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1.
Sci Bull (Beijing) ; 2024 Apr 25.
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.

2.
Sci Total Environ ; 930: 172853, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38685434

RESUMO

Enhancing silicate weathering to increase oceanic alkalinity, thereby facilitating the absorption of atmospheric carbon dioxide (CO2), is considered a highly promising technique for carbon sequestration. This study aims to evaluate the feasibility and potential of olivine-based ocean alkalinity enhancement (OAE) for the removal of atmospheric CO2 and its storage in seawater as bicarbonates in the East and South China Seas (ESCS). A particular focus is placed on the potential ecological impacts arising from the release of nickel (Ni) and chromium (Cr) during the olivine weathering process. We considered two extreme scenarios: one where Ni and Cr are entirely retained in seawater, and another where they are completely deposited in sediments. These scenarios respectively represent the maximum permissible concentrations of Ni and Cr in seawater and sediments during the OAE process. Current marine environmental quality standards (EQS) were utilized as the threshold limits for Ni and Cr in both seawater and sediment, with concentrations exceeding these EQS potentially leading to significant adverse effects on marine life. When all released Ni is retained in seawater, the allowable dosage of olivine varies from 0.05 to 13.7 kg/m2 (depending on olivine particle size, temperature, and water depth); when all released Ni is captured by sediment, the permissible addition of olivine ranges from 0.21 to 2.1 kg/m2 (depending on mixing depth). Given the low solubility of Cr, it is not necessary to consider the scenario where Cr exceeds the limit in seawater. The allowable amount of Cr entirely retained in sediments ranges from 0.69 to 47.2 kg/m2.In most scenarios, the accumulation of metals in sediments preferentially exceeds the corresponding threshold value rather than remaining in seawater. Therefore, we recommend using alkalization equipment to fully dissolve olivine before discharging into the sea, enabling a larger-scale application of olivine without significant negative ecological impacts.

3.
J Agric Food Chem ; 72(13): 7043-7054, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38509000

RESUMO

14-3-3ζ protein, the key target in the regulation and control of integrin ß3 outside-in signaling, is an attractive new strategy to inhibit thrombosis without affecting hemostasis. In this study, 4'-O-methylbavachalconeB (4-O-MB) in Psoraleae Fructus was identified as a 14-3-3ζ ligand with antithrombosis activity by target fishing combined with ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS) analysis. The competitive inhibition analysis showed that 4-O-MB targeted 14-3-3ζ and blocked the 14-3-3ζ/integrin ß3 interaction with inhibition constant (Ki) values of 9.98 ± 0.22 µM. Molecular docking and amino acid mutation experiments confirmed that 4-O-MB specifically bound to 14-3-3ζ through LSY9 and SER28 to regulate the 14-3-3ζ/integrin ß3 interaction. Besides, 4-O-MB affected the integrin ß3 early outside-in signal by inhibiting AKT and c-Src phosphorylation. Meanwhile, 4-O-MB could inhibit ADP-, collagen-, or thrombin-induced platelet aggregation function but had no effect on platelet adhesion to collagen-coated surfaces in vivo. Administration of 4-O-MB could significantly inhibit thrombosis formation without disturbing hemostasis in mice. These findings provide new prospects for the antithrombotic effects of Psoraleae Fructus and the potential application of 4-O-MB as lead compounds in the therapy of thrombosis by targeting 14-3-3ζ.


Assuntos
Agregação Plaquetária , Trombose , Camundongos , Animais , Integrina beta3/genética , Integrina beta3/química , Integrina beta3/metabolismo , Proteínas 14-3-3/genética , Proteínas 14-3-3/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/farmacologia , Simulação de Acoplamento Molecular , Trombose/tratamento farmacológico , Trombose/genética , Trombose/metabolismo , Colágeno/metabolismo , Plaquetas/metabolismo
4.
Nat Rev Microbiol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491185

RESUMO

The ocean has been a regulator of climate change throughout the history of Earth. One key mechanism is the mediation of the carbon reservoir by refractory dissolved organic carbon (RDOC), which can either be stored in the water column for centuries or released back into the atmosphere as CO2 depending on the conditions. The RDOC is produced through a myriad of microbial metabolic and ecological processes known as the microbial carbon pump (MCP). Here, we review recent research advances in processes related to the MCP, including the distribution patterns and molecular composition of RDOC, links between the complexity of RDOC compounds and microbial diversity, MCP-driven carbon cycles across time and space, and responses of the MCP to a changing climate. We identify knowledge gaps and future research directions in the role of the MCP, particularly as a key component in integrated approaches combining the mechanisms of the biological and abiotic carbon pumps for ocean negative carbon emissions.

5.
J Agric Food Chem ; 72(12): 6265-6275, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38487839

RESUMO

Paeonia suffruticosa Andr. is a well-known landscape plant worldwide and also holds significant importance in China due to its medicinal and dietary properties. Previous studies have found that Cortex Moutan (CM), the dried root bark of P. suffruticosa, showed antiplatelet and cardioprotective effects, although the underlying mechanism and active compounds remain to be revealed. In this study, protein disulfide isomerase (PDI) inhibitors in CM were identified using a ligand-fishing method combined with the UHPLC-Q-TOF-MS assay. Further, their binding sites and inhibitory activities toward PDI were validated. The antiplatelet aggregation and antithrombotic activity were investigated. The results showed that two structurally similar compounds in CM were identified as the inhibitor for PDI with IC50 at 3.22 µM and 16.73 µM; among them Mudanpioside C (MC) is the most effective PDI inhibitor. Molecular docking, site-directed mutagenesis, and MST assay unequivocally demonstrated the specific binding of MC to the b'-x domain of PDI (Kd = 3.9 µM), acting as a potent PDI inhibitor by interacting with key amino acids K263, D292, and N298 within the b'-x domain. Meanwhile, MC could dose-dependently suppress collagen-induced platelet aggregation and interfere with platelet activation, adhesion, and spreading. Administration of MC can significantly inhibit thrombosis formation without disturbing hemostasis in mice. These findings present a promising perspective on the antithrombotic properties of CM and highlight the potential application of MC as lead compounds for targeting PDI in thrombosis therapy.


Assuntos
Paeonia , Trombose , Animais , Camundongos , Isomerases de Dissulfetos de Proteínas/química , Isomerases de Dissulfetos de Proteínas/metabolismo , Fibrinolíticos , Simulação de Acoplamento Molecular , Trombose/metabolismo
6.
Small Methods ; : e2301620, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38343178

RESUMO

Acute inflammation has the potential for the recruitment of immune cells, inhibiting tumor angiogenesis, metastasis, and drug resistance thereby overcoming the tumor immunosuppressive microenvironment caused by chronic inflammation. Here, an acute inflammation inducer using bacteria outer membrane vesicles (OMVs) loaded in thermal-sensitive hydrogel (named OMVs-gel) for localized and controlled release of OMVs in tumor sites is proposed. OMVs trigger neutrophil recruitment and amplify acute inflammation inside tumor tissues. The hydrogel ensures drastic inflammation is confined within the tumor, addressing biosafety concerns that the direct administration of free OMVs may cause fatal effects. This strategy eradicated solid tumors safely and rapidly. The study further elucidates one of the possible immune mechanisms of OMVs-gel therapy, which involves the assembly of antitumor neutrophils and elastase release for selective tumor killing. Additionally, tumor vascular destruction induced by OMVs-gel results in tumor darkening, allowing for combinational photothermal therapy. The findings suggest that the use of OMVs-gel can safely induce acute inflammation and enhance antitumor immunity, representing a promising strategy to promote acute inflammation application in tumor immunotherapy.

7.
Front Microbiol ; 15: 1345952, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38343717

RESUMO

Viruses are infectious and abundant in the marine environment. Viral lysis of host cells releases organic matter and nutrients that affect the surrounding microbial community. Synechococcus are important primary producers in the ocean and they are subject to frequent viral infection. In the laboratory, Synechococcus cultures are often associated with bacteria and such a co-existence relationship appears to be important to the growth and stability of Synechococcus. However, we know little about how viral lysis of Synechococcus affects the co-existing bacteria in the culture. This study investigated the influence of viral infection of Synechococcus on co-occurring bacterial community in the culture. We analyzed the community composition, diversity, predicted functions of the bacterial community, and its correlations with fluorescent dissolved organic matter (FDOM) components and nutrients after introducing a cyanophage to the Synechococcus culture. Cyanophage infection altered the bacterial community structure and increased the bacterial diversity and richness. Increased bacterial groups such as Bacteroidetes and Alphaproteobacteria and decreased bacterial groups such as Gammaproteobacteria were observed. Moreover, cyanophage infection reduced bacterial interactions but enhanced correlations between the dominant bacterial taxa and nutrients. Unique FDOM components were observed in the cyanophage-added culture. Fluorescence intensities of FDOM components varied across the cyanophage-infection process. Decreased nitrate and increased ammonium and phosphate in the cyanophage-added culture coupled with the viral progeny production and increased substance transport and metabolism potentials of the bacterial community. Furthermore, increased potentials in methane metabolism and aromatic compound degradation of the bacterial community were observed in the cyanophage-added culture, suggesting that cyanophage infections contribute to the production of methane-related compounds and refractory organic matter in a microcosm like environment. This study has the potential to deepen our understanding of the impact of viral lysis of cyanobacteria on microbial community in the surrounding water.

8.
J Cancer ; 15(4): 1041-1052, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38230224

RESUMO

Background: Dopamine receptors have been reported to be involved in pain, while the exact effects and mechanism in bone cancer pain have not been fully explored. Methods: Bone cancer pain model was created by implanting walker 256 mammary gland carcinoma into right tibia bone cavity. Primary cultured spinal neurons were used for in vitro evaluation. FLIPR, western-blot, immunofluorescence, and Co-IP were used to detect cell signaling pathway. Results: Our results indicated that spinal dopamine D1 receptor (D1DR) and spinal dopamine D2 receptor (D2DR) could form heteromers in TCI rats, and antagonizing spinal D1DR and D2DR reduced heteromers formation and alleviated TCI-induced bone cancer pain. Further results indicated that D1DR or D2DR antagonist induced antinociception in TCI rats could be reversed by D1DR, D2DR, and D1/D2DR heteromer agonists. And Gq, IP3, and PLC inhibitors also attenuated TCI-induced bone cancer pain. In vitro results indicated that D1DR or D2DR antagonist decreased the Ca2+ oscillations upregulated by D1DR, D2DR, and D1/D2DR heteromer agonists in activated primary cultured spinal neurons. Moreover, inhibition of D1/D2DR heteromers induced antinociception in TCI rats was partially mediated by the CaMKII and MAPKs pathway. In addition, a natural compound levo-Corydalmine (l-CDL), could inhibit D1/D2DR heteromers and attenuate bone cancer pain. Results: Inhibition of spinal D1/D2DR heteromers via l-CDL decreases excitability in spinal neurons, which might present new therapeutic strategy for bone cancer pain.

9.
J Pharm Biomed Anal ; 240: 115939, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38198887

RESUMO

The purpose of this study is to screen a novel Rg2 derivative for anti hemorrhagic shock. Eight Rg2 amino acid ester derivatives were designed and synthesized, and their effects on hypoxia and shock were studied. Among them, the derivative 1 (D1) exhibited excellent anti hypoxia by promoting survival rate of H9c2 cells damaged by hypoxia. D1 improved physiological indicators of the rats in hemorrhagic shock, such as blood pressure, heart rate, lactate, acid-base balance, and alleviate oxidative stress and inflammatory damage. Its latent mechanisms were explored by a method of plasma metabolomics based on UPLC-QTOF-MS. As a result, a total of 16 biomarkers were identified involving 6 metabolic pathways. The results of this study contained that the derivative 1 could be considered as potent drug candidates for anti shock and deserved further research and development.


Assuntos
Ginsenosídeos , Choque Hemorrágico , Ratos , Animais , Ginsenosídeos/farmacologia , Ginsenosídeos/uso terapêutico , Choque Hemorrágico/tratamento farmacológico , Estresse Oxidativo , Aminoácidos , Hipóxia
10.
Luminescence ; 39(1): e4610, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37880919

RESUMO

Construction of fluorescent probes for zinc ion (Zn2+ ) and cadmium ion (Cd2+ ) is significant for the safety of humans. However, the discriminating recognition of Zn2+ and Cd2+ by a single probe remains challenging owing to their similar properties. Herein, a novel deoxycholic acid derivative containing 8-hydroxyquinoline fluorophore has been facilely synthesized through click chemistry to form a clamp-like probe. Using its perfect bonding cavity from 1,2,3-triazole and quinoline, this molecule showed favorable solvent-dependent fluorescent responses and distinguished Zn2+ and Cd2+ in different solvents. In ethanol aqueous solution, it displayed good selectivity and ratiometric fluorescence to Zn2+ with 30 nm spectroscopic red-shifts. In acetonitrile aqueous solution, it exhibited good selectivity and ratiometric fluorescence to Cd2+ with 18 nm spectroscopic red-shifts. Moreover, the unique microstructural features of the probe in assembly were used to reflect its recognition processes. Due to its merits of low detection limit and instant response time, the probe was utilized for sensing Zn2+ and Cd2+ in water, beer and urine with high accuracy. Meanwhile, this probe served as a handy tool and was employed to obtain inexpensive test strips for the prompt and semiqualitative analysis of Zn2+ and Cd2+ with the naked eye.


Assuntos
Corantes Fluorescentes , Zinco , Humanos , Solventes , Zinco/química , Corantes Fluorescentes/química , Cádmio/análise , Química Click , Oxiquinolina , Água/química , Espectrometria de Fluorescência
11.
Front Microbiol ; 14: 1293846, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029084

RESUMO

Cyanophages affect the abundance, diversity, metabolism, and evolution of picocyanobacteria in marine ecosystems. Here we report an estuarine Synechococcus phage, S-CREM2, which represents a novel viral genus and leads to the establishment of a new T4-like cyanophage clade named cluster C. S-CREM2 possesses the longest tail (~418 nm) among isolated cyanomyoviruses and encodes six tail-related proteins that are exclusively homologous to those predicted in the cluster C cyanophages. Furthermore, S-CREM2 may carry three regulatory proteins in the virion, which may play a crucial role in optimizing the host intracellular environment for viral replication at the initial stage of infection. The cluster C cyanophages lack auxiliary metabolic genes (AMGs) that are commonly found in cyanophages of the T4-like clusters A and B and encode unique AMGs like an S-type phycobilin lyase gene. A variation in the composition of tRNA and cis-regulatory RNA genes was observed between the marine and freshwater phage strains in cluster C, reflecting their different modes of coping with hosts and habitats. The cluster C cyanophages are widespread in estuarine and coastal regions and exhibit equivalent or even higher relative abundance compared to those of clusters A and B cyanophages in certain estuarine regions. The isolation of cyanophage S-CREM2 provides new insights into the phage-host interactions mediated by both newly discovered AMGs and virion-associated proteins and emphasizes the ecological significance of cluster C cyanophages in estuarine environments.

12.
Demography ; 60(6): 1649-1664, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37942709

RESUMO

This research note reinvestigates Abdellaoui et al.'s (2019) findings that genetically selective migration may lead to persistent and accumulating socioeconomic and health inequalities between types (coal mining or non-coal mining) of places in the United Kingdom. Their migration measure classified migrants who moved to the same type of place (coal mining to coal mining or non-coal mining to non-coal mining) into "stay" categories, preventing them from distinguishing migrants from nonmigrants. We reinvestigate the question of genetically selective migration by examining migration patterns between places rather than place types and find genetic selectivity in whether people migrate and where. For example, we find evidence of positive selection: people with genetic variants correlated with better education moved from non-coal mining to coal mining places with our measure of migration. Such findings were obscured in earlier work that could not distinguish nonmigrants from migrants.


Assuntos
Migrantes , Humanos , Reino Unido , Escolaridade
13.
Demography ; 60(6): 1631-1648, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37937916

RESUMO

Migration is selective, resulting in inequalities between migrants and nonmigrants. However, investigating migration selection is empirically challenging because combined pre- and post-migration data are rarely available. We propose an alternative approach to assessing internal migration selection by integrating genetic data, enabling an investigation of migration selection with cross-sectional data collected post-migration. Using data from the UK Biobank, we utilized standard tools from statistical genetics to conduct a genome-wide association study (GWAS) for migration distance. We then calculated genetic correlations to compare GWAS results for migration with those for other characteristics. Given that individual genetics are determined at conception, these analyses allow a unique exploration of the association between pre-migration characteristics and migration. Results are generally consistent with the healthy migrant literature: genetics correlated with longer migration distance are associated with higher socioeconomic status and better health. We also extended the analysis to 53 traits and found novel correlations between migration and several physical health, mental health, personality, and sociodemographic traits.


Assuntos
Emigração e Imigração , Migrantes , Humanos , Estudos Transversais , Estudo de Associação Genômica Ampla , Classe Social
14.
Mar Pollut Bull ; 196: 115620, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37804671

RESUMO

In this study, the sources of nine heavy metals (Cd, As, Hg, Cu, Pb, Ni, Cr, Zn, and Co) in the sediments of the Bohai Sea were quantitatively identified through a positive factor matrix to provide better advice for marine and coastal management. In Bohai Sea sediments, most metals fell below detectable contamination levels, including As, Cu, Pb, Ni, Cr, Zn, and Co. Unfortunately, Bohai Sea sediments were moderately to significantly enrich with Cd and Hg, posing potentially adverse ecological risks to aquatic ecosystems. Our modeled results showed three factors representing natural, anthropogenic, and atmospheric deposition sources. Enriched Cd and Hg were likely derived from anthropogenic activities through river runoff and atmospheric deposition due to adjacent Zn smelting and chlor-alkali production, respectively. The other metals were mainly derived from natural sources.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Ecossistema , Sedimentos Geológicos , Cádmio , Chumbo , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , China , Medição de Risco
15.
Animals (Basel) ; 13(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37835722

RESUMO

The feeding relationship between copepods and phytoplankton has immense ecological significance. This study investigated the feeding behavior of copepods by studying the feeding selectivity of Paracalanus parvus, a key small copepod species, using a high-speed camera. The feeding behavior of P. parvus separately fed on three algae, Prorocentrum minimum, Alexandrium minutum, and Thalassiosira weissflogii, was studied at five different concentrations. The factors characterizing feeding behavior, including the beating frequency (BF), beating time (BT), and rejection behavior, were analyzed. The average BT and BF of P. parvus fed on toxic algae were significantly lower than those of copepods fed on nontoxic algae, indicating that the toxic algae negatively affected their feeding behavior. There were no significant differences in feed rejection among the three algae during the short period of experimentation, indicating that the rejection behavior was insignificant in the early period (within 20 min) of feeding on toxic algae. The feeding behavior was inhibited when the concentration reached 250 cells/mL. The BT was initially affected at increasing concentrations followed by the BF, and P. minimum and A. minutum reduced the BF at concentrations of 250 and 1000 cells/mL, respectively. Analysis of the average BFs revealed that P. parvus was more significantly affected by P. minimum containing diarrheal shellfish poison than by A. minutum containing paralytic shellfish poison. The BF of copepods fed on P. minimum was significantly lower than that of copepods fed on A. minutum at 250-500 cells/mL but was not significantly different from that at 1000 cells/mL. This indicated that the inhibitory effect of P. minimum on the feeding behavior was more significant at concentrations observed at the onset of red tide blooms (0.25-0.5 × 102 cells/mL), but insignificant at concentrations reaching those in advanced red tides (>103 cells/mL). This study demonstrates that toxic dinoflagellates alter the feeding behavior of copepods and describes the variations in their feeding response to different algal species and concentrations. The findings provide crucial insights for further studies on the feeding relationship between copepods and phytoplankton and on functional assessment of plankton ecosystems.

16.
Int J Mol Sci ; 24(20)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37894895

RESUMO

Tetrahydroprotoberberines (THPBs) are plant-specific alkaloids with significant medicinal value. They are present in trace amounts in plants and are difficult to chemically synthesize due to stereoselectivity and an unfavorable environment. In this study, a selective methylation strategy was developed for the biocatalysis of seven high-value-added THPB compounds using 4'-O-methyltransferase (Cj4'OMT), norcoclaurine 6-O-methyltransferase (Cj6OMT), and (S)-scoulerine 9-O-methyltransferase (SiSOMT and PsSOMT) in engineered E. coli. The methyltransferases Cj4'OMT, Cj6OMT, PsSOMT, and SiSOMT were expressed heterologously in E. coli. Compound 1 (10-methoxy-2,3,9-tetrahydroxyberbine) was synthesized using the recombinant E. coli strain Cj4'OMT and the substrate 2,3,9,10-tetrahydroxyberbine. Compound 2 (9-methoxy-2,3,10-tetrahydroxyberbine) was produced in the recombinant Escherichia coli (E. coli) strain PsSOMT, and compounds 2 and 3 (discretamine) were produced in the recombinant E. coli strain SiSOMT. Compounds 4 (9,10-methoxy-2,3-tetrahydroxyberbine) and 5 (corypalmine) were obtained by co-culturing the recombinant strains Cj4'OMT and SiSOMT with substrate. Compounds 6 (scoulerine) and 7 (isoscoulerine) were produced by co-culturing the substrate with the recombinant strains Cj4'OMT and Cj6OMT. To increase the yield of novel compound 2, the flask culture conditions of the engineered SiSOMT strain were optimized, resulting in the production of 165.74 mg/L of this compound. This study thus presents an enzymatic approach to the synthesis of high-value-added THPBs with minimum environmental wastage.


Assuntos
Alcaloides , Escherichia coli , Metilação , Escherichia coli/genética , Escherichia coli/metabolismo , Metiltransferases/metabolismo , Processamento de Proteína Pós-Traducional
17.
Sci Rep ; 13(1): 15298, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37714930

RESUMO

To explore the pathogenesis of Bell's palsy using the diffusion tensor image on 3.0 T MR. The healthy people and the patients with Bell's palsy underwent intraparotid facial nerve scanning by using the DTI and T1 structural sequence at 3.0 T MR. The raw DTI data were performed affine transformation and nonlinear registration in the common MNI152_T1 space and resampled to the 0.4 mm3 voxel size. A group of 4 spherical seed regions were placed on the intratemporal facial nerves in the common space, bilaterally and symmetrically. The DTI data in the common space were used to track the intratemporal facial nerve fibers by using TrackVis and its Diffusion Toolkit. Each tractography was used to construct the maximum probability map (MPM) according to the majority rule. The fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) were calculated and extracted on the basis of MPM. For healthy people, there was no significant difference in FA, MD, RD and AD of bilateral facial nerves. For patients with Bell's palsy, there was no significant difference in AD, there was significant difference in FA, MD and RD between the affected nerve and the healthy nerve (P < 0.02). This study showed that the myelin sheath injury of the intratemporal facial nerve is the main cause of Bell's palsy. Most neural axons are not damaged. The results may explain the pathogenesis of the Bell's palsy, which is self-limited for most cases.


Assuntos
Paralisia de Bell , Paralisia Facial , Humanos , Paralisia de Bell/diagnóstico por imagem , Nervo Facial/diagnóstico por imagem , Anisotropia , Axônios
18.
Innovation (Camb) ; 4(5): 100481, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37636281

RESUMO

To achieve the Paris Agreement, China pledged to become "Carbon Neutral" by the 2060s. In addition to massive decarbonization, this would require significant changes in ecosystems toward negative CO2 emissions. The ability of coastal blue carbon ecosystems (BCEs), including mangrove, salt marsh, and seagrass meadows, to sequester large amounts of CO2 makes their conservation and restoration an important "nature-based solution (NbS)" for climate adaptation and mitigation. In this review, we examine how BCEs in China can contribute to climate mitigation. On the national scale, the BCEs in China store up to 118 Tg C across a total area of 1,440,377 ha, including over 75% as unvegetated tidal flats. The annual sedimental C burial of these BCEs reaches up to 2.06 Tg C year-1, of which most occurs in salt marshes and tidal flats. The lateral C flux of mangroves and salt marshes contributes to 1.17 Tg C year-1 along the Chinese coastline. Conservation and restoration of BCEs benefit climate change mitigation and provide other ecological services with a value of $32,000 ha-1 year-1. The potential practices and technologies that can be implemented in China to improve BCE C sequestration, including their constraints and feasibility, are also outlined. Future directions are suggested to improve blue carbon estimates on aerial extent, carbon stocks, sequestration, and mitigation potential. Restoring and preserving BCEs would be a cost-effective step to achieve Carbon Neutral by 2060 in China despite various barriers that should be removed.

19.
Sci Total Environ ; 893: 164835, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37321495

RESUMO

Dissolved organic matter (DOM) in natural ecosystems is intimately associated with microbial communities. However, it remains unclear whether the diversity patterns followed by microbes can be transmitted to DOM compounds. Considering the structural properties of DOM compounds and the roles of microbes in ecosystems, we hypothesized that bacteria tended to be more closely associated with DOM compounds than fungi. To test the above hypothesis and bridge this knowledge gap, the diversity patterns and ecological processes for the DOM compounds, and the bacterial and fungal communities in a mudflat intertidal zone were comparatively investigated. As a result, spatial scaling patterns followed by microbes, including the diversity-area and distance-decay relationships, were also observed for DOM compounds. Lipid-like and aliphatic-like molecules comprised the major DOM compounds associated with environmental factors. Both the alpha- and beta-chemodiversity of DOM compounds were significantly associated with the diversity of bacterial communities, but not fungal communities. Co-occurrence ecological network analysis suggested that DOM compounds were more frequently associated with bacteria than fungi. Further, consistent community assembly patterns were observed for DOM and bacterial communities, but not fungal communities. Integrating multiple lines of evidence, this study demonstrated that bacteria rather than fungi mediated the chemodiversity of DOM in the mudflat intertidal zone. This study elucidates the spatial patterns of complex dissolved organic matter (DOM) pools in the intertidal ecosystem, shedding light on the intricate relationship between DOM compounds and bacterial communities.


Assuntos
Matéria Orgânica Dissolvida , Microbiota , Carbono/química , Bactérias , Fungos
20.
Sci Data ; 10(1): 205, 2023 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-37055424

RESUMO

Utilisation of dissolved organic phosphorus (DOP) by marine microbes as an alternative phosphorus (P) source when phosphate is scarce can help sustain non-Redfieldian carbon:nitrogen:phosphorus ratios and efficient ocean carbon export. However, global spatial patterns and rates of microbial DOP utilisation are poorly investigated. Alkaline phosphatase (AP) is an important enzyme group that facilitates the remineralisation of DOP to phosphate and thus its activity is a good proxy for DOP-utilisation, particularly in P-stressed regions. We present a Global Alkaline Phosphatase Activity Dataset (GAPAD) with 4083 measurements collected from 79 published manuscripts and one database. Measurements are organised into four groups based on substrate and further subdivided into seven size fractions based on filtration pore size. The dataset is globally distributed and covers major oceanic regions, with most measurements collected in the upper 20 m of low-latitude oceanic regions during summer since 1997. This dataset can help support future studies assessing global ocean P supply from DOP utilisation and provide a useful data reference for both field investigations and modelling activities.

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