Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and ...Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and systemic inflammation,as well as whether this association is modified by indoor particulate matter and the underlying mechanisms.In this prospective repeated-measure study among 66 participants,indoor airborne mi-crobiome was characterized using amplicon sequencing and qPCR.Indoor fine particulate matter(PM_(2.5))and inhalable particulate matter(PM10)were measured.Systemic inflammatory biomarkers were assessed,including white blood cell(WBC),neutrophil(NEUT),monocyte,eosinophil counts,and their proportions.Targeted serum amino acid metabolomics were conducted to explore the underlying mechanisms.Linear mixed-effect models re-vealed that bacterial and fungal Simpson diversity were significantly associated with decreased WBC and NEUT.For example,for each interquartile range increase in the bacterial Simpson diversity,WBC and NEUT changed by-4.53%(95%CI:-8.25%,-0.66%)and-5.95%(95%CI:-11.3%,-0.27%),respectively.Notably,increased inflammatory risks of airborne microbial exposure were observed when indoor PM_(2.5) and PM10 levels were below the WHO air quality guidelines.Mediation analyses indicated that dopamine metabolism partially mediated the anti-inflammatory effects of fungal diversity exposure.Overall,our study indicated protection from a diverse indoor microbial environment on cardiovascular health and proposed an underlying mechanism through amino acid metabolism.Additionally,health risks associated with microbial exposure deserve more attention in con-texts of low indoor particulate matter pollution.Further research is necessary to fully disentangle the complex relationships between indoor microbiome,air pollutants,and human health.展开更多
Perception of air pollution is subjective and context-dependent.Previous studies exploring the association between measured air pollution and perceived air quality mainly focused on air pollution levels measured in th...Perception of air pollution is subjective and context-dependent.Previous studies exploring the association between measured air pollution and perceived air quality mainly focused on air pollution levels measured in the residence-based(RB)or regional context,overlooking the mobility-based(MB)context in which people are exposed to air pollution.This study measures air pollution levels in MB,RB,and regional contexts and examines their relationships with perceived air quality across different neighborhoods and gender sub-groups of Hong Kong,China to investigate how people perceive air quality.The results indicate that particulate matter 2.5(PM_(2.5))measured in RB and the regional context significantly contributes to people’s perceived air quality compared to MB PM_(2.5).Individuals in Central and Western district of Hong Kong rely on RB,regional and MB PM_(2.5) to assess air pollution.In Sham Shui Po,RB PM_(2.5) exhibits the highest influence on people’s perceived air quality,followed by regional PM_(2.5).Women’s perceived air quality is strongly related to their RB PM_(2.5) exposure,while men’s perceived air quality is associated with both RB PM_(2.5) and regional PM_(2.5) levels.We conclude that neighborhood effects and mobility levels are the two most important factors influencing the association between meas-ured air pollution and perceived air quality.We reveal that the neighborhood effect averaging problem(NEAP)influences the associ-ation between perceived air quality and measured air pollution levels in a way that differs from health outcome-related studies.Effect-ive measures are needed to improve the public’s awareness of air pollution,and scientific control should be implemented to reduce pub-lic exposure.展开更多
The effects of nitrogen(N)deposition on forest soil organic carbon(SOC)are largely unclear,likely due to the divergent responses of particulate(POC)and mineral-associated carbon(MAOC).Conventional understory inorganic...The effects of nitrogen(N)deposition on forest soil organic carbon(SOC)are largely unclear,likely due to the divergent responses of particulate(POC)and mineral-associated carbon(MAOC).Conventional understory inorganic N(UIN)additions neglect canopy processes and the impacts of organic N,potentially misevaluating N deposition effects.This study was conducted in a long-term N addition experiment established in a Moso bamboo forest,which included six treatments combining canopy and understory N additions with organic(urea glycine)and inorganic(NH_(4)NO_(3))forms at a rate of 50 kg N·ha^(-1)·yr^(-1).Litterbags were installed for a two-year decomposition experiment and collected at quarterly intervals,together with concurrent soil sampling under litterbags at 0–10 cm depth.We aimed to examine the effects of canopy vs.understory N addition and organic vs.inorganic N form on soil POC and MAOC concentrations.Our results showed that canopy N additions significantly reduced POC(ased POC-15.9%)but did not affect MAOC(P>0.05).Conversely,understory N additions significantly incre(30.9%)and decreased MAOC(and fungal diversity(FuD),-28.9%).Canopy N additions decreased POC by enhancing peroxidase activity while understory N additions promoted POC by inhibiting litter decomposition.Additionally,understory N addition-induced soil acidification decreased soil Ca^(2+)concentration,microbial carbon use efficiency,and bacterial necromass C,as well as the release of litter water-soluble compounds,thereby inhibiting MAOC.Moreover,nitrogen forms(organic vs.inorganic)had no effect on SOC fractions.Our findings underscore that canopy and understory N addition approaches differentially regulate SOC fractions by altering litter decomposition–microbial–mineral interactions,and the understory approach may overestimate soil POC gain and MAOC loss driven by atmospheric N deposition.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFC3702704)the National Natural Science Foundation of China(Nos.22376005,22076006 and 82073506).
文摘Microorganisms constitute an essential component in the indoor environment,which is closely related to hu-man health.However,there is limited evidence regarding the associations between indoor airborne microbiome and systemic inflammation,as well as whether this association is modified by indoor particulate matter and the underlying mechanisms.In this prospective repeated-measure study among 66 participants,indoor airborne mi-crobiome was characterized using amplicon sequencing and qPCR.Indoor fine particulate matter(PM_(2.5))and inhalable particulate matter(PM10)were measured.Systemic inflammatory biomarkers were assessed,including white blood cell(WBC),neutrophil(NEUT),monocyte,eosinophil counts,and their proportions.Targeted serum amino acid metabolomics were conducted to explore the underlying mechanisms.Linear mixed-effect models re-vealed that bacterial and fungal Simpson diversity were significantly associated with decreased WBC and NEUT.For example,for each interquartile range increase in the bacterial Simpson diversity,WBC and NEUT changed by-4.53%(95%CI:-8.25%,-0.66%)and-5.95%(95%CI:-11.3%,-0.27%),respectively.Notably,increased inflammatory risks of airborne microbial exposure were observed when indoor PM_(2.5) and PM10 levels were below the WHO air quality guidelines.Mediation analyses indicated that dopamine metabolism partially mediated the anti-inflammatory effects of fungal diversity exposure.Overall,our study indicated protection from a diverse indoor microbial environment on cardiovascular health and proposed an underlying mechanism through amino acid metabolism.Additionally,health risks associated with microbial exposure deserve more attention in con-texts of low indoor particulate matter pollution.Further research is necessary to fully disentangle the complex relationships between indoor microbiome,air pollutants,and human health.
基金Under the auspices of the Hong Kong Research Grants Council(No.14605920,14606922,14603724,C4023-20GF,8601219,8601242,3110151)a Grant from the Research Committee on Research Sustainability of Major Research Grants Council Funding Schemes of the Chinese University of Hong Kong(CUHK,No.3133235)the Vice-Chancellor’s One-off Discretionary Fund of CUHK(No.4930787)。
文摘Perception of air pollution is subjective and context-dependent.Previous studies exploring the association between measured air pollution and perceived air quality mainly focused on air pollution levels measured in the residence-based(RB)or regional context,overlooking the mobility-based(MB)context in which people are exposed to air pollution.This study measures air pollution levels in MB,RB,and regional contexts and examines their relationships with perceived air quality across different neighborhoods and gender sub-groups of Hong Kong,China to investigate how people perceive air quality.The results indicate that particulate matter 2.5(PM_(2.5))measured in RB and the regional context significantly contributes to people’s perceived air quality compared to MB PM_(2.5).Individuals in Central and Western district of Hong Kong rely on RB,regional and MB PM_(2.5) to assess air pollution.In Sham Shui Po,RB PM_(2.5) exhibits the highest influence on people’s perceived air quality,followed by regional PM_(2.5).Women’s perceived air quality is strongly related to their RB PM_(2.5) exposure,while men’s perceived air quality is associated with both RB PM_(2.5) and regional PM_(2.5) levels.We conclude that neighborhood effects and mobility levels are the two most important factors influencing the association between meas-ured air pollution and perceived air quality.We reveal that the neighborhood effect averaging problem(NEAP)influences the associ-ation between perceived air quality and measured air pollution levels in a way that differs from health outcome-related studies.Effect-ive measures are needed to improve the public’s awareness of air pollution,and scientific control should be implemented to reduce pub-lic exposure.
文摘The effects of nitrogen(N)deposition on forest soil organic carbon(SOC)are largely unclear,likely due to the divergent responses of particulate(POC)and mineral-associated carbon(MAOC).Conventional understory inorganic N(UIN)additions neglect canopy processes and the impacts of organic N,potentially misevaluating N deposition effects.This study was conducted in a long-term N addition experiment established in a Moso bamboo forest,which included six treatments combining canopy and understory N additions with organic(urea glycine)and inorganic(NH_(4)NO_(3))forms at a rate of 50 kg N·ha^(-1)·yr^(-1).Litterbags were installed for a two-year decomposition experiment and collected at quarterly intervals,together with concurrent soil sampling under litterbags at 0–10 cm depth.We aimed to examine the effects of canopy vs.understory N addition and organic vs.inorganic N form on soil POC and MAOC concentrations.Our results showed that canopy N additions significantly reduced POC(ased POC-15.9%)but did not affect MAOC(P>0.05).Conversely,understory N additions significantly incre(30.9%)and decreased MAOC(and fungal diversity(FuD),-28.9%).Canopy N additions decreased POC by enhancing peroxidase activity while understory N additions promoted POC by inhibiting litter decomposition.Additionally,understory N addition-induced soil acidification decreased soil Ca^(2+)concentration,microbial carbon use efficiency,and bacterial necromass C,as well as the release of litter water-soluble compounds,thereby inhibiting MAOC.Moreover,nitrogen forms(organic vs.inorganic)had no effect on SOC fractions.Our findings underscore that canopy and understory N addition approaches differentially regulate SOC fractions by altering litter decomposition–microbial–mineral interactions,and the understory approach may overestimate soil POC gain and MAOC loss driven by atmospheric N deposition.
