In order to better understand shrimp allergen,some basic characters of the major allergen of greasy-back shrimp(Metapenaeus ensis)were investigated.The major allergen was extracted and separated,and its peptide mass f...In order to better understand shrimp allergen,some basic characters of the major allergen of greasy-back shrimp(Metapenaeus ensis)were investigated.The major allergen was extracted and separated,and its peptide mass fingerprint(PMF)wasanalyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS).After screening inthe NCBI database with Mascot searching engine,the results indicated that the major allergen of greasy-back shirmp was muscletropomyosin.Database matching search showed that the top protein matched,i.e.the tropomyosin from giant tiger prawn(Penaeusmonodon),had a Mowse value of 268.In addition,there were 27 queries matched with the allergen in greasy-back shirmp with anamino acid sequence coverage value of 65%.The matching scores and the sequence coverage values were also high with tropomy-osins of other invertebrates,including Tyrophagus putrescentiae and Lepisma saccharina.These results indicated that the allergen ofMetapenaeus ensis had high homology with other crustacean allergens,and provided molecular explanations for the highcross-reactivity of the major allergens between crustaceans and some other invertebrates.展开更多
A novel hasubanan alkaloid has been isolated along with the known aknadinine from the fresh roots of Stephania sutchenensis.Its structure has been established as 1—nitroaknadinine from detailed spectral studies and c...A novel hasubanan alkaloid has been isolated along with the known aknadinine from the fresh roots of Stephania sutchenensis.Its structure has been established as 1—nitroaknadinine from detailed spectral studies and confirmed by chemical correlation with aknadinine.The novel alkaloid is the first nitro-hasubanan and also the first example of naturally occurring nitro—alkaloids.展开更多
This study reports the variation of residual strains within the posterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this ...This study reports the variation of residual strains within the posterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this structure exhibits a tensile strain, in contrast to a compressive strain observed within the inner layer. Fluctuations in unit cell parameters for the inner layer have been determined, showing that the microscopic prismatic layer of the structure exhibits a compressive strain orientated parallel to the surface of the shell. This is thought to enhance the crack deflection properties of this layer, and aid in resisting catastrophic failure. Further analysis of residual strains has been performed using the same method, throughout several stages of compressive testing of the anterior dorsal region of the shell. This identified no variation in residual strains at various levels of loading, and it is therefore proposed that load may be transferred via the organic matrix of mollusc shell structures. A Raman spectroscopic investigation, comparing whole and powdered shell with non-biogenic aragonite, has shown that residual strains are also present in this analagous material which is devoid of organic content. This indicates that the observed strain is not entirely due to the organic matrix.展开更多
By using immunocytochemistry method of Strept Avidin-Biotin-Complex, four kinds of antisera raised against rabbits were applied to observe the immunoreactive neurons and neuropils of sero-tonin (5-HT), neuropeptide Y ...By using immunocytochemistry method of Strept Avidin-Biotin-Complex, four kinds of antisera raised against rabbits were applied to observe the immunoreactive neurons and neuropils of sero-tonin (5-HT), neuropeptide Y (NPY), substance P (SP) and β-Endorphin (β-Ep) in optic ganglia and brain of Metapenaeus ensis. The results showed that, the 5-HT-immunoreactive cells were located in all the four neuropils of optic ganglia. Immunoreactivity of 5-HT was detected in anterior medial protocerebrum neuropils (AMPN), and the inner and outer lateral beside olfactory lobe (OL) of deutocerebrum. The presence of NPY-immunoreactive cells was found in all the four neuropils of the optic ganglia. NPY-immunoreactivity occurred in the anterior median cell cluster, lateral cell cluster of protocerebrum, and cell cluster beside OL and AMPN. SP-immunoreactivity was found in medulla terminalis (MT) of optic ganglia, and lateral cell cluster of protocerebrum and posterior lateral cell cluster of tritocerebrum. β-Ep-immunoreactive cells were in MT only. In conclusion, these specific distribution patterns of the four immunoreactive substances can be used as morphological clues for understanding their different neuro-physiological functions.展开更多
The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This is the case of Aubregrinia taïensis (Aubrév. & Pell...The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This is the case of Aubregrinia taïensis (Aubrév. & Pellegr.) Heine, a critically endangered Sapotaceae species, endemic to Côte d’Ivoire and Ghana. After 3 years of investigation in and around the Tai National Park (TNP) in the West of Côte d’Ivoire, only one individual of this species was located and no sexual reproductive organs (fruits, seeds) were observed. Woody plant species around this individual were inventoried in order to know the species that can co-occur with Aubregrinia taïensis. For that a plot of 30 m of diameter was established around the individual and all of the woody species of this circle were inventoried. Then, the taxonomic diversity, the chorology of the species, the conservation status and their life-form were recorded. A total of 130 woody plant species belonging to 51 families were collected in the site. The most represented families are Euphorbiaceae (12 spp.), Rubiaceae (10 spp.), Annonaceae (7 spp.), Fabaceae, Moraceae, Malvaceae (6 spp. each) while the most represented genera are Diospyros L. (4 spp.), Cola Schott & Endl. and Vitex L. (3 spp.). Species from the Guineo-Congolese Region (GC) are the most abundant (72%). They are followed by West African endemic species (GCW, 19%). Microphanerophytes (mp) are the most abundant and represent more than 40% of the species. Three vulnerable species were found in this plot: Campylospermum amplectens, Placodiscus boya and Trichoscypha cavalliensis. Thus, the preservation of this forest is more than necessary.展开更多
Background： Tropical dry forests cover less than 13 % of the world＇s tropical forests and their area and biodiversity are declining. In southern Africa, the major threat is increasing population pressure, while drou...Background： Tropical dry forests cover less than 13 % of the world＇s tropical forests and their area and biodiversity are declining. In southern Africa, the major threat is increasing population pressure, while drought caused by climate change is a potential threat in the drier transition zones to shrub land. Monitoring climate change impacts in these transition zones is difficult as there is inadequate information on forest composition to allow disentanglement from other environmental drivers. Methods： This study combined historical and modern forest inventories covering an area of 21,000 km2 in a transition zone in Namibia and Angola to distinguish late succession tree communities, to understand their dependence on site factors, and to detect trends in the forest composition over the last 40 years. Results： The woodlands were dominated by six tree species that represented 84 % of the total basal area and can be referred to as Bdikioea - Pterocarpus woodlands. A boosted regression tree analysis revealed that late succession tree communities are primarily determined by climate and topography. The Schinziophyton rautanenfi and Baikiaea plurijuga communities are common on slightly inclined dune or valley slopes and had the highest basal area （5.5 - 6.2 m^2 ha＆-1）. The Burkea africana - Guibourtia coleosperma and Pterocarpus angolensis - Diafium englerianum communities are typical for the sandy plateaux and have a higher proportion of smaller stems caused by a higher fire frequency. A decrease in overall basal area or a trend of increasing domination by the more drought and cold resilient B. africana community was not confirmed by the historical data, but there were significant decreases in basal area for Ochna pulchra and the valuable fruit tree D. englerianum. Conclusions： The slope communities are more sheltered from fire, frost and drought but are more susceptible to human expansion. The community with the important timber tree P. angolensis can best withstand high fire frequency but shows signs of a higher vulnerability to climate change. Conservation and climate adaptation strategies should include protection of the slope communities through refuges. Follow-up studies are needed on short term dynamics, especially near the edges of the transition zone towards shrub land.展开更多
基金supported by the Nature Science Foundation of China(No.30800859 and No.30871948)the Key Projects in the National Science and Technology Pillar Program during the Eleventh Five-year Plan Period(2008BAD94B09)
文摘In order to better understand shrimp allergen,some basic characters of the major allergen of greasy-back shrimp(Metapenaeus ensis)were investigated.The major allergen was extracted and separated,and its peptide mass fingerprint(PMF)wasanalyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDI-TOF-MS).After screening inthe NCBI database with Mascot searching engine,the results indicated that the major allergen of greasy-back shirmp was muscletropomyosin.Database matching search showed that the top protein matched,i.e.the tropomyosin from giant tiger prawn(Penaeusmonodon),had a Mowse value of 268.In addition,there were 27 queries matched with the allergen in greasy-back shirmp with anamino acid sequence coverage value of 65%.The matching scores and the sequence coverage values were also high with tropomy-osins of other invertebrates,including Tyrophagus putrescentiae and Lepisma saccharina.These results indicated that the allergen ofMetapenaeus ensis had high homology with other crustacean allergens,and provided molecular explanations for the highcross-reactivity of the major allergens between crustaceans and some other invertebrates.
文摘A novel hasubanan alkaloid has been isolated along with the known aknadinine from the fresh roots of Stephania sutchenensis.Its structure has been established as 1—nitroaknadinine from detailed spectral studies and confirmed by chemical correlation with aknadinine.The novel alkaloid is the first nitro-hasubanan and also the first example of naturally occurring nitro—alkaloids.
文摘This study reports the variation of residual strains within the posterior ventral area of the Ensis siliqua mollusc shell, as determined using glancing incidence synchrotron X-ray diffraction. The outer layer of this structure exhibits a tensile strain, in contrast to a compressive strain observed within the inner layer. Fluctuations in unit cell parameters for the inner layer have been determined, showing that the microscopic prismatic layer of the structure exhibits a compressive strain orientated parallel to the surface of the shell. This is thought to enhance the crack deflection properties of this layer, and aid in resisting catastrophic failure. Further analysis of residual strains has been performed using the same method, throughout several stages of compressive testing of the anterior dorsal region of the shell. This identified no variation in residual strains at various levels of loading, and it is therefore proposed that load may be transferred via the organic matrix of mollusc shell structures. A Raman spectroscopic investigation, comparing whole and powdered shell with non-biogenic aragonite, has shown that residual strains are also present in this analagous material which is devoid of organic content. This indicates that the observed strain is not entirely due to the organic matrix.
基金Supported by the Key Foundation Research Program of Fujian Province (1998-2002).
文摘By using immunocytochemistry method of Strept Avidin-Biotin-Complex, four kinds of antisera raised against rabbits were applied to observe the immunoreactive neurons and neuropils of sero-tonin (5-HT), neuropeptide Y (NPY), substance P (SP) and β-Endorphin (β-Ep) in optic ganglia and brain of Metapenaeus ensis. The results showed that, the 5-HT-immunoreactive cells were located in all the four neuropils of optic ganglia. Immunoreactivity of 5-HT was detected in anterior medial protocerebrum neuropils (AMPN), and the inner and outer lateral beside olfactory lobe (OL) of deutocerebrum. The presence of NPY-immunoreactive cells was found in all the four neuropils of the optic ganglia. NPY-immunoreactivity occurred in the anterior median cell cluster, lateral cell cluster of protocerebrum, and cell cluster beside OL and AMPN. SP-immunoreactivity was found in medulla terminalis (MT) of optic ganglia, and lateral cell cluster of protocerebrum and posterior lateral cell cluster of tritocerebrum. β-Ep-immunoreactive cells were in MT only. In conclusion, these specific distribution patterns of the four immunoreactive substances can be used as morphological clues for understanding their different neuro-physiological functions.
文摘The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This is the case of Aubregrinia taïensis (Aubrév. & Pellegr.) Heine, a critically endangered Sapotaceae species, endemic to Côte d’Ivoire and Ghana. After 3 years of investigation in and around the Tai National Park (TNP) in the West of Côte d’Ivoire, only one individual of this species was located and no sexual reproductive organs (fruits, seeds) were observed. Woody plant species around this individual were inventoried in order to know the species that can co-occur with Aubregrinia taïensis. For that a plot of 30 m of diameter was established around the individual and all of the woody species of this circle were inventoried. Then, the taxonomic diversity, the chorology of the species, the conservation status and their life-form were recorded. A total of 130 woody plant species belonging to 51 families were collected in the site. The most represented families are Euphorbiaceae (12 spp.), Rubiaceae (10 spp.), Annonaceae (7 spp.), Fabaceae, Moraceae, Malvaceae (6 spp. each) while the most represented genera are Diospyros L. (4 spp.), Cola Schott & Endl. and Vitex L. (3 spp.). Species from the Guineo-Congolese Region (GC) are the most abundant (72%). They are followed by West African endemic species (GCW, 19%). Microphanerophytes (mp) are the most abundant and represent more than 40% of the species. Three vulnerable species were found in this plot: Campylospermum amplectens, Placodiscus boya and Trichoscypha cavalliensis. Thus, the preservation of this forest is more than necessary.
基金support of The Future Okavango(TFO)and the SASSCAL projects which were funded by the German Federal Ministry of Education and Research under promotion numbers 01 LL 0912 A and 01 LG1201 M respectivelysupport by the KLIMOS ACROPOLIS research platform(Belgian Development Aid through VLIR/ARES)
文摘Background： Tropical dry forests cover less than 13 % of the world＇s tropical forests and their area and biodiversity are declining. In southern Africa, the major threat is increasing population pressure, while drought caused by climate change is a potential threat in the drier transition zones to shrub land. Monitoring climate change impacts in these transition zones is difficult as there is inadequate information on forest composition to allow disentanglement from other environmental drivers. Methods： This study combined historical and modern forest inventories covering an area of 21,000 km2 in a transition zone in Namibia and Angola to distinguish late succession tree communities, to understand their dependence on site factors, and to detect trends in the forest composition over the last 40 years. Results： The woodlands were dominated by six tree species that represented 84 % of the total basal area and can be referred to as Bdikioea - Pterocarpus woodlands. A boosted regression tree analysis revealed that late succession tree communities are primarily determined by climate and topography. The Schinziophyton rautanenfi and Baikiaea plurijuga communities are common on slightly inclined dune or valley slopes and had the highest basal area （5.5 - 6.2 m^2 ha＆-1）. The Burkea africana - Guibourtia coleosperma and Pterocarpus angolensis - Diafium englerianum communities are typical for the sandy plateaux and have a higher proportion of smaller stems caused by a higher fire frequency. A decrease in overall basal area or a trend of increasing domination by the more drought and cold resilient B. africana community was not confirmed by the historical data, but there were significant decreases in basal area for Ochna pulchra and the valuable fruit tree D. englerianum. Conclusions： The slope communities are more sheltered from fire, frost and drought but are more susceptible to human expansion. The community with the important timber tree P. angolensis can best withstand high fire frequency but shows signs of a higher vulnerability to climate change. Conservation and climate adaptation strategies should include protection of the slope communities through refuges. Follow-up studies are needed on short term dynamics, especially near the edges of the transition zone towards shrub land.
