NSC48160 targets AMPKα to ameliorate nonalcoholic steatohepatitis by inhibiting lipogenesis and mitochondrial oxidative stress.

Hepatic steatosis, which is triggered by dysregulation of lipid metabolism and redox equilibrium in the liver, is regarded as a risk factor in the non-alcoholic fatty liver disease (NAFLD). However, pharmacologic engagement of this process is difficult. We identified the small molecule NSC48160 as an effective agent against nonalcoholic steatohepatitis (NASH). We found that NSC48160 significantly lowered hepatic lipid levels in vitro and in vivo by activating the AMPKα-dependent pathway. AMPKα regulated its downstream pathway involved in lipogenesis (SREBP-1c/FASN pathway) and fatty acid oxidation (PPARα pathway). Metabonomics analysis combined with RNA-sequencing profiling revealed that NSC48160-induced lipogenesis is modulated by lipid metabolism. Moreover, NSC48160 dramatically reduces reactive oxygen species (ROS) production, restores the levels of the membrane potential and NAD+/NADH ratio, and improves mitochondrial respiration. These findings suggest that NSC48160 is a promising hit compound in the pursuit of a pharmacological approach in the treatment of NASH.

Tetrahydropalmatine ameliorates hepatic steatosis in nonalcoholic fatty liver disease by switching lipid metabolism via AMPK-SREBP-1c-Sirt1 signaling axis.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is becoming a global epidemic without effective treatment currently available. NAFLD is characterized by an increase in hepatic de novo lipogenesis (DNL) and inadequate compensatory enhancement in fatty acid oxidation (FAO), which disturbs lipid homeostasis. In NAFLD, lipid metabolism relies heavily on metabolic reprogramming. Moreover, lipid metabolism plays an essential role in switching between lipogenesis and FAO, which is beneficial for the anti-NAFLD therapy. Our recent study demonstrated that the phytochemical tetrahydropalmatine (THP) has positive efficacy in hepatocellular carcinoma (HCC). However, it remains unclear whether the therapeutic benefits of THP are primarily due to delaying the progression of hepatic steatosis to HCC. PURPOSE: This work aimed to systemically evaluate the pharmacological functions and underlying mechanisms of THP in NAFLD using both in vitro and in vivo models. METHODS: NAFLD models were established using high-fat diet (HFD)-fed mice in vivo and palmitic acid- and oleic acid-challenged hepatocytes in vitro. Metabonomics analysis concomitant with biochemical indices and computational biology assays were performed comprehensively to reveal the key link between the treatment of NAFLD and the AMPK-SREBP-1c-Sirt1 signaling axis. RESULTS: Hepatic metabolomics analysis revealed that THP altered lipid metabolism by enhancing FAO and inhibiting glycolysis, tricarboxylic acid cycle, and urea cycle in HFD-fed mice. Analysis of gene expression showed that THP profoundly suppressed hepatic DNL and promoted FAO. THP supplementation not only significantly decreased body/liver weight gain and serum indices but also ameliorated hepatic steatosis. Simultaneously, impaired lipotoxicity was observed in vivo and in vitro after THP supplementation, protecting against steatosis-driven injury. Metabolic phenotype assays showed that THP promoted switching from glycolysis inhibition to FAO enhancement in steatotic cells, resulting in reprogramming lipid metabolism. Mechanistically, THP accelerated lipid oxidation by activating AMPK-SREBP-1c-Sirt1 axis signaling. Applying molecular docking combined with surface plasmon resonance and cellular thermal shift assay target engagement, as well as siRNA assays, AMPKα was confirmed as a direct molecular target of THP. CONCLUSION: In summary, THP ameliorates hepatic steatosis in NAFLD by switching lipid metabolism via the AMPK-SREBP-1c-Sirt1 pathway. This work provides an attractive phytochemical component for therapy against hepatic steatosis in NAFLD.

Advances in the Diagnosis and Treatment of Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease that affects approximately one-quarter of the global adult population, posing a significant threat to human health with wide-ranging social and economic implications. The main characteristic of NAFLD is considered that the excessive fat is accumulated and deposited in hepatocytes without excess alcohol intake or some other pathological causes. NAFLD is a progressive disease, ranging from steatosis to non-alcoholic steatohepatitis (NASH), cirrhosis, hepatocellular carcinoma, liver transplantation, and death. Therefore, NAFLD will probably emerge as the leading cause of end-stage liver disease in the coming decades. Unlike other highly prevalent diseases, NAFLD has received little attention from the global public health community. Liver biopsy is currently considered the gold standard for the diagnosis and staging of NAFLD because of the absence of noninvasive and specific biomarkers. Due to the complex pathophysiological mechanisms of NAFLD and the heterogeneity of the disease phenotype, no specific pharmacological therapies have been approved for NAFLD at present, although several drugs are in advanced stages of development. This review summarizes the current evidence on the pathogenesis, diagnosis and treatment of NAFLD.

Phytochemical gallic acid alleviates nonalcoholic fatty liver disease via AMPK-ACC-PPARa axis through dual regulation of lipid metabolism and mitochondrial function.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) usually includes NAFL called simple hepatosteatosis and nonalcoholic steatohepatitis (NASH) called more steatohepatitis. The latter is a leading pathogenic promotor of hepatocellular carcinoma (HCC). Phytochemical gallic acid (GA) has been proved to exert positive efficacy in HCC in our work, but it remains unclear whether its hepatoprotective effect attributes to the controlled transition from simple steatosis to steatohepatitis. PURPOSE: This work aims to provide mechanistic evidence that the therapeutic application of GA in NAFLD is indispensable for GA-meliorated NASH progression. METHODS: The high-fat diet (HFD)-fed mice and palmitic acid (PA) and oleic acid (OA)-treated hepatocytes were used collectively in this study. Bioinformatic analysis, clinical subjects, RNA-Seq, molecular docking, and confirmatory experiments were performed comprehensively to uncover the pathological link between the AMPK-ACC-PPARα axis and the treatment of NAFLD. RESULTS: By analyzing the clinical subjects and GEO database, we find a close link between the activation of AMPK-ACC-PPARα axis and the progression of NAFLD in human fatty liver. Subsequent assays show that GA exhibits pharmacological activation of AMPK, reprogramming lipid metabolism, and reversing mitochondrial function in cellular and murine fatty liver models. AMPK activation conferred substantial protection against murine NASH and fibrosis in the context of HFD-induced NAFLD. In contrast, silencing AMPK badly aggravates lipid deposition in hepatocytes, boosting NASH and NAFLD-associated HCC progression. The in silico docking, in vitro surface plasmon resonance and in vivo cellular thermal shift assay collectively reveal that GA directly interacts with AMPKα, which inactivates the ACC-PPARα axis signaling. Notably, GA repairs the liver damage, lipotoxicity, and mitochondrial respiratory capacity caused by excessive mtROS, while showing minimal effects in other major organs in mice. CONCLUSION: Our work identifies GA as an important suppressor of NAFLD-HCC progression, and underscores the AMPK-ACC-PPARα signal axis as a potential therapeutic target for NAFLD treatment.

Emerging Potential Mechanism and Therapeutic Target of Ferroptosis in PDAC: A Promising Future.

Pancreatic cancer (PC) is a devastating malignant tumor of gastrointestinal (GI) tumors characterized by late diagnosis, low treatment success and poor prognosis. The most common pathological type of PC is pancreatic ductal adenocarcinoma (PDAC), which accounts for approximately 95% of PC. PDAC is primarily driven by the Kirsten rat sarcoma virus (KRAS) oncogene. Ferroptosis was originally described as ras-dependent cell death but is now defined as a regulated cell death caused by iron accumulation and lipid peroxidation. Recent studies have revealed that ferroptosis plays an important role in the development and therapeutic response of tumors, especially PDAC. As the non-apoptotic cell death, ferroptosis may minimize the emergence of drug resistance for clinical trials of PDAC. This article reviews what has been learned in recent years about the mechanisms of ferroptosis in PDAC, introduces the association between ferroptosis and the KRAS target, and summarizes several potential strategies that are capable of triggering ferroptosis to suppress PDAC progression.

Non-Alcoholic Fatty Liver Disease (NAFLD) Pathogenesis and Natural Products for Prevention and Treatment.

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease, affecting approximately one-quarter of the global population, and has become a world public health issue. NAFLD is a clinicopathological syndrome characterized by hepatic steatosis, excluding ethanol and other definite liver damage factors. Recent studies have shown that the development of NAFLD is associated with lipid accumulation, oxidative stress, endoplasmic reticulum stress, and lipotoxicity. A range of natural products have been reported as regulators of NAFLD in vivo and in vitro. This paper reviews the pathogenesis of NAFLD and some natural products that have been shown to have therapeutic effects on NAFLD. Our work shows that natural products can be a potential therapeutic option for NAFLD.

What are the predictive factors of body image disturbance in patients with systemic lupus erythematosus? A cross-sectional study in China.

OBJECTIVES: Patients with systemic lupus erythematosus (SLE) may experience body image disorders, which can adversely affect their physical and mental health. We aimed to assess the body-image-related quality of life of patients with SLE, explore the influencing factors and determine the potential predictors of body image disturbance (BID) in these patients. DESIGN: Cross-sectional study. SETTING: The department of rheumatology and immunology in Nantong. PARTICIPANTS: A convenience sample of 230 patients with SLE. INTERVENTIONS: The study survey included an assessment of demographic information and evaluations using the Body Image Disturbance questionnaire (BIDQ), Hospital Anxiety and Depression Scale, Multidimensional Fatigue Inventory-20 and Body Image Quality of Life Inventory (BIQLI). PRIMARY AND SECONDARY OUTCOME MEASURES: BID scores and their possible predictors. Data were analysed using descriptive statistics, correlational analysis and stepwise multiple linear regression analysis. RESULTS: The mean BIDQ score and the mean scores for anxiety, depression and fatigue were 23.04 (SD, SD=11.90), 6.94 (SD=4.53), 6.49 (SD=4.51) and 54.21 (SD=11.63), respectively. The mean BIQLI score was 0.31 (SD=16.59). The findings revealed significant correlations with education level, comorbidities, SLE Disease Activity Index (SLEDAI), anxiety, depression, fatigue and BIQLI. Fatigue, depression, presence of comorbidities and SLEDAI were predictors of worsening BID (p<0.05). CONCLUSION: In our study, the relationship between BIDQ and anxiety, depression, and fatigue was analysed, and predictors of BID were defined. When formulating interventional measures, the patient's condition should be evaluated, and effective interventions should be implemented to improve the patient's body image and ultimately improve the patient's quality of life.

Targeting KRAS in PDAC: A New Way to Cure It?

Pancreatic cancer is one of the most intractable malignant tumors worldwide, and is known for its refractory nature and poor prognosis. The fatality rate of pancreatic cancer can reach over 90%. In pancreatic ductal carcinoma (PDAC), the most common subtype of pancreatic cancer, KRAS is the most predominant mutated gene (more than 80%). In recent decades, KRAS proteins have maintained the reputation of being "undruggable" due to their special molecular structures and biological characteristics, making therapy targeting downstream genes challenging. Fortunately, the heavy rampart formed by KRAS has been broken down in recent years by the advent of KRASG12C inhibitors; the covalent inhibitors bond to the switch-II pocket of the KRASG12C protein. The KRASG12C inhibitor sotorasib has been received by the FDA for the treatment of patients suffering from KRASG12C-driven cancers. Meanwhile, researchers have paid close attention to the development of inhibitors for other KRAS mutations. Due to the high incidence of PDAC, developing KRASG12D/V inhibitors has become the focus of attention. Here, we review the clinical status of PDAC and recent research progress in targeting KRASG12D/V and discuss the potential applications.

A Study Protocol for the Management of Children With Juvenile Idiopathic Arthritis Based on ePROs.

Background: Juvenile idiopathic arthritis (JIA) is a common chronic rheumatic disease with no known cures, affecting children with the age of onset under 16 years. Patient-reported outcome (PRO) measures are an important basis for evaluating the impact of JIA and associated therapies, however, which is particular challenge in the pediatric setting. At present, no randomized controlled studies have investigated the effect and usability of ePROs symptom management for children with JIA. Methods: This longitudinal, randomized, controlled trial will be carried out at outpatient and pediatric wards of the Shanghai Children's Medical Center affiliated to Shanghai Jiao Tong University School of Medicine. A total of one hundred children with JIA diagnosed according to the International League of Associations for Rheumatology (ILAR) patients are randomized to receive individualized symptom management based on ePROs or routine management. The primary outcome is the mean C-Ped-PROMIS T-scores of patients in the ePROs-based group and the control group. The secondary outcomes are the trajectories of C-Ped-PROMIS T-scores and HRQOL scores, and changing relationship between them. Data were collected at 5 time points: at enrollment ("baseline") and at the time of follow-up visits scheduled at 1, 3, 6, and 12 months. Discussion: The findings are expected to conclude that the symptom management based on ePROs for children with JIA can improve the symptom of JIA, and it is a feasible and effective way to monitor and intervene children with JIA. Clinical Trial: http://www.chictr.org.cn/showproj.aspx?proj=132769; (ChiCTR2100050503).

Combined Levo-tetrahydropalmatine and diphenyleneiodonium chloride enhances antitumor activity in hepatocellular carcinoma.

Metabolic dysregulation is a hallmark of hepatocellular carcinoma (HCC). AMPK is a crucial hub of metabolic regulation during cancer progression. We show that phytochemical Levo-tetrahydropalmatine (THP) activates AMPK-dependent autophagy to downregulate the mitochondrial respiration and glycolysis. Consequently, THP significantly decreased cell viability in two HCC cell lines, BEL-7402 and SMMC-7721. Similarly, NOX4 inhibitor diphenyleneiodonium chloride (DPI) induces concomitant downregulation of the mitochondrial and glycolytic metabolism. In contrast to THP, cells are less sensitive to proliferation inhibition induced by DPI treatment as compared to THP treatment did. Combined treatment of THP and DPI was found to be more efficacious in killing cancer cells than either of the agents treated individually. Indeed, the co-operative effect by the THP-DPI combination improves the pro-apoptotic activity in response to the energy depletion as outlined by a drastic decrease in ATP levels. Therapeutic regime significantly reduced the tumor growth in mice. Importantly, this is realized without causing systemic toxicity to other organs. Collectively, our work shows that the combinatorial therapy of autophagy activator THP and NOX4 inhibitor DPI may be considered as a therapeutic avenue against HCC.

[Levo-tetrahydropalmatine promotes apoptosis of human hepatocellular carcinoma through switching energy metabolism phenotype via upregulation of mitochondrial reactive oxygen species].

Mitochondrion is an important organelle that maintains cellular homeostasis and plays a crucial role in determining cell fate. The present study investigated the effect of levo-tetrahydropalmatine(THP) on autophagic flux and energy metabolism phenotype of human hepatocellular carcinoma(HCC) SMMC-7721 and BEL-7402 cells. SMMC-7721 and BEL-7402 cells were treated with THP(100 µmol·L~(-1)) with or without N-acetyl-L-cysteine(NAC, 10 µmol·L~(-1)) for 24 h. The mitochondrial reactive oxygen species(mtROS) was detected by flow cytometry(FCM) with MitoSOX probe and fluorescence microscopy, respectively. Thereafter, autophagic flux was detected by FCM with CYTO-ID probe, and the protein levels of microtubule-associated protein 1 A/1 B-light chain 3-Ⅰ(LC3Ⅰ), LC3Ⅱ, and phosphorylated AMP-activated protein kinase(p-AMPK)/AMPK were measured by Western blot. Mitochondrial respiration was examined by Seahorse XFp assay and cell proliferation by a system. Annexin V-FITC and PI/RNase staining was employed to detect apoptosis of SMMC-7721 and BEL-7402 cells treated with THP and/or NAC. Subsequently, membrane potential was measured with MitoTracker Red CMXRos. Compared with the control group, THP promoted mtROS production and THP combined with NAC attenuated the autophagic flux increase induced by THP alone in SMMC-7721 and BEL-7402 cells. When cells were co-treated with THP and chloroquine(CQ, an autophagy inhibitor), THP further increased mtROS and apoptosis. In addition, THP significantly reduced mitochondrial respiration in terms of mitochondrial basal respiration, ATP production, and maximal respiration. Meanwhile, THP significantly reduced the proliferation index and mitochondrial membrane potential of HCC cells accompanied by the increased apoptosis. This study demonstrates that the up-regulation of mtROS by THP significantly promotes HCC cell autophagy(protective autophagy) and impairs mitochondrial respiration through reprogramming energy metabolism, ultimately inducing the mitochondria-mediated apoptosis of SMMC-7721 and BEL-7402 cells.

AMPK-Mediated Metabolic Switching Is High Effective for Phytochemical Levo-Tetrahydropalmatine (l-THP) to Reduce Hepatocellular Carcinoma Tumor Growth.

Targeting cancer cell metabolism has been an attractive approach for cancer treatment. However, the role of metabolic alternation in cancer is still unknown whether it functions as a tumor promoter or suppressor. Applying the cancer gene-metabolism integrative network model, we predict adenosine monophosphate-activated protein kinase (AMPK) to function as a central hub of metabolic landscape switching in specific liver cancer subtypes. For the first time, we demonstrate that the phytochemical levo-tetrahydropalmatine (l-THP), a Corydalis yanhusuo-derived clinical drug, as an AMPK activator via autophagy-mediated metabolic switching could kill the hepatocellular carcinoma HepG2 cells. Mechanistically, l-THP promotes the autophagic response by activating the AMPK-mTOR-ULK1 and the ROS-JNK-ATG cascades and impairing the ERK/AKT signaling. All these processes ultimately synergize to induce the decreased mitochondrial oxidative phosphorylation (OXPHOS) and mitochondrial damage. Notably, silencing AMPK significantly inhibits the autophagic flux and recovers the decreased OXPHOS metabolism, which results in HepG2 resistance to l-THP treatment. More importantly, l-THP potently reduces the growth of xenograft HepG2 tumor in nude mice without affecting other organs. From this perspective, our findings support the conclusion that metabolic change is an alternative approach to influence the development of HCC.

Physics of biomolecular recognition and conformational dynamics.

Biomolecular recognition usually leads to the formation of binding complexes, often accompanied by large-scale conformational changes. This process is fundamental to biological functions at the molecular and cellular levels. Uncovering the physical mechanisms of biomolecular recognition and quantifying the key biomolecular interactions are vital to understand these functions. The recently developed energy landscape theory has been successful in quantifying recognition processes and revealing the underlying mechanisms. Recent studies have shown that in addition to affinity, specificity is also crucial for biomolecular recognition. The proposed physical concept of intrinsic specificity based on the underlying energy landscape theory provides a practical way to quantify the specificity. Optimization of affinity and specificity can be adopted as a principle to guide the evolution and design of molecular recognition. This approach can also be used in practice for drug discovery using multidimensional screening to identify lead compounds. The energy landscape topography of molecular recognition is important for revealing the underlying flexible binding or binding-folding mechanisms. In this review, we first introduce the energy landscape theory for molecular recognition and then address four critical issues related to biomolecular recognition and conformational dynamics: (1) specificity quantification of molecular recognition; (2) evolution and design in molecular recognition; (3) flexible molecular recognition; (4) chromosome structural dynamics. The results described here and the discussions of the insights gained from the energy landscape topography can provide valuable guidance for further computational and experimental investigations of biomolecular recognition and conformational dynamics.

Epigallocatechin gallate (EGCG) attenuates staphylococcal alpha-hemolysin (Hla)-induced NLRP3 inflammasome activation via ROS-MAPK pathways and EGCG-Hla interactions.

Alpha-hemolysin (Hla), the virulence factor secreted by Staphylococcus aureus (S. aureus), plays a critical role in infection and inflammation, which is a severe health burden worldwide. Therefore, it is necessary to develop a drug against Hla. Epigallocatechin gallate (EGCG), a polyphenol extracted from green tea, has excellent anti-inflammatory activity. In this study, we investigated the inhibitory effect of EGCG on Hla-induced NLRP3 inflammasome activation in vitro and in vivo and elucidated the potential molecular mechanism. We found that EGCG attenuated the hemolysis of Hla by inhibiting its secretion. Besides, EGCG significantly decreased overproduction of ROS and activation of MAPK signaling pathway induced by Hla, thereby markedly attenuating the expression of NLRP3 inflammasome-related proteins in THP-1 cells. Notably, EGCG could spontaneously bind to Hla with affinity constant of 1.71 × 10-4 M, thus blocking the formation of the Hla heptamer. Moreover, Hla-induced expression of NLRP3, ASC and caspase-1 protein and generation of IL-1ß and IL-18 in the damaged liver tissue of mice were also significantly suppressed by EGCG in a dose-dependent manner. Collectively, EGCG could be a promising candidate for alleviating Hla-induced the activation of NLRP3 inflammasome, depending on ROS mediated MAPK signaling pathway, and inhibition of Hla secretion and heptamer formation. These findings will enlighten the applications of EGCG to reduce the S. aureus infection by targeting Hla in food and related pharmaceutical fields.

Discovery of Small Molecule NSC290956 as a Therapeutic Agent for KRas Mutant Non-Small-Cell Lung Cancer.

HRas-GTP has a transient intermediate state with a "non-signaling open conformation" in GTP hydrolysis and nucleotide exchange. Due to the same hydrolysis process and the structural homology, it can be speculated that the active KRas adopts the same characteristics with the "open conformation." This implies that agents locking this "open conformation" may theoretically block KRas-dependent signaling. Applying our specificity-affinity drug screening approach, NSC290956 was chosen by high affinity and specificity interaction with the "open conformation" structure HRasG60A-GppNp. In mutant KRas-driven non-small-cell lung cancer (NSCLC) model system, NSC290956 effectively suppresses the KRas-GTP state and gives pharmacological KRas inhibition with concomitant blockages of both the MAPK-ERK and AKT-mTOR pathways. The dual inhibitory effects lead to the metabolic phenotype switching from glycolysis to mitochondrial metabolism, which promotes the cancer cell death. In the xenograft model, NSC290956 significantly reduces H358 tumor growth in nude mice by mechanisms similar to those observed in the cells. Our work indicates that NSC290956 can be a promising agent for the mutant KRas-driven NSCLC therapy.

Subinhibitory concentrations of Honokiol reduce α-Hemolysin (Hla) secretion by Staphylococcus aureus and the Hla-induced inflammatory response by inactivating the NLRP3 inflammasome.

Staphylococcus aureus (S. aureus) is one of the most serious human pathogens. α-Hemolysin (Hla) secreted by S. aureus is a key toxin for various infections. We herein report that Honokiol, a natural plant polyphenol, inhibits the secretion and hemolytic activity of staphylococcal Hla with concomitant growth inhibition of S. aureus and protection of S. aureus-mediated cell injury within subinhibitory concentrations. In parallel, Honokiol attenuates the staphylococcal Hla-induced inflammatory response by inhibiting NLRP3 inflammasome activation in vitro and in vivo. Consequently, the biologically active forms of the inflammatory cytokines IL-1ß and IL-18 are reduced significantly in response to Honokiol in mice infected with S. aureus. Experimentally, we confirm that Honokiol binds to monomeric Hla with a modest affinity without impairing its oligomerization. Based on molecular docking analyses in silico, we make a theoretical discovery that Honokiol is located outside of the triangular region of monomeric Hla. The binding model restricts the function of the residues related to membrane channel formation, which leads to the functional disruption of the assembled membrane channel. This research creates a new paradigm for developing therapeutic agents against staphylococcal Hla-mediated infections.

The sedation practices of paediatric intensive care unit nurses and the influencing factors in China.

Nurses play a key role in administering sedation to mechanically ventilated children, which impacts children's psychological, physiological and cognitive changes in the paediatric intensive care unit. This study aimed to survey the sedation practices of paediatric intensive care unit nurses on mechanically ventilated children in China and explored the influencing factors. A cross-sectional survey was conducted based on electronic questionnaires comprised of the Nurse Sedation Practices Scale (Chinese version) in 14 different types of paediatric intensive care units of 11 academic hospitals in China from 15 February to 15 April 2017. A convenience sample of 495 nurses [73·4% response rate, (674)] completed the survey. Seven units applied Ramsay Sedation Scale as a sedative assessment tool. The majority of the nurses used observed behaviours and physiological changes of the ventilated children as indicators to assess the sedation level, and they had a positive attitude and intention, which may influence practice positively, whereas high clinical workload and the lack of communication between the nurses and families might hinder practice. The practice of sedation varied greatly in different regions, and the respondents of the northwest region scored lower. Paediatric nurses in China rarely used a validated paediatric instrument to assess sedation, and most nurses relied on physiological and behavioural cues. The quality of sedation training, nursing workload and regional economic disparity affected the sedation practice. The restricted visiting policy and lack of clearly defined nursing responsibilities around sedation may hinder effective sedation assessment and management. This study found that there was no paediatric-validated tool popularized in paediatric intensive care units in China and explored influencing factors. We suggest that a validated tool, high-quality training and hospital's policy, such as visiting regulation, should be promoted to improve the sedation practice.

A child diagnosed with rigid spine syndrome complicated by ventilatory disorders: a nursing case report.

Rigid spine syndrome is a rare myopathy in children and has a poor prognosis because of its lack of treatment and eventual ventilatory failure. We report the case of a 10-year-old child with RSS and ventilatory disorders. We provided care to the child using bilevel positive airway pressure (BiPAP) non-invasive mechanical ventilation and continuous monitoring of transcutaneous carbon dioxide pressure. A 10-year-old Han Chinese girl presented (6 April 6 2016) to the Shanghai Children's Medical Center with ventilatory disorders, including hypoxia and hypercapnia. Transcutaneous oxygen saturation with mask oxygen inspiration was 90%. BiPAP non-invasive ventilator-assisted ventilation was continuously used. Through continuous non-invasive ventilation and carbon dioxide monitoring, the symptoms of dyspnea in this child were effectively controlled and improved. She was discharged on April 19 with instructions to continue using BiPAP at home and transcutaneous oxygen saturation was maintained at 94% to 98%. This case highlights that nursing of patients with rigid spine syndrome and ventilatory disorders should focus on evaluating the effect of non-invasive mechanical ventilation, prevention of complications, and continuous nursing after discharge. Additionally, continuous monitoring of transcutaneous carbon dioxide pressure is feasible for evaluating the effect of BiPAP.

Phenotype and RNA-seq-Based transcriptome profiling of Staphylococcus aureus biofilms in response to tea tree oil.

Staphylococcus aureus (S. aureus) is a Gram-positive bacterium that causes a wide range of diseases, including food poisoning. Tea tree oil (TTO), an essential oil distilled from Melaleuca alternifolia, is well-known for its antibacterial activities. TTO effectively inhibited all 19 tested strains of S. aureus biofilm and planktonic cells. Phenotype analyses of S. aureus biofilm cells exposed to TTO were performed by biofilm adhesion assays, eDNA detection and PIA release. RNA sequencing (RNA-seq) was used in our study to elucidate the mechanism of TTO as a potential antibacterial agent to evaluate differentially expressed genes (DEGs) and the functional network in S. aureus ATCC 29213 biofilms. TTO significantly changed (greater than a 2- or less than a 2-fold change) the expression of 304 genes in S. aureus contained in biofilms. The levels of genes related to the glycine, serine and threonine metabolism pathway, purine metabolism pathway, pyrimidine metabolism pathway and amino acid biosynthesis pathway were dramatically changed in the biofilm exposed to TTO. Furthermore, the expression changes identified by RNA-seq analysis were verified by real-time RT-PCR. To the best of our knowledge, this research is the first study to report the phenotype and expression profiles of S. aureus in biofilms exposed to TTO.

Antibacterial activity and mode of action of ε-polylysine against Escherichia coli O157:H7.

Purpose. Gram-negative Escherichia coli O157:H7 were chosen as model bacteria to evaluate the antimicrobial mechanism of ε-polylysine (ε-PL).Methodology. The antibacterial activity of ε-PL was detected by measuring the minimum inhibitory concentration values as well as the time-kill curve. The membrane integrity was determined by ultraviolet (UV) absorption, membrane potential (MP) assay and flow cytometry (FCM) experiments. The permeability of the inner membrane was detected by ß-galactosidase activity assay. Furthermore, electron microscopy [scanning electron microscopy (SEM) and transmission electron microscopy (TEM)] was utilized to observe bacterial morphology.Key findings. These results demonstrated that ε-PL showed its antibacterial activity by changing the integrity and permeability of cell membranes, leading to rapid cell death. The electron microscopy analysis (SEM and TEM) results indicated that the bacterial cell morphology, membrane integrity and permeability were spoiled when the E. coli O157:H7 cells were exposed to minimum inhibitory concentrations of ε-PL (16 µg ml-1). In addition, the bacterial membrane was damaged more severely when the concentration of ε-PL was increased.Conclusion. The present study investigated the antimicrobial mechanism of ε-PL by measuring the content of cytoplasmic ß-galactosidase, proteins and DNA. In addition, SEM and TEM were carried out to assess the mechanism. These results show that ε-PL has the ability to decrease the content of large molecules, cellular soluble proteins and nucleic acids associated with increasing the content of cytoplasmic ß-galactosidase in supernatant by causing damage to the cell membranes. Consequently, the use of ε-PL as a natural antimicrobial agent should eventually become an appealing method in the field of food preservation.