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1.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-38112223

RESUMO

To investigate whether intermittent theta burst stimulation over the cerebellum induces changes in resting-state electroencephalography microstates in patients with subacute stroke and its correlation with cognitive and emotional function. Twenty-four stroke patients and 17 healthy controls were included in this study. Patients and healthy controls were assessed at baseline, including resting-state electroencephalography and neuropsychological scales. Fifteen patients received lateral cerebellar intermittent theta burst stimulation as well as routine rehabilitation training (intermittent theta burst stimulation-RRT group), whereas 9 patients received only conventional rehabilitation training (routine rehabilitation training group). After 2 wk, baseline data were recorded again in both groups. Stroke patients exhibited reduced parameters in microstate D and increased parameters in microstate C compared with healthy controls. However, after the administration of intermittent theta burst stimulation over the lateral cerebellum, significant alterations were observed in the majority of metrics for both microstates D and C. Lateral cerebellar intermittent theta burst stimulation combined with conventional rehabilitation has a stronger tendency to improve emotional and cognitive function in patients with subacute stroke than conventional rehabilitation. The improvement of mood and cognitive function was significantly associated with microstates C and D. We identified electroencephalography microstate spatiotemporal dynamics associated with clinical improvement following a course of intermittent theta burst stimulation therapy.


Assuntos
Eletroencefalografia , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/complicações , Estimulação Magnética Transcraniana , Cerebelo , Cognição
2.
Int Microbiol ; 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38506947

RESUMO

A novel enrofloxacin-degrading fungus was isolated from a rhizosphere sediment of the submerged macrophyte Vallisneria spiralis L.. The isolate, designated KC0924g, was identified as a member of the genus Humicola based on morphological characteristics and tandem conserved sequence analysis. The optimal temperature and pH for enrofloxacin degradation by strain KC0924g were 28 °C and 9.0, respectively. Under such condition, 98.2% of enrofloxacin with an initial concentration of 1 mg L-1 was degraded after 72 h of incubation, with nine possible degradation products identified. Four different metabolic pathways were proposed, which were initiated by cleavage of the piperazine moiety, hydroxylation of the aromatic ring, oxidative decarboxylation, or defluorination. In addition to enrofloxacin, strain KC0924g also degraded other fluoroquinolone antibiotics (ciprofloxacin, norfloxacin, and ofloxacin), malachite green (an illegal additive in aquaculture), and leucomalachite green. Pretreatment of cells of strain KC0924g with Cu2+ accelerated ENR degradation. Furthermore, it was speculated that a flavin-dependent monooxygenase was involved in ENR degradation, based on the increased transcriptional levels of these two genes after Cu2+ induction. This work enriches strain resources for enrofloxacin remediation and, more importantly, would facilitate studies on the molecular mechanism of ENR degradation with degradation-related transcriptome available.

3.
Horm Metab Res ; 55(6): 420-425, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36599457

RESUMO

Pancreatic cancer (PC) has the lowest survival rate and the highest mortality rate among all cancers due to lack of effective treatments. The objective of the current study was to identify potential therapeutic targets in PC. Three transcriptome datasets, namely GSE62452, GSE46234, and GSE101448, were analyzed for differentially expressed genes (DEGs) between cancer and normal samples. Several bioinformatics methods, including functional analysis, pathway enrichment, hub genes, and drugs were used to screen therapeutic targets for PC. Fisher's exact test was used to analyze functional enrichments. To screen DEGs, the paired t-test was employed. The statistical significance was considered at p <0.05. Overall, 60 DEGs were detected. Functional enrichment analysis revealed enrichment of the DEGs in "multicellular organismal process", "metabolic process", "cell communication", and "enzyme regulator activity". Pathway analysis demonstrated that the DEGs were primarily related to "Glycolipid metabolism", "ECM-receptor interaction", and "pathways in cancer". Five hub genes were examined using the protein-protein interaction (PPI) network. Among these hub genes, 10 known drugs targeted to the CPA1 gene and CLPS gene were found. Overall, CPA1 and CLPS genes, as well as candidate drugs, may be useful for PC in the future.


Assuntos
Perfilação da Expressão Gênica , Neoplasias Pancreáticas , Humanos , Perfilação da Expressão Gênica/métodos , Biomarcadores Tumorais/genética , Detecção Precoce de Câncer/métodos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/diagnóstico , Biologia Computacional/métodos , Neoplasias Pancreáticas
4.
Altern Ther Health Med ; 29(8): 452-460, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652416

RESUMO

Context: Ras-associated binding 35 (RAB35) is an oncogenic, guanosine triphosphate (GTP)ase that plays a role in cancer invasion, metastasis, and immune evasion. However, systematic and comprehensive research to identify the importance of RAB35 in various cancer types is still absent. Objective: The study intended to explore the potential value of RAB35 as a molecular biomarker. Design: The research team performed a genetic evaluation of RAB35. Setting: The study took place at the Second Affiliated Hospital of Wenzhou Medical University in Wenzhou, China. Outcome Measures: The research team assessed the expression of RAB35 in various tumor tissues and performed correlation analyses between RAB35 expression and prognosis, molecular subtypes, immunological subtypes, immune-associated cell infiltration, the tumor immune microenvironment, and drug sensitivity in pan-cancer. Results: RAB35 exhibited significant differential expression for 21 cancer types. It demonstrated high sensitivity and specificity in diagnosing eight cancer types, showed distinct expression patterns in various molecular subtypes for six cancer types, and found different immune subtypes for eight cancer types. The abnormal expression of RAB35 was significantly related to overall survival (OS) for nine cancer types, progress free interval (PFI) for five cancer types, and disease-specific survival (DSS) for five cancer types. Its abnormal expression was closely associated with the immune microenvironment and multiple immune cells. Furthermore, it was related to the drug sensitivity for various drugs and might be associated with chemotherapy resistance. Conclusions: RAB35 showed significant differential expression in various cancers and was significantly related to the prognosis of cancer patients, the immune microenvironment, multiple immune cells, drug sensitivity to various drugs, and chemotherapy resistance. It may serve as a potential biomarker and therapeutic target for cancer treatment.


Assuntos
Neoplasias , Humanos , Prognóstico , Neoplasias/diagnóstico , China , Biomarcadores , Microambiente Tumoral , Proteínas rab de Ligação ao GTP/genética
5.
J Environ Manage ; 345: 118897, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37683386

RESUMO

Nitrate and SMX both play a critical role in their biotransformation in biodegradable polymer-supported denitrification biofilters. However, the mutual influences of nitrate and SMX on their biotransformation for long-term operation remained obscure. Results showed SMX and nitrate had divergent effects on SMX removal. SMX removal rates was positively related with its loading rates, whereas they were negatively related to NLRs. The most abundant metabolite C10H14O3N3S (the reduced form of SMX moiety) from the N-O bond cleavage pathway by UHPLC-LTQ-Orbitrap-MS/MS and effluent TOC variations confirmed the presence of electron donor competition between nitrate and SMX. SMX less than 1000 µg/L had a negligible influence on denitrification performance. Denitrifiers such as Azospira and Denitratisoma were still enriched after chronic exposure, and nosZ/narG positively correlated with sul1/sul2 resistance genes, which were both responsible for the negligible influence of SMX. This work could guide the operational management of denitrification biofilters for simultaneous nitrate and antibiotics removal.


Assuntos
Nitratos , Sulfametoxazol , Ácido 3-Hidroxibutírico , Desnitrificação , Espectrometria de Massas em Tandem , Biotransformação , Hidroxibutiratos
6.
J Cell Mol Med ; 26(18): 4859-4871, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35989423

RESUMO

RNA-binding Motif Protein39 (RBM39) is identified as a splicing factor and transcription coactivator. Despite mounting evidence that RBM39 plays a critical role in the development of specific malignancies, no systematic pan-cancer investigation of RBM39 has been conducted. As a result, we set out to investigate RBM39's prognostic significance and putative immunological activities in 33 different cancers. Based on TCGA and CCLE, GTEx, cBioportal and HPA, we used a series of bioinformatics approaches to explore the potential oncogenic role of RBM39, including analysis of the expression of the pan-cancer species RBM39, the prognostic relationship between RBM39 expression and overall survival (OS), disease-specific survival (DSS) and progression-free interval (PFI), the relationship between RBM39 expression and clinical phenotype, analysis of the relationship between RBM39 expression and tumour mutational burden (TMB), microsatellite instability (MSI), DNA methylation and immune cell infiltration. Our results showed that RBM39 is overexpressed in most cancers. RBM39 was positively or negatively correlated with the prognosis of different tumours. RBM39 expression was associated with TMB and MSI in 9 and 12 cancer types. In addition, RBM39 expression was associated with DNA methylation in almost all tumours. There are eight tumours were screened for further study, including BRCA, COAD, HNSC, LIHC, LUSC, SKCM, STAD, UCEC. In the screed tumours, RBM39 was found to be negatively correlated with the infiltration of most immune cells. In addition, the correlation with RBM39 expression varied by immune cell subtype. Based on RBM39's role in tumorigenesis and tumour immunity, we suggest it can serve as a surrogate prognostic marker.


Assuntos
Neoplasias , Proteínas de Ligação a RNA , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Humanos , Instabilidade de Microssatélites , Neoplasias/patologia , Prognóstico , Motivos de Ligação ao RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
7.
Int J Clin Pract ; 2022: 5734387, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36177365

RESUMO

Background: The purpose of this study was to determine whether oxybuprocaine hydrochloride gel could alleviate pain during male catheterization. Methods: Between September 2021 and March 2022, a randomized controlled trial was conducted at the Urology Department of Harbin Medical University Cancer Hospital (China). A total of 192 adult male patients requiring catheterization were enrolled and randomly assigned to one of two groups: 96 in the test group and 96 in the control group. The test group included patients who received oxybuprocaine hydrochloride gel as urethral lubricant, while patients in the control group received liquid paraffin. The preoperative and postoperative pain scores were compared using nonparametric tests. Results: At the baseline, there was no significant difference between the two groups. There was no significant difference in preoperative pain scores between the test group (mean ± SD = 20.04 ± 2.68 mm) and the control group (mean ± SD = 20.21 ± 3.23 mm) (p=0.694). Postoperative pain scores increased significantly in the test (mean ± SD = 31.98 ± 2.57 mm, p < 0.001) and control groups (mean ± SD = 38.96 ± 2.02 mm, p < 0.001) groups. Postoperative pain scores were significantly lower in the test group (mean ± SD = 31.98 ± 2.57 mm) than those in the control group (mean ± SD = 38.96 ± 2.02 mm (p < 0.001). Conclusions: The use of oxybuprocaine hydrochloride gel significantly reduced pain during male urethral catheterization. The study provides evidence for clinicians to use oxybuprocaine hydrochloride gel during male catheterization.


Assuntos
Anestésicos Locais , Cateterismo Urinário , Adulto , Anestésicos Locais/efeitos adversos , Humanos , Lubrificantes , Masculino , Óleo Mineral , Medição da Dor , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Procaína/análogos & derivados , Cateterismo Urinário/efeitos adversos
8.
Pestic Biochem Physiol ; 148: 190-198, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29891372

RESUMO

Pyrethroid insecticides modify the gating of voltage-gated sodium channels, thus disrupting the function of the nervous system. In Drosophila melanogaster, para encodes a functional sodium channel. Drosophila Sodium Channel 1 (DSC1), although considered as a putative sodium channel gene for decades due to its high sequence similarity with sodium channels, encodes a voltage-gated cation channel with high permeability to Ca2+. Previous study showed that knockout of the DSC1 gene (DSC1-/-) caused Drosophila adults to be more susceptible to pyrethroids and the adult giant fiber (GF) neural circuit were more susceptible to pyrethroids. Considering distinct expression of DSC1 transcripts in adults and larvae, we examined the role of DSC1 channels in regulating pyrethroid susceptibility in Drosophila larvae. We conducted insecticide bioassays and examined the susceptibility of the larval neuromuscular junction (NMJ) to pyrethroids using w1118, an insecticide-susceptible line, DSC1-/-, parats1 (a pyrethroid-resistant line carrying a mutation in para) and a double mutation line parats1; DSC1-/-. We found that, like the adult GF system, the NMJ of DSC1-/- flies is more susceptible to pyrethroids than that of w1118 with the pyrethroid susceptibility ranked as DSC1-/- > w1118 > parats1; DSC1-/- > parats1. However, DSC1-/- larvae were about two-fold more resistant to pyrethroids than w1118 larvae, and the pyrethroid susceptibility of larvae ranked as w1118 > DSC1-/- > parats1; DSC1-/- > parats1. These results reveal common and distinct roles of DSC1 channels in regulating the action of pyrethroids in adults and larvae of D. melanogaster.


Assuntos
Canais de Cálcio/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/efeitos dos fármacos , Resistência a Inseticidas/genética , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Piretrinas/toxicidade , Animais , Bioensaio , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Mutação , Junção Neuromuscular/efeitos dos fármacos , Ligação Proteica , Canais de Sódio Disparados por Voltagem/metabolismo
9.
Appl Environ Microbiol ; 83(18)2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28710269

RESUMO

Buprofezin is a widely used insect growth regulator whose residue has been frequently detected in the environment, posing a threat to aquatic organisms and nontarget insects. Microorganisms play an important role in the degradation of buprofezin in the natural environment. However, the relevant catabolic pathway has not been fully characterized, and the molecular mechanism of catabolism is still completely unknown. Rhodococcus qingshengii YL-1 can utilize buprofezin as a sole source of carbon and energy for growth. In this study, the upstream catabolic pathway in strain YL-1 was identified using tandem mass spectrometry. Buprofezin is composed of a benzene ring and a heterocyclic ring. The degradation is initiated by the dihydroxylation of the benzene ring and continues via dehydrogenation, aromatic ring cleavage, breaking of an amide bond, and the release of the heterocyclic ring 2-tert-butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one (2-BI). A buprofezin degradation-deficient mutant strain YL-0 was isolated. A comparative genomic analysis combined with gene deletion and complementation experiments revealed that the gene cluster bfzBA3A4A1A2C is responsible for the upstream catabolic pathway of buprofezin. The bfzA3A4A1A2 cluster encodes a novel Rieske nonheme iron oxygenase (RHO) system that is responsible for the dihydroxylation of buprofezin at the benzene ring; bfzB is involved in dehydrogenation, and bfzC is in charge of benzene ring cleavage. Furthermore, the products of bfzBA3A4A1A2C can also catalyze dihydroxylation, dehydrogenation, and aromatic ring cleavage of biphenyl, flavanone, flavone, and bifenthrin. In addition, a transcriptional study revealed that bfzBA3A4A1A2C is organized in one transcriptional unit that is constitutively expressed in strain YL-1.IMPORTANCE There is an increasing concern about the residue and environmental fate of buprofezin. Microbial metabolism is an important mechanism responsible for the buprofezin degradation in the natural environment. However, the molecular mechanism and genetic determinants of microbial degradation of buprofezin have not been well identified. This work revealed that gene cluster bfzBA3A4A1A2C is responsible for the upstream catabolic pathway of buprofezin in Rhodococcus qingshengii YL-1. The products of bfzBA3A4A1A2C could also degrade bifenthrin, a widely used pyrethroid insecticide. These findings enhance our understanding of the microbial degradation mechanism of buprofezin and benefit the application of strain YL-1 and bfzBA3A4A1A2C in the bioremediation of buprofezin contamination.

10.
Biotechnol Lett ; 38(12): 2109-2117, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27578391

RESUMO

OBJECTIVES: To induce natural genetic competence in Bacillus amyloliquefaciens isolates through overexpression of the master regulator, ComK, from B. subtilis (ComK Bsu ). RESULTS: Plasmid pUBXC carrying the xylose-inducible comK expression cassette was constructed using plasmid pUB110 as a backbone. Plasmid pUBXC could be transferred from B. subtilis to B. amyloliquefaciens through plasmid pLS20-mediated biparental conjugation. After being induced by xylose, four B. amyloliquefaciens strains harbouring plasmid pUBXC developed genetic competence. Under optimal conditions, the transformation efficiencies of plasmid DNA ranged from 129 ± 20.6 to 1.7 ± 0.1 × 105 cfu (colony-forming units) per µg DNA, and the transformation efficiencies of PCR-assembled deletion constructs ranged from 3.2 ± 0.76 to 3.5 ± 0.42 × 104 cfu per µg DNA in the four tested strains. CONCLUSION: Artificial induction of genetic competence through overexpressing ComK Bsu in B. amyloliquefaciens completed the tasks of replicative plasmid delivery and gene knockout via direct transformation of PCR-generated deletion cassettes.


Assuntos
Bacillus amyloliquefaciens/genética , Plasmídeos/genética , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética
11.
Ann Med ; 56(1): 2301596, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38478750

RESUMO

BACKGROUND: Rapid Cycle Deliberate Practice (RCDP) has gained prominence in recent years as an innovative teaching method in simulation-based training for adult and pediatric emergency medical skills. However, its application in the training of forceps delivery skills among obstetrics and gynecology residents remains unexplored. This study aimed to assess the impact of RCDP in this domain. METHODS: Conducted in March 2021, this randomized controlled study involved 60 second-year obstetrics and gynecology residents undergoing standardized training. Participants were randomly assigned to the RCDP group or the traditional teaching method (TTM) group, each comprising 30 residents. The RCDP group followed the RCDP practice mode, while the TTM group adhered to conventional simulation teaching. Post-training assessment of operational proficiency was conducted immediately and after one year. Independent operational confidence and training satisfaction were evaluated through questionnaire surveys and the Satisfaction with Simulation Experience (SSE) scale. Data analysis utilized SPSS 23.0. RESULTS: The RCDP group displayed significantly higher immediate post-training forceps operation scores compared to the TTM group (92.00 [range: 90.00-94.00] vs. 88.00 [range: 86.75-92.00]; z = 3.79; p < .001). However, no significant difference emerged in forceps operation scores after one year (86.00 [range: 85.00-88.00] vs. 85.50 [range: 84.00-88.25]; z = 0.54; p = .59). The RCDP group exhibited notable performance improvement over the TTM group (z = 3.49; p < .001). Independent operation confidence showed no significant discrepancy (p > .05). Importantly, the RCDP group reported higher satisfaction scores, particularly in the Debriefing and Reflection subscale (44.00 [range: 43.00-45.00] vs. 41.00 [range: 41.50-43.00]; z = 5.24; p < .001), contributing to an overall superior SSE score (z = 4.74; p < .001). CONCLUSIONS: RCDP exhibits immediate efficacy in elevating forceps delivery skills among residents. However, sustained skill enhancement necessitates innovative approaches, while RCDP's value lies in tailored feedback and reflection for enriched medical education.


Rapid Cycle Deliberate Practice (RCDP) demonstrates immediate effectiveness in enhancing forceps delivery skills among obstetrics and gynecology residents, leading to improved immediate performance, which also increased their satisfaction with the teaching process and operational confidence.Long-term skill retention through RCDP appears limited, highlighting the importance of ongoing reinforcement to prevent skill decay and maintain proficiency.


Assuntos
Ginecologia , Internato e Residência , Treinamento por Simulação , Humanos , Competência Clínica , Ginecologia/educação , Instrumentos Cirúrgicos
12.
J Ethnopharmacol ; 333: 118418, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838926

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bronchitis is a respiratory disease characterized by a productive cough. Polygala tenuifolia Willd., commonly known as Yuan zhi, is a traditional Chinese herbal medicine used for relieving cough and removing phlegm. Despite its historical use, studies are lacking on the effectiveness of P. tenuifolia in treating bronchitis. Furthermore, the molecular mechanisms underlying the action of its bioactive compounds remain unknown. AIM OF THE STUDY: This study aims to identify the main bioactive compounds responsible for the effects of P. tenuifolia liquid extract (PLE) in treating bronchitis and to elucidate the associated molecular mechanisms. MATERIALS AND METHODS: The main chemical compounds in PLE were identified and determined using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The antitussive, expectorant and anti-inflammatory activities of PLE were evaluated in an ammonia-induced mouse cough model, a tracheal phenol red excretion mouse model, and a xylene-induced ear swelling mouse model, respectively. A network pharmacology analysis was conducted to investigate the associated gene targets, gene ontology, and KEGG pathways related to the main bioactives in PLE targeting bronchitis. PLE and its five bioactive compounds were assessed for their potential anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Western blot analysis was conducted to elucidate the associated molecular mechanisms. RESULTS: Thirty-seven compounds in PLE were identified, and twelve main compounds were further quantified in PLE using UPLC-MS/MS. PLE oral gavage administrations (0.6 and 0.12 mg/kg) for 7 days markedly reduced cough frequency, prolonged latency period of cough, reduced phlegm and inflammation in mice. The network pharmacology analysis identified 57 gene targets of PLE against bronchitis. The PI3K/AKT and MAPK signalling pathways were the top two modulated pathways. In RAW264.7 cells, PLE (12.5-50 µg/mL) significantly reduced cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), interleukin (IL)-1ß, IL-6 and tumor necrosis factor (TNF)-α. PLE downregulated LPS-elevated protein targets in both PI3K/AKT and MAPK signaling pathways. In PLE, tenuifolin, polygalaxanthone ⅠⅠⅠ, polygalasaponin ⅩⅩⅤⅢ, tenuifoliside B, and 3,6'-Disinapoyl sucrose, were identified as the top five core components responsible for treating bronchitis. These compounds were also found to modulate the protein targets in the PI3K/AKT and MAPK signalling pathways. CONCLUSIONS: This study demonstrated the potential therapeutic effects of PLE on bronchitis by reducing cough, phlegm and inflammation. The anti-inflammatory action and molecular mechanisms of the 5 main bioactive compounds in PLE were partly validated through the in vitro assays. The findings provide valuable insights into the mechanisms underlying the traditional use of PLE for bronchitis.

14.
Polymers (Basel) ; 16(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38475298

RESUMO

Intumescent flame retardants (IFRs) are mainly composed of ammonium polyphosphate (APP), melamine (ME), and some macromolecular char-forming agents. The traditional IFR still has some defects in practical application, such as poor compatibility with the matrix and low flame-retardant efficiency. In order to explore the best balance between flame retardancy and mechanical properties of flame-retardant polyformaldehyde (POM) composite, a biobased calcium magnesium bi-ionic melamine phytate (DPM) synergist was prepared based on renewable biomass polyphosphate phytic acid (PA), and its synergistic system with IFRs was applied to an intumescent flame-retardant POM system. POM/IFR systems can only pass the V-1 grade of the vertical combustion test (UL-94) if they have a limited oxygen index (LOI) of only 48.5%. When part of an IFR was replaced by DPM, the flame retardancy of the composite was significantly improved, and the POM/IFR/4 wt%DPM system reached the V-0 grade of UL-94, and the LOI reached 59.1%. Compared with pure POM, the PkHRR and THR of the POM/IFR/4 wt%DPM system decreased by 61.5% and 51.2%, respectively. Compared with the POM/IFR system, the PkHRR and THR of the POM/IFR/4 wt%DPM system were decreased by 20.8% and 27.5%, respectively, and carbon residue was increased by 37.2%. The mechanical properties of the composite also showed a continuous upward trend with the increase in DPM introduction. It is shown that the introduction of DPM not only greatly reduces the heat release rate and heat release amount of the intumescent flame-retardant POM system, reducing the fire hazard, but it also effectively improves the compatibility between the filler and the matrix and improves the mechanical properties of the composite. It provides a new approach for developing a new single-component multifunctional flame retardant or synergist for intumescent flame-retardant POM systems.

15.
iScience ; 27(2): 108941, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38333708

RESUMO

The significant anatomical changes in large intestine of germ-free (GF) mice provide excellent material for understanding microbe-host crosstalk. We observed significant differences of GF mice in anatomical and physiological involving in enlarged cecum, thinned mucosal layer and enriched water in cecal content. Furthermore, integration analysis of multi-omics data revealed the associations between the structure of large intestinal mesenchymal cells and the thinning of the mucosal layer. Increased Aqp8 expression in GF mice may contribute to enhanced water secretion or altered hydrodynamics in the cecum. In addition, the proportion of epithelial cells, nutrient absorption capacity, immune function and the metabolome of cecum contents of large intestine were also significantly altered. Together, this is the first systematic study of the transcriptome and metabolome of the cecum and colon of GF mice, and these findings contribute to our understanding of the intricate interactions between microbes and the large intestine.

16.
Insect Sci ; 30(6): 1677-1688, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36752392

RESUMO

Drosophila sodium channel 1 (DSC1) encodes a voltage-gated divalent cation channel that mediates neuronal excitability in insects. Previous research revealed that DSC1 knockout Drosophila melanogaster conferred different susceptibility to insecticides, which indicated the vital regulation role of DSC1 under insecticide stress. Haedoxan A (HA) is a lignan compound isolated from Phryma leptostachya, and we found that HA has excellent insecticidal activity and is worthy of further study as a botanical insecticide. Herein, we performed bioassay and electrophysiological experiments to test the biological and neural changes in the larval Drosophila with/without DSC1 knockout in response to HA. Bioassay results showed that knockout of DSC1 reduced the sensitivity to HA in both w1118 (a common wild-type strain in the laboratory) and parats1 (a pyrethroid-resistant strain) larvae. Except for parats1 /DSC1-/- , electrophysiology results implicated that HA delayed the decay rate and increased the frequency of miniature excitatory junctional potentials of Drosophila from w1118 , parats1 , and DSC1-/- strains. Moreover, the neuromuscular synapse excitatory activities of parats1 /DSC1-/- larvae were more sensitive to HA than DSC1-/- larvae, which further confirmed the functional contribution of DSC1 to neuronal excitability. Collectively, these results indicated that the DSC1 channel not only regulated the insecticidal activity of HA, but also maintained the stability of neural circuits through functional interaction with voltage-gated sodium channels. Therefore, our study provides useful information for elucidating the regulatory mechanism of DSC1 in the neural system of insects involving the action of HA derived from P. leptostachya.


Assuntos
Proteínas de Drosophila , Inseticidas , Canais de Sódio Disparados por Voltagem , Animais , Drosophila melanogaster/fisiologia , Drosophila/metabolismo , Inseticidas/farmacologia , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Canais de Sódio Disparados por Voltagem/genética
17.
J Agric Food Chem ; 71(2): 1162-1169, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36621524

RESUMO

2,3,5-Trimethylhydroquinone (2,3,5-TMHQ) is the key precursor in the synthesis of vitamin E. It is still a major challenge to produce 2,3,5-TMHQ under mild reaction conditions by chemical methods. The monooxygenase system MpdAB can specifically catalyze the conversion of 2,3,6-trimethylphenol (2,3,6-TMP) to 2,3,5-TMHQ. However, the weak catalytic capacity of wild-type MpdA and the cytotoxicity of the substrate limited the production efficiency of 2,3,5-TMHQ. Here, homologous modeling and saturation mutation were performed to increase the catalytic activity of MpdA. Two variants, L128A and L128K, with higher activity toward 2,3,6-TMP (1.86-1.87-fold) were obtained. On the other hand, an evolved strain B5-4M-evolved with enhanced resistance to 2,3,6-TMP (8.15-fold higher for 1000 µM 2,3,6-TMP) was obtained through adaptive laboratory evolution. Subsequently, a 5.29-fold (or 4.87-fold) improvement in 2,3,5-TMHQ production was achieved by a strain B5-4M-evolved harboring L128K (or L128A) and MpdB, in comparison with that of the wild type (strain B5-4M expressing MpdAB). This study provides better genetic resources for producing 2,3,5-TMHQ and proves that the synthesis efficiency of 2,3,5-TMHQ can be improved through enzyme modification and adaptive laboratory evolution.


Assuntos
Compostos de Diazônio , Piridinas , Vitamina E
18.
Ultrason Sonochem ; 94: 106322, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36774672

RESUMO

In this study, the influence of ultrasound-assisted resting at different power on the rheological properties, water distribution and structural characteristics of dough with 50 % surimi as well as the texture, cooking and microstructure characteristics of the surimi-wheat noodles were investigated. Compared with the fermentation control (FC) noodles, the microstructure, cooking and texture characteristics of noodles (≤24.00 W/L) were significantly (p < 0.05) improved after ultrasonic treating. As the increasing of ultrasonic power, compared to FC, the creep strain, recovery strain, semi-bound water, and free sulfhydryl (SH) contents of surimi-wheat dough decreased at first and then increased significantly (p < 0.05). The α-helix and ß-turn content of dough increased at first and then decreased after ultrasonic treatment, while the ß-sheet was reversed. The surimi-wheat dough network structure was improved by ultrasonic treatment, with the densest and continuous pore size in 21.33 W/L, but the dough structure was broken and loose (>21.33 W/L), which consisted of the hardness, elasticity, chewiness, resistant and cooked quality of surimi-wheat noodles. This work elucidated the effect of ultrasonic power on the performance of surimi-wheat dough, and the optimal ultrasound power was obtained, thereby improving the nutritional properties and the quality of surimi-wheat noodles.


Assuntos
Qualidade dos Alimentos , Triticum , Triticum/química , Farinha/análise , Culinária , Água
19.
Front Plant Sci ; 14: 1147932, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465385

RESUMO

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (R-SNAREs) mainly promoted the assembly of the SNARE complex to drive the final membrane fusion step of membrane transport. Previous research on R-SNAREs has mainly focused on development and growth and has rarely been involved in abiotic stress, especially in cotton. Here, we performed a comprehensive analysis of R-SNARE genes in upland cotton. In total, 51 Gh-R-SNARE genes across six phylogenetic groups were unevenly distributed on 21 chromosomes. Cis elements related to plant growth and response to abiotic stress responses were found in the promoter region of Gh-R-SNAREs. Nine Gh-R-SNARE genes were obviously upregulated under drought stress conditions by RNA-seq and qRT-PCR analysis. Among them, GhVAMP72l might be the key candidate gene contributing to drought stress tolerance in cotton by virus-induced gene silencing (VIGS) assay. These results provide valuable insights for the functional analysis of cotton R-SNAREs in response to drought stress and highlight potential beneficial genes for genetic improvement and breeding in cotton.

20.
Polymers (Basel) ; 15(3)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36771838

RESUMO

Ammonium polyphosphate (APP) was successfully modified by a titanate coupling agent which was compounded with benzoxazine (BOZ) and melamine (ME) to become a new type of intumescent flame retardant (Ti-IFR). Ti-IFR and CaCO3 as synergists were utilized to modify polyoxymethylene (POM), and the flame-retardant properties and mechanism of the composites were analyzed by vertical combustion (UL-94), limiting oxygen index (LOI), TG-IR, and cone calorimeter (Cone), etc. The results show that Ti-IFR can enhance the gas phase flame retardant effect, while CaCO3 further strengthens the barrier effect in the condensed phase. When they were used together, they can exert their performance, respectively, at the same time showing excellent synergistic effect. The FR-POM composite with 29% Ti-IFR and 1% CaCO3 can pass the UL-94 V0 level. The LOI reaches 58.2%, the average heat release (Av HRR) is reduced by 81.1% and the total heat release (THR) is decreased by 35.3%.

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