Alteration of endothelial nitric oxide synthase expression in acute pulmonary embolism: a study from bench to bioinformatics

OBJECTIVE

This study sought to explore endothelial nitric oxide synthase (eNOS) expression in acute pulmonary thromboembolism (APE).

MATERIALS AND METHODS

eNOS expression in lung tissue and bone marrow-derived endothelial progenitor cells (BM-EPCs) from APE mouse models was assessed by immunohistochemistry and real-time PCR. A gene expression profile meta-analysis was performed on human venous thromboembolism (VTE) whole blood samples recorded in the Gene Expression Omnibus (GEO) repository. Significantly expressed genes were determined from the microarray data by unsupervised clustering and supervised classification. Selected sample data with significantly expressed genes were further analyzed by principal component analysis (PCA), followed by Bayesian probit regression. Key discriminate genes were further grouped and annotated using functional annotations and gene enrichments using the online Database for Annotation, Visualization and Integrated Discovery (DAVID) software (v. 6.7).

RESULTS

While eNOS expression was significantly higher, serum nitric oxide levels were significantly lower in APE mice (20.42 ± 2.15 μM) compared to controls (53.50 ± 5.69 μM, p<0.001). eNOS mRNA and protein levels were significantly upregulated in BM-EPCs from APE mice. GEO repository data reported 3,397 upregulated and 4,173 downregulated genes (including eNOS) in VTE patients. In this regression analysis, the significant principal component PC1 and PC2 (p<0.05) were useful in distinguishing the VTE classification. The coefficient value of eNOS was -0.47707 in PC1 and -0.08429 in PC2, which did have some proportions on these significantly discriminated components but did not contribute significantly to the VTE classification. Functional enrichment in terms of acetylation and phosphoproteins were high.

CONCLUSIONS

Our findings, therefore, suggest that expression of eNOS is significantly altered in APE and may be a potential peripheral blood biomarker. Modulation of eNOS expression may be used for APE treatment.

[Induction of peripheral blood mononuclear cells to hepatocyte-like cells and preliminary study of cell response to injury under the effect of acetaminophen]

Objective: To establish a method for the induction of peripheral blood mononuclear cells to hepatocyte-like cells, and preliminarily investigate cell response to injury under the effect of acetaminophen (APAP). Methods: The surface marker CD45 of peripheral blood mononuclear cells wase detected cells by using flow cytometry and immunofluorescence methods. The cellular morphology of induced hepatocyte-like cells was observed under an inverted microscope. Real-time fluorescent quantitative PCR (RT-PCR) was used to detect the expression level of hepatocyte-specific genes, such as cytochrome (CY) P1A2, CYP3A4, CYP2C9, albumin (ALB), alpha-fetoprotein (AFP), and hepatocyte nuclear factor (HNF)4α mRNA. Immunofluorescence method was used to detect intracellular hepatocyte markers AFP, HNF4α, and ALB expression at the protein level. Biochemical analyzer was used to detect hepatocyte-specific secretory functions of AFP, ALB, and urea. Luciferase chemiluminescence method was used to detect the activity of key drug metabolizing enzyme CYP3A4. Colorimetric assay was used to detect the effect of the drug acetaminophen on hepatocyte-like cells, and alanine aminotransferase (ALT) was used as an indicator of liver cell injury. The statistical differences between the data were compared with t-test and rank-sum test. Results: The positive expression rate of CD45 cell surface markers isolated from peripheral blood mononuclear cells was about 98%, and hepatocyte-like cell morphology changes appeared on 15th day of induction. Compared with isolated mononuclear cells, CYP1A2, CYP3A4, CYP2C9, ALB, AFP and HNF4α mRNA was markedly elevated. The expression level of AFP, ALB and HNF4α protein were equally increased, and the secretory function of AFP, ALB and urea were enhanced. Compared with primary hepatocytes, CYP1A2, CYP2C9, AFP, HNF4α mRNA, and CYP3A4 mRNA did not decrease. The expression levels of AFP, ALB, and HNF4α proteins in the cells did not decrease, and the secretory function of AFP, ALB, and urea did not decrease. In addition, the CYP3A4 enzyme activity produced by hepatocyte-like cells was similar to that of primary hepatocytes. Compared with hepatocyte-like cells incubated without APAP, hepatocyte-like cells incubated with APAP had higher ALT level. Under the effect of APAP, the ALT level of hepatocyte-like cells was higher than isolated mononuclear cells. Conclusion: Peripheral blood mononuclear cells can be induced into hepatocyte-like cells with partial characteristics of hepatocytes, including the activity of CYP3A4, a key enzyme of hepatocyte drug metabolism. Additionally, preliminarily ALT secretory features reflect the hepatocytes injury under the effect of acetaminophen.

Molecular characterization of multiresistant strains of Salmonella typhi from South Asia isolated in Ontario, Canada

Two hundred and fourteen isolates of Salmonella typhi submitted to our laboratory between 1992 and 1996 were tested for susceptibility to 20 antimicrobial agents. Forty-eight of the 214 isolates (22.4%), recovered from individuals who had travelled in South Asia, were multiresistant. Forty-four of the 48 isolates were resistant to ampicillin, chloramphenicol, tetracycline, streptomycin, sulfamethoxazole, trimethoprim, cotrimoxazole, ticarcillin, and piperacillin; the other four isolates were resistant to four to six agents. Forty-two of the multiresistant isolates belonged to Vi phage type E1, two isolates from the Punjab State belonged to phage type A, another from the Punjab State belonged to phage type E3, one isolate from Pakistan belonged to type M1, and one isolate from India belonged to type J1. Plasmids from 45 of 48 isolates showed a temperature-sensitive mechanism of transfer to Escherichia coli K-12 strains, characteristic of H1 incompatibility group plasmids. The majority of plasmids had an estimated molecular weight of 120 MDa and encoded both citrate utilization and mercury resistance. Plasmids from three isolates had an estimated molecular weight of 112-115 MDa; one of these isolates encoded citrate utilization but not mercury resistance. Analysis of isolates by pulsed-field gel electrophoresis after digestion with XbaI and SpeI indicated that the majority of multiresistant isolates shared a common restriction profile, while four isolates had unique patterns.

Brefeldin A enhances receptor-mediated transcytosis of transferrin in filter-grown Madin-Darby canine kidney cells

The effects of brefeldin A (BFA) on transferrin (Tf) transcellular transport, Tf receptor (TfR) distribution, and TfR-mediated endocytosis in filter-grown Madin-Darby canine kidney (MDCK) cells were studied. BFA (1.6 micrograms/ml) markedly enhanced the transcytosis of 125I-labeled Tf (125I-Tf) in both apical-to-basal and basal-to-apical directions; yet, BFA did not enhance the transcytosis of either native horseradish peroxidase (HRP) or membrane-bound HRP-poly(L-lysine) conjugates. Furthermore, this enhanced transcytosis of 125I-Tf was abolished either by competition with excess unlabeled Tf or by incubation at temperatures less than or equal to 25 degrees C. In addition, BFA treatment to MDCK cells: (a) increased 125I-Tf specific binding to the apical membrane and decreased 125I-Tf specific binding to the basal membrane; (b) decreased TfR recycling at the basolateral membrane; (c) altered the apical/basolateral distribution of TfRs in favor of the apical side; and (d) markedly increased 59Fe extraction, but not transcytosis, from apically endocytosed 59Fe-loaded Tf. These effects are consistent with a model in which BFA alters the traffic pattern of internalized Tf by decreasing basolateral TfR recycling, while diverting the nonrecycled fraction to the apical side of the cell. Our results indicate that, unlike the reported inhibition of polymeric IgA transcytosis (Hunziker, W., Whitney, J. A., and Mellman, I. (1991) Cell 67, 617-627), BFA can enhance the transcytosis of Tf in MDCK cells. Thus, by altering the intracellular traffic of ligand-receptor complexes, BFA can elicit either a decrease or an increase in transcytosis depending on the nature of the intracellular receptor processing.

Effect of polysaccharide krestin on glutathione peroxidase gene expression in mouse peritoneal macrophages

Polysaccharide krestin (PSK) is a protein-bound polysaccharide extracted from the sporophore Coriolus versicolor. Previously, we found that PSK could reduce the oxidative injury that oxidised low-density lipoprotein (Ox-LDL) produced in monocytes/macrophages, and therefore have some pro-phylactic or therapeutic effect on atherosclerosis. Glutathione peroxidases, including selenium-dependent glutathione peroxidase (SeGPx) and non-selenium-dependent glutathione peroxidase (non-SeGPx, also called glutathione S-transferase [GST]), play an important role in the defence against oxidative injury. In order to find out if the effects of PSK were associated with antioxidant enzymes, we investigated its effect on glutathione peroxidase activity and messenger RNA (mRNA) expression in mouse peritoneal macrophages. Results showed that PSK enhanced SeGPx and non-SeGPx activity, and increased SeGPx and GST-P (pi class GST) mRNA in mouse peritoneal macrophages. In addition, the induction by PSK of the two glutathione peroxidases could be blocked by cycloheximide (30 micrograms/mL), but 5 micrograms/mL actinomycin D and 50 micrograms/mL acetovanilone (a superoxide inhibitor) had no effect. We conclude that PSK improved glutathione peroxidase activity through transcriptional induction of mRNA expression.

[Study on the application of oral magnesium sulfate solution in split doses as bowel preparation for colonoscopy in elderly patients]

Objective: To evaluate the efficacy and safety of oral magnesium sulfate solution in split doses as bowel preparation in elderly patients undergoing colonoscopy. Methods: A total of 368 elderly patients undergoing colonoscopy were enrolled at PLA General Hospital. The patients were randomly divided into magnesium sulfate solution orally in split doses group (group A, n=178) and single dose group (group B, n=190). Parameters including general information, defecation frequency, Boston bowel preparation score (BBPS), detection rate of lesions and adverse reactions. Results: The frequency of defecations in group A was (7.6±1.4), more than that in group B (6.6±1.5) with statistical significance (P<0.05). The duration of bowel preparation in group A was (128.6±25.3) min, shorter than that of group B (165.4±29.7) min (P<0.05). The BBPS in group A was (8.09±0.67), better than that of group B (7.34±0.58) (P<0.05). The detection rates of intestinal polyps and micropolyps (diameter<0.5 cm) in group A were 73/178 (41.0%) and 51/178 (28.7%) respectively, compared with 58/190 (30.5%) and 37/190 (19.5%) in group B (both P<0.05). In group A, 8 patients reported adverse reactions as abdominal distension and discomfort. One patient had ST-T abnormality of electrocardiogram (ECG). No nausea or vomiting occurred, yet 2 cases needed enema for inadequate bowel preparation. Twenty-one cases in group B reported adverse events including 7 with nausea and vomiting. There were 13 patients treated with enema. Abnormal ECG was found in 4 patients in group B. The satisfaction rate of group A was 97.8%, higher than that of group B (91.6%) (P<0.05). Conclusions: The effect of bowel preparation of elderly patients with magnesium sulfate solution in split dose has a better tolerance, good cleaning effect and low incidence of adverse reactions. It is an ideal choice for the elderly to prepare colonoscopy.

Differentially Expressed Circulating Long-Noncoding RNAS in Premature Infants with Respiratory Distress Syndrome

Purpose

Recent studies have addressed the association between lung development and long-noncoding RNAs (lncRNAs). But few studies have investigated the role of lncRNAs in neonatal respiratory distress syndrome (RDS). Thus, this study aimed to compare the expression profile of circulating lncRNAs between RDS infants and controls.

Methods

10 RDS infants and 5 controls were enrolled. RDS patients were further divided into mild and severe RDS subgroups. Blood samples were collected for the lncRNA expression profile. Subsequently, differentially expressed lncRNAs were screened out. Bioinformatics analysis was applied to establish a co-expression network of differential lncRNAs and mRNAs, and predict the underlying biological functions.

Results

A total of 135 differentially expressed lncRNAs were identified, including 108 upregulated and 27 downregulated lncRNAs (fold-change>2 and P<0.05) among the three groups (non-RDS, mild RDS and severe RDS groups). Of these lncRNAs, four were selected as showing higher fold changes and validated by qRT-PCR. ENST00000470527.1, ENST00000504497.1, ENST00000417781.5, and ENST00000440408.5 were increased not only in the plasma of total RDS patients but also in the severe RDS subgroup. Gene Ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses showed that differentially expressed lncRNAs may play important roles in RDS through regulating PI3KAkt, RAS, MAPK, and TGF-β signaling pathways.

Conclusion

The present results found that ENST00000470527.1, ENST00000504497.1, ENST00000417781.5, and ENST00000440408.5 may be invol ved in RDS. This could provide new insight into research of the potential pathophysiological mechanisms of preterm RDS.

[Clinical characteristics of patients with chronic thromboembolic pulmonary hypertension]

Objective: To investigate the clinical characteristics of patients with chronic thromboembolic pulmonary hypertension (CTEPH). Methods: CTEPH cases consecutively admitted into China-Japan Friendship Hospital from September 2015 to June 2019 were enrolled with prospective data collection. The medical histories, clinical characteristics, laboratory tests, imaging manifestation and hemodynamic parameters were analyzed. Patients were divided into high pulmonary vascular resistance (PVR) group and low PVR group according to the PVR level>1 000 dyn·s·cm(-5) or not, and clinical characteristics were compared between these two groups. Results: In the 148 cases of CTEPH, right heart catheterization was performed in 103 cases with mPAP (45.1±11.0) mmHg and PVR of (992±430) dyn·s·cm(-5). At diagnosis, 88 (59.5%) cases were in WHO functional class Ⅲ and 27 (18.2%) in class Ⅳ. Most common presenting symptoms were dyspnea (147, 99.3%), chest tightness (68, 45.9%), hemoptysis (42, 28.3%), syncope (30, 20.3%), and most common signs were P2 accentuation (95, 64.9%), edema (65, 43.9%), cyanosis (47, 31.8%), systolic murmur (44, 29.7%) and jugular vein distention (35, 23.6%). In 103 cases with right heart catheterization, 52 were in the low PVR group and 51 in high PVR group. Compared to the low PVR group, high PVR group patients had higher WHO functional class and more jugular vein distention (both P<0.05). In all the 148 cases, previous venous thromboembolism (VTE) was confirmed in 105 (70.9%) patients, with a higher prevalence of previous VTE in low PVR group than that in high PVR group (P<0.001). 30 (20.3%) patients had varicose veins of the lower extremities, and 21 (14.2%) had other thrombophilic disorders including antiphospholipid syndrome, protein C and S deficiency and antithrombin Ⅲ deficiency. Conclusions: Dyspnea, P2 accentuation and edema are the most common clinical presentation of CTEPH. Previous history of VTE is common in CTEPH patients with thrombophilia in some cases.

Simultaneous nitrogen and phosphorus removal through an integrated partial-denitrification/anammox process in a single UAFB system

With the aim of obtaining enhanced nitrogen removal and phosphate recovery in mainstream sewage, we examined an integrated partial-denitrification/anaerobic ammonia oxidation (PD/A) process over a period of 189 days to accomplish this goal. An up-flow anaerobic fixed-bed reactor (UAFB) used in the integrated PD/A process was started up with anammox sludge inoculated and the influent composition controlled. Results showed that the system achieved a phosphorus removal efficiency of 82% when the influent concentration reached 12.0 mg/L. Batch tests demonstrated that stable and efficient removal of chemical oxygen demand (COD), nitrogen, and phosphorus was achieved at a COD/NO3--N ratio of 3.5. Scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis indicated that hydroxyapatite was the main crystal in the biofilm. Furthermore, substrate variation along the axial length of UAFB indicated that partial denitrification and anammox primarily took place near the reactor's bottom. According to a microbiological examination, 0.4% of the PD/A process's microorganisms were anaerobic ammonia oxidizing bacteria (AnAOB). Ca. Brocadia, Ca. Kuenenia, and Ca. Jettenia served as the principal AnAOB generals in the system. Thauera, Candidatus Accumulibacter, Pseudomonas, and Acinetobacter, which together accounted for 27% of the denitrifying and phosphorus-accumulating bacteria, were helpful in advanced nutrient removal. Therefore, the combined PD/A process can be a different option in the future for sewage treatment to achieve contemporaneous nutrient removal.

Measurements of Chemical Potentials in Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

This Letter presents the most precise measurement to date of the matter-antimatter imbalance at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair sqrt[s_{NN}]=5.02  TeV. Using the Statistical Hadronization framework, it is possible to obtain the value of the electric charge and baryon chemical potentials, μ_{Q}=-0.18±0.90  MeV and μ_{B}=0.71±0.45  MeV, with unprecedented precision. A centrality-differential study of the antiparticle-to-particle yield ratios of charged pions, protons, Ω baryons, and light (hyper)nuclei is performed. These results indicate that the system created in Pb-Pb collisions at the LHC is on average baryon-free and electrically neutral at midrapidity.

Observation of Medium-Induced Yield Enhancement and Acoplanarity Broadening of Low-p_{T} Jets from Measurements in pp and Central Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The ALICE Collaboration reports the measurement of semi-inclusive distributions of charged-particle jets recoiling from a high transverse momentum (high p_{T}) hadron trigger in proton-proton and central Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. A data-driven statistical method is used to mitigate the large uncorrelated background in central Pb-Pb collisions. Recoil jet distributions are reported for jet resolution parameter R=0.2, 0.4, and 0.5 in the range 7 Collapse

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Oxidative and malondialdehyde modification of low-density lipoprotein: a comparative study of binding and degradation by macrophages and endothelial cells

Comparative study of oxidatively modified low-density lipoprotein (Ox-LDL) and malondialdehyde-modified low-density lipoprotein (MDA-LDL) is important for further understanding the biological properties of Ox-LDL, such as its toxic effects, immunogenicity and multiplicity of scavenger receptor binding. In this study, the characteristics of Ox-LDL and MDA-LDL binding and degradation were compared. The results show that when their degree of modification (as determined by relative electrophoretic mobility) was similar, the binding and degradation of Ox-LDL by the macrophage cell line P388D1 were greater than those of MDA-LDL. The binding and degradation of Ox-LDL by macrophages and human umbilical vein endothelial cells increased with the degree of modification. In addition, Ox-LDL or MDA-LDL could competitively inhibit binding of labelled Ox-LDL or labelled MDA-LDL to their respective macrophage receptors, and could partially inhibit each other.

Formation and characteristics of filamentous granular sludge

Aerobic granular sludge process as a promising biotechnology has been one of the research hotspots in the area of wastewater treatment during the last two decades. In our study, after around 60 days' operation, filamentous granular sludge (FGS) was formed under low aeration (SAV = 0.085 cm/s) and multi-feeding conditions. The characteristics of FGS and the performance of the FGS system for organic matter and nutrients removal were investigated. The results showed that chemical oxygen demand (COD) and total organic carbon (TOC) removal efficiencies were relatively stable, while COD removal efficiency increased from 82% to 94% in the presence of sulfamethoxazole (SMZ) at low concentration (1 mg/L). At the same time, the TP removal efficiency could be improved and maintained at around 75%, while TN removal efficiency was flocculated at around 50%. The analysis of microbial diversity showed that Thiothrix and Trichococcus as typical filamentous species were detected and dominant in the FGS system. The abundance of Thiothrix increased from 15% to 34%, while Trichococcus decreased from 23% to 3% in the presence of SMZ.

Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at sqrt[s]=13  TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Δη|<1.8 and a transverse momentum of 1 Collapse

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