Macrophage migration inhibitory factor (MIF) acetylation protects neurons from ischemic injury.

Ischemia-induced neuronal death leads to serious lifelong neurological deficits in ischemic stroke patients. Histone deacetylase 6 (HDAC6) is a promising target for neuroprotection in many neurological disorders, including ischemic stroke. However, the mechanism by which HDAC6 inhibition protects neurons after ischemic stroke remains unclear. Here, we discovered that genetic ablation or pharmacological inhibition of HDAC6 reduced brain injury after ischemic stroke by increasing macrophage migration inhibitory factor (MIF) acetylation. Mass spectrum analysis and biochemical results revealed that HDAC6 inhibitor or aspirin treatment promoted MIF acetylation on the K78 residue. MIF K78 acetylation suppressed the interaction between MIF and AIF, which impaired MIF translocation to the nucleus in ischemic cortical neurons. Moreover, neuronal DNA fragmentation and neuronal death were impaired in the cortex after ischemia in MIF K78Q mutant mice. Our results indicate that the neuroprotective effect of HDAC6 inhibition and aspirin treatment results from MIF K78 acetylation; thus, MIF K78 acetylation may be a therapeutic target for ischemic stroke and other neurological diseases.

Characterization of a recombinant d-allulose 3-epimerase from Agrobacterium sp. ATCC 31749 and identification of an important interfacial residue.

d-Allulose 3-epimerase (DAEase) catalyzes the epimerization between d-fructose and d-allulose. We had PCR-cloned and overexpressed the gene encoding Agrobacterium sp. ATCC 31749 DAEase (AsDAEase) in Escherichia coli. A high yield of active AsDAEase, 35,300U/L or 1350U/g of wet cells, was acquired with isopropyl ß-d-1-thiogalactopyranoside induction at 20°C for 20h. Although only six residues including residue 234 located in tetrameric interface are different between AsDAEase and A. tumefaciens DAEase (AtDAEase), the specific activity of purified AsDAEase is much larger than that of AtDAEase. The optimal pHs and optimal temperatures of the purified recombinant AsDAEase are 7.5-8.0 and 55-60°C, respectively. The half-life of the enzyme is 267min at 55°C in the presence of 0.1mM Co2+, and the equilibrium ratio between d-allulose and d-fructose is 30:70 at 55°C. Besides characterizing AsDAEase, mutation N234D was constructed to assess its influence on activity. The specific activity of the purified N234D AsDAEase is only 25.5% of wild-type's activity, suggesting residue N234 is an important interfacial residue which substantially affects enzyme activity. The high specific activity and high expression yield of AsDAEase suggest its prospect to be applied in d-allulose production.

Contrast-enhanced ultrasound-guided percutaneous microwave ablation of renal cell carcinoma that is inconspicuous on conventional ultrasound.

PURPOSE: This study was designed to determine the safety, effectiveness and feasibility of contrast-enhanced ultrasound (CEUS)-guided percutaneous microwave ablation (MWA) of renal cell carcinoma (RCC) that is inconspicuous on conventional ultrasound (US). MATERIALS AND METHODS: A total of 32 RCC nodules in 29 patients (23 men and 6 women) were treated with CEUS-guided percutaneous MWA between January 2010 and September 2014. The median maximum diameter of the nodules was 2.4 cm (interquartile range: 1.8-2.9 cm). The US contrast agent was SonoVue, a second-generation contrast agent. CEUS was applied before the needle was inserted into the tumour, and percutaneous MWA was performed under CEUS-guidance. RESULTS: In total 31 tumours were successfully visualised via CEUS using 1-2 (1.0-2.0 mL) contrast agent injections, and percutaneous MWA was performed under CEUS-guidance. The technical success rate of CEUS-guided percutaneous MWA of RCC was 96.9% (31/32). The mean number of sessions of CEUS-guided percutaneous MWA for each tumour was 1.2 ± 0.4. The mean duration of energy application for each tumour was 7.3 ± 2.7 min. All patients were followed up for 3-71 months (median 17 months) to observe the therapeutic effects and complications. The therapeutic effects were assessed at follow-up with computed tomography (CT) or magnetic resonance imaging (MRI) and CEUS. There was no local tumour progression and the technique effectiveness rate was 100% (31/31). The complications rate was 6.5% and the major complications rate was 3.2%. We observed one case of pleural effusion and one case of renal subcapsular haemorrhage after the percutaneous MWA procedures. CONCLUSION: CEUS-guided percutaneous MWA is a safe, efficient and feasible therapy for patients with RCCs inconspicuous on conventional US.

Syntheses and herbicidal activity of new triazolopyrimidine-2-sulfonamides as acetohydroxyacid synthase inhibitor.

The triazolopyrimidine-2-sulfonanilide, discovered from preparing bioisosteres of the sulfonylurea herbicides, is an important class of acetohydroxyacid synthase (AHAS, EC 4.1.3.18) inhibitors. At least over ten triazolopyrimidine sulfonanilides have been commercialized as herbicides for the control of broadleaf weeds and grass with cereal crop selectivity. Herein, a series of triazolopyrimidine-2-sulfonanilides were designed and synthesized with the aim of discovery of new herbicides with higher activity. The assay results of the inhibition activity of the synthesized compounds against Arabidopsis thatiana AHAS indicated that some compounds showed a little higher activity against flumetsulam (FS), the first commercial triazolopyrimidine-2-sulfonanilide-type herbicide. The ki values of two promising compounds 3d and 8h are respectively, 1.61 and 1.29 microM, while that of FS is 1.85 microM. Computational simulation results indicated the ester group of compound 3d formed hydrogen bonds with the surrounding residues Arg'198 and Ser653, which accounts for its 11.5-folds higher AHAS inhibition activity than Y6610. Further green house assay showed that compound 3d has comparable herbicidal activity as FS. Even at the concentration of 37.5g.ai/ha, 3d showed excellent herbicidal activity against Galium aparine, Cerastium arvense, Chenopodium album, Amaranthus retroflexus, and Rmumex acetasa, moderate herbicidal activity against Polygonum humifusum, Cyperus iria, and Eclipta prostrate. The combination of in vitro and in vivo assay indicated that 3d could be regarded as a new potential acetohydroxyacid synthase-inhibiting herbicide candidate for further study.

Synthesis and fungicidal activities of new 1,2,4-triazolo[1,5-a]pyrimidines.

A series of new acetohydrazone-containing 1,2,4-triazolo[1,5-a]pyrimidine derivatives were designed and synthesized for the purpose of searching for novel agrochemicals with higher fungicidal activity. Their in vitro fungicidal activities against Rhizoctonia solani were evaluated, and the most promising compound, 2-[(5,7-dimethyl[1,2,4]triazolo[1,5-a]pyrimidin-2-yl)sulfanyl]-2'-[(2-hydroxyphenyl)methylidene]acetohydrazide (2-17), showed a lower EC(50) value (5.34 microg ml(-1)) than that of commercial carbendazim (EC(50)=7.62 microg ml(-1)). Additionally, compound 2-17 was also found to display broad-spectrum fungicidal activities, and its EC(50) value (4.56 microg ml(-1)) against Botrytis cinereapers was very similar to that of carbendazim. Qualitative structure-activity relationships (QSARs) of the synthesized compounds were also discussed.

Design and synthesis of N-2,6-difluorophenyl-5-methoxyl-1,2,4-triazolo[1,5-a]-pyrimidine-2-sulfonamide as acetohydroxyacid synthase inhibitor.

Triazolopyrimidine-2-sulfonamide belongs to a herbicide group called acetohydroxyacid synthase inhibitors. With the aim to discover new triazolopyrimidine sulfonanilide compounds with high herbicidal activity and faster degradation rate in soil, the methyl group of Flumetsulam (FS) was modified into a methoxy group to produce a new herbicidal compound, N-2,6-difluorophenyl-5-methoxy-1,2,4-triazolo[1,5-a]pyrimidine-2-sulfonamide (experimental code: Y6610). The enzymatic kinetic results indicated that compound Y6610 and FS have k(i) values of 3.31x10(-6) M and 3.60x10(-7) M against Arabidopsis thaliana AHAS, respectively. The 10-fold lower enzyme-inhibiting activity of Y6610 was explained rationally by further computational simulations and binding free energy calculations. In addition, compound Y6610 was found to display the same level in vivo post-emergent herbicidal activity as FS against some broad-leaf weeds and good safety to rice, maize, and wheat at the dosages of 75-300 gai/ha. Further determination of the half-lives in soil revealed that the half-life in soil of Y6610 is 3.9 days shorter than that of FS. The experimental results herein showed that compound Y6610 could be regarded as a new potential acetohydroxyacid synthase-inhibiting herbicide candidate for further study.

Syntheses of diheterocyclic compounds based on 2-thioacetohydrazide-5,7-dimethyl-1,2,4-triazolo[1,5-a]- pyrimidine.

The syntheses of some diheterocyclic compounds from 2-thioacetohydrazide- 5,7-dimethyl-1,2,4-triazolo[1,5-a]pyrimidine (1) are described. Compound 1 can be converted into triazoles, 1,3,4-oxadiazoles, and 1,3,4-thiadiazoles. The structures of the intermediates and the target compounds were confirmed by (1)H-NMR, MS and elemental analyses.