The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using tradition...The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests.展开更多
Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.al...Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.albopictus,and malaria,a parasitic disease transmitted by Anopheles gambiae,are prevalent in Nigeria and neighbouring countries,but their burden and possible coinfections are poorly understood.In this study,we investigated the antibody seropositivity and endemicity of chikungunya and Zika viruses(ZIKV)in three regions of Nigeria.A cross-sectional serosurvey was conducted on 871 participants.Samples were collected from outpatients by simple random sampling.Analyses of the samples were performed using recomLine Tropical Fever for the presence of antibody serological marker IgG immunoblot with CHIKV VLP(virus like particle),ZIKV NS1 and ZIKV Equad according to manufacturers’instructions and malaria RDT for malaria parasite.There was a significantly higher antibody seropositivity against CHIKV in the central region than in the northern and southern regions(69.5%,291/419),while ZIKV-seropositivity(22.4%,34/152)and CHIKV-ZIKV co-circulating antibody seropositivity(17.8%,27/152)were notably higher in the southern region than in the central and northern regions.This investigation revealed an unexpectedly high antibody seropositivity and concealed endemicity of CHIKV and ZIKV in three Nigerian regions.The seropositivity of detectable antibodies differed among the three geographical locations.展开更多
We are currently faced with the question of how the CoV-2 severity may change in the years ahead.Our analysis of immunological and epidemiological data on endemic human coronaviruses(HCoVs)shows that infection-blockin...We are currently faced with the question of how the CoV-2 severity may change in the years ahead.Our analysis of immunological and epidemiological data on endemic human coronaviruses(HCoVs)shows that infection-blocking immunity wanes rapidly,but disease-reducing immunity is long-lived.Our model,incorporating these components of immunity,recapitulates both the current severity of CoV-2 and the benign nature of HCoVs,suggesting that once the endemic phase is reached and primary exposure is in childhood,CoV-2 may be no more virulent than the common cold.展开更多
Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of ...Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of crucial importance in controlling this disease Methods Different factors mimicking the internal and external environmental conditions of the host, including human and fish bile, bacterial phages and antibiotics were used experimentally to induce variation in EVC EVC variants were isolated from the stool of diarrhea patients and river water in old endemic areas during the winter The variants obtained were tested with gene probe hybridization, DNA restriction enzyme mapping, immunoenzyme staining and animal passaging Results Due to the loss of cell walls, 3 kinds of EVC variants were obtained during induction: the L form variant, with a complete loss of cell walls; the nonagglutinating variants, with the loss of surface O antigen; the phage resistant variants, with the loss of phage receptors Similar variants were found in field isolation This variation was proved to be phenotypic, with no change in genetic material: it was reversible and appeared in a seasonal pattern, which coincided with the endemicity of this disease Passage in animal enhanced this reversion In compensation for the loss of cell walls, cell membranes were greatly thickened, increasing the ability of the variants to survive during the unfavorable winter conditions Conclusions EVC varied in a seasonal pattern, coincident with the endemicity of this disease The compensatory thickening of the cell membranes protects the EVC variants to survive the winter展开更多
[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in t...[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.展开更多
Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on...Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on the endemism of liverworts across 390 regions worldwide.We assess phylogenetic endemism and relative phylogenetic endemism in relation to eleven environmental factors,which represent current and Quaternary climate variations,as well as topographic and environmental heterogeneity.Areas with higher endemism in liverworts tend to have higher temperatures,precipitation,and environmental heterogeneity,but lower temperature seasonality and lesser impacts from Quaternary climate changes.Regions exhibiting notably high endemism are predominantly found in tropical Asia,Madagascar,eastern Australia,and the Andes,while those with notably low endemism are generally in temperate Eurasia and North America,parts of Africa,and eastern South America.Centers of neo-endemism are mainly in southern Africa,whereas centers of paleo-endemism are in southern South America,tropical Asia,and New Zealand.Environment variability is a more significant predictor of phylogenetic endemism than current climate conditions,which are themselves more predictive than variables related to Quaternary climate changes.Nevertheless,these three types of explanatory variables combined explain only about one-third of the variance in phylogenetic endemism.展开更多
Salt stress might be an important factor that decreases the emergence of seedlings and reduces plants'growth,causing their endangered status.However,the effects of salt stress on the germination of the Mediterrane...Salt stress might be an important factor that decreases the emergence of seedlings and reduces plants'growth,causing their endangered status.However,the effects of salt stress on the germination of the Mediterranean species are less concern.Limonium strictissimum(Salzm.)Arrigoni,part of the group related to Limonium articulatum(Loisel.)Kuntze,is a Cyrno-Sardinian endemism,which is included in the International Union for Conservation of Nature(IUCN)Red Lists as Endangered(EN).Fresh seeds of L.strictissimum harvested from the only known population in Sardinia and a population in southeastern Corsica were used with the aims to study the effects of temperature and salinity on the seed germination and to evaluate the ability to recover their germination after exposure to salt stress.In both populations,empty fruits with a lower percentage were observed in Sardinia than in Corsica.The seeds showed a high germination capacity,which was not influenced by temperature and did not even differ between the two populations.Compared with non-saline condition,the presence of salt in the substrate,independently of the concentration tested,inhibited seed germination in both populations,with germination percentages never exceeding 40%.The Sardinian population showed a recovery capacity after exposure to high salt stress,always above 50%regardless of the salt concentration and incubation temperature considered.The seeds previously exposed to 125 mM NaCl at 30℃ had the lowest recovery percentage(56%),while the highest recovery percentage(84%)was recorded at 25℃ with a concentration of 250 mM NaCl.Differently,the Corsican population recorded a higher recovery percentage(54%)in seeds previously exposed to 500 mM NaCl at 20℃,while for the concentration of 125 mM NaCl,the best recovery percentage(11%)was recorded at 30℃.The ability of L.strictissimum to recover germination after salt exposure can be interpreted as an adaptation to the coastal habitats in which it grows.This study provides new insights into the ecophysiology of L.strictissimum seed germination,which could help preserve and implement effective conservation measures for this endangered species with restricted populations.展开更多
Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This stu...Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This study was designed to examine the vegetation structure,update the occurrence of endemic taxa,and investigate the impact of environmental conditions and landform types on plant disruption in the region.The primary objective of this study was to analyze the behavior and distribution of the most common species across major environmental gradients.Between 2022 and 2024,49 stands were randomly collected within the study area characterized by relatively uniform vegetation and physiography and represent as much as possible the four major landform types(terraces,slopes,ridges,and gorges).The selected stands were distributed as follows:terraces(12 stands),slopes(9 stands),ridges(9 stands),and gorges(19 stands).For the analysis of the biological spectrum,a growth-form system with four categories was utilized:trees(T),shrubs(S),perennial herbs(PH),and annual herbs(A).Soil analyses were conducted for composite samples from the 49 stands.For each recorded species,nativity,species diversity measurements,endemism,and IUCN conservation status were depicted.Multivariate analysis techniques were used to assess the classification of the 49 stands in various landforms,and ordination with soil variables were applied using different software.A total of 137 taxa were recorded from Gebel Katrina area belonging to 39 families(1 Pteridaceae,1 Ephedraceae,and 37 Angiospermae),of which 16 were endemics,which indicates the mountain's significance as a biodiversity hotspot.Of these endemic taxa,nine were classified as Endangered(EN)and four as Least Concern(LC),together accounting for over 80%of the endemic flora.The largest angiosperm families with the highest numbers of species included Asteraceae,Lamiaceae,Poaceae,Brassicaceae,Caryophyllaceae and Fabaceae.These six families constituted more than 30%of the recorded flora.Shrubs and perennial herbs were the predominant growth forms,collectively comprising over 70%of the total flora.Native taxa comprised the dominant component of the recorded flora,accounting for 80 species(58.4%of the total).In contrast,non-native taxa were limited to two annual grasses.Analysis of IUCN Red List proportions revealed a predominance of EN taxa,accounting for 52 taxa(37.9%),followed by Least Concern(LC)taxa with 36 taxa(26.3%).Together,these two categories constituted over 60%of the total assessed flora.Hierarchical cluster analysis of a presence/absence data matrix(49 stands×91 species after removal of species with occurrences<5%),using the Sørensen(Bray-Curtis)method,identified eight distinct vegetation clusters.Each cluster is characterized by one or more dominant species,distinguished by their highest percentage of occurrence(f)within their respective group.Apart from soil reaction(pH)and diversity indices(species richness and Shannon’s index),ANOVA test showed high significant differences in most of the measured environmental variables among the obtained cluster groups(A-H).Canonical Correspondence Analysis(CCA)showed direct correlations between the 7 examined environmental variables and plant species composition in Gebel Katrina.The eight cluster groups were separated along axes 1 and 2 of the diagram.The species-environment correlations were high for the three axes explaining 63.0%of the cumulative variance.The stands of groups(E)and(G)were correlated with coarse sand,stands of group(B)were highly correlated with electric conductivity(EC),and stands of group(F)were correlated with elevation.The endemic flora of Gebel Katrina faces multiple anthropogenic and environmental threats.Overgrazing by livestock,excessive harvesting of plants for fuelwood and traditional medicinal uses,and habitat degradation due to land-use changes have led to significant depletion of vegetation cover and biodiversity loss.展开更多
Dengue virus(DENV)is a positive-sense single-stranded RNA virus belonging to the genus Flavivirus within the Flaviviridae family.Four serotypes,DENV 1-4,are distributed globally[1].Hanoi metropolitan city is an endemi...Dengue virus(DENV)is a positive-sense single-stranded RNA virus belonging to the genus Flavivirus within the Flaviviridae family.Four serotypes,DENV 1-4,are distributed globally[1].Hanoi metropolitan city is an endemic hotspot for DENV transmission in Vietnam[2,3].The largest outbreak occurred in 2017,with more than 36000 cases and 7 deaths reported,causing by all four serotypes with the predominance of DENV1,following by DENV2[4,5].During the following dengue season,we collected 390 blood and serum samples from 197 hospitalized patients in a national hospital in Hanoi city,Northern Vietnam to identify the circulating DENV serotypes responsible for the 2018-2019 outbreak.展开更多
Hepatitis A,a vaccine-preventable liver infection caused by the hepatitis A virus,is undergoing significant epidemiological shifts worldwide.Traditionally considered a disease of childhood in endemic regions,improved ...Hepatitis A,a vaccine-preventable liver infection caused by the hepatitis A virus,is undergoing significant epidemiological shifts worldwide.Traditionally considered a disease of childhood in endemic regions,improved sanitation,economic development,and widespread vaccination have led to a decline in incidence,particularly in developed nations.However,this decline has resulted in a growing population of susceptible adults,increasing the risk of severe outbreaks.Additionally,changes in travel patterns,urbanization,and socioeconomic disparities have altered disease distribution,leading to sporadic outbreaks in low-endemicity regions and a rising burden in certain high-risk populations.This review explores the evolving epidemiology of hepatitis A,emphasizing the transition from endemic childhood infections to adult susceptibility.We examine the impact of changing risk factors,including shifting demographics,increased international travel,and regional disparities in vaccination coverage.Furthermore,the review highlights the emergence of new viral strains and their potential implications for disease control.Updated vaccination policies,including targeted immunization strategies and their role in preventing outbreaks,are also discussed.Given these dynamic changes,continued surveillance and public health preparedness tailored to evolving risk groups are crucial for sustained hepatitis A control.By synthesizing recent epidemiological data and policy updates,this review provides insights into the future of hepatitis A prevention and control,offering guidance for clinicians,researchers,and public health professionals.展开更多
Malaria is considered one of the major causes of travel-related morbidity and mortality,especially among non-immune travelers from non-endemic countries to the endemic regions.According to a multicenter study from the...Malaria is considered one of the major causes of travel-related morbidity and mortality,especially among non-immune travelers from non-endemic countries to the endemic regions.According to a multicenter study from the GeoSentinel surveillance network,malaria was the most frequent cause of fever in 21%of returning travelers,followed by dengue,typhoid fever,chikungunya and rickettsiosis[1].Individuals traveling from regions without malaria transmission to areas where it is endemic face a heightened risk of contracting the disease due to their lack of immunity.Despite the official malaria-free status of the Russian Federation since 2010,annual cases of severe Plasmodium(P.)falciparum malaria continue to be reported[2].This underscores the necessity for heightened clinical vigilance and improved preventive strategies especially in non-endemic settings.展开更多
The Andaman Islands,part of the Indo-Burma biodiversity hotspot,holds unique florawith many endemic and threatened species.However,this fragile diversity is under increasing pressure from infrastructure expansion,clim...The Andaman Islands,part of the Indo-Burma biodiversity hotspot,holds unique florawith many endemic and threatened species.However,this fragile diversity is under increasing pressure from infrastructure expansion,climate change and habitat fragmentation.The recently announced Great Nicobar Island Development project by the Government of India,which includes an international transhipment terminal,airport,township and power plant,if implemented,would cause major habitat loss and fragmentation,possibly leading to species extinctions.展开更多
Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracte...Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracted early in life,may lead to chronic liver disease,including cirrhosis and hepatocellular carcinoma.On the basis of the HBV carrier rate,the world can be divided in 3 regions of high,medium and low endemicity.The major concern is about high endemicity countries,where the most common route of infection remains vertical transmission from mother to child.Screening of all pregnant women and passive immunization with human hepatitis B immunoglobulin are not affordable for many developing countries.The infection rate can be reduced by modifying behavior,improving individual education,testing all blood donations,assuring asepsis in clinical practice and screening all pregnant women.However,availability of a safe and efficacious vaccine and adoption of appropriate immunization strategies are the most effective means to prevent HBV infection and its consequences.The unsolved problem for poorest countries,where the number of people currently infected is high,is the cost of the vaccine.A future challenge is to overcome the social and economic hurdles of maintaining and improving a prevention policy worldwide to reduce the global burden of the disease.展开更多
Objective:To investigate resistance and safety of HHPG-19K in treating non-small cell lung cancer patients.Methods:A total of 30 cases were selected and randomly divided into 5 groups:three HHPG-19K groups of differen...Objective:To investigate resistance and safety of HHPG-19K in treating non-small cell lung cancer patients.Methods:A total of 30 cases were selected and randomly divided into 5 groups:three HHPG-19K groups of different dosage(60 μg/kg/day,100 μ g/kg/day,200 μ g/ kg/day),positive control group(Filgrastim,namely G-CSF5 μ g/kg/day) and negative control group.Safety indexes of 5 groups were observed and compared.Results:All patients had adverse event(100%) in three HHPG-19K groups,and increased ALP,ALT and AST were main events.The degree was mild to moderate.There was no significant difference in the incidence of adverse event between dosage groups and positive control group no difference.But the incidence of negative control group was 13%,which was significantly lower than dosage groups and positive control group.Conclusions:Non-small cell lung cancer patients have satisfactory tolerance to HHPG-19K,and have no resistance.Besides,dosage at 100 μ g/kg is the most safe.展开更多
文摘The scientific community faces the challenge of measuring progress toward biodiversity targets and indices have been traditionally used.However,recent inventories in secondary tropical mountain forests using traditional biodiversity indices have yielded results that are indistinct with primary ones.This shows the need to develop complementary indices that goes beyond species count but integrates the distribution and conservation status of the species.This study developed endemicity and conservation importance index for tropical forest that incorporated the distribution and conservation status of the species.These indices were applied to Mt.Natoo,a remnant primary mossy forest in Buguias,Benguet,Philippines,that resulted to endemicity index of 81.07 and conservation importance index of 42.90.Comparing these with secondary forest sites with comparable Shannon-Wiener,Simpson,Evenness and Margalef’s indices,our endemicity and conservation indices clearly differentiates primary forest(our study site)with higher values from secondary forests with much lower values.Thus,we are proposing these indices for a direct but scientifically-informed identification of specific sites for conservation and protection in tropical forests.Additionally,our study documented a total of 168 vascular plant species(79 endemic and 12 locally threatened species)in Mt.Nato-o.Majority are of tropical elements for both generic and species levels with some temperate elements that could be attributed to the site's high elevation and semi-temperate climate.These are important baseline information for conservation plans and monitoring of tropical mossy forests.
文摘Mosquito-borne infections are of global health concern because of their rapid spread and upsurge,which creates a risk for coinfections.chikungunya virus(CHIKV),an arbovirus disease transmitted by Aedes aegypti or A.albopictus,and malaria,a parasitic disease transmitted by Anopheles gambiae,are prevalent in Nigeria and neighbouring countries,but their burden and possible coinfections are poorly understood.In this study,we investigated the antibody seropositivity and endemicity of chikungunya and Zika viruses(ZIKV)in three regions of Nigeria.A cross-sectional serosurvey was conducted on 871 participants.Samples were collected from outpatients by simple random sampling.Analyses of the samples were performed using recomLine Tropical Fever for the presence of antibody serological marker IgG immunoblot with CHIKV VLP(virus like particle),ZIKV NS1 and ZIKV Equad according to manufacturers’instructions and malaria RDT for malaria parasite.There was a significantly higher antibody seropositivity against CHIKV in the central region than in the northern and southern regions(69.5%,291/419),while ZIKV-seropositivity(22.4%,34/152)and CHIKV-ZIKV co-circulating antibody seropositivity(17.8%,27/152)were notably higher in the southern region than in the central and northern regions.This investigation revealed an unexpectedly high antibody seropositivity and concealed endemicity of CHIKV and ZIKV in three Nigerian regions.The seropositivity of detectable antibodies differed among the three geographical locations.
文摘We are currently faced with the question of how the CoV-2 severity may change in the years ahead.Our analysis of immunological and epidemiological data on endemic human coronaviruses(HCoVs)shows that infection-blocking immunity wanes rapidly,but disease-reducing immunity is long-lived.Our model,incorporating these components of immunity,recapitulates both the current severity of CoV-2 and the benign nature of HCoVs,suggesting that once the endemic phase is reached and primary exposure is in childhood,CoV-2 may be no more virulent than the common cold.
文摘Objective Cholera caused by Vibrio cholerae biotype eltor (EVC) is an endemic disease, subsiding in winter and reappearing in spring and summer Investigating the state of EVC during the intermittent time is of crucial importance in controlling this disease Methods Different factors mimicking the internal and external environmental conditions of the host, including human and fish bile, bacterial phages and antibiotics were used experimentally to induce variation in EVC EVC variants were isolated from the stool of diarrhea patients and river water in old endemic areas during the winter The variants obtained were tested with gene probe hybridization, DNA restriction enzyme mapping, immunoenzyme staining and animal passaging Results Due to the loss of cell walls, 3 kinds of EVC variants were obtained during induction: the L form variant, with a complete loss of cell walls; the nonagglutinating variants, with the loss of surface O antigen; the phage resistant variants, with the loss of phage receptors Similar variants were found in field isolation This variation was proved to be phenotypic, with no change in genetic material: it was reversible and appeared in a seasonal pattern, which coincided with the endemicity of this disease Passage in animal enhanced this reversion In compensation for the loss of cell walls, cell membranes were greatly thickened, increasing the ability of the variants to survive during the unfavorable winter conditions Conclusions EVC varied in a seasonal pattern, coincident with the endemicity of this disease The compensatory thickening of the cell membranes protects the EVC variants to survive the winter
文摘[Objective]Implementation of the Ten-Year Fishing Ban policy may alter fish diversity and niche characteristics of dominant species in spawning grounds within the National Nature Reserve for Rare and Endemic Fish in the Upper Yangtze River.This study initiated continuous monitoring of natural spawning habitats from February 2022 to assess these ecological changes.[Methods]Environmental DNA(eDNA)metabarcoding was employed to analyze fish species composition,biodiversity patterns,and niche parameters of dominant species.Water sampling followed the CEN/TS 19461 standard across five monitoring transects(ZT1-ZT5).[Results]The eDNA analysis detected 45 species of fish belonging to 38 genera,13 families,and 3 orders were detected through environmental DNA(eDNA)in this survey,including 10 species endemic to the upper reaches of the Yangtze River,such as Procypris rabaudi and Myxocyprinus asiaticus.The fish community was mainly composed of bottom-dwelling,settling ovum-producing,omnivorous fish.The variation ranges of the Chao1 index,ACE index,Shannon index,and Simpson index are 736~996,719~965,1.58~3.23,and 0.83~0.99,respectively,indicating that fish species in spawning sites are abundant and community distribution uniformity is high.All indexes are highest at ZT1 monitoring points.Cluster analysis showed that,at a certain similarity level,fish community types in spawning sites could be basically divided into two groups:ZT1,ZT3,and ZT5 clustered together,and ZT2 and ZT4 clustered together,indicating similar fish community habitats.There are 9 dominant fish species in typical deep pool habitats in the reserve,with niche widths(Bi)ranging from 1.13 to 3.87.The dominant fish species are broad and medium niche fish,such as Cyprinus carpio and Hemiculter tchangi,with the niche overlap index(Oik)of some dominant fish species reaching more than 0.95.This indicates fierce competition for resources among the fish in this spawning ground.[Conclusion]The Zhutuo spawning ground demonstrates high species richness with homogeneous community structure and intense resource competition.This study establishes an eDNA-based monitoring framework that enhances conventional survey method,providing critical baseline data for adaptive management under the fishing moratorium regime.
文摘Exploring the worldwide patterns of endemism and the processes that lead to the formation of highendemism centers is crucial in biogeography.This study examines the geographic distribution and ecological influences on the endemism of liverworts across 390 regions worldwide.We assess phylogenetic endemism and relative phylogenetic endemism in relation to eleven environmental factors,which represent current and Quaternary climate variations,as well as topographic and environmental heterogeneity.Areas with higher endemism in liverworts tend to have higher temperatures,precipitation,and environmental heterogeneity,but lower temperature seasonality and lesser impacts from Quaternary climate changes.Regions exhibiting notably high endemism are predominantly found in tropical Asia,Madagascar,eastern Australia,and the Andes,while those with notably low endemism are generally in temperate Eurasia and North America,parts of Africa,and eastern South America.Centers of neo-endemism are mainly in southern Africa,whereas centers of paleo-endemism are in southern South America,tropical Asia,and New Zealand.Environment variability is a more significant predictor of phylogenetic endemism than current climate conditions,which are themselves more predictive than variables related to Quaternary climate changes.Nevertheless,these three types of explanatory variables combined explain only about one-third of the variance in phylogenetic endemism.
基金funded by the Life Seedforce(Life20 NAT/IT/001468)。
文摘Salt stress might be an important factor that decreases the emergence of seedlings and reduces plants'growth,causing their endangered status.However,the effects of salt stress on the germination of the Mediterranean species are less concern.Limonium strictissimum(Salzm.)Arrigoni,part of the group related to Limonium articulatum(Loisel.)Kuntze,is a Cyrno-Sardinian endemism,which is included in the International Union for Conservation of Nature(IUCN)Red Lists as Endangered(EN).Fresh seeds of L.strictissimum harvested from the only known population in Sardinia and a population in southeastern Corsica were used with the aims to study the effects of temperature and salinity on the seed germination and to evaluate the ability to recover their germination after exposure to salt stress.In both populations,empty fruits with a lower percentage were observed in Sardinia than in Corsica.The seeds showed a high germination capacity,which was not influenced by temperature and did not even differ between the two populations.Compared with non-saline condition,the presence of salt in the substrate,independently of the concentration tested,inhibited seed germination in both populations,with germination percentages never exceeding 40%.The Sardinian population showed a recovery capacity after exposure to high salt stress,always above 50%regardless of the salt concentration and incubation temperature considered.The seeds previously exposed to 125 mM NaCl at 30℃ had the lowest recovery percentage(56%),while the highest recovery percentage(84%)was recorded at 25℃ with a concentration of 250 mM NaCl.Differently,the Corsican population recorded a higher recovery percentage(54%)in seeds previously exposed to 500 mM NaCl at 20℃,while for the concentration of 125 mM NaCl,the best recovery percentage(11%)was recorded at 30℃.The ability of L.strictissimum to recover germination after salt exposure can be interpreted as an adaptation to the coastal habitats in which it grows.This study provides new insights into the ecophysiology of L.strictissimum seed germination,which could help preserve and implement effective conservation measures for this endangered species with restricted populations.
文摘Gebel Katrina,located in the Saint Catherine Protectorate of South Sinai(Egypt),is a biologically rich area with diverse plant communities shaped by factors such as elevation,slope,soil type,and precipitation.This study was designed to examine the vegetation structure,update the occurrence of endemic taxa,and investigate the impact of environmental conditions and landform types on plant disruption in the region.The primary objective of this study was to analyze the behavior and distribution of the most common species across major environmental gradients.Between 2022 and 2024,49 stands were randomly collected within the study area characterized by relatively uniform vegetation and physiography and represent as much as possible the four major landform types(terraces,slopes,ridges,and gorges).The selected stands were distributed as follows:terraces(12 stands),slopes(9 stands),ridges(9 stands),and gorges(19 stands).For the analysis of the biological spectrum,a growth-form system with four categories was utilized:trees(T),shrubs(S),perennial herbs(PH),and annual herbs(A).Soil analyses were conducted for composite samples from the 49 stands.For each recorded species,nativity,species diversity measurements,endemism,and IUCN conservation status were depicted.Multivariate analysis techniques were used to assess the classification of the 49 stands in various landforms,and ordination with soil variables were applied using different software.A total of 137 taxa were recorded from Gebel Katrina area belonging to 39 families(1 Pteridaceae,1 Ephedraceae,and 37 Angiospermae),of which 16 were endemics,which indicates the mountain's significance as a biodiversity hotspot.Of these endemic taxa,nine were classified as Endangered(EN)and four as Least Concern(LC),together accounting for over 80%of the endemic flora.The largest angiosperm families with the highest numbers of species included Asteraceae,Lamiaceae,Poaceae,Brassicaceae,Caryophyllaceae and Fabaceae.These six families constituted more than 30%of the recorded flora.Shrubs and perennial herbs were the predominant growth forms,collectively comprising over 70%of the total flora.Native taxa comprised the dominant component of the recorded flora,accounting for 80 species(58.4%of the total).In contrast,non-native taxa were limited to two annual grasses.Analysis of IUCN Red List proportions revealed a predominance of EN taxa,accounting for 52 taxa(37.9%),followed by Least Concern(LC)taxa with 36 taxa(26.3%).Together,these two categories constituted over 60%of the total assessed flora.Hierarchical cluster analysis of a presence/absence data matrix(49 stands×91 species after removal of species with occurrences<5%),using the Sørensen(Bray-Curtis)method,identified eight distinct vegetation clusters.Each cluster is characterized by one or more dominant species,distinguished by their highest percentage of occurrence(f)within their respective group.Apart from soil reaction(pH)and diversity indices(species richness and Shannon’s index),ANOVA test showed high significant differences in most of the measured environmental variables among the obtained cluster groups(A-H).Canonical Correspondence Analysis(CCA)showed direct correlations between the 7 examined environmental variables and plant species composition in Gebel Katrina.The eight cluster groups were separated along axes 1 and 2 of the diagram.The species-environment correlations were high for the three axes explaining 63.0%of the cumulative variance.The stands of groups(E)and(G)were correlated with coarse sand,stands of group(B)were highly correlated with electric conductivity(EC),and stands of group(F)were correlated with elevation.The endemic flora of Gebel Katrina faces multiple anthropogenic and environmental threats.Overgrazing by livestock,excessive harvesting of plants for fuelwood and traditional medicinal uses,and habitat degradation due to land-use changes have led to significant depletion of vegetation cover and biodiversity loss.
基金the“Metropolitan Mosquitoes Project”funded by the Swedish Research Council for Environment,Agricultural Sciences and Spatial Planning(Formas,grant number 2016-00364).
文摘Dengue virus(DENV)is a positive-sense single-stranded RNA virus belonging to the genus Flavivirus within the Flaviviridae family.Four serotypes,DENV 1-4,are distributed globally[1].Hanoi metropolitan city is an endemic hotspot for DENV transmission in Vietnam[2,3].The largest outbreak occurred in 2017,with more than 36000 cases and 7 deaths reported,causing by all four serotypes with the predominance of DENV1,following by DENV2[4,5].During the following dengue season,we collected 390 blood and serum samples from 197 hospitalized patients in a national hospital in Hanoi city,Northern Vietnam to identify the circulating DENV serotypes responsible for the 2018-2019 outbreak.
文摘Hepatitis A,a vaccine-preventable liver infection caused by the hepatitis A virus,is undergoing significant epidemiological shifts worldwide.Traditionally considered a disease of childhood in endemic regions,improved sanitation,economic development,and widespread vaccination have led to a decline in incidence,particularly in developed nations.However,this decline has resulted in a growing population of susceptible adults,increasing the risk of severe outbreaks.Additionally,changes in travel patterns,urbanization,and socioeconomic disparities have altered disease distribution,leading to sporadic outbreaks in low-endemicity regions and a rising burden in certain high-risk populations.This review explores the evolving epidemiology of hepatitis A,emphasizing the transition from endemic childhood infections to adult susceptibility.We examine the impact of changing risk factors,including shifting demographics,increased international travel,and regional disparities in vaccination coverage.Furthermore,the review highlights the emergence of new viral strains and their potential implications for disease control.Updated vaccination policies,including targeted immunization strategies and their role in preventing outbreaks,are also discussed.Given these dynamic changes,continued surveillance and public health preparedness tailored to evolving risk groups are crucial for sustained hepatitis A control.By synthesizing recent epidemiological data and policy updates,this review provides insights into the future of hepatitis A prevention and control,offering guidance for clinicians,researchers,and public health professionals.
文摘Malaria is considered one of the major causes of travel-related morbidity and mortality,especially among non-immune travelers from non-endemic countries to the endemic regions.According to a multicenter study from the GeoSentinel surveillance network,malaria was the most frequent cause of fever in 21%of returning travelers,followed by dengue,typhoid fever,chikungunya and rickettsiosis[1].Individuals traveling from regions without malaria transmission to areas where it is endemic face a heightened risk of contracting the disease due to their lack of immunity.Despite the official malaria-free status of the Russian Federation since 2010,annual cases of severe Plasmodium(P.)falciparum malaria continue to be reported[2].This underscores the necessity for heightened clinical vigilance and improved preventive strategies especially in non-endemic settings.
基金supported by the Global Genome Initiative for Gardens(GGI-Gardens Award),United States Botanic Garden and Botanic Gardens Conservation International,United Kingdom(Grant No.GGI/2024/1).
文摘The Andaman Islands,part of the Indo-Burma biodiversity hotspot,holds unique florawith many endemic and threatened species.However,this fragile diversity is under increasing pressure from infrastructure expansion,climate change and habitat fragmentation.The recently announced Great Nicobar Island Development project by the Government of India,which includes an international transhipment terminal,airport,township and power plant,if implemented,would cause major habitat loss and fragmentation,possibly leading to species extinctions.
文摘Hepatitis B virus(HBV)infection is a serious global public health problem.The infection may be transmitted through sexual intercourse,parenteral contact or from an infected mother to the baby at birth and,if contracted early in life,may lead to chronic liver disease,including cirrhosis and hepatocellular carcinoma.On the basis of the HBV carrier rate,the world can be divided in 3 regions of high,medium and low endemicity.The major concern is about high endemicity countries,where the most common route of infection remains vertical transmission from mother to child.Screening of all pregnant women and passive immunization with human hepatitis B immunoglobulin are not affordable for many developing countries.The infection rate can be reduced by modifying behavior,improving individual education,testing all blood donations,assuring asepsis in clinical practice and screening all pregnant women.However,availability of a safe and efficacious vaccine and adoption of appropriate immunization strategies are the most effective means to prevent HBV infection and its consequences.The unsolved problem for poorest countries,where the number of people currently infected is high,is the cost of the vaccine.A future challenge is to overcome the social and economic hurdles of maintaining and improving a prevention policy worldwide to reduce the global burden of the disease.
文摘Objective:To investigate resistance and safety of HHPG-19K in treating non-small cell lung cancer patients.Methods:A total of 30 cases were selected and randomly divided into 5 groups:three HHPG-19K groups of different dosage(60 μg/kg/day,100 μ g/kg/day,200 μ g/ kg/day),positive control group(Filgrastim,namely G-CSF5 μ g/kg/day) and negative control group.Safety indexes of 5 groups were observed and compared.Results:All patients had adverse event(100%) in three HHPG-19K groups,and increased ALP,ALT and AST were main events.The degree was mild to moderate.There was no significant difference in the incidence of adverse event between dosage groups and positive control group no difference.But the incidence of negative control group was 13%,which was significantly lower than dosage groups and positive control group.Conclusions:Non-small cell lung cancer patients have satisfactory tolerance to HHPG-19K,and have no resistance.Besides,dosage at 100 μ g/kg is the most safe.
