Schistosomiasis is a parasitic disease mostly found in areas along the Changjiang River of China. The disease is spread solely through an intermediary named oncomelania, so its spread of schistosomiasis can be control...Schistosomiasis is a parasitic disease mostly found in areas along the Changjiang River of China. The disease is spread solely through an intermediary named oncomelania, so its spread of schistosomiasis can be controlled by properly designing water intakes which prevent oncomelania from entering farming land or residential areas. This paper reports a successful design process and a new oncomelania free intake device. The design of the new intake is based on a sound research program in which extensive experimental studies were carried out to gain knowledge of oncomelania eco hydraulic behavior and detailed flow field information through CFD simulation.展开更多
Ghrelin was isolated as an endogenous ligand for the GH secretagogue receptor from the rat stomach. Although physiological effects of ghrelin have been revealed by numerous studies, the regulation of stomach ghrelin r...Ghrelin was isolated as an endogenous ligand for the GH secretagogue receptor from the rat stomach. Although physiological effects of ghrelin have been revealed by numerous studies, the regulation of stomach ghrelin remains obscure, and the factor that directly regulates ghrelin expression and production has not been identified. Here, we show some data regarding the characteristic features of ghrelin cells and the regulation of stomach ghrelin. In the gastrointestinal tract, ghrelin cells were identified as opened- and closed-type cells, and it was found that the number of ghrelin cells decreased from the stomach to the colon. The postnatal change in number of ghrelin cells in the stomach showed a sexually dimorphic pattern, indicating a role of estrogen in the regulation of stomach ghrelin. In vitro studies revealed that estrogen stimulated both ghrelin expression and production and that treatment with formestane, an aromatase (estrogen synthetase) inhibitor, decreased ghrelin expression level. On the other hand, leptin was found to inhibit both basal and estrogen-stimulated ghrelin expression. Moreover, both aromatase mRNA- expressing cells and leptin cells were found to be located close to ghrelin cells in the gastric mucosa. Furthermore, we found an inverse relationship between gastric ghrelin and leptin levels in a fasting state, and we revealed relative changes in expression of gastric ghrelin, estrogen and leptin in the postnatal rats. We propose that gastric estrogen and leptin directly regulate stomach ghrelin and that the balance control through gastric estrogen and leptin contributes to the altered ghrelin expression level in some physiological states.展开更多
This study describes the bio-ecology of local Anopheles vectors, their abundance, type and vectoral competence in three communities around Kumasi Metropolis. The study sites were selected based on bio-ecologic zones ...This study describes the bio-ecology of local Anopheles vectors, their abundance, type and vectoral competence in three communities around Kumasi Metropolis. The study sites were selected based on bio-ecologic zones (urban, peri-urban and rural) which influence habitat and behavior. Pyrethrum spray catch was used in the collection of indoor resting mosquitoes from bedrooms of study communities (June-August 2008). The identification of mosquitoes was based on morphological keys earlier described. The blood meal taken and the stage of digestion and egg development were also observed. A total of 293 mosquitoes were collected and 50.5% were A. gambiae s.I. Of the three bio-ecologic zones: urban, 53.4% were A. gambiae s.l, 27.2% Culex and 19.4% Mansonia; peri-urban, 58% A. gambiae s. 1 and 42% Culex pipien s. 1 and rural, 40.2% A. gambiae s. 1, and 58.8% Culex sp respectively. About 96.6% of all mosquitoes collected had taken blood meals, with 50% of these being Anopheles gambiae s.I. Our findings indicate that urban rather exhibits rural characteristics and can best be described as "urban poor". However, more data need to be collected to ascertain this. The anopheline mosquitoes in the study communities are highly endophillic and anthropophagic and thus have high vectoral competence. The authors recommend frequent mosquito surveillance to avert malaria epidemic.展开更多
Black band disease (BBD), characterized by the Cyanobacterial dominated pathogenic consortium, is thought to play a key role in the global decline of the coral reef ecosystems. The present paper originally documents...Black band disease (BBD), characterized by the Cyanobacterial dominated pathogenic consortium, is thought to play a key role in the global decline of the coral reef ecosystems. The present paper originally documents a case of BBD from Yongxing Island (Xisha Islands, South China Sea), and further probes the reasons of this abnormal phenomenon. Prior to 2007, corals at northern reef-flat of Yongxing Isand were in healthy growth. Catastrophic coral mortality occurred between 2007 and 2008. The 16S rRNA gene sequencing and PCR amplification, with universally conserved primers, were applied to detect the conta- gious bacterial community of the microbial mat. The results demonstrated that six bacterial divisions constituted the clone libraries derived from the BBD mat, and that Cyanobacteria are the most diversely represented group that inhabit BBD bacteri- al mats, despite the fact that species in five others divisions (a-Proteobacteria, y-Proteobacteria, Bacteroidetes, Verrucomi- crobia and Actinobacteria) are also consistently diverse within the BBD mats of diseased coral. Other factors such as coral bleaching, typhoons, ocean acidification and crown-of-thorns starfish outbreaks, are not primarily responsible for the coral mortality within such a short time interval. The disaster expansion of BBD associated with Cyanobacterial blooms is a more likely mechanism impacting these coral reefs. Excessive human activity enhances the eutrophication of the marine water of the reefal region and may result in occurrence of the BBD.展开更多
文摘Schistosomiasis is a parasitic disease mostly found in areas along the Changjiang River of China. The disease is spread solely through an intermediary named oncomelania, so its spread of schistosomiasis can be controlled by properly designing water intakes which prevent oncomelania from entering farming land or residential areas. This paper reports a successful design process and a new oncomelania free intake device. The design of the new intake is based on a sound research program in which extensive experimental studies were carried out to gain knowledge of oncomelania eco hydraulic behavior and detailed flow field information through CFD simulation.
基金Supported by (in part) Grants for research fellowships from the Japan Society for the Promotion of Science for Young Scientists by the Program for Promotion of Fundamental Studies in Health Sciences of the National Institute of Biomedical Innovation (NIBIO)
文摘Ghrelin was isolated as an endogenous ligand for the GH secretagogue receptor from the rat stomach. Although physiological effects of ghrelin have been revealed by numerous studies, the regulation of stomach ghrelin remains obscure, and the factor that directly regulates ghrelin expression and production has not been identified. Here, we show some data regarding the characteristic features of ghrelin cells and the regulation of stomach ghrelin. In the gastrointestinal tract, ghrelin cells were identified as opened- and closed-type cells, and it was found that the number of ghrelin cells decreased from the stomach to the colon. The postnatal change in number of ghrelin cells in the stomach showed a sexually dimorphic pattern, indicating a role of estrogen in the regulation of stomach ghrelin. In vitro studies revealed that estrogen stimulated both ghrelin expression and production and that treatment with formestane, an aromatase (estrogen synthetase) inhibitor, decreased ghrelin expression level. On the other hand, leptin was found to inhibit both basal and estrogen-stimulated ghrelin expression. Moreover, both aromatase mRNA- expressing cells and leptin cells were found to be located close to ghrelin cells in the gastric mucosa. Furthermore, we found an inverse relationship between gastric ghrelin and leptin levels in a fasting state, and we revealed relative changes in expression of gastric ghrelin, estrogen and leptin in the postnatal rats. We propose that gastric estrogen and leptin directly regulate stomach ghrelin and that the balance control through gastric estrogen and leptin contributes to the altered ghrelin expression level in some physiological states.
文摘This study describes the bio-ecology of local Anopheles vectors, their abundance, type and vectoral competence in three communities around Kumasi Metropolis. The study sites were selected based on bio-ecologic zones (urban, peri-urban and rural) which influence habitat and behavior. Pyrethrum spray catch was used in the collection of indoor resting mosquitoes from bedrooms of study communities (June-August 2008). The identification of mosquitoes was based on morphological keys earlier described. The blood meal taken and the stage of digestion and egg development were also observed. A total of 293 mosquitoes were collected and 50.5% were A. gambiae s.I. Of the three bio-ecologic zones: urban, 53.4% were A. gambiae s.l, 27.2% Culex and 19.4% Mansonia; peri-urban, 58% A. gambiae s. 1 and 42% Culex pipien s. 1 and rural, 40.2% A. gambiae s. 1, and 58.8% Culex sp respectively. About 96.6% of all mosquitoes collected had taken blood meals, with 50% of these being Anopheles gambiae s.I. Our findings indicate that urban rather exhibits rural characteristics and can best be described as "urban poor". However, more data need to be collected to ascertain this. The anopheline mosquitoes in the study communities are highly endophillic and anthropophagic and thus have high vectoral competence. The authors recommend frequent mosquito surveillance to avert malaria epidemic.
基金supported by National Natural Science Foundation of China(Grant Nos.40976030&41006029)Project of International Cooperation and Exchanges NSFC(Grant No.41210104029)Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.SQ201114)
文摘Black band disease (BBD), characterized by the Cyanobacterial dominated pathogenic consortium, is thought to play a key role in the global decline of the coral reef ecosystems. The present paper originally documents a case of BBD from Yongxing Island (Xisha Islands, South China Sea), and further probes the reasons of this abnormal phenomenon. Prior to 2007, corals at northern reef-flat of Yongxing Isand were in healthy growth. Catastrophic coral mortality occurred between 2007 and 2008. The 16S rRNA gene sequencing and PCR amplification, with universally conserved primers, were applied to detect the conta- gious bacterial community of the microbial mat. The results demonstrated that six bacterial divisions constituted the clone libraries derived from the BBD mat, and that Cyanobacteria are the most diversely represented group that inhabit BBD bacteri- al mats, despite the fact that species in five others divisions (a-Proteobacteria, y-Proteobacteria, Bacteroidetes, Verrucomi- crobia and Actinobacteria) are also consistently diverse within the BBD mats of diseased coral. Other factors such as coral bleaching, typhoons, ocean acidification and crown-of-thorns starfish outbreaks, are not primarily responsible for the coral mortality within such a short time interval. The disaster expansion of BBD associated with Cyanobacterial blooms is a more likely mechanism impacting these coral reefs. Excessive human activity enhances the eutrophication of the marine water of the reefal region and may result in occurrence of the BBD.