BPB

BPB
  • 文章类型: Journal Article
    细菌性穗枯病(BPB)已成为世界范围内水稻最具破坏性的疾病之一,伯克霍尔德氏菌和葡糖芽孢杆菌是引起BPB的两种主要病原体(1)。这种疾病会导致几种类型的损害,最重要的是谷物斑点,腐烂,和圆锥花序枯萎病,这可能导致75%或更多的产量损失(1,3)。近年来,症状包括鞘腐病,谷物斑点,谷物腐烂,在近交和杂交水稻品种中都观察到了穗枯病。这些症状类似于BPB的症状,并导致依赖于品种的产量损失。(3)也报道了BPB的相同症状。为了确认疾病的原因,21个水稻圆锥花序(哈里丹,从Mymensingh地区的农民田地中收集了具有典型BPB症状的本地品种),孟加拉国在10月中旬的雨季,2021年。由于疫情的严重程度,圆锥花序变成深棕色,并产生了沙菲谷物;该领域近100%的水稻穗被严重感染。为了确定病原体,将来自20种具有典型BPB症状的植物的1g米粒通过将其浸入70%乙醇中几秒钟,然后用次氯酸钠溶液(3%)浸泡1分钟进行表面灭菌。然后用灭菌的蒸馏水冲洗颗粒三次。然后用研钵和研棒研磨表面灭菌的谷粒;在研磨过程中加入5mL无菌蒸馏水。然后将提取的悬浮液(20μL)划线或铺展到选择性培养基(S-PG)(2)上。选择在S-PG培养基上显示紫色的细菌菌落并纯化为候选病原体。对于分子表征,使用针对gyrB基因的物种特异性引物进行PCR,得到479bp,如(4)所述。为了进一步验证,对16SF和16SR的PCR产物进行扩增和测序,部分产生约1400bp(1),并将五个16SF部分序列存入NCBIGenBank(OP108276至OP108280)。使用BLAST分析,16SrDNA和gyrB分别与伯克霍尔德氏菌(KU851248.1,MZ425424.1)和剑兰(AB220893,CP033430)具有近99%的同源性。这些纯化的细菌分离株在King'sB培养基上产生可扩散的浅黄色色素,表明毒素黄素的产生(3)。然后通过将10ml悬浮液108CFU/mL接种到BRRIdhan28的囊和鞘中,确认了候选的五种细菌分离株,如前所述(1)。从斑点水稻籽粒中获得的所有细菌分离物在接种的叶鞘上产生浅棕色病变,并在籽粒上斑点。为了实现科赫的假设,从有症状的穗中重新分离出细菌,并通过分析gyrB和16srDNA基因的序列确认为剑兰芽孢杆菌。一起来看,这些结果证实了剑兰是导致我们收集的稻粒样品中BPB的原因。据我们所知,这是孟加拉国由剑兰引起的BPB的第一份报告,需要进一步研究以开发有效的疾病管理技术,否则大米的生产将受到严重阻碍。
    Bacterial panicle blight (BPB) has become one of the most destructive diseases of rice worldwide and Burkholderia gladioli and B. glumae are two major pathogens causing BPB (1). This disease causes several types of damage, most importantly grain spotting, rot, and panicle blight, which can result in yield losses of 75% or more (1,3). In recent years, symptoms including sheath rot, grain spotting, grain rot, and panicle blight have been observed in both inbred and hybrid rice varieties. These symptoms resemble those of BPB and cause cultivar-dependent yield losses. (3) also reported the same symptoms for BPB. To confirm the cause of the disease, 21 rice panicles (Haridhan, a local variety) with typical BPB symptoms were collected from a farmer\'s field in the region of Mymensingh, Bangladesh during the rainy season in mid-October, 2021. Due to the severity of the outbreak, the panicles became dark brown and produced chaffy grains; nearly 100% of the rice panicles in that field were severely infected. To identify the causal pathogen(s), 1g of rice grains from 20 plants with typical BPB symptoms were surface-sterilized by immersing them in 70% ethanol for a few seconds followed by sodium hypochlorite solution (3%) for 1min. The grains were then rinsed with sterilized distilled water three times. Surface-sterilized grains were then ground with a mortar and pestle; 5mL of sterile distilled water was added during grinding. The extracted suspension (20µL) was then either streaked or spread onto the selective medium (S-PG) (2). Bacterial colonies showing purple color on the S-PG medium were selected and purified as candidate pathogens. For molecular characterization, species specific primers targeting gyrB gene were used to perform PCR and resulted in 479bp as reported by (4). To verify further, the PCR products of 16SF & 16SR were amplified and sequenced partially producing around 1400bp (1) and five 16SF partial sequences were deposited into NCBI GenBank (OP108276 to OP108280). 16S rDNA and gyrB revealed almost 99% homology with Burkholderia gladioli (KU851248.1, MZ425424.1) and B. gladioli (AB220893, CP033430) respectively using BLAST analysis. These purified bacterial isolates produced a diffusible light-yellow pigment on King\'s B medium indicating toxoflavin production (3). The candidate five bacterial isolates were then confirmed by inoculating 10ml suspension 108CFU/mL into the panicles and sheaths of BRRIdhan28 in net house condition as described previously (1). All of the bacterial isolates obtained from the spotted rice grains produced light brown lesions on the inoculated leaf sheath as well as spotting on the grain. To fulfill Koch\'s postulates, the bacteria were re-isolated from the symptomatic panicles and were confirmed as B. gladioli by analyzing the sequences of gyrB and 16s rDNA genes. Taken together, these results confirmed that B. gladioli is responsible for causing BPB in the rice grain samples that we collected. To our knowledge, this is the first report of BPB caused by B. gladioli in Bangladesh and further research is necessary to develop an effective disease management technique, or else the production of rice will be severely hampered.
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  • 文章类型: Journal Article
    计算研究引入了一种整体方法,通过测试反应和萃取的溶剂来寻找更绿色的方法。Lesinurad是一种新型的选择性尿酸重吸收抑制剂,用于治疗慢性痛风。进行了计算计算,以选择用于灵敏可见分光光度法测定lesinurrad的最佳酸性染料。使用基于密度泛函理论方法的高斯03软件与B3LYP/6-31G(d)基集进行计算。所获得的结果表明,基于较高的计算相互作用能,溴酚蓝比其他酸性染料更适合lesinurad。所述方法基于lesinurad与理论上选择的酸性染料溴酚蓝反应形成黄色离子对络合物。吸收光谱显示在418nm处的最大尖锐峰。对影响反应的不同因素进行了优化。在2-12μg/mLlesinurad的浓度范围内证明了比尔定律。所述反应用于分光光度法测定纯形式和药物制剂中的lesinurrad。使用四种不同的工具评估所述方法的绿色度,即国家环境方法指数,分析生态尺度,绿色分析程序指数和新颖的分析绿色度度量。就绿色特征的度量而言,拟议的方法似乎优于报道的HPLC方法。
    Computational studies introduce an integral approach for finding greener methods through testing solvents for reactions and extractions. Lesinurad is a novel selective uric acid reabsorption inhibitor prescribed for the treatment of chronic gout. Computational calculations were achieved to choose the best acid dye used for sensitive visible spectrophotometric determination of lesinurad. The calculations were performed using Gaussian 03 software based on density functional theory method with B3LYP/6-31G(d) basis set. The obtained results revealed that bromophenol blue was preferred for lesinurad than other acid dyes based on the higher calculated interaction energy. The described method was based on the reaction of lesinurad with the theoretically selected acid dye bromophenol blue to form a yellow ion-pair complex. The absorption spectra showed maximum sharp peaks at 418 nm. Different factors affecting the reaction were optimized. Beer\'s law was demonstrated over the concentration range of 2-12 μg/mL lesinurad. The described reaction was utilized for the spectrophotometric determination of lesinurad in pure form and in the pharmaceutical preparation. The greenness of the described method was assessed using four different tools namely, the national environmental method index, the analytical eco-scale, the green analytical procedure index and the novel analytical greenness metric. The proposed method seemed to be superior to the reported HPLC method with respect to the metrics of the greenness characters.
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  • 文章类型: Journal Article
    Early diagnosis of neurodegenerative diseases, especially Alzheimer\'s disease (AD), is essential for implementing the appropriate treatment protocols and controlling disease progression. Early AD diagnosis helps patients achieve the best therapeutic outcomes, lessening irreversible neurodegenerative damage and severe cognitive decline. The measurement of brain waves and structural modifications, including gray/white matter and brain volume, have recently been considered a promising approach for brain biometrics because of the inherent specificity, degree of confidentiality, and reproducibility. Brain printing biometrics (BPB) is thus becoming more commonly considered as tool for early AD detection. This review proposes using BPB as a tool for the detection of AD prior to the appearance of persistent hallmark depositions, including Aβ and tau protein aggregations in different brain regions. It also describes BPB authentication, a method of implementation, as well as potential outcomes.
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  • 文章类型: Journal Article
    人IIA组分泌型磷脂酶A2(hGIIA)促进癌细胞增殖,使其成为令人信服的治疗目标,但在其他炎症中也很重要。因此,一直在寻找合适的hGIIA抑制剂。磷脂酶A2的活化和甘油磷脂底物的催化通常导致脂肪酸如花生四烯酸(AA)和溶血磷脂的释放,然后转化为介体化合物,包括前列腺素,白三烯,和血小板活化因子.然而,hGIIA提供AA的能力并不能完全解释其在炎症中的生物学作用,因为现在已经证明它还通过不依赖催化的机制发挥促炎作用。这种机制可能高度依赖于关键的特定分子相互作用,对此的完整机械描述仍然难以捉摸。本综述还介绍了可能介导这种不依赖催化的机制的蛋白质伴侣的当前候选者。一个关键的发现是,选择性抑制hGIIA的非催化依赖性活性是通过五肽的环化衍生物实现的。FLSYK,来源于hGIIA的一级序列。hGIIA对细胞功能的影响似乎取决于所研究的病理学,所以它的作用机制是复杂的和依赖于上下文的。这篇综述是全面的,涵盖了对hGIIA功能和抑制的许多方面的理解的最新进展,以及它们为疾病治疗的临床应用提供的见解。FLSYK的环状类似物,C2,已知最有效的类似物,现已进入针对晚期前列腺癌的临床试验。
    Human group IIA secretory phospholipase A2 (hGIIA) promotes the proliferation of cancer cells, making it a compelling therapeutic target, but it is also significant in other inflammatory conditions. Consequently, suitable inhibitors of hGIIA have always been sought. The activation of phospholipases A2 and the catalysis of glycerophospholipid substrates generally leads to the release of fatty acids such as arachidonic acid (AA) and lysophospholipid, which are then converted to mediator compounds, including prostaglandins, leukotrienes, and the platelet-activating factor. However, this ability of hGIIA to provide AA is not a complete explanation of its biological role in inflammation, as it has now been shown that it also exerts proinflammatory effects by a catalysis-independent mechanism. This mechanism is likely to be highly dependent on key specific molecular interactions, and the full mechanistic descriptions of this remain elusive. The current candidates for the protein partners that may mediate this catalysis-independent mechanism are also introduced in this review. A key discovery has been that selective inhibition of the catalysis-independent activity of hGIIA is achieved with cyclised derivatives of a pentapeptide, FLSYK, derived from the primary sequence of hGIIA. The effects of hGIIA on cell function appear to vary depending on the pathology studied, and so its mechanism of action is complex and context-dependent. This review is comprehensive and covers the most recent developments in the understanding of the many facets of hGIIA function and inhibition and the insight they provide into their clinical application for disease treatment. A cyclic analogue of FLSYK, c2, the most potent analogue known, has now been taken into clinical trials targeting advanced prostate cancer.
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  • 文章类型: Journal Article
    双酚A(BPA)在消费品中的使用已被类似物BPB广泛取代,BPE,BPF,BPS,和BPAF。最近的研究将这些替代品与BPA类似的不良健康结果联系起来,包括动物和人类研究中内分泌途径的破坏。我们设计了一种新的MS方法,专门为这项研究开发的,为了捕获最相关的双酚A替代品,BPB,BPE,BPF,BPS,人体血液和尿液中的BPAF和4-NP可量化子宫内暴露的潜力。据我们所知,这是首次探索子宫内这些BPA类似物暴露的研究,也是美国首次在母体/胎儿对中检测BPA的研究.该方法在来自接受选择性剖腹产的母亲的30个配对的母体尿液和胎儿脐带血样本上运行。90%的母亲和77%的婴儿对至少一种BP类似物检测呈阳性。83%的母亲BPAF检测呈阳性,60%为BPS,57%为BPB,17%为BPF,7%为BPA。57%的婴儿BPAF检测呈阳性,50%的婴儿BPF检测呈阳性。分别在一份脐带血样本中检测到BPA和BPB。在脐带血中未检测到BPS。在任何胎儿脐带血或母体尿液样品中均未检测到BPE。这些发现证明了某些BP类似物在孕妇及其婴儿出生时的普遍性。
    The use of Bisphenol A (BPA) has widely been replaced in consumer products by analogs BPB, BPE, BPF, BPS, and BPAF. Recent studies have linked these substitutes to similar adverse health outcomes as BPA, including disruption of endocrine pathways in animal and human studies. We designed a novel MS method, developed specifically for this study, to capture the most relevant BPA alternatives, BPB, BPE, BPF, BPS, BPAF and 4-NP in human blood and urine to quantify potential in utero exposures. To our knowledge, this is the first study to explore in utero exposure to these BPA analogs and the first U.S. study to test for BPA in maternal/fetal pairs. The method was run on 30 paired maternal urine and fetal cord blood samples from mothers undergoing elective Caesarean sections. 90% of mothers and 77% of babies tested positive for at least one BP analog. 83% of mothers tested positive for BPAF, 60% for BPS, 57% for BPB, 17% for BPF and 7% for BPA. 57% of babies tested positive for BPAF and 50% for BPF. BPA and BPB were detected in one cord blood sample each. BPS was not detected in cord blood. BPE was not detected in any fetal cord blood or maternal urine samples. These findings demonstrate the pervasiveness of some BP analogs in pregnant women and their babies at birth.
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  • 文章类型: Journal Article
    认知功能障碍综合征(CDS)是老年犬的常见病,这可能类似于痴呆症,如阿尔茨海默病(AD)。在人类中,AD与许多危险因素有关,例如脑葡萄糖代谢降低,二十二碳六烯酸(DHA)缺乏症,慢性氧化应激,慢性炎症。通过针对这些风险因素中的一些,我们开发了两种营养解决方案(中链甘油三酯,MCT和脑保护的混合,BPB)以增强认知功能并减缓衰老引起的认知下降。这些在饲养高级狗和猫的殖民地中得到了积极评价。该临床研究的目的是评估具有MCT和BPB的饮食对具有CDS的客户拥有的狗的影响。参与的兽医诊所根据高级犬行为问卷和犬医疗健康问卷确定,对高级犬进行了CDS迹象筛查。将87只狗随机纳入三个饮食组之一,每组29只狗:对照组,6.5%MCT油+BPB(6.5%MCT饮食),9%MCT油+BPB(9%MCT日粮)。饮食喂养90天,在第30天和第90天重新评估每只狗的CDS征象。在90天研究结束时给予6.5%MCT饮食的狗中,所有6类CDS体征均显著改善(p<0.05)。控制仅在6个类别中的4个类别中有所改善。9%MCT饮食仅在接受该饮食的狗中得到改善。这项狗研究的结果证实了MCT和BPB在管理狗的CDS临床症状方面的益处。结果支持我们的假设,即针对与大脑衰老和AD相关的已知风险因素能够改善狗的CDS症状。这些数据可能有助于开发类似的营养混合物来管理MCI和AD。
    Cognitive dysfunction syndrome (CDS) is a common condition in senior dogs, which may be analogous to dementia such as Alzheimer\'s disease (AD) in people. In humans, AD has been associated with many risk factors such as reduced cerebral glucose metabolism, docosahexaenoic acid (DHA) deficiency, chronic oxidative stress, and chronic inflammation. By targeting some of these risk factors, we have developed two nutritional solutions (medium chain triglyceride, MCT and Brain Protection Blend, BPB) to enhance cognitive function and slow aging-induced cognitive decline. These have been positively evaluated in colony housed senior dogs and cats. The objective of this clinical study was to evaluate the effects of diets with MCTs and the BPB on client-owned dogs with CDS. Participating veterinary clinics screened senior dogs for signs of CDS as determined by a Senior Canine Behavior Questionnaire and a Canine Medical Health Questionnaire. Eighty-seven dogs were randomly enrolled into one of three diet groups with 29 dogs per group: Control, 6.5% MCT oil + BPB (6.5% MCT diet), 9% MCT oil + BPB (9% MCT diet). Diets were fed for a period of 90 days, and each dog\'s CDS signs were re-evaluated at day 30 and day 90. All 6 categories of the CDS signs were significantly improved (p <0.05) in the dogs given the 6.5% MCT diet at the end of the 90-day study. Control only improved in 4 out 6 categories. The 9% MCT diet only improved in dogs that accepted the diet. The results from this dog study confirm the benefits of MCT and BPB in managing clinical signs of CDS in dogs. The results support our hypothesis that targeting known risk factors associated with brain aging and AD is able to improve symptoms of CDS in dogs. These data may facilitate the development of similar nutrient blends to manage MCI and AD.
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  • 文章类型: Journal Article
    我们先前在2011年的研究报告了在20种海洋和淡水鱼中检测到BPA和PFAA。有新的证据表明BPA/PFAA对动物的代谢干扰作用,本研究旨在提供时间趋势分析,以确定20种市售香港鱼类中当前的PFAA和BPA浓度。由于大多数国家都禁止制造和使用BPA,BPA替代品的引入最近已被纳入市场。因此,BPB的浓度,测定BPF和BPS。在本研究中,所有淡水和海水鱼类样品均显示出BPA的定量浓度[>定量限值(LOQ<0.5ng/g)]。在一些海洋中检测到BPF(黄色海蛋白,bigeye,金斑家兔鱼,冷落蓬帕诺,鞋舌鞋底,Bleeker的石斑鱼和橙色斑点石斑鱼)和淡水鱼(mud鱼,鲤鱼,罗非鱼,鲶鱼,普通话鱼,草鱼,灰色鱼和斑点蛇头)。其中两种化合物,BPS和BPB只能在海洋鱼类中识别(蛇头,黄色海蛋白)。在PFAA分析中,PFOA,PFDA,全氟辛烷磺酸,在大多数海洋和淡水鱼中都发现了PFUdA和PFDoA。PFOS和PFOA被证明是鱼类中两种主要的PFAA。根据测得的双酚浓度,BPs(BPA,BPB,BPF,BPS)和PFAA,计算了BP(20.5-31.5ng/kb.w./天)和PFAA(1.17-1.83ng/kb.w./天)的平均每日摄入量,发现低于欧洲规定的可容忍每日摄入量(TDI)。然而,与我们之前2011年的研究相比,本研究显示鱼样中BPA的浓度增加了约10倍.尽管食用鱼类接触BPA和PFAA的危险比预计将保持较低,在人类健康风险评估中,应考虑BPA及其类似物以及PFAA的可能的累加代谢干扰作用。
    Our previous study in 2011 reported the detection of BPA and PFAAs in 20 species of marine and freshwater fishes. With an emerging evidence to suggest the metabolic-disrupting effects of BPA/PFAAs in animals, the present study was aimed to provide a time-trend analysis to determine the current concentrations of PFAAs and BPA in 20 commercially available Hong Kong species of fishes. Since the manufacture and use of BPA is being prohibited in most nations, the introduction of BPA alternatives has recently been incorporated in the markets. Therefore, the concentrations of BPB, BPF and BPS were determined. In the present study, all freshwater and seawater fish samples showed quantified concentrations [>Limit of Quantification (LOQ<0.5ng/g)] of BPA. BPF was detected in some marine (yellow seafin, bigeye, goldspotted rabbitfish, snubnose pompano, tongue sole, Bleeker\'s grouper and orange-spotted grouper) and freshwater fishes (mud carp, crucian carp, tilapia, catfish, mandarin fish, grass carp, grey mullet and spotted snakehead). Two of the compounds, BPS and BPB could only be identified in the marine fishes (snubnose pompano, yellow seafin). In PFAA analysis, PFOA, PFDA, PFOS, PFUdA and PFDoA were found in most of the marine and freshwater fishes. PFOS and PFOA were shown to be the two predominant PFAAs in fishes. On the basis of the measured concentrations of bisphenols, BPs (BPA, BPB, BPF, BPS) and PFAAs, the average daily intake for BPs (20.5-31.5ng/kgb.w./day) and PFAAs (1.17-1.83ng/kgb.w./day) were calculated and found to be lower than values of tolerable daily intake (TDI) established in Europe. However, as compared with our previous study in 2011, the present study revealed an approximate 10-fold increase in the concentrations of BPA in the fish samples. Although the hazard ratio of consuming fishes for BPA and PFAA exposure is expected to remain low, possible additive metabolic-disrupting effect of BPA and its analogues as well PFAAs should be taken into consideration for human health risk assessment.
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  • 文章类型: Journal Article
    This study reports the analysis of nine bisphenols (BPA, BPAF, BPAP, BPB, BPC, BPE, BPF, BPS, and BPZ) and related compounds (4-cumylphenol and dihydroxybenzophenone) in honey and food simulant. After sample preconcentration with Oasis HLB cartridges, analytes were silylated and analyzed by GC-MS. The validated methods with LODs in sub ng g-1 were applied to 36 honey samples from European and non-European countries and food simulant stored in selected corresponding containers. Honey samples contained BPA, BPAF, BPE, BPF, BPS, and BPZ in amounts up to 107, 53.5, 12.8, 31.6, 302, and 28.4 ng g-1, respectively. Under simulating conditions, BPA and BPAF were detected in food simulant up to 42.2 and 19.8 ng mL-1, respectively. In certain cases, the detected bisphenols in honey probably derive from a source other than the final packaging.
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  • 文章类型: Journal Article
    Biosecurity measures are the first line of defense against highly pathogenic avian influenza (HPAI) on farms. It is generally recognized that an individual\'s behavior can be influenced by the knowledge they possess. However, empirical study has not reported an association between poultry producers\' awareness of HPAI symptoms and their actual biosecurity actions. The aim of this study is to classify knowledge items of HPAI by exploratory factor analysis (EFA) and to examine the determinants of different types of knowledge and the effect of different types of knowledge on biosecurity preventive behaviors (BPBs). The survey (n = 297) was conducted using a questionnaire to measure the level of awareness of items related to HPAI and the actual adoption of BPBs among poultry farmers in the Chinese province of Jiangsu. The EFA revealed three main types of knowledge, which were categorized as avian influenza (AI) epidemic characteristics, primary biosecurity preventive knowledge (basic biosecurity preventive knowledge against AI), and essential biosecurity preventive knowledge (crucial biosecurity preventive knowledge against infection of AI). Multivariate regression showed that only poultry farmers\' awareness of essential biosecurity preventive knowledge was positively associated with their actual BPBs. Additionally, educational attainment, number of years of experience raising poultry, farming operation size, and training were associated both with BPB and most of the knowledge factors or knowledge items. Training of existing poultry farmers is probably a feasible scheme; furthermore, the training should focus on the essential biosecurity preventive knowledge. On the other hand, policy initiatives to encourage large-scale poultry farming while discouraging small-scale backyard poultry husbandry would be an effective method of improving the management standards of rural poultry farming.
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  • 文章类型: Journal Article
    γ-Aminobutyric acid (GABA) receptors (GABARs) are an important target for existing insecticides such as fiproles. These insecticides act as noncompetitive antagonists (channel blockers) for insect GABARs by binding to a site within the intrinsic channel of the GABAR. Recently, a novel class of insecticides, 3-benzamido-N-phenylbenzamides (BPBs), was shown to inhibit GABARs by binding to a site distinct from the site for fiproles. We examined the binding site of BPBs in the adult housefly by means of radioligand-binding and electrophysiological experiments. 3-Benzamido-N-(2,6-dimethyl-4-perfluoroisopropylphenyl)-2-fluorobenzamide (BPB 1) (the N-demethyl BPB) was a partial, but potent, inhibitor of [(3)H]4\'-ethynyl-4-n-propylbicycloorthobenzoate (GABA channel blocker) binding to housefly head membranes, whereas the 3-(N-methyl)benzamido congener (the N-methyl BPB) had low or little activity. A total of 15 BPB analogs were tested for their abilities to inhibit [(3)H]BPB 1 binding to the head membranes. The N-demethyl analogs, known to be highly effective insecticides, potently inhibited the [(3)H]BPB 1 binding, but the N-methyl analogs did not even though they, too, are considered highly effective. [(3)H]BPB 1 equally bound to the head membranes from wild-type and dieldrin-resistant (rdl mutant) houseflies. GABA allosterically inhibited [(3)H]BPB 1 binding. By contrast, channel blocker-type antagonists enhanced [(3)H]BPB 1 binding to housefly head membranes by increasing the affinity of BPB 1. Antiparasitic macrolides, such as ivermectin B1a, were potent inhibitors of [(3)H]BPB 1 binding. BPB 1 inhibited GABA-induced currents in housefly GABARs expressed in Xenopus oocytes, whereas it failed to inhibit l-glutamate-induced currents in inhibitory l-glutamate receptors. Overall, these findings indicate that BPBs act at a novel allosteric site that is different from the site for channel blocker-type antagonists and that is probably overlapped with the site for macrolides in insect GABARs.
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