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1.
BMC Geriatr ; 24(1): 825, 2024 Oct 12.
Article de Anglais | MEDLINE | ID: mdl-39395950

RÉSUMÉ

BACKGROUND: The increasing prevalence of cognitive impairment poses substantial risks to older adults, particularly those with chronic diseases. While existing studies have examined the connection between the empty nest phenomenon and cognitive function, few have attempted to consider endogeneity issues within this relationship, with limited attention given to older adults with chronic diseases. This study investigates the impact of empty nest status on cognitive function among rural Chinese older adults with chronic diseases and explores the possible mechanisms underlying this effect. METHODS: A cross-sectional study involved 365 older adults aged 60 or above with chronic diseases in rural areas of Shaanxi province, northwest China. Cognitive function was measured using the Mini-Mental State Examination. Multiple regression models and the instrumental variable (IV) method were employed to examine the association between empty nest and cognitive function. RESULTS: Among the 365 older adults aged 60 or above with chronic diseases, 43% experienced cognitive impairment. Results from both multiple regression and IV analyses consistently demonstrate a significant association between empty nest status and higher cognitive function scores (ß = 1.757, p = 0.007; ß = 3.682, p = 0.034, respectively). Mechanism analysis further supports that the positive association may arise from empty nesters receiving more social support from children and friends, and perceiving loneliness experiences as inadequate. Heterogeneity analysis reveals that the association between empty nest status and cognitive function is more pronounced among male adults with chronic diseases. CONCLUSIONS: This study challenges the notion that empty nest status is a risk factor for cognitive decline in older adults with chronic diseases in rural China. The positive impact is attributed to the robust social relationships of empty nesters, encompassing sustained support from their social network, and the absence of an increase in loneliness. Therefore, future interventions aimed at improving cognitive function in older adults may benefit from promoting the development of social relationships.


Sujet(s)
Cognition , Dysfonctionnement cognitif , Population rurale , Humains , Mâle , Femelle , Chine/épidémiologie , Sujet âgé , Études transversales , Maladie chronique/épidémiologie , Adulte d'âge moyen , Dysfonctionnement cognitif/épidémiologie , Dysfonctionnement cognitif/psychologie , Dysfonctionnement cognitif/diagnostic , Cognition/physiologie , Sujet âgé de 80 ans ou plus , Soutien social , Solitude/psychologie
2.
Inorg Chem ; 63(38): 17864-17871, 2024 Sep 23.
Article de Anglais | MEDLINE | ID: mdl-39255341

RÉSUMÉ

Advances in materials science are increasingly dependent on the development of multifunctional materials capable of improving system efficiency and reducing the environmental impact. In this study, two zero-dimensional (0D) cadmium-based organic-inorganic hybrid materials (BEMPD)2CdBr4 (BEMPD-Br, 1) and (BEMPD)2CdBr2Cl2 (BEMPD-ClBr, 2) (BEMPD = 1-(2-bromoethyl)-1-methylpiperidine) were prepared by halogen doping. Compound 2 is a mixed halide in which there are two halogen sites, Cl and Br, and in a disordered state, which has a regulatory effect on the structural distortion and properties of the compound. The Curie temperatures of compounds 1 and 2 are 348 and 390 K, respectively, and the UV-vis absorption spectra showed that the direct band gaps of compounds 1 and 2 were 4.68 and 4.8 eV, respectively. In addition, room-temperature photoluminescence experiments show broadband emission peaks at 717 and 683 nm for compounds 1 and 2, respectively, with fluorescence lifetimes of 2.414 and 3.915 µs. These 0D hybrids provide an avenue for the development of smart materials and optoelectronic devices, and also provide positive clues for manipulating the properties of organic-inorganic hybrid compounds.

4.
Inorg Chem ; 63(7): 3411-3417, 2024 Feb 19.
Article de Anglais | MEDLINE | ID: mdl-38311915

RÉSUMÉ

In the past decade, metal halide materials have been favored by many researchers because of their excellent physical and chemical properties under thermal, electrical, and light stimuli, such as ferroelectricity, dielectric, nonlinearity, fluorescence, and semiconductors, greatly promoting their application in optoelectronic devices. In this study, we successfully constructed an unleaded organic-inorganic hybrid perovskite crystal: [Cl-C6H4-(CH2)2NH3]3SbBr6 (1), which underwent a high-temperature reversible phase transition near Tp = 368 K. The phase transition behavior of 1 was characterized by differential scanning calorimetry, accompanied by a thermal hysteresis of 6 K. In addition, variable-temperature Raman spectroscopy analysis and PXRD further verified the sensitivity of 1 to temperature and the phase transition from low symmetry to high symmetry. Temperature-dependent dielectric testing shows that 1 can be a sensitive switching dielectric constant switching material. Remarkably, 1 exhibits strong photoluminescence emission with a wavelength of 478 nm and a narrow band gap of 2.7 eV in semiconductors. As the temperature increases and decreases, fluorescence undergoes significant changes, especially near Tc, which further confirms the reversible phase transition of 1. All of these findings provide new avenues for designing and assembling new phase change materials with high Tp and photoluminescence properties.

5.
BMC Public Health ; 24(1): 89, 2024 01 04.
Article de Anglais | MEDLINE | ID: mdl-38178047

RÉSUMÉ

BACKGROUND: Amid the COVID-19 pandemic, the significance of vaccination has been emphatically underscored. As the foremost and pivotal measure for preventing COVID-19 transmission, the COVID-19 pneumonia vaccine plays an instrumental role in the global response to this infectious respiratory disease. However, COVID-19 vaccination coverage remains challenging in low- and middle-income countries and regions. Studies have found that frequent seeking to health information is also associated with healthier behaviors, but these studies have not yet focused on the impact of Internet health information seeking on individual vaccination and the mechanism of this effect. METHODS: Data were obtained from the Chinese General Social Survey (CGSS) conducted in 2021, which included 7,218 individual samples. This study used COVID-19 vaccination as indicators for the health of interest, the key independent variable is Internet health information seeking. This study tried to analyze the impact of Internet health information seeking on COVID-19 vaccination using an OLS model and PSM method. RESULTS: The results show that Internet health information seeking has a significant positive impact on COVID-19 vaccination. This result passed a series of robustness tests. The mechanism analysis indicated that compared to non-Internet health information seeking individuals, Internet health information seeking individuals could know the superior advantages of vaccination and the potential for immunization through this method. And individuals who use Internet to seeking health information are more likely to acknowledge the constructive impact of online information on health behavior. This helps to explain why Internet health information seeking individuals have a higher rate of COVID-19 vaccination. CONCLUSIONS: This study delves into the influence of Internet health information seeking on individual COVID-19 vaccination within the digital era. The outcomes underscore that Internet-mediated seeking vaccine information holds the potential to bolster individuals' comprehension of vaccination benefits and foster increased acceptance of such information.


Sujet(s)
COVID-19 , Vaccins , Humains , COVID-19/épidémiologie , COVID-19/prévention et contrôle , Vaccins contre la COVID-19 , Comportement de recherche d'information , Pandémies/prévention et contrôle , Comportement en matière de santé , Vaccination , Internet , Chine/épidémiologie
6.
Epidemiol Infect ; 151: e174, 2023 09 07.
Article de Anglais | MEDLINE | ID: mdl-37675640

RÉSUMÉ

Rodents and shrews are major reservoirs of various pathogens that are related to zoonotic infectious diseases. The purpose of this study was to investigate co-infections of zoonotic pathogens in rodents and shrews trapped in four provinces of China. We sampled different rodent and shrew communities within and around human settlements in four provinces of China and characterised several important zoonotic viral, bacterial, and parasitic pathogens by PCR methods and phylogenetic analysis. A total of 864 rodents and shrews belonging to 24 and 13 species from RODENTIA and EULIPOTYPHLA orders were captured, respectively. For viral pathogens, two species of hantavirus (Hantaan orthohantavirus and Caobang orthohantavirus) were identified in 3.47% of rodents and shrews. The overall prevalence of Bartonella spp., Anaplasmataceae, Babesia spp., Leptospira spp., Spotted fever group Rickettsiae, Borrelia spp., and Coxiella burnetii were 31.25%, 8.91%, 4.17%, 3.94%, 3.59%, 3.47%, and 0.58%, respectively. Furthermore, the highest co-infection status of three pathogens was observed among Bartonella spp., Leptospira spp., and Anaplasmataceae with a co-infection rate of 0.46%. Our results suggested that species distribution and co-infections of zoonotic pathogens were prevalent in rodents and shrews, highlighting the necessity of active surveillance for zoonotic pathogens in wild mammals in wider regions.


Sujet(s)
Bartonella , Co-infection , Leptospira , Animaux , Bartonella/génétique , Chine/épidémiologie , Phylogenèse , Rodentia/microbiologie , Musaraignes/microbiologie
7.
Sci Total Environ ; 904: 166653, 2023 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-37673243

RÉSUMÉ

With the increased construction of dam reservoirs and the demand for water security, terrestrial dissolved organic matter (DOM) has received attention because of its role in regulating water quality, ecological functions, and the fate and transport of pollutants in dam reservoirs. This study investigated the transformations of soil DOM and vegetation DOM of dam reservoirs following photodegradation and biodegradation before conservative mixing, as well as the resultant effects on phenanthrene binding. Based on the results, terrestrial DOM could undergo transformation via photodegradation and biodegradation before conservative mixing in dam reservoirs. Although both processes resulted in substantial decreases in DOM concentrations, the changes in chromophoric DOM and fluorescent DOM depended on the original DOM sources. Furthermore, the photodegradation of terrestrial DOM resulted in more pronounced photobleaching than photomineralization. In addition, photodegradation of terrestrial DOM resulted in the generation of DOM-derived by-products with low molecular weight and low aromaticity, whereas the biodegradation of terrestrial DOM resulted in DOM-derived by-products with low molecular weight and high aromaticity. Subsequently, the photodegradation and biodegradation of terrestrial DOM substantially enhanced the binding affinity of phenanthrene. Soil DOM is prior to vegetation DOM when predicting the ecological risk of HOCs. These results indicate that the terrestrial DOM in dam reservoirs should be reconsidered before conservative mixing. Further studies on the coupling effects of both biogeochemical processes, as well as on the relative contributions of soil DOM and vegetation DOM after transformation to the aquatic DOM in dam reservoirs, are required. This study provides information on the environmental effects of dam construction from the perspective of biogeochemical processes.


Sujet(s)
Matière organique dissoute , Qualité de l'eau , Photolyse , Sol/composition chimique , Dépollution biologique de l'environnement
8.
Dev Cell ; 58(18): 1657-1669.e5, 2023 09 25.
Article de Anglais | MEDLINE | ID: mdl-37480843

RÉSUMÉ

Salt stress is one of the unfavorable environmental factors to affect plants. Salinity represses root growth, resulting in reduced biomass of agricultural plants. Little is known about how plants maintain root growth to counteract salt stress. The AP2-domain transcription factors PLETHORA1/2 (PLT1/2) act as master regulators in root meristem maintenance in Arabidopsis. In this study, we report that the salt overly sensitive (SOS) pathway component SOS2 regulates PLT1/2 at the post-transcriptional level. Salt-activated SOS2 interacts and phosphorylates PLT1/2 through their conserved C-terminal motifs to stabilize PLT1/2, critical for root apical meristem maintenance under salt stress. The phospho-mimetic version of PLT1/2 restored meristem and primary root length reduction of sos2-2 and plt1-4 plt2-2 mutants on salt treatment. Moreover, SOS2-mediated PLT1/2 phosphorylation improves root growth recovery after salt stress alleviation. We identify a SOS2-PLT1/2 core protein module that is required for protecting primary root growth and meristem maintenance from salt stress.


Sujet(s)
Arabidopsis , Méristème , Transduction du signal , Arabidopsis/génétique , Phosphorylation , Stress salin
9.
Sci Total Environ ; 854: 158640, 2023 Jan 01.
Article de Anglais | MEDLINE | ID: mdl-36113805

RÉSUMÉ

Multiple pesticides are heavily applied in crops grown in China's tropics due to the prevalence of diseases and pests, thus posing potential risks to nontarget organisms (e.g., honeybees, lacewings, ladybugs, and humans). However, there is little information on this topic. This study is the first assessment of the occurrence, driving factors, and ecological/human health risks of 32 current-use pesticides (CUPs) in 10 frequently-planted crops collected from practicing rice-vegetable rotation systems in Hainan, China. Of the 132 whole crop samples, 44 (33.3 %) residues from ≥8 pesticides were detected in 9.09 % of crop samples with concentrations ≥0.5 mg kg-1. Six pesticide residues, namely carbendazim, pyraclostrobin, acetamiprid, thiophanate methyl, phoxim, and imidacloprid, were detected in 72.7 % of samples, with concentrations ranging from 0.0021 to 13.5 (median = 0.032) mg kg-1. Among them, carbendazim, pyraclostrobin, and acetamiprid were the most common, contributions from 10.2 to 25.5 % and a detection frequency ranging from 25.6 to 56.1 %. The order of total concentration of 32 CUPs (∑32 CUP) concentrations during the year was January > May > November > August and vegetables > rice, being highly related with pesticides usage pattern, crop type, plant accumulation/dissipation and plant lipid contents. The ecological risk quotients (RQs) to four beneficial terrestrial organisms showed that 9.6-39.1 % of samples posed a potential medium or high ecological risk, with 13.6-65.9 % of samples at ∑RQ > 1 being highly affected by the residues of neonicotinoids and emamectin benzoate. Emamectin benzoate (8.9 %) and acetamiprid (5.6 %) exceeded the individual Maximum Residue Levels based on Chinese legislation (GB2763-2021). Moreover, cumulative dietary exposure presented a higher risk to humans in 11.0 and 22.0 % of the cases for acute and chronic, mainly originating from the higher concentration contributors of systemic pesticides in edible crops. Therefore, the regulation and monitoring of CUP residues is imperative for rice-vegetable rotation systems in tropical China to avoid negative effects on nontarget organisms.


Sujet(s)
Résidus de pesticides , Pesticides , Humains , Animaux , Abeilles , Pesticides/analyse , Contamination des aliments/analyse , Résidus de pesticides/analyse , Produits agricoles , Légumes/composition chimique , Chine , Appréciation des risques
10.
Cluster Comput ; : 1-16, 2022 Oct 28.
Article de Anglais | MEDLINE | ID: mdl-36320212

RÉSUMÉ

Data sharing is very important for medical researchers to do research on certain diseases in cloud-assisted electronic medical systems. Nonetheless, there are large amounts of duplicate data in shared electronic medical records, which incurs redundant storage. In addition, data sharing of electronic medical records might expose the sensitive information of patients. In order to address above problems, we propose a secure data sharing scheme with data deduplication and sensitive information hiding in cloud-assisted electronic medical systems in this paper. In order to protect the sensitive information privacy and enhance the deduplication efficiency, we replace the patient's sensitive information of electronic medical records by wildcards before encrypting the whole electronic medical records. The authorized researcher can decrypt and obtain the electronic medical records under the condition that the sensitive information of shared electronic medical records is hidden. Moreover, we clarify the diagnose information of the electronic medical records into different types according to the duplicate ratio. The authorized researchers can selectively download data according to the duplicate ratio of diagnostic information. Our proposed scheme can resist brute-force attacks and single-point-of-failure attack. The experimental results show our proposed scheme is more efficient than the existing schemes.

12.
Anal Cell Pathol (Amst) ; 2022: 2843990, 2022.
Article de Anglais | MEDLINE | ID: mdl-35942174

RÉSUMÉ

Objective: Glioblastoma is one of the most common malignant tumors in the brain, and these glioblastoma patients have very poor prognosis. Ferroptosis is involved in the progression of various tumors, including the glioblastoma. This study aims to determine the involvement of microRNA (miR)-147a in regulating ferroptosis of glioblastoma in vitro. Methods: Human glioblastoma cell lines were transfected with the inhibitor, mimic and matched negative controls of miR-147a in the presence or absence of ferroptotic inducers. To knock down the endogenous solute carrier family 40 member 1 (SLC40A1), cells were transfected with the small interfering RNA against SLC40A1. In addition, cells with or without the miR-147a mimic treatment were also incubated with temozolomide (TMZ) to investigate whether miR-147a overexpression could sensitize human glioblastoma cells to TMZ chemotherapy in vitro. Results: We found that miR-147a level was decreased in human glioblastoma tissues and cell lines and that the miR-147a mimic significantly suppressed the growth of glioblastoma cells in vitro. In addition, miR-147a expression was elevated in human glioblastoma cells upon erastin or RSL3 stimulation. Treatment with the miR-147a mimic significantly induced ferroptosis of glioblastoma cells, and the ferroptotic inhibitors could block the miR-147a mimic-mediated tumor suppression in vitro. Conversely, the miR-147a inhibitor prevented erastin- or RSL3-induced ferroptosis and increased the viability of glioblastoma cells in vitro. Mechanistically, we determined that miR-147a directly bound to the 3'-untranslated region of SLC40A1 and inhibited SLC40A1-mediated iron export, thereby facilitating iron overload, lipid peroxidation, and ferroptosis. Furthermore, miR-147a mimic-treated human glioblastoma cells exhibited higher sensitivity to TMZ chemotherapy than those treated with the mimic control in vitro. Conclusion: We for the first time determine that miR-147a targets SLC40A1 to induce ferroptosis in human glioblastoma in vitro.


Sujet(s)
Transporteurs de cations/métabolisme , Ferroptose , Glioblastome , microARN , Lignée cellulaire tumorale , Ferroptose/génétique , Glioblastome/génétique , Glioblastome/anatomopathologie , Humains , microARN/génétique , microARN/métabolisme , Témozolomide/pharmacologie , Témozolomide/usage thérapeutique
13.
Plant Signal Behav ; : 2092346, 2022 Jun 26.
Article de Anglais | MEDLINE | ID: mdl-35757987

RÉSUMÉ

Stomatal closure-associated actin-binding protein 1 (SCAB1) regulates stomatal closure by mediating actin filament reorganization in Arabidopsis thaliana. Our previous study showed that phosphatidylinositol 3-phosphate (PI3P) binds to SCAB1 and inhibits its oligomerization, thereby inhibiting its activity on F-actin in guard cells during stomatal closure. In this study, we show that another phospholipid, phosphatidic acid (PA), also binds to SCAB1 and inhibits its actin-bundling activity but not its actin-binding activity. F-actin bundling was promoted in vivo by treating Col-0 seedlings with n-butanol, a suppressor of PA production, but this effect was absent in the scab1 mutant. These results indicate that the signaling molecule PA is involved in the modulation of SCAB1 activity in F-actin reorganization.

14.
Eur J Med Chem ; 238: 114442, 2022 Aug 05.
Article de Anglais | MEDLINE | ID: mdl-35551036

RÉSUMÉ

Chronic myeloid leukemia (CML) is a malignant disease of the hematopoietic system with crucial pathogenic protein named BCR-ABL, which endangers the life of patients severely. As a milestone of targeted drug, Imatinib has achieved great success in the treatment of CML. Nevertheless, inevitable drug resistance of Imatinib has occurred frequently in clinical due to the several mutations in the BCR-ABL kinase. Subsequently, the second-generation of tyrosine kinase inhibitors (TKIs) against BCR-ABL was developed to address the mutants of Imatinib resistance, except T315I. To date, the third-generation of TKIs targeting T315I has been developed for improving the selectivity and safety. Notably, the first allosteric inhibitor has been in market which could overcome the mutations in ATP binding site effectively. Meanwhile, some advanced technology, such as proteolysis-targeting chimeras (PROTAC) based on different E3 ligand, are highly expected to overcome the drug resistance by selectively degrading the targeted proteins. In this review, we summarized the current research progress of inhibitors and degraders targeting BCR-ABL for the treatment of CML.


Sujet(s)
Antinéoplasiques , Leucémie myéloïde chronique BCR-ABL positive , Antinéoplasiques/pharmacologie , Antinéoplasiques/usage thérapeutique , Benzamides/usage thérapeutique , Résistance aux médicaments antinéoplasiques , Protéines de fusion bcr-abl , Humains , Mésilate d'imatinib/usage thérapeutique , Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Leucémie myéloïde chronique BCR-ABL positive/anatomopathologie , Pipérazines/pharmacologie , Inhibiteurs de protéines kinases/pharmacologie , Inhibiteurs de protéines kinases/usage thérapeutique , Pyrimidines/pharmacologie
15.
RSC Adv ; 12(16): 9763-9772, 2022 Mar 25.
Article de Anglais | MEDLINE | ID: mdl-35424925

RÉSUMÉ

A facile CuBr2 induced radical relay addition/cyclization of activated alkenes with substituted-thiosulfonates has been achieved, leading to a broad range of sulfonated indolo[2,1-a]isoquinolines and benzimidazo[2,1-a]isoquinolin-6(5H)-ones in moderate to good yields. In particular, some compounds exhibit bioactivity against cancer cell lines. This protocol shows advantages of low-cost, base-free, simple operation, and broad functional group tolerance.

16.
J Healthc Eng ; 2022: 8313415, 2022.
Article de Anglais | MEDLINE | ID: mdl-35432830

RÉSUMÉ

Neuropathic pain since early diabetes swamps patients' lives, and diabetes mellitus has become an increasingly worldwide epidemic. No agent, so far, can terminate the ongoing diabetes. Therefore, strategies that delay the process and the further complications are preferred, such as diabetic neuropathic pain (DNP). Dysfunction of ion channels is generally accepted as the central mechanism of diabetic associated neuropathy, of which hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) ion channel has been verified the involvement of neuropathic pain in dorsal root ganglion (DRG) neurons. Riluzole is a benzothiazole compound with neuroprotective properties on intervention to various ion channels, including hyperpolarization-activated voltage-dependent channels. To investigate the effect of riluzole within lumbar (L3-5) DRG neurons from DNP models, streptozocin (STZ, 70 mg/kg) injection was recruited subcutaneously followed by paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL), which both show significant reduction, whilst relieved by riluzole (4 mg/kg/d) administration, which was performed once daily for 7 consecutive days for 14 days. HCN2 expression was also decreased in line with alleviated behavioral tests. Our results indicate riluzole as the alleviator to STZ-induced DNP with involvement of downregulated HCN2 in lumbar DRG by continual systemic administration in rats.


Sujet(s)
Diabète , Neuropathies diabétiques , Névralgie , Animaux , Neuropathies diabétiques/complications , Neuropathies diabétiques/traitement médicamenteux , Neuropathies diabétiques/métabolisme , Ganglions sensitifs des nerfs spinaux/métabolisme , Canaux contrôlés par les nucléotides cycliques et activés par l'hyperpolarisation/métabolisme , Névralgie/complications , Névralgie/traitement médicamenteux , Névralgie/métabolisme , Neurones , Nucléotides cycliques/métabolisme , Nucléotides cycliques/pharmacologie , Canaux potassiques/métabolisme , Canaux potassiques/pharmacologie , Rats , Riluzole/métabolisme , Riluzole/pharmacologie , Riluzole/usage thérapeutique , Streptozocine/métabolisme , Streptozocine/pharmacologie
17.
Diagnostics (Basel) ; 11(8)2021 Aug 10.
Article de Anglais | MEDLINE | ID: mdl-34441379

RÉSUMÉ

Small intestinal bacterial overgrowth (SIBO) is characterized by abnormal and excessive amounts of bacteria in the small intestine. Since symptoms and lab tests are non-specific, the diagnosis of SIBO is highly dependent on breath testing. There is a lack of a universally accepted cut-off point for breath testing to diagnose SIBO, and the dilemma of defining "SIBO patients" has made it more difficult to explore the gold standard for SIBO diagnosis. How to validate the gold standard for breath testing without defining "SIBO patients" has become an imperious demand in clinic. Breath-testing datasets from 1071 patients were collected from Xiangya Hospital in the past 3 years and analyzed with an artificial intelligence method using cluster analysis. K-means and DBSCAN algorithms were applied to the dataset after the clustering tendency was confirmed with Hopkins Statistic. Satisfying the clustering effect was evaluated with a Silhouette score, and patterns of each group were described. Advantages of artificial intelligence application in adaptive breath-testing diagnosis criteria with SIBO were discussed from the aspects of high dimensional analysis, and data-driven and regional specific dietary influence. This research work implied a promising application of artificial intelligence for SIBO diagnosis, which would benefit clinical practice and scientific research.

18.
Zool Res ; 42(1): 130-134, 2021 Jan 18.
Article de Anglais | MEDLINE | ID: mdl-33377334

RÉSUMÉ

The Atlantic sea nettle ( Chrysaora quinquecirrha) has an important evolutionary position due to its high ecological value. However, due to limited sequencing technologies and complex jellyfish genomic sequences, the current C. quinquecirrha genome assembly is highly fragmented. Here, we used the most advanced high-throughput chromosome conformation capture (Hi-C) technology to obtain high-coverage sequencing data of the C. quinquecirrha genome. We then anchored these data to the previously published contig-level assembly to improve the genome. Finally, a high-continuity genome sequence of C. quinquecirrha was successfully assembled, which contained 1 882 scaffolds with a N50 length of 3.83 Mb. The N50 length of the genome assembly was 5.23 times longer than the previously released one, and additional analysis revealed that it had a high degree of genomic continuity and accuracy. Acquisition of the high-continuity genome sequence of C. quinquecirrha not only provides a basis for the study of jellyfish evolution through comparative genomics but also provides an important resource for studies on jellyfish growth and development.


Sujet(s)
Génome , Scyphozoa/génétique , Animaux , Évolution biologique , Analyse de séquence d'ADN/méthodes
19.
Environ Pollut ; 260: 114046, 2020 May.
Article de Anglais | MEDLINE | ID: mdl-32014747

RÉSUMÉ

Hexavalent chromium has aroused a series of environmental concerns due to its high mobility and toxicity. Iron and manganese oxides usually coexist in the environments and influence the speciation and geochemical cycling of chromium. However, the interaction mechanism of iron-manganese oxides with dissolved Cr(VI) remains largely unknown. In this work, the interaction processes of dissolved Cr(VI) and manganite in the presence of goethite coating were investigated, and the effects of pH (2.0-9.0) and iron oxide content were also studied. Manganite-goethite composites were formed with uniform micromorphologies in the system of manganite and Fe(II). In the reaction system of single manganite and Cr(VI), manganite could only adsorb but not reduce Cr(VI), with the adsorption amount decreasing at higher pHs. In the reaction system of manganite-goethite composites and Cr(VI), adsorbed Cr(VI) was reduced to Cr(III) by Fe(II) on composites surface. The generated Cr(III) was then retained as Cr(OH)3 on the mineral surface. Goethite coating suppressed the re-oxidation of newly formed Cr(III) by manganite. The amounts of adsorbed Cr(VI) and generated Cr(III) increased with increasing iron oxide content, and increased first and then decreased with increasing pH. The Cr(III) formation and Cr(VI) adsorption amount reached the maximum at pH 5.0-6.0. The present work highlights the transformation and retention of Cr(VI) by iron-manganese oxides and provides potential implications for the use of such oxides in the remediation of Cr(VI) polluted waters and soils.


Sujet(s)
Chrome/composition chimique , Composés du fer , Composés du manganèse , Minéraux , Oxydoréduction
20.
J Hazard Mater ; 390: 122166, 2020 05 15.
Article de Anglais | MEDLINE | ID: mdl-32004764

RÉSUMÉ

The speciation, toxicity and mobility of chromium (Cr) are significantly affected by natural iron-manganese nodules due to the adsorption and redox reactions in soils. However, the redox processes in oxic environments have received little attention. In this work, the interaction mechanism between Cr(III) and natural iron-manganese nodules was studied under oxic conditions, and the effects of chemical composition, dissolved oxygen concentration, pH, ionic strength and coexisting ions were further investigated. The results showed that iron-manganese nodules could effectively oxidize dissolved Cr(III), and most of the newly formed Cr(VI) was adsorbed on the surface of nodules. In iron-manganese nodules, manganese oxides mainly contributed to Cr(III) oxidation, and iron oxides facilitated the adsorption and immobilization of Cr(VI). In addition, Cr(III) could be catalytically oxidized to Cr(VI) on the surface of manganese oxides through the generation of Mn(III) intermediate or Mn(IV) oxides from released Mn(II) under oxic conditions. The oxidation rate of Cr(III) by the nodules decreased with increasing pH from 2.0 to 8.0, and increased with increasing ionic strength. This work reveals the adsorption and catalytic oxidation mechanism of Cr(III) by iron-manganese nodules in a simulated open system, and improves the understanding of the geochemical behavior of chromium in soils.

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