Cannabinoid receptor 2 alleviates sepsis-associated acute lung injury by modulating maturation of dendritic cells.

BACKGROUND: Dendritic cells (DCs) play a key role in a variety of inflammatory lung diseases, but their role in sepsis-associated acute lung injury (SA-ALI) is currently not been illuminated. Cannabinoid receptor 2 (CNR2) has been reported to regulate the DCs maturation. However, whether the CNR2 in DCs contributes to therapeutic therapy for SA-ALI remain unclear. In current study, the role of CNR2 on DCs maturation and inflammatory during SA-ALI is to explored. METHODS: First, the CNR2 level was analyzed in isolated Peripheral Blood Mononuclear Cells (PBMCs) and Bronchoalveolar Lavage Fluid (BALF) from patient with SA-ALI by qRT-PCR and flow cytometry. Subsequently, HU308, a specific agonist of CNR2, and SR144528, a specific antagonist of CNR2, were introduced to explore the function of CNR2 on DCs maturation and inflammatory during SA-ALI. Finally, CNR2 conditional knockout mice were generated to further confirm the function of DCs maturation and Inflammation during SA-ALI. RESULTS: First, we found that the expression of CNR2 on DCs was decreased in patient with SA-ALI. Besides, the result showed HU308 could decrease the maturation of DCs and the level of inflammatory cytokines, simultaneously reduce pulmonary pathological injury after LPS-induced sepsis in mice. In contrast of HU308, SR144528 exhibits opposite function of DCs maturate, inflammatory cytokines and lung pathological injury. Furthermore, comparing with SR144528 treatment, similar results were obtained in DCs specific CNR2 knockout mice after LPS treatment. CONCLUSION: CNR2 could alleviate SA-ALI by modulating maturation of DCs and inflammatory factors levels. Targeting CNR2 signaling specifically in DCs has therapeutic potential for the treatment of SA-ALI.

Exosomal miR-127-5p from BMSCs alleviated sepsis-related acute lung injury by inhibiting neutrophil extracellular trap formation.

Neutrophil extracellular traps (NETs) play an important role in sepsis-related acute lung injury (ALI). Bone marrow mesenchymal stem cells (BMSCs)-derived exosomes and miRNA are becoming promising agents for the treatment of ALI. The current study aimed to elucidate the mechanism by BMSCs-derived exosomes carrying miR-127-5p inhibiting to the formation of NETs in sepsis-related ALI. We successfully isolated exosomes from BMSCs and confirmed that miR-127-5p was enriched in the exosomes. ALI mice treated with BMSCs-derived exosomes histologically improved, and the release of NETs and inflammatory factors in lung tissue and peripheral blood of mice also decreased compared with LPS group, while the protective effect of exosomes was attenuated after the knockdown of miR-127-5p. Using dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay, we identified CD64 as a direct target of miR-127-5p. Meanwhile, BMSCs-derived exosomes can synergize with anti-CD64 mab in ALI mice to reduce tissue damage, inhibit the release of inflammatory factors and NETs formation. The synergistic effect of exosomes was attenuated when miR-127-5p was down-regulated. These findings suggest that exosomal miR-127-5p derived from BMSCs is a potential therapeutic agent for treatment of sepsis-induced ALI through reducing NETs formation by targeting CD64.

TFAM-Mediated mitochondrial transfer of MSCs improved the permeability barrier in sepsis-associated acute lung injury.

Vascular endothelial cell barrier disruption is a hallmark of sepsis-induced acute lung injury (ALI). Mesenchymal stem cells (MSCs)-based therapy has been regarded as a promising treatment for repairing injured lungs, and mitochondrial transfer was shown to be important for the therapeutic effects of MSCs. Here we investigated the ability of MSCs to modulate endothelial barrier integrity through mitochondrial transfer in sepsis-induced ALI. We found that mitochondrial transfer from MSCs to LPS-induced PMVECs through forming tunneling nanotubes (TNTs). Due to the inhibition of TNTs (using LAT-A), MSCs-mediated reparation on PMVECs functions, including cell apoptosis, MMP, ATP generation, TEER level and monolayer permeability of FITC-dextran were greatly inhibited. In addition, silencing of mitochondrial transcription factor A (TFAM) in MSCs could also partly inhibit the TNTs formation and aggravate the LPS-induced mitochondrial dysfunction and permeability barrier in PMVECs. Furthermore, the LPS-induced pulmonary edema and higher pulmonary vascular permeability were alleviated by MSCs while that of lung tissue bounced back after MSCs were pre-incubated by LAT-A and or down-regulation of TFAM. Therefore, we firstly revealed that regulation of TFAM expression in MSCs played a critical role to improve the permeability barrier of PMVECs by TNTs mediating mitochondrial transfer in sepsis-associated ALI. This study provided a new therapeutic strategy for the treatment of sepsis-induced ALI.

A Novel Combination of Keratinocyte and Autologous Microskin Grafting to Repair Full-Thickness Skin Loss.

INTRODUCTION: The high mortality of patients with extensive deep burns is mainly attributed to the extensive burn wound and the scarce autologous skin left for wound repair. The purpose of this study was to explore how to effectively use the limited remaining autologous skin to repair the extensive deep wound. METHODS: Human keratinocytes harvested from the foreskin were cultured and transfected with epidermal growth factors (EGFs) by an adenovirus vector (Ad-EGF). The expression and the biological activity of EGF in both the normal human keratinocytes and the EGF gene-modified human keratinocytes were quantified by ELISA assay and CCK-8 assay, respectively. The differentiated phenotype of epidermal cells was detected by immunofluorescence staining via CK10, CK14, and CK19 expressions. Rats were subjected to a full-thickness skin loss (3.3 cm × 3.0 cm) on the dorsum, which was repaired with the EGF gene-modified human keratinocyte suspension and autologous microskin and covered with the allogeneic skin. The wound healing was quantified, and the expression of EGF mRNA was measured by RT-PCR. RESULTS: The EGF gene-modified human keratinocytes highly expressed EGF. CK10, CK14, and CK19 as keratinocyte differentiation markers were increased in the EGF gene-modified human keratinocytes. Wound healing was accelerated remarkably by the combination of autologous microskin grafting and EGF gene-modified human keratinocytes in vivo, and a very high EGF mRNA expression was observed in EGF gene-modified human keratinocytes groups on days 7 and 14 compared with other groups. DISCUSSION/CONCLUSION: The EGF gene-modified human keratinocyte suspension may serve as promising seed cells which can effectively secrete EGF to accelerate wound repair in combination with autologous microskin grafting and reduce the autologous skin requirement for wound repair.

Effect of First Trough Vancomycin Concentration on the Occurrence of AKI in Critically Ill Patients: A Retrospective Study of the MIMIC-IV Database.

Background: Vancomycin can effectively inhibit Gram-positive cocci and is widely used in critically ill patients. This study utilized a large public database to explore the effect of patients' first vancomycin trough concentration (FVTC) on the occurrence of acute kidney injury (AKI) and mortality after receiving vancomycin treatment in intensive care unit (ICU). Methods: Critically ill patients who used vancomycin in the Medical Information Mart for Intensive Care (MIMIC) IV have been retrospectively studied. The outcomes included the occurrence of AKI during the use of vancomycin or within 72 h of withdrawal, ICU mortality and hospital mortality. Restricted cubic splines (RCS) were used to analyze the linear relationship between FVTC and the outcomes. Multivariate logistic/Cox regression analysis was used to analyze the association between patient's FVTC and the occurrence of AKI, ICU mortality, and in-hospital mortality. Results: The study ultimately included 3,917 patients from the MIMIC-IV database who had been treated with vancomycin for more than 48 h. First of all, the RCS proved the linear relationship between FVTC and the outcomes. After controlling for all covariates as confounders in logistic/Cox regression, FVTC was a risk factor with the occurrence of AKI (OR: 1.02; 95% CI: 1.01-1.04), ICU mortality (HR: 1.02; 95% CI: 1.01-1.03), and in-hospital mortality (HR: 1.02; 95% CI: 1.01-1.03). Moreover, patients were divided into four groups in the light of the FVTC value: group1 ≤ 10 mg/L, 10 20 mg/L. Categorical variables indicated that group 3 and group 4 had a significant relationship on the occurrence of AKI [group 3: (OR: 1.36; 95% CI: 1.02-1.81); group 4: (OR: 1.76; 95% CI: 1.32-2.35)] and ICU mortality [group 3: (HR: 1.47; 95% CI: 1.03-2.09); group 4: (HR: 1.87; 95% CI: 1.33-2.62)], compared to group 1, while group 4 had a significant effect on in-hospital mortality (HR: 1.48; 95% CI: 1.15-1.91). Conclusions: FVTC is associated with the occurrence of AKI and increased ICU and in-hospital mortality in critically ill patients. Therefore, in clinical practice, patients in intensive care settings receiving vancomycin should be closely monitored for FVTC to prevent drug-related nephrotoxicity and reduce patient mortality.

Risk factor analysis and nomogram for predicting in-hospital mortality in ICU patients with sepsis and lung infection.

BACKGROUND: Lung infection is a common cause of sepsis, and patients with sepsis and lung infection are more ill and have a higher mortality rate than sepsis patients without lung infection. We constructed a nomogram prediction model to accurately evaluate the prognosis of and provide treatment advice for patients with sepsis and lung infection. METHODS: Data were retrospectively extracted from the Medical Information Mart for Intensive Care (MIMIC-III) open-source clinical database. The definition of Sepsis 3.0 [10] was used, which includes patients with life-threatening organ dysfunction caused by an uncontrolled host response to infection, and SOFA score ≥ 2. The nomogram prediction model was constructed from the training set using logistic regression analysis, and was then internally validated and underwent sensitivity analysis. RESULTS: The risk factors of age, lactate, temperature, oxygenation index, BUN, lactate, Glasgow Coma Score (GCS), liver disease, cancer, organ transplantation, Troponin T(TnT), neutrophil-to-lymphocyte ratio (NLR), and CRRT, MV, and vasopressor use were included in the nomogram. We compared our nomogram with the Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score II (SAPSII), the nomogram had better discrimination ability, with areas under the receiver operating characteristic curve (AUROC) of 0.743 (95% C.I.: 0.713-0.773) and 0.746 (95% C.I.: 0.699-0.790) in the training and validation sets, respectively. The calibration plot indicated that the nomogram was adequate for predicting the in-hospital mortality risk in both sets. The decision-curve analysis (DCA) of the nomogram revealed that it provided net benefits for clinical use over using the SOFA score and SAPSII in both sets. CONCLUSION: Our new nomogram is a convenient tool for accurate predictions of in-hospital mortality among ICU patients with sepsis and lung infection. Treatment strategies that improve the factors considered relevant in the model could increase in-hospital survival for these ICU patients.

Upregulation of TRPM8 can promote the colon cancer liver metastasis through mediating Akt/GSK-3 signal pathway.

This study aims to clarify the function of transient receptor potential melastatin 8 (TRPM8) in colon cancer liver metastasis. First, TRPM8 expression was determined by Western blotting in colon cancer patients with/without liver metastasis. Second, colon cancer cells were grouped into Mock, siCON, and siTRPM8 groups. Then, a series of in vitro experiments were conducted. Last, CT26 cells were used to construct colon cancer liver metastasis models on mice in vivo, followed by comparison of liver metastasis and determination of AKT/glycogen synthase kinase-3ß (GSK-3ß) pathway. Consequently, TRPM8 was upregulated in both colon cancer patients with/without liver metastasis, especially in those with metastasis. Compared with Mock and siCON groups, cells in siTRPM8 group demonstrated significant decreases in clone numbers, cell invasion, and migration; and obvious downregulations of p-AKT/AKT, p-GSK3ß/GSK3ß, Snail, and Vimentin, with an upregulation of E-cadherin. For in vivo experiments, a sharp decrease was observed in metastatic liver of mice in siTRPM8 group, with significant downregulations of p-AKT/AKT, p-GSK3ß/GSK3ß, Snail, and Vimentin and an upregulation of E-cadherin, as compared with Mock and siCON groups. Thus, TRPM8 was upregulated in colon cancer patients with liver metastasis, and silencing TRPM8 may suppress the progression and epithelial-mesenchymal transition of colon cancer cells to block its liver metastasis possibly by inhibiting AKT/GSK-3ß pathway.

Design, Synthesis, and Apoptosis-Promoting Effect Evaluation of Chalcone Derivatives Containing Aminoguanidine Units.

BACKGROUND: Chalcones are precursors of flavonoids or isoflavonoids, and they are abundant in edible plants. Chalcones constitute an important group of natural and synthetic products with a wide range of pharmacological activities. OBJECTIVE: To determine the seeds of the anti-tumor agents, we focused on the potential bioactive materials obtained from chalcone derivatives. METHODS: Two series of chalcone derivatives containing aminoguanidine or bis-chalone were designed, synthesized, and screened for their cytotoxicity, proliferation inhibition, and apoptosis-promoting activity in vitro against a panel of human tumor cell lines. RESULTS: Among the various compounds studied in this work, 2-((E)-4-((E)-3-oxo-3-(p-tolyl)prop-1-en-1- yl)benzylidene)hydrazine-1-carboximidamide (5f) was the most potent, with IC50 values of 7.17 µM and 3.05 µM antiproliferative activity in vitro against human hepatocarcinoma HepG2 cells and SMMC-7721 cells, respectively. This result showed that the compound possessed a certain degree of selectivity for human hepatocarcinoma cells, especially for SMMC-7721. Then, Annexin V/PI flow cytometry assay was used to investigate different concentrations of compound 5f to demonstrate the ability of compound 5f in inducing apoptosis of SMMC-7721 cells in a concentrationdependent manner. Finally, these results were further verified by Western blot analysis. CONCLUSION: Based on the collective results, compound 5f may be a promising anti-cancer compound, and may play a significant role in subsequent research.

[Preparation of branched polyethyleneimine-assisted boric acid-functionalized magnetic nanoparticles and its application to selective enrichment of ginsenoside Re].

Panax ginseng has a 5000-year-long history as a traditional herbal medicine in Eastern Asia and North America. It is also known as crown jewel in traditional Chinese herbs because of its wide pharmacological properties. Ginsenosides, a class of saponins containing triterpene aglycones and various sugar moieties, are the main active components of ginseng. Considering the low abundance of ginsenosides and other abundant interferences, separation of ginsenosides is essential prior to further analysis. Recently, our group demonstrated the potential of a boronate affinity material for the selective enrichment of ginsenosides. However, conventional boronate affinity materials suffer from an apparent drawback. The binding strength of boronic acids toward cis-diol-containing compounds is low, with dissociation constants (Kd) ranging from 10-1 to 10-3mol/L. Thus, it is necessary to develop boronate affinity materials with high binding strength. In this study, we developed polyethyleneimine (PEI)-functionalized boronate affinity magnetic nanoparticles (BA-MNPs) for the selective enrichment of ginsenosides. Branched PEI was applied as a scaffold to amplify the number of boronic acid moieties, while 3-formylphenylboronic acid, which shows high affinity toward cis-diol-containing molecules, was used as the affinity ligand. In addition, the presence of the multi-glycan structure of ginsenoside leads to higher binding affinity between the PEI-BA-MNPs due to the synergistic multivalent binding effect. Combining with high performance liquid chromatography, a method for the selective analysis of ginsenosides was established. With ginsenoside Re as the representative and under the optimized conditions for magnetic solid-phase extraction, the developed method showed good linearity in the range of 50-800 µg/L, with a linear correlation coefficient (R2) of 0.9681. At different spiked levels (0.1-10 mg/L), the recoveries were in the range of 91.5%-117.3%, and the relative standard deviations (RSDs) ranged from 7.2% to 13.4%. Since the PEI-BA-MNPs exhibited significantly improved binding strength toward ginsenosides, they could extract trace glycoproteins. After enrichment, a 50-fold improvement in the sensitivity was achieved. In addition, the PEI-BA-MNPs maintained at least 72% of their original binding capacity after five consecutive uses. Finally, the developed method was applied to the determination of ginsenoside Re in commercial medicine (Qipi oral liquid). As opposed to the tedious and time-consuming sample preparation in the standard method (Pharmacopoeia of the People's Republic of China, 2015; ChP2015), the present protocol allowed for direct enrichment of the diluted commercial medicine with PEI-BA-MNPs. The magnetic separation made the overall experiment much simpler than the standard ChP2015 method. After washing and elution, the enriched ginsenoside Re was eluted and subjected to HPLC-UV analysis. The results obtained with the developed method (0.27%) were similar to those of ChP2015 (0.31%). We have experimentally demonstrated that PEI-BA-MNPs are ideal affinity sorbents for the selective enrichment of ginsenosides owing to their significant advantages, including high affinity, excellent selectivity, easy manipulation, high binding capacity, and fast binding equilibrium. As many saponins contain sugar side chains, we foresee a promising prospect for the proposed method in real-world applications.

Effects of Exendin-4 on pancreatic islets function in treating hyperglycemia post severe scald injury in rats.

BACKGROUND: It has been established that glucagon-like peptide 1 (GLP 1) inhibits pancreatic ß-cell apoptosis, increases insulin secretion, and improves glucose tolerance in scald injury. However, the effects of Exendin-4, a long-acting incretin similar to GLP 1, remained unclear in severe scald injury. Hence, this study attempted to investigate whether Exendin-4 had similar effects by protecting the histology of pancreas in severely scalded rats. METHODS: One hundred sixty-two adult Wistar rats were equally randomized to sham burn group, burn group and burn with Exendin-4 treatment group. Rats were subjected to full skin thickness scald injuries (total body surface area: 50%) and were injected subcutaneously with Exendin-4 (4 µg/kg) twice daily. The histological changes of islets, the apoptosis of ß cells, the amount of glucagon and insulin, and the concentration of plasma glucagon and insulin were observed; and the intraperitoneal glucose tolerance test was performed as well. RESULTS: The islets and ß cells were injured and the number of secretory granules decreased in the scalded rats, but less histopathological changes were seen in the rats treated with Exendin-4. The apoptosis index of treated rats was significantly lower than that of the scalded rats (p < 0.05). There was significant difference in ß-cell density postinjury between the two groups (p < 0.05). More insulin and less glucagon in islets and plasma were found in the treated rats (p < 0.05), suggesting improved intraperitoneal glucose tolerance (p < 0.05) and fasting blood glucose (p < 0.05) in this group. CONCLUSION: Based on our previous finding that GLP-1 could control hyperglycemia by increasing insulin secretion and inhibiting ß-cell apoptosis in severe scald injuries, this study further confirmed that Exendin-4 could increase glycemic control following severe scald by preserving the histology of ß cells in pancreatic islets and inhibiting their apoptosis.

Bone mesenchymal stem cells transplantation combined with mild hypothermia improves the prognosis of cerebral ischemia in rats.

Bone marrow mesenchymal stem cells (BMSCs) are used as a great promising choice for the treatment of cerebral ischemia. Herein, we discuss the neuroprotective effects of the combination of BMSCs transplantation and mild hypothermia (MH) in an ischemia-reperfusion rat model. First, BMSCs were isolated using density gradient centrifugation and the adherent screening method, followed by culture, identification and labeling with DAPI. Second, adult male SD rats were divided into 5 groups: sham group (surgery without blockage of middle cerebral artery), model group (middle cerebral artery occlusion (MCAO) was established 2h prior to reperfusion), BMSCs group (injection of BMSCs via the lateral ventricle 24h after MCAO), MH group (mild hypothermia for 3h immediately after MCAO) and combination therapy group (combination of BMSCs and MH). Finally, the modified neurological severity score (mNSS) test was performed to assess behavioral function at different time points (before MCAO, before transplantation, at day 1, day 5 and day 10 after transplantation). After that, the brain was subjected to TTC staining, and the homing and angiogenesis were evaluated by immumofluorescence and immunohistochemistry. Immunofluorescence staining and Western Blot analysis were performed to calculate the percentage of the infarct area and explore glial fibrillary acidic protein (GFAP) and vascular endothelial growth factor (VEGF). Our results showed that the combination therapy significantly decreased mNSS scores (P<0.01) and reduced the percentage of the infarct area (P<0.01) than a single treatment. Moreover, the expression of GFAP and VEGF increased significantly in the combination therapy group (at day 5, day 10 after transplantation; at all time points after transplantation, respectively) compared to the single treatment groups. Taken together, it was suggested that the combination of BMSCs transplantation and MH can significantly reduce the percentage of the infarct area and improve functional recovery by promoting homing and angiogenesis, which may be a beneficial treatment for cerebral ischemia.

[AN EXPERIMENTAL STUDY ON REPAIR OF FULL THICKNESS SKIN WOUND WITH GRAFT OF AUTOLOGOUS KERATINOCYTE SUSPENSION IN RATS].

OBJECTIVE: To investigate the application of autologous keratinocyte suspension transplantation in skin reconstruction. METHODS: Forty adult Sprague Dawley rats (weighing, 210-230 g) were randomly divided into 4 groups (n=10): high density keratinocyte suspension transplantation (1X106 cells/cm2) group (group A), middle density (1 x 10(5) cells/cm2) group (group B), low density (1 x 10(4) cells/cm2) group (group C), and control group (group D). Skin samples were harvested from the rats in groups A, B, C for the isolation of keratinocytes. The model of anti-contracture of full thickness skin wound was made in rats and autologous keratinocyte suspension was transplanted into the wound. The wound was covered by the allogeneic skin (allogeneic skin derived from Wistar rats). The survival of rats was observed after operation. The survival of allogeneic skin was observed at 7, 14, and 21 days after operation, and wound healing rate was calculated after allogeneic skin dropped off. Histological staining and immunohistochemical staining were carried out at 21 days after operation. RESULTS: All the rats survived to the end of the experiment. The allograft skins survived in all groups, dried and dropped off. The epithelium sheet could be seen in groups A and B at 21 days, a few very thin epithelium in group C, and no epithelization in group D. The wound healing rate of groups A (62.9% +/- 9.6%) and B (64.2% +/- 9.1%) were significantly higher than that of groups C (38.5% +/- 5.7%) and D (22.7% +/- 5.5%) (P<0.05), and significant difference was found between groups C and D (P<0.05), but there was no significant difference between groups A and B (P>0.05). The results of histological observation showed that squamous epithelial cells were observed in groups A, B, and C, but not in group D; obvious layers of epidermis were observed in groups A and B, thin epidermis and inflammatory cell infiltration in group C, and granulation tissue in group D. The immunohistochemistry staining showed that the expressions of collagen type IV and collagen type VII in groups A, B, and C; the percentage of collagen type IV and collagen type VII positive cells in groups A and B were significantly higher than that of group C (P<0.05), but there was no significant difference between groups A and B (P>0.05). The expressions of collagen type IV and collagen type VII in group D were negative. CONCLUSION: The repair of full thickness skin wound with graft of autologous keratinocyte suspension can achieve reconstruction of the skin. The appropriate density of keratinocyte suspension for wound healing is 1 x 10(5) cells/cm2.

[Effects of transfection of human epidermal growth factor gene with adenovirus vector on biological characteristics of human epidermal cells].

OBJECTIVE: To investigate the suitable transfection condition of human epidermal cells (hECs) with human epidermal growth factor (EGF) gene by adenovirus vector (Ad-hEGF) and its effects on the biological characteristics of hECs. METHODS: hECs were isolated from deprecated human fresh prepuce tissue of circumcision by enzyme digestion method and then sub-cultured. hECs of the third passage were used in the following experiments. (1) Cells were divided into non-transfection group and 5, 20, 50, 100, 150, and 200 fold transfection groups according to the random number table (the same grouping method below), with 3 wells in each group. Cells in non-transfection group were not transfected with Ad-hEGF gene, while cells in the latter six groups were transfected with Ad-hEGF gene in multiplicities of infection (MOI) of 5, 20, 50, 100, 150, and 200 respectively. The morphology of the cells was observed with inverted phase contrast microscope, and expression of green fluorescent protein of the cells was observed with inverted fluorescence microscope at transfection hour (TH) 24, 48, and 72. (2) Another three batches of cells were collected, grouped, and treated as above, respectively. Then the transfection rate of Ad-hEGF gene was detected by flow cytometer (n=3), the mass concentration of EGF in culture supernatant of cells was detected by enzyme-linked immunosorbent assay (n=6), and the proliferation activity of cells was detected by cell counting kit 8 (CCK8) and microplate reader (n=6) at TH 24, 48, and 72, respectively. (3) Cells were collected and divided into non-transfection group and transfection group, with 6 wells in each group. Cells in non-transfection group were cultured with culture supernatant of cells without transfection, while cells in transfection group were cultured with culture supernatant of cells which were transfected with Ad-hEGF gene in the optimum MOI (50). CCK8 and microplate reader were used to measure the biological activity of EGF secreted by cells on culture day 1, 3, and 5. (4) Cells were collected and divided into non-transfection group and transfection group, with 12 wells in each group. Cells in non-transfection group were not transfected with Ad-hEGF gene, while cells in transfection group were transfected with Ad-hEGF gene in the optimum MOI (50). The expression levels of cytokeratin 14 (CK14) and CK19 of cells were measured by immunofluorescence staining at TH 24. (5) Cells were collected, grouped, and treated as in (4), with 6 wells in each group. At post scratch hour (PSH) 0 (immediately after scratch), 12, 24, and 48, the migration distance of cells was observed and measured with inverted phase contrast microscope. Data were processed with analysis of variance of factorial design, analysis of variance for repeated measurement, and LSD test. RESULTS: (1) At TH 24 and 48, morphology of cells in each transfection group and non-transfection group were similar. Compared with that in non-transfection group, the cell debris increased significantly in 200 fold transfection group at TH 72. At TH 24, 48, and 72, the expression of green fluorescent protein was not seen in cells of non-transfection group, whereas it increased in cells of transfection group over transfection time. (2) The transfection rate of Ad-hEGF gene of cells in each transfection group increased gradually over transfection time. At TH 72, the transfection rates of Ad-hEGF gene of cells in 50-200 fold transfection groups were all above 90%, while the transfection rates of Ad-hEGF gene of cells in non-transfection group, 5, and 20 fold transfection groups were (0.51±0.20)%, (62.44±6.23)%, and (75.00±5.43)% respectively, which were obviously lower than the rate in 50 fold transfection group [(93.12±2.55)%, with P values below 0.01]. The mass concentration of EGF in culture supernatant of cells in each transfection group increased gradually over transfection time. At TH 72, the mass concentration of EGF in culture supernatant of cells in 50 fold transfection group was obviously higher than that in each of the other groups (with P values below 0.01). The proliferation activity of cells in each group at TH 24 and 48 was similar (with P values above 0.05). At TH 72, the proliferation activity of cells in 200 fold transfection group was obviously lower than that in other groups (with P values below 0.05). (3) On culture day 1, the biological activity of EGF secreted by cells in two groups was similar (P>0.05). On culture day 3 and 5, the biological activity of EGF secreted by cells in transfection group were obviously higher than that in non-transfection group (with P values below 0.01). (4) At TH 24, the expression levels of CK14 and CK19 of cells in transfection group were higher than those in non-transfection group. (5) The width of scratch in two groups was nearly the same at PSH 0. At PSH 12-48, the migration distance of cells in transfection group was obviously longer than that in non-transfection group (with P values below 0.01). CONCLUSIONS: The suitable range of MOI of hECs transfected with Ad-hEGF gene is 50-150, and 50 is the optimum. hECs transfected with Ad-hEGF gene with MOI 50 can effectively express the EGF gene and keep its good abilities of proliferation, differentiation, and migration, as well.

[Application of vacuum sealing drainage in the treatment of severe necrotizing fasciitis in extremities of patients].

OBJECTIVE: To study the application of VSD in the treatment of severe necrotizing fasciitis in extremities of patients. METHODS: Eight patients, suffering from severe necrotizing fasciitis, who had been traditionally treated with iodophor-soaked gauze for 21 to 365 days in other hospitals, were transferred to our institute because of the nonhealing wounds and systemic toxic symptoms induced by infection, from January 2011 to August 2013. After admission, surgical debridement was performed timely, and the necrotic tissue was collected during the operation for pathological observation after HE staining. After the operation, VSD was started with negative pressure ranging from -100 to -80 kPa, and the furacilin solution (0.2 g/L) and oxygen (2 L/min) were continuously infused into the wound during the treatment. Surgical debridement was performed repeatedly according to the wound condition followed by change of VSD dressings to continue VSD treatment. The wounds were closed by suturing or with autologous skin grafts after being covered by fresh granulation tissue. The times of surgical debridement, times of change of VSD materials, wound healing status, and length of stay in our institute were recorded. All patients were followed up for a long time. Results HE staining showed that there were diffuse necrotic adipose and fibrous connective tissues in the necrotic tissue, and the normal tissue structure disappeared accompanied by significant infiltration of inflammatory cells. The number of surgical debridement was 2 to 10 (3.9 +/- 2.8) times. The number of VSD materials change was 2 to 10 (4.0 +/- 2.9) times. Wounds were closed by suturing and healed in two patients; wounds in the other six patients were partially sutured, their residual wounds were healed by autologous skin grafting. The length of stay in our institute was 20 to 49 (33 +/- 10) days. All patients were discharged after recovery. Patients were followed up for 2 to 24 months, and their wounds were found to be in good condition without ulceration or recurrence. CONCLUSIONS: VSD can effectively remove the necrotic tissues and exudates from the fascial spaces and promote proliferation of granulation tissue. Therefore it serves as an effective approach to the treatment of severe necrotizing fasciitis in extremities.

Can routine oral care with antiseptics prevent ventilator-associated pneumonia in patients receiving mechanical ventilation? An update meta-analysis from 17 randomized controlled trials.

BACKGROUND: Whether oral antiseptics could reduce the risk of ventilator associated pneumonia (VAP) in patients receiving mechanical ventilation remains controversial. We performed a meta-analysis to assess the effect of oral care with antiseptics on the prevalence of ventilator associated pneumonia in adult critically ill patients. METHODS: A comprehensive search of PubMed, Embase and Web of Science were performed to identity relevant studies. Eligible studies were randomized controlled trials of mechanically ventilated adult patients receiving oral care with antiseptics. The quality of included studies was assessed by the Jadad score. Relative risks (RRs), weighted mean differences (WMDs), and 95% confidence intervals (CIs) were calculated and pooled using a fixed-effects model or random-effects model. Heterogeneity among the studies was assessed with I (2) test. RESULTS: 17 studies with a total number of 4249 met the inclusion criteria. Of the 17 studies, 14 assessed the effect of chlorhexidine, and 3 investigated the effect of povidone-iodine. Overall, oral care with antiseptics significantly reduced the prevalence of VAP (RR=0.72, 95% CI: 0.57, 0.92; P=0.008). The use of chlorhexidine was shown to be effective (RR=0.73, 95% CI: 0.57, 0.93; P=0.012), whereas this effect was not observed in povidone-iodine (RR=0.51, 95% CI: 0.09, 2.82; P=0.438). Subgroup analyses showed that oral antiseptics were most marked in cardiac surgery patients (RR=0.54, 95% CI: 0.39, 0.74; P=0.00). Patients with oral antiseptics did not have a reduction in intensive care unit (ICU) mortality (RR=1.11, 95% CI: 0.95, 1.29; P=0.201), length of ICU stay (WMD=-0.10 days, 95% CI: -0.25, 0.05; P=0.188), or duration of mechanical ventilation (WMD=-0.05 days, 95% CI: -0.14, 0.04; P=0.260). CONCLUSION: Oral care with antiseptics significantly reduced the prevalence of VAP. Chlorhexidine application prevented the occurrence of VAP in mechanically ventilated patients but povidone-iodine did not. Further large-scale, well-designed randomized controlled trials are needed to identify the findings and determine the effect of povidone-iodine application.

[Structural and functional changes in islet beta cells in severely scalded rats].

OBJECTIVE: To observe the structural and functional changes in islet beta cells in severely scalded rats, and to explore its relationship with dysfunction of glycometabolism. METHODS: Seventy-two Wistar rats were divided into scald (S) group and sham injury (SI) group according to the random number table, with 36 rats in each group. Rats in group S were inflicted with 50%TBSA full-thickness scald by a 12-s immersion of back and a 6-s immersion of abdomen in 94 °C hot water. Rats in group SI were sham injured through immersion of back and abdomen in 37 °C warm water. At post injury hour (PIH) 6 and on post injury day (PID) 3 and 7, plasma glucose level was measured for intraperitoneal glucose tolerance test (IPGTT) in 12 rats of each group, and the area under the curve (AUC) of plasma glucose level was calculated. After the IPGTT, pancreatic tissue was harvested and subjected to a double immunostaining for insulin and cell nuclei to determine the pancreatic insulin-positive area ratio, and the area and number of beta cells in the islets (referred to as "the three indicators in the islets"). Data were processed with the analysis of repeated measures and factorial designed analysis of variance, and LSD test was applied for paired comparison. RESULTS: (1) At PIH 6 and on PID 3, the overall plasma glucose levels of rats in group S before and after injection of glucose and at each time point were obviously higher than those of rats in group SI (with F values of main effects respectively 79.372 and 32.962, P values all below 0.001; with P values of paired comparison below 0.05 or 0.01). On PID 7, the overall plasma glucose levels in the two groups before and after injection of glucose and at each time point were close (with P values all above 0.05). (2) The overall AUC of plasma glucose levels of rats in group S was higher than that of rats in group SI (main effects: F = 337.87, P < 0.01). Compared with those of rats in group SI [(1019 ± 32), (1003 ± 72) mmol·min·L(-1)], the AUCs of plasma glucose levels of rats in group S were higher at PIH 6 and on PID 3 [(1501 ± 163), (1132 ± 67) mmol·min·L(-1), P values all below 0.001]. The AUCs of plasma glucose levels were close between two groups on PID 7 (P > 0.05). The AUCs of plasma glucose levels on PID 3 and 7 were both lower than that at PIH 6 in rats of group S (with P values all below 0.001). (3) The three indicators in the islets in rats of group S were all lower than those of rats in group SI (with F values of main effects respectively 135.17, 24.75 and 39.35, P values all below 0.01). There were no significant differences in the three indicators in the islets at PIH 6 between two groups (with P values all above 0.05). The three indicators in the islets of rats in group S on PID 3 and 7 [0.47 ± 0.05, 0.51 ± 0.07; (0.032 ± 0.008), (0.037 ± 0.008) mm(2); (303 ± 64), (341 ± 58) cells] were significantly lower than those of rats in group SI [0.63 ± 0.05, 0.64 ± 0.06; (0.043 ± 0.011), (0.044 ± 0.012) mm(2); (398 ± 112), (387 ± 90) cells; P < 0.05 or P < 0.01] and that at PIH 6 within group S (P < 0.05 or P < 0.01). CONCLUSIONS: The number of beta cells is reduced, and the insulin secretion function of beta cells is decreased in the scalded rats, and they may constitute the cause of dysfunction of glycometabolism, mainly manifested as hyperglycemia.

Growth inhibitory effect of 4-phenyl butyric acid on human gastric cancer cells is associated with cell cycle arrest.

AIM: To investigate the growth effects of 4-phenyl butyric acid (PBA) on human gastric carcinoma cells and their mechanisms. METHODS: Moderately-differentiated human gastric carcinoma SGC-7901 and lowly-differentiated MGC-803 cells were treated with 5, 10, 20, 40, and 60 µmol/L PBA for 1-4 d. Cell proliferation was detected using the MTT colorimetric assay. Cell cycle distributions were examined using flow cytometry. RESULTS: The proliferation of gastric carcinoma cells was inhibited by PBA in a dose- and time-dependent fashion. Flow cytometry showed that SGC-7901 cells treated with low concentrations of PBA were arrested at the G0/G1 phase, whereas cells treated with high concentrations of PBA were arrested at the G2/M phase. Although MGC-803 cells treated with low concentrations of PBA were also arrested at the G0/ G1 phase, cells treated with high concentrations of PBA were arrested at the S phase. CONCLUSION: The growth inhibitory effect of PBA on gastric cancer cells is associated with alteration of the cell cycle. For moderately-differentiated gastric cancer cells, the cell cycle was arrested at the G0 /G1 and G2/M phases. For lowly-differentiated gastric cancer cells, the cell cycle was arrested at the G0/G1 and S phases.

[Study on the correlation between membrane protein Flotillin-1 and PrPc endocytosis].

OBJECTIVE: To explore whether the membrane-associated protein Flotillin-1 has relationship with endocytosis of PrPc. METHODS: The expression of Flotillin-1 in different cell lines was detected with the method of Western Blot; the interaction between Flotillin-1 and PrPc in Cells which were treated with copper ions was observed using immunoprecipitation method. RESULTS: (1) Flotillin-1 was widely expressed in many cell lines without significant difference in the amounts of expression level; (2) Only in the appearance of copper ions, the protein complexes of PrPc and Flotillin-1 can be detected with the method of IP, which were related to copper ions concentration and processing time. CONCLUSION: The membrane-associated protein Flotillin-1 has the relationship with the endocytosis of PrPc.

[Mutant D178N prion protein converts spontaneously in RT-QuIC assay].

OBJECTIVE: To study the conversion of mutant D178N prion protein in RT-QuIC assay. METHODS: The D178N mutant prion PRNP was generated by the method of single site mutation. The mutant PRNP gene was inserted into plasmids of pET24. The full and N-truncated recombinant human prion proteins were expressed and purified. The fibril formations of these proteins were real-time monitored by the method of RT-QuIC. The ability to resist proteinase K (PK) of these fibrils was analyzed. RESULTS: We succeed to construct human PrP-D178N plamids. The N-truncated human prion protein with D178N (PrP90-231-D178N) can convert spontaneously in RT-QuIC, while full length of human prion D178N protein (PrP23-231-D178N) fails to convert spontaneously. The spontaneously generated fibril has been domenstrated it is partily PK-resistant. CONCLUSION: The N-terminal of prion protein (23-90) plays an important role for the D178N mutant protein spontaneously conversion, which provide the clues for study the pathogenesis of genetic CJD.