Plasma proenkephalin and neutrophil gelatinase-associated lipocalin predict mortality in ICU patients with acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) is a common complication in patients admitted to intensive care unit (ICU) and mortality rates for this condition are high. To reduce the high incidence of short-term mortality, reliable prognostic indicators are required to facilitate early diagnosis and treatment of AKI. We assessed the ability of plasma proenkephalin (p­PENK) and plasma neutrophil gelatinase-associated lipocalin (p­NGAL) to predict 28-day mortality in AKI patients in intensive care. METHODS: This prospective study, carried out between January 2019 and December 2019, comprised 150 patients (100 male) diagnosed with AKI after excluding 20 patients discharged within 24 h and those with missing hospitalization data. Blood samples were collected to determine admission p-PENK and p-NGAL levels. The study outcome was 28­day mortality. RESULTS: The mean patient age was 68 years (female, 33%). The average P­PENK and p­NGAL levels were 0.24 ng/µL and 223.70 ng/mL, respectively. P­PENK levels >0.36 ng/µL and p­NGAL levels >230.30 ng/mL were used as critical values to reliably indicate 28­day mortality for patients with AKI (adjusted hazard ratios 0.785 [95% confidence interval 0.706-0.865, P<0.001] and 0.700 [95% confidence interval 0.611-0.789, P<0.001], respectively). This association was significant for mortality in patients in intensive care with AKI. Baseline p-PENK (0.36 ng/µL) and p-NGAL (230.30 ng/mL) levels and their respective cut-off values showed clinical value in predicting 28-day mortality. CONCLUSION: Serum PENK and NGAL levels, when used in conjunction, improved the accuracy of predicting 28-day mortality in patients with AKI while retaining sensitivity and specificity.

A microchip electrophoretic assay for DNA methyltransferase activity based on methylation-sensitive endonuclease Dpnâ ¡.

DNA methylation is a significant epigenetic modification and the methods for the detection of DNA methyltransferase (MTase) activity are important due to aberrant methylation closely related to the occurrence of cancer. In this study, a simple and rapid microchip electrophoresis (ME) coupled with LED-induced fluorescence (LEDIF) method was presented for the detection of Dam MTase activity. This strategy was based on methylation-sensitive endonuclease DpnⅡ which could recognize the same specific site 5'-GATC-3' with Dam MTase in double-stranded DNA (dsDNA). The adenines in the specific site could be methylated by Dam MTase, then the special site could not be digested by DpnⅡ. Both methylated dsDNA and unmethylated dsDNA could be analyzed by ME-LEDIF after stained by SYBR gold. The results showed the fluorescence intensities of methylated dsDNA were directly proportional to Dam MTase activities in the range of 0.5-20 U/mL with a detection limit of 0.12 U/mL. Furthermore, the method could successfully be applied to evaluation experiments of Dam MTase inhibitors. The results confirmed the ME-LEDIF method is a promising approach for inhibitors screening of DNA MTase and development of anticancer drugs.

Selective detection of cytochrome C by microchip electrophoresis based on an aptamer strategy.

The release of cytochrome C (Cyt C) plays an important role in apoptosis. In this study, selective and sensitive detection of Cyt C based on an aptamer strategy coupled with MCE was developed. Following the binding of a specific aptamer to Cyt C, the aptamer exhibited an irregular state, reducing the binding affinity of a fluorescent probe, and thus preventing the aptamer-Cyt C complexes from detection within the MCE. The height of the detection peak of the residual aptamer linearly decreased, and therefore, the difference in peak height of residual aptamer compared to that of the initial aptamer was used to quantify the captured protein concentration. Experimental conditions such as incubation time, pH, temperature, and ionic strength were optimized. A measurement of Cyt C concentration by MCE was achieved within 135 s, with a limit of detection as low as 0.4 nM. The proposed method has high selectivity and good stability for the detection of Cyt C. The experimental results demonstrate that this method is quick, consumes only a small quantity of sample, is highly selectivity and exhibits high sensitivity.

ECMO for paediatric cardiac arrest caused by bronchial rupture and severe lung injury: a case report about life-threatening rescue at an adult ECMO centre.

BACKGROUND: Bronchial rupture in children is a rare but dangerous complication after chest trauma and is associated with increased mortality. Veno-venous (V-V) extracorporeal membrane oxygenation (ECMO) is reported as one of the treatments for this life-threatening complication. CASE PRESENTATION: A 4-year-old boy with bronchial rupture and traumatic wet lung complicated by cardiac arrest after chest trauma was admitted to an adult ECMO centre. He experienced two cardiac arrests, one before and one during the operation. The total duration of cardiac arrest was 30 min. V-V ECMO was initiated because of severe hypoxia and hypercapnia during the operation. ECMO was performed for 6 days, and mechanical ventilation lasted 11 days. On the 31st day after surgery, he had recovered completely and was discharged without neurological deficit. CONCLUSION: V-V ECMO can be considered for supportive care in children with severe acute respiratory failure after bronchial rupture. In an emergency, V-V ECMO can be carried out effectively in a qualified and experienced adult ECMO centre. However, the application of ECMO in children is different from that in adults and requires more refined management.

[Forecasting of Emission Co-reduction of Greenhouse Gases and Pollutants for the Road Transport Sector in Lanzhou Based on the LEAP Model].

With the continuous increase in transportation activities, the transportation sector has become an important source of global greenhouse gases. In 2019, road vehicles accounted for nearly three-quarters of the CO2 emissions of the entire transportation sector and will be the key to achieving carbon peaks in the transportation sector. At the same time, air pollutants emitted by road vehicles are also one of the threats to the environment and human health. Based on the long-range energy alternatives planning system (LEAP) model, we constructed the baseline (BAU) scenario, low-carbon (LC) scenario, and enhanced low-carbon (ELC) scenario for the development of the road transport sector in Lanzhou from 2015 to 2040 and simulated energy consumption and emission co-reduction of greenhouse gases and pollutants under policies and measures. The results showed that the energy consumption and CO2 emissions of the LC scenario will peak in 2026, whereas those in the ELC scenario will peak in 2020. In these two scenarios, pollutant emissions such as NOx, CO, HC, PM2.5, and PM10 began to decline sharply between 2015 and 2017, and the downward trend will slow down gradually around 2023. Based on the feasibility of measures and the cost of abatement, the LC scenario can be used as a road vehicle carbon peak scenario in Lanzhou. In this scenario, the reduction rates of energy consumption, CO2, NOx, CO, HC, PM2.5, and PM10 emissions will reach -24.17%, -26.57%, -55.38%, -65.91%, -72.87%, -76.66%, and -77.18% compared with those under the BAU scenario by 2040. At present, the road vehicles in Lanzhou City should focus on structural optimization measures such as clean-energy use of public transportation, electrification of small passenger cars, and phasing out old cars, as well as vigorously promoting low-carbon travel and improving energy efficiency accompanying the development of automotive technology. These efforts will effectively control CO2 and pollutant emissions by road vehicles, and carbon peaks will be achieved as soon as possible. In addition, it is necessary to pay attention to the changes in vehicle types during the implementation of these measures, which most contribute CO2 and various pollutants, in order to make the measures more targeted by changing the number or the market share of new energy of focused vehicle types.

Sensitive assay of Escherichia coli in food samples by microchip capillary electrophoresis based on specific aptamer binding strategy.

The rapid and cost-effective detection of bacteria is of great importance to ensuring food safety, preventing food poisoning. Herein, we developed a sensitive detection of Escherichia coli (E. coli) using bacteria-specific aptamer in conjunction with microchip capillary electrophoresis-coupled laser-induced fluorescence (MCE-LIF). Based on the differences between charge to mass ratios of free aptamer and bacteria-aptamer complex, which influence their electrophoretic mobilities, the separation of free aptamers and complex peaks by MCE could be achieved. Under optimal conditions, the sensitive detection of E. coli was achieved with a detection limit of 3.7 × 102 CFU mL-1, at a fast response of 135 s and a short detection length of 2.3 cm. The spiked recovery experiment showed that E. coli could be recovered from spiked drinking water and milk samples with recovery rates of 94.7% and 92.8%, respectively. This work demonstrates that the established detection strategy can be a useful tool for the detection and/or monitoring of E. coli in food and environment.

Simultaneous detection of three foodborne pathogenic bacteria in food samples by microchip capillary electrophoresis in combination with polymerase chain reaction.

A rapid and sensitive PCR based strategy in combination with microchip capillary electrophoresis (MCE) was employed to simultaneously detect three foodborne pathogenic bacteria. Three pairs of primers were specially designed for the amplification of target genes from Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Salmonella enterica serovar Typhimurium (S. Typhimurium). The PCR products along with standard DNA fragments were employed to optimize the separation conditions in MCE. Under optimal conditions, detectable separation of the PCR products (1.6-3.5 ng µL-1) from the three foodborne pathogenic bacteria was achieved within 135 s. The limits of detection of the three bacteria were concluded to be as low as 45 CFU mL-1 for E. coli, 62 CFU mL-1 for S. aureus and 42 CFU mL-1 for S. Typhimurium. The RSD of migration time was in the range of 0.5-0.8%. We conclude that MCE along with PCR holds real potential for rapid analysis and detection of nucleic acids from routine foodborne pathogenic bacteria.

A multiplex PCR amplification strategy coupled with microchip electrophoresis for simultaneous and sensitive detection of three foodborne bacteria.

Foodborne bacteria are some of the most important human pathogens and can cause many diseases. In this study, multiplex PCR amplification combined with microchip electrophoresis (MCE) was studied to simultaneously and sensitively detect Staphylococcus aureus, Proteus mirabilis, and Enterobacter sakazakii. In order to simultaneously and accurately detect the aim bacteria, three pairs of primers were specially designed for the multiplex PCR amplification of the target genes of three bacteria, which were the specific genes corresponding to these bacteria respectively. After the DNA fragments of three bacteria were simultaneously extracted, the multiplex PCR amplification was performed by adding the three pairs of specific primers in the mixed DNA fragments solution. The multiplex PCR products of the three food-borne pathogens were analyzed by MCE and the limits of detection of target DNA fragments were 1.2-2.2ngµL-1, (S/N=3). The limits of detection of the aim bacteria were calculated as 53CFUmL-1 for Enterobacter sakazakii, 32CFUmL-1 for Proteus mirabilis, 28CFUmL-1 for Staphylococcus aureus, respectively. Satisfactory results were obtained when this method was applied to detect the three foodborne bacteria in milk samples. The experimental results show that this method has the advantages of quickness, less sample consumption, high selectivity and high sensitivity.

A sensitive assay based on specific aptamer binding for the detection of Salmonella enterica serovar Typhimurium in milk samples by microchip capillary electrophoresis.

The detection of Salmonella enterica serovar Typhimurium (S. Typhimurium) is very important for the prevention of food poisoning and other infectious diseases. Here we reported a simple and sensitive strategy to test S. Typhimurium by microchip capillary electrophoresis couple with laser-induced fluorescence (MCE-LIF) based on the specific reaction between the bacterium and corresponding aptamers. Based on the differences in charge to mass ratio between bacteria-aptamer complexes and free aptamers, a separation of the complexes and free aptamers could be obtained by MCE. The optimal parameters of the specific reaction including fluorescent dye concentration, Mg2+ concentration, incubation time, and pH of incubation solution were carefully investigated. Meanwhile, a non-specific DNA was exploited as a contrast for the detection of S. Typhimurium. Under the optimal conditions, a rapid separation of the bacteria-aptamer complex and free aptamers was achieved within 135 s with a limit of detection (S/N = 3) of 3.37 × 102 CFU mL-1. This method was applied for the detection of S. Typhimurium in fresh milk samples and a recovery rate of 95.8% was obtained. The experimental results indicated that the specific aptamers are of enough biostability and the established method could be used to analyze S. Typhimurium in foods.

[Protective effects of glutamine on the intestinal mucosal barrier in young rabbits under hemorrhagic shock].

OBJECTIVE: Glutamine (Gln) is now considered as conditionally essential amino acid with many biological activities. This study aimed to investigate whether it has protective effects on the intestinal mucosal barrier in young rabbits under hemorrhagic shock. METHODS: Eighteen young rabbits aged 26 +/- 3 days were randomly assigned into 3 groups: Control (no treatment), Low-dose Gln (L-Gln, 0.5 g/kg daily) and High-dose Gln (H-Gln, 1.0 g/kg daily) treatment groups. Gln was administered by gastric tube daily for 7 days and then hemorrhagic shock was induced by blood withdrawing from femoral artery. Plasma levels of diamine oxidase (DAO) and serum levels of interleukin-8 (IL-8) were measured before shock, and at 2, 6 and 24 hrs after resuscitation. Ileum tissues located approximately 5 cm away from the ileocecal valve was removed for histological examination, lymphocyte distribution, polymorphonuclear (PMN) count and assessing the height, width and surface area of the villi. RESULTS: Plasma levels of DAO and serum levels of IL-8 at 6 and 24 hrs after resuscitation in the L-Gln and the H-Gln groups decreased significantly compared with those of the Control group. L-Gln and H-Gln also resulted in a decrease in the PMN counts and the lymphocyte percentage in the ileum compared with the Control group. Exfoliation and atrophy of villous epithelial cells occurred and the height and surface area of villous were reduced in the Control group. The ileum morphology of the two Gln treatment groups was found to be nearly normal. There were no differences between the L-Gln and the H-Gln groups. CONCLUSIONS: Gln within a therapeutic dose has protective effects on intestinal mucosal barrier in young rabbits under hemorrhagic shock.