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1.
Nat Plants ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997433

RESUMO

Rice is one of the most important staple food and model species in plant biology, yet its quantitative proteomes are largely uncharacterized. Here we quantify the relative protein levels of over 15,000 genes across major rice tissues using a tandem mass tag strategy followed by intensive fractionation and mass spectrometry. We identify tissue-specific and tissue-enriched proteins that are linked to the functional specificity of individual tissues. Proteogenomic comparison of rice and Arabidopsis reveals conserved proteome expression, which differs from mammals in that there is a strong separation of species rather than tissues. Notably, profiling of N6-methyladenosine (m6A) across the rice major tissues shows that m6A at untranslated regions is negatively correlated with protein abundance and contributes to the discordance between RNA and protein levels. We also demonstrate that our data are valuable for identifying novel genes required for regulating m6A methylation. Taken together, this study provides a paradigm for further research into rice proteogenome.

2.
Sci Total Environ ; : 174672, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002582

RESUMO

Tropical forests are sensitive to nitrogen (N) and phosphorus (P) availability, and under nutrient application the variation of soil organic carbon (SOC) preserving mechanism remains to be explored. To reveal the forest-specific SOC preservation via biochemical selection in response to nutrient application, we investigated a monoculture (Acacia plantation) and a multispecies forest both with chronic fertilization in subtropical regions, and measured specific fingerprints of plant- and microbial-derived C compounds. In addition, to quantify the effect of P application on SOC content among tropical forests, we conducted a meta-analysis by compiling 125 paired measurements in field experiments from 62 studies. In our field experiment, microbial community composition and activity mediated forest-specific responses of SOC compounds to P addition. The shift of community composition from fungi towards Gram-positive bacteria in the Acacia plantation by P addition led to the consumption of microbial residual C (MRC) as C source; in comparison, P addition increased plant species with less complex lignin substrates and induced microbial acquisition for N sources, thus stimulated the decomposition of both plant- and microbial-derived C. Same with our field experiment, bulk SOC content had neutral response to P addition among tropical forests in the meta-analysis, although divergences could happen among experimental durations and secondary tree species. Close associations among SOC compounds with biotic origins and mineral associated organic C (MAOC) in the multispecies forest suggested contributions of both plant- and microbial-derive C to SOC stability. Regarding that fungal MRC closely associated with MAOC and consisted of soil N pool which tightly coupled to SOC pool, the reduce of fungal MRC by chronic P addition was detrimental to SOC accumulation and stability in tropical forests.

3.
J Hazard Mater ; 472: 134506, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38714059

RESUMO

BACKGROUND: Increasing studies linked outdoor air pollution (OAP), indoor environmental factors (IEFs), and antibiotics use (AU) with the first wave of allergies (i.e., asthma, allergic rhinitis, and eczema), yet the role of their exposures on children's second wave of allergy (i.e., food allergy) are unknown. OBJECTIVES: To investigate the association between exposure to OAP and IEFs and childhood doctor-diagnosed food allergy (DFA) during the pre-pregnancy, prenatal, early postnatal, and current periods, and to further explore the effect of OAP and IEFs on DFA in children co-exposed to antibiotics. METHODS: A retrospective cohort study involving 8689 preschoolers was carried out in Changsha, China. Data on the health outcomes, antibiotic use, and home environment of each child were collected through a questionnaire. Temperature and air pollutants data were obtained from 8 and 10 monitoring stations in Changsha, respectively. Exposure levels to temperature and air pollutants at individual home addresses were calculated by the inverse distance weighted (IDW) method. Multiple logistic regression models were employed to assess the associations of childhood DFA with exposure to OAP, IEF, and AU. RESULTS: Childhood ever doctor-diagnosed food allergy (DFA) was linked to postnatal PM10 exposure with OR (95% CI) of 1.18 (1.03-1.36), especially for CO and O3 exposure during the first year with ORs (95% CI) = 1.08 (1.00-1.16) and 1.07 (1.00-1.14), as well as SO2 exposure during the previous year with OR (95% CI) of 1.13 (1.02-1.25). The role of postnatal air pollution is more important for the risk of egg, milk and other food allergies. Renovation-related IAP (new furniture) and dampness-related indoor allergens exposures throughout all time windows significantly increased the risk of childhood DFA, with ORs ranging from 1.23 (1.03-1.46) to 1.54 (1.29-1.83). Furthermore, smoke-related IAP (environmental tobacco smoke [ETS], parental and grandparental smoking) exposure during pregnancy, first year, and previous year was related to DFA. Additionally, exposure to pet-related indoor allergens (cats) during first year and total plant-related allergens (particularly nonflowering plants) during previous year were associated with DFA. Moreover, exposure to plant-related allergy during first and previous year was specifically associated with milk allergy, while keeping cats during first year increased the risk of fruits/vegetables allergy. Life-time and early-life AU was associated with the increased risk of childhood DFA with ORs (95% CI) = 1.57 (1.32-1.87) and 1.46 (1.27-1.67), including different types food allergies except fruit/vegetable allergy. CONCLUSIONS: Postnatal OAP, life-time and early-life IEFs and AU exposure played a vital role in the development of DFA, supporting the "fetal origin of childhood FA" hypothesis.


Assuntos
Antibacterianos , Hipersensibilidade Alimentar , Humanos , Feminino , Pré-Escolar , Antibacterianos/efeitos adversos , Masculino , Estudos Retrospectivos , China/epidemiologia , Gravidez , Exposição Ambiental/efeitos adversos , Lactente , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar em Ambientes Fechados/efeitos adversos
5.
Neurol Ther ; 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38819614

RESUMO

INTRODUCTION: Vestibular migraine (VM) is a prevalent vestibular disorder characterized by episodic vertigo. However, the relationship between photophobia and visual triggers in VM remains unexplored. We investigated the correlation of photophobia during the VM attack with interictal photosensitivity and visually triggering dizziness in patients with VM. METHODS: We enrolled patients diagnosed with VM, with or without photophobia, across seven specialized vertigo and headache clinics in China. Healthy individuals were also included as a control group. Using a cross-sectional survey design, we collected data related to light intensity and dizziness frequency triggered by flicker, glare, and eyestrain using the Headache Triggers Sensitivity and Avoidance Questionnaire. RESULTS: A total of 366 patients were recruited. The photosensitivity and frequency of dizziness induced by flicker, glare, and eyestrain observed in patients with VM and photophobia were significantly elevated compared with those in patients without photophobia and control participants (P < 0.001). A significant positive correlation was observed between photosensitivity levels and dizziness frequency triggered by flicker, glare, and eyestrain in patients with VM and photophobia (P < 0.001). CONCLUSIONS: This study unequivocally established a positive association of ictal photophobia with interictal photosensitivity and visually triggering dizziness, strongly advocating the need for further research on exposure-based therapies for managing VM. CLINICAL TRIALS REGISTRATION: ClinicalTrial.gov Identifier, NCT04939922, retrospectively registered, 14th June 2021.

6.
Environ Res ; 255: 119188, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38795950

RESUMO

The efficient use of livestock and poultry manure waste has become a global challenge, with microorganisms playing an important role. To investigate the impact of novel ammonifying microorganism cultures (NAMC) on microbial community dynamics and carbon and nitrogen metabolism, five treatments [5% (v/w) sterilized distilled water, Amm-1, Amm-2, Amm-3, and Amm-4] were applied to cow manure compost. Inoculation with NAMC improved the structure of bacterial and fungal communities, enriched the populations of the functional microorganisms, enhanced the role of specific microorganisms, and promoted the formation of tight modularity within the microbial network. Further functional predictions indicated a significant increase in both carbon metabolism (CMB) and nitrogen metabolism (NMB). During the thermophilic phase, inoculated NAMC treatments boosted carbon metabolism annotation by 10.55%-33.87% and nitrogen metabolism annotation by 26.69%-63.11. Structural equation modeling supported the NAMC-mediated enhancement of NMB and CMB. In conclusion, NAMC inoculation, particularly with Amm-4, enhanced the synergistic interaction between bacteria and fungi. This collaboration promoted enzymatic catabolic and synthetic processes, resultng in positive feedback loops with the endogenous microbial community. Understanding these mechanisms not only unravels how ammonifying microorganisms influence microbial communities but also paves the way for the development of the composting industry and global waste management practices.


Assuntos
Carbono , Compostagem , Esterco , Nitrogênio , Nitrogênio/metabolismo , Esterco/microbiologia , Animais , Carbono/metabolismo , Fungos/metabolismo , Microbiota , Bactérias/metabolismo , Microbiologia do Solo , Bovinos
7.
Pharmacol Res ; 204: 107217, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777110

RESUMO

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway functions as a central hub for transmitting signals from more than 50 cytokines, playing a pivotal role in maintaining hematopoiesis, immune balance, and tissue homeostasis. Dysregulation of this pathway has been implicated in various diseases, including immunodeficiency, autoimmune conditions, hematological disorders, and certain cancers. Proteins within this pathway have emerged as effective therapeutic targets for managing these conditions, with various approaches developed to modulate key nodes in the signaling process, spanning from receptor engagement to transcription factor activation. Following the success of JAK inhibitors such as tofacitinib for RA treatment and ruxolitinib for managing primary myelofibrosis, the pharmaceutical industry has obtained approvals for over 10 small molecule drugs targeting the JAK-STAT pathway and many more are at various stages of clinical trials. In this review, we consolidate key strategies employed in drug discovery efforts targeting this pathway, with the aim of contributing to the collective understanding of small molecule interventions in the context of JAK-STAT signaling. We aspire that our endeavors will contribute to advancing the development of innovative and efficacious treatments for a range of diseases linked to this pathway dysregulation.


Assuntos
Descoberta de Drogas , Janus Quinases , Fatores de Transcrição STAT , Transdução de Sinais , Humanos , Janus Quinases/metabolismo , Janus Quinases/antagonistas & inibidores , Fatores de Transcrição STAT/metabolismo , Fatores de Transcrição STAT/antagonistas & inibidores , Descoberta de Drogas/métodos , Animais , Transdução de Sinais/efeitos dos fármacos , Inibidores de Janus Quinases/uso terapêutico , Inibidores de Janus Quinases/farmacologia , Terapia de Alvo Molecular
8.
Environ Pollut ; 353: 124127, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38759746

RESUMO

Allergic asthma is a chronic inflammatory airway disease with a high mortality rate and a rapidly increasing prevalence in recent decades that is closely linked to environmental change. Previous research found that high humidity (HH) and the traffic-related air pollutant NO2 both aggregated allergic asthma. Their combined effect and mechanisms on asthma exacerbation, however, are unknown. Our study aims to toxicologically clarify the role of HH (90%) and NO2 (5 ppm) on allergic asthma. Ninety male Balb/c mice were randomly assigned to one of six groups (n = 15 in each): saline control, ovalbumin (OVA)-sensitized, OVA + HH, OVA + NO2, OVA + HH + NO2, and OVA + HH + NO2+Capsazepine (CZP). After 38 days of treatment, the airway function, pathological changes in lung tissue, blood inflammatory cells, and oxidative stress and inflammatory biomarkers were comprehensively assessed. Co-exposure to HH and NO2 exacerbated histopathological changes and airway hyperresponsiveness, increased IgE, oxidative stress markers malonaldehyde (MDA) and allergic asthma-related inflammation markers (IL-1ß, TNF-α and IL-17), and upregulated the expressions of the transient receptor potential (TRP) ion channels (TRPA1, TRPV1 and TRPV4). Our findings show that co-exposure to HH and NO2 disrupted the Th1/Th2 immune balance, promoting allergic airway inflammation and asthma susceptibility, and increasing TRPV1 expression, whereas CZP reduced TRPV1 expression and alleviated allergic asthma symptoms. Thus, therapeutic treatments that target the TRPV1 ion channel have the potential to effectively manage allergic asthma.


Assuntos
Poluentes Atmosféricos , Asma , Umidade , Pulmão , Camundongos Endogâmicos BALB C , Dióxido de Nitrogênio , Estresse Oxidativo , Canais de Cátion TRPV , Animais , Asma/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Masculino , Camundongos , Canais de Cátion TRPV/metabolismo , Canais de Cátion TRPV/genética , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Poluentes Atmosféricos/toxicidade , Dióxido de Nitrogênio/toxicidade , Inflamação/metabolismo , Canal de Cátion TRPA1/metabolismo , Canal de Cátion TRPA1/genética , Imunoglobulina E , Capsaicina/análogos & derivados
9.
Sci Bull (Beijing) ; 69(12): 1991-2000, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38755089

RESUMO

Spartina alterniflora has rapidly and extensively encroached on China's coastline over the past decades. Among the coastal areas invaded by S. alterniflora, at most 93% are mudflats. However, the effect of S. alterniflora invasion on soil organic carbon (SOC) stocks of coastal mudflats has not been systematically studied on a national scale. Here, we quantified the nationwide changes in SOC stocks in coastal mudflats associated with S. alterniflora invasion between 1990 and 2020. We found that S. alterniflora invasion significantly enhanced SOC stocks in coastal China. Nonetheless, the benefit of S. alterniflora invasion of coastal SOC stock may be weakened by continuing human intervention. We found that S. alterniflora invading mudflats added 2.3 Tg SOC stocks to China's coastal blue carbon, while 1.78 Tg SOC stocks were lost mainly due to human activities, resulted in a net SOC stock gain of 0.52 Tg C. These findings overturned the traditionally thought that S. alterniflora invasion would reduce ecosystem services by highlighting that the historical invasion of S. alterniflora has broadly and consistently enhanced blue carbon stock in coastal China.


Assuntos
Sequestro de Carbono , Carbono , Ecossistema , Espécies Introduzidas , Poaceae , Solo , China , Solo/química , Carbono/análise , Humanos
10.
BMC Genomics ; 25(1): 354, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594645

RESUMO

The homeodomain-leucine zipper (HD-Zip) gene family plays a pivotal role in plant development and stress responses. Nevertheless, a comprehensive characterization of the HD-Zip gene family in kiwifruit has been lacking. In this study, we have systematically identified 70 HD-Zip genes in the Actinidia chinensis (Ac) genome and 55 in the Actinidia eriantha (Ae) genome. These genes have been categorized into four subfamilies (HD-Zip I, II, III, and IV) through rigorous phylogenetic analysis. Analysis of synteny patterns and selection pressures has provided insights into how whole-genome duplication (WGD) or segmental may have contributed to the divergence in gene numbers between these two kiwifruit species, with duplicated gene pairs undergoing purifying selection. Furthermore, our study has unveiled tissue-specific expression patterns among kiwifruit HD-Zip genes, with some genes identified as key regulators of kiwifruit responses to bacterial canker disease and postharvest processes. These findings not only offer valuable insights into the evolutionary and functional characteristics of kiwifruit HD-Zips but also shed light on their potential roles in plant growth and development.


Assuntos
Actinidia , Proteínas de Homeodomínio , Proteínas de Homeodomínio/genética , Genoma de Planta , Filogenia , Actinidia/genética , Zíper de Leucina/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Perfilação da Expressão Gênica
11.
Am J Physiol Regul Integr Comp Physiol ; 326(6): R567-R577, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38646812

RESUMO

Postexercise reduction in blood pressure, termed postexercise hypotension (PEH), is relevant for both acute and chronic health reasons and potentially for peripheral cardiovascular adaptations. We investigated the interactive effects of exercise intensity and recovery postures (seated, supine, and standing) on PEH. Thirteen normotensive men underwent a V̇o2max test on a cycle ergometer and five exhaustive constant load trials to determine critical power (CP) and the gas exchange threshold (GET). Subsequently, work-matched exercise trials were performed at two discrete exercise intensities (10% > CP and 10% < GET), with 1 h of recovery in each of the three postures. For both exercise intensities, standing posture resulted in a more substantial PEH (all P < 0.01). For both standing and seated recovery postures, the higher exercise intensity led to larger reductions in systolic [standing: -33 (11) vs. -21 (8) mmHg; seated: -34 (32) vs. -17 (37) mmHg, P < 0.01], diastolic [standing: -18 (7) vs. -8 (5) mmHg; seated: -10 (10) vs. -1 (4) mmHg, P < 0.01], and mean arterial pressures [-13 (8) vs. -2 (4) mmHg, P < 0.01], whereas in the supine recovery posture, the reduction in diastolic [-9 (9) vs. -4 (3) mmHg, P = 0.08) and mean arterial pressures [-7 (5) vs. -3 (4) mmHg, P = 0.06] was not consistently affected by prior exercise intensity. PEH is more pronounced during recovery from exercise performed above CP versus below GET. However, the effect of exercise intensity on PEH is largely abolished when recovery is performed in the supine posture.NEW & NOTEWORTHY The magnitude of postexercise hypotension is greater following the intensity above the critical power in a standing position.


Assuntos
Pressão Sanguínea , Exercício Físico , Hipotensão Pós-Exercício , Postura , Humanos , Masculino , Exercício Físico/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Postura/fisiologia , Hipotensão Pós-Exercício/fisiopatologia , Adulto Jovem , Decúbito Dorsal , Recuperação de Função Fisiológica , Posição Ortostática , Postura Sentada , Hipotensão/fisiopatologia , Consumo de Oxigênio
12.
Br J Educ Psychol ; 94(2): 622-641, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38443324

RESUMO

BACKGROUND: Socio-emotional skills are critical to life outcomes such as achievement, well-being and job success. However, existing research has mostly focused on the consequences of socio-emotional skills, with less attention devoted to the role of school climate in the deployment of these skills. AIMS: This study investigated the role of school climate in socio-emotional skills. More specifically, we investigated whether cooperative or competitive school climates are associated with students' socio-emotional skills. SAMPLE: Our study utilized data from the OECD Survey on Social and Emotional Skills, collected from 10 cities across nine countries. Participants were 60,985 students, including 31,187 10-year-olds (49.70% females) and 29,798 15-year-olds (51.6% females). METHODS: We conducted multilevel structural equation modelling to test whether cooperative and competitive climates were associated with socio-emotional skills. These skills include five broad domain skills and 15 more specific skills: task performance (self-control, responsibility and persistence), emotion regulation (stress resistance, emotional control and optimism), collaboration (empathy, trust and cooperation), open-mindedness (tolerance, curiosity and creativity) and engaging with others (sociability, assertiveness and energy). RESULTS: Our findings indicated a positive relationship between a cooperative climate and socio-emotional skills. In contrast, the relationship between a competitive climate and socio-emotional skills was primarily negative. CONCLUSION: This study highlights the contrasting roles of cooperative and competitive climates in students' socio-emotional skills.


Assuntos
Instituições Acadêmicas , Habilidades Sociais , Estudantes , Humanos , Feminino , Masculino , Adolescente , Criança , Estudantes/psicologia , Comportamento Cooperativo , Regulação Emocional/fisiologia , Comportamento Competitivo/fisiologia , Meio Social
13.
Br J Educ Psychol ; 94(2): 499-517, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38243129

RESUMO

BACKGROUND: Socio-economic status is one of the most important factors shaping students' motivation and achievement but has seldom been explored in relation to achievement goals. AIMS: This study aimed to investigate whether mastery-approach goals explain the link between SES and key learning-related outcomes (mediation) and whether SES modifies the relationship between mastery-approach goals and these outcomes (moderation). SAMPLE: Data came from 595,444 students nested in 21,322 schools across 77 countries. METHODS: Data were analysed using multilevel-moderated mediation analyses. RESULTS: We found significant mediation and moderation. In terms of mediation, mastery-approach goals mediated the association between family SES and learning-related outcomes. However, a different pattern emerged for school SES, as students in higher SES schools had lower mastery-approach goals. In terms of moderation, we found that family SES strengthened the association between mastery-approach goals and learning-related outcomes. However, the association between mastery-approach goals and learning-related outcomes was weaker in higher SES schools. CONCLUSION: Theoretical and practical implications for the achievement goal approach to achievement motivation are discussed.


Assuntos
Sucesso Acadêmico , Objetivos , Classe Social , Humanos , Feminino , Masculino , Criança , Adolescente , Estudantes/psicologia , Instituições Acadêmicas , Motivação , Logro
14.
J Mater Chem B ; 12(5): 1317-1329, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38229564

RESUMO

Bacterial biofilm infection is a serious obstacle to clinical therapeutics. Photodynamic therapy (PDT) plays a dynamic role in combating biofilm infection by utilizing reactive oxygen species (ROS)-induced bacterial oxidation injury, showing advantages of mild side effects, spatiotemporal controllability and little drug resistance. However, superfluous glutathione (GSH) present in biofilm and bacteria corporately reduces ROS levels and seriously affects PDT efficiency. Herein, we have constructed a Cu2+-infused porphyrin metal-organic framework (MOF@Cu2+) for the enhanced photodynamic combating of biofilm infection by the maximum depletion of GSH. Our results show that the released Cu2+ from porphyrin MOF@Cu2+ could not only oxidize GSH in biofilm but also consume GSH leaked from ROS-destroyed bacteria, thus greatly weakening the antioxidant system in biofilm and bacteria and dramatically improving the ROS levels. As expected, our dual-enhanced PDT nanoplatform exhibits a strong biofilm eradication ability both in vitro and in an in vivo biofilm-infected mouse model. In addition, Cu2+ can promote biofilm-infected wound closing by provoking cell immigration, collagen sediment and angiogenesis. Besides, no apparent toxicity was detected after treatment with MOF@Cu2+. Overall, our design offers a new paradigm for photodynamic combating biofilm infection.


Assuntos
Fotoquimioterapia , Porfirinas , Animais , Camundongos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Cobre/farmacologia , Porfirinas/farmacologia , Espécies Reativas de Oxigênio , Glutationa , Bactérias , Biofilmes
15.
Nano Lett ; 24(2): 657-666, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38180824

RESUMO

The cooling power provided by radiative cooling is unwanted during cold hours. Therefore, self-adaptive regulation is desired for radiative cooling, especially in all-weather applications. However, current routes for radiative cooling regulation are constrained by substrates and complicated processing. Here, self-adaptive radiative cooling regulation on various potential substrates (transparent wood, PET, normal glass, and cement) was achieved by a Fabry-Perot structure consisting of a silver nanowires (AgNWs) bottom layer, PMMA spacer, and W-VO2 top layer. The emissivity-modulated transparent wood (EMTW) exhibits an emissivity contrast of 0.44 (ε8-13-L = ∼0.19 and ε8-13-H = ∼0.63), which thereby yields considerable energy savings across different climate zones. The emissivity contrast can be adjusted by varying the spinning parameters during the deposition process. Positive emissivity contrast was also achieved on three other industrially relevant substrates via this facile and widely applicable route. This proves the great significance of the approach to the promotion and wide adoption of radiative cooling regulation concept in the built environment.

16.
Glob Chang Biol ; 30(1): e17007, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37916453

RESUMO

Mangroves play a globally significant role in carbon capture and storage, known as blue carbon ecosystems. Yet, there are fundamental biogeochemical processes of mangrove blue carbon formation that are inadequately understood, such as the mechanisms by which mangrove afforestation regulates the microbial-driven transfer of carbon from leaf to below-ground blue carbon pool. In this study, we addressed this knowledge gap by investigating: (1) the mangrove leaf characteristics using state-of-the-art FT-ICR-MS; (2) the microbial biomass and their transformation patterns of assimilated plant-carbon; and (3) the degradation potentials of plant-derived carbon in soils of an introduced (Sonneratia apetala) and a native mangrove (Kandelia obovata). We found that biogeochemical cycling took entirely different pathways for S. apetala and K. obovata. Blue carbon accumulation and the proportion of plant-carbon for native mangroves were high, with microbes (dominated by K-strategists) allocating the assimilated-carbon to starch and sucrose metabolism. Conversely, microbes with S. apetala adopted an r-strategy and increased protein- and nucleotide-biosynthetic potentials. These divergent biogeochemical pathways were related to leaf characteristics, with S. apetala leaves characterized by lower molecular-weight, C:N ratio, and lignin content than K. obovata. Moreover, anaerobic-degradation potentials for lignin were high in old-aged soils, but the overall degradation potentials of plant carbon were age-independent, explaining that S. apetala age had no significant influences on the contribution of plant-carbon to blue carbon. We propose that for introduced mangroves, newly fallen leaves release nutrient-rich organic matter that favors growth of r-strategists, which rapidly consume carbon to fuel growth, increasing the proportion of microbial-carbon to blue carbon. In contrast, lignin-rich native mangrove leaves shape K-strategist-dominated microbial communities, which grow slowly and store assimilated-carbon in cells, ultimately promoting the contribution of plant-carbon to the remarkable accumulation of blue carbon. Our study provides new insights into the molecular mechanisms of microbial community responses during reforestation in mangrove ecosystems.


Assuntos
Sequestro de Carbono , Ecossistema , Lignina , Folhas de Planta , Carbono , Solo , Áreas Alagadas
17.
Mar Pollut Bull ; 199: 115934, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38118399

RESUMO

Mangroves sequester and store large area-specific quantities of blue carbon (C) and essential nutrients such as nitrogen (N) and phosphorous (P). Quantifying C and nutrient burial rates in mangroves across a centennial time span and relating these rates to mangrove habitat is fundamental for elucidating the role of mangroves in carbon and nutrient budgets and their responses to environmental changes. However, relevant data are very limited in China. In this study, we used the radionuclides (210Pb and 137Cs) to determine chronologies and C, N and P burial rates in two mangrove forests located at different geomorphologic settings in NE Hainan Island, China. We found that the temporal patterns of C, N and P burial rates since 1900 fitted a quadratic function with a notable increase after 1960s in both mangroves, which coincided with the rapid development of coastal aquaculture since 1960s in NE Hainan and the subsequent coastal water eutrophication in this area. Sediment accretion rate (SAR) and mass accumulation rate (MAR) stayed relatively steady in the open-coastal mangroves, while they increased exponentially in the estuarine mangroves since 1900. The estuarine mangroves had significantly higher SAR and C, N and P burial rates than the open-coastal mangroves. C, N and P burial rates averaged at 141.52 g m-2 a-1, 6.27 g m-2 a-1 and 1.14 g m-2 a-1, respectively in the estuarine core, and these rates averaged at 61.71 g m-2 a-1, 3.71 g m-2 a-1 and 0.43 g m-2 a-1, respectively in the open-coastal core. The results suggest that estuarine mangroves may be more capable of surviving accelerating sea level rise under climate change and play a greater role in C accumulation and nutrient filtering under anthropogenic nutrient enrichment than marine-dominated mangroves. Blue C burial may be enhanced by coastal water eutrophication, but such a relationship needs to be tested in further studies.


Assuntos
Carbono , Ecossistema , Carbono/análise , Áreas Alagadas , Aquicultura , China , Eutrofização
18.
Water Res ; 250: 121010, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142507

RESUMO

Cylindrospermopsin (CYN) can induce phytoplankton community to secrete alkaline phosphatase (ALP), which is one of the important strategies for the bloom-forming cyanobacterium Raphidiopsis to thrive in extremely low-phosphorus (P) waters. However, how bacterioplankton community, another major contributor to ALPs in waters, couples to Raphidiopsis through CYN, and the role of this coupling in supporting the dominance of Raphidiopsis in nature remain largely unknown. Here, we conducted microcosm experiments to address this knowledge gap, using a combination of differential filtration-based and metagenomics-based methods to identify the sources of ALPs. We found that, compared with algal-derived ALPs, bacteria-derived ALPs exhibited a more pronounced and sensitive response to CYN. This response to CYN was enhanced under low-P conditions. Interestingly, we found that Verrucomicrobia made the largest contribution to the total abundance of pho genes, which encode ALPs. Having high gene abundance of the CYN-sensing PI3K-AKT signaling pathway, Verrucomicrobia's proportion increased with higher concentrations of CYN under low-P conditions, thereby explaining the observed increase in pho gene abundance. Compared with other cyanobacterial genera, Raphidiopsis had a higher abundance of the pst gene. This suggests that Raphidiopsis exhibited a greater capacity to uptake the inorganic P generated by ALPs secreted by other organisms. Overall, our results reveal the mechanism of CYN-induced ALP secretion and its impact on planktonic P-cycling, and provide valuable insights into the role of CYN in supporting the formation of Raphidiopsis blooms.


Assuntos
Alcaloides , Cianobactérias , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinases/metabolismo , Cianobactérias/metabolismo , Toxinas de Cianobactérias , Fósforo/metabolismo , Uracila
19.
Sci Total Environ ; 912: 169234, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38101631

RESUMO

BACKGROUND: Parasitic infections (PIs) are common and pose substantial health hazards in children globally, but the fundamental environmental variables exposure during crucial time window(s) are unclear. OBJECTIVES: To identify key indoor and outdoor environmental factors leading to childhood PIs throughout critical time window(s). METHODS: A combined cross-sectional and retrospective cohort study was performed on 8689 children residing in Changsha, China. Data was acquired pertaining to the health status and environmental exposure of the children in their homes. Personal exposure to outdoor air pollutants at the residential address during the preconceptional, perinatal, and postnatal periods was computed using data from ten air quality monitoring stations. An analysis of the relationships between childhood PIs and both indoor and outdoor factors was conducted using a multiple logistic regression model. RESULTS: Childhood PIs were associated with outdoor CO and ozone (O3) exposure during the 10th-12th months prior to pregnancy, with ORs (95 % CI) of 1.68 (1.24-2.27) and 1.60 (1.15-2.22), respectively; childhood PIs were also associated with CO exposure during one year prior to pregnancy and the first trimester in utero [ORs = 1.57 (1.14-2.15) and 1.52 (1.17-1.97)]. Childhood PIs were found to be associated with PM2.5 exposure during pregnancy and the first year, with odds ratios of 1.51 (1.14-2.00) and 1.95 (1.22-3.12) per IQR increase in pollutant exposure, respectively. Exposures to smoke, renovation-related indoor air pollution (IAP), dampness and plant-related indoor allergens in the early life and past year were all associated with childhood PI, with odds ratios (95 % CI) ranging from 1.40 (1.01-1.95) for environmental tobacco smoke (ETS) during pregnancy to 1.63 (1.12-2.37) for mold/damp stains in the past year. In terms of PI risk, the early life and present periods were critical time windows for outdoor and indoor exposures, respectively. Certain individuals were more vulnerable to the PI risk associated with both indoor and outdoor exposures. Antibiotic use during child's lifetime and early years increased and decreased the PI risk of exposure to outdoor and indoor environments, respectively. CONCLUSIONS: Exposure to outdoor air pollution in early life and indoor environments in the past year were found to be associated with childhood PI.


Assuntos
Poluentes Atmosféricos , Poluição do Ar em Ambientes Fechados , Poluição do Ar , Gravidez , Feminino , Humanos , Criança , Estudos Retrospectivos , Estudos Transversais , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/efeitos adversos , Poluição do Ar em Ambientes Fechados/análise , Exposição Ambiental/análise
20.
Nat Commun ; 14(1): 8196, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38081846

RESUMO

Mangroves and saltmarshes are biogeochemical hotspots storing carbon in sediments and in the ocean following lateral carbon export (outwelling). Coastal seawater pH is modified by both uptake of anthropogenic carbon dioxide and natural biogeochemical processes, e.g., wetland inputs. Here, we investigate how mangroves and saltmarshes influence coastal carbonate chemistry and quantify the contribution of alkalinity and dissolved inorganic carbon (DIC) outwelling to blue carbon budgets. Observations from 45 mangroves and 16 saltmarshes worldwide revealed that >70% of intertidal wetlands export more DIC than alkalinity, potentially decreasing the pH of coastal waters. Porewater-derived DIC outwelling (81 ± 47 mmol m-2 d-1 in mangroves and 57 ± 104 mmol m-2 d-1 in saltmarshes) was the major term in blue carbon budgets. However, substantial amounts of fixed carbon remain unaccounted for. Concurrently, alkalinity outwelling was similar or higher than sediment carbon burial and is therefore a significant but often overlooked carbon sequestration mechanism.

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