A modified culture strategy of human keratinocytes to shorten the primary culture time.

Shortening time from biopsy to graft preparation is crucial for the coverage of extensive burn wound in major burn patients. This study was aimed to shorten the culture time of keratinocytes by means of one modified cell culture method. Three factors (temperature of dispase, area of skin, and age of patient) that might have impacts on cell behavior were evaluated. The results showed that cells isolated with dispase at 37°C exhibited an improved cell activity than being isolated at 4°C. The time that cells reached subconfluence with various skin areas was in order of 3 cm(2) < 2 cm(2) < 1 cm(2) (120.07 ± 5.03 h, 141.33 ± 4.16 h, and 193.33 ± 6.11 h, respectively). Furthermore, compared with the young and middle-aged groups, proliferation of keratinocytes isolated from children skin tissue was better. These results indicated that 3 cm(2) skin biopsy from a young patient, isolated with dispase at 37°C, was a promising strategy to shorten the cultivation of keratinocytes.

Cytidine diphosphate choline improves the outcome of cardiac arrest vs epinephrine in rat model.

OBJECTIVES: Cytidine diphosphate choline (CDP-choline) is a cholinergic agent that can both stimulate the cholinergic pathway and increase blood pressure. We aimed to investigate the effects of CDP-choline on the outcome of cardiac arrest in comparison with epinephrine. METHODS: This was a randomized prospective animal study. Cardiac arrest was induced by asphyxia in 45 rats. After 7 minutes of asphyxia, resuscitation was attempted. The rats were allocated to different groups treated with 2 mL/kg saline, 100 µg/kg epinephrine, or 250 mg/kg CDP-choline. The hemodynamic parameters were monitored for 2 hours after resuscitation, and cardiac function was evaluated by echocardiography 2 hours after resuscitation. The hearts were harvested at the end of monitoring for histologic evaluation. RESULTS: Epinephrine and CDP-choline improved the rate of return of spontaneous circulation and blood pressure during cardiopulmonary resuscitation; however, postresuscitation cardiac function in the CDP-choline and placebo groups was better than in the epinephrine group. Compared with the epinephrine group, less myocardial and mitochondrial injury was observed by electron microscopy in the CDP-choline and placebo groups; the level of superoxide dismutase and malondialdehyde indicated less peroxidative injury in the CDP-choline and placebo groups. Cytidine diphosphate choline and placebo also preserved connexin 43 when compared with epinephrine. CONCLUSION: When administered during resuscitation, CDP-choline increased the rate of return of spontaneous circulation similarly to epinephrine. In addition, it did not increase the severity of myocardial injury and postresuscitation myocardial dysfunction, whereas epinephrine appeared to be harmful.

Comparison of fecal microbiota of SPF and non-SPF Beagle dogs.

Microbial colonization of animal intestine impacts host metabolism and immunity. The study was aimed to investigate the diversity of the intestinal microflora in specific pathogen free (SPF) and non-SPF Beagle dogs of different ages by direct sequencing analysis of the 16S rRNA gene. Stool samples were collected from four non-SPF and four SPF healthy Beagle dogs. From a total of 792 analyzed Operation taxonomic units, four predominant bacterial phyla were identified: Firmicutes (75.23%), Actinobacteria (10.98%), Bacteroidetes (9.33%), and Proteobacteria (4.13%). At the genus level, Streptococcus, Lactobacillus, and Bifidobacterium were dominated. Among which, Alloprevotella, Prevotella_9, and Faecalibacterium were presented exclusively in non-SPF beagles, with potentially anti-inflammatory capability, which could protect non-SPF beagles from complex microbial environment. The number and diversity of intestinal flora for non-SPF Beagle dogs were the highest at birth and gradually decreased with growth, whereas the results for the SPF beagle samples were the opposite, with the number and diversity of intestinal microbiota gradually increases as beagles grow. In a nutshell, the microbial complexity of the rearing environment can enrich the gut microbiota of beagles, many of which are anti-inflammatory microbiota with the potential to increase the adaptability of the animal to the environment. However, the gut microbiota of SPF beagles was more sensitive to environmental changes than that of non-SPF beagles. This study is of great significance for understanding the bionomics of intestinal microflora in non-SPF and SPF beagles, improving the experimental accuracy in scientific research.

Electrostatic assemblies of molecularly imprinted polymers on the surface of electrospun nanofiber membranes for the point-of-care detection of thiodiglycol, a sulfur mustard poisoning metabolic marker.

In this study, molecularly imprinted polymers (MIPs) were assembled on the surface of ethylene imine polymer (PEI)/poly(vinyl alcohol) (PVA) electrospun nanofiber membranes for the point-of-care testing (POCT) of thiodiglycol (TDG), a sulfur mustard poisoning metabolic marker, using concentrated gold nanoparticles (AuNPs) as the signal reporting units. The MIPs/PEI/PVA nanofiber membranes could capture TDG specifically through the recognition interaction between MIPs and TDG. Then, AuNPs were adsorbed onto the MIPs/PEI/PVA nanofiber membranes through the Au-S interaction between TDG and AuNPs to produce a visible red color. In order to improve the sensitivity, the silver-enhanced solutions were used to deepen the color of the nanofiber membranes and the software Image J was used to read the gray value as the signal response for subsequent analysis. There was a good linear relationship between the color change of the MIPs/PEI/PVA nanofiber membranes and the TDG concentration from 0.1 ng mL-1 to 1.0 µg mL-1, and the limit of detection was 38 pg mL-1. This method was applied for the selective detection of TDG in urine, showing great potential for the clinical diagnosis of mustard gas poisoning.

TXNIP knockout improves cardiac function after myocardial infarction by promoting angiogenesis and reducing cardiomyocyte apoptosis.

Background: Myocardial infarction (MI) is a common cause of death. Thioredoxin-interacting protein (TXNIP) expression increases after MI, and it exerts a negative regulatory effect on cardiac function after MI. Our study aimed to investigate the specific regulatory mechanism of TXNIP on angiogenesis and cardiomyocyte apoptosis after MI. Methods: The TXNIP gene knock-in (TXNIP-KI) and knock-out (TXNIP-KO) mice were generated, respectively. Eight-week-old male TXNIP-KO, TXNIP-KI, and wild type (WT) mice were subjected to MI by permanent ligation of the left anterior descending artery. Cardiomyocyte apoptosis was detected by TUNEL assay on the 4th post-surgery day. The expressions of TXNIP, hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF), phosphorylated protein kinase B (p-AKT), p-AMP-activated protein kinase (p-AMPK), cleaved caspase-3, and caspase-3 were detected by Western blot. Quantitative real-time PCR was performed to detect the expression of TXNIP, HIF-1α, VEGF, prolyl hydroxylase (PHD) 1, and factor inhibiting HIF (FIH). In addition, the superoxide dismutase (SOD) activity and malondialdehyde (MDA) level in each group were also measured. On day 7 after MI, the hearts of sacrificed animals were analyzed by immunohistochemistry to assess CD31 expression and determine the density of angiogenesis. One month after treatment, the cardiac functional and structural changes were determined by echocardiography and the level of myocardial fibrosis was observed by Masson staining. Results: Compared with WT mice, TXNIP-KO mice had a significantly improved cardiac functional recovery after MI, and the proportion of myocardial fibrosis area was dramatically reduced, cardiomyocyte apoptosis was decreased, and angiogenesis was significantly increased; TXNIP-KI mice reversed in these changes. The expression of HIF-1α, p-AKT, and p-AMPK increased after MI in TXNIP-KO mice, and the mRNA expression of PHD 1 and FIH decreased. TXNIP-KI mice reversed in these changes. Conclusions: After MI, TXNIP down-regulated the level of HIF-1α and VEGF, reduced the number of angiogenesis, increased cardiomyocyte apoptosis, and ultimately led to a poor prognosis of ischemic myocardium. TXNIP was a protein with negative effects after MI and was expected to be a target for the prevention and treatment of MI.

Graphene oxide nanosheet-mediated fluorescent RPA "turn-on" biosensor for rapid RNAi transgenic plant detection.

In this paper preliminarily verified that graphene oxide (GO) nanomaterials enhanced the recombinase polymerase amplification (RPA). GO nanosheets improved the efficiency of RPA amplification by absorbing ingredients to induce local aggregation. The recombinase initially aggregated with the primers to form nucleoprotein filaments, absorbed on the GO nanosheets, changing the structure. Therefore, an isothermal fluorescence biosensor was developed based on GO nanosheets enhanced the RPA to detect RNA interference (RNAi) transgenic plants. FAM-labeled primers were absorbed and quenched by the GO nanosheets. After amplification, the primers were extended into double-stranded DNA, detaching from the GO surface to recover the fluorescent signal. The biosensor displayed high sensitivity and selectivity and showed an excellent relationship ranging from 1.5 to 100 ng of genome DNA, with a detection limit (LOD) of 1.5 ng. Consequently, the biosensor provides an enhanced isothermal method for detecting genetically modified (GM) products and exhibits significant potential for molecular detection.

Isolation and Antibiotic Resistant Research of Tetragenococcus halophilus from Xuanwei Ham, A China High-Salt-Fermented Meat Products.

We assessed the prevalence of antibiotic resistant and antibiotic resistance genes for 49 Tetragenococcus halophilus (T. halophilus) strains isolated from Xuawei ham in China. The antibiotic resistance phenotype was detected by the Bauer-Kirby (K-B) method and the results showed that 49 isolates can be considered completely susceptible to penicillin, ampicillin, amoxicillin, cefradine, cefotaxime, tetracyclines, minocycline, doxycycline, and vancomycin, but resistant to gentamicin, streptomycin, neomycin, polymyxinB, cotrimoxazole. This resistance was sufficiently high to consider the potential for acquisition of transmissible determinants. A total of 32 isolates were resistant to ofloxacin, 4 isolates were resistant to ciprofloxacin and chloramphenicol, and 2 isolates were resistant to ceftazidime and ticarcillin. The antibiotic resistance genes were detected by routine polymerase chain reaction (PCR). Among the 26 antibiotic resistance genes, 5 varieties of antibiotic resistance genes, including acrB, blaTEM, AAda1, SulII, and GyrB were detected and the detection rates were 89.79%, 47.7%, 16.33%, 77.55%, and 75.51%, respectively. The potential acquisition of transmissible determinants for antibiotic resistance and antibiotic resistance genes identified in this study necessitate the need for a thorough antibiotic resistance safety assessment of T. halophilus before it can be considered for use in food fermentation processes.

Study on Blending of Wall Material of the Nonel Tube by CSW/PE-g-MAH.

In order to improve the strength and resistance of ordinary nonel tubes, calcium sulfate whiskers (CSW, treated with silane coupling agent) and maleic anhydride grafted polyethylene (PE-g-MAH) are used to control the wall material of the nonel tube that the blending of the low-density polyethylene was enhanced. The effects of mass fraction of CSW or PE-g-MAH on the tensile properties, interfacial structure, melting and crystallization characteristics, and thermal decomposition behavior of the composite system were studied, and the thermal decomposition kinetics were calculated. The results show that, relative to pure LDPE, the strength of LDPE/CSW (85/15) is increased by 7.58%, and the strength of LDPE/CSW/PE-g-MAH (84/15/1) is increased by 7.58%. The addition of CSW or PE-g-MAH has gradually changed the fracture mode of the LDPE matrix. Thermal analysis shows that CSW can reduce the crystallinity of LDPE. The melting and crystallization characteristics of LDPE/CSW/PE-g-MAH composites have little effect, but the thermal decomposition stability is improved. The kinetic analysis showed that the reaction order (n) was around 1, CSW could improve LDPE/CSW thermal decomposition activation energy, and PE-g-MAH increased the thermal decomposition activation energy of LDPE/CSW/PE-g-MAH.

The roles of autophagy and apoptosis in burn wound progression in rats.

Understanding the role of cell death in burn wound progression is crucial for giving appropriate diagnoses and designing therapy regimens for burn patients. A well-described and reliable "comb burns model" was employed to evaluate the roles of autophagy and apoptosis in burn wound progression at 2 h, 6 h, 12 h, 24 h, and 48 h post-burn in a rat model. Immunohistochemistry (IHC) results showed that autophagy was detectable in hair follicle epithelium at 2 h post-burn, peaked at 12 h post-burn, then declined. Conversely, apoptosis was mainly located in the stratum epidermis and took place at low levels until 6 h post-burn, at which point it slowly increased. Bcl-2 and Bax, which are regulators of both processes, showed protein expression level patterns that were consistent with the IHC results. This study of autophagy in burn wound tissue progression represents a conceptual expansion of cell death in burn wounds. Based on these results, we suggest that different treatments should be performed on a specific post-burn time course depending on the most prevalent type of cell death occurring at that time.

The efficacy of straddling external chest compression on a moving stretcher.

OBJECTIVE: To evaluate the efficacy of straddling external chest compression performed on moving stretchers. METHODS: The study was a prospective, randomized, cross-over study on a manikin performed at a university hospital. Twenty subjects were selected from the 40 graduates using random numbers to participate in the study. Participants were randomized to either performing standard or straddling external chest compression followed by the other technique 7 days later. The compression variables and time to first compression were recorded. RESULTS: Twenty subjects (12 males and 8 females) took part in the study. There were no differences between the standard and straddling external chest compression for the compression rate, effective compression percentage and compression depth. There was no difference between the standard external chest compression and straddling external chest compression for incorrect hand position and incomplete release compression. Time to first compression during straddling external chest compression (10.31 ± 1.65 s) was greater than that during standard external chest compression (2.74 ± 0.40 s) (P < 0.001). CONCLUSIONS: The quality of straddling external chest compression performed on a moving stretcher was as effective as standard external chest compression performed on the floor. By performing straddling external chest compression, time for transporting victims to the emergency department to get advanced life support may be shortened.

The effect of two different counting methods on the quality of CPR on a manikin--a randomized controlled trial.

OBJECTIVES: To compare the quality of cardiopulmonary resuscitation (CPR) and rescuers' exhaustion using different methods of counting, and to establish an appropriate method of counting. MATERIALS AND METHODS: Forty-eight subjects who had received formal training in basic life support (BLS) were recruited from doctors and nurses working in the Emergency Department of a university hospital. They performed 3 min of continuous chest compressions using two different methods of counting, one after the other, on an adult resuscitation manikin. The total number of compressions, the number of these considered satisfactory, the peak heart rate of subjects and the time to peak heart rate were all recorded. Perceived fatigue and discomfort was evaluated by self-reported survey results with use of a visual analogue scale (VAS). RESULTS: The effective power of external chest compression and the mean compression depth when counting from 1 to 10, repeated three times, were greater than those achieved when counting from 1 to 30 during 3 min of CPR (67.48% vs. 57.81% and 44.52 mm vs. 40.48 mm, P<0.05). The exhaustion-score using the VAS (22.15 points) was lower and the time to peak heart rate (124.88 s) was longer when counting from 1 to 10, repeated three times, than when rescuers counted from 1 to 30. CONCLUSIONS: Counting from 1 to 10 three times in Chinese as opposed to 1-30 results in better quality chest compressions. Counting from 1 to 10 three times was associated with less user feelings of fatigue, and a longer time to peak heart rate. These findings support the teaching of counting compressions 1-10 three times during CPR.