Mitochondrial damage-associated molecular patterns: A new insight into metabolic inflammation in type 2 diabetes mellitus.

The pathogenesis of diabetes is accompanied by increased levels of inflammatory factors, also known as "metabolic inflammation", which runs through the whole process of the occurrence and development of the disease. Mitochondria, as the key site of glucose and lipid metabolism, is often accompanied by mitochondrial function damage in type 2 diabetes mellitus (T2DM). Damaged mitochondria release pro-inflammatory factors through damage-related molecular patterns that activate inflammation pathways and reactions to oxidative stress, further aggravate metabolic disorders, and form a vicious circle. Currently, the pathogenesis of diabetes is still unclear, and clinical treatment focuses primarily on symptomatic intervention of the internal environment of disorders of glucose and lipid metabolism with limited clinical efficacy. The proinflammatory effect of mitochondrial damage-associated molecular pattern (mtDAMP) in T2DM provides a new research direction for exploring the pathogenesis and intervention targets of T2DM. Therefore, this review covers the most recent findings on the molecular mechanism and related signalling cascades of inflammation caused by mtDAMP in T2DM and discusses its pathogenic role of it in the pathological process of T2DM to search potential intervention targets.

Use of 3D echocardiography facilitates analysis of thrombolytic efficacy in patients with persistent atrial fibrillation.

ABSTRACT: This study seeks to identify the anticoagulant efficacy of rivaroxaban treatment on thrombi detected using echocardiography of the left atrial appendage in 275 patients with persistent atrial fibrillation (AF). During follow-up after 9 to 24 weeks of Rivaroxaban treatment, patients were divided into 'effective group' (n = 143) and 'ineffective group' (n = 132) according to the thrombolytic effect of the drug. Left atrial diameter (LAD), left atrial ejection fraction (LAEF), left ventricular ejection fraction (LVEF), mean diameter of left atrial appendage (LAADmean), angle between left atrial appendage and left atrial (LAA-A), velocity of blood flow in left atrial appendage (LAA-v) and thrombus size were compared before and after drug administration. Following treatment, LAEF, LVEF and LAA-v values were greater and LAD and LAADmean values were lower in the effective (P<0.05). Logistic regression analysis showed significant correlations of LAD, LAEF, LVEF, LAA-A and LAA-v with anticoagulant efficacy (P<0.05). The efficacy of Rivaroxaban in treatment of left atrial auricular thrombosis in patients with persistent AF was correlated with LAD, LAEF, LVEF, LAA-A and LAA-v. Multivariate logistic regression analysis further revealed LAEF (OR 1.7, 95% CI 0.45-16.9, P=0.008), 3D-EF (OR 6.4, 95% CI 1.06-16.9, P=0.039), and left ventricular global longitudinal strain (GLS) (OR 18.0, 95% CI 1.38-35.68, P=0.028) as factors related to left atrial appendage thrombus. Echocardiography with global longitudinal strain assessment could be effectively utilized to evaluate the functional parameters of LAA and thus aid in predicting the safety of Rivaroxaban as an anticoagulation agent.

Boryl Radical as a Catalyst in Enabling Intra- and Intermolecular Cascade Radical Cyclization Reactions: Construction of Polycyclic Molecules.

Cascade radical cyclization constitutes an atom- and step-economic route for rapid assembly of polycyclic molecular skeletons. Although an array of redox-active metal catalysts has recently shown robust applications in enabling various catalytic cascade radical processes, the use of free organic radical as the catalyst, which is capable of triggering strategically distinct cascades, has rarely been developed. Here, we disclosed that the benzimidazolium-based N-heterocyclic carbene (NHC)-boryl radical is capable of catalyzing cascade cyclization reactions in both intra- and intermolecular pathways, assembling [5,5] fused bicyclic and [6,6,6] fused tricyclic molecules, respectively. The catalytic reactions start with the chemo- and regioselective addition of the boryl radical catalyst to a tethered alkene or alkyne moiety, followed by either an intramolecular formal [3+2] or an intermolecular [2+2+2] cycloaddition process to construct bicyclo[3.3.0]octane or tetrahydrophenanthridine skeletons, respectively. Eventually, a ß-elimination occurs to release the boryl radical catalyst, completing a catalytic cycle. High to excellent diastereoselectivity is achieved in both catalytic reactions under substrate control.

[An experimental study of acute toxicity and pharmacology of fermented Platycodonis Radix].

This study investigated the acute toxicity of fermented Platycodonis Radix on mice and its effect on coughing in mice infected with Mycoplasma pneumoniae. The maximum dosage(MAD) was used in the acute toxicity experiment on mice to observe the signs of mice. After 14 days, dissection, blood biochemical examination, and pathological tissue section observation were conducted. In the pharmacological experiment of fermented Platycodonis Radix, 60 healthy BALB/c mice, 30 males and 30 females, were randomly divided into a blank group, a model group, a carbetapentane group(0.013 g·kg~(-1)·d~(-1)), and high-, medium-, and low-dose fermented Platycodonis Radix groups(5.2, 2.6, and 1.3 g·kg~(-1)·d~(-1)), with 10 mice in each group. Except for the blank group, the mice in the other five groups underwent model induction by intranasally instilling 20 µL of 1×10~6 CCU M. pneumoniae for 3 days, and the mice in each group were orally administered the corresponding drugs for 7 days. Cough induction experiment was conducted to observe and record the cough latency and total cough count within 3 min for each group. Hematoxylin-eosin(HE) staining and Masson staining were used to observe the pathological changes in lung tissues. Immunohistochemistry was performed to observe the protein expression of transient receptor potential A1(TRPA1), calcitonin gene-related peptide(CGRP), and substance P(SP) in the lung tissues of mice in each group. Real-time fluorescence-based quantitative polymerase chain reaction(qRT-PCR) was used to elucidate the changes in the mRNA levels of cough-related factors TRPA1, CGRP, and SP in mice treated with fermented Platycodonis Radix. No mice died in the acute toxicity experiment, and there were no changes in general behavior and major organ histopathological examinations. Compared with the blank group, there were no statistically significant differences in blood biochemical indexes. In the pharmacological experiment of fermented Platycodonis Radix, compared with the model group, the high-and medium-dose fermented Platycodonis Radix groups showed improved lung tissue structure of mice, with clear structure and regular tissue morphology. The qRT-PCR and immunohistochemical detection showed a decrease in the expression of TRPA1, CGRP, and SP in the fermented Platycodonis Radix groups. Fermented Platycodonis Radix can exert an inhibitory effect on cough by suppressing the expression of TRPA1, CGRP, and SP in lung tissues, thereby identifying the target of the drug.

Direct conversion of Greenberger-Horne-Zeilinger state to Knill-Laflamme-Milburn state in decoherence-free subspace.

Several schemes are proposed to realize the conversion of photonic polarized-entangled Greenberger-Horne-Zeilinger state to Knill-Laflamme-Milburn state in decoherence-free subspace (DFS) via weak cross-Kerr nonlinearity and X-quadrature homodyne measurement with high fidelity. DFS is introduced to decrease the decoherence effect caused by the coupling between the system and the environment. Optimizations to improve the success rate and utilization of residual states are further investigated. This study indicates important applications for quantum information processing in the future.

TGF-ß isoforms inhibit hepatitis C virus propagation in transforming growth factor beta/SMAD protein signalling pathway dependent and independent manners.

Transforming growth factor beta (TGF-ß) plays an important role in the viral liver disease progression via controlling viral propagation and mediating inflammation-associated responses. However, the antiviral activities and mechanisms of TGF-ß isoforms, including TGF-ß1, TGF-ß2 and TGF-ß3, remain unclear. Here, we demonstrated that all of the three TGF-ß isoforms were increased in Huh7.5 cells infected by hepatitis C virus (HCV), but in turn, the elevated TGF-ß isoforms could inhibit HCV propagation with different potency in infectious HCV cell culture system. TGF-ß isoforms suppressed HCV propagation through interrupting several different stages in the whole HCV life cycle, including virus entry and intracellular replication, in TGF-ß/SMAD signalling pathway-dependent and TGF-ß/SMAD signalling pathway-independent manners. TGF-ß isoforms showed additional anti-HCV activities when combined with each other. However, the elevated TGF-ß1 and TGF-ß2, not TGF-ß3, could also induce liver fibrosis with a high expression of type I collagen alpha-1 and α-smooth muscle actin in LX-2 cells. Our results showed a new insight into TGF-ß isoforms in the HCV-related liver disease progression.

Salvianolic acid A prevented cerebrovascular endothelial injury caused by acute ischemic stroke through inhibiting the Src signaling pathway.

Stroke is an acute cerebrovascular disease caused by ruptured or blocked blood vessels. For the prevention of ischemic stroke, the coagulation state of blood and cerebrovascular protection should be considered. Our previous study has shown that salvianolic acid A (SAA), which is a water-soluble component from the root of Salvia Miltiorrhiza Bge, prevents thrombosis with a mild inhibitory effect on platelet aggregation. In this study we investigated the preventive effects of SAA on cerebrovascular endothelial injury caused by ischemia in vivo and oxygen-glucose deprivation (OGD) in vitro, and explored the underlying mechanisms. An autologous thrombus stroke model was established in SD rats by electrocoagulation. SAA (10 mg/kg) was orally administered twice a day for 5 days before the operation. The rats were sacrificed at 24 h after the operation. We showed that pretreatment with SAA significantly improved the neurological deficits, intracerebral hemorrhage, BBB disruption, and vascular endothelial dysfunction as compared with model group. In human brain microvascular endothelial cells (HBMECs), pretreatment with SAA (10 µM) significantly inhibited OGD-induced cell viability reduction and degradation of tight junction proteins (ZO-1, occludin, claudin-5). Furthermore, we found that SAA inhibited the upregulation of Src signaling pathway in vivo and vitro and reversed the increased expression of matrix metalloproteinases (MMPs) after ischemic stroke. In conclusion, our results suggest that SAA protects cerebrovascular endothelial cells against ischemia and OGD injury via suppressing Src signaling pathway. These findings show that pretreatment with SAA is a potential therapeutic strategy for the prevention of ischemic stroke.

Pinocembrin attenuates hemorrhagic transformation after delayed t-PA treatment in thromboembolic stroke rats by regulating endogenous metabolites.

Hemorrhagic transformation (HT) is a common serious complication of stroke after thrombolysis treatment, which limits the clinical use of tissue plasminogen activator (t-PA). Since early diagnosis and treatment for HT is important to improve the prognosis of stroke patients, it is urgent to discover the potential biomarkers and therapeutic drugs. Recent evidence shows that pinocembrin, a natural flavonoid compound, exerts anti-cerebral ischemia effect and expands the time window of t-PA. In this study, we investigated the effect of pinocembrin on t-PA-induced HT and the potential biomarkers for HT after t-PA thrombolysis, thereby improving the prognosis of stroke. Electrocoagulation-induced thrombotic focal ischemic rats received intravenous infusion of t-PA (10 mg/kg) 6 h after ischemia. Administration of pinocembrin (10 mg/kg, iv) prior t-PA infusion significantly decreased the infarct volume, ameliorated t-PA-induced HT, and protected blood-brain barrier. Metabolomics analysis revealed that 5 differential metabolites in the cerebral cortex and 16 differential metabolites in serum involved in amino acid metabolism and energy metabolism were significantly changed after t-PA thrombolysis, whereas pinocembrin administration exerted significant intervention effects on these metabolites. Linear regression analysis showed that lactic acid was highly correlated to the occurrence of HT. Further experiments confirmed that t-PA treatment significantly increased the content of lactic acid and the activity of lactate dehydrogenase in the cerebral cortex and serum, and the expression of monocarboxylate transporter 1 (MCT 1) in the cerebral cortex; pinocembrin reversed these changes, which was consistent with the result of metabolomics. These results demonstrate that pinocembrin attenuates HT after t-PA thrombolysis, which may be associated with the regulation of endogenous metabolites. Lactic acid may be a potential biomarker for HT prediction and treatment.

Outcome-based student assessment enhances academic performance in basic medical laboratory course.

Basic medical laboratory courses (BMLCs) play an important role in medical educational courses helping the student acquire three important skills of surgical operating, collaborative learning, and problem solving. The outcome-based student assessment (OBSA) is a learning evaluation method that establishes specific evaluation points based on performance of students in three aspects: surgical operating, collaborative learning, and problem solving in the BMLC curriculum practices. The purpose of the present randomized controlled trial study is to explore the efficiency of OBSA program in BMLCs. The 233 students attending BMLCs were randomly divided into 2 groups, 118 in the OBSA group and 115 in the control group. We conducted multiple-choice examination questions (MCQs) test and two questionnaires with the method of two-sample t test for statistics. The results of MCQs in total eight BMLC blocks showed that the academic performance of the OBSA group was significantly better than that of the control group (P < 0.05). In addition, the average scores of direct observation of procedural skills (DOPS) and mini-experimental evaluation exercise in OBSA group were significantly higher than those in control group (P < 0.05). The majority of the medical students preferred the OBSA and considered OBSA could effectively improve their surgical operating skills (83.9%), collaborative learning skills (92.1%), and problem-solving skills (91.1%). From the above, OBSA is an effective evaluation method for the implementation of the BMLC curriculum.

Holographic display method with a large field of view based on a holographic functional screen.

In this paper, we propose a method to increase the field of view (FOV) in a holographic display. Different from the traditional method, a large-sized computer-generated hologram (CGH) is generated, and a holographic function screen is used in the proposed method. The CGH is formed by superposition of interference fringes. The diffraction boundary angle of the interferogram is set to be equal to the maximum diffraction angle of the reconstructed light. In the holographic reconstruction, three spatial light modulators (SLMs) arranged side by side in a linear configuration are used to load the CGH. The holographic functional screen is used for eliminating the seams between the SLMs and further enlarging the diffraction light. With the proposed method, the reconstructed light after each image point is expanded, so that the FOV can be increased effectively. Experimental results prove the feasibility of the proposed method.

Molecular characterization and differential expression analysis of interleukin 1ß from Ovis aries.

The interleukin-1 family is an important component of the innate immune system and plays an important role in regulating immune responses on the invasion of intracellular parasites in the acquired immune system. Interleukin 1ß (IL-1ß) is one of the members of the IL-1 family that predominantly activates downstream signaling pathways to play immunological functions of stimulating T and B lymphocyte activation and promoting the various syntheses of inflammatory substances in conjunction with other cytokines. Here, a full-length IL-1ß cDNA (OaIL-1ß) of sheep (Ovis aries) was cloned using rapid amplification of cDNA ends (RACE), which consists of 1494 bp and contains a 5'-UTR region with a length of 83 bp, a complete ORF of 801 bp in length, and a 3'-UTR region with a length of 642 bp. Recombinant protein OaIL-1ß was expressed and purified, and the monoclonal antibody against IL-1ß of sheep is prepared. Western blotting results showed that the sheep IL-1ß protein was detected in the heart, liver, lung, kidney, stomach, intestine, muscle, lymph nodes and leukocytes with the highest expression in the muscle and the lowest expression in the lung. Different bacteria treating sheep white blood cells induced differential expression of OaIL-1ß. Compared with the normal sheep, OaIL-1ß in the buffy coat was differentially expressed in the Brucella melitensis-challenged group and the B. suis S2 strain-inoculated group. However, whether IL-1ß may be considered as a molecular biomarker for differing Brucella-infected animals from brucellosis-vaccinated animals or not need to be further studied.

Theoretical Prediction on [5]Radialene Sandwich Complexes (CpM)2(C10H10) (Cp = η5-C5H5; M = Fe, Co, Ni): Geometry, Spin States, and Bonding.

[5]Radialene, the missing link for synthesis of radialene family, has been finally obtained via the preparation and decomplexation of the [5]radialene-bis-Fe(CO)3 complex. The stability of [5]radialene complex benefits from the coordination with Fe(CO)3 by losing free 1,3-butadiene structures to avoid polymerization. In light of the similar coordination ability of half-sandwiches CpM(Cp = η5-C5H5; M = Fe, Co, Ni), there is a great possibility that the sandwiched complexes of [5]radialene with CpM are available. Herein, we present the first theoretical prediction on the geometry, spin states and bonding of (CpM)(C10H10) and (CpM)2(C10H10). For M = Fe, Co, Ni, the ground states of (CpM)(C10H10) and (CpM)2(C10H10) are doublet and triplet, singlet and singlet, and doublet and triplet states, where each Fe, Co, and Ni adopts 17, 18, and 19 electron-configuration, respectively. In particular, (CpFe)2(C10H10) and (CpNi)2(C10H10) have considerable open-shell singlet features. Generally the trans isomers of (CpM)2(C10H10) with two CpM fragments on the opposite sides of the [5]radialene plane are apparently more stable than the cis ones with CpM fragments on the same side. However, for the singlet and triplet isomers of (CpNi)2(C10H10) (both cis and trans isomers), the energy differences are relatively small, indicating that these isomers all have the opportunity to exist. Besides, the easy Diels-Alder (DA) dimerization between the [3]dendralene-like fragments of (CpM)(C10H10) suggests the great difficulty in isolating the (CpM)(C10H10) monomer.

Melanin production by a yeast strain XJ5-1 of Aureobasidium melanogenum isolated from the Taklimakan desert and its role in the yeast survival in stress environments.

The yeast strain XJ5-1 isolated from the Taklimakan desert soil was identified to be a strain of Aureobasdium melanogenum and could produce a large amount of melanin when it was grown in the PDA medium, but its melanin biosynthesis and expression of the PKS gene responsible for the melanin biosynthesis was significantly repressed in the presence of (NH4)2SO4. However, A. melanogenum P5 strain isolated from a mangrove ecosystem grown in both the presence and the absence of (NH4)2SO4 did not produce any melanin. The cell size of A. melanogenum XJ5-1 strain was much higher than that of A. melanogenum P5 strain. The melanized cells of the yeast strain XJ5-1 had higher tolerance to UV radiation, oxidation (200.0 mM H2O2), heat treatment (40 °C), salt shock (200.0 g/L NaCl), desiccation and strong acid hydrolysis (6.0 M HCl) at high temperature (80 °C) than the non-melanized cells of the same yeast strain XJ5-1. At the same time, the melanized cells of the yeast strain XJ5-1 also had higher tolerance to UV radiation, oxidation (200.0 mM H2O2), desiccation and strong acid hydrolysis (6.0 M HCl) at high temperature (80 °C) than A. melanogenum P5 strain, but had similar resistance to heat treatment (40 °C) and salt shock (200.0 g/L NaCl) compared to those of A. melanogenum P5 strain. All the results revealed that many characteristics of A. melanogenum XJ5-1 isolated from the Taklimakan desert soil was different from those of A. melanogenum P5 strain isolated from the mangrove ecosystem.

Characterization of a highly virulent and antimicrobial-resistant Acinetobacter baumannii strain isolated from diseased chicks in China.

Poultry husbandry is a very important aspect of the agricultural economy in China. However, chicks are often susceptible to infectious disease microorganisms, such as bacteria, viruses and parasites, causing large economic losses in recent years. In the present study, we isolated an Acinetobacter baumannii strain, CCGGD201101, from diseased chicks in the Jilin Province of China. Regression analyses of virulence and LD50 tests conducted using healthy chicks confirmed that A. baumannii CCGGD201101, with an LD50 of 1.81 (±0.11) × 10(4) CFU, was more virulent than A. baumannii ATCC17978, with an LD50 of 1.73 (±0.13) × 10(7) CFU. Moreover, TEM examination showed that the pili of A. baumannii CCGGD201101 were different from those of ATCC17978. Antibiotic sensitivity analyses showed that A. baumannii CCGGD201101 was sensitive to rifampicin but resistant to most other antibiotics. These results imply that A. baumannii strain CCGGD201101 had both virulence enhancement and antibiotic resistance characteristics, which are beneficial for A. baumannii survival under adverse conditions and enhance fitness and invasiveness in the host. A. baumannii CCGGD20101, with its high virulence and antimicrobial resistance, may be one of the pathogens causing death of diseased chicks.

Full-Length cDNA Cloning, Molecular Characterization and Differential Expression Analysis of Lysophospholipase I from Ovis aries.

Lysophospholipase I (LYPLA1) is an important protein with multiple functions. In this study, the full-length cDNA of the LYPLA1 gene from Ovis aries (OaLypla1) was cloned using primers and rapid amplification of cDNA ends (RACE) technology. The full-length OaLypla1 was 2457 bp with a 5'-untranslated region (UTR) of 24 bp, a 3'-UTR of 1740 bp with a poly (A) tail, and an open reading frame (ORF) of 693 bp encoding a protein of 230 amino acid residues with a predicted molecular weight of 24,625.78 Da. Phylogenetic analysis showed that the OaLypla1 protein shared a high amino acid identity with LYPLA1 of Bos taurus. The recombinant OaLypla1 protein was expressed and purified, and its phospholipase activity was identified. Monoclonal antibodies (mAb) against OaLypla1 that bound native OaLypla1 were generated. Real-time PCR analysis revealed that OaLypla1 was constitutively expressed in the liver, spleen, lung, kidney, and white blood cells of sheep, with the highest level in the kidney. Additionally, the mRNA levels of OaLypla1 in the buffy coats of sheep challenged with virulent or avirulent Brucella strains were down-regulated compared to untreated sheep. The results suggest that OaLypla1 may have an important physiological role in the host response to bacteria. The function of OaLypla1 in the host response to bacterial infection requires further study in the future.

SMAD4 is a potential prognostic marker in human breast carcinomas.

SMAD4 is a downstream mediator of transforming growth factor beta. While its tumor suppressor function has been investigated as a prognostic biomarker in several human malignancies, its role as a prognostic marker in breast carcinoma is still undefined. We investigated SMAD4 expression in breast carcinoma samples of different histologic grades to evaluate the association between SMAD4 and outcome in breast cancer. We also investigated the role of SMAD4 expression status in MDA-MB-468 breast cancer cells in responding to TGF-ß stimulation. SMAD4 expression was assessed in 53 breast ductal carcinoma samples and in the surrounding normal tissue from 50 of the samples using immunohistochemistry, Western blot, and real-time PCR. TGF-ß-SMAD and non-SMAD signaling was assessed by Western blot in MDA-MB-468 cells with and without SMAD4 restoration. SMAD4 expression was reduced in ductal breast carcinoma as compared to surrounding uninvolved ductal breast epithelia (p < 0.05). SMAD4 expression levels decreased from Grade 1 to Grade 3 ductal breast carcinoma as assessed by immunohistochemistry (p < 0.05). Results were recapitulated by tissue array. In addition, immunohistochemistry results were further confirmed at the protein and mRNA level. We then found that non-SMAD MEK/MAPK signaling was significantly different between SMAD4 expressing MDA-MB-468 cells and SMAD4-null MDA-MB-468 cells. This is the first study indicating that SMAD4 plays a key role in shifting MAPK signaling. Further, we have demonstrated that SMAD4 has a potential role in the development of breast carcinoma and SMAD4 was a potential prognostic marker of breast carcinoma. Our findings further support the role of SMAD4 in breast carcinoma development. In addition, we observed an inverse relationship between SMAD4 levels and breast carcinoma histological grade. Our finding indicated that SMAD4 expression level in breast cancer cells played a role in responding non-SMAD signaling but not the canonic SMAD signaling. Further mechanistic studies are necessary to establish the role of SMAD4 in breast carcinoma prognosis and potential specific targeting.

A magnetic particles-based chemiluminescence enzyme immunoassay for rapid detection of ovalbumin.

Egg allergy is an important public health and safety concern, so quantification and administration of food or vaccines containing ovalbumin (OVA) are urgently needed. This study aimed to establish a rapid and sensitive magnetic particles-chemiluminescence enzyme immunoassay (MPs-CLEIA) for the determination of OVA. The proposed method was developed on the basis of a double antibodies sandwich immunoreaction and luminol-H2O2 chemiluminescence system. The MPs served as both the solid phase and separator, the anti-OVA MPs-coated polyclonal antibodies (pAbs) were used as capturing antibody, and the horseradish peroxidase (HRP)-labeled monoclonal antibody (mAb) was taken as detecting antibody. The parameters of the method were evaluated and optimized. The established MPs-CLEIA method had a linear range from 0.31 to 100ng/ml with a detection limit of 0.24ng/ml. The assays showed low reactivities and less than 5% of intraassay and interassay coefficients of variation (CVs), and the average recoveries were between 92 and 97%. Furthermore, the developed method was applied in real samples analysis successfully, and the correlation coefficient with the commercially available OVA kit was 0.9976. Moreover, it was more rapid and sensitive compared with the other methods for testing OVA.

Simple, specific, sensitive and rapid loop-mediated method for detecting Yersinia enterocolitica.

Yersinia enterocolitica (YE) is a main pathogenic bacterium causing diarrhea and yersiniosis occurs in both developed and developing countries with high incidence. YE in contaminated food is able to survive for a long duration even under cold storage, thereby enhancing the risk of food infection. In this study, a new loop-mediated isothermal amplification (LAMP) method showing the characteristics of simplicity, rapidity, high specificity and sensitivity was established by targeting outL of pathogenic YE. Two inner-primers and outer-primers were designed and LAMP reaction was optimized for Mg2+, betaine, dNTPs and inner primers concentrations, reaction temperature and time. Sensitivity and specificity of the LAMP assay was evaluated using YE genomic DNA and those of 44 different bacteria strains, respectively. Validation of LAMP detection method was by employing meat samples spiked with varying CFU of YE. The optimized LAMP assay was specific, capable of detecting 97 fg of genomic DNA (equivalent to 37 genome copies) of YE (100-fold more sensitive than PCR) and 80 CFU/ml of YE-spiked meat samples based on ethidium bromide stained amplicon bands on agarose gel-electrophoresis and on GelRed fluorescence of the LAMP reaction solution, respectively. This rapid, sensitive and specific LAMP technique should enable application in field inspection of Y. enterocolitica in food.

[Properties of Biochars Prepared from Different Crop Straws and Leaching Behavior of Heavy Metals].

In this study, rice straw, soybean straw, wheat straw, and corn straw were chosen as raw materials, and biochars were prepared through the pyrolysis method at 550℃ under oxygen-limited conditions to investigate the physicochemical properties of biochars derived from the straws, the migration and transformation characteristics of heavy metals (HMs) (Cr, Ni, Cu, As, Cd, and Pb) after pyrolysis, and their leaching behaviors in different leaching solutions. The results showed that the physicochemical properties and elemental composition of the biochars were basically consistent. However, compared with that of biochars derived from other straws, biochar derived from wheat straw had a higher ash content (22.48%) and H/C radio (0.06). Meanwhile, biochar derived from corn straw had a smaller micropore volume (0.006 cm3·g-1) and a correspondingly smaller specific surface area (110.120 m2·g-1), which was consistent with the SEM image. After pyrolysis, the content of HMs (except Cd) increased by 14.04% to 410.81%, especially that of Cu and As. However, the content of Cd in soybean straw and corn straw decreased by 20.49% and 8.20% after pyrolysis, respectively, due to the low boiling point of Cd. Furthermore, most of the HMs (except Cd and Pb) tended to transform from unstable (acid-soluble/exchangeable and reducible forms) to stable forms (oxidizable and residual forms), implying that pyrolysis facilitated the stabilization of the HMs. The HMs in biochar were not leached or were leached in small amounts in ultra-pure water and buffered salt solutions, as opposed to leaching in relatively larger amounts in acetic acid solution and humic acid solution. Cr and Ni showed low leaching capacity in all leaching solutions. Cu showed relatively high leaching capacity in acetic acid solution, with the leaching amount ranging from 2.601 mg·kg-1 to 4.224 mg·kg-1, and As showed a relatively high leaching capacity in humic acid solution, with the leaching amount ranging from 0.074 mg·kg-1to 0.166 mg·kg-1. After pyrolysis, the environmental quality index (PIi) and the Nemerow pollution index (NPI) values of various HMs increased by different degrees. However, the pollution of single HMs remained at a safe level, and the integrated pollution of biochars was at the level of "clean". Due to the significant increase in potential ecological risk factors (Er) of Ni, Cd, and Pb after pyrolysis, the potential ecological risk index (RI) of biochar derived from the rice straw increased slightly. However, the potential ecological risk indexes of biochars derived from other straws significantly decreased after pyrolysis, owing to the stabilization of HMs.