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1.
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon (PAH) in particulate matter that has a diameter of ≤2.5 μm (PM2.5). Studies have demonstrated that BaP exposure causes oocyte meiotic arrest in mice. However, whether BaP exposure also affects oocyte maturation in offspring remains unclear. To test this, female mice were administered BaP before pregnancy to generate BaP-exposed offspring. Our findings showed that BaP exposure reduced the in vitro maturation and increased the abnormalities of meiotic apparatus in offspring oocytes. In addition, BaP exposure reduced the mitochondrial content and intracellular ATP generation, induced early apoptosis, increased reactive oxidative species accumulation and the genomic DNA 5-methylcytosine (5mc) level in offspring oocytes. Along with the abovementioned defective parameters, maternal BaP exposure further compromised the embryo developmental competence of offspring oocytes. In summary, our study demonstrated that maternal BaP exposure compromised offspring oocyte maturation and quality.  相似文献   
2.
双环[1.1.1]戊烷(BCP)是一种具有三维立体结构的桥环骨架,其作为苯环、叔丁基和炔烃的生物电子等排体,已经在药物化学领域得到广泛的应用。随着BCP应用范围的扩大,BCP及其衍生物的合成日益成为研究的热点。本文对BCP衍生物的主要合成策略和方法进行总结,旨在为新药研发人员提供参考。  相似文献   
3.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents.  相似文献   
4.
In light of the pharmacophoric structural requirements for achieving anticonvulsant activity, a series of N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)benzamide (4a-g) and N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)-2-phenylacetamide (4h-n) derivatives were synthesized in two steps starting from the reaction of N-methyl isatoic anhydride with the appropriate hydrazide and followed by condensation with the appropriate aldehyde. The anticonvulsant activities of the synthesized compounds were evaluated according to the anticonvulsant drug development (ADD) programme protocol. Among the synthesized compounds, 4n showed promising activity in both the maximal electroshock (MES) and pentylenetetrazole (PTZ) tests with median effective dose (ED50) values of 40.7 and 6 mg/kg, respectively. The six most promising derivatives, 4b , 4a , 4c , 4f , 4j , and 4i , showed very low ED50 values in the PTZ test (3.1, 4.96, 8.68, 9.89, 12, and 13.53 mg/kg, respectively). All the tested compounds showed no to low neurotoxicity in the rotarod test with a wide therapeutic index. Docking studies of compound 4n suggested that GABAA binding could be the mechanism of action of these derivatives. The in silico drug likeliness parameters indicated that none of the designed compounds violate Lipinski's rule of five and that they are able to cross the blood–brain barrier.
Hit, Lead & Candidate Discovery
  相似文献   
5.
Condensation of thiourea 1 with diethyl malonate 2 in the presence of sodium methoxide furnished 4,6‐dihydroxy‐2‐mercaptopyrimidine 3 . Compound 3 on methylation with diazomethane followed by oxidation with H5IO6/CrO3 in ethyl acetate gave 4,6‐dimethoxy‐2‐methylsulphonylpyrimidine 5 . Compound 5 on condensation with 2‐mercapto‐6‐chlorobenzoic acid in the presence of a phase transfer catalyst, tetrabutylammonium bromide and sodium carbonate gave the title compound – pyrithiobac‐sodium 6 with an overall yield of > 35% starting from thiourea. Following the above standardized procedure, using [14C]‐thiourea in lieu of thiourea, 14C labelled product 6 , was synthesized with an overall radiochemical yield > 30% (with respect to [14C]‐thiourea) for further evaluations of environmental fate of 6 , in soils and plants. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
6.
During a period of twenty years [1969-1988] the author has observed 614 cases of congenital malformations and noninflammatory diseases of the larynx in infants and young children, Budapest. He summarizes the most characteristic symptoms of laryngeal pathology in infants, and discusses the diagnostic possibilities. Among the latter, spectrographic analyses complemented by auditory evaluation of pathological cry and different breathing noises play an important role. Based on his investigation author differentiates 20 kinds of pathological crying sounds and 4 basic forms of stridor. He describes the acoustic attributes of different pathological sound phenomena and summarizes characteristic voice changes.  相似文献   
7.
[(1R)‐endo]‐(+)‐3‐bromocamphor was dehalogenated with tritium gas to [3‐3H]camphor and via [3‐3H]phenylborneol converted to [3‐3H]deramciclane isolated as the fumarate salt (specific activity 51.8 GBq/mmol). This three step synthesis from [3‐3H]camphor gave an overall yield of 22%. Benzyloxy‐acetic acid methyl ester was reduced with sodium‐borotritide to 2‐benzyloxy‐ethanol‐[1‐3H], and through a four step procedure was converted to 2‐dimethylaminoethyl‐[2‐3H] chloride. The latter was condensed with the sodium derivative of 2‐phenylborneol giving rise to [2‐dimethylamino‐[2‐3H]ethoxy]deramciclane isolated as the fumarate (specific activity 8.177 GBq/mmol). This six step synthesis from [3H]NaBH4 gave an overall yield of 6%. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
8.
目的探讨复方醋酸环丙孕酮和罗格列酮序贯用药对改善多囊卵巢综合征(PCOS)患者生育功能的临床疗效。方法30例氯米芬抵抗的PCOS胰岛素抵抗患者,口服复方醋酸环丙孕酮3个月后,罗格列酮联合氯米芬用药6个月,比较用药前后体重指数、月经周期、生殖激素水平、排卵率、妊娠率、血糖和胰岛素水平的变化。结果与用药前相比,服用复方醋酸环丙孕酮后,雄激素水平和LH/FSH值明显降低(P〈0.05),服用罗格列酮后,胰岛素抵抗指数(Homa IR)、胰岛素分泌指数(Homa β)以及β细胞功能评定指数(MBCI)均较用药前降低(P〈0.05)。结论复方醋酸环丙孕酮和罗格列酮序贯用药可有效地抑制氯米芬抵抗的PCOS患者的高雄激素血症,改善胰岛素抵抗及生育功能。  相似文献   
9.
激素间歇冲击及小剂量维持治疗IgA肾病的随机对照研究   总被引:2,自引:2,他引:0  
目的:探讨激素间歇冲击及小剂量维持与血管紧张素转换酶抑制剂治疗中度蛋白尿IgA肾病的疗效及其影响因素。方法:47例IgA肾病患者随机分为实验组和对照组。对照组(21例)给予ACEI药物治疗,实验组(26例)在此基础上口服泼尼松0.5mg/kg,隔日给药,治疗12个月,并在治疗的第1、3、5个月初分别给予甲基泼尼松龙0.5g/d,冲击3d。对肾脏病理改变进行WHO分级并对各种病变进行半定量分析。结果:两组间在性别、年龄、临床及病理资料间无统计学差异。平均随访14个月后,实验组尿蛋白完全缓解8例(30.8%),部分缓解14例(53.8%),无缓解4例(15.4%);而对照组分别为4例(19.1%),3例(23.8%),12例(57.1%),有统计学差异(P<0.01)。治疗前后,实验组血肌酐分别为(89.9±30.3)μmol/L及(88.2±32.8)μmol/L;对照组分别为(89.5±37.9)μmol/L及(104.0±49.7)μmol/L,但两者比较均无统计学意义(P>0.05)。多因素分析显示疗效与肾小球硬化率及肾小管间质病变呈负相关。结论:激素间歇冲击及小剂量维持治疗能显著减少蛋白尿,维持肾功能稳定。影响疗效的主要因素为肾小球硬化率及肾小管间质病变程度。  相似文献   
10.
The endogenous hallucinogen, N,N-dimethyltryptamine (DMT), was labeled with carbon-11 and its regional distribution in rat brain studied. [11C]DMT showed higher accumulation in the cerebral cortex, caudate putamen, and amygdaloid nuclei. Studies of the subcellular distribution of [11C]DMT revealed the specific localization in the fractions enriched with serotonin receptors only when a very low dose was injected into rats. The proportions of the radioactivity in receptor-rich fractions were greatly enhanced by pretreatment with the monoamine oxidase inhibitor, pargyline. Specific binding of [11C]DMT to serotonin receptors in dog brain was demonstrated by a positron emission tomographic study in which 5-methoxy-N,N-dimethyltryptamine caused approximately 20% displacement of the radioligand from the receptors.  相似文献   
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