To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-（2,3-dibromo-4,5-dihydroxybenzyl）-2,3-dibromo-4,5-dihydroxy benzyl methyl eth...To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-（2,3-dibromo-4,5-dihydroxybenzyl）-2,3-dibromo-4,5-dihydroxy benzyl methyl ether （1）, （＋）-3-（2,3-dibromo-4,5-dihydroxyphenyl）-4-bromo-5,6-dihydroxy-1,3- dihydroisobenzofuran （2）, 3-bromo-4-（2,3-dibromo-4,5-dihydroxybenzyl）-5-methoxymethyl-pyrocatechol （3）, 2,2＇,3,3＇-tetrabromo-4,4＇,5,5＇-tetrahydroxy-diphenylmethane （4）, bis（2,3-dibromo-4,5-dihydroxybenzyl） ether （5）, 2,2＇,3-tribromo-3＇,4,4＇,5-tetrahydroxy-6＇-ethyloxymethyldiphenylmethane （6） were isolated from brown alga Leathesia nana, and their cytotoxicity were tested by MTF assays in human cancer cell lines A549, BGC-823, MCF-7, B16-BL6, HT-1080, A2780, Be17402 and HCT-8. Their inhibitory activity against protein tyrosine kinase （PTK） with over-expression of c-kit was analyzed also by ELISA. The antitumor activity of ethanolic extraction of Leathesia nana （EELN） was evaluated on S180-bearing mice. All compounds showed very potent cytotoxicity against all of the eight cancer cell lines with IC50 below 10 pg/mL. In PTK inhibition study, all bromophenol derivatives showed moderate inhibitory activity and compounds 2, 5 and 6 showed significant bioactivity with the inhibition ratio of 77.5%, 80.1% and 71.4% respectively. Pharmacological studies reveal that EELN could inhibit the growth of Sarcoma 180 tumor and increase the indices of thymus and spleen to improve the immune system remarkably in vivo. Results indicated that the bromophenol derivatives and EELN can be used as potent antitumor agents for PTK over-expression of c-kit and considered in a new therapeutic strategy for treatment of cancer.展开更多
The growth and interspecies competition of two red tide algal species Thalassiosira pseudonana Hasle et Heimdal and Gymnodinium sp. were studied under different concentration ratios of nitrogen to phosphorus, and the ...The growth and interspecies competition of two red tide algal species Thalassiosira pseudonana Hasle et Heimdal and Gymnodinium sp. were studied under different concentration ratios of nitrogen to phosphorus, and the algal hatch culture experiments were conducted. The physiological and biochemical indexes were measured periodically, including the maximum comparing growth rate, relative growth rate, average double time and chlorophyll a concentration. The results showed that when the concentration ratio of nitrogen to phosphorus was 16： 1, the maximum comparing growth rate, relative growth rate and chlorophyll a concentration of Thalassiosira pseudonana all reached the highest,and average double time was the shortest. This implied that the optimal concentration ratio of nitrogen to phosphorus of Thalassiosira pseudonana is 16： 1. When the concentration ratio of nitrogen to phosphorus was 6：1, the maximum comparing growth rate, relative growth rate and the chlorophyll a concentration of Gymnodinium sp. reached the highest, and average double time was the shortest, so the optimal concentration ratio of nitrogen to phosphorus of Gymnodinium sp. is 6： 1. From the growth curves as indicated both in the cell density and the chlorophyll a concentration, it is suggested that the influence of concentration ratio of nitrogen to phosphorus on the chlorophyll a concentration and the cell density are almost the same. Different concentration ratios of nitrogen to phosphorus had weak influence on community succession and the competition between the two algae. Gymnodinium sp. may use the phosphorus in vivo for growth, so it is important to pay attention to the concealment of phosphorus, in order to avoid the outbreak of red tide. On the basis of the importance of nitrogen and phosphorus and the ratio of their concentration, the possible outbreak mechanism of red tide of the two algae was also discussed.展开更多
Objective:To assess the prevalence of parasitic infections among patients attending Saint Camille Medical Centre and to estimate co-parasitic infections rates.Methods:From January to December 2009,stool samples were c...Objective:To assess the prevalence of parasitic infections among patients attending Saint Camille Medical Centre and to estimate co-parasitic infections rates.Methods:From January to December 2009,stool samples were collected from 11 728 persons,aged from five months to 72 years and suffering from gastroenteritis.After macroscopic description,the stools were examined by light microscopy to search for the presence of parasites.Results:From the 11 728 analyzed stools,6 154(52.47%) were infected with at least one parasite.Protozoan frequently encountered were:Giardia intestinalis(43.47%),Entamoeba histolytica/Entamoeba dispar(30.74%) and Trichomonas irUestinalis(21.72%),while Hymenolepis nana(2.25%) was the most common helminth.Co-infections occurred in 22.34%cases.Within the multi-infected samples,dual and triple infections accounted for 71.18%and 20.00%,respectively.Giardia irUestinalis for protozoan and Hymenolepis nana for helminths were the most implicated co-infections.Conclusions: This study confirms that intestinal parasites are still a public health problem in Burkina Faso.To reduce the incidence of parasitic infections,it is necessary to promote the education of people so that they practice the rules of individual and collective hygiene.展开更多
A novel bromophenol was isolated from ethanolic extract of the brown alga Leathesia nana S.et G. The structure was elucidated as (E)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methyl-propenal by spectroscopic methods inclu...A novel bromophenol was isolated from ethanolic extract of the brown alga Leathesia nana S.et G. The structure was elucidated as (E)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methyl-propenal by spectroscopic methods including IR, HREIMS, 1D and 2D NMR techniques.展开更多
Since ancient times, as one of the symbols of ugly and dirty, prostitutes are invariably living in the black margins of society. Facing prostitutes'miseries, people always can not understand their emotions, mental...Since ancient times, as one of the symbols of ugly and dirty, prostitutes are invariably living in the black margins of society. Facing prostitutes'miseries, people always can not understand their emotions, mentalities and desires, or treats them as equals, particularly as women. Prostitutes are a special group in the oppressed women in Western societies. Margaret and Nana are two typical images of them in the history of western literature. With tears and lives, they deduce their miserable life stories similarly.展开更多
基金Supported by the National High Technology Research and Development Program of China (863 Program, No. 2007AA09Z410)Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-209)
文摘To investigate the antitumor effect of bromophenol derivatives in vitro and Leathesia nana extract in vivo, six bromophenol derivatives 6-（2,3-dibromo-4,5-dihydroxybenzyl）-2,3-dibromo-4,5-dihydroxy benzyl methyl ether （1）, （＋）-3-（2,3-dibromo-4,5-dihydroxyphenyl）-4-bromo-5,6-dihydroxy-1,3- dihydroisobenzofuran （2）, 3-bromo-4-（2,3-dibromo-4,5-dihydroxybenzyl）-5-methoxymethyl-pyrocatechol （3）, 2,2＇,3,3＇-tetrabromo-4,4＇,5,5＇-tetrahydroxy-diphenylmethane （4）, bis（2,3-dibromo-4,5-dihydroxybenzyl） ether （5）, 2,2＇,3-tribromo-3＇,4,4＇,5-tetrahydroxy-6＇-ethyloxymethyldiphenylmethane （6） were isolated from brown alga Leathesia nana, and their cytotoxicity were tested by MTF assays in human cancer cell lines A549, BGC-823, MCF-7, B16-BL6, HT-1080, A2780, Be17402 and HCT-8. Their inhibitory activity against protein tyrosine kinase （PTK） with over-expression of c-kit was analyzed also by ELISA. The antitumor activity of ethanolic extraction of Leathesia nana （EELN） was evaluated on S180-bearing mice. All compounds showed very potent cytotoxicity against all of the eight cancer cell lines with IC50 below 10 pg/mL. In PTK inhibition study, all bromophenol derivatives showed moderate inhibitory activity and compounds 2, 5 and 6 showed significant bioactivity with the inhibition ratio of 77.5%, 80.1% and 71.4% respectively. Pharmacological studies reveal that EELN could inhibit the growth of Sarcoma 180 tumor and increase the indices of thymus and spleen to improve the immune system remarkably in vivo. Results indicated that the bromophenol derivatives and EELN can be used as potent antitumor agents for PTK over-expression of c-kit and considered in a new therapeutic strategy for treatment of cancer.
文摘The growth and interspecies competition of two red tide algal species Thalassiosira pseudonana Hasle et Heimdal and Gymnodinium sp. were studied under different concentration ratios of nitrogen to phosphorus, and the algal hatch culture experiments were conducted. The physiological and biochemical indexes were measured periodically, including the maximum comparing growth rate, relative growth rate, average double time and chlorophyll a concentration. The results showed that when the concentration ratio of nitrogen to phosphorus was 16： 1, the maximum comparing growth rate, relative growth rate and chlorophyll a concentration of Thalassiosira pseudonana all reached the highest,and average double time was the shortest. This implied that the optimal concentration ratio of nitrogen to phosphorus of Thalassiosira pseudonana is 16： 1. When the concentration ratio of nitrogen to phosphorus was 6：1, the maximum comparing growth rate, relative growth rate and the chlorophyll a concentration of Gymnodinium sp. reached the highest, and average double time was the shortest, so the optimal concentration ratio of nitrogen to phosphorus of Gymnodinium sp. is 6： 1. From the growth curves as indicated both in the cell density and the chlorophyll a concentration, it is suggested that the influence of concentration ratio of nitrogen to phosphorus on the chlorophyll a concentration and the cell density are almost the same. Different concentration ratios of nitrogen to phosphorus had weak influence on community succession and the competition between the two algae. Gymnodinium sp. may use the phosphorus in vivo for growth, so it is important to pay attention to the concealment of phosphorus, in order to avoid the outbreak of red tide. On the basis of the importance of nitrogen and phosphorus and the ratio of their concentration, the possible outbreak mechanism of red tide of the two algae was also discussed.
文摘Objective:To assess the prevalence of parasitic infections among patients attending Saint Camille Medical Centre and to estimate co-parasitic infections rates.Methods:From January to December 2009,stool samples were collected from 11 728 persons,aged from five months to 72 years and suffering from gastroenteritis.After macroscopic description,the stools were examined by light microscopy to search for the presence of parasites.Results:From the 11 728 analyzed stools,6 154(52.47%) were infected with at least one parasite.Protozoan frequently encountered were:Giardia intestinalis(43.47%),Entamoeba histolytica/Entamoeba dispar(30.74%) and Trichomonas irUestinalis(21.72%),while Hymenolepis nana(2.25%) was the most common helminth.Co-infections occurred in 22.34%cases.Within the multi-infected samples,dual and triple infections accounted for 71.18%and 20.00%,respectively.Giardia irUestinalis for protozoan and Hymenolepis nana for helminths were the most implicated co-infections.Conclusions: This study confirms that intestinal parasites are still a public health problem in Burkina Faso.To reduce the incidence of parasitic infections,it is necessary to promote the education of people so that they practice the rules of individual and collective hygiene.
文摘A novel bromophenol was isolated from ethanolic extract of the brown alga Leathesia nana S.et G. The structure was elucidated as (E)-3-(2,3-dibromo-4,5-dihydroxyphenyl)-2-methyl-propenal by spectroscopic methods including IR, HREIMS, 1D and 2D NMR techniques.
文摘Since ancient times, as one of the symbols of ugly and dirty, prostitutes are invariably living in the black margins of society. Facing prostitutes'miseries, people always can not understand their emotions, mentalities and desires, or treats them as equals, particularly as women. Prostitutes are a special group in the oppressed women in Western societies. Margaret and Nana are two typical images of them in the history of western literature. With tears and lives, they deduce their miserable life stories similarly.
基金supported by the National Natural Science Foundation of China(Grant No.31900180,31970223)the Natural Science Foundation of Yunnan Province(Grant No.202101AT070058)+1 种基金the Project of Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences(Grant No.Y4ZK111B01)the Lancang-Mekong Cooperation(LMC)Special Fund.
