The role of TLR4/MyD88/NF-κB in the protective effect of ulinastatin on the intestinal mucosal barrier in mice with sepsis.

OBJECTIVE: To investigate the effect of the TLR4/MyD88/NF-κB (Toll-like receptor 4/myeloid differentiation factor/nuclear factor kappa B) signalling pathway on the protective effect of ulinastatin on the intestinal mucosal barrier in mice with sepsis. METHODS: A mouse model of sepsis was established by classical caecal ligation and perforation. Forty-four SPF C57BL/6 mice were randomly divided into the following four groups with 11 mice in each group: the control group (Con group), ulinastatin group (Uti group), Uti + LPS (lipopolysaccharide, LPS) group (Uti + LPS group) and LPS group. Mice in the Con group and Uti group received saline or ulinastatin injected 2 h after modelling; Mice in the Uti + LPS group received LPS injected 0 h after modelling, other procedures were the same as in the Uti group; Mice in the LPS group received LPS only. At 48 h after surgery, the levels of TNF-α (tumour necrosis factor-α, TNF-α), IL-6 (interleukin-6, IL-6) and IL-1ß (interleukin-1ß, IL-1ß) in vein, and the expression of TLR4, MyD88 and NF-κB mRNA in small intestinal mucosa tissues using ELISA and RT‒PCR. RESULTS: The pathological specimens showed increased inflammatory injury in the Con and LPS groups, while these injuries and changes improved in the Uti group. The scores of intestinal mucosal injury at 48 h of Uti injection were significantly lower than those of the Con group (P < 0.001), while the scores of intestinal mucosal injury of Uti + LPS were significantly higher than those of the Uti group (P = 0.044). The expression of TNF-α, IL-6 and IL-1ß in the Uti decreased significantly at 48 h after surgery than that in the Con group (P = 0.001, P = 0.014, P = 0.004), while the expression of TNF-α, IL-6 and IL-1ß in the Uti + LPS group increased significantly after surgery than that in the Uti group (P = 0.026, P = 0.040, P = 0.039). The expression of TLR4, MyD88 and NF-κB mRNA in the Uti group decreased significantly compared with that in the Con group (P = 0.001, P = 0.021, P = 0.007), while the expression of TLR4, MyD88 and NF-κB mRNA in the Uti + LPS group was higher than that in the Uti group (P = 0.023, P = 0.040, P = 0.045). CONCLUSION: These findings indicate that the protective effect of ulinastatin on the intestinal mucosal barrier against sepsis may be mediated through the TLR4/MyD88/NF-κB pathway.

A Variant of IL1B Is Associated with the Risk and Blood Lipid Levels of Myocardial Infarction in Eastern Chinese Individuals.

In this study, we determined to interpret the effects of the interleukin (IL)1B gene rs1143634 C/T polymorphism on myocardial infarction (MI) risk. This study, conducted in a Chinese Han population, recruited 369 MI patients and 465 controls. The variant of IL1B gene (rs1143634 C/T polymorphism) was genotyped by PCR-RFLP method. In this study, a significant link was shown between the IL1B rs1143634 C/T polymorphism and MI risk. We found that the IL1B rs1143634 C/T polymorphism enhanced the risk of MI in this population. Subgroup analysis detected that the IL1B rs1143634 C/T polymorphism associated with MI susceptibility in males, smokers, and individuals with diabetes mellitus. In addition, the IL1B rs1143634 C/T polymorphism was related with the levels of blood lipids including low-density lipoprotein (LDL), and total cholesterol (TC). This study uncovers that the IL1B rs1143634 C/T polymorphism may associate with the risk and blood lipid levels of MI in an Eastern Chinese Han population.Abbreviations: MI: myocardial infarction; IL-1: Interleukin-1; SNP: single nucleotide polymorphism; BMI: Body Mass Index; HDL: high-density lipoprotein; TC: total cholesterol; TG: triglyceride; LDL: low-density lipoprotein; PCR: polymerase chain reaction; 95% CI: 95% confidence interval; OR: odds ratio.

Xanthones from Calophyllum Polyanthum Wallich ex Choisy with CYP1 Enzymes Inhibitory Activity.

Three new xanthone compounds, 1,3,5-trihydroxy-2-(2-hydroxy-3-methylbut-3-enyl)-4-(3-methylbut-2-enyl)xanthone (1), toxyloxanthone E (2), dehydrocycloguanandin B (3) along with 15 known xanthones (4-18) were isolated from the aerial parts of Calophyllum polyanthum Wall. ex Choisy. Their structures were fully characterised using spectroscopic data, as well as comparison with the previous literature data. All isolated compounds had inhibitory effects against CYP1A1, CYP1A2 and CYP1B1 enzymes at working concentration of 10 µM, 1 µM and 10 µM, respectively. Among them, compounds 10, 11, and 12 exhibited better CYP1A2 enzyme inhibitory effects than that of the positive control α-naphthoflavone, with 51.05 %, 56.82 % and 44.93 % inhibition, respectively.

Enantioselective decarboxylative Mannich reaction of ß-keto acids with C-alkynyl N-Boc N,O-acetals: access to chiral ß-keto propargylamines.

The chiral keto-substituted propargylamines are an essential class of multifunctional compounds in the field of organic and pharmaceutical synthesis and have attracted considerable attention, but the related synthetic approaches remain limited. Therefore, a concise and efficient method for the enantioselective synthesis of ß-keto propargylamines via chiral phosphoric acid-catalyzed asymmetric Mannich reaction between ß-keto acids and C-alkynyl N-Boc N,O-acetals as easily available C-alkynyl imine precursors has been demonstrated here, affording a broad scope of ß-keto N-Boc-propargylamines in high yields (up to 97%) with generally high enantioselectivities (up to 97 : 3 er).

Penisarins A and B, Sesquiterpene Coumarins Isolated from an Endophytic Penicillium sp.

Penisarins A (1) and B (2), sesquiterpene coumarins with an unusual tricyclic sesquiterpene system, were isolated from endophytic Penicillium sp. KMU18029. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Compound 2 showed significant cytotoxicities against two human cancer cell lines, HL-60 and SMMC-7721, with IC50 values of 3.6 ± 0.2 and 3.7 ± 0.2 µM, respectively.

Novel Isochroman Dimers from Stachybotrys sp. PH30583: Fermentation, Isolation, Structural Elucidation and Biological Activities.

The rare anishidiol and five new isochromans, including three novel dimers with unprecedented skeletons, were isolated from Stachybotrys sp. PH30583. Their structures were determined by spectral analyses. The bioactivities of these compounds were also investigated. The dimers (6-10) inhibited acetylcholinesterase at 50 µM, but the monomers did not. To investigate the biogenesis of the novel dimers, a time-course investigation of metabolite production was undertaken.

Recent Advances in Conotoxin Classification by Using Machine Learning Methods.

Conotoxins are disulfide-rich small peptides, which are invaluable peptides that target ion channel and neuronal receptors. Conotoxins have been demonstrated as potent pharmaceuticals in the treatment of a series of diseases, such as Alzheimer's disease, Parkinson's disease, and epilepsy. In addition, conotoxins are also ideal molecular templates for the development of new drug lead compounds and play important roles in neurobiological research as well. Thus, the accurate identification of conotoxin types will provide key clues for the biological research and clinical medicine. Generally, conotoxin types are confirmed when their sequence, structure, and function are experimentally validated. However, it is time-consuming and costly to acquire the structure and function information by using biochemical experiments. Therefore, it is important to develop computational tools for efficiently and effectively recognizing conotoxin types based on sequence information. In this work, we reviewed the current progress in computational identification of conotoxins in the following aspects: (i) construction of benchmark dataset; (ii) strategies for extracting sequence features; (iii) feature selection techniques; (iv) machine learning methods for classifying conotoxins; (v) the results obtained by these methods and the published tools; and (vi) future perspectives on conotoxin classification. The paper provides the basis for in-depth study of conotoxins and drug therapy research.

External application of traditional Chinese medicine in the treatment of bone cancer pain: a meta-analysis.

BACKGROUND: Bone cancer pain presents a clinical challenge with limitations of current treatments. Many patients seek additional therapies that may relieve pain. Many external applications of traditional Chinese medicines (EAs-TCMs) have been evaluated in clinical trials, but fewer are known about them outside of China. The objective of this study is to assess the efficacy for bone cancer pain. METHODS: A systematic literature search was conducted in seven databases until December 2014 to identify randomized controlled trials (RCTs) about EAs-TCMs in the treatment of bone cancer pain. The primary outcome was total pain relief rate. The secondary outcomes were adverse events at the end of treatment course. The methodological quality of RCTs was assessed independently using six-item criteria according to the Cochrane Collaboration. All data were analyzed using Review Manager 5.2.0. We included any RCTs evaluating an EA-TCM for the treatment of bone cancer pain. We conducted a meta-analysis. RESULTS: We included six RCTs with 534 patients. In general, the reporting of methodological issues was poor. Compared with morphine sulfate sustained release tablets (MSSRTs) or radiotherapy or bisphosphonates, we analyzed data from five trials reporting on complete response effect score (relative risk (RR) = 5.38, 95% confidence interval (CI) = 2.80-10.31, P < 0.00001) and partial response (RR = 1.18, 95% CI = 1.02-1.37, P = 0.02) and six trials reporting on total pain relief rate (RR = 1.49, 95% CI = 1.43-1.67, P < 0.00001). Six RCTs showed significant effects of EA-TCM for improving pain relief in patients with bone cancer pain. In addition, no severe adverse events were found. CONCLUSION: This systematic review showed positive but weak evidence of EA-TCM for bone cancer pain because of the poor methodological quality and the small quantity of the included trials. Future rigorously designed RCTs are required.

High endothelial venules proportion in tertiary lymphoid structure is a prognostic marker and correlated with anti-tumor immune microenvironment in colorectal cancer.

BACKGROUND: High endothelial venules (HEV) and tertiary lymphoid structures (TLS) are associated with clinical outcomes of patients with colorectal cancer (CRC). However, because HEV are components of TLS, there have been few studies of the role of the HEV proportion in TLS (HEV/TLS). This study investigated the role of the HEV/TLS and its relationship with the tumor immune microenvironment in CRC. METHODS: A retrospective analysis of 203 cases of tissue pathologically diagnosed as CRC after general surgery was performed at the First Affiliated Hospital of Jinan University from January 2014 to July 2017. Paraffin sections were obtained from the paracancerous intestinal mucosal tissues. The area of HEV and TLS and immune cells were detected by immunohistochemistry. We further divided the positive HEV expression group into the high HEV/TLS group and the low HEV/TLS group by the average area of HEV/TLS. After grouping, the data were also analyzed using the chi-square test, Kaplan-Meier method, and univariate and multivariate Cox proportional risk regression analyses. A correlation analysis of the HEV/TLS and immune cells as well as angiogenesis was performed. RESULTS: Patients with a high HEV/TLS in CRC tissue were associated with longer OS, DFS and lower TNM stage. Meanwhile, CRC tissue with a high HEV/TLS showed a greater ability to recruit the CD3+ T cells, CD8+ T cells and M1 macrophages and correlated with less angiogenesis. Conclusively, high HEV/TLS links to the favorable prognosis of CRC patients and correlated with anti-tumor immune microenvironment, which can be a potential biomarker for prognosis of CRC patients. CONCLUSION: A high HEV/TLS is associated with a favorable prognosis for CRC and is correlated with the anti-tumor immune microenvironment. Therefore, it is a potential biomarker of the CRC prognosis.KEY MESSAGESHigh HEV/TLS is associated with a favorable prognosis for CRC.High HEV/TLS correlated with the anti-tumor immune microenvironment of CRC and can serve as a novel prognostic biomarker.

A Comparative Study on Sedation Efficacy Between General and Regional Anesthesia with Dexmedetomidine in Patients Under Maxillofacial Surgery.

BACKGROUND AND OBJECTIVE: Securing the airway in the surgery of maxillofacial disorders and traumas is fundamental during the operation. The present study aims to investigate the beneficial sedative effects of dexmedetomidine (DEX) in patients who underwent maxillofacial surgery with regional anesthesia compared to general anesthesia. METHODS: Fifty patients, aged 20-45 years old were randomly divided into two groups of regional anesthesia (RA) and general anesthesia (GA) (each n=25). The group RA received regional block with sedation (DEX: 1 µg/kg infused over 10 min followed by the maintenance dose of 0.5 µg/kg/h) and the group GA underwent general anesthesia (DEX: 0.1 µg/kg/min over 10 min followed by 0.4-0.7 µg/kg/h). Postoperative pain scores, anesthesia outcomes, hemodynamic parameters, the time of the post-anesthesia care unit (PACU) discharge and intra and postoperative complications were comparatively assessed in both groups. RESULTS: The baseline characteristics of the patients (age, gender, BMI, and ASA physical status) showed no differences between the two groups (P>0.05). Although the duration of surgery and recovery time showed no differences between the groups, the duration of anesthesia and extubation time was remarkably lower in the RA group than in the GA group (P<0.01). Administration of nerve blocks demonstrated less pain and longer sleep time in the postoperative phase as compared to the GA group. Heart rate and mean arterial blood pressure were significantly less in the RA group at the end of the loading dose of DEX and incision time (P<0.05). SpO2, respiration rate and Ramsay sedation scale did not exhibit any significant differences between the two groups at all-time points (P>0.05). No significant differences were observed with regard to the adverse events between the two groups (P>0.05). CONCLUSIONS: Although our findings revealed that both methods are suitable and safe methods for maxillofacial surgery, the outcomes of anesthesia with regional block and sedation include less pain in the postoperative phase, shorter extubation time and earlier discharge from the PACU demonstrated that this method is more reliable for maxillofacial surgery. Further controlled studies are needed to compare the effectiveness and safety profiles of two RA and GA techniques and also to compare DEX with other anesthetic agents to achieve optimum outcomes in maxillofacial surgeries.

Associations of CD14 variants with the triglyceride levels and risk of myocardial infarction in an Eastern Chinese Han population.

BACKGROUND: CD14 is crucial in the progression of myocardial infarction (MI). Several studies have explored the association between the risk of MI and the CD14 C-260 T polymorphism, but have reported inconsistent results. METHODS: This study analyzed the association of the CD14 C-260 T polymorphism with susceptibility to MI. Totally, 240 MI patients and 298 normal subjects were included. The association between MI risk and the target polymorphism was assessed using 95% confidence intervals and odds ratios obtained through logistic regression. RESULTS: The T allele of the CD14 C-260 T polymorphism was linked with an elevated risk of MI in Chinese Han people; subgroup analysis indicated that this effect was associated with smoking, male gender, and hypertension. In addition, the data revealed that different genotype carriers of the CD14 C-260 T polymorphism showed significantly distinct TG levels in MI patients. CONCLUSION: Totally, the T allele of the CD14 C-260 T polymorphism is associated with an elevated risk of MI.

MitoQ inhibits hepatic stellate cell activation and liver fibrosis by enhancing PINK1/parkin-mediated mitophagy.

Mitophagy affects the activation of hepatic stellate cells (HSCs). Mitochondria-targeted ubiquinone (MitoQ) is a mitochondria-targeted antioxidant that reduces the production of intracellular reactive oxygen species (ROS). However, its relationship with mitophagy remains unclear. This study evaluated mitophagy during HSC activation and the effects of MitoQ on mitophagy in cell culture and in an animal model of the activation of HSCs. We found that MitoQ reduced the activation of HSCs and alleviated hepatic fibrosis. PINK1 (PTEN-induced putative kinase 1) is a putative serine/threonine kinase located in the mitochondria's outer membrane. While the activation of primary HSCs or LX-2 cells was associated with reduced PINK1/parkin-mediated mitophagy, MitoQ reduced intracellular ROS levels, enhanced PINK1/parkin-mediated mitophagy, and inhibited the activation of HSCs. After knocking down the key mitophagy-related protein, PINK1, in LX-2 cells to block mitophagy, MitoQ intervention failed to inhibit HSC activation. Our results showed that MitoQ inhibited the activation of HSCs and alleviated hepatic fibrosis by enhancing PINK1/parkin-mediated mitophagy.

Fluorescent triphenyl substituted maleimide derivatives: synthesis, spectroscopy and quantum chemical calculations.

In this paper we describe a semi-empirical quantum method for predicting the wavelength of maximum fluorescence excitation and emission for several known and new maleimide derivatives. All new maleimides, containing a N-Benzyl attachment, were successfully synthesised via a tandem Suzuki reaction with aryl boronic acids containing either an electron donating, electron withdrawing functional groups. Absorption and emission spectra calculated using the semi-empirical AM1 method with excited state ZINDO calculations proved more reliable than either Hartree-Fock Configuration interaction or time dependent density functional methods. Calculated absorption and emission wavelengths were compared with 26 experimental spectra from known or newly synthesised maleimides and found to have provide reasonable predictions, with an average deviation of less the 6% for absorption maxima and less than 4% for emission peaks. The described method provides a strong benchmark for the accuracy that can be expected from theoretical predictions of fluorescence spectra.

MicroRNA-20b-5p regulates propofol-preconditioning-induced inhibition of autophagy in hypoxia-and-reoxygenation-stimulated endothelial cells.

Ischemia-reperfusion (IR) injury is a major cause of clinical emergencies during and after surgical procedures. Propofol protects the heart from cardiovascular IR injury by inhibiting autophagy. MicroRNAs (miRNAs) participate in anesthetic-regulated cardiovascular injury. MiR-20b-5p targets unc-51-like autophagy activating kinase 1 (ULK1). Its role in propofol-modulated cardiovascular IR injury remains unclear, however. In this study, we used an in vitro model of hypoxia-reoxygenation (HR)-induced injury to human umbilical vein endothelial cells (HUVECs) to determine the protective effect of miR-20b-5p in cells preconditioned with propofol. We found that miR-20b-5p was significantly higher and ULK1 was lower in propofol-preconditioned HUVECs with HR injury than in HUVECs with HR injury only. Additionally, miR-20b-5p overexpression increased cell viability and repressed autophagy and apoptosis more in propofol-preconditioned HUVECs with HR injury than in HUVECs with HR injury only. A luciferase reporter assay confirmed the target reaction between miR-20b-5p and ULK1. Overexpression of ULK1 restrained the protective effect of miR-20b-5p in propofol-preconditioned HUVECs with HR injury. In conclusion, our results indicate that propofol inhibits autophagic cell death via the miR-20b-5p-ULKI axis and that ULK1 may be a therapeutic target for cardiovascular IR injury.

Virtual Screening for Type II B Inhibitors of B-RafV600E Kinase.

BACKGROUND: B-RafV600E kinase was identified as an important target in current cancer treatment, and the type II B inhibitors show good qualities in preclinical studies. Therefore, it is very important to discover novel II B inhibitors of B-RafV600E kinase. METHODS: In order to discover novel II B inhibitors of B-RafV600E kinase, virtual screening against ZINC database was performed by using a combination of pharmacophore modelling, molecular docking, 3DQSAR model and binding free energy (ΔGbind) calculation studies. The inhibitory activities against A375 cell lines of the hit compounds were tested by using MTT assay. RESULTS: Five promising hit compounds were obtained after screening, and all the five hit compounds showed good inhibitory rates against A375 cell lines. CONCLUSION: The combined approach of the virtual screening in our work is effective, which can be used to discover novel inhibitors with a new skeleton. In addition, the five compounds obtained from the screening showed good inhibitory rates against A375 cell lines, which can be considered to develop new II B inhibitors of B-RafV600E kinase.

Complete mitochondrial genome and the phylogenetic position of the Sphaeroma sp. (Crustacea, Isopod, Sphaeromatidae).

The complete mitogenome of Sphaeroma sp. (Crustacea, Isopod, Sphaeromatidae) was determined in this study. The total length of mitogenome was 15,839 bp, and contained 13 protein-coding genes, 21 tRNA genes, 2 rRNA genes, 1 control region, and 2 unknown fragments which longer than 200 bp. The nucleotide composition was 25.80% A, 16.56% C, 25.94% G and 31.67% T. Six initiation codons (ATA, ATC, ATG, ATT, ACG, GTG) and three termination codons (TAA, TAG, TA-) were used in the protein-coding genes. The length of tRNA genes ranged from 52 to 65 bp, and tRNA-Arg was not identified. The phylogenetic result showed Sphaeroma sp. was closely related to Sphaeroma terebrans with high bootstrap value supported.

Eugenol attenuates the inflammation of Fusarium-induced keratitis through PI3K/AKT signaling pathway / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the protective effect of eugenol against Fusarium solani(F.solani)-induced fungal keratitis(FK)in mice and to preliminarily explore possible underlying mechanisms.METHODS: A modified epifluorescence microscopy method was used to prepare the FK mouse model. An equal amount of DMSO(0.05%)was applied to the conjunctiva of the right eye of rats in the dimethyl sulfoxide(DMSO)group. The eugenol group was prepared by applying eugenol(160 μg/mL)to the conjunctival sac of the right eye of mice. The insulin-like growth factor-1(IGF-1)group was coated with the PI3K/AKT pathway activator IGF-1(10 nmol/mL)in the conjunctival sac of the right eye in addition to the administration of eugenol. The corneal morphology was observed under a slit-lamp microscope on days 1, 3, and 5 of inoculation with F.solani suspension, respectively. Hematoxylin eosin(HE)staining was used to assess corneal histopathological damage. The bacterial load of corneal tissue was determined. Enzyme-linked immunosorbent assay and Western blot were used to analyze the levels of inflammatory mediators interleukin-6(IL-6)and interleukin-1β(IL-1β)and the expression of PI3K/AKT pathway proteins.RESULTS: Eugenol treatment improved the morphological symptoms of keratitis and inflammatory response in FK mice, and reduced corneal pathologic tissue damage and fungal load. At 3 d after F.solani infection, corneal tissue IL-6 levels were significantly higher and IL-1β levels were significantly lower in the eugenol group compared with the DMSO group(both P&#x003C;0.05); corneal tissue IL-6 levels were significantly higher and IL-1β levels were significantly lower in the eugenol group than in the IGF-1 group(both P&#x003C;0.05). At 5 d after infection, both IL-6 and IL-1β levels in corneal tissue of the eugenol group were significantly lower than those of the DMSO and IGF-1 groups(P&#x003C;0.05); compared with the DMSO group, the expression of p-PI3K and p-Akt in the corneal tissues of the eugenol group was significantly reduced(P&#x003C;0.05); the expression of p-PI3K and p-Akt in corneal tissues was significantly lower in the eugenol group than that of the IGF-1 group(both P&#x003C;0.05).CONCLUSION: Eugenol may attenuate F.solani-induced corneal inflammation by inhibiting the PI3K/AKT pathway, and it has a protective effect against F.solani keratitis in mice.

Study on spleen strengthening effects and mechanisms of Atractylodes chinensis and Atractylodes coreana / 中国药理学通报

Aim To analyze the differences in plasma biomarkers and metabolic pathways between Atractylodes chinensis and Atractylodes coreana after intervention in spleen deficiency rats, and discuss the spleen strengthening mechanism of the two from a non targeted metabolomics perspective. Methods A spleen deficiency model was established in SD rats using a composite factor method of improper diet, excessive fatigue, and bitter cold diarrhea. To determine the content of gastrointestinal and immunological indicators, UHPLC-QE-MS technology was used, combined with principal component analysis (PC A) and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) methods to search for biomarkers in plasma of spleen deficiency rats, and metabolic pathways were induced using the Pathway database. Results After administration of Atractylodes chinensis and Atractylodes coreana, various indicators in plasma of spleen deficiency rats showed varying degrees of regression. Metabolomics analysis showed that Atractylodes chinensis and Atractylodes coreana respectively recalled 70 and 82 plasma differential metabolites. Atractylodes chinensis mainly regulated two metabolic pathways : "Glycine, serine, and threonine metabolism, and "Thiamine metabolism". Atractylodes coreana mainly regulated five metabolic pathways, "Glycine, serine, and threonine metabolism", "Thiamine metabolism, "Pyrimidine metabolism", "Butanoate metabolism", and "Riboflavin metabolism". Conclusions Both Atractylodes chinensis and Atractylodes coreana have certain regulatory effects on spleen deficiency rats, and their mechanism of action may be related to regulating metabolic pathways such as "Glycine, serine, and threonine metabolism, and "Thiamine metabolism"in spleen deficiency.

Arrhythmia classification method based on genetic algorithm optimization of C-LSTM model / 中国医学物理学杂志

A GC-LSTM model is proposed based on the characteristics of global optimization of genetic algorithm.The model automatically and iteratively searches the optimal hyper-parameter configuration of the C-LSTM model through the genetic algorithm of a specific genetic strategy,and it is configured using the genetic iteration results and validated on the MIT-BIH arrhythmia database according to the classification criteria of the Association for the Advancement of Medical Instrumentation.The testing shows that the classification accuracy,sensitivity,accuracy and F1 value of GC-LSTM model are 99.37%,95.62%,95.17%and 95.39%,respectively,higher than those of the manually established model,and it is also advantageous over the existing mainstream methods.Experimental results demonstrate that the proposed method can achieve better classification performance while avoiding a large number of experimental parameters.

Establishment of a method for rapid detection of the minimum inhibitory concentration of imipenem in KPC-producing Klebsiella pneumoniae based on ompK36 mutation / 中华检验医学杂志

Objective:To establish a rapid method to detect the minimum inhibitory concentration (MIC) of imipenem in Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) based on ompK36 gene′s GD mutation. Methods:This was a methodological evaluation study. A total of 258 isolates of Klebsiella pneumoniae were collected from Lishui Municipal Central Hospital from March 2011 to December 2019. Porin gene ompK36 and carbapenemase genes blaKPC, blaNDM, blaIMP and blaOXA-48 were amplified by PCR and confirmed by sequencing. The MIC was detected and confirmed by microbroth dilution susceptibility test, and the corresponding patterns of genotype and MIC were constructed. Based on the patterns, a method for rapid detection of imipenem MIC by real-time fluorescence PCR (RT-PCR) was designed and established. The 159 isolates of non-repetitive Klebsiella pneumoniae collected by Lishui Disease Prevention and Control Center (CDC) from 2017 to 2019 were used for further verification. The sensitivity and specificity were calculated by fourfold table. Kappa test was used to compare the consistency between RT-PCR and microbroth dilution susceptibility test. Results:Among 258 isolates, 109 isolates did not carry carbapenemase gene, 65 isolates carried ompK36 gene GD mutation, 127 isolates carried blaKPC, 15 isolates carried blaNDM, 9 isolates carried blaIMP, and blaOXA-48 was not detected. With mircobroth dilution susceptibility test as the standard, there were 3 corresponding patterns between the drug resistance gene and the imipenem MIC of Kp: when all the 4 carbapenemase genes were negative, MIC≤1 mg/L, the sensitivity was 100% (107/107) and the specificity was 98.4% (125/127); when blaKPC was positive and ompK36 gene GD mutation was negative, 4 mg/L≤MIC≤16 mg/L, the sensitivity was 88.2% (60/68) and the specificity was 98.8% (164/166); when blaKPC and ompK36 gene GD mutation were both positive, MIC≥32 mg/L, the sensitivity was 96.6% (57/59) and the specificity was 96.6% (169/175). RT-PCR detected blaKPC, blaNDM, blaIMP, blaOXA-48 genes accurately.The RT-PCR results of ompK36 gene GD mutation in the KPC-producing isolates were 100% consistent with the sequencing results. In the 159 isolates from Lishui CDC, the sensitivity and specificity of imipenem MIC detected by RT-PCR were higher than 95% in all 3 patterns with mircobroth dilution susceptibility test as the standard, and Kappa value was 0.971. Conclusion:The RT-PCR based on ompK36 gene GD mutation was helpful to quickly determine the MIC range of imipenem in KPC-Kp.