Distribution and drug resistance of pathogenic bacteria in emergency patients

BACKGROUND Antibiotic resistance has become a global threat for human health,calling for rational use of antibiotics.AIM To analyze the distribution and drug resistance of the bacteria,providing the prerequisite for use of antibiotics in emergency patients.METHODS A total of 2048 emergency patients from 2013 to 2017 were enrolled.Their clinical examination specimens were collected,followed by isolation of bacteria.The bacterial identification and drug susceptibility testing were carried out.RESULTS A total of 3387 pathogens were isolated.The top six pathogens were Acinetobacter baumannii(660 strains),Staphylococcus aureus(436 strains),Klebsiella pneumoniae(347 strains),Pseudomonas aeruginosa(338 strains),Escherichia coli(237 strains),and Candida albicans(207 strains).The isolation rates of these pathogens decreased year by year except Klebsiella pneumoniae,which increased from 7.1%to 12.1%.Acinetobacter baumannii is a widely-resistant strain,with multiple resistances to imipenem,ciprofloxacin,minocycline and tigecycline.The Staphylococcus aureus had high resistance rates to levofloxacin,penicillin G,and tetracycline.But the susceptibility of it to vancomycin and tigecycline were 100%.Klebsiella pneumoniae had high resistance rates to imipenem,cefoperazone/sulbactam,amikacin,and ciprofloxacin,with the lowest resistance rate to tigecycline.The resistance rates of Pseudomonas aeruginosa to cefoperazone/sulbactam and imipenem were higher,with the resistance rate to amikacin below 10%.Besides,Escherichia coli had high resistance rates to ciprofloxacin and cefoperazone/sulbactam and low resistance rates to imipenem,amikacin,and tigecycline.CONCLUSION The pathogenic bacteria isolated from the emergency patients were mainly Acinetobacter baumannii,Staphylococcus aureus,Klebsiella pneumoniae,Pseudomonas aeruginosa,Escherichia coli,and Candida albicans.The detection rates of drugresistant bacteria were high,with different bacteria having multiple drug resistances to commonly used antimicrobial agents,guiding the rational use of drugs and reducing the production of multidrug-resistant bacteria.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma(HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression, localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 m RNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion; pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion(ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64%(6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.Conclusion HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma(HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression, localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 m RNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion; pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion(ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64%(6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.Conclusion HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma(HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression, localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 m RNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion; pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion(ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64%(6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.Conclusion HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma(HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression, localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 m RNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion; pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion(ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64%(6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.Conclusion HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma(HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression,localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 mRNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion;pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion(ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64%(6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.Conclusion HBV S promoter deletion was found dominantly in HCC tumor tissue. The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus(HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of hepatocellular carcinoma(HCC) patients were screened by PCR and direct sequencing.All patients carried HBV with genotype C,except for one B/C heterozygote.The expression,localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro.The expression of endoplasmic reticulum(ER) GRP78 mRNA was assayed.Results Four patterns of pre-S mutations were identified:pre-S 1 in-frame deletion involving the first start codon;pre-S2 in-frame deletion;pre-S2 start codon mutation with or without in-frame deletion;and S promoter in-frame deletion(ASP).The first two types were evenly found in both tumor and non-tumor tissues.They were rarely present as dominant strains.The last two types were frequently found in the dominant strains in tumor tissues.The overall prevalence of HBV carrying ASP was 17.64%(6/34) in tumor tissues,but none were dominant in nontumor tissues.HBV carrying ASP was unable to produce S protein in vitro.Immunocytofluorescence assay showed that the ASP LHBs mutant aggregated in the cytoplasm,accumulating mainly in the ER.Transient transfection and expression of ASP mutant caused GRP78 up-regulation in vitro.Conclusions HBV S promoter deletion was found dominantly in HCC tumor tissue.The aggregation of mutant large surface proteins in the ER possibly involved in HBV-related HCC.

Hepatitis B Virus S Promoter Deletion in Hepatocellular Carcinoma

Objective To identify the difference and significance of dominant types of hepatitis B virus (HBV) pre-S mutation between liver tumor tissues and paired adjacent non-tumor tissues and to test if the mutations were tumor tissue specific.Methods HBV DNA isolated from 34 paired intratumoral and peritumoral tissues of Hepatocellular Carcinoma (HCC) patients were screened by PCR and direct sequencing. All patients carried HBV with genotype C, except for one B/C heterozygote. The expression,localization and excretion of LHBs mutant carrying pre-S deletions were characterized in vitro. The expression of endoplasmic reticulum(ER) GRP78 mRNA was assayed.Results Four patterns of pre-S mutations were identified: pre-S1 in-frame deletion involving the first start codon; pre-S2 in-frame deletion;pre-S2 start codon mutation with or without in-frame deletion; and S promoter in-frame deletion (ΔSP). The first two types were evenly found in both tumor and non-tumor tissues. They were rarely present as dominant strains. The last two types were frequently found in the dominant strains in tumor tissues. The overall prevalence of HBV carrying ΔSP was 17.64% (6/34) in tumor tissues, but none were dominant in non-tumor tissues. HBV carrying ΔSP was unable to produce S protein in vitro. Immunocytofluorescence assay showed that the ΔSP LHBs mutant aggregated in the cytoplasm, accumulating mainly in the ER. Transient transfection and expression of ΔSP mutant caused GRP78 up-regulation in vitro.

Enhanced carbon capture with motif-rich amino acid loaded defective robust metal-organic frameworks

The use of metal-organic frameworks(MOFs)as solid adsorption materials for carbon capture is promising,but achieving efficient and reversible adsorption with a balance of capacity and selectivity for carbon dioxide(CO_(2))over N_(2) remains a challenge.To take full advantage of the strong channel traffic and robustness of MOFs with relatively small pores,it is highly necessary to employ a defect-engineering strategy to construct a broader channel structure that can facilitate the loading of functional motif-rich amino acids(AAs).This strategy can greatly enhance the CO_(2) adsorption performance of MOF.In this study,motif-rich amino acids are loaded into the defective and robust porous frameworks via combined defect-engineering and post-synthetic methods.The defective Zr/Hf-MOF-808s modified with AAs,especially for the 18 mol%4-nitroisophthalic acid,generated defective products allowing for the loading of L-serine(L-Ser).This modification resulted in a significant improvement in both the adsorption capacity(248%improvement at 298 K,100 kPa)and the selectivity of CO_(2)/N_(2) using the ideal adsorbed solution theory(IAST),with the selectivity increasing to 120.55 and 38.27 at 15 and 100 kPa,respectively,while maintaining good cycling performance.Density functional theory(DFT)simulation,CO_(2) temperature-programmed desorption(CO_(2)-TPD),and in situ Fourier transform infrared spectroscopy(FTIR)were further employed to have a better understanding of the enhanced CO_(2) adsorption capacity.Interestingly,unlike the AAs loaded pristine MOF-808s that showed the best CO_(2) adsorption capacity with the loading of short and small glycine(Gly),the broadened channel size in our work enables the loading of functional motif-rich L-serine,which brings more active binding sites,improving CO_(2) adsorption.

Remote substituent effects on catalytic activity of metal-organic frameworks: a linker orbital energy model

The Hammett equation is commonly used to theoretically depict the remote electronic effects of substituents on catalytic activitiesof metal nodes of metal-organic frameworks (MOFs). However, the application of the theory to MOF catalysts usually encountersproblems because it relies heavily on empirical parameters with unknown transferability. To develop an alternative predictiontheory, the linker orbital energy model has been proposed by density functional theory calculations. The model provides a simplemethod to approximately depict the remote electronic substituent effects on catalytic activities of metal nodes of MOFs, and itsgeneral applicability to MOFs is supported by extensively revisiting the structure-activity relationships reported in the literatures.The model can be used to design catalytic activity of metal nodes of MOFs by engineering the electronic properties of linkers andsubstituents.

Plasmonic nanostructures acting as a light-driven O_(2)-sensitive nitroreductase mimic for enhanced photochemical oxidation of para-aminothiophenol

Nanozymes,as a novel form of enzyme mimics,have garnered considerable interest.Despite overcoming the main disadvantages of their natural analogs,they still face challenges such as restricted mimic types and low substrate specificity.Herein,we introduce a reactive ligand modification strategy to diversify enzyme mimic types.Specifically,we have utilized helical plasmonic nanorods(HPNRs)modified with para-nitrothiophenol(4-NTP)to create an oxygen-sensitive nitroreductase(NTR)with light-controllability.HPNRs act as a light-adjustable source of nicotinamide adenine dinucleotide/nicotinamide adenine dinucleotide phosphate(NAD(P)H),providing photon-generated energetic electrons to adsorbed 4-NTP molecules.In the presence of O_(2),the activated 4-NTP transfers the captured electron to the adsorbed O_(2),mimicking the electron transfer process in its natural counterpart.This enhanced O_(2)activation notably boosts the oxidative coupling of para-aminothiophenol(4-ATP).Density functional theory(DFT)calculations reveal that hot electrons injected into the lowest unoccupied molecular orbital(LUMO)energy level of 4-NTP can be transferred to that of molecular oxygen.In conclusion,our findings underline the potential of the reactive ligand modification strategy in developing new types of enzyme reactions,which opens up promising avenues for the enhancement and diversification of nanozyme functionalities.

Electron and configuration engineering of atomic Cu and multioxidated Cu_(2+1)O centers via gasifiable reductant strategy for efficient oxygen reduction toward Zn-air battery

Efforts in a large number of transition metal-carbon systems are devoted to the development of efficient catalysts for oxygen reduction reaction(ORR).However,unsatisfied O_(2)adsorption and slow reduction of OH*at the active centers hinder the further development of these catalysts.We here report a gasifiable reductant strategy,of which a new Cu-based metal organic framework(MOF:termed NTU-83)nanosheet was co-pyrolyzed with melamine to produce the N-coordinated atomic Cu and multi-oxidated Cu_(2+1)O active centers on the carbon foam with ultrathin skeleton.The engineered electrons and configuration of the active centers boost the catalyst(Cu/NC-1000)to show superior ORR activity(E_(1/2)=0.85 V),excellent stability,and methanol resistance.Further modeling calculation and controlled experiments reveal that the Cu_(2+1)O species play a crucial role in kinetically accelerated adsorption and activation of O_(2),while the N_(4)coordinated atomic Cu facilitates fast reduction of OH*.Such characteristics endow the Zn-air battery that containing Cu/NC-1000 as air cathode to show a high peak power density(138 mW·cm^(−2)),a high specific capacity of 763 mAh·gZn^(−1),and outstanding long-term cycle stability.The plausible mechanism and excellent performance show that gasifiable reductant strategy opens up a new route for regulation of the electronic of active sites but also provides a candidate for the practical application in energy conversion/storage devices.

Layer-by-layer assembled dual-ligand conductive MOF nano-films with modulated chemiresistive sensitivity and selectivity

In this paper,a dual-ligand design strategy is demonstrated to modulate the performance of the electronically conductive metalorganic frameworks(EC-MOFs)thin film with a spray layer-by-layer assembly method.The thin film not only can be precisely prepared in nanometer scale(20-70 nm),but also shows the pin-hole-free smooth surface.The high quality nano-film of 2,3,6,7,10,11-hexaiminotriphenylene(HITP)doped Cu-HHTP enables the precise modulation of the chemiresistive sensitivity and selectivity.Selectivity improvement over 220%were realized for benzene vs.NH3>as well as enhanced response and recovery properties.In addition,the selectivity of the EC-MOF thin film sensors toward other gases(e.g.triethylamine,methane,ethylbenzene,hydrogen,butanone,and acetone)vs.NH3 at room temperature is also discussed.