Objective To investigate the attributable risk(AR)of Acinetobacter baumannii(AB)infection in criti-cally ill patients.Methods A multicenter retrospective cohort study was conducted among adult patients in inten-sive care unit(ICU).Patients with AB isolated from sterile body fluid and confirmed with AB infection in each cen-ter were selected as the infected group.According to the matching criteria that patients should be from the same pe-riod,in the same ICU,as well as with similar APACHE Ⅱ score(±5 points)and primary diagnosis,patients who did not infect with AB were selected as the non-infected group in a 1:2 ratio.The AR was calculated.Results The in-hospital mortality of patients with AB infection in sterile body fluid was 33.3％,and that of non-infected group was 23.1％,with no statistically significant difference between the two groups(P=0.069).The AR was 10.2％(95％CI:-2.3％-22.8％).There is no statistically significant difference in mortality between non-infected pa-tients and infected patients from whose blood,cerebrospinal fluid and other specimen sources AB were isolated(P＞0.05).After infected with AB,critically ill patients with the major diagnosis of pulmonary infection had the high-est AR.There was no statistically significant difference in mortality between patients in the infected and non-infec-ted groups(P＞0.05),or between other diagnostic classifications.Conclusion The prognosis of AB infection in critically ill patients is highly overestimated,but active healthcare-associated infection control for AB in the ICU should still be carried out.

ObjectiveThe detection of RNA single nucleotide polymorphism (SNP) is of great importance due to their association with protein expression related to various diseases and drug responses. At present, splintR ligase-assisted methods are important approaches for RNA direct detection, but its specificity will be limited when the fidelity of ligases is not ideal. The aim of this study was to create a method to improve the specificity of splintR ligase for RNA detection. MethodsIn this study, a dual-competitive-padlock-probe (DCPLP) assay without the need for additional enzymes or reactions is proposed to improve specificity of splintR ligase ligation. To verify the method, we employed dual competitive padlock probe-mediated rolling circle amplification (DCPLP-RCA) to genotype the CYP2C9 gene. ResultsThe specificity was well improved through the competition and strand displacement of dual padlock probe, with an 83.26% reduction in nonspecific signal. By detecting synthetic RNA samples, the method demonstrated a dynamic detection range of 10 pmol/L-1 nmol/L. Furthermore, clinical samples were applied to the method to evaluate its performance, and the genotyping results were consistent with those obtained using the qPCR method. ConclusionThis study has successfully established a highly specific direct RNA SNP detection method, and provided a novel avenue for accurate identification of various types of RNAs.

Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.

Objective To investigate the effects of exercise and complex environment on lipopolysaccharide(LPS)-induced dopaminergic neuron death in the substantia nigra of midbrain.Methods C57BL/6 mice were divided into control group,LPS group,LPS+swimming group and LPS+complex environment group,with 7 mice in each group.The mice in the LPS group were injected with LPS into the brain to establish an inflammatory model of Parkinson's disease and lived in cages for 2 weeks.Mice in LPS+swimming group were forced to swim for 15 minutes every day for 2 weeks after modeling.The mice in the LPS+complex environment group were placed in a complex environment for 2 weeks after modeling.The control group mice were not treated.After 14 days of modeling,behavioral experiments such as footprint,open field and rotating rod were performed on each group of mice to detect the autonomous exercise ability,exercise balance ability and depression level of mice.The expressions of tyrosine hydroxylase(TH)in substantia nigra was detected by immunohistochemical staining and Western blotting.The expressions of brain-derived neurotrophic factor(BDNF),Caspase-3,interleukin-1β(IL-1β),interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)in the substantia nigra of the midbrain were detected by Western blotting.The transcription levels of IL-1β,IL-6 and TNF-α in substantia nigra were detected by RT-PCR.Results Compared with the control group,the exercise ability and balance ability of mice in LPS group,LPS+swimming group and LPS+complex environment group decreased,the depression level increased(P＜0.001),the number of TH positive neurons and BDNF protein decreased significantly(P＜0.001),and the contents of Caspase-3,IL-1β,IL-6 and TNF-α increased significantly(P＜0.001).Compared with the LPS group,the exercise ability and balance ability of the mice in the LPS+swimming group and the LPS+complex environment group were restored,the depression level decreased significantly(P＜0.01),the survival number of TH positive neurons and the content of BDNF increased significantly(P＜0.01),Caspase-3,IL-1β,IL-6 and TNF-α reduced significantly(P＜0.01),and the phenomenon in the LPS+complex environment group was more significant.Conclusion Exercise and complex environment can inhibit LPS-induced central nervous system inflammation in mice,thereby reducing damage to midbrain substantia nigra neurons,and the inhibitory effect of LPS+complex environment group is more significant.

Objective:To investigate the toxic effect of chlorambucil combined with ibrutinib on mantle cell lymphoma(MCL)cell line Jeko-1 and its related mechanism.Methods:The MCL cell line Jeko-1 was incubated with different concentrations of chlorambucil or ibrutinib or the combination of the two drugs,respectively.CCK-8 assay was used to detect the proliferation of the cells,and Western blot was used to measure the protein expression levels of BCL-2,caspase-3,PI3K,AKT and P-AKT.Results:After Jeko-1 cells were treated with chlorambucil(3.125,6.25,12.5,25,50 μmol/L)and ibrutinib(3.125,6.25,12.5,25,50 μmol/L)alone for 24,48,72h respectively,the cell proliferation was inhibited in a time-and dose-dependent manner.Moreover,the two drugs were applied in combination at low doses(single drug inhibition rate＜50％),and the results showed that the combination of two drugs had a more significant inhibitory effect(all P＜0.05).Compared with the control group,the apoptosis rate of the single drug group of chlorambucil(3.125,6.25,12.5,25,50 μmol/L)and ibutinib(3.125,6.25,12.5,25,50 μmol/L)was increased in a dose-dependent manner.The combination of the two drugs at low concentrations(3.125,6.25,12.5 μmol/L)could significantly increase the apoptosis rate compared with the corresponding concentration of single drug groups(all P＜0.05).Compared with control group,the protein expression levels of caspase-3 in Jeko-l cells were upregulated,while the protein expression levels of BCL-2,PI3K,and p-AKT/AKT were downregulated after treatment with chlorambucil or ibrutinib alone.The combination of the two drugs could produce a synergistic effect on the expressions of the above-mentioned proteins,and the differences between the combination group and the single drug groups were statistically significant(all P＜0.05).Conclusion:Chlorambucil and ibrutinib can promote the apoptosis of MCL cell line Jeko-1,and combined application of the two drugs shows a synergistic effect,the mechanism may be associated with the AKT-related signaling pathways.

Objective:To provide reference for hospital drug selection and clinical rational drug selection,through evaluating the nutritional value of six commonly used balanced compound amino acid injection (BCAA) in clinical practice,including 18AA (250 mL:12.5 g),18AA-I (250 mL:17.5 g),18AA-Ⅱ(250 mL:21.25 g),18AA-IV (250 mL:8.7 g),18AA-V (250 mL:8.06 g),and 18AA-V-SF (250 mL:8.06 g). Methods:Based on the whole egg protein model,the nutritional value of six varieties of BCAA from two aspects were evaluated,including the first limiting amino acid chemical score (CS),value of essential amino acid (EAA) and the comprehensive quality of total EAA (both essential amino acid index and closeness to standard protein). Results:The first limiting amino acid CS value from high to low was 18AA-Ⅱ>18AA>18AA-V=18AA-V-SF>18AA-I=18AA-Ⅳ. Total EAA comprehensive quality:the essential amino acid index from high to low was 18AA-Ⅱ>18AA>18AA-I>18AA-Ⅳ>18AA-V=18AA-V-SF. The closeness to whole egg protein from high to low was 18AA-Ⅱ=18AA=18AA-I>18AA-Ⅳ>18AA-V=18AA-V-SF. Ultimately,the nutritional value of the 6 varieties of BCAA decreased from high to low:18AA-Ⅱ>18AA>18AA-I>18AA-Ⅳ>18AA-V=18AA-V-SF. Conclusions:Among the six varieties of BCAA,18AA-Ⅱ has the highest nutritional value and the highest amino acid content in the same liquid volume,making it the preferred drug for patients with normal liver and kidney function.

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates.Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity.This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes.The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes,and corresponding reference ranges will be established.The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance,with altitude gradients divided into 4 categories:800 m,1 900 m,2 400 m,and 3 500 m,with an anticipated sample size of 170 neonates per altitude gradient.This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.[Chinese Journal of Contemporary Pediatrics,2024,26(4):403-409]

Objective To investigate the effect of dihydromyricetin(DMY)on myocardial oxidative damage in exhaustive exercise mice.Methods C57BL/6 mice were divided into control group,model group,positive control group and low,medium and high dose experimental groups and with 10 mice in each group.Mice in control group and model group were intragastricated with distilled water;20,40 and 80 mg·kg-1 dihydromyricetin were given by gavage in low,medium and high dose experimental groups,while mice in positive control group were intragastricated with 100 mg·kg-1 Vitamin C once a day for 4 weeks.After administration,superoxide dismutase(SOD),malondialdehyde(MDA)and lactate dehydrogenase(LDH)were detected by the kit.The expression of nuclear factor E2-related factor 2(Nrf2)and heme oxygenase-1(HO-1)protein were detected by Western blot.Results SOD levels in control group,model group and low,medium,high dose experimental groups and positive control group were(57.81±6.92),(26.85±2.74),(33.68±4.52),(39.74±3.95),(48.97±4.26)and(39.22±3.54)U·mg-1;MDA were(4.72±0.36),(10.48±1.68),(8.75±0.82),(6.43±0.71),(5.11±0.48)and(6.36±0.64)nmol·mg-1;LDH were(268.71±23.94),(726.58±81.26),(621.32±47.59),(479.12±50.24),(337.91±34.99)and(486.15±50.98)U·L-1;Nrf2 protein expression were 0.75±0.06,0.19±0.02,0.30±0.04,0.47±0.05,0.63±0.06 and 0.49±0.06;the protein expression of HO-1 were 0.83±0.08,0.27±0.05,0.39±0.04,0.52±0.03,0.77±0.07 and 0.55±0.06,respectively.There were statistically significant differences between control group and model group(all P＜0.05);there were statistically significant differences in the above indexes between model group and positive control group,low dose experimental group,medium dose experimental group,high dose experimental group(all P＜0.05).Conclusion Dihydromyricetin can delay myocardial oxidative injury in exhaustive exercise mice,which may be related to Nrf2/HO-1 pathway.

Objective To investigate the effects of verbascoside on oxygen consumption and mitochondrial enzyme activities in skeletal muscle of rats with intense exercise.Methods Fifty SD rats were randomly divided into control group,model group,experimental-L,-M,-H groups.Exercise training was performed in all groups except the control group.The control group and model group were given 2 mL of 0.9％NaCl,the experimental-L,-M,-H groups was given 20,40,80 mg·kg-1·d-1 verbascoside.The activities of Na+/K+-ATP and Ca2+/Mg2+-ATP were detected by kit.Protein expressions of optic atrophy 1(Opa1),mitochondrial fusion(Mfn)1 and Mfn2 were detected by Western blot.Results The Na+/K+-ATP of experimental-L,-M,-H groups,model group and blank group were(2.74±0.44),(3.50±0.38),(4.39±0.41),(2.13±0.32)and(5.75±0.42)U·mg-1;Ca2+/Mg2+-ATP were(4.01±0.32),(4.82±0.79),(6.57±0.70),(3.51±0.35)and(8.92±1.14)U·mg-1;Opa-1 were 0.40±0.05,0.52±0.04,0.69±0.09,0.25±0.06 and 0.78±0.11;Mfn1 were 0.47±0.06,0.59±0.07,0.74±0.08,0.32±0.05 and 0.89±0.12;Mfn2 were 0.51±0.07,0.65±0.06,0.83±0.06,0.35±0.06 and 1.02±0.13,respectively.There was statistical significance between control group and model group(all P＜0.05);there were statistically significant differences in the above indexes between the experimental-L,-M,-H groups and the model group(all P＜0.05).Conclusion Verminoside can improve the oxygen consumption and mitochondrial enzyme activity of skeletal muscle and increase the antioxidant capacity of rats with intense exercise.

Stable isotope tracer metabolomics tracks and analyzes the whole metabolic process of the body through the tracer atoms, which belongs to the frontier technology in the field of biomedicine. This technology is of great significance and value for explaining the pathogenesis of diseases, finding biomarkers of diseases and drug action targets. Taking the mechanism of glucose catabolism disorder in depression as an example, this paper systematically expounds the stable isotope tracer metabolomics technology and its application. The research idea of stable isotope tracer metabolomics based on unmarked metabolomics was put forward, and the research strategy of biological significance interpretation from four dimensions of metabolite isotope abundance, key metabolic enzymes, metabolic flow direction and metabolite flow was given, which broke through the bottleneck of stable isotope tracer metabolomics research technology based on overall animal experiment, and provided scientific basis for the promotion and application of this technology.