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1.
Territrem C, a new tremorgenic mycotoxin (C28H32O9; molecular weight, 512.20) was isolated from the chloroform extract of rice cultures of Aspergillus terreus 23-1, which also produces territrems A and B. Isolation, acute toxicity, and some physicochemical properties of territrem C are discussed in this paper. The spectral and chemical evidence indicated that the structural difference between territrem C and territrem B (C29H34O9) was in their phenyl moieties: a 4-hydroxy-3,5-dimethoxy phenyl group in territrem C and a 3,4,5-trimethoxy phenyl group in territrem B. It was also demonstrated that territrem B was obtained by methylation of territrem C with dimethyl sulfate.  相似文献   

2.
Territrem C, a new tremorgenic mycotoxin (C28H32O9; molecular weight, 512.20) was isolated from the chloroform extract of rice cultures of Aspergillus terreus 23-1, which also produces territrems A and B. Isolation, acute toxicity, and some physicochemical properties of territrem C are discussed in this paper. The spectral and chemical evidence indicated that the structural difference between territrem C and territrem B (C29H34O9) was in their phenyl moieties: a 4-hydroxy-3,5-dimethoxy phenyl group in territrem C and a 3,4,5-trimethoxy phenyl group in territrem B. It was also demonstrated that territrem B was obtained by methylation of territrem C with dimethyl sulfate.  相似文献   

3.
The chemical reaction of cleavaging territrem B to give 3,4,5-trimethoxy benzoic acid by alkaline hydrogen peroxide was investigated. The method was applied for confirmation of the chemical structure of the aromatic moiety of territrem A, A’, B, and B’. The physicochemical properties of the aromatic cleavage product of territrem Aindicated the structure as 3,4-methylendioxy, 5-methoxy benzoic acid (or 4-methoxy, 6-carboxy, 1, 3-benzodioxole). The experiment also gave the evidences that territrem A and A’, on the other hand territrem B and B’ have the identical aromatic moieties on their structures.  相似文献   

4.
We have isolated a metabolite of territrem, designated territrem B', from the chloroform extract of a rice culture of Aspergillus terreus 23-1 by using the same isolation procedure as that for territrems A, B, and C. The present isolation procedure gave about 10 mg of territrem B' from 4 kg of rice culture per batch. Analysis of the high-resolution mass spectrum showed that the molecular composition of territrem B' is C29H34O10 (found, 542.2167; required, 542.200). Some results of physicochemical and acute tests are presented in this paper. Single-crystal X-ray diffractometry of territrem B' indicated that the three-dimensional structure of territrem B' has not changed significantly from that of territrem B except for the insertion of one oxygen atom into territrem B to make an additional pyron ring in the E ring. The tremorgenic activity of territrem B' is greatly reduced as tested by intraperitoneal injection in mice.  相似文献   

5.
Different radioactive precursors were added to 8-day potato-dextrose liquid cultures of Aspergillus terreus 23-1. Territrems were isolated from chloroform extracts of the cultures at day 14 and purified by thin-layer chromatography and high-pressure liquid chromatography. The territrem B obtained was treated with alkaline hydrogen peroxide, and 3, 4, 5-trimethoxy benzoic acid was isolated from an ethyl acetate extract of the reaction mixture and purified by thin-layer chromatography and high-pressure liquid chromatography. By comparison of the specific radioactivities of territrem B and its cleaved aromatic product (disintegrations per minute per micromole of compound), it was demonstrated that the radioactivity of territrem B was located mainly on its aromatic moiety when [U-C]shikimate, l-[methyl-C]methionine, and l-[methyl-H]methionine were precursors; however, the radioactivity of territrem B was located mainly on its nonaromatic moiety when [2-C]mevalonate was the precursor. Mevinolin, a specific inhibitor of beta-hydroxyl beta-methyl glutaryl coenzyme A reductase, was shown to inhibit production of territrems by A. terreus 23-1. When [U-C]acetate was used as a precursor, mevinolin inhibited the incorporation of radioactive carbon into territrem but mevinolin did not inhibit incorporation of radioactive carbon from [2-C]mevalonate into territrem.  相似文献   

6.
Peng FC  Cheng JS 《Mycopathologia》1997,137(2):125-128
4β-Methoxymethyl-4β-demethyl territrem B [5] was synthesized from 4β-hydroxymethyl-β-demethyl territrem B [4] by treatment with dimethyl sulfate in methanolic NaOH. The structure of 5 was elucidated by uv, nmr and mass spectra. The IC50 of 5 on acetylcholinesterase (AChE) was 6.30 × 10-5 M, which indicated 0.4% of the anti-AChE activity of territrem B [2]. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

7.
Territrems, tremorgenic mycotoxins of Aspergillus terreus.   总被引:3,自引:0,他引:3  
The tremorgenic mycotoxins isolated from Aspergillus terreus were given the trivial names territrem A and B instead of their previous designations of C1 and C2 respectively. High-resolution mass spectral data suggested the molecular formula of territrem A to be C28H30O9 and that of territrem B,C29H34O9. They were partially characterized by ultraviolet, infrared, proton magnetic resonance, and mass spectroscopy. The spectroscopic evidence indicated that their chemical structures were very similar. The procedures of purification were also revised for the complete separation of these two chemically related compounds.  相似文献   

8.
Territrems, tremorgenic mycotoxins of Aspergillus terreus.   总被引:4,自引:3,他引:1       下载免费PDF全文
The tremorgenic mycotoxins isolated from Aspergillus terreus were given the trivial names territrem A and B instead of their previous designations of C1 and C2 respectively. High-resolution mass spectral data suggested the molecular formula of territrem A to be C28H30O9 and that of territrem B,C29H34O9. They were partially characterized by ultraviolet, infrared, proton magnetic resonance, and mass spectroscopy. The spectroscopic evidence indicated that their chemical structures were very similar. The procedures of purification were also revised for the complete separation of these two chemically related compounds.  相似文献   

9.
A. terreus isolates isolated from some bakery products, corn and rice were found to be able to produce territrems. 90% of theA. terreus isolated from bakery products were able to produce territrem A, with a mean of 0.09 ppm, while 80% ofA. terreus isolates produce territrem B with a mean of 0.24 ppm. On the other hand 31.8% of the isolates ofA. terreus from corn were able to produce territrem A with a mean of 0.44 ppm. ConcerningA. terreus isolates from rice, 66.7% were found to produce territrem A, with a mean of 5.28 ppm, and 77.8% of the isolates produced territrem B with a mean of 1.79 ppm.  相似文献   

10.
Fatty acid profiles of purified elementary bodies of Chlamydia trachomatis (CT) serotypes D, G and L3 were investigated by gas liquid chromatography (GLC) utilizing three fused silica capillary columns of different polarities. CT serotype C and C. psittaci (CP) strain DD34 were investigated using one column only due to the lack of adequate quantities of purified material. Significantly similar fatty acid profiles were observed in the serotypes examined. However, based on the percentage ratio of 13-methyl tetradecanoate (i-15:0) to 12-methyl tetradecanoate (a-15:0), serotypes D and L3, with ratios of 0.18 and 0.19, respectively, could be differentiated from serotypes C and G with ratios of 1.3 and 1.5, respectively. CP demonstrated a ratio of 0.4, thus differentiating it from the CT serotypes examined. Fatty acids i-15:0 and a-15:0 were absent in uninfected McCoy cells. Results were significantly comparable in all three capillary columns. This study suggests that GLC could be used for identification and differentiation of Chlamydia serotypes.This paper was presented, in part, at the 55th Conjoint Meeting on Infectious Diseases (CAC-MID) on November 24, 1987, Ottawa, Canada.  相似文献   

11.
Territrems A and B, tremorgenic mycotoxins in the rice culture of Aspergillus terreus, were extracted with hot chloroform. The toxins were cleaned on a silica gel column by direct adsorption-concentration of the extracts followed by desorption with chloroform-acetone (9:1, vol/vol). Crude toxin mixtures were separated by silica gel column chromatography and eluted with benzene-ethyl acetate (65:35, vol/vol). The method gave 112 mg of territrem A, 379 mg of territrem B, and 80 mg of their mixture from 4 kg of rice per batch. The criteria of extraction, cleanup, and separation are provided.  相似文献   

12.
TRB3 is a member of TRB protein family characterized by containing a variant kinase domain without enzymatic activity. Interacting with Ser/Thr protein kinases Akt, TRB3 impairs Akt activation induced by growth factors and insulin. In this study we have examined the potential role of TRB3 in muscle differentiation. Our data indicated that the expression of TRB3 is downregulated during C2C12 cells undergoing muscle differentiation and that overexpression of TRB3 inhibits Akt activation during differentiation. Correspondingly, overexpression of TRB3 inhibits, while knockdown TRB3 enhances C2C12 differentiation. Thus, our studies indicated that TRB3 plays a critical role in muscle differentiation.  相似文献   

13.
The purpose of the research was to prepare and evaluate a topical nanolipidgel (NLH) of terbinafine hydrochloride (TRB), an antimycotic agent, for enhanced skin deposition and improved antifungal activity. Topical solid lipid nanoparticles (SLN) based nanolipidgel was formulated and evaluated. TRB-loaded SLNs were formulated by high-pressure homogenization technique. The stable TRB SLN dispersion was incorporated into a gel using 1% Carbopol 980 NF. Rheological evaluation and texture analysis of the TRB NLH was carried out. Skin permeation, skin deposition, antifungal activity, and occlusivity studies of the nanolipidgel formulation were carried out. The safety of the TRB NLH gel was evaluated using acute skin irritation test on New Zealand White rabbits. The SLN dispersion containing 10% of glyceryl monostearate, 3% of Tween 80, and 1% Plurol Oleique was the most stable. The optimized TRB SLN had a particle size and zeta potential value of 148.6 ± 0.305 nm and −20.4 ± 1.2 mV, respectively. TRB NLH had excellent rheological and texture properties to facilitate its topical application. TRB NLH showed increased skin deposition of the drug over plain (3-fold) and marketed TRB formulation (2-fold). TRB NLH had significantly enhanced antifungal activity against Candida albicans. TRB NLH showed efficient occlusivity and was non-irritant to the rabbit skin with no signs of erythema or edema. Solid lipid nanoparticles-based topical nanolipidgel of terbinafine can be an efficient, industrially scalable, and cost-effective alternative to the existing conventional formulations.KEY WORDS: in vitro antifungal activity, rheological analysis of gel, solid lipid nanoparticles, terbinafine, texture analysis of gel  相似文献   

14.
Territrem B (TRB) is a fungal metabolite isolated from Aspergillus terreus shown previously to be a potent and irreversible inhibitor of acetylcholinesterase (AChE). In the present study, a number of binding and inhibition assays were carried out to further characterize the inhibitory effect of TRB. The results indicate that the binding of TRB (a) is much more selective than a well characterized selective inhibitor of AChE, BW284C51, (b) adopts a one-to-one stoichiometry with the enzyme, (c) cannot be undone by an AChE-regenerating oxime agent, which contrasts the ability of 8 M urea to release AChE-bound TRB, (d) is enhanced by high concentration NaCl but prevented, unless preincubated, by Triton X-100, and (e) exhibits quasi-first order kinetics with an overall inhibition constant of 0.01 nM(-1) min(-1). Together these results suggest a very different irreversible binding (a noncovalent type) from that of the covalent type, which involves typical irreversible AChE inhibitors such as diisopropylfluorophosphate and neostigmine. According to the prediction of a molecular modeling study, the distinct AChE inhibitory characteristics of TRB may arise from the inhibitor being noncovalently trapped within a unique active-site gorge structure of the enzyme. It was predicted that an optimal TRB. AChE binding would position a narrowing connection of the TRB structure at a constricted area near the entrance of the gorge, thereby providing a structural basis for the observed irreversible binding.  相似文献   

15.
摘要 目的:探讨TRB3基因敲除对糖尿病小鼠中骨骼肌萎缩和纤维化的影响。方法:选择30只TRB3敲除(TRB3-/-)小鼠和30只C57/BL6J小鼠,随机分为4组,包括TRB3基因敲除糖尿病模型组(A组)、TRB3基因敲除正常对照组(B组)、普通对照组(C组)和糖尿病模型组(D组)。正常对照组小鼠喂养标准大鼠饲料,糖尿病模型小鼠使用腹腔注射小剂量链脲佐菌素的方法建立糖尿病小鼠模型。进行前肢握力测试、悬栅试验、肌肉功能试验,同时测定骨微结构各指标水平、抗I型胶原蛋白和抗III型胶原蛋白水平、萎缩基因MuRF1和Atrogin-1水平。结果:A组、B组、D组小鼠前肢握力显著低于C组,其中D组小鼠前肢握力最低(P<0.05);A组、B组、D组小鼠悬栅试验倒挂时间显著低于C组,其中D组小鼠悬栅试验倒挂时间最短(P<0.05);A组、B组、D组小鼠肌肉功能CSA值显著低于C组,其中D组小鼠肌肉功能CSA值最低(P<0.05);A组、B组、D组小鼠骨微结构指标BMD、BV/TV、Tb.N、Tb.Th值显著小于C组,其中D组数值最低(P<0.05);而Tb.Sp和SMI值显著大于C组,其中D组数值最高(P<0.05);A组、B组、D组小鼠抗I型胶原蛋白和抗III型胶原蛋白水平显著高于C组,其中D组抗I型胶原蛋白和抗III型胶原蛋白水平最高(P<0.05);A组、B组、D组小鼠萎缩基因MuRF1和Atrogin-1水平显著高于C组,其中D组萎缩基因MuRF1和Atrogin-1水平最高(P<0.05)。结论:TRB3基因敲除可显著减轻糖尿病小鼠中骨骼肌萎缩和纤维化,增加骨强度。  相似文献   

16.
17.
The expression of TRB3 (tribbles 3), an apoptosis regulated gene, increases during endoplasmic reticulum (ER) stress. How mechanical stress affects the regulation of TRB3 in cardiomyocytes during apoptosis is not fully understood. An in vivo model of aorta-caval shunt in adult rats demonstrated the increased TRB3 protein expression in the myocardium. The tumor necrosis factor-alpha (TNF-α) antagonist etanercept reversed the TRB3 protein expression and cardiomyocyte apoptosis induced by AV shunt. An in vitro model of cyclic stretch in neonatal rats was also used to investigate TRB3 expression. We hypothesized that cardiomyocyte apoptosis induced by cyclic stretch is TRB3 dependent. Neonatal rat cardiomyocytes grown on a flexible membrane base were stretched by vacuum to 20% of maximum elongation, at 60 cycles/min. Cyclic stretch significantly increased TRB3 protein and mRNA expression. Addition of c-jun N-terminal kinase (JNK) inhibitor SP600125, TNF-α antibody and etanercept 30 min before stretch reversed the induction of TRB3 protein induced by stretch. Cyclic stretch induced the DNA-binding activity of growth arrest and DNA damaged inducible gene-153 (GADD153) by electrophoretic mobility shift assay. SP600125, JNK siRNA, TNF-α antibody and etanercept abolished the binding activity induced by stretch. TRB3 promoter activity was enhanced by stretch and TRB3-mut plasmid, SP600125, TNF-α antibody and etanercept attenuated TRB3 promoter activity induced by stretch. Exogenous administration of TNF-α recombinant protein to the non-stretched cardiomyocytes increased TRB3 protein expression similar to that seen after stretch. Cyclic stretch induced cardiomyocyte apoptosis is inhibited by TRB3 siRNA and etanercept. The stretch-induced TRB3 is mediated by TNF-α、JNK and GADD153 pathway. These results indicate that TRB3 plays an important role in stretch-induced cardiomyocyte apoptosis.  相似文献   

18.
The European Neolithization process started around 12 000 years ago in the Near East. The introduction of agriculture spread north and west throughout Europe and a key question has been if this was brought about by migrating individuals, by an exchange of ideas or a by a mixture of these. The earliest farming evidence in Scandinavia is found within the Funnel Beaker Culture complex (Trichterbecherkultur, TRB) which represents the northernmost extension of Neolithic farmers in Europe. The TRB coexisted for almost a millennium with hunter–gatherers of the Pitted Ware Cultural complex (PWC). If migration was a substantial part of the Neolithization, even the northerly TRB community would display a closer genetic affinity to other farmer populations than to hunter–gatherer populations. We deep-sequenced the mitochondrial hypervariable region 1 from seven farmers (six TRB and one Battle Axe complex, BAC) and 13 hunter–gatherers (PWC) and authenticated the sequences using postmortem DNA damage patterns. A comparison with 124 previously published sequences from prehistoric Europe shows that the TRB individuals share a close affinity to Central European farmer populations, and that they are distinct from hunter–gatherer groups, including the geographically close and partially contemporary PWC that show a close affinity to the European Mesolithic hunter–gatherers.  相似文献   

19.
目的: 探讨miR-520a-3p调控宫颈癌细胞因子分泌的分子机制。方法: 通过TargetScanHuman分析miR-520a-3p与NF-κB复合体亚基RELA的匹配情况,然后通过荧光素酶报告系统检测miR-520a-3p是否靶向NF-κB复合体亚基RELA;使用LPS刺激宫颈癌HELA细胞后,将miR-520a-3p mimics与转染试剂混合后滴入HELA细胞中,此为过表达组;将miR-520a-3p inhibitor与转染试剂混合后滴入HELA细胞中,此为敲低组,通过酶联免疫吸附试验检测过表达组和敲低组GCSF, GM-CSF, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12 p40, IL-12 p70, IL-13, IL-17, IFN-γ, MCP-1, MCP-5, RANTES, TNFα的表达水平。每次实验重复3次。结果: miR-520a-3p靶向RELA的3’UTR;LPS激活NF-kB信号通路后,宫颈癌HELA细胞分泌的细胞因子GCSF, GM-CSF, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12 p40, IL-12 p70, IL-13, IL-17, IFN-γ, MCP-1, MCP-5, RANTES, TNFα的蛋白表达水平上升(P<0.05);过表达组中NF-κB复合体亚基RELA的蛋白表达水平下降,宫颈癌HELA细胞分泌的上述细胞因子的蛋白表达水平下降(P<0.05);敲低组中NF-κB复合体亚基RELA的蛋白表达水平上升,宫颈癌HELA细胞分泌的上述细胞因子的蛋白表达水平上升(P<0.05)。结论: miR-520a-3p通过靶向NF-κB信号通路的关键分子RELA抑制宫颈癌HELA细胞的细胞因子分泌。  相似文献   

20.
Tribbles homolog 3 (TRB3) has been accounted for regulation of a few cell processes through interaction with other significant proteins. The molecular mechanisms underlying TRB3 in tumorigenesis in lung adenocarcinoma have not been entirely elucidated. The present study is aimed at determining the function and fundamental mechanisms of TRB3 in lung adenocarcinoma progression. TRB3 was highly expressed in A549 and H1299 cells and lung adenocarcinoma tissues compared with human bronchial epithelial cells (HBEpC) and adjacent normal lung tissues. Hypoxia significantly upregulated the expression of TRB3 protein in A549 and H1299 cells in a time-dependent way. Gene expression profiling interactive analysis data analysis indicated that patients with lung adenocarcinoma with excessive expression of TRB3 mRNA had fundamentally shorter survival time. TRB3 knockdown in A549 cells can inhibit cell proliferation and migration, and promote cell apoptosis. TRB3 knockdown reduced the expression of p-ERK and p-JNK, but did not affect the expression of p-P38 MAPK. TRB3 overexpression enhances the malignant transformation abilities of HBEpC such as cell proliferation, migration and colony formation, which could be reversed by U0126 and SP600125. TRB3 overexpression promotes the phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) but was not affected by U0126 and SP600125. The results of coimmunoprecipitation experiments indicated that TRB3 binds directly to ERK and JNK. This study suggests that TRB3 has a potentially carcinogenic role in lung adenocarcinoma by binding to ERK and JNK and promoting the phosphorylation of ERK and JNK. TRB3 can be a possible therapeutic focus for lung adenocarcinoma.  相似文献   

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