. 2.6 (2.0, 3.5), inspiratory positive airway pressure (IPAP, cmH2O, 1 cmH2O = 0.098 kPa): 14.8±4.1 vs. 9.0±1.1, expiratory positive airway pressure (EPAP, cmH2O): 7.6±1.8 vs. 4.7±0.8, fraction of inspired oxygen (FiO2): 0.75±0.25 vs. 0.43±0.06, all P < 0.05], and the oxygenation index (PaO2/FiO2) after treatment was significantly lower than that of NIV success group [mmHg (1 mmHg = 0.133 kPa): 107.4±65.2 vs. 268.7±98.8, P < 0.05]. There was no significant difference in albumin (Alb), white blood cell count (WBC), daily mycophenolate mofetil dose, use of glucocorticold, NIV duration, pH value, arterial partial pressure of carbon dioxide (PaCO2), or the incidence of sputum drainage disorder or pneumothorax between the two groups. ROC curve analysis showed that the predictive value of APACHEII score, serum PCT and BNP levels, tacrolimus daily dosage and PaO2/FiO2 changes after NIV treatment for the efficacy of NIV was high, the area under the ROC curve (AUC) was 0.813, 0.778, 0.903, 0.778, 0.764, respectively; when the cut-off value of APACHE II score was 16.0, PCT was 4.1 µg/L, BNP was 180.5 ng/L, tacrolimus daily dosage was 2.5 mg, PaO2/FiO2 increased 49.5 mmHg, the sensitivity was 87.5%, 75.2%, 87.5%, 87.5% and 75.0%, respectively, and the specificity was 77.8%, 66.7%, 88.9%, 74.4%, 88.9%, respectively. However, SCr was not sensitive to the NIV effect prediction. CONCLUSIONS: NIV in the treatment of ARDS caused by severe pneumonia after kidney transplantation has a certain value. The fewer tacrolimus daily dosage, the lower APACHE II score and levels of PCT and BNP, the more effective promotion of PaO2/FiO2 after NIV treatment, and the better curative effect is suggested.

Distinct Expression Levels of ALS, LIP, and SAP Genes in Candida tropicalis with Diverse Virulent Activities.

Candia tropicalis is an increasingly important human pathogen, causing nosocomial fungemia among patients with neutropenia or malignancy. However, limited research has been published concerning its pathogenicity. Based on the phenotypes of C. tropicalis in our previous study, we selected nine representative strains with different activities of virulence factors (adhesion, biofilm formation, secreted aspartic proteinases, and hemolysins), and one reference strain, ATCC750. The present study aimed to investigate the filamentation ability, the expression of virulence genes (ALST1-3, LIP1, LIP4, and SAPT1-4) and the cell damage of C. tropicalis strains with diverse virulences. C. tropicalis exhibited strain-dependent filamentation ability, which was positively correlated with biofilm formation. Reverse transcriptase PCR analysis showed that the ALST3 and SAPT3 genes had the highest expression in their corresponding genes for most C. tropicalis. The expressions of virulence genes, except ALST3 on polystyrene, were upregulated compared with growth in the planktonic and on human urinary bladder epithelial cell line (TCC-SUP) surface. Clustering analysis of virulence genes showed that isolates had a high biofilm forming ability on polystyrene formed a group. Lactate dehydrogenase assays showed that the cell damage induced by C. tropicalis markedly increased with longer infection time (24 and 48 h). Strain FXCT01, isolated from blood, caused the most serious cell damage; while ZRCT52, which had no filamentation ability, caused the least cell damage. Correlation analysis demonstrated significant correlation existed between adhesion on epithelial cells or the expression of ALST2-3 and cell damage. Overall, our results supported the view that adhesion and filamentation may play significant roles in the cell damage caused by C. tropicalis.

Expression of Toll-like receptor 4 in lungs of immune-suppressed rat with Acinetobacter baumannii infection.

Toll-like receptor 4 (TLR4) is involved in the regulation of host responses to Acinetobacter baumannii (A. baumannii). The aim of the present study was to examine the function of TLR4 in lung inflammation in immune-suppressed rats with A. baumannii infection. A total of 72 Sprague-Dawley male rats were randomly divided into the control, A. baumannii infection and immune-suppressed infection groups. The immune-suppressed infection group was treated with 100 mg/kg hydrocortisone by subcutaneous injection every other day for 2 weeks prior to A. baumannii infection. Lung tissue was obtained on the 3rd and 7th day after tracheal inoculation with A. baumannii. The expression of TLR4 in bronchial and alveolar epithelial cells, and alveolar macrophage was examined using immunohistochemistry. The levels of interleukin (IL)-6, tumor necrosis factor (TNF)-α in bronchoalveolar lavage fluid were detected using ELISA. The results showed that in the control group, the expression of TLR4 was upregulated in the bronchial and alveolar epithelial, and alveolar macrophages, and the levels of IL-6 and TNF-α were increased in the early phase of A. baumannii infection. On the 7th day, no significant difference in the levels of IL-6 and TNF-α was observed between the A. baumannii infection and control groups. Conversely, the expression of TLR4 was downregulated in the immune-suppressed group, and the levels of IL-6 and TNF-α were reduced on the 3rd day after infection. In the subsequent observation period, the expression of TLR4 was upregulated and the levels of IL-6 and TNF-α were increased. In conclusion, the results show a critical role of TLR4 in mediating effective immune response in the lung of rat with A. baumannii infection.