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Formononetin promotes angiogenesis through the estrogen receptor alpha-enhanced ROCK pathway
No full textFormononetin is an isoflavone that has been shown to display estrogenic properties and induce angiogenesis activities. However, the interrelationship between the estrogenic properties and angiogenesis activities of formononetin are not well defined. In the present study, docking and enzymatic assay demonstrated that formononetin displayed direct binding to the ligand-binding domain (LBD) of estrogen receptor alpha (ERα) with an agonistic property. Results from Human Umbilical Vein Endothelial Cells (HUVEC) by using real-time migration xCELLigence system, immunofluorescence and western blotting provided strong evidences of formononetin induced endothelial cell migration and dramatic actin cytoskeleton spatial modification through ERα-enhanced-ROCK-II/MMP2/9 signaling pathways. In addition, results from co-immunoprecipitation suggested formononetin induced cell migration via recruiting of ERα/ROCK-II activated complex formation. More interestingly, in zebrafish embryo we observed that formononetin significantly promoted angiogenic sproutings in the subintestinal vessels (SIVs) that could be completely abolished by ROCK inhibitor. In this study, we elucidated the underlying mechanisms that formononetin produced proangiogenesis effects through an ERα-enhanced ROCK-II signaling pathways. Results from the present study also expand our knowledge about the enigmatic underlying mechanisms of phytoestrogenic compounds in the promotion of angiogenesis in relation to ERα and ROCK interaction in endothelial cells and their relationship with actin assembly and cell migration
Chemical properties and bioactivities of Goji (Lycium barbarum) polysaccharides extracted by different methods
No full textLycium barbarum fruit (Goji or wolfberry) is widely used as a functional food as well as an herb in Chinese medicine. The polysaccharides of L. barbarum (LBPs) are well-known for immunomodulation and antioxidant activities. This study evaluated the yields, properties and bioactivities of LBPs extracted from L. barbarum fruit by different methods including hot water (HWE 100 °C), ultrasonic water (UWE 30–40 °C), subcritical water (SWE 110 °C), and ultrasound-enhanced subcritical water extraction (USWE 110 °C). The total LBP yield (80 min extraction followed by ethanol precipitation) was the highest from USWE (14% w/w) and the lowest from HWE (7.6%). The LBP from USWE also showed the highest protein (27.9%) and phenolic content (5.3%, w/w), and the highest antioxidant activities (scavenging radicals by DPPH and trolox equivalent antioxidant capacity assays; ferric reducing power). It also showed the highest immunoactivities in activating the phagocytosis and NO production of RAW264.7 macrophages. USWE was proven the most efficient method for extraction of LBPs. Temperature and ultrasound were two chief factors affecting the extraction yield, chemical properties and bioactivities of LBP
Health risk assessment of phthalate esters (PAEs) in drinking water sources of China
No full textPhthalate esters (PAEs) with endocrine disruption effects and carcinogenicity are widely detected in water environment. Occurrences of PAEs in source water and removal efficiencies of PAEs by drinking water treatment plants (DWTPs) in China were surveyed from publications in the last 10 years. Concentration of diethylhexyl phthalate (DEHP) in source water with median value of 1.3 μg/L was higher than that of dimethyl phthalate (DMP), diethyl phthalate (DEP), and di-n-butyl phthalate (DnBP). If the removal efficiencies of DEHP and DnBP reached 60 and 90 %, respectively, the calculated PAE concentration in drinking water can generally meet Standards for Drinking Water Quality in China. The health risks of PAEs, including non-carcinogenic and carcinogenic risks via the “water source-DWTP-oral ingestion/dermal permeation” pathway, were evaluated with Monte Carlo simulation and sensitivity analysis under certain removal efficiencies from 0 to 95 %. The carcinogenic risk of DEHP was lower than the upper acceptable carcinogenic risk level (10 −4 ), while the probability of DEHP’s carcinogenic risk between lower (10 −6 ) and upper (10 −4 ) acceptable carcinogenic risk level decreased from about 21.2 to 0.4 % through increasing DEHP removal efficiency from 0 to 95 %. The non-carcinogenic risk of DEHP was higher than that of DEP and DnBP. In all cases, the total non-carcinogenic risk of DEP, DnBP, and DEHP was lower than 1, indicating that there would be unlikely incremental non-carcinogenic risk to humans. Both carcinogenic risk and non-carcinogenic risk of PAEs in drinking water to female were a little higher than those to male
Mouthrinse effectiveness against Candida glabrata
No full textObjectives: To investigate the effectiveness of polyaminopropylbiguanide (ProntoLind), sodium chlorite (TheraBreath), povidone iodine (Betadine), Hamamelis virginiana extract (Systema), octenidine hydrochloride (Octenidol), chlorhexidine digluconate (Corsodyl), and essential oil mouthrinses (Listerine) against C. glabrata planktonic cells and biofilms.
Methods: Standardized inocula of C. glabrata ATCC 90030 were prepared and minimum inhibitory concentrations (MICs) of the mouthrinses were determined in accordance with Clinical and Laboratory Standards Institute (CLSI) Guidelines for the broth microdilution assay. Minimum fungicidal concentrations (MFCs) were determined by culturing optically clear wells. Mouthrinse efficacy against pre-formed biofilms was evaluated after one minute, and after five minutes of exposure.
Results: Octenidine hydrochloride and polyaminopropylbiguanide exhibited the highest MICs (1:2048 dilution), while the latter agent and chlorhexidine demonstrated fungicidal activity at 1:512 dilution. The essential oil exhibited significantly greater anti-biofilm activity (p≤0.002) than the other mouthrinses at an exposure time of one minute, with a 52% reduction in viable counts. Chlorhexidine reduced viable counts by 37%, and was significantly more effective than polyaminopropylbiguanide (p=0.001), sodium chlorite (p\u3e0.001), povidone iodine (p=0.001), Hamamelis virginiana extract (p
Conclusions: The essential oil mouthrinse exhibited the greatest anti-biofilm activity at both one and five minute exposure times. The standard rinsing time of one minute recommended by most commercial mouthrinse manufacturers may be insufficient for the reduction of C. glabrata
The symbolism of plants in the context of Hong Kong
No full textAs an integral part of our landscape, plants play important functional and aesthetic roles in our everyday life. Plants that appear in our landscape are reflective of the climatic and cultural contexts of where we live, in other words, our identity of place. In the context of Hong Kong, we encounter symbolic imageries of plants from both Eastern and Western contexts. Through a selection of plant symbols and by looking specifically at the ways they are depicted in works of Chinese literature, the worldviews expressed through such metaphorical associations are described. In so doing, this paper attempts to explore how these plant symbols may be interpreted in a contemporary context
群力勝天：戰前香港碼頭苦力與華人社區的管治
No full textThis monograph reconstructs the history of Hong Kong stevedores, as a group of Chinese population, and to observe its close connection with colonial governance over the Chinese population in Hong Kong. Hong Kong as a trade port has been relying on the human power of stevedores (addressed as coolies in Chinese language) to achieve economic prosperity. Stevedore was one of the core occupations of the Chinese lower class, which also highlighted its significance of representing the Chinese people. As an active group in colonial Hong Kong, stevedores struggled with government policies for better living and working conditions, again and again. The history of these ‘coolies’ can indicate the ground of government policies in particular stage. The research covers period from 1844 to 1945, by studying lives and work of stevedores, the research examines how this lower class of Chinese population interacted with the colonial government in different stages, and explores a variety of approaches for knowing about the stories of Hong Kong people in the past, and to provoke a reflection on the values and social justice of our home city
「翻轉教室」 奪A增兩成 學生睇片備課 上堂全討論
No full text2007年有美國教師提出「翻轉教室」（flipped classroom）教學模式，學生回家上網睇片備課，上課時間則用作討論及做功課，不再限於教師講書、學生抄筆記，此模式已在港萌芽。香港知專設計學院時裝及形象設計學系講師姚麗莉（Nina）是本港少數實行翻轉教室的教師，她打趣說「再沒學生打瞌睡了」，奪甲等成績的學生增加兩成。
Analysis of discourse practices in statistical computing laboratory
No full textClassroom talk plays a significant role in a teaching and learning process. The author of this paper was concerned with the way student-student and teacher-student discourses promotes students’ statistical thinking in the computing laboratory. An observation study was thus conducted to examine how social interactions among students in small groups and the teacher’s intervention were organised in the laboratory. In the observation study, verbal speech and peer interaction were audiotaped. The various discourses were transcribed in full, with relevant excerpts being selected for analysis within a Vygotskian framework. The student-student discourse was analysed with the aid of Kumpulainen’s framework. It was found that the high use of the organizational, judgmental as well as external thinking functions in the student talk when presenting the chart title and axis labels; approving or disapproving group mate’s work; and monitoring data entry actively during keyboard input respectively.
The teacher-student discourse was analysed with the aid of Tharp and Gallimore’s framework. Questioning was used frequently by the teacher to discover what the students knew, understood, or misunderstood, and to offer direction towards deeper thinking at times when students could not otherwise make progress on tasks. The teacher also used modelling assistance to help students see how to assemble and organise pieces of knowledge they might have already grasped or possessed. Contingency management was another form of assistance exhibited in the form of praise that affirmed the quality of students’ work. The teacher offered cognitive structuring that assisted them to organise and justify various aspects of a regression modelling problem but left room for students to regulate their strategies based on their own creation and interpretation of a regression model they found was the best
