Osteogenic potential of a chalcone in a critical-size defect in rat calvaria bone

BackgroundThis study describes the bone formation stimulated by the application of a type of chalcone to critical-size defects in rat calvarial bone.Material and methodsSixty female Wistar rats were divided into 6 groups of 10 animals per group: control (no treatment), vehicle (vaseline) and the chalcone (1-phenyl-3-(4-chlorophenyl)-2-propen-1-one) suspended in vaseline at 10%. A critical-size defect of 5 mm was prepared using a trephine in the calvarial bone, after which the treatment was applied, in a single dose, according to the experimental group. The samples were evaluated macroscopically using ImageJ software, and histologically 30 and 45 days after surgery.ResultsAt 30 days after surgery, there was significant bone formation (p < 0.05) in the groups treated with chalcone, compared with the other groups. Many active osteoblasts were observed adjacent to the borders of the newly formed bone tissue. 45 days after surgery in the chalcone group, the surgical defects showed complete bone closure.ConclusionThe results of this study suggest that chalcone has significant potential to induce the formation of new bone.     

苦蘵内生真菌Trichoderma harzianum的次级代谢产物

目的:研究茄科酸浆属植物苦蘵(Physalis angulata)的内生真菌哈茨木霉(Trichoderma harzianum)的次级代谢产物。方法:菌株采用震荡培养箱扩大培养,得到的菌液用乙酸乙酯等体积萃取3次,菌丝体则以丙酮浸泡超声,回收溶剂后将所得提取物合并,再经液相-质谱联用技术,开放ODS反相柱色谱,LH-20羟丙基葡聚糖凝胶柱色谱(sephadex LH-20),高效液相色谱等方法进行成分的分析与分离纯化活性次级代谢产物。利用其理化性质和光谱数据(~1H-NMR,~(13)C-NMR)等鉴定化合物结构。采用噻唑蓝(MTT)法测定化合物的细胞毒性。结果:从苦蘵内生真菌哈茨木霉中分离得到10个次级代谢产物,分别鉴定为destruxin A_2(1),destruxin B_2(2),环(亮-脯)二肽(3),环(苯丙-脯)二肽(4),cyclonerodiol(5),brevianamide F(6),N-乙酰色胺(7),9-羟基-邻苯二甲酸二异丁基酯(8),5-羟基-3-羟甲基-2-甲基-7-甲氧基色酮(9)和苯丙酸(10)。细胞毒性试验结果显示,化合物1～10对肺癌细胞株A549均未表现出显著的细胞毒性(半抑制浓度≥20 mg·L~(-1))。结论:化合物1～10均首次从哈茨木霉中分离得到。     

A mitochondria-targeted ratiometric fluorescent probe to monitor endogenously generated sulfur dioxide derivatives in living cells

Sulfur dioxide (SO₂) can be endogenously produced by enzymes in mitochondria during oxidation of H₂S or sulphur-containing amino acids, and plays important roles in several physiological processes. However, the design and synthesis of fluorescent probes which can detect mitochondrial SO₂ and its derivatives in living cells still remain unresolved. Herein, we report the preparation of a lipophilic cationic dye 1 (Mito-Ratio-SO₂), which targets the mitochondria in living cells and is sensitive to the presence of SO₂ derivatives. The ratiometric probe Mito-Ratio-SO₂ displays a 170 nm blue-shift in emission with two well-resolved emission bands upon addition of sulfite. Mechanistic studies indicate that three probe-SO₂ adducts coexist after reaction, as supported by liquid chromatography and density function theory investigations. Importantly, the ratiometric probe is highly selective for sulfite over other bio-species including H₂S. Fluorescence co-localization studies indicate that the probe localizes solely in the mitochondria of HeLa cells. Last but not least, fluorescent imaging of HeLa cells successfully demonstrates the detection of intrinsically generated intracellular SO₂ derivatives in living cells.     

Complete Tibial Aplasia with Preaxial Polydactyly: A Kindred of Affected Individuals in three Generations

Tibial aplasia with polydactyly of hands and feet is a rare congenital anomaly, affecting both sexes with reported prevalence between 5 and 19 per 10000 live births⁽¹⁾. The molecular basis of this defect is unknown, and autosomal dominant mode of inheritance ^(2,3,4,5,6) with variable expressivity is usually postulated.The first case, more or less similar to the aforesaid phenotype, was reported in 1915 by Werner⁽⁷⁾ in a 20 yrs old woman in her 6^th months of pregnancy; and in 1918 Davidson⁽⁸⁾ reported the second case, in a two yrs old baby. This type of congenital anomaly, reported by Werner and Davidson, is commonly referred to as Werner's syndrome⁽⁷⁾, or, Werner mesomelic syndrome⁽⁷⁾, or, Eaton-McKusick syndrome⁽⁹⁾. The first familial case of Werner type was reported by Reber (1968)⁽¹⁰⁾, and second familial case was reported by Eaton and McKusick(1969)⁽⁹⁾. Latter similar cases with familial inheritance were reported by various authors^(2,4,5); which suggests the variable expressivity and autosomal dominant mode of inheritance of this sort of congenital malformations. Gene responsible for preaxial polydactyly associated with tibial dysplasia/ aplasia, has been localized to chrosome 7q36⁽¹⁾.Very few cases are reported in India, and even fewer from our region. Here we report a case of a newborn on day-1, admitted in nursery with polydactyly of both upper and lower limbs, along with unilateral limb shortening and bilateral congenital talipes-equinovarus(CTEV); and also similar limb defects in the same family members spanning three generations.     

Facile one-pot synthesis of sulfonyl fluorides from sulfonates or sulfonic acids

A facile cascade process for directly transforming the abundant and inexpensive sulfonates (or sulfonic acids) to the highly valuable sulfonyl fluorides was developed. This new protocol features mild reaction conditions using readily available and easy-to-operate reagents. A diverse set of sulfonyl fluorides was prepared facilitating the enrichment of the sulfonyl fluoride library.

A mild one-pot protocol for directly converting sulfonates or sulfonic acids into sulfonyl fluorides was developed.

Sulfonyl fluorides (SFs) have been identified and utilized in the realms of biology, pharmaceuticals and functional molecules for their unique stability-reactivity balance.¹ Owing to the relatively low reactivity toward nucleophilic substitution and the exclusive heterolytic property, SF electrophiles are privileged motifs in the selective covalent interaction with context-specific amino acids or proteins for diverse applications (Fig. 1).² For example, Murthy and co-workers disclosed that 2-nitrobenzenesulfonyl fluoride (NBSF, Fig. 1) was effective at killing Gram-negative bacteria, where the SF group could possibly react with target proteins directly or via an intermediate.³ By holding a compatible electrophilicity, SFs have found remarkable utility as covalent probes in chemical biology, which enable the efficient targeting of active-site amino acid residues.^2,4 Meanwhile, through the reaction of SFs with active site amino acids to inactivate these enzymes, the corresponding SF-type protease inhibitors could be developed.⁵ The commonly used serine protease inhibitors include (2-aminoethyl)benzenesulfonyl fluoride (AEBSF, Fig. 1), of which the hydrochloride salt is called Pefabloc®.^5a,c In addition, the diagnostic value of SF in ¹⁸F-labelled biomarkers in positron emission tomography has also drawn much attention, such as the application of [¹⁸F]4-formylbenzenesulfonyl fluoride ([¹⁸F]FBSF, Fig. 1) as a radio labeling synthon.⁶Open in a separate windowFig. 1Representative sulfonyl fluoride-containing molecules with significant biological values.Despite the versatile findings on the utility of SFs, the efforts toward their synthesis often encountered sluggishness. The most common method involves a chlorine–fluorine exchange of arenesulfonyl chloride in the presence of aqueous solution of KF⁷ or KHF₂ (ref. 8) (Scheme 1a). A more efficient system could be achieved with phase transfer catalyst including KF and 18-crown-6-ether in acetonitrile.⁹ However, the generated sulfonyl chloride intermediates as very reactive electrophiles, are easily subjected to nucleophilic attack without selectivity thus are considered as poor candidates in the synthetic sequence of complex molecules. To alleviate this issue, a pd-catalysed strategy through the insertion of SO₂ to Ar–X for assembly of ArSO₂F was introduced (Scheme 1b).¹⁰ As a continuation of our search for general and practical protocols for the synthesis of sulfonyl fluoride motifs,¹¹ we attempted to use the stable and readily available sulfonates as starting material. In fact, a successful exploration on sulfonate as raw material has been conducted by Sharpless and co-workers, unveiling a two-step synthesis of SFs comprising the initial preparation of sulfonyl chloride by reacting sulfonate with chlorosulfuric acid, and subsequent chlorine–fluorine exchange to form S^VI-F,^1a whereas the use of toxic chlorosulfuric acid inevitably raises the safety risk. On the other hand, DAST (diethyl amino sulfur trifluoride), XtalFluor-M (difluoro-4-morpholinylsulfonium''tetrafluoroborate) and related reagents were also reported for fluorination reactions, however, these reagents have rarely been successfully applied for the synthesis of sulfonyl fluorides.^12a,b Comparing with DAST, KHF₂ is an inexpensive, stable, and industrially applicable chemical acting as both nucleophile and buffer for the preparation of sulfonyl fluorides.^12c,d Herein, we report the transition-metal-free one-pot synthesis of SFs from sulfonates in the presence of cyanuric chloride and KHF₂ (Scheme 1c). Phase transfer catalyst tetra-n-butylammonium bromide (TBAB) was selected for the transformation of sulfonates, while tetramethylammonium chloride (TMAC) was used for the case of sulfonic acid.Open in a separate windowScheme 1Strategies for the assembly of sulfonyl fluorides.The preparations of SFs from sulfonate salts^1a,13,14 are rarely reported and could date back to Kulka''s work over sixty years ago (or even earlier), and therein chlorosulfuric acid (occasionally oxalyl chloride) is essential for the provisional forming of S^VI-Cl, followed by chlorine-fluorine transformation in a separated step to produce S^VI-F. The chlorination process is regarded as the pivotal step, which normally requires harsh conditions. From a practical point of view, the convenient handling of the stable and nontoxic raw materials is particularly advantageous. Therefore, our focus is addressed on the efficient transformations of sulfonate with readily available and easy-handling reagents to install SF group. Cyanuric chloride (2) is usually used as an alternative to oxalyl chloride in the Swern oxidation,¹⁵ which may also be effective in the preparation of sulfonyl chloride. To verify this hypothesis, our preliminary study was set out for reaction condition screening (16 it seems that the present system is also feasible (the detailed study of solvent screening can be found in ESI^†). Then, a series of fluoride salts as F⁻ source were screened. To be expected, potassium bifluoride showed superior activity compared to other fluoride salts (entries 8–11,

蒲公英乙酸乙酯部位化学成分研究

目的：研究蒲公英乙酸乙酯部位的化学成分。方法：采用渗漉法提取蒲公英有效成分,硅胶柱层析、反相高效液相色谱法及半制备高效液相色谱法对提取物进行分离和纯化,依据单体化合物的理化性质及核磁共振谱图确定其化学结构。结果：从蒲公英乙酸乙酯部位分离得到6个化合物,分别是棕榈酸（Ⅰ）、咖啡酸（Ⅱ）、咖啡酸乙酯（Ⅲ）、对羟基苯乙酸乙酯（Ⅳ）、阿魏酸（Ⅴ）和blumenol A （Ⅵ）。结论：化合物Ⅵ为首次从蒲公英中分离得到。     

Hypolipidemic and antioxidant effects of mulberry (Morus alba L.) fruit in hyperlipidaemia rats

The phytochemical constituents of a freeze-dried powder of mulberry (Morus alba L.) fruit (MFP) were determined. The hypolipidemic and antioxidant effects of the MFP as a dietary supplement were evaluated in rats who were fed 4 weeks of either a high-fat or a normal diet supplemented with 5% or 10% MFP. Administration of MFP to rats on a high-fat diet resulted in a significant decline in levels of serum and liver triglyceride, total cholesterol, serum low-density lipoprotein cholesterol, and a decrease in the atherogenic index, while the serum high-density lipoprotein cholesterol was significantly increased. In addition, the serum and liver content of thiobarbituric acid related substances, a lipid peroxidation product, significantly decreased, while the superoxide dismutase (SOD) of red blood cell and liver, as well blood glutathione peroxidase (GSH-Px) activities significantly increased. No significant changes in lipid profile in the serum and liver were observed in rats on a normal diet supplemented with MFP, but blood and liver antioxidant status improved, as measured by SOD and GSH-Px activity, and lipid peroxidation was reduced. These beneficial effects of MFP on hyperlipidaemia rats might be attributed to its dietary fiber, fatty acids, phenolics, flavonoids, anthocyanins, vitamins and trace elements content.     

木瓜无公害栽培技术探讨

木瓜是我国传统中药,来源于蔷薇科植物贴梗海棠[Chaenomeles speciosa (Sweet) Nakai]的干燥近成熟果实,具有平肝舒筋、和胃化湿的功效。随着可用林地的逐步限制,农田栽培将成为木瓜种植产业发展的主要模式,而无公害生产是未来木瓜产业发展的主要方向。通过多年农田种植木瓜研究数据及产区调研结果,该文制订了木瓜无公害生产标准操作规程。该规程包括木瓜无公害栽培环境选择、无公害种植方法、田间管理、病虫害防治及质量控制等内容。该文提出培育适宜农田栽培的优质新品种,建立病虫害综合防治平台等技术措施,以促进木瓜农田种植产业的健康可持续发展。