Ghrelin regulates insulin resistance by targeting insulin-like growth factor-1 receptor via miR-455-5p in hepatic cells

Objective: To explore the mechanism by which ghrelin regulates insulin sensitivity through modulation of miR-455-5p in hepatic cells. Methods: HepG2 cells were treated with or without DAG (1 μM). Glucose consumption, intracellular glycogen content, phosphorylation of PI3K and Akt stimulated by insulin, expression of miR-455-5p, as well as IGF-1R protein level were analyzed. In addition, bioinformatic analysis, dual luciferase reporter assay, miR- 455-5p mimic or inhibitor treatment was conducted to investigate the molecular mechanisms. Results: High glucose treatment upregulated miR-455-5p expression but reduced glucose consumption and glycogen content. DAG reversed the effect of high glucose on glucose metabolism, increased protein level of IGF-1R and phosphorylation of PI3K/Akt stimulated by insulin, as well as downregulated miR-455-5p expression. Bioinformatic analysis indicated IGF-1R was the target of miR-455-5p. Dual luciferase reporter assay, as well as transfection with miR-455-5p mimic/inhibitor confirmed that DAG activated IGF-1R/PI3K/Akt signaling via inhibiting miR-455-5p. Conclusion: DAG improves insulin resistance via miR-455-5p- mediated activation of IGF-1R/PI3K/Akt system, suggesting that suppression of miR-455-5p or activation of DAG may be potential targets for T2DM therapy.

Children with Steroid-resistant Nephrotic Syndrome:Long-term Outcomes of Sequential Steroid Therapy

Objective This study aimed to investigate the long-term outcomes in children with steroid-resistant nephrotic syndrome （SRNS）, who received methylprednisolone pulse therapy （MPT）-based sequential steroid therapy. In particular, we aimed to observe whether these patients had a high risk of adverse events. Methods We conducted a retrospective study over a 5-year period. The long-term outcomes for children with SRNS receiving sequential therapy were observed. Results Sixty-three children were diagnosed with SRNS and underwent MPT-based sequential steroid therapy. Thirty-five （55.6%） achieved complete or partial remission, 19 （30.2%） of whom were in remission even after treatment cessation at last review. The mean time to initial remission after MPT was 24.3±13.1 days. Forty-nine children （77.8%） experienced relapses, of whom 31 （49.2%） demonstrated a frequent relapsing course. Adverse effects relevant to MPT were generally mild and infrequent. Five patients （7.9%） complained of vomiting or nausea during MPT infusion; 25 （39.7%） experienced excessive weight gain and developed an obvious Cushingoid appearance; and 26 （41.3%） had poor growth associated with long-term steroid use. Twenty-eight patients （44.4%） failed to respond to MPT, of whom 21 （33.3%） achieved complete or partial remission with immunosuppressive agents. Conclusion MPT-based sequential steroid therapy appears to be a safe and effective method for inducing rapid remission in childhood SRNS. Further clinical studies are needed to comprehensively evaluate this therapy.

The Clinical Efficacy of Low-Dose Tacrolimus Combined with Tripterygium to Treat the Steroid-Resistant Nephrotic Syndrome

Objective: To observe the clinical efficacy and safety of low dose tacrolimus (TAC) combined with tripterygium (TW) in treatment of steroid resistant nephritic syndrome (SRNS). Method: The patients, who were diagnosed with mesangial proliferative glomerulonephritis (MesPGN) and focal segmental glomerulosclerosis (FSGS) by biopsy and failed to respond to a 3-month treatment with prednisone (1 mg/kg·d), were randomly divided into 2 groups (TAC + TW Group and TW Group). Initially TAC + TW group took TAC 0.05mg/(kg·d) 2 h after meal at 12 h interval. The plasma TAC level was examined after 3 days and was kept at 1.5 - 4 ng·ml;meanwhile, TW was given at 60 mg/d before meal. TW group only took TW (60 mg/d). The efficacy, adverse reactions and plasma TAC levels were observed in each group. Results: 1) Totally 20 SRNS patients completed the trial, 11 of TAC + TW Group and 9 of TW Group. There is no statistical difference between the two groups in terms of age, gender, duration since onset of the disease, blood pressure, 24 h UPQ, serum albumin, creatinine, cholesterol, triglyceride, FBG, kidney pathological categories, time of taking prednisone etc.;2) Urine protein started to decrease after 1 month treatment in both of TAC + TW and TW groups. By the 12th month of treatment, TAC + TW group showed 8 cases of complete remission (72.7%), 2 cases of partial remission (18.2%) and 1 case of no improvement (9.1%), while those of TW groups were 2 (22.2%), 4 (44.5%) and 3 (33.3%), respectively;3) With treatment, the TAC + TW Group patients’ plasma protein was significantly higher than that of pretreatment stage and recovered to normal level after 6 month of treatment. However, there was no significant plasma protein increase in TW Group. No obvious changes were observed on serum creatinine level of patients of both the two groups;4) The incidence of adverse reactions was not significantly different between the two groups. Conclusion: TAC + TW reduced proteinuria of SRNS patients, increased clinical remission rate and was tolerant to SRNS patients. We conclude that TAC + TW treatment is an effective way to treat patients with SRNS.

NPHS2 Gene Mutation and Polymorphisms in Indonesian Children with Steroid-Resistant Nephrotic Syndrome

Objective:?Although several NPHS2 gene mutations and polymorphisms were described and?associated with clinical manifestation of steroid-resistant nephrotic syndrome (SRNS),?the?occurrence of these genetic abnormalities or variants appeared?to be influenced by race and ethnic group. We have investigated?probable mutations and variants in NPHS2 gene involved in SRNS and their association with clinical manifestations. Methods: We examined 28 children?with primary SRNS?whovisited?the pediatric nephrology division of 10 teaching hospitals in Indonesia. Molecular genetic studies of the NPHS2 gene were?conducted through screenings?for the exon 1, exon 2, and exon 8. The mutational analysis of NPHS2 was performed by DNA sequencing.?Fisher’s Exact Test was used to determine?the?correlation?between?NPHS2 polymorphisms and clinical manifestations.Results:?Seven?females (25%) and 21 males (75%)?participated in the study.?The mean age of the subjects with 95% CI is: 7.6 (6.1 - 9.0) years while the mean age at onset of disease with 95% CI is: 5.4 (3.9 - 7.0) years. Sixteen patients (57.14%) were younger than 6 years at the onset of disease. Seventeen (60.7%) subjects had normal eGFR, while 11 (39.3%) had chronic renal insufficiency. The mean eGFR of the subjects with 95% CI is: 111.4 (87.7 - 135.1) ml/min/1.73 m2. The mean systolic blood pressure with 95% CI is: 117.0 (108.9 - 125.1) mmHg and the mean diastolic blood pressure with 95% CI is: 77.0 (70.3 - 83.7) mmHg.?We identified 6 NPHS2polymorphisms,?i.e.?g.-52G>T, c.101A>G, g.-117C>T, c.288C>T, c.954C>T, and c.1038A>G and no mutation?was found. There was?no correlation?between?NPHS2 polymorphisms and clinical manifestations (p > 0.05). Conclusion: The?results demonstrate no mutation of NPHS2 gene, and the 6 NPHS2 gene polymorphisms that were identified have no correlation with the clinical manifestation in Indonesian children with SRNS.

Histopathology Review of Idiopathic Steroid Resistant Nephrotic Syndrome and Outcome in Children in North-West of Iran

Introduction: There is currently little information in the literature on the spectrum of histopathologic patterns in children presenting with idiopathic steroid-resistant nephrotic syndrome (iSRNS) in Iran. We conducted to compare the histopathologic distribution of different subtypes’ glomerular morphologic patterns in iSRNS and the clinical and biochemical parameters at the time of diagnosis and outcome of patients after immunosuppressive therapy. Material and Methods: This cross sectional study was done in two hundred children, aged 1 - 15 years, who were diagnosed for iSRNS and no response to 4 weeks of standard prednisone therapy (60 mg/m2/day) referred to nephropathology Department of Emam Reza hospital between 2005 and 2013. Demographic, clinical, laboratory, and histopathological data were retrieved from files and original renal biopsy reports. We discussed histopathologic diagnosis and outcome of iSRNS after initial therapy in patients separately. This study investigated prognostic effects of histopathologic pattern on outcome of iSRNS. Results: The study included 200 children with iSRNS: 141 (70.5%) were males and 59 (29.5%) females, with male-to-female ratio of 2.4:1. The mean age was 7.23 ± 4.37 years (range: 1 - 15 years). Upon pathologic investigation of iSRNS cases, focal segmental glomerulosclerosis (NOS subtype) was the first, with a highest prevalence at a rate of 102/200 (51%) and MGN was the last, at a rate of 7/200 (3.5%). Children with iSRNS secondary to MCD are more likely to achieve remission and have better long term prognostic value (P 0.00). Focal segmental glomerulosclerosis (FSGS) (Tip and Collapse subtypes) is more likely to have worse outcome in response to immunosuppressive therapy (P 0.04). Conclusions: This study defines the true spectrum of clinicohistopathology patterns underlying iSRNS in children in Northwest of Iran. Also this study shows that the response to cyclosporine can be correlated with the underlying histopathology patterns which have been earned by adequate renal biopsy.

Identification and Evaluation of Insect and Disease Resistance in Transgenic Cry1Ab13-1 and NPR1 Maize

PCR detection,quantitative real-time PCR(q-RTPCR),outdoor insect resistance,and disease resistance identification were carried out for the detection of genetic stability and disease resistance through generations(T2,T3,and T4)in transgenic maize germplasms(S3002 and 349)containing the bivalent genes(insect resistance gene Cry1Ab13-1 and disease resistance gene NPR1)and their corresponding wild type.Results indicated that the target genes Cry1Ab13-1 and NPR1 were successfully transferred into both germplasms through tested generations;q-PCR confirmed the expression of Cry1Ab13-1 and NPR1 genes in roots,stems,and leaves of tested maize plants.In addition,S3002 and 349 bivalent gene-transformed lines exhibited resistance to large leaf spots and corn borer in the field evaluation compared to the wild type.Our study confirmed that Cry1Ab13-1 and NPR1 bivalent genes enhanced the resistance against maize borer and large leaf spot disease and can stably inherit.These findings could be exploited for improving other cultivated maize varieties.

基于Wnt/β-catenin/TRPC6/CaN通路探讨淫羊藿苷对激素抵抗性肾病综合征大鼠泼尼松抵抗的作用机制

目的观察淫羊藿苷对激素抵抗性肾病综合征(SRNS)大鼠泼尼松抵抗的改善作用,及对Wnt/β-catenin/TRPC6/CaN通路表达的影响。方法将50只SD大鼠分为空白组、模型组、泼尼松组(6.3 mg/kg)、淫羊藿苷组(50 mg/kg)和联合组,每组10只。采用2次尾静脉注射阿霉素建立SRNS大鼠模型,分别予相应方式干预6周。观察大鼠一般状态,检测24 h尿蛋白定量(24 h-UTP)、尿17-羟皮质类固醇(17-OHCS)及血清生化指标,Masson染色观察肾组织病理形态及超微结构,RT-PCR、Westernblot检测肾组织Wnt/β-catenin/TRPC6/CaN通路相关基因及蛋白表达。结果与空白组比较,模型组大鼠体质量、进食量、饮水量均明显减少,24 h-UTP增加、尿17-OHCS含量减少(P<0.01),血肌酐(SCr)、血尿素氮(BUN)、血清总胆固醇(TC)、三酰甘油(TG)含量升高(P<0.01),血清总蛋白(TP)、白蛋白(ALB)含量降低(P<0.05,P<0.01);肾小球增大,基底膜增厚,球囊壁增厚伴纤维化,足细胞空泡变性,有大量胶原纤维沉积,胶原容积分数(CVF)增加(P<0.01);Wnt、β-catenin、TRPC6、CaM、CaN、NFAT1 mRNA和蛋白表达均明显升高(P<0.01),F-actin、MYH9mRNA和蛋白表达明显降低(P<0.01)。与模型组比较,联合组大鼠体质量、饮水量明显增加,24 h-UTP降低、尿17-OHCS含量增加(P<0.01),SCr、BUN、TG含量降低(P<0.01);肾组织纤维化程度减轻,CVF减少(P<0.01),足突融合现象明显好转,足细胞结构趋于正常;肾组织Wnt、β-catenin、TRPC6、CaM、CaN、NFAT1 mRNA和蛋白表达明显降低,F-actin、MYH9 mRNA和蛋白表达明显升高(P<0.01,P<0.05)。结论淫羊藿苷可能通过抑制Wnt/β-catenin/TRPC6/CaN通路,上调骨架蛋白F-actin、MYH9基因和蛋白表达,进而保护足细胞结构、减缓足细胞损伤,改善SRNS大鼠泼尼松抵抗。

Effect of Nano - Titanium Dioxide with Different Antibiotics against Methicillin-Resistant Staphylococcus Aureus

The different investigation has been carried out on the biological activities of titanium dioxide nanoparticle but the effect of this nano product on the antibacterial activity of different antibiotics has not been yet demonstrated. In this study the nano size TiO2 is synthesized using citric acid and alpha dextrose and the enhancement effect of TiO2 nanoparticle on the antibacterial activity of different antibiotics was evaluated against Methicillin-resistant Staphylococcus aureus (MRSA). During the present study, different concentrations of nano-scale TiO2 were tested to find out the best concentration that can have the most effective antibacterial property against the MRSA culture. Disk diffusion method was used to determine the antibacterial activity of these antibiotics in the absence and presence of sub inhibitory concentration of TiO2 nano particle. A clinical isolate of MRSA, isolated from Intensive Care Unit (ICU) was used as test strain. In the presence of sub-inhibitory concentration of TiO2 nanoparticle (20 μg/disc) the antibacterial activities of all antibiotics have been increased against test strain with minimum 2 mm to maximum 10mm. The highest increase in inhibitory zone for MRSA was observed against pencillin G and amikacin (each 10 mm). Conversely, in case of nalidixic acid, TiO2 nanoparticle showed a Synergic effect on the antibacterial activity of this antibiotic against test strain. These results signify that the TiO2 nanoparticle potentate the antimicrobial action of beta lactums, cephalosporins, aminoglycosides, glycopeptides, macrolids and lincosamides, tetracycline a possible utilization of nano compound in combination effect against MRSA.

Relationship Between Serum microRNA-372-3p and Glucose Transporter 4 Levels and Insulin Resistance in Gestational Diabetes Mellitus

Objective:To observe the changes in insulin resistance in patients with gestational diabetes mellitus(GDM)based on the detection of serum microRNA-372-3p and glucose transporter protein 4(GLUT4)levels.Methods:We conducted a retrospective cohort study of 42 patients who were diagnosed with GDM and hospitalized in our hospital during the period from January 2017 to December 2021 and another 42 patients who had normal pregnancy during the same period by collecting their clinical data.We analyzed their serum microRNA expression profiles and miR-372-3p levels to study the relationship between GDM and insulin resistance.Results:The relative expression of miR-372-3p in the serum of patients in the GDM group was significantly higher than that of patients in the control group,but the GLUT 4 level of the GDM group was significantly lower than that of the control group(P<0.05).Compared with the control group,the GDM group had significantly higher levels of fasting blood glucose(FBG),fasting insulin(FINS),2-hour postprandial blood glucose(2h-BG),total cholesterol(TC),triglyceride(TG),and homeostatic model assessment for insulin resistance(HOMA-IR)index but significantly lower homeostasis model assessment ofβ-cell function(HOMA-β)index(P<0.05).The relative expression of miR-372-3p in serum was independently and positively correlated with HOMA-IR,while the level of GLUT4 was independently and negatively correlated with HOMA-IR(P<0.05).Conclusion:Glycosylated hemoglobin test in the early stages of pregnancy(12–13 weeks of gestation)is important to ensure the health of pregnant women and fetuses.The screening and intervention for elevated glucose in pregnant women act as a guideline for the treatment of GDM.Patients with insulin resistance and related complications such as hyperinsulinemia and hypoglycemia should be given priority.

Association of KRAS Gene and microRNA-124-3p in Sporadic Colorectal Tumours

Aim: To reveal the exonic and 3’UTR sequences of KRAS, TP53, APC, BRAF, PIK3CA genes in sporadic colorectal tumors and to investigate the clinical relevance of 3’UTR variations in miRNA profiles. Methods: In the study, the exonic and 3’UTR sequences of five genes in 12 sporadic colorectal tumors were extracted by next generation sequencing. In tumors with variation in the 3’UTR region, the changes caused by the variation in the miRNA binding profile were detected. The expression profile of these miRNAs in colorectal and other solid tumors compared to normal tissue was determined. Pathway analysis was performed to determine which signaling pathways miRNAs affect. Results: Case-10 in our study was wild type KRAS and received cetuximab treatment and developed drug resistance. In this case, it was concluded that the expression of KRAS increased and tumorigenesis progressed due to miRNAs that do not bind to this region due to variations in the 3’UTR region. Among these miRNAs, hsa-miR-124-3p was found to have decreased expression in colorectal tumors and to be associated with the ECM-receptor interaction pathway. Conclusion: Variations in the 3’UTR regions of genes critical in the process of carsinogenesis are associated with drug resistance and the process of tumorigenesis.

Coating Resistant Refractory Castables YB/T 4193-20091

1 Scope This standard specifies the term, definition, classification, technical requirements, test methods, quality appraisal procedures, packing, marking, transportation, storage, and quality certificate of coating resistant refractory eastables.

苏葶平喘汤对激素抵抗型哮喘小鼠模型AP-1、c-Fos表达的影响

目的探讨苏葶平喘汤对激素抵抗型难治性哮喘小鼠癌蛋白Fos(c-Fos)及血清核转录因子激活蛋白-1(activator protein 1,AP-1)表达的影响,试分析苏葶平喘汤对难治性哮喘的干预机制。方法将50只雌性SPF级BALB/c小鼠随机分为5组,分别为空白组(A)、模型组(B)、苏葶平喘汤组(C)、地塞米松组(D)和苏葶平喘汤+地塞米松组(E),每组10只。除空白组外,剩余4组均将小鼠建立为激素抵抗型哮喘模型。药物干预结束后进行取材,利用酶联免疫吸附测定(ELISA)法、实时荧光定量聚合酶链式反应(Real-time PCR)分别检测小鼠血清AP-1、肺组织c-Fos的表达水平。结果1.ELISA检测结果显示:模型组小鼠较空白组小鼠血清中AP-1的值明显增高(P<0.05),苏葶平喘汤组、地塞米松组及苏葶平喘汤+地塞米松组较空白组的小鼠血清AP-1值均降低(P<0.05),其中以苏葶平喘汤+地塞米松组的降低最为显著(P<0.05)。2.PCR检测结果显示:模型组与其余各组相比小鼠肺组织的c-FosmRNA表达明显升高(P<0.05),苏葶平喘汤组、地塞米松组和苏葶平喘汤+地塞米松组c-FosmRNA表达下降(P<0.05),地塞米松组、苏葶平喘汤组和苏葶平喘汤+地塞米松组小鼠的肺组织c-FosmRNA表达水平则无明显差异。结论苏葶平喘汤治疗激素抵抗型哮喘可通过影响AP-1及c-Fos的表达水平来实现抑制哮喘炎症反应控制激素抵抗型哮喘症状的作用。

Steroid resistance in leukemia

There are several types of leukemia which are characterized by the abnormal growth of cells from the myeloid or lymphoid lineage. Because of their lympholytic actions, glucocorticoids(GCs) are included in many therapeutic regimens for the treatment of various forms of leukemia. Although a significant number of acute lymphoblastic leukemia patients respond well to GC treatment during initial phases; prolonged treatments sometimes results in steroid-resistance. The exact mechanism of this resistance has yet not been completely elucidated, but a correlation between functional GC receptor expression levels and steroidresistance in patients has been found. In recent years, several other mechanisms of action have been reported that could play an important role in the development of such drug resistances in leukemia. Therefore, a better understanding of how leukemic patients develop drug resistance should result in drugs designed appropriately to treat these patients.

Risk of coronary arterial lesions in immunoglobulin resistant Kawasaki disease

Objective: High-dose intravenous immunoglobulin (IVIG) decreases the risk for development of coronary arterial lesions (CAL) in Kawasaki disease (KD) while patients resistant to IVIG have higher risk. This study is aimed to investigate an additional therapy affects the risk for CAL in IVIG resistant KD. Design: The information from 11,510 children with KD was collected by the nationwide survey (2003-2004) in Japan. The secondary therapeutic strategies for IVIG resistant KD were an additional IVIG dose, steroids or both. The incidence of CAL was compared among 4 groups: G1, children responded to initial IVIG;G2, IVIG resistant patients receiving an additional IVIG dose;G3, IVIG resistant patients receiving additional steroids;G4, IVIG resistant patients receiving an additional IVIG dose plus steroids. CAL was assessed at 30th day of illness using ultrasound echocardiography. Results: 2229 patients (19.4%) were resistant to initial IVIG. Incidence of CAL was significantly lower in children responding to initial IVIG than in IVIG resistant patients (1.9% and 11.0%, respectively;odd’s ratio 6.3). The incidences of CAL in an each additional therapy group were as follows: G2: 6.7%, G3: 9.7%, G4: 22.2%. The risk for CAL was significantly higher in G4 as compared with G2 and G3. Giant aneurysmal formation (GA) was more frequently developed in G3 and G4 consisting of the patients receiving steroids (G1: 0.03%, G2: 0.63%, G3: 4.3%, G4: 3.7%). Conclusion: The incidence of CAL was considerably high in IVIG resistant KD and an additional therapy by steroids may increase the risk for GA.

Activity of the Fungicide JS399-19 Against Fusarium Head Blight of Wheat and the Risk of Resistance

This report reviews the characteristics of JS399-19, a novel cyanoacrylate fungicide. JS399-19 strongly inhibits the mycelial growth of the fungal plant pathogens of the genus Fusarium and exhibits great potential in controlling Fusarium head blight （FHB） on wheat and other cereals. The mode of action of JS399-19 is evidently different from that of benzimidazole （for example, carbendazim） and other sort of fungicides, making it a possible replacement for carbendazim in China to manage carbendazim-resistant subpopulations of Fusarium graminearum and F. asiaticum. JS399-t9 has excellent protective and curative activity against these pathogens. Incorrect use of this fungicide, however, is likely to select for resistance. Among JS399-19-resistant mutants of F. asiaticum induced in the laboratory, the resistant level of mutants was high and the phenotype of resistance against JS399-19 was conferred by a major gene by genetic analysis. The fitness of laboratory-induced JS399-19-resistant mutants of F. asiaticum was nearly equal to that of their parents. JS399-19 lacks cross resistance with other sort fungicides. To control FHB with JS399-19 and to delay the development of the fungicide-resistance, farmers should use tank mixtures containing JS399-19 and carbendazim, metconazole, tebuconazole, or prothioconazole.

Severe ulcerative colitis: At what point should we define resistance to steroids?

Corticoesteroids are still the first-line treatment for active ulcerative colitis more than 50 years after the publication of trials assessing their beneficial effect, with about a 50% remission rate in cases of severe disease. The mortality related to severe attacks of ulcerative colitis has decreased dramatically, to less than 1%, in experienced centers, due to the appropriate use of intensive therapeutic measures (intravenous steroids, fluids and electrolytes, artificial nutritional support, antibiotics, etc), along with timely decision-making about second-line medical therapy and early identification of patients requiring colectomy. One of the most difficult decisions in the management of severe ulcerative colitis is knowing for how long corticosteroids should be administered before deciding that a patient is a non-responder. Studies assessing the outcome of acute attacks after steroid initiation have demonstrated that, in steroid-sensitive patients, the response generally occurs early on, in the first days of treatment. Different indexes to predict treatment failure, when applied on the third day of treatment, have demonstrated a high positive predictive value for colectomy. In contrast to this resolute approach, which is the most widely accepted, other authors have suggested that in some patients a completeand prolonged response to steroids may take longer. Either way, physicians taking care of these patients need to recognize that severe ulcerative colitis may be life-threatening, and they need to be careful with excessively prolonged medical treatment and delayed surgery.

Influence of rare earth elements on corrosion resistance of BFe10-1-1 alloys in flowing marine water

The corrosion behavior of BFe10-1-1 alloy with different rare earth （RE） contents in simulated flowing marine water was investigated by X-ray diffractometer and scanning electron microscope （SEM）. It was demonstrated that the corrosion rate of BFel0-1-1 alloy with the same chemical compositions in faster flow velocity of marine water was higher than that in a lower flow velocity of marine water. Fixing the flow velocity, BFe 10-1-1 alloy had the best flushing corrosion resistance when the RE content was 0.04wt.%. The consequence of such good corrosion resistance was attributed to the formation of compact protective film on alloy surface containing RE phase such as CeNis. The RE-contained film combines with other corrosion products firmly, which was difficult to fall off from the alloy surface in the flowing marine water. Additionally, SEM analysis confirmed that pitting mechanism, which would be transformed to spalling mechanism gradually with further increasing RE content, was the prevalent mechanism when the alloy contained 0.04wt.%RE.

Characterization and functional analysis of β-1,3-galactosyltransferase involved in Cry1Ac resistance from Helicoverpa armigera(Hübner)

Carbohydrate chains are the principal antigens by which Bacillus thuringiensis（Bt） identify receptor proteins. The interaction between the antigen and Bt causes a pore in the membrane of midgut epithelial cells of insects. Receptor proteins, such as aminopeptidase N and alkaline phosphatase, are glycoproteins. Cadherin is another cell surface receptor protein which has potential glycosylation sites. Glycosyltransferase is very important for the synthesis and modification of receptor proteins. It can indirectly influence the function of Bt. The 1 950 bp full-length c DNA encoding β-1,3-galactosyltransferase was cloned from the the midgut of Helicoverpa armigera by degenerative PCR combined with RACE techniques（GAL-Harm, Gen Bank accession no.： GQ904195.1） with two potential N-glycosylation sites（^157NNTI^160 and ^272NKTL^275）. Protein sequence alignments revealed that H. armigera β-1,3-galactosyltransferase shared high identity with β-1,3-galactosyltransferase in other insect species. The expression level of the β-1,3-galactosyltransferase gene in Cry1Ac-resistant H. armigera larvae was 9.2-fold higher than that in susceptible strain. The function of β-1,3-galactosyltransferase was investigated using RNAi technique. The result showed Cry1 Ac enhanced the toxicity against the si RNA-treated larvae compared with non-si RNA-treated ones, which indicated β-1,3-galactosyltransferase played an important role for the insecticidal toxicity of Cry1 Ac in H. armigera.

Effect of Fused MgO-ZrO_2 Clinker Addition on Thermal Shock Resistance of MgO-ZrO_2 Unfired Bricks

MgO -ZrO2 unfired bricks with ZrO2 content up to 8% at the interval of 2% were prepared, using fused magnesia （ MgO ： 97% ） and fused MgO - ZrO2 clinker （ ZrO2 ： 14. 33% ） as starting materials and phenolic resin as binder. The effects of ZrO2 content on thermal shock resistance （TSR） and other properties such as cold and hot modulus of rupture have been investigated. Re- sidual cold modulus of rupture ratio after heating at 1 000 ℃ and quenching by air blowing was adopted to characterize TSR. Addition of the MgO -ZrO2 clinker improves TSR, attributing to the microcrack toughening effect by thermal expansion mismatch between different phases. When ZrO2 content goes above 4%. the impro- ving effect tends to be moderate. The introduction of MgO- ZrO2 clinker can also improve the HMOR at 1 500 ℃, while the increased ZrO2 content reduces CMOR of the bricks prefired at 1 600 ℃, due to the thermal expansion mismatch effect. Compromising the overall properties, the optimal ZrO2 content for such magnesia based unfired brick is suggested to be 4%.

Structure of Micro-nano WC-10Co4Cr Coating and Cavitation Erosion Resistance in NaCl Solution

Cavitation erosion （CE） is the predominant cause for the failure of overflow components in fluid machinery. Advanced coatings have provided an effective solution to cavitation erosion due to the rapid development of surface engineering techniques. However, the influence of coating structures on CE resistance has not been sys- tematically studied. To better understand their relationship, micro-nano and conventional WC-10Co4Cr cermet coat- ings are deposited by high velocity oxygen fuel spray- ing（HVOF）, and their microstructures are analyzed by OM, SEM and XRD. Meanwhile, characterizations of mechan- ical and electrochemical properties of the coatings are carried out, as well as the coatings＇ resistance to CE in 3.5 wt % NaC1 solution, and the cavitation mechanisms are explored. Results show that micro-nano WC-10Co4Cr coating possesses dense microstructure, excellent mechanical and electrochemical properties, with very low porosity of 0.26 4-0.07% and extraordinary fracture toughness of 5.58 4-0.51 MPa.m1/2. Moreover, the CE resistance of micro-nano coating is enhanced above 50% than conventional coating at the steady CE period in 3.5 wt % NaC1 solution. The superior CE resistance of micro- nano WC-10Co4Cr coating may originate from the unique micro-nano structure and properties, which can effectively obstruct the formation and propagation of CE crack. Thus,a new method is proposed to enhance the CE resistance of WC-10Co4Cr coating by manipulating the microstructure.