Human neutrophil peptide 1 promotes immune sterilization in vivo by reducing the virulence of multidrug-resistant Klebsiella pneumoniae and increasing the ability of macrophages.

By studying the expression in patients and cell modeling in vitro, antimicrobial peptides for Klebsiella were screened. Killing curve and membrane permeability experiments are used to study the antibacterial effect of antimicrobial peptides in vitro. Cytotoxicity-related indicators including lipopolysaccharide (LPS), capsule polysaccharide (CPS), and outer membrane protein expression were measured. Intranasal inoculation of pneumoconiosis was used to construct a mouse infection model, and the survival rate and cytokine expression level were tested. Human neutrophil peptide 1 (HNP-1) showed a significant antibacterial effect, which improved the permeability of the outer membrane of K. pneumoniae. Moreover, HNP-1 decreased LPS, CPS content, and outer membrane proteins. K. pneumoniae infection decreased antimicrobial peptide, oxidative stress, and autophagy-related genes, while HNP-1 increased these genes. After coculture with macrophages, the endocytosis of macrophages is enhanced and the bacterial load is greater in the K. pneumoniae + peptide group. Besides, higher levels of pp38 and pp65 in the K. pneumoniae + peptide group. HNP-1 rescued the cytotoxicity induced by K. pneumoniae. The survival rate is significantly improved after K. pneumoniae is treated by HNP-1. All cytokines in the peptide group were significantly higher. HNP-1 promotes immune sterilization by reducing the virulence of multidrug-resistant K. pneumoniae and increasing the ability of macrophages.

Application of Non-invasive Positive Pressure Ventilation Combined with PetCO2 Monitoring for Patients with Chronic Obstructive Pulmonary Disease Combined with Severe Respiratory Failure.

OBJECTIVE: To investigate the role of PetCO2 monitoring in non-invasive positive pressure ventilation (NPPV) treatment for chronic obstructive pulmonary disease (COPD) patients combined with severe respiratory failure. STUDY DESIGN: A clinical retrospective study. PLACE AND DURATION OF STUDY: The ICU Emergency Department, Wuxi Second People's Hospital, Wuxi, China, from February 2015 to February 2016. METHODOLOGY: A total of 60 COPD patients with respiratory failure were selected. All patients received non-invasive positive pressure ventilation and conventional treatment. PetCO2 values were recorded two hours before and after NPPV treatment. At the same time, blood was collected for arterial blood gas analysis. Changes in PetCO2, PaCO2 and the difference between PaCO2 and PetCO2 (Pa-etCO2) were also monitored to determine the correlation between PetCO2 and PaCO2. RESULTS: After two hours of initial NPPV treatment, among the 60 patients, the PaCO2 and Pa-etCO2 of 40 patients were significantly decreased (66.7%), the PaCO2 and Pa-etCO2 of 20 patients were not significantly decreased (33.3%). The correlation analysis revealed that PaCO2 and PetCO2 were negatively correlated (correlation coefficient r = -0.537, p=0.001, p<0.001). Furthermore, there were no significant correlations between PaCO2 and PetCO2 in the ineffective group (correlation coefficient r = -0.253, p=0.116, p>0.05). CONCLUSION: PaCO2 monitoring could not be replaced by PetCO2 monitoring for patients with COPD combined with severe respiratory failure. Nevertheless, dynamic monitoring can instantly feedback the respiration state, which can guide the respiration, and improve the success rate of NPPV treatment and prognosis.

Resveratrol protects the loss of connexin 43 induced by ethanol exposure in neonatal mouse cardiomyocytes.

Excessive alcohol consumption provides risk to cardiomyopathy with unknown mechanisms. Resveratrol, a plant polyphenol, is widely reported for its cardiovascular benefits, while its effect on alcohol-induced impairments in cardiomyocytes largely remains unknown. Effects of resveratrol on the cardiomyocytes under ethanol insult were studied in vitro. Ethanol exposure in mouse neonatal cardiomyocytes increased cell death and induced a specific loss of tight junction protein, connexin 43. In spite of adverse effects at higher concentrations, resveratrol at 10 µM improved cell viability of cardiomyocytes in the presence of a deleterious dose of ethanol. Importantly, the co-treatment of resveratrol with ethanol exhibited the restoration of connexin 43 protein. Further assays showed that these effects were likely associated with the antioxidative actions of resveratrol, and correlated with the alleviation of MAP kinase activation in cultured cardiomyocytes in response to ethanol. Our data suggests a novel mechanism of cardiomyocyte cell loss under ethanol exposure and provides new evidence of protective effects of resveratrol in the cardiomyocytes.

[The changes in insulin sensitivity under stress and its clinical significance in the critically ill patients].

OBJECTIVE: To observe the changes in blood glucose, serum insulin level and insulin resistance of critically ill patients during the acute stage and explore the relationship between the changes and their prognosis. METHODS: Fifty-four patients in intensive care unit (ICU) were enrolled. All the patients were assessed with acute physiology and chronic health evaluation II (APACHE II) scores in 24 hours after admission. Fasting blood glucose (FBG) and fasting insulin (FINS) were determined within 24 hours or the next morning, and then insulin resistance was evaluated by insulin sensitivity index (ISI). According to the APACHE II scores, the severity and prognosis, the patients were stratified into groups respectively. The difference in APACHE II scores, FBG, FINS and ISI among groups were analyzed. Furthermore, the correlation between APACHE II score and FBG, FINS, ISI were studied respectively. RESULTS: Based on APACHE II scores, the patients were divided into group A (APACHE II scoresor=21). The levels of FBG and FINS were found to be elevated with the increase in APACHE II score, and in contrast ISI greatly reduced (P<0.05 or P<0.01). APACHE II scores, FBG and FINS in multiple organ dysfunctions group were significantly higher than in single organ dysfunction group, and ISI was found to be significantly decreased (P<0.05 or P<0.01). Additionally, APACHE II scores and FBG in non-survivor group were obviously higher than those in survivor group, while ISI was markedly lower (all P<0.01), but no difference in FINS levels was found between the two groups. In the 54 critically ill patients, correlation study showed that significant positive correlation was found between FBG and APACHE II score (r=0.816 5, P<0.01, regression equation : y=0.573x+3.072) and significant negative correlation between ISI and APACHE II score (r=-0.703 9, P<0.01, regression equation : y=-0.107x-3.598), but no linear correlation was found between APACHE II score and FINS (r=0.283 0, P>0.05). CONCLUSION: The study suggests that FBG and ISI could be used to evaluate the severity and prognosis. Hyperinsulinemia is found in some critically ill patients, but FINS is not helpful for assessing the severity and outcome.