Using Adaptive Imaging Parameters to Improve PEGylated Ultrasmall Iron Oxide Nanoparticles-Enhanced Magnetic Resonance Angiography.

The PEGylated ultrasmall iron oxide nanoparticles (PUSIONPs) exhibit longer blood residence time and better biodegradability than conventional gadolinium-based contrast agents (GBCAs), enabling prolonged acquisitions in contrast-enhanced magnetic resonance angiography (CE-MRA) applications. The image quality of CE-MRA is dependent on the contrast agent concentration and the parameters of the pulse sequences. Here, a closed-form mathematical model is demonstrated and validated to automatically optimize the concentration, echo time (TE), repetition time (TR) and flip angle (FA). The pharmacokinetic studies are performed to estimate the dynamic intravascular concentrations within 12 h postinjection, and the adaptive concentration-dependent sequence parameters are determined to achieve optimal signal enhancement during a prolonged measurement window. The presented model is tested on phantom and in vivo rat images acquired from a 3T scanner. Imaging results demonstrate excellent agreement between experimental measurements and theoretical predictions, and the adaptive sequence parameters obtain better signal enhancement than the fixed ones. The low-dose PUSIONPs (0.03 mmol kg-1 and 0.05 mmol kg-1) give a comparable signal intensity to the high-dose one (0.10 mmol kg-1) within 2 h postinjection. The presented mathematical model provides guidance for the optimization of the concentration and sequence parameters in PUSIONPs-enhanced MRA, and has great potential for further clinical translation.

Effect of comfortable nursing on postoperative nausea and vomiting in patients with idiopathic scoliosis after posterior orthopedic surgery.

Objective: To evaluate the effect of comfort nursing on postoperative nausea and vomiting in patients with idiopathic scoliosis undergoing posterior correction surgery. Methods: 92 patients with idiopathic scoliosis were taken as the subjects and segmented into a control group and an experimental group (n = 46/each group). The former received routine care, while the latter one performed comfortable care. The observation period is 48 h after surgery. Record and compare the incidence, grade, frequency, and pain level of nausea and vomiting in both groups, as well as postoperative physical signs and symptoms, drug use, and postoperative recovery. Investigating the patient's satisfaction with nursing care. The research data is analyzed using SPSS26.0 software. P < 0.05 means statistical significance. Results: Within 48 h after surgery, the number of nausea and vomiting in the control is 24 and the experimental group is 8, with an incidence rate of 52% and 16%. The latter is significantly lower than that in the control. The average number of nausea and vomiting episodes in the control is 2.5, significantly higher than the 0.45 episodes in the experimental set. There is a significant difference in the frequency of nausea and vomiting/temperature and urine volume/scores of nausea, vomiting, dizziness, headache, decreased appetite, and discomfort between the two groups (P < 0.05). Conclusion: Comfortable care has a relieving effect on postoperative nausea and vomiting in patients with idiopathic scoliosis after posterior correction surgery. It can low down the incidence and frequency of nausea and vomiting, and reduce the score of related symptoms. Comfortable care can also help patients recover after surgery, increase dietary intake, and improve nutritional status. Comfortable care has a significant effect on postoperative nausea and vomiting in cases with idiopathic scoliosis undergoing posterior correction surgery, which can improve their postoperative recovery and quality of life.

Rational design, synthesis, and antimicrobial evaluation of novel 1,2,4-trizaole-substituted 1,3,4-oxadiazole derivatives with a dual thioether moiety.

In this paper, a series of novel 1,2,4-trizaole-substituted 1,3,4-oxadiazole derivatives with a dual thioether moiety were constructed. The synthetic compounds were characterized by 1H NMR, 13C NMR, HRMS, and single crystal diffraction. The antimicrobial activities of title compounds against fungi (Pyricutaria oryzae Cav., Phomopsis sp., Botryosphaeria dothidea, cucumber Botrytis cinerea, tobacco Botrytis cinerea, blueberry Botrytis cinerea) and bacteria (Xanthomonas oryzae pv. oryzicola, Xoc; Xanthomonas axonopodis pv. citri, Xac) revealed these compounds possessed excellent antibacterial activity through mycelial growth rate method and turbidity method, respectively. Among them, compounds 7a, 7d, 7g, 7k, 7l, and 7n had the antibacterial inhibition rate of 90.68, 97.86, 93.61, 97.70, 97.26, and 92.34%, respectively. The EC50 values of 7a, 7d, 7g, 7k, 7l, and 7n were 58.31, 48.76, 58.50, 40.11, 38.15, and 46.99 µg/mL, separately, superior to that of positive control pesticide thiodiazole copper (104.26 µg/mL). The molecular docking simulation of compound 7l and glutathione s-transferase also confirmed its good activity. The in vivo bioassay toward Xac infected citrus leaves was also performed to evaluate the potential of compounds as efficient antibacterial reagent. Further study of antibacterial mechanism was also carried out, including extracellular polysaccharide production, permeability of bacterial membrane, and scanning electron microscope observations. The excellent antibacterial activities of these compounds provided a strong support for its application for preventing and control plant diseases.

Discovery of Novel Compounds for Combating Rising Severity of Plant Diseases Caused by Fungi and Viruses.

In recent years, the severity of plant diseases caused by plant pathogenic fungi and viruses has been on the rise. However, there is a limited availability of pesticide chemicals in the market for effectively controlling both fungal and viral infections. To solve this problem, a series of novel pyrimidine derivatives containing a 1,3,4-oxadiazole thioether fragment were synthesized. Among them, compound 6s exhibited remarkable in vivo protection activity against tobacco mosaic virus, demonstrating the superior 50% effective concentration (EC50) value of 0.42 µM, outperforming ningnanmycin (0.60 µM). Meanwhile, compound 6s exhibited remarkable antifungal activity against Botrytis cinerea Pers. in postharvest blueberry in vitro, with an EC50 value of 0.011 µM, surpassing the inhibition rate of Pyrimethanil (0.262 µM). Additionally, compound 6s also demonstrated remarkable curative and protection activities against blueberry fruit gray mold in vivo, with control efficiencies of 54.2 and 60.4% at 200 µg/mL concentration, respectively, which were comparable to those of Pyrimethanil (49.3 and 63.9%, respectively). Scanning electron microscopy showed that the compound 6s-treated hyphae of B. cinerea Pers. in postharvest blueberry became abnormally collapsed and shriveled. Furthermore, the molecular docking simulation demonstrated that compound 6s formed hydrogen bonds with SER-17, ARG-43, and SER-39 of succinate dehydrogenase (SDH), providing a possible explanation for the mechanism of action between the target compounds and SDH. This study represents the first report on the antiviral and antifungal activities of novel pyrimidine derivatives containing a 1,3,4-oxadiazole thioether fragment.

Analysis and fabrication of a small-scale radio-frequency balun for magnetic resonance imaging amplifier.

In this study, the authors report the design and fabrication of a small mixed-integrated balun for magnetic resonance imaging (MRI). The device was designed by using the positive anti-symmetric coupling method, which applies the lump surface-mount technology capacitors as well as mirror-symmetric coupling strips that were etched on the top and bottom layers of a printed circuit board. The capacitors reduced the length of the coupling strips and compensated for imbalances in the phase and gain due to errors in the fabrication process. The structure and equivalent even-odd circuit model of the device was modeled and examined using commercial software to optimize the design parameters. Following this, the device was fabricated and its performance was assessed through measurements using a network analyzer. The results showed that imbalances in the gain and phase were lower than 0.1 dB and 1°, respectively, and the insertion loss and the input voltage standing-wave ratio (VSWR) were lower than 0.4 dB and -25 dB, respectively. More importantly, the device was small, with dimensions of 50 × 60 × 1.5 mm. This makes it suitable for MRI applications involving highly integrated miniaturized systems. The proposed device was integrated into a 3.0 T radio-frequency power amplifier (RFPA) and reduced the dimensions of its power modules by 20% compared with the traditional balun. Finally, the RFPA module was used in an 3.0T MRI system for imaging experiments, and the results showed that the balun can help obtain high-quality scanning images.

Design, Synthesis, and Antifungal Activity of Novel 1,2,4-Triazolo[4,3-c]trifluoromethylpyrimidine Derivatives Bearing the Thioether Moiety.

Crop disease caused by fungi seriously affected food security and economic development. Inspired by the utilization of fungicide containing 1,2,4-triazole and trifluoromethylpyrimidine, a novel series of 1,2,4-triazolo[4,3-c]trifluoromethylpyrimidine derivatives bearing the thioether moiety were synthesized. Meanwhile, the antifungal activities of the title compounds were evaluated and most compounds exhibited obvious antifungal activities against cucumber Botrytis cinerea, strawberry Botrytis cinerea, tobacco Botrytis cinerea, blueberry Botrytis cinerea, Phytophthora infestans, and Pyricularia oryzae Cav. Among the compounds, 4, 5h, 5o, and 5r showed significant antifungal activities against three of the four Botrytis cinerea, which indicated the potential to become the leading structures or candidates for resistance to Botrytis cinerea.

Pedigree analysis of the EGFR p.V1010M germline mutation in a family with a family history of non-small-cell lung cancer.

Background: Tumors can be caused by genetic or environmental factors, but previous studies have shown that genetic factors contribute less to lung cancer than environmental factors. The epidermal growth factor receptor (EGFR) is the most common driver gene in non-small-cell lung cancer (NSCLC), but most variations are somatic. In this study, we reported on the pedigree of the EGFR p.V1010M germline mutation for the first time, and explored the correlation between the V1010M and the occurrence of NSCLC. Further, the effect of the V1010M on the treatment of the EGFR-tyrosine kinase inhibitors (TKIs) was investigated through the treatment of the proband with the simultaneous somatic mutation of the EGFR p.L858R. Methods: The family members were screened using next-generation sequencing (NGS) and Sanger sequencing, and the pedigree was analyzed to examine the relationship between the EGFR p.V1010M and the occurrence of NSCLC. Schrodinger software was used to predict the structural function of the mutant amino acid sequence proteins. Results: A total of 10 blood samples were collected from 4 generations of family members, many of whom had suffered from lung cancer. Six carriers of the EGFR p.V1010M were detected. The pedigree analysis showed that there was still no evidence of a correlation between the EGFR p.V1010M and disease occurrence. Additionally, the proband had the EGFR p.L858R somatic mutation, and the response after the treatment of gifitinib was stable disease (SD), which turned to progressive disease (PD) some 4 months later. Schrodinger software showed that the 1010th amino acid valine was located near the C terminal, and the variation to methionine had little effect on the structure of the EGFR dimer. Conclusions: This study is the first report on pedigree with the EGFR p.V1010M germline mutation. Further research needs to be conducted to determine whether this mutation is pathogenic, but it is likely related to EGFR-TKI resistance in NSCLC.

Rational Constructed Ultra-Small Iron Oxide Nanoprobes Manifesting High Performance for T1-Weighted Magnetic Resonance Imaging of Glioblastoma.

Precise diagnosis and monitoring of cancer depend on the development of advanced technologies for in vivo imaging. Owing to the merits of outstanding spatial resolution and excellent soft-tissue contrast, the application of magnetic resonance imaging (MRI) in biomedicine is of great importance. Herein, Angiopep-2 (ANG), which can simultaneously help to cross the blood-brain barrier and target the glioblastoma cells, was rationally combined with the 3.3 nm-sized ultra-small iron oxide (Fe3O4) to construct high-performance MRI nanoprobes (Fe3O4-ANG NPs) for glioblastoma diagnosis. The in vitro experiments show that the resultant Fe3O4-ANG NPs not only exhibit favorable relaxation properties and colloidal stability, but also have low toxicity and high specificity to glioblastoma cells, which provide critical prerequisites for the in vivo tumor imaging. Furthermore, in vivo imaging results show that the Fe3O4-ANG NPs exhibit good targeting ability toward subcutaneous and orthotopic glioblastoma model, manifesting an obvious contrast enhancement effect on the T1-weighted MR image, which demonstrates promising potential in clinical application.

Up-regulation of the manganese transporter SLC30A10 by hypoxia-inducible factors defines a homeostatic response to manganese toxicity.

Manganese (Mn) is an essential metal that induces incurable parkinsonism at elevated levels. However, unlike other essential metals, mechanisms that regulate mammalian Mn homeostasis are poorly understood, which has limited therapeutic development. Here, we discovered that the exposure of mice to a translationally relevant oral Mn regimen up-regulated expression of SLC30A10, a critical Mn efflux transporter, in the liver and intestines. Mechanistic studies in cell culture, including primary human hepatocytes, revealed that 1) elevated Mn transcriptionally up-regulated SLC30A10, 2) a hypoxia response element in the SLC30A10 promoter was necessary, 3) the transcriptional activities of hypoxia-inducible factor (HIF) 1 or HIF2 were required and sufficient for the SLC30A10 response, 4) elevated Mn activated HIF1/HIF2 by blocking the prolyl hydroxylation of HIF proteins necessary for their degradation, and 5) blocking the Mn-induced up-regulation of SLC30A10 increased intracellular Mn levels and enhanced Mn toxicity. Finally, prolyl hydroxylase inhibitors that stabilize HIF proteins and are in advanced clinical trials for other diseases reduced intracellular Mn levels and afforded cellular protection against Mn toxicity and also ameliorated the in vivo Mn-induced neuromotor deficits in mice. These findings define a fundamental homeostatic protective response to Mn toxicity-elevated Mn levels activate HIF1 and HIF2 to up-regulate SLC30A10, which in turn reduces cellular and organismal Mn levels, and further indicate that it may be possible to repurpose prolyl hydroxylase inhibitors for the management of Mn neurotoxicity.

A novel nomogram model for differentiating Kawasaki disease from sepsis.

Kawasaki disease (KD) is a form of systemic vasculitis that occurs in children under the age of 5 years old. Due to prolonged fever and elevated inflammatory markers that are found in both KD and sepsis, the treatment approach differs for each. We enrolled a total of 420 children (227 KD and 193 sepsis) in this study. Logistic regression and a nomogram model were used to analyze the laboratory markers. We randomly selected 247 children as the training modeling group and 173 as the validation group. After completing a logistic regression analysis, white blood cell (WBC), anemia, procalcitonin (PCT), C-reactive protein (CRP), albumin, and alanine transaminase (ALT) demonstrated a significant difference in differentiating KD from sepsis. The patients were scored according to the nomogram, and patients with scores greater than 175 were placed in the high-risk KD group. The area under the curve of the receiver operating characteristic curve (ROC curve) of the modeling group was 0.873, sensitivity was 0.893, and specificity was 0.746, and the ROC curve in the validation group was 0.831, sensitivity was 0.709, and specificity was 0.795. A novel nomogram prediction model may help clinicians differentiate KD from sepsis with high accuracy.

An Efficient Automated Radiosynthesis and Bioactivity Confirmation of VMAT2 Tracer [18F]FP-(+)-DTBZ.

PURPOSE: The aim of this study was to optimize the radiolabeling method of [18F]fluoropropyl-(+)-dihydrotetrabenazine ([18F]FP-(+)-DTBZ) to fulfill the demand of preclinical and clinical application. PROCEDURES: Optimized labeling conditions were performed by altering the molar ratio of precursor to base (P/B), base species, solvents, reaction temperature, reaction time, and precursor concentration through manual radiosynthesis of [18F]FP-(+)-DTBZ. The conditions with the highest radiochemical yield (RCY) were applied to automated radiosynthesis, and the crude product was purified with a Sep-Pak Plus C18 cartridge. Quality control and stability of [18F]FP-(+)-DTBZ were carried out by HPLC. In vitro cellular uptake and blocking assays were conducted in human neuroblastoma cell line SH-SY5Y. In vivo imaging with small animal positron emission tomography (microPET) was performed with Sprague-Dawley rats. RESULTS: Under the optimized conditions (P/K2CO3 = 1:8, heating at 120 °C for 3 min in dimethyl sulfoxide), an RCY of 88.7 % was obtained with 1.0 mg precursor. The optimized reaction conditions were successfully applied to an automated module and gave a high activity yield (AY) of 30-55 % in about 40 min with a > 99.0 % radiochemical purity (RCP) and a > 44.4 GBq/µmol molar activity (Am). Stability test displayed that the RCP retained > 98.0 % in 8 h in saline and in phosphate buffer saline (PBS, pH 7.4). In vitro cellular uptake assay showed accumulation of [18F]FP-(+)-DTBZ in SH-SY5Y cells, which could be significantly inhibited by vesicular monoamine transporter 2 (VMAT2) inhibitor DTBZ. MicroPET images of rat brain displayed that the striatum showed the highest uptake with a standardized uptake value (SUV) of 3.91 ± 0.30 at ~ 70 min. Co-injection with DTBZ (1.0 mg/kg) resulted in a 75 % decrease of the striatal SUV, confirming the specificity of [18F]FP-(+)-DTBZ to VMAT2. CONCLUSIONS: We obtained an optimized radiolabeling method of [18F]FP-(+)-DTBZ and successfully applied it to a commercial available module. The automated synthesis gave a high AY and RCP of [18F]FP-(+)-DTBZ with high and specific binding to VMAT2, facilitating its routine application for VMAT2 tracing.

A hybrid model combining wavelet transform and recursive feature elimination for running state evaluation of heat-resistant steel using laser-induced breakdown spectroscopy.

Heat-resistant steel is widely used in various industries, and the running state is of great importance for equipment function and safety. In this work, laser-induced breakdown spectroscopy (LIBS) is applied to evaluate the running state of steel using indicators of micro and macro properties. The hybrid model based on wavelet threshold denoising (WTD) and K-fold-support vector machine-recursive feature elimination (K-SVM-RFE) is proposed to estimate the different indictors of various service conditions of steel. Fourteen T91 specimens, including 4 industrial specimens obtained from different service conditions in the power plant boiler, were used as the analytes. Firstly, the noise signal of the LIBS spectra of each specimen was analyzed and removed with WTD. Secondly, an improved approach K-SVM-RFE was applied to select the optimal feature subset and build the classification models of aging grade and hardness grade. The influence of denoising pretreatment on model performance was compared and discussed. Finally, the assessment matrix, established using the indicators from the aging grade and hardness grade, was used to evaluate the running state of steel. The results show that the test assessment matrix obtained with the hybrid model based on WTD and K-SVM-RFE is consistent with the reference matrix on the running state of steel.

MicroRNA-155 regulates lipopolysaccharide-induced mucin 5AC overproduction via a suppressor of cytokine signaling 1-mediated mechanism in human bronchial epithelial cells.

Chronic inflammatory lung diseases accompanied by Gram-negative bacteria infection are characterized by excessive mucin production. Lipopolysaccharide (LPS), the major endotoxin released from Gram-negative bacteria, is a potent inflammatory agonist for mucin overproduction. In this study, we sought to examine whether the toll-like receptor (TLR)-responsive microRNA miR-155 plays a role in LPS-provoked induction of mucin 5AC (MUC5AC) and the potential role of suppressor of cytokine signaling 1 (SOCS1) involved in this process. We found that LPS increased the expression of MUC5AC in association with TLR4-dependent miR-155 induction. The suppression of miR-155 by antagomir led to an excessive production of SOCS1, thereby downregulation of MUC5AC production. Collectively, these data imply that miR-155 is involved in LPS-induced MUC5AC overproduction through a TLR4-dependent manner and thereby the downregulation of SOCS1.

Association of Single-Nucleotide Polymorphisms of C-Reactive Protein Gene with Susceptibility to Infantile Sepsis in Southern China.

BACKGROUND C-reactive protein (CRP) is an important biomarker of sepsis. Several single-nucleotide polymorphisms (SNPs) in the CRP gene can determine plasma CRP levels and are risk factors in many diseases, such as cancer, arteritis, and diabetes. However, it is unknown whether polymorphisms in CRP are associated with susceptibility to and outcome of infantile sepsis. We explored the effect of these SNPs on CRP response in infantile sepsis, and compared genetic data on patients with sepsis. MATERIAL AND METHODS A total of 49 infants with sepsis and 20 healthy infants were enrolled during hospitalization, and 3 SNPs in the CRP gene region (rs1205, rs2808530, and rs3091244) were genotyped and then analyzed for associations with CRP levels and sepsis. RESULTS The CRP means concentration results showed that mean CRP concentration was different in the 4 groups (healthy, sepsis, severe sepsis, and septic shock) and was positively correlated with the severity of infantile sepsis. There was also a difference in CRP SNP rs1205 between infants with septic shock and healthy infants, and between infants with septic shock and infants with sepsis. No differences were observed in SNP rs2808630 and SNP rs3091244. CONCLUSIONS Our study suggests that rs1205 genetic variability in the CRP gene determines the CRP levels in sepsis of different severities, while SNP rs3091244 and SNP rs2808630 are not associated with sepsis. However, the results of the present study on SNP rs1205, rs3091244, and rs2808630 in the CRP gene should be interpreted with caution due to limited sample size and sample heterogeneity. Large-scale, well-designed studies are needed to validate our findings.

Single-stage transanal endorectal pull-through procedure for correction of Hirschsprung disease in neonates and nonneonates: A multicenter study.

PURPOSE: The outcomes of single-stage transanal endorectal pull-through (SSTEPT) for Hirschsprung disease (HSCR) in young patients are favorable; however, reports have shown that diagnosis and surgery at young ages increase the risk for postoperative enterocolitis and slows postoperative recovery. The present study was primarily designed to evaluate the outcomes of SSTEPT in a multi-institutional cohort of neonates and nonneonates with HSCR. METHODS: Between August 2005 and May 2012, a total of 650 children with HSCR were divided into the following two groups: group A (neonatal group, operative age<28days [n=186]); and group B (nonneonatal group, operative age>28days [n=464]). The short-term outcomes were postoperative enterocolitis, perianal excoriation, and anastomotic stricture and leakage rates. The midterm outcomes were incomplete continence and constipation rates based on multi-institutional chart review. Statistical analyses were performed using chi-square (χ2) tests. RESULTS: Follow-up was completed in 112 neonates and 303 nonneonates. Short-term outcomes indicated a higher incidence of perianal excoriation (27.6% vs. 6.6%, χ2=33.70, p<0.05), anastomotic strictures (14.3% vs. 6.0%, χ2=27.18, p<0.05), anastomotic leakage (8.0% vs. 1.7%, χ2=8.36, p<0.05), and postoperative enterocolitis (40.2% vs. 10.2%, χ2=49.05, p<0.05) in group A compared to group B. Midterm outcomes indicated a higher incidence of incomplete continence (35.7% vs. 14.9%, χ2=21.85, p<0.05) in group A compared to group B. CONCLUSION: Performing single-stage transanal endorectal pull-through in the nonneonatal period may be more appropriate than the neonatal period. There were higher rates of perianal excoriation, anastomotic strictures and leakage, postoperative enterocolitis, and incomplete continence postoperatively in neonates than nonneonates.

Histone Arginine Methylation by PRMT7 Controls Germinal Center Formation via Regulating Bcl6 Transcription.

B cells are the center of humoral immunity and produce Abs to protect against foreign Ags. B cell defects lead to diseases such as leukemia and lymphomas. Histone arginine methylation is important for regulating gene activation and silencing in cells. Although the process commonly exists in mammalian cells, its roles in B cells are unknown. To explore the effects of aberrant histone arginine methylation on B cells, we generated mice with a B cell-specific knockout of PRMT7, a member of the methyltransferases that mediate arginine methylation of histones. In this article, we showed that the loss of PRMT7 led to decreased mature marginal zone B cells and increased follicular B cells and promoted germinal center formation after immunization. Furthermore, mice lacking PRMT7 expression in B cells secreted low levels of IgG1 and IgA. Abnormal expression of germinal center genes (i.e., Bcl6, Prdm1, and Irf4) was detected in conditional knockout mice. By overexpressing PRMT7 in the Raji and A20 cell lines derived from B cell lymphomas, we validated the fact that PRMT7 negatively regulated Bcl6 expression. Using chromatin immunoprecipitation-PCR, we found that PRMT7 could recruit H4R3me1 and symmetric H4R3me2 to the Bcl6 promoter. These results provide evidence for the important roles played by PRMT7 in germinal center formation.

[Role and mechanism of heat shock protein 70 in airway hypersecretion].

OBJECTIVE: To explore the role and mechanism of heat shock protein 70 (HSP70) in airway hypersecretion. METHODS: After a stimulation of 8% cigarette smoke extract (CSE), airway cells A549 were treated with HSP70 antibody and c-Jun N-terminal kinase (JNK) specific inhibitor SP600125 respectively. And the cells were divided into 4 groups of blank contrast (serum-free medium), CSE stimulation (8% CSE for 24 h), HSP70 antibody (30-min pre-treatment of HSP70 antibody and culturing in 8% CSE for 24 h) and SP600125 (30-min pre-treatment of SP600125 30 µmol/L and culturing in 8% CSE for 24 h). The relative expression levels of MUC5AC protein in various groups were determined by enzyme-linked immunosorbent assay (ELISA). And the relative transcription level of MUC5AC mRNA was detected by reverse transcription-polymerase chain reaction (PCR) while the synthesized levels of HS70 as well as the phosphorylation levels of JNK and activated protein-1 (mostly c-Jun) were measured by Western blot. RESULTS: As compared with those in blank contrast group (0.26 ± 0.10, 0.28 ± 0.06, 0.30 ± 0.05, 0.30 ± 0.08, 0.36 ± 0.08), HSP70 antibody group (0.30 ± 0.12, 0.29 ± 0.09, 0.34 ± 0.06, 0.47 ± 0.19, 0.39 ± 0.13) and SP600125 group (0.38 ± 0.06, 0.31 ± 0.14, 0.39 ± 0.04, 0.44 ± 0.12, 0.48 ± 0.11), the relative expression levels of MUC5AC protein and mRNA, phosphorylation JNK (p-JNK), c-Jun and p-c-Jun (0.52 ± 0.07, 0.64 ± 0.11, 0.73 ± 0.06, 0.67 ± 0.10, 0.67 ± 0.09) significantly increased in CSE stimulation group (all P < 0.05). And the synthesis levels of HSP70 (0.75 ± 0.09) in CSE stimulation group increased than blank contrast group (0.29 ± 0.03) and HSP70 antibody group (0.40 ± 0.11) (all P < 0.05). CONCLUSION: HSP70 may enhance the expression of MUC5AC in bronchial epithelial A549 cells via a signaling pathway of JNK/AP-1..

Ezrin/Exocyst complex regulates mucin 5AC secretion induced by neutrophil elastase in human airway epithelial cells.

BACKGROUND/AIM: Increased mucin secretion is a characteristic feature of many chronic airway diseases, particularly during periods of exacerbation; however, the exact mechanism of mucin secretion remains unclear. Ezrin, which is a specific marker of apical membranes, is predominantly concentrated in exocyst-rich cell surface structures, crosslinking the actin cytoskeleton with the plasma membrane. In the present study, we examined whether Ezrin is involved in mucin 5AC (MUC5AC) secretion after neutrophil elastase (NE) attack, and we investigated the role of the exocyst complex docking protein Sec3 in this process. METHODS: NE was used as a stimulator in a 16HBE14o- cell culture model. The expression and location of Ezrin and Sec3 were investigated, and the interaction between Ezrin and Sec3 in 16HBE14o-cells was assayed after treatment with NE, Ezrin siRNA, Sec3 siRNA, neomycin or PIP2-Ab. RESULTS: We found that Ezrin was highly expressed in the bronchi of humans with chronic airway diseases. NE induced robust MUC5AC protein secretion. The Ezrin siRNA, Sec3 siRNA, and neomycin treatments led to impaired MUC5AC secretion in cells. Both Ezrin and Sec3 were recruited primarily to the cytoplasmic membrane after NE stimulation, and the neomycin and PIP2-Ab treatments abrogated this effect. Immunoprecipitation analysis revealed that Ezrin and Sec3 combined to form complexes; however, these complexes could not be detected in Ezrin∆1-333 mutant-transfected cells, even when PIP2 was added. CONCLUSIONS: These results demonstrate that Ezrin/Sec3 complexes are essential for MUC5AC secretion in NE-stimulated airway epithelial cells and that PIP2 is of critical importance in the formation of these complexes.

Effects of ATP release on mucin5AC secretion in airway epithelial cells by mechanical stretching.

This study is to determine the effects of ATP and Ca(2+) on mucin5AC (MUC5AC) overexpression in airway epithelial cells in mechanical ventilation. Oxygen was injected into the closed box used in this study to increase the pressure. Gravity-driven draining flow led to formation of a thin liquid film on the upper portion of cell monolayer, exposing cells to the tension forces at the air-liquid interface. The levels of MUC5AC protein and ATP in culture medium were detected by ELISA and high performance liquid chromatography, respectively. Ca(2+) and MUC5AC mRNA in culture cells were detected by flow cytometry and RT-PCR, respectively. Mechanical stretching increased the expression of MUC5AC in cells and the concentration of MUC5AC and ATP in supernatant. BAPTA-AM and EGTA partially reduced the increases in the concentrations of MUC5AC and ATP in supernatant with mechanical ventilation. BAPTA-AM completely inhibited ATP in supernatant with normal breathing conditions. Our results showed that mechanical ventilation increases the secretion of MUC5AC in airway epithelial cells. This is possibly related to Ca(2+)-dependent ATP release and intracellular and external Ca(2+).