The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, ...The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, etc. were identified. The analysis revealed that the diurnal rhythm of release of volatile compounds from maple differed in July and in August. In July, the releasing of most volatile compounds reached the peak at 14 o'clock, when in August, the emission of volatile compounds reached the peak at 10 o'clock. Besides diurnal rhythm, there also existed other differences in the releasing of volatiles and their relative contents in July and in August. A possible explanation for this phenomenon is the maturation of leaves, since the sampling conditions were the same both in July and August. At the same time, the response of Anoplophora glabrpennis Motschulsky to volatiles was examined with field bioassay with traps. cis-3-hexen-1-ol was found to be more effective to attract A. glabrpennis than other volatiles released by ash-leaf maple tree in field trapping test. A mixture of 1-butanol, 1-pentanol and 2-pentanol was tested to be the most attractive to A. glabripennis among all tested volatiles. More field trapping tests should be conducted.展开更多
Idiopathic hypogonadotropic hypogonadism is a rare disease that is characterized by delayed/absent puberty and/or infertility due to an insufficient stimulation of an otherwise normal pituitary-gonadal axis by gonadot...Idiopathic hypogonadotropic hypogonadism is a rare disease that is characterized by delayed/absent puberty and/or infertility due to an insufficient stimulation of an otherwise normal pituitary-gonadal axis by gonadotrophin-releasing hormone （GnRH） action. Because reduced or normal luteinizing hormone （LH）/follicle-stimulating hormone （FSH） levels may be observed in the affected patients, the term idiopathic central hypogonadism （ICH） appears to be more appropriate. This disease should be distinguished from central hypogonadism that is combined with other pituitary deficiencies. Isolated ICH has a complex pathogenesis and ~s fivefold more prevalent in males. ICH frequently appears in a sporadic form, but several familial cases have also been reported. This finding, in conjunction with the description of numerous pathogenetic gene variants and the generation of several knockout models, supports the existence of a strong genetic component. ICH may be associated with several morphogenetic abnormalities, which include osmic defects that, with ICH, constitute the cardinal manifestations of Kallmann syndrome （KS）. KS accounts for approximately 40% of the total ICH cases and has been generally considered to be a distinct subgroup. However, the description of several pedigrees, which include relatives who are affected either with isolated osmic defects, KS, or normo-osmic ICH （nlCH）, justifies the emerging idea that ICH is a complex genetic disease that is characterized by variable expressivity and penetrance. In this context, either multiple gene variants or environmental factors and epigenetic modifications may contribute to the variable disease manifestations. We review the genetic mechanisms that are presently known to be involved in ICH pathogenesis and provide a clinical overview of the 227 cases that have been collected by the collaborating centres of the Italian ICH Network.展开更多
文摘The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, etc. were identified. The analysis revealed that the diurnal rhythm of release of volatile compounds from maple differed in July and in August. In July, the releasing of most volatile compounds reached the peak at 14 o'clock, when in August, the emission of volatile compounds reached the peak at 10 o'clock. Besides diurnal rhythm, there also existed other differences in the releasing of volatiles and their relative contents in July and in August. A possible explanation for this phenomenon is the maturation of leaves, since the sampling conditions were the same both in July and August. At the same time, the response of Anoplophora glabrpennis Motschulsky to volatiles was examined with field bioassay with traps. cis-3-hexen-1-ol was found to be more effective to attract A. glabrpennis than other volatiles released by ash-leaf maple tree in field trapping test. A mixture of 1-butanol, 1-pentanol and 2-pentanol was tested to be the most attractive to A. glabripennis among all tested volatiles. More field trapping tests should be conducted.
文摘Idiopathic hypogonadotropic hypogonadism is a rare disease that is characterized by delayed/absent puberty and/or infertility due to an insufficient stimulation of an otherwise normal pituitary-gonadal axis by gonadotrophin-releasing hormone （GnRH） action. Because reduced or normal luteinizing hormone （LH）/follicle-stimulating hormone （FSH） levels may be observed in the affected patients, the term idiopathic central hypogonadism （ICH） appears to be more appropriate. This disease should be distinguished from central hypogonadism that is combined with other pituitary deficiencies. Isolated ICH has a complex pathogenesis and ~s fivefold more prevalent in males. ICH frequently appears in a sporadic form, but several familial cases have also been reported. This finding, in conjunction with the description of numerous pathogenetic gene variants and the generation of several knockout models, supports the existence of a strong genetic component. ICH may be associated with several morphogenetic abnormalities, which include osmic defects that, with ICH, constitute the cardinal manifestations of Kallmann syndrome （KS）. KS accounts for approximately 40% of the total ICH cases and has been generally considered to be a distinct subgroup. However, the description of several pedigrees, which include relatives who are affected either with isolated osmic defects, KS, or normo-osmic ICH （nlCH）, justifies the emerging idea that ICH is a complex genetic disease that is characterized by variable expressivity and penetrance. In this context, either multiple gene variants or environmental factors and epigenetic modifications may contribute to the variable disease manifestations. We review the genetic mechanisms that are presently known to be involved in ICH pathogenesis and provide a clinical overview of the 227 cases that have been collected by the collaborating centres of the Italian ICH Network.
