When pine trees are invaded by pine wilt diseases, the severely infected pine trees will die and fall down, or they will be removed when found to be damaged by the disease. It gives rise to the invasion of other speci...When pine trees are invaded by pine wilt diseases, the severely infected pine trees will die and fall down, or they will be removed when found to be damaged by the disease. It gives rise to the invasion of other species in these empty niches originally oc- cupied by pine trees, i.e., competing surrounding trees or understory shrubs will invade the empty niches during the following years. As a result, the spatial distribution and pattern of the main tree species in a pine forest will change, and a niche variety in the main population will occur. In the end, the direction of the succession and restoration of the pine forest ecosystem will be affected. In our study, a Pinus massoniana forest with the dominant shrub, Pleioblastus amarus, was invaded by pine wood nematode and was clear cut. Selecting this community as our research object, we studied the effect of the invasion of the pine wood nematode on the growth of the dominant shrub, P. amarus, in this Pinus massoniana forest. Our results show that, after the attacked pine trees were removed, the niche was occupied by Pleioblastus amarus and other shrubs, which benefited the growth ofP. amarus to its climax. Growth of P. amarus at the climax stage was greater compared with the unhealthy pine forest and the control group.展开更多
Objective:To evaluate the antiplasmodial activity of Phyllanthus(P.)amarus crude ethanol leaf extract and its effects on semen quality in male BALB/c mice.Methods:A total of 36 adult mice were divided into six groups,...Objective:To evaluate the antiplasmodial activity of Phyllanthus(P.)amarus crude ethanol leaf extract and its effects on semen quality in male BALB/c mice.Methods:A total of 36 adult mice were divided into six groups,with 6 mice each.Five groups were infected with Plasmodium(P.)berghei,and one group was left uninfeceted.Of the five infected groups,one group was left untreated,three groups were treated with varying doses(100,250 and 400 mg/kg)of P.amarus crude ethanol leaf extract orally for 4 days,and another group was treated with standard drug,artemether and lumefantrine(Lonart®DS).Antiplasmodial activity,seminal quality,some biochemical indices(neutral毩-glucosidase,fructose,and citric acid)in seminal plasma and seminal antioxidant markers(catalase,glutathione peroxidase,reduced glutathione,malondialdehyde,total antioxidant capacity,and acid phosphates)were determined.The mice were euthanized 3 days post treatment and semen was collected from the caudal epididymis and processed for analysis using documented methods and procedures.Results:Malarial infection led to oxidative stress,causing a significant decline in seminal quality(P<0.05).However,treatment with P.amarus crude ethanol leaf extract alleviated oxidative stress and significantly improved seminal quality.The improvement was dose-dependent and compared well with the standard drug,artemether and lumefantrine(Lonart®DS)treatment.Conclusions:The ethanol leaf extracts of P.amarus alleviate male reproductive capacity during malaria infection in murine model by enhancing antioxidant activities.展开更多
Objective:To investigate the antiplasmodial activity of the extracts of Phyllanthus amarus(P. amarus) on Plasmodium yoelii(P.yoelii)(a resistant malaria parasite strain used in animal stuthes) infection in mice.Method...Objective:To investigate the antiplasmodial activity of the extracts of Phyllanthus amarus(P. amarus) on Plasmodium yoelii(P.yoelii)(a resistant malaria parasite strain used in animal stuthes) infection in mice.Methods:The aqueous and ethanol extracts of the whole plant of Phyllanthus amarus was administered to Swiss albino mice at doses of 200 mg/kg/day,400 mg/ kg/day,800 mg/kg/day and 1 600 mg/kg/day and the prophylactic and chemotherapeutic effect of the extracts against P.yoelii infection in mice was investigated and compared with those of standard antimalaria drugs used in the treatment of malaria parasite infection.Acute toxicity test was carried out in mice to determine the safety of the plant extract when administered orally. Results:The results showed that the extracts demonstrated a dose-dependent prophylactic and chemotherapeutic activity with the aqueous extracts showing slightly higher effect than the ethanol extract.The antiplasmodial effects of the extracts were comparable to the standard prophylactic and chemotherapeutic drugs used in chloroquine resistant Plasmodium infection although the activity depended on the dose of the extract administered.The extracts showed prophylactic effect by significantly delaying the onset of infection with the suppression of 79% at a dose of 1 600 mg/kg/day.Conclusions:The results obtained indicate that the extracts of the whole plant of P.amarus possess repository and chemotherapeutic effects against resistant strains of P.yoelii in Swiss albino mice.The findings justify the use of the extract of P.amarus in traditional medicine practice,for the treatment of malaria infections.展开更多
Objective:To screen phytochemicals in ethanolic leaf extracts of Phyllanthus amarus collected from three different geographical zones in Nigeria and evaluate their effects on larva and adult of Anopheles gambiae.Metho...Objective:To screen phytochemicals in ethanolic leaf extracts of Phyllanthus amarus collected from three different geographical zones in Nigeria and evaluate their effects on larva and adult of Anopheles gambiae.Methods:The sample extracts of Phyllanthus amarus prepared with ethanol solvent were tested against Anopheles gambiae at two important developmental stages of its life cycle using slightly modified WHO protocols.Results:Alkaloids,saponins,tannins,flavonoids,glycosides,phenols,and terpenes were detected in each extract.Among these samples,the extract from northwest exhibited the highest larvicidal activity(LC50=263.02 ppm),followed by southeast and southwest extracts(LC50=288.40 and 295.12 ppm,respectively after 48 h),while the extract from southwest exhibited the highest adulticidal activity(LC50=275.42 ppm),followed by northwest and southeast extract(LC50=301.99 and 316.22 ppm,respectively after 24 h).A 50%larva mortality was almost attained at 600 ppm after 48 h duration of exposure to the northwest extract.Conclusions:The tested samples possess strong larvicidal and adulticidal property against Anopheles gambiae which depends on their chemical composition and localities of collection.Further studies are needed to explore the insecticidal activity against a wider range of mosquito species,and to identify active ingredient(s)of the extract responsible for such activity.展开更多
Objective The antifungal activity of various solvent extracts (such as ether, chloroform, ethyl acetate and ethyl alcohol) of the plant Phyllanthus amarus against dermatophytic fungi Microsporum gypseum was observed....Objective The antifungal activity of various solvent extracts (such as ether, chloroform, ethyl acetate and ethyl alcohol) of the plant Phyllanthus amarus against dermatophytic fungi Microsporum gypseum was observed. Method Antifungal bioassay in terms of reduction in weight, colony diameter and sporulation of the target fungal colony was carried out using Broth Dilution method. Results Root part of the plant, extracted in various organic solvents did not show any noticeable antifungal activity. The percentage inhibition observed in different solvent extracts of aerial part was found as reduction in weight: chloroform [50.3%], ethyl acetate [27.7%] and ethyl alcohol [12.1%], reduction in colony diameter: chloroform [53.4%], ethyl acetate [31.4%] and ethyl alcohol [15.0%] and reduction in sporulation: maximum inhibition in chloroform extract, at test concentration of 4000 ppm at incubation period of 8 days. Conclusion Chloroform fraction of the aerial part of the plant P. amarus shows significant inhibitory effect against dermatophytic fungi M. gypseum and requires chemical characterization for its bioactive principle.展开更多
Objective: To determine the changes in serum levels of inflammatory biomarkers and antioxidant levels among the knee osteoarthritis(OA) patients after treatment with Phyllanthus amarus(PP) by nanoparticle gel phonopho...Objective: To determine the changes in serum levels of inflammatory biomarkers and antioxidant levels among the knee osteoarthritis(OA) patients after treatment with Phyllanthus amarus(PP) by nanoparticle gel phonophoresis. Methods: This study was a randomized, double-blind, placebo-control, parallel-group, clinical trial involving 30 subjects with mild-to-moderate degree of knee OA. The patients were allocated to two groups using a computer-generated random numbers, and received conventional ultrasound therapy(control group, 15 cases) and PP(treatment group, 15 cases) once daily for 10 sessions. The pain was evaluated by visual analogue scale(VAS). Serum levels of tumor necrosis factor-α(TNF-α) were determined by enzyme-linked immunosorbnent assay(ELISA). Nitric oxide(NO) was determined by modified Griess reagent. The antioxidant effects, including superoxide dismutase(SOD) and total antioxidant capacity(TAC), were also measured by ELISA assay. Results: The VAS score was significantly decreased in the treatment group compared with the control group after treatment(P<0.01). The serum concentrations of TNF-α and NO were significantly reduced in the treatment group compared with the control group(P<0.01) after treatment. However, the serum concentrations of SOD and TAC in the treatment group were significantly higher after treatment compared with the control group(P<0.01). Conclusion: PP could alleviate knee pain and significantly reduce systemic antiinflammatory effects in knee OA patients.展开更多
1 It's a sunny afternoon in Juliaca,a city near Lake Titicaca,Peru.Among the thousands of native Quechua people gathering in the town square is a man dressed in black on a black horse.He's dressed in memory of...1 It's a sunny afternoon in Juliaca,a city near Lake Titicaca,Peru.Among the thousands of native Quechua people gathering in the town square is a man dressed in black on a black horse.He's dressed in memory of the country's most respected figure:Túpac AmaruⅡ,a native leader who led a war against the Spanish Empire and became a symbol for the fighting spirits in the Andes.He's also there to rap.From horseback,Cay Sur performs his song about heroes,its hip⁃hop beat pulsing(洋溢)through the crowd.展开更多
As an important component of the global carbon （C） budget, litter decomposition in terrestrial ecosystems is greatly affected by the increasing nitrogen （N） deposition observed globally. We hypothesized that diffe...As an important component of the global carbon （C） budget, litter decomposition in terrestrial ecosystems is greatly affected by the increasing nitrogen （N） deposition observed globally. We hypothesized that different litter fractions derived from a single tree species may respond to N deposition differently depending on the quality of the litter substrate. To test the hypothesis, a two-year field experiment was conducted using the litterbag method in a Pleioblastus amarus plantation in the rainy region of Southwest China. Four N treatment levels were applied： control （no N added）, low-N （50 kg N ha-1 year-1）, medium-N （150 kg N ha-a year-1）, and high-N （300 kg N ha-1 year-l）. We observed different patterns of mass loss for the three P. amarus litter fractions （leaves, sheaths, and twigs） of varying substrate quality in the control plots. There were two decomposition stages with different decay rates （fast rate in early stages and slow rate in the later stages） for leaves and sheaths, while we did not observe a slower phase for the decay of twigs during the 2-year study period. The annual decomposition rate （k） of twigs was significantly lower than that of leaves or sheaths. Addition of N slowed the decomposition of leaves and twigs in the later stages of decomposition by inhibiting the decay of lignin and cellulose, while addition of N did not affect the mass loss of sheaths during the study period. In the decomposition of all three litter fractions, experimental N deposition reduced the net N accumulation in the early stages and also decreased the net N release in the later stages. The results of this study suggest that litter substrate quality may be an important factor affecting litter decomposition in a bamboo ecosystem affected by N deposition.展开更多
Bamboos are one of the fast-growing and multiple use species in the world, and thus bamboo forests/plantations play an important role in C sequestration at regional and global levels. We studied aboveground litterfall...Bamboos are one of the fast-growing and multiple use species in the world, and thus bamboo forests/plantations play an important role in C sequestration at regional and global levels. We studied aboveground litterfall, litter decomposition and nutrient dynamics for two years in two subtropical bamboo ecosystems in Southwest China so as to test the hypothesis that litter quality determine the rate and nutrient dynamics during decomposition of different litter fractions. Mean annual total aboveground litter production ranged from 494 to 434 g m-2 in two bamboo stands （P stand, dominated by Pleioblastus amarus and H stand, hybrid bamboo dominated by Bambusa pervariabilis x Dendrocalamopsis daii）. Bulk （-80%） of litter production was contributed by leaf litter in two stands followed by twigs and sheathes. Different litter fractions represented considerable variations in the rates of mass loss and nutrient release. Variation of the mass remaining after 2 years of decomposition was significantly explained by initial C/N ratio and initial P concentration. Initial concentrations of N, P, Ca, and Mg explained 57.9%, 95.0%, 99.8% and 98.1%, respectively, of the variations of these elements mass remaining after 2 years of decomposition. The patterns of nutrient dynamics and the final amount remaining were mainly determined by their initial litter substrate quality in tl^ese two subtropical bamboo plantations.展开更多
In order to understand the effects of increasing atmospheric nitrogen （N） deposition on the subtropical bamboo ecosystem, a nearly six-year field experiment was conducted in a Pleioblastus amarus plantation in the r...In order to understand the effects of increasing atmospheric nitrogen （N） deposition on the subtropical bamboo ecosystem, a nearly six-year field experiment was conducted in a Pleioblastus amarus plantation in the rainy region of SW China, near the western edge of Sichuan Basin. Four N treatment levels---control （no N added）, low- N （50 kg N ha-1 a-l）, medium-N （150 kg N ha-1 a-l）, and high-N （300 kg N ha-1 a-1）--were applied monthly in the P. amarus plantation starting in November 2007. In June 2012, we collected intact soil cores in the bamboo plantation and conducted a 30-day laboratory incubation experiment. The results showed that the soil N net miner- alization rate was 0.96 4- 0.10 mg N kg-1 day-1, under control treatment. N additions stimulated the soil N net mineralization, and the high-N treatment significantly increased the soil N net mineralization rate compared with the control. Moreover, the soil N net mineralization rate was significantly and positively correlated with the fine root biomass, the soil microbial biomass nitrogen content and the soil initial inorganic N content, respectively,whereas it was negatively correlated with the soil pH value. There were no significant relationships between the soil N net mineralization rate and the soil total nitrogen （TN） content and the soil total organic carbon content and the soil C/N ratio and the soil microbial biomass carbon con- tent, respectively. These results suggest that N additions would improve the mineral N availability in the topsoil of the P. amarus plantation through the effects of N additions on soil chemical and physical characteristics and fine-root biomass.展开更多
Objective:To identify the possible anliplasmodial compounds from Achyranlhes aspera(A. aspera).Acalypha indica(A.indica),Jatropha glandulifera(J.glanduUfera)and Phyllanlhus amarus(P.amarus).Methods:The A.aspera,A.indi...Objective:To identify the possible anliplasmodial compounds from Achyranlhes aspera(A. aspera).Acalypha indica(A.indica),Jatropha glandulifera(J.glanduUfera)and Phyllanlhus amarus(P.amarus).Methods:The A.aspera,A.indica,J.glandulifera and P.ainarus were collected along Palk Strait and the extraction was carried out in ethanol.The filter sterilized extracts(100,50,25,12.5,6.25 and 3.125μg/mL) of leaf,stem,root and flower extracts of A aspera,A. indica,J.glandulifera and P.amarus were tested for anliplasmodial activity against Plasnuxlium falciparum.The potential extracts were also tested for their phytochemical constituents.Results: Of the selected plants species parts,the stem extract of A.indica showed excellent antiplasmodial activity(IC_(50)=43.81μg/mL) followed by stem extract of J.glandulifera(IC_(50)= 49.14μg/mL).The stem extract of A.aspera,leaf and root extracts of A.indka,leaf,root and seed extracts of J. glanduUfera and leaf and stem extracts of P.amarus showed IC_(50),values between 50 and 100 μg/ mL.Statistical analysis revealed that,significant antiplasmodial activity(P<0.0l) was observed between the concentrations and time of exposure.The chemical injury to erythrocytes was also carried out and it showed that there were no morphological changes in erythrocytes by the elhanolic extract of all the tested plant extracts.The in vitro antiplasmodial activity might be due to the presence of alkaloids,glycosides,flavonoids.phenols,saponins,triterpenoids,proteins, and lannins in the elhanolic extracts of tested plants.Conclusions:The elhanolic stem extracts of P.amarus and J.glandulifera possess lead compounds for the development of antiplasmodial drugs.展开更多
Landfills are contaminated sites that need to be cleaned up to prevent human and environmental exposure to pollutants. This article aims to identify local plants capable of restoring soil polluted by heavy metals. To ...Landfills are contaminated sites that need to be cleaned up to prevent human and environmental exposure to pollutants. This article aims to identify local plants capable of restoring soil polluted by heavy metals. To this end, plant species at the Bonoua landfill were inventoried. X-ray fluorescence spectrometry was used to determine the heavy metal content of soil and plants from the landfill. The bioconcentration factor (BCF) of metals in plants was evaluated. The Bonoua landfill is covered with 62 plant species, comprising 28 botanical families and 50 genera. The BCF varied from 0.08 (titanium) to 2.27 (strontium) for Phyllanthus amarus;from 0.06 (titanium) to 1.83 (copper) for Alternanthera sessilis and from 0.03 (arsenic) to 2.10 (strontium) for Amaranthus spinosus. Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are strontium-accumulating species (BCF > 1). Similarly, copper BCF values were above 1 for Phyllanthus amarus, and Alternanthera sessilis. These two plant species are therefore copper accumulators. In short, Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are candidate species for phytoremediation of heavy metal-polluted soils, given their BCF > 1.展开更多
基金supported by the State Key Development Program for Basic Research of China ("973" Project) (2009CB119200)the National Project of Science+1 种基金Technology for the 11th Five-Year Plan in China (Grant No. 2006BAD08A15)the "948" Project of State Forestry Administration,P. R. China (2006-4-37)
文摘When pine trees are invaded by pine wilt diseases, the severely infected pine trees will die and fall down, or they will be removed when found to be damaged by the disease. It gives rise to the invasion of other species in these empty niches originally oc- cupied by pine trees, i.e., competing surrounding trees or understory shrubs will invade the empty niches during the following years. As a result, the spatial distribution and pattern of the main tree species in a pine forest will change, and a niche variety in the main population will occur. In the end, the direction of the succession and restoration of the pine forest ecosystem will be affected. In our study, a Pinus massoniana forest with the dominant shrub, Pleioblastus amarus, was invaded by pine wood nematode and was clear cut. Selecting this community as our research object, we studied the effect of the invasion of the pine wood nematode on the growth of the dominant shrub, P. amarus, in this Pinus massoniana forest. Our results show that, after the attacked pine trees were removed, the niche was occupied by Pleioblastus amarus and other shrubs, which benefited the growth ofP. amarus to its climax. Growth of P. amarus at the climax stage was greater compared with the unhealthy pine forest and the control group.
文摘Objective:To evaluate the antiplasmodial activity of Phyllanthus(P.)amarus crude ethanol leaf extract and its effects on semen quality in male BALB/c mice.Methods:A total of 36 adult mice were divided into six groups,with 6 mice each.Five groups were infected with Plasmodium(P.)berghei,and one group was left uninfeceted.Of the five infected groups,one group was left untreated,three groups were treated with varying doses(100,250 and 400 mg/kg)of P.amarus crude ethanol leaf extract orally for 4 days,and another group was treated with standard drug,artemether and lumefantrine(Lonart®DS).Antiplasmodial activity,seminal quality,some biochemical indices(neutral毩-glucosidase,fructose,and citric acid)in seminal plasma and seminal antioxidant markers(catalase,glutathione peroxidase,reduced glutathione,malondialdehyde,total antioxidant capacity,and acid phosphates)were determined.The mice were euthanized 3 days post treatment and semen was collected from the caudal epididymis and processed for analysis using documented methods and procedures.Results:Malarial infection led to oxidative stress,causing a significant decline in seminal quality(P<0.05).However,treatment with P.amarus crude ethanol leaf extract alleviated oxidative stress and significantly improved seminal quality.The improvement was dose-dependent and compared well with the standard drug,artemether and lumefantrine(Lonart®DS)treatment.Conclusions:The ethanol leaf extracts of P.amarus alleviate male reproductive capacity during malaria infection in murine model by enhancing antioxidant activities.
文摘Objective:To investigate the antiplasmodial activity of the extracts of Phyllanthus amarus(P. amarus) on Plasmodium yoelii(P.yoelii)(a resistant malaria parasite strain used in animal stuthes) infection in mice.Methods:The aqueous and ethanol extracts of the whole plant of Phyllanthus amarus was administered to Swiss albino mice at doses of 200 mg/kg/day,400 mg/ kg/day,800 mg/kg/day and 1 600 mg/kg/day and the prophylactic and chemotherapeutic effect of the extracts against P.yoelii infection in mice was investigated and compared with those of standard antimalaria drugs used in the treatment of malaria parasite infection.Acute toxicity test was carried out in mice to determine the safety of the plant extract when administered orally. Results:The results showed that the extracts demonstrated a dose-dependent prophylactic and chemotherapeutic activity with the aqueous extracts showing slightly higher effect than the ethanol extract.The antiplasmodial effects of the extracts were comparable to the standard prophylactic and chemotherapeutic drugs used in chloroquine resistant Plasmodium infection although the activity depended on the dose of the extract administered.The extracts showed prophylactic effect by significantly delaying the onset of infection with the suppression of 79% at a dose of 1 600 mg/kg/day.Conclusions:The results obtained indicate that the extracts of the whole plant of P.amarus possess repository and chemotherapeutic effects against resistant strains of P.yoelii in Swiss albino mice.The findings justify the use of the extract of P.amarus in traditional medicine practice,for the treatment of malaria infections.
文摘Objective:To screen phytochemicals in ethanolic leaf extracts of Phyllanthus amarus collected from three different geographical zones in Nigeria and evaluate their effects on larva and adult of Anopheles gambiae.Methods:The sample extracts of Phyllanthus amarus prepared with ethanol solvent were tested against Anopheles gambiae at two important developmental stages of its life cycle using slightly modified WHO protocols.Results:Alkaloids,saponins,tannins,flavonoids,glycosides,phenols,and terpenes were detected in each extract.Among these samples,the extract from northwest exhibited the highest larvicidal activity(LC50=263.02 ppm),followed by southeast and southwest extracts(LC50=288.40 and 295.12 ppm,respectively after 48 h),while the extract from southwest exhibited the highest adulticidal activity(LC50=275.42 ppm),followed by northwest and southeast extract(LC50=301.99 and 316.22 ppm,respectively after 24 h).A 50%larva mortality was almost attained at 600 ppm after 48 h duration of exposure to the northwest extract.Conclusions:The tested samples possess strong larvicidal and adulticidal property against Anopheles gambiae which depends on their chemical composition and localities of collection.Further studies are needed to explore the insecticidal activity against a wider range of mosquito species,and to identify active ingredient(s)of the extract responsible for such activity.
文摘Objective The antifungal activity of various solvent extracts (such as ether, chloroform, ethyl acetate and ethyl alcohol) of the plant Phyllanthus amarus against dermatophytic fungi Microsporum gypseum was observed. Method Antifungal bioassay in terms of reduction in weight, colony diameter and sporulation of the target fungal colony was carried out using Broth Dilution method. Results Root part of the plant, extracted in various organic solvents did not show any noticeable antifungal activity. The percentage inhibition observed in different solvent extracts of aerial part was found as reduction in weight: chloroform [50.3%], ethyl acetate [27.7%] and ethyl alcohol [12.1%], reduction in colony diameter: chloroform [53.4%], ethyl acetate [31.4%] and ethyl alcohol [15.0%] and reduction in sporulation: maximum inhibition in chloroform extract, at test concentration of 4000 ppm at incubation period of 8 days. Conclusion Chloroform fraction of the aerial part of the plant P. amarus shows significant inhibitory effect against dermatophytic fungi M. gypseum and requires chemical characterization for its bioactive principle.
基金Supported by CMU Junior Research Fellowship Programthe Faculty of Associated Medical Sciences,Chiang Mai University,Thailand(No.8/2560)
文摘Objective: To determine the changes in serum levels of inflammatory biomarkers and antioxidant levels among the knee osteoarthritis(OA) patients after treatment with Phyllanthus amarus(PP) by nanoparticle gel phonophoresis. Methods: This study was a randomized, double-blind, placebo-control, parallel-group, clinical trial involving 30 subjects with mild-to-moderate degree of knee OA. The patients were allocated to two groups using a computer-generated random numbers, and received conventional ultrasound therapy(control group, 15 cases) and PP(treatment group, 15 cases) once daily for 10 sessions. The pain was evaluated by visual analogue scale(VAS). Serum levels of tumor necrosis factor-α(TNF-α) were determined by enzyme-linked immunosorbnent assay(ELISA). Nitric oxide(NO) was determined by modified Griess reagent. The antioxidant effects, including superoxide dismutase(SOD) and total antioxidant capacity(TAC), were also measured by ELISA assay. Results: The VAS score was significantly decreased in the treatment group compared with the control group after treatment(P<0.01). The serum concentrations of TNF-α and NO were significantly reduced in the treatment group compared with the control group(P<0.01) after treatment. However, the serum concentrations of SOD and TAC in the treatment group were significantly higher after treatment compared with the control group(P<0.01). Conclusion: PP could alleviate knee pain and significantly reduce systemic antiinflammatory effects in knee OA patients.
文摘1 It's a sunny afternoon in Juliaca,a city near Lake Titicaca,Peru.Among the thousands of native Quechua people gathering in the town square is a man dressed in black on a black horse.He's dressed in memory of the country's most respected figure:Túpac AmaruⅡ,a native leader who led a war against the Spanish Empire and became a symbol for the fighting spirits in the Andes.He's also there to rap.From horseback,Cay Sur performs his song about heroes,its hip⁃hop beat pulsing(洋溢)through the crowd.
基金Supported by the National Key Technologies Research and Development Program of China during the 11th Five-Year Plan Period (No. 2006BAC01A11)
文摘As an important component of the global carbon （C） budget, litter decomposition in terrestrial ecosystems is greatly affected by the increasing nitrogen （N） deposition observed globally. We hypothesized that different litter fractions derived from a single tree species may respond to N deposition differently depending on the quality of the litter substrate. To test the hypothesis, a two-year field experiment was conducted using the litterbag method in a Pleioblastus amarus plantation in the rainy region of Southwest China. Four N treatment levels were applied： control （no N added）, low-N （50 kg N ha-1 year-1）, medium-N （150 kg N ha-a year-1）, and high-N （300 kg N ha-1 year-l）. We observed different patterns of mass loss for the three P. amarus litter fractions （leaves, sheaths, and twigs） of varying substrate quality in the control plots. There were two decomposition stages with different decay rates （fast rate in early stages and slow rate in the later stages） for leaves and sheaths, while we did not observe a slower phase for the decay of twigs during the 2-year study period. The annual decomposition rate （k） of twigs was significantly lower than that of leaves or sheaths. Addition of N slowed the decomposition of leaves and twigs in the later stages of decomposition by inhibiting the decay of lignin and cellulose, while addition of N did not affect the mass loss of sheaths during the study period. In the decomposition of all three litter fractions, experimental N deposition reduced the net N accumulation in the early stages and also decreased the net N release in the later stages. The results of this study suggest that litter substrate quality may be an important factor affecting litter decomposition in a bamboo ecosystem affected by N deposition.
基金Supported by the National Natural Science Foundation,China(No.31300522)the Specialized Research Fund for the Doctoral Program of Higher Education,China(No.20125103120018)+1 种基金the Scientific Research Fund of Sichuan Provincial Education Department,China(No.12ZA118)the National Key Technology R&D Program,China(No.2011BAC09B05)
文摘Bamboos are one of the fast-growing and multiple use species in the world, and thus bamboo forests/plantations play an important role in C sequestration at regional and global levels. We studied aboveground litterfall, litter decomposition and nutrient dynamics for two years in two subtropical bamboo ecosystems in Southwest China so as to test the hypothesis that litter quality determine the rate and nutrient dynamics during decomposition of different litter fractions. Mean annual total aboveground litter production ranged from 494 to 434 g m-2 in two bamboo stands （P stand, dominated by Pleioblastus amarus and H stand, hybrid bamboo dominated by Bambusa pervariabilis x Dendrocalamopsis daii）. Bulk （-80%） of litter production was contributed by leaf litter in two stands followed by twigs and sheathes. Different litter fractions represented considerable variations in the rates of mass loss and nutrient release. Variation of the mass remaining after 2 years of decomposition was significantly explained by initial C/N ratio and initial P concentration. Initial concentrations of N, P, Ca, and Mg explained 57.9%, 95.0%, 99.8% and 98.1%, respectively, of the variations of these elements mass remaining after 2 years of decomposition. The patterns of nutrient dynamics and the final amount remaining were mainly determined by their initial litter substrate quality in tl^ese two subtropical bamboo plantations.
基金supported by the National Natural Science Foundation of China(No.31300522)Specialized Research Fund for the Doctoral Program of Higher Education of China(No.20125103120018)
文摘In order to understand the effects of increasing atmospheric nitrogen （N） deposition on the subtropical bamboo ecosystem, a nearly six-year field experiment was conducted in a Pleioblastus amarus plantation in the rainy region of SW China, near the western edge of Sichuan Basin. Four N treatment levels---control （no N added）, low- N （50 kg N ha-1 a-l）, medium-N （150 kg N ha-1 a-l）, and high-N （300 kg N ha-1 a-1）--were applied monthly in the P. amarus plantation starting in November 2007. In June 2012, we collected intact soil cores in the bamboo plantation and conducted a 30-day laboratory incubation experiment. The results showed that the soil N net miner- alization rate was 0.96 4- 0.10 mg N kg-1 day-1, under control treatment. N additions stimulated the soil N net mineralization, and the high-N treatment significantly increased the soil N net mineralization rate compared with the control. Moreover, the soil N net mineralization rate was significantly and positively correlated with the fine root biomass, the soil microbial biomass nitrogen content and the soil initial inorganic N content, respectively,whereas it was negatively correlated with the soil pH value. There were no significant relationships between the soil N net mineralization rate and the soil total nitrogen （TN） content and the soil total organic carbon content and the soil C/N ratio and the soil microbial biomass carbon con- tent, respectively. These results suggest that N additions would improve the mineral N availability in the topsoil of the P. amarus plantation through the effects of N additions on soil chemical and physical characteristics and fine-root biomass.
基金Supported by Indian Council of Medical Research,New Delhi(No.59/6/2002/BMS/TRM)
文摘Objective:To identify the possible anliplasmodial compounds from Achyranlhes aspera(A. aspera).Acalypha indica(A.indica),Jatropha glandulifera(J.glanduUfera)and Phyllanlhus amarus(P.amarus).Methods:The A.aspera,A.indica,J.glandulifera and P.ainarus were collected along Palk Strait and the extraction was carried out in ethanol.The filter sterilized extracts(100,50,25,12.5,6.25 and 3.125μg/mL) of leaf,stem,root and flower extracts of A aspera,A. indica,J.glandulifera and P.amarus were tested for anliplasmodial activity against Plasnuxlium falciparum.The potential extracts were also tested for their phytochemical constituents.Results: Of the selected plants species parts,the stem extract of A.indica showed excellent antiplasmodial activity(IC_(50)=43.81μg/mL) followed by stem extract of J.glandulifera(IC_(50)= 49.14μg/mL).The stem extract of A.aspera,leaf and root extracts of A.indka,leaf,root and seed extracts of J. glanduUfera and leaf and stem extracts of P.amarus showed IC_(50),values between 50 and 100 μg/ mL.Statistical analysis revealed that,significant antiplasmodial activity(P<0.0l) was observed between the concentrations and time of exposure.The chemical injury to erythrocytes was also carried out and it showed that there were no morphological changes in erythrocytes by the elhanolic extract of all the tested plant extracts.The in vitro antiplasmodial activity might be due to the presence of alkaloids,glycosides,flavonoids.phenols,saponins,triterpenoids,proteins, and lannins in the elhanolic extracts of tested plants.Conclusions:The elhanolic stem extracts of P.amarus and J.glandulifera possess lead compounds for the development of antiplasmodial drugs.
文摘Landfills are contaminated sites that need to be cleaned up to prevent human and environmental exposure to pollutants. This article aims to identify local plants capable of restoring soil polluted by heavy metals. To this end, plant species at the Bonoua landfill were inventoried. X-ray fluorescence spectrometry was used to determine the heavy metal content of soil and plants from the landfill. The bioconcentration factor (BCF) of metals in plants was evaluated. The Bonoua landfill is covered with 62 plant species, comprising 28 botanical families and 50 genera. The BCF varied from 0.08 (titanium) to 2.27 (strontium) for Phyllanthus amarus;from 0.06 (titanium) to 1.83 (copper) for Alternanthera sessilis and from 0.03 (arsenic) to 2.10 (strontium) for Amaranthus spinosus. Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are strontium-accumulating species (BCF > 1). Similarly, copper BCF values were above 1 for Phyllanthus amarus, and Alternanthera sessilis. These two plant species are therefore copper accumulators. In short, Phyllanthus amarus, Alternanthera sessilis, and Amaranthus spinosus are candidate species for phytoremediation of heavy metal-polluted soils, given their BCF > 1.
