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1.
Ecotoxicol Environ Saf ; 187: 109765, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31670239

RESUMO

A novel polyvinyl alcohol/carboxymethyl cellulose/yeast double degradable hydrogel was prepared with yeast as a foaming agent. The chemical structure of the hydrogel was characterized by FTIR and XPS. The micro-structure of the hydrogel was observed by SEM. The specific surface area and pore size of hydrogel were measured by BET. Methylene blue adsorption capacity of the hydrogels were investigated and the adsorption mechanism was explored. The biodegradability of double degradable hydrogel was investigated. The results showed that yeast was encapsulated in hydrogel by electrostatic action. With the addition of yeast, not only the specific surface area and average pore size of the hydrogel increased but also methylene blue maximum adsorption capacity of the double degradable hydrogel (110 ±â€¯3.5 mg/g) was significantly higher than that of the hydrogel without yeast (57 ±â€¯1.9 mg/g). The adsorption mechanism was dominated by chemical adsorption and was accompanied by biodegradable and electrostatic adsorption. The kinetic data were fitted to the pseudo-second-order kinetic model reasonably well. The introduction of yeast promoted the biodegradable of hydrogel and increased the degradation rate of polyvinyl alcohol in the material with a maximum degradation rate of 45 ±â€¯2.8%.

2.
Food Chem ; 303: 125380, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445175

RESUMO

Soybean Bowman-Birk trypsin inhibitor (BBTI), an antinutritional factor of soy products, could strongly inhibit the protein digestion. The inactivation effect and mechanism of BBTI induced by tea polyphenols (TPs) and its major components (EGCG and EGC), were investigated in this study using fluorescence, FTIR, CD spectroscopy, isothermal titration calorimetry (ITC) and molecular docking. EGCG and EGC interacted with BBTI via static quenching process and hydrophobic interaction, with binding constant (Ka) of 2.19 × 103 M-1 and 0.25 × 103 M-1 at 298 K, respectively. TPs, EGCG and EGC induced a transition of BBTI conformation from disorder to order. ITC analysis and molecular docking revealed the interaction of EGCG-BBTI and EGC-BBTI were spontaneous, and hydrophobic interactions and hydrogen bonds were the predominant forces. Overall, this study clearly suggested that EGCG could be a promising inactivating agent for BBTI, which could also improve the safety and nutritional value of soy products.


Assuntos
Catequina/análogos & derivados , Simulação de Acoplamento Molecular , Inibidor da Tripsina de Soja de Bowman-Birk/química , Catequina/química , Catequina/farmacologia , Fluorescência , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Conformação Proteica , Termodinâmica , Inibidor da Tripsina de Soja de Bowman-Birk/efeitos dos fármacos , Inibidor da Tripsina de Soja de Bowman-Birk/metabolismo
3.
Chemosphere ; 238: 124695, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31545215

RESUMO

As the effective adsorbents, carbon materials (CMs) are typically used in the removal of disinfection byproduct (DBP) precursors during the water treatment by adding CMs before disinfection procedure. However, after the separation of CMs from the treated water by flocculation, sedimentation, and filtration, a small amount of loaded activated carbon could be released into the water treatment system and affect the DBP formation in the following disinfection. In this study, three CMs, including coal-made activated carbon (CAC), sawdust charcoal (SCC), and hydroxylated multiwall carbon nanotubes (OH-MWCNT), were used to explore the effects of residual CMs in the formation of DBPs. The results indicated that some DBP precursors could be irreversibly adsorbed into the pore structure of CMs and hardly to be extracted and determined, then affected the DBP formation in the water system. In the chlorination process of surface water samples, CMs have similar effects on the formation of DBPs. However, given that water samples contain a variety of complex substances, the effects of residual CMs on the formation of DBPs were also slightly changed.

4.
J Phys Condens Matter ; 32(3): 035808, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31590161

RESUMO

Single-crystalline FeTe2 in marcasite phase with orthorhombic structure was prepared via chemical vapor transport. Cooling FeTe2 single crystals from room temperature down to [Formula: see text], multiple magnetic phase transitions were observed. Paramagnetic (PM) to antiferromagnetic (AFM) and then to ferromagnetic (FM) occurred at [Formula: see text] and [Formula: see text] for in-plane, [Formula: see text] and [Formula: see text] for out-of-plane, respectively. A strong uniaxial magnetic anisotropy was found due to FeTe6 octahedron distortion and structural modulation in FM region. The novel negative volume expansion (NVE) initiated in the vicinity of AFM to FM transition. An abrupt frequency shift of the most intense mode at [Formula: see text] and evolution of the Te-Te stretching mode near [Formula: see text], corresponding to the phase transition from AFM to FM were observed. The temperature-dependent resistance revealed an anomaly (semiconductor to metallic transition) around AFM-FM transition, which can easily be suppressed and move to high temperature by the applied magnetic field. The results from XRD, Raman and resistivity indicated that the structural parameters, vibration frequency and transport are sensitive to the phase transition from AFM to FM. The nature of direct band gap with [Formula: see text] was identified through UV-Vis-NIR spectrum of FeTe2 single crystals at room temperature.

5.
Sci Total Environ ; : 135224, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31796275

RESUMO

Microbial remediation is a promising technique to remediate heavy metals contaminated soils. In this study, the cadmium (Cd)- resistant Citrobacter sp. XT1-2-2, isolated from heavy metals contaminated paddy soils, was investigated to evaluate the effect of this strain on soil Cd speciation, cellular Cd distribution, tissue Cd accumulation and rice biomass. The percentage of Cd2+ removal by Citrobacter sp. XT1-2-2 was up to 82.3 ± 2.1% within 240 min in the solution. The average content of soil soluble plus exchangeable and carbonate-bound fractions of Cd decreased, whereas Fe/Mn oxide-bound, organic matter-bound and residual fractions increased with bacteria inoculation. For the paddy soil inoculated with the XT1-2-2 strain, Cd concentrations of roots, culms, leaves and grains were significantly reduced by 24.1%, 46.9%, 41.5% and 66.7%, respectively. In addition, inoculation bacteria significantly increased the biomass of the roots, above-ground tissues and the rice grains. All results indicated that the XT1-2-2 strain had the ability to immobilize soil Cd and decrease Cd accumulation in rice grains. Therefore, the XT1-2-2 strain has potential for application to remediate Cd-contaminated paddy soils. It is possible to exploit a new bacterial-assisted technique for the remediation in Cd-contaminated paddy soils.

6.
Dent Mater ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31785833

RESUMO

OBJECTIVE: Disruption of the demineralization-remineralization balance could trigger the development of dental caries, making it challenging for enamel to "self-heal". Thus, extrinsic assistance is needed to restore enamel lesions and stop undermining progression. The aim of this study was to investigate enamel remineralization in a simulated oral environment via poly (amino amine) (PAMAM) dendrimers quantitatively. METHODS: Bovine enamel specimens were shaken in demineralization solution (pH 4.5, 37°C, 50rpm/min) for 72h to create initial enamel carious lesions. The subsurface-demineralized specimens were then divided into four groups: enamel treated with PAMAM-NH2, enamel treated with PAMAM-COOH, enamel treated with PAMAM-OH, and enamel treated with deionized water. The treated specimens underwent subsequent 12-day pH cycling. Enamel blocks were analyzed by transverse microradiography (TMR), surface microhardness testing and scanning electron microscopy (SEM) before and after demineralization and pH cycling. RESULTS: Groups treated with PAMAM dendrimers showed lower lesion depth and less mineral loss, attained more vertical-section surface microhardness recovery, and adsorbed more mineral deposits (p<0.05). The enamel lesion remineralization values of PAMAM-NH2, PAMAM-COOH, and PAMAM-OH groups were 76.42±3.32%, 60.07±5.92% and 54.52±7.81%, respectively. SIGNIFICANCE: In conclusion, PAMAM with different terminal groups could induce enamel remineralization, among which PAMAM-NH2 showed the most prominent competence, followed by PAMAM-COOH and PAMAM-OH, in that order.

7.
Chemistry ; 25(67): 15217, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31793089

RESUMO

Invited for the cover of this issue is the group of Min Zhang and Weiping Su at the Fujian Institute of Research on the Structure of Matter. Read the full text of the article at 10.1002/chem.201903551.

8.
Am J Trop Med Hyg ; 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31802727

RESUMO

Wound dressings are always needed after skin injury; however, most of the dressings still leave room for improvement. Here, we would like to develop an effective dressing with the ability to improve wound healing. A chitosan-Vaseline gauze (CVG) dressing was developed by coating the chitosan mixture and Vaseline on sterile gauze with subsequent drying. Infrared spectroscopy and electron microscopy were used to investigate the miscibility and structure of the dressing. The cytotoxicity and antibacterial nature were evaluated in vitro. The studies of water retention rate, wound healing, and tissue compatibility were carried out over a period of 14 days on full-thickness skin wounds of male Sprague-Dawley rats. It was observed that the CVG dressing demonstrated functional structure by miscibility, non-cytotoxicity, and good antibacterial effects against both Gram-positive and Gram-negative bacteria. The water retention rate incresased up to 25% after applying CVG for 3 hours. Besides, CVG treatment increased angiogenesis and improved microvascular density in wounds. The wounds treated with CVG showed size deduction with new collagen aggregations similar to those in the normal dermis. All the aforementioned results suggest that CVG dressing could be a promising candidate for wound treatment.

9.
J Neuroimmunol ; 339: 577114, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31775073

RESUMO

Anti-dipeptidyl-peptidase-like protein 6 (DPPX) encephalitis is a rare type of autoimmune encephalitis. We present a case of a 72-year-old male with anti-DPPX encephalitis who developed rapidly progressive cognitive decline, psychiatric and sleep problems, severe abdominal pain and diarrhea. Antibodies against DPPX were positive both in serum and cerebrospinal fluid. 18F-FDG PET-MR imaging indicated hypometabolism in the bilateral temporal lobes and thalamus. No related tumors were found, and the patient responded to immunotherapy without relapse at the 3-year follow-up. The present case enriches the understanding of the clinical, imaging manifestations and prognosis of anti-DPPX encephalitis.

10.
Plant Physiol Biochem ; 146: 269-277, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31783202

RESUMO

3-Hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR) is the first rate-limiting enzyme regulating the synthesis of terpenoids upstream of the mevalonate (MVA) pathway. In higher plants, members of the HMGR genes families play an important role in plant growth and development and in response to various environmental stresses. In the present study, a novel HMGR gene, designated MdHMGR5, was isolated from apple (Malus domestica L.) and characterized. Expression of MdHMGR5 enhanced the activity of HMGR enzyme in transgenic Arabidopsis thaliana L. plants. Under oxidative stress, transgenic A. thaliana plants over-expressing MdHMGR5 had a higher germination rate, a longer main root length, higher chlorophyll and proline content, and higher activities of antioxidant enzymes. On the other hand, malondialdehyde (MDA) content, relative conductivity and reactive oxygen species (ROS) production rate were significantly lower than in wild type plants. These results indicated that over-expression of MdHMGR5 enhanced plant tolerance to oxidative stress by scavenging ROS in transgenic plants. Over-expression of MdHMGR5 also affected the expression levels of genes in mevalonic acid and 2C-methyl-D-erythritol 4-phosphate (MVA and MEP) pathways of A. thaliana plants. These results indicate that over-expression of MdHMGR5 enhances tolerance to oxidative stress by maintaining photosynthesis and scavenging ROS in transgenic A. thaliana plants.

11.
Stem Cells ; 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31721359

RESUMO

Histone deacetylase 7 (HDAC7) plays a pivotal role in the maintenance of the endothelium integrity. In this study, we demonstrated that the intron-containing Hdac7 mRNA existed in the cytosol and that ribosomes bound to a short open reading frame (sORF) within the 5' terminal non-coding area of this Hdac7 mRNA in response to vascular endothelial growth factor (VEGF) stimulation in the isolated stem cell antigen-1 positive (Sca1+ ) vascular progenitor cells (VPCs). A 7-amino acid (7A) peptide has been demonstrated to be translated from the sORF in Sca1+ -VPCs in vitro and in vivo. The 7A peptide was shown to receive phosphate group from the activated mitogen-activated protein kinase MEKK1 and transfer it to 14-3-3 gamma protein, forming an MEKK1-7A-14-3-3γ signal pathway downstream VEGF. The exogenous synthetic 7A peptide could increase Sca1+ -VPCs cell migration, reendothelialization in the femoral artery injury and angiogenesis in hindlimb ischemia. An Hd7-7sFLAG transgenic mice line was generated as the loss-of-function model, in which the 7A peptide was replaced by a FLAG-tagged scrabbled peptide. Loss of the endogenous 7A impaired Sca1+ -VPCs cell migration, reendothelialization of the injured femoral artery and angiogenesis in ischemic tissues, which could be partially rescued by the addition of the exogenous 7A/7Ap peptide. This study provides evidence that sORFs can be alternatively translated and the derived peptides may play an important role in physiological processes including vascular remodeling. © AlphaMed Press 2019 SIGNIFICANCE STATEMENT: Histone deacetylase 7 (HDAC7) plays a pivotal role in the maintenance of the endothelial integrity. Short open reading frames (sORFs) exist within the 5' terminal non-coding area of Hdac7 mRNA. It remains unclear whether these sORFs contribute to HADC7 functions. In this study, we demonstrated that a 7-amino acid peptide could be translated from a sORF. This peptide could act as phosphate group carrier, forming a novel signal transduction pathway, the MEKK1-7A-14-3-3? pathway, downstream VEGF. The novel signal pathway may be involved in vessel wall resident stem/progenitor cell activation and vascular remodeling.

12.
PLoS Genet ; 15(10): e1008460, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31671093

RESUMO

Malfunction of pre-mRNA processing factors are linked to several human diseases including cancer and neurodegeneration. Here we report the identification of a de novo heterozygous missense mutation in the SNRPE gene (c.65T>C (p.Phe22Ser)) in a patient with non-syndromal primary (congenital) microcephaly and intellectual disability. SNRPE encodes SmE, a basal component of pre-mRNA processing U snRNPs. We show that the microcephaly-linked SmE variant is unable to interact with the SMN complex and as a consequence fails to assemble into U snRNPs. This results in widespread mRNA splicing alterations in fibroblast cells derived from this patient. Similar alterations were observed in HEK293 cells upon SmE depletion that could be rescued by the expression of wild type but not mutant SmE. Importantly, the depletion of SmE in zebrafish causes aberrant mRNA splicing alterations and reduced brain size, reminiscent of the patient microcephaly phenotype. We identify the EMX2 mRNA, which encodes a protein required for proper brain development, as a major mis-spliced down stream target. Together, our study links defects in the SNRPE gene to microcephaly and suggests that alterations of cellular splicing of specific mRNAs such as EMX2 results in the neurological phenotype of the disease.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31669564

RESUMO

PURPOSE: To compare toxicity and biochemical control in post-prostatectomy patients treated with conventional (66 Gy) or dose-intensified (72 Gy) radiotherapy. METHODS: Patients who had stage pT3-4, positive surgical margins, or rising PSA ≥ 0.2 ng/mL following radical prostatectomy were randomly assigned to receive either 66 Gy in 33 fractions or 72 Gy in 36 fractions. A primary endpoint was to assess the difference in biochemical progression-free survival (bPFS) between these two cohorts, and secondary endpoints were to assess differences in genitourinary (GU), gastrointestinal (GI), and hematologic (HT) toxicities between these two cohorts. bPFS was estimated by the Kaplan-Meier method and toxicities were compared using the χ2 test. RESULTS: Between September 2011 and November 2016, 144 patients were enrolled: 71 patients to the 66 Gy cohort and 73 patients to the 72 Gy cohort. The median follow-up time was 48.5 months (range: 14-79 months). There was no difference in 4-year bPFS between the 66 Gy and 72 Gy cohorts (75.9% vs. 82.6%; P = 0.299). However, in patients with a higher Gleason score (GS; 8-10), the 72 Gy cohort had statistically significant improvement in bPFS compared with the 66 Gy cohort (79.7% vs. 55.7%; P = 0.049). Toxicity analysis showed no difference in ≥2 acute or late GI or GU toxicities between these two cohorts. A total of 48 patients were scored as urinary incontinence before RT, of which 39 (81.3%) reported incontinence recovery or stable at 1-year follow-up, while only 9 (18.8%) patients reported worsening. There was no difference between the two cohorts in urinary incontinence either at baseline or at 1-year follow-up. CONCLUSION: Dose escalation (72 Gy) demonstrated no improvement in 4-year bPFS compared with the 66 Gy regimen. However, the dose escalation was not associated with greater acute or late GU or GI toxicities, and did not increase urinary incontinence.

14.
J Agric Food Chem ; 67(48): 13247-13257, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31707781

RESUMO

Dietary interventions alter the formation of the disease-associated metabolite, trimethylamine (TMA), via intestinal microbial TMA lyase activity. Nevertheless, the mechanisms regulating microbial enzyme production are still unclear. Sequencing of the gut bacteria 16S rDNA demonstrated that dietary intervention changed the composition of the gut microbiota and the functional metagenome involved in the choline utilization pathway. Characterization of the functional profile of the metagenomes and metabonomics analysis revealed that a series of Kyoto Encyclopedia of Genes and Genomes orthologous groups and enzyme groups related to accumulation of methylglyoxal (MG) and glycine were enriched in red meat diet-fed animals, whereas fiber-rich diet suppressed glycine formation via the MG-dependent pathway. Our observations suggest associations between choline-TMA lyase expression and MG formation, which are indicative of a novel role of the gut microbiota in choline metabolism and highlight it as a potential target for inhibiting TMA production.

15.
Biometrics ; 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31733066

RESUMO

Causal mediation analysis aims to examine the role of a mediator or a group of mediators that lie in the pathway between an exposure and an outcome. Recent biomedical studies often involve a large number of potential mediators based on high-throughput technologies. Most of the current analytic methods focus on settings with one or a moderate number of potential mediators. With the expanding growth of -omics data, joint analysis of molecular-level genomics data with epidemiological data through mediation analysis is becoming more common. However, such joint analysis requires methods that can simultaneously accommodate high-dimensional mediators and that are currently lacking. To address this problem, we develop a Bayesian inference method using continuous shrinkage priors to extend previous causal mediation analysis techniques to a high-dimensional setting. Simulations demonstrate that our method improves the power of global mediation analysis compared to simpler alternatives and has decent performance to identify true non-null contributions to the mediation effects of the pathway. The Bayesian method also helps us to understand the structure of the composite null cases for inactive mediators in the pathway. We applied our method to Multi-Ethnic Study of Atherosclerosis (MESA) and identified DNA methylation regions that may actively mediate the effect of socioeconomic status (SES) on cardiometabolic outcomes. This article is protected by copyright. All rights reserved.

16.
Mol Immunol ; 117: 73-83, 2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31743855

RESUMO

Autoimmune myocarditis is a cause of dilated cardiomyopathy and heart failure. MicroRNAs regulate many immune processes, but their role in aberrant inflammation during autoimmune myocarditis remains unclear. In this study, we investigated the role of miR-223-3p in experimental autoimmune myocarditis (EAM). We found that miR-223-3p expression was significantly lower in EAM mice than that in normal mice. miR-223-3p inhibited NLRP3 inflammasome expression, promoting the polarization of dendritic cells (DCs) towards a tolerogenic DC phenotype. miR-223-3p effectively induced regulatory T cell (Treg) generation by inhibiting the function of antigen-presenting DCs. Transfer of miR-223-3p-overexpressing DCs protected mice against the development of EAM. Our findings suggest that miR-223-3p is involved in the induction of the tolerogenic DC phenotype and regulates tolerance in autoimmune myocarditis.

17.
Food Funct ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746888

RESUMO

It has been revealed in our previous studies that trypsin scavenges superoxide anions. In the current study, the mechanisms of storage quality improvement by trypsin were evaluated in H. undatus. Strikingly, the improvement is due not to its antibacterial or antifungal activity but to its superoxide scavenging activity. Moreover, trypsin significantly decreased the levels of ROS, cell permeability and membrane lipid peroxidation. The activities of major antioxidant enzymes were significantly improved by trypsin treatment. Transcriptome profiles of H. undatus treated with trypsin revealed the pathways and regulatory mechanisms of antioxidant genes up or down-regulated following trypsin treatment by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses. The results of protein-protein interaction networks indicated that CAT is the key among the enzymes of the complicated antioxidant system. In addition, the current results showed that the synergistic effect of trypsin with antioxidant enzymes can regulate the levels of endogenous active oxygen species, reduce malondialdehyde content, improve cell membrane integrity, alleviate cell damage and delay fruit ageing.

18.
Int J Biol Macromol ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31758996

RESUMO

Aimed to evaluate the hypolipidemic effects of high molecular weight soluble dietary fiber extracted from L. edodes (LEHSDF), this study investigated the structure and interaction mechanism of LEHSDF with pancreatic lipase (PL) and bile salts (BS) that were involved in lipid digestion. 1D/2D NMR spectra indicated that the main chain of LEHSDF consisted of (1→2,4)-linked ß-D-arabinopyranosyl, (1→3)-linked α-L-rhamnopyranosyl, (1→4)-linked ß-D-xylopyranosyl, (1→6)-linked and (1→4)-linked ß-D-glucopyranosyl, with ß-D-galactopyranosyl and α-D-mannopyranosyl as terminal unit. Oil red O staining results suggested that LEHSDF had an effective inhibitory effect on lipid accumulation in HepG2 cells. Isothermal titration calorimetry, fluorescence and circular dichroism spectra showed that BS did not specifically bind to LEHSDF, and the strong inhibitory effect of LEHSDF on lipase was dominated by hydrophobic forces, electrostatic forces, encapsulation and adsorption interactions. The results will be helpful for the design of food containing LEHSDF as a functional additive to control lipid digestion.

19.
Chin Med J (Engl) ; 132(22): 2737-2744, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31725458

RESUMO

OBJECTIVE: To review the diagnosis of chronic wound biofilms and discuss current treatment approaches. DATA SOURCES: Articles included in this review were obtained from the following databases: Wanfang, China National Knowledge Infrastructure, PubMed, and the Web of Science. We focused on research published before August 2019 with keywords including chronic wound, biofilm, bacterial biofilms, and chronic wound infection. STUDY SELECTION: Relevant articles were selected by carefully reading the titles and abstracts. Further, different diagnosis and clinical treatment methods for chronic wound biofilm were compared and summarized from the selected published articles. RESULTS: Recent guidelines on medical biofilms stated that approaches such as the use of scanning electron microscopy and confocal laser scanning microscopy are the most reliable types of diagnostic techniques. Further, therapeutic strategies include debridement, negative pressure wound therapy, ultrasound, antibiotic, silver-containing dressing, hyperbaric oxygen therapy, and others. CONCLUSION: This review provides the identification and management of biofilms, and it can be used as a tool by clinicians for a better understanding of biofilms and translating research to develop best clinical practices.

20.
Sci Total Environ ; 702: 134803, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31731125

RESUMO

Photosynthetic picoeukaryotes (PPEs) are key players in aquatic systems, while their diversity and community composition dynamics remain poorly understood. The monthly composition of PPEs in Lake Chaohu was investigated using a combination of flow cytometry sorting and high throughput sequencing. Results indicated that temperature is the most important factor shaping PPEs community structure. The PPEs community can be categorized into three groups that are dominant at different temperature ranges: high temperature (>21.8 °C), intermediate temperature (between 9.8 °C and 21.8 °C) and low temperature (<9.8 °C). At the supergroup level, Cryptophyta were dominant at the intermediate temperature level, and Bacillariophyta were prevalent at low temperatures. In comparison, Chlorophyta PPEs were sensitive to temperature at the order level. Molecular network analysis using 18S rDNA sequencing results from sorted samples revealed that the Operational Taxonomic Units (OTUs) of PPE from the same taxonomic groups were predominantly positive, implying that they were occupying similar niches. The cooccurrence patterns between PPEs and fungi were mostly negative. In particular, OTU101, which was associated with Chytridiomycota, was negatively related to many OTUs belonging to Chlorophyta and Diatom, indicating that their potential parasitic associations may be not species-specific.

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