Fatty acid ethyl esters in the liverwort Conocephalum conicum

A series of fatty acid ethyl esters ranging from C₁₄ to C₂₄ was isolated from a hexane extract of the liverwort Conocephalum conicum, these esters accounted for 77% of the extract. The ethyl esters consisting of even-numbered fatty acids were predominant and ethyl palmitate was the major constituent.     

A radioimmunoassay of plasma estradiol-17beta with the use of polyethylene glycol to separate free and antibody-bound hormone

A radioimmunoassay for plasma estradiol-17β was developed using polyethylene glycol to separate free from antibody-bound hormone. Specificity for estradiol-17β was achieved by a modified celite microcolunm procedure in which estradiol was.separated from interfering estrogens, including estrone. Using trace ³H-estradiol to monitor procedural losses, the method was shown to be sensitive and accurate. Intra- and inter-assay coefficient of variation of the method was 8.7 and 10.6%, respectively. Polyethylene glycol used for antibody precipitation appears to be a generally applicable method for steroid hormone radioimmunoassays. The simplicity, precision and rapid analysis, coupled with its lack of time dependence and ease in automation, makes this a convenient and practical method.     

Chemical constituents from Saussurea licentiana Hand.-Mazz

Chemical investigation of Saussurea licentiana led to the isolation of ten compounds, and their structures were identified to be dia-aurantiamide acetate (1), (+)-pinoresinol 4-O-β-D-glucoside (2), encelin (3), apigenin (4), luteolin (5), jaceosidin (6), luteolin -7-O-β-D- glucopyranoside (7), α-amyrin (8), β-amyrin (9), taraxasterol (10) on the basis of mass and NMR spectra. This is the first report on the occurrence of compounds 1, and 2 in the genus Saussurea while 1 is reported for the first time from Asteraceae. This work also represents the first phytochemical work on the whole plants of S. licentiana.     

Toward a Reversible Mn4+/Mn2+ Redox Reaction and Dendrite‐Free Zn Anode in Near‐Neutral Aqueous Zn/MnO2 Batteries via Salt Anion Chemistry

Rechargeable aqueous Zn/MnO₂ batteries are very attractive large‐scale energy storage technologies, but still suffer from limited cycle life and low capacity. Here the novel adoption of a near‐neutral acetate‐based electrolyte (pH ≈ 6) is presented to promote the two‐electron Mn⁴⁺/Mn²⁺ redox reaction and simultaneously enable a stable Zn anode. The acetate anion triggers a highly reversible MnO₂/Mn²⁺ reaction, which ensures high capacity and avoids the issue of structural collapse of MnO₂. Meanwhile, the anode‐friendly electrolyte enables a dendrite‐free Zn anode with outstanding stability and high plating/stripping Coulombic efficiency (99.8%). Hence, a high capacity of 556 mA h g^?1, a lifetime of 4000 cycles without decay, and excellent rate capability up to 70 mA cm^?2 are demonstated in this new near‐neutral aqueous Zn/MnO₂ battery by simply manipulating the salt anion in the electrolyte. The acetate anion not only modifies the surface properties of MnO₂ cathode but also creates a highly compatible environment for the Zn anode. This work provides a new opportunity for developing high‐performance Zn/MnO₂ and other aqueous batteries based on the salt anion chemistry.     

Enantiopure ethyl 2,3-dibromopropionate: Enantioselective synthesis vs preparative HPLC enantioseparation of racemate on multigram scale

Racemic ethyl 2,3-dibromopropionate, commercially available at low price, is a key intermediate used in the synthesis of several heterocycle fragments, which are present in many biologically active compounds. Surprisingly, the enantiomers are not commercially available and have never been described in the literature. In this work, we undertook two different strategies to obtain these enantiomers, which are enantioselective synthesis and preparative HPLC enantioseparation of commercially available racemate on multigram scale. The first strategy has proved inadequate because racemization occurred during the synthesis (ee ≈ 9-50%). Conversely, the second strategy produced a very good enantioseparation of commercially available racemate (ee > 99.5% for both enantiomers) on multigram scale.     

复方醋酸棉酚片联合独一味胶囊对大鼠无排卵型功能失调性子宫出血的改善作用及其作用机制

摘要 目的：探讨复方醋酸棉酚片联合独一味胶囊对大鼠无排卵型功能失调性子宫出血的改善作用及其作用机制。方法：将40只雌性SD大鼠随机均分成两组（空白组和模型组）,采用给大鼠连续21 d灌胃戊酸雌二醇的方法制备无排卵型功能失调性子宫大鼠模型。模型大鼠制备成功后,按随机法再均分成模型组、阳性组和治疗组,其中阳性组和治疗组分别灌胃给予相应的药物,空白组和模型组灌胃等体积的生理盐水,各组均连续灌胃7 d。计算各组大鼠的子宫系数,采用酶联免疫吸附法测定大鼠血清中雌二醇（estradiol, E₂）和孕酮（progestone,P）水平,采用免疫组化法测定大鼠子宫内膜组织中两个蛋白（matrix metalloproteinases-9,MMP-9和vascular endothelial growth factor ,VEGF）的表达量。结果：模型组大鼠血清中的P水平比空白组显著性减少（P<0.05）,子宫内膜组织中的MMP-9和VEGF表达量比空白组均显著性升高（P<0.05）。给药后,治疗组和阳性组大鼠血清中的P水平均显著高于模型组（P<0.05）,大鼠子宫内膜组织中的MMP-9和VEGF 表达量均显著低于模型组（P<0.05）,治疗组与阳性组之间无显著性差异（P >0.05）。结论：复方醋酸棉酚片联合独一味胶囊对无排卵型功能失调性子宫出血具有明显的改善作用,其机制可能与调控子宫内膜 MMP-9 和VEGF的表达量有关。     

Protective effect of quercetin on some hematological parameters in rats exposed to cadmium

ABSTRACT

We investigated the effects of quercetin (Q) on some hematological parameters and determined the percentage of alpha-naphthyl acetate esterase (ANAE) positive lymphocytes in rats that had been exposed to cadmium (Cd). Thirty male Wistar albino rats were divided into four groups: control (C), quercetin (Q), cadmium (Cd) and Q + Cd (CdQ). Blood samples were taken to assess erythrocytes (RBC), leukocytes (WBC), hemoglobin levels (Hb), hematocrit values (Hct), platelets (PLT), alpha-naphthyl acetate esterase (ANAE) positive lymphocytes. RBC, Hb, Hct; the number of PLT significantly decreased in the Cd group. To the contrary, these parameters were increased significantly in the CdQ group compared to the Cd group. Although we found a significant increase in total WBC count and neutrophil percentage, the number of lymphocytes decreased in the Cd group compared to the other three groups. Also, the percentage of peripheral blood ANAE positive lymphocytes decreased significantly in the Cd group (p < 0.05). Q exhibits positive effects on some hematological characteristics and the percentage of ANAE positive lymphocyte in cases of acute CD toxicity.