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1.
MycoKeys ; 106: 23-41, 2024.
Article de Anglais | MEDLINE | ID: mdl-38910875

RÉSUMÉ

Morphological and phylogenetic analyses on samples of Xylaria species associated with fallen fruits from China were carried out, and two new species were described, namely X.aleuriticola and X.microcarpa. Xylariaaleuriticola is found on fallen fruits of Aleuritesmoluccana, and characterized by stromata dichotomously branched several times with long acute sterile apices, fertile parts roughened with perithecia and tomentose, and ellipsoid to fusiform ascospores. Xylariamicrocarpa differs in its very small stromata with dark brown tomentum, light brown ascospores with an inconspicuous straight germ slit, and grows on leguminous pods. The differences between the new species and morphologically similar species are discussed. Phylogenetic analyses on ITS-RPB2-TUB sequences confirmed that the two species are clearly separated from other species of the genus Xylaria. Xylarialiquidambaris is reported as a new record from China. A key to the Xylaria species associated with fallen fruits and seeds reported from China is provided to facilitate future studies of the genus.

2.
Poult Sci ; 103(8): 103961, 2024 Jun 08.
Article de Anglais | MEDLINE | ID: mdl-38941761

RÉSUMÉ

Salmonella and Campylobacter are major foodborne pathogens that cause outbreaks associated with contaminated chicken liver. Proper cooking is necessary to avoid the risk of illness to consumers. This study tested the thermal inactivation of a 4-strain Salmonella cocktail and a 3-strain Campylobacter cocktail in chicken livers separately at temperatures ranging from 55.0 to 62.5°C. Inoculated livers were sealed in aluminum cells and immersed in a water bath. The decimal reduction time (D-values) of Salmonella in chicken livers were 9.01, 2.36, 0.82, and 0.23 min at 55.0, 57.5, 60.0, and 62.5°C, respectively. The D-values of Campylobacter ranged from 2.22 min at 55.0°C to 0.19 min at 60.0°C. Salmonella and Campylobacter had similar z-values in chicken livers of 4.8 and 4.6°C, respectively. Chicken livers can be heated to internal temperatures of 70.0 to 73.9°C for at least 1.6 to 0.2 s to achieve a 7-log reduction of Salmonella. Validation tests demonstrated that heating chicken livers to internal temperatures of 70.0 to 73.9°C for 2 to 0 s resulted in a reduction of Salmonella exceeding 7 logs. Collectively, these data show that Salmonella exhibits higher heat resistance than Campylobacter in chicken livers. Therefore, Salmonella could be considered as the target pathogen when designing thermal treatments or cooking instructions for liver products. These findings will aid in designing effective thermal processing for both industrial and home cooking to eliminate Salmonella and Campylobacter, ensuring consumer safety when consuming chicken liver products.

3.
Int J Biol Macromol ; 271(Pt 1): 132415, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38759858

RÉSUMÉ

OBJECTIVE: We aimed to investigate the effect of Lycium barbarum polysaccharide (LBP) on the proliferation and differentiation of osteoblasts in postmenopausal individuals with osteoporosis using in vitro cell experiments. METHODS: We assessed the effect of long-term LBP consumption on the intestinal metabolites of individuals using a simulation of the human intestinal microbiota ecosystem. We also tested the capacity of LBP in proliferating MC3T3-E1 cells using the cell counting kit-8 (CCK-8) method and analyzed the effect of intestinal metabolites on the osteogenic differentiation of MC3T3-E1 cells by testing bone metabolism viability with relevant indicators. RESULTS: The level of short-chain fatty acids (SCFAs) significantly increased (p < 0.05), and the concentrations of acetic acid, propionic acid, and butyric acid all showed an upward trend after the treatment using LBP. At appropriate concentrations, the fermentation supernatant can enhance osteoblast proliferation by significantly increasing the active expression of bone-alkaline phosphatase (B-ALP) and osteocalcin (OCN) in osteoblasts (p < 0.05). CONCLUSION: By modulating the metabolites of intestinal microbiota, production of SCFAs, the prebiotic properties of LBP can enhance osteoblast differentiation through in vitro simulation experiment and cell-based assay.


Sujet(s)
Différenciation cellulaire , Prolifération cellulaire , Médicaments issus de plantes chinoises , Ostéoblastes , Ostéoporose post-ménopausique , Ostéoblastes/effets des médicaments et des substances chimiques , Ostéoblastes/métabolisme , Humains , Différenciation cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Médicaments issus de plantes chinoises/pharmacologie , Femelle , Souris , Animaux , Ostéoporose post-ménopausique/traitement médicamenteux , Ostéoporose post-ménopausique/métabolisme , Acides gras volatils/métabolisme , Ostéogenèse/effets des médicaments et des substances chimiques , Microbiome gastro-intestinal/effets des médicaments et des substances chimiques , Phosphatase alcaline/métabolisme , Lignée cellulaire , Ostéocalcine/métabolisme
4.
Mater Today Bio ; 26: 101093, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38818528

RÉSUMÉ

The incidence of chronic wound healing is promoted by the growing trend of elderly population, obesity, and type II diabetes. Although numerous wound dressings have been studied over the years, it is still challenging for many wound dressings to perfectly adapt to the healing process due to the dynamic and complicated wound microenvironment. Aiming at an optimal reproduction of the physiological environment, multifunctional electrospinning nanofibrous membranes (ENMs) have emerged as a promising platform for the wound treatment owing to their resemblance to extracellular matrix (ECM), adjustable preparation processes, porousness, and good conformability to the wound site. Moreover, profiting from the booming development of human-machine interaction and artificial intelligence, a next generation of intelligent electrospinning nanofibrous membranes (iENMs) based wound dressing substrates that could realize the real-time monitoring of wound proceeding and individual-based wound therapy has evoked a surge of interest. In this regard, general wound-related biomarkers and process are overviewed firstly and representative iENMs stimuli-responsive materials are briefly summarized. Subsequently, the emergent applications of iENMs for the wound healing are highlighted. Finally, the opportunities and challenges for the development of next-generation iENMs as well as translating iENMs into clinical practice are evaluated.

5.
Sci Rep ; 14(1): 12280, 2024 05 29.
Article de Anglais | MEDLINE | ID: mdl-38811827

RÉSUMÉ

Loss of the tumor suppressor PTEN homolog daf-18 in Caenorhabditis elegans (C. elegans) triggers diapause cell division during L1 arrest. While prior studies have delved into established pathways, our investigation takes an innovative route. Through forward genetic screening in C. elegans, we pinpoint a new player, F12E12.11, regulated by daf-18, impacting cell proliferation independently of PTEN's typical phosphatase activity. F12E12.11 is an ortholog of human estradiol 17-beta-dehydrogenase 8 (HSD17B8), which converts estradiol to estrone through its NAD-dependent 17-beta-hydroxysteroid dehydrogenase activity. We found that PTEN engages in a physical interplay with HSD17B8, introducing a distinctive suppression mechanism. The reduction in estrone levels and accumulation of estradiol may arrest tumor cells in the G2/M phase of the cell cycle through MAPK/ERK. Our study illuminates an unconventional protein interplay, providing insights into how PTEN modulates tumor suppression by restraining cell division through intricate molecular interactions.


Sujet(s)
Protéines de Caenorhabditis elegans , Caenorhabditis elegans , Prolifération cellulaire , Phosphohydrolase PTEN , Phosphohydrolase PTEN/métabolisme , Phosphohydrolase PTEN/génétique , Animaux , Caenorhabditis elegans/métabolisme , Caenorhabditis elegans/génétique , Protéines de Caenorhabditis elegans/métabolisme , Protéines de Caenorhabditis elegans/génétique , Humains , 17-Hydroxysteroid dehydrogenases/métabolisme , 17-Hydroxysteroid dehydrogenases/génétique , Oestradiol/métabolisme , Oestrone/métabolisme
6.
Front Med (Lausanne) ; 11: 1363979, 2024.
Article de Anglais | MEDLINE | ID: mdl-38606159

RÉSUMÉ

Introduction: Acute liver failure (ALF) is defined as acute loss of liver function leading to hepatic encephalopathy associated with a high risk of patient death. Brain injury markers in serum and tissue can help detect and monitor ALF-associated brain injury. This study compares different brain injury parameters in plasma and tissue along with the progression of ALF. Method: ALF was induced by performing an 85% liver resection. Following the resection, animals were recovered and monitored for up to 48 h or until reaching the predefined endpoint of receiving standard medical therapy (SMT). Blood and serum samples were taken at Tbaseline, T24, and upon reaching the endpoint (Tend). Control animals were euthanized by exsanguination following plasma sampling. Postmortem brain tissue samples were collected from the frontal cortex (FCTx) and cerebellum (Cb) of all animals. Glial fibrillary acidic protein (GFAP) and tau protein and mRNA levels were quantified using ELISA and qRT-PCR in all plasma and brain samples. Plasma neurofilament light (NFL) was also measured using ELISA. Results: All ALF animals (n = 4) were euthanized upon showing signs of brain herniation. Evaluation of brain injury biomarkers revealed that GFAP was elevated in ALF animals at T24h and Tend, while Tau and NFL concentrations were unchanged. Moreover, plasma glial fibrillary acidic protein (GFAP) levels were negatively correlated with total protein and positively correlated with both aspartate transaminase (AST) and alkaline phosphatase (AP). Additionally, lower GFAP and tau RNA expressions were observed in the FCTx of the ALF group but not in the CB tissue. Conclusion: The current large animal study has identified a strong correlation between GFAP concentration in the blood and markers of ALF. Additionally, the protein and gene expression analyses in the FCTx revealed that this area appears to be susceptible, while the CB is protected from the detrimental impacts of ALF-associated brain swelling. These results warrant further studies to investigate the mechanisms behind this process.

7.
Molecules ; 29(6)2024 Mar 17.
Article de Anglais | MEDLINE | ID: mdl-38542974

RÉSUMÉ

PETase exhibits a high degradation activity for polyethylene terephthalate (PET) plastic under moderate temperatures. However, the effect of non-active site residues in the second shell of PETase on the catalytic performance remains unclear. Herein, we proposed a crystal structure- and sequence-based strategy to identify the key non-active site residue. D186 in the second shell of PETase was found to be capable of modulating the enzyme activity and stability. The most active PETaseD186N improved both the activity and thermostability with an increase in Tm by 8.89 °C. The PET degradation product concentrations were 1.86 and 3.69 times higher than those obtained with PETaseWT at 30 and 40 °C, respectively. The most stable PETaseD186V showed an increase in Tm of 12.91 °C over PETaseWT. Molecular dynamics (MD) simulations revealed that the D186 mutations could elevate the substrate binding free energy and change substrate binding mode, and/or rigidify the flexible Loop 10, and lock Loop 10 and Helix 6 by hydrogen bonding, leading to the enhanced activity and/or thermostability of PETase variants. This work unraveled the contribution of the key second-shell residue in PETase in influencing the enzyme activity and stability, which would benefit in the rational design of efficient and thermostable PETase.


Sujet(s)
Hydrolases , Téréphtalate polyéthylène , Hydrolases/composition chimique , Téréphtalate polyéthylène/composition chimique , Simulation de dynamique moléculaire , Mutation
8.
BMJ Open ; 14(2): e077765, 2024 Feb 21.
Article de Anglais | MEDLINE | ID: mdl-38387981

RÉSUMÉ

OBJECTIVES: This study aims to investigate factors with a significant influence on deceased organ donation rates in Organisation for Economic Co-operation and Development (OECD) countries and determine their relative importance. It seeks to provide the necessary data to facilitate the development of more efficient strategies for improving deceased organ donation rates. DESIGN: Retrospective study. SETTING: Publicly available secondary annual data. PARTICIPANTS: The study includes 36 OECD countries as panel members for data analysis. OUTCOME MEASURES: Multivariable panel data regression analysis was employed, encompassing data from 2010 to 2018 for all investigated variables in the included countries. RESULTS: The following variables had a significant influence on deceased organ donation rates: 'opt-in' system (ß=-4.734, p<0.001, ref: 'opt-out' system), only donation after brain death (DBD) donors allowed (ß=-4.049, p=0.002, ref: both DBD and donation after circulatory death (DCD) donors allowed), number of hospital beds per million population (pmp) (ß=0.002, p<0.001), total healthcare employment pmp (ß=-0.00012, p=0.012), World Giving Index (ß=0.124, p=0.008), total tax revenue as a percentage of gross domestic product (ß=0.312, p=0.009) and percentage of population aged ≥65 years (ß=0.801, p<0.001) as well as high education population in percentage (ß=0.118, p=0.017). CONCLUSIONS: Compared with the promotion of socioeconomic factors with a positive significant impact on deceased organ donation rates, the following policies have been shown to significantly increase rates of deceased organ donation, which could be further actively promoted: the adoption of an 'opt-out' system with presumed consent for deceased organ donation and the legal authorisation of both DBD and DCD for transplantation.


Sujet(s)
Transplantation d'organe , Acquisition d'organes et de tissus , Humains , Organisation de coopération et de développement économiques , Études rétrospectives , Donneurs de tissus
9.
Integr Med Res ; 13(1): 101021, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38379605

RÉSUMÉ

Background: The integration of acupuncture with intramuscular injection of diclofenac sodium can expedite the onset of analgesia in treating acute renal colic caused by urolithiasis. However, it remains unclear whether acupuncture can accelerate pain relief constantly until complete remission. This study aimed to explore the extent to which acupuncture can expedite the onset time of response or complete pain relief in treating acute renal colic, and the predictive value of patient characteristics for treatment efficacy. Methods: This secondary analysis utilized data from a prior randomized controlled trial. Eighty patients with acute renal colic were randomly assigned 1:1 to the acupuncture group or the sham acupuncture group. After intramuscular injection of diclofenac sodium, acupuncture or sham acupuncture was delivered to patients. The outcomes included time to response (at least a 50 % reduction in pain) and complete pain relief. Between-group comparison under the 2 events was estimated by Kaplan-Meier methodology. Subgroup analysis was performed utilizing the Cox proportional hazards model. Results: The median response time and complete pain relief time in the acupuncture group were lower than those in the sham acupuncture group (5 vs 30 min, Log Rank P < 0.001; 20 min vs not observed, Log Rank P < 0.001, respectively). Hazard Ratios (HRs) for response across all subgroups favored the acupuncture group. All HRs for complete pain relief favored acupuncture, expect large stone and moderate pain at baseline. No interaction was found in either event. Conclusion: Acupuncture can accelerate the response time and complete pain relief time for patients with acute renal colic, with the efficacy universally. Trial registration: This study has been registered at Chinese Clinical Trial Registry: ChiCTR1900025202.

10.
ACS Appl Mater Interfaces ; 16(2): 2296-2308, 2024 Jan 17.
Article de Anglais | MEDLINE | ID: mdl-38189244

RÉSUMÉ

Covalent triazine frameworks (CTFs) have recently emerged as an efficient class of photocatalysts due to their structural diversity and excellent stability. Nevertheless, the synthetic reactions of CTFs have usually suffered from poor reversibility, resulting in a low crystallinity of the materials. Here, we report the introduction of methoxy groups on the monomer 2,5-diphenylthiazolo[5,4-d]thiazole to reinforce interlayer π-π interactions of the resulting donor-acceptor type CTFs, which improved crystallinity, further increasing the visible light absorption range and allowing for efficient separation and transport of carriers. The morphology is strongly correlated to the wettability, which has a significant impact on the mass transfer capacity and photocatalytic activity in the photocatalytic reaction. To further improve crystallinity and photocatalytic activity, CTF-NWU-T3 photocatalysts in a bowl shape were prepared using a SiO2 template. The energy band structure, photocatalytic hydrogen evolution, and pollutant degradation efficiency of involved materials were investigated. The donor-acceptor type CTF-NWU-T3 with a bowl-shaped morphology, synthesized using the template method and the introduction of methoxy groups, exhibited an excellent photocatalytic hydrogen production rate of 32064 µmol·h-1·g-1. This study highlights the significance of improving donor-acceptor interactions and increasing the dispersibility of catalyst particles in dispersion to enhance the photocatalytic activity of heterogeneous photocatalysts.

11.
Lancet ; 403(10422): 144, 2024 Jan 13.
Article de Anglais | MEDLINE | ID: mdl-38218609
12.
ACS Appl Mater Interfaces ; 16(3): 3809-3818, 2024 Jan 24.
Article de Anglais | MEDLINE | ID: mdl-38211320

RÉSUMÉ

Narrowband blue emitters are indispensable in achieving ultrahigh-definition OLED displays that satisfy the stringent BT 2020 standard. Hereby, a series of bis-tridentate Ir(III) complexes bearing electron-deficient imidazo[4,5-b]pyridin-2-ylidene carbene coordination fragments and 2,6-diaryloxy pyridine ancillary groups were designed and synthesized. They exhibited deep blue emission with quantum yields of up to 89% and a radiative lifetime of 0.71 µs in the DPEPO host matrix, indicating both the high efficiency and excellent energy transfer process from the host to dopant. The OLED based on Irtb1 showed an emission at 468 nm with a maximum external quantum efficiency (EQE) of 22.7%. Moreover, the hyper-OLED with Irtb1 as a sensitizer for transferring energy to terminal emitter v-DABNA exhibited a narrowband blue emission at 472 nm and full width at half-maximum (FWHM) of 24 nm, a maximum EQE of 23.5%, and EQEs of 19.7, 16.1, and 12.9% at a practical brightness of 100, 1000, and 5000 cd/m2, respectively.

13.
Environ Sci Pollut Res Int ; 31(8): 11428-11452, 2024 Feb.
Article de Anglais | MEDLINE | ID: mdl-38183545

RÉSUMÉ

Microplastic (MP) is ubiquitous in the environment which appeared as an immense intimidation to human and animal health. The plastic fragments significantly polluted the ocean, fresh water, food chain, and other food items. Inadequate maintenance, less knowledge of adverse influence along with inappropriate usage in addition throwing away of plastics items revolves present planet in to plastics planet. The present study aims to focus on the recognition and advance detection technologies for MPs and the adverse effects of micro- and nanoplastics on human health. MPs have rigorous adverse effect on human health that leads to condensed growth rates, lessened reproductive capability, ulcer, scrape, and oxidative nervous anxiety, in addition, also disturb circulatory and respiratory mechanism. The detection of MP particles has also placed emphasis on identification technologies such as scanning electron microscopy, Raman spectroscopy, optical detection, Fourier transform infrared spectroscopy, thermo-analytical techniques, flow cytometry, holography, and hyperspectral imaging. It suggests that further research should be explored to understand the source, distribution, and health impacts and evaluate numerous detection methodologies for the MPs along with purification techniques.


Sujet(s)
Microplastiques , Polluants chimiques de l'eau , Animaux , Humains , Matières plastiques/composition chimique , Polluants chimiques de l'eau/analyse , Surveillance de l'environnement , Eau douce
14.
Sci Total Environ ; 912: 169214, 2024 Feb 20.
Article de Anglais | MEDLINE | ID: mdl-38092203

RÉSUMÉ

Sodium carboxymethyl cellulose (CMCNa) application has been a promising approach to improve soil quality. The purpose of this study was to explore the effects of CMC-Na on soil infiltration, evaporation, water-salt distribution, crop growth, water use efficiency and net profit (Net) in a coastal saline-alkali soil maize-wheat cropping system (MWCS). Five CMC-Na application amounts (0, 0.1, 0.2, 0.4 and 0.6 g kg-1) were designed for the soil column experiment indoor, and five CMC-Na application amounts were used in 2019-2020 field experiment (CK: 0, C10: 10 kg ha-1, C20: 10 kg ha-1, C30: 10 kg ha-1 and C50: 10 kg ha-1), No treatment will be applied in 2021. The results showed that (1) CMC-Na treatment reduced soil cumulative infiltration, infiltration rate, daily evaporation, and cumulative evaporation. (2) After the application of CMCNa, the average soil water storage (SWS) in the 0-60 cm soil layer increased, and soil salinity (SSC) decreased in most treatments. (3) In the 2019-2020, the maize aboveground biomass (B), yield (Y) and water use efficiency (WUE) were the highest under the C20 and C30 treatments, which were 15.24 and 15.32 t ha-1, 5.67 and 5.49 t ha-1 and 1.74 and 1.52 kg ha-1 mm-1, respectively, and the wheat under C30 treatment is the highest, which were 10.98 t ha-1, 5.27 t ha-1 and 1.78 kg ha-1 mm-1. (4) A dose of 25.5 kg ha-1 and 38.9 kg ha-1 was recommended as the most optimal CMC-Na application for maize and wheat in coastal saline alkali soil, respectively.


Sujet(s)
Sol , Triticum , Zea mays , Carboxyméthylcellulose de sodium , Alcalis , Eau , Sodium
15.
Aquat Toxicol ; 266: 106775, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-38043483

RÉSUMÉ

Water pollution induced by antibiotics has garnered considerable concern, necessitating urgent and effective removal methods. This study focused on exploring ciprofloxacin (CIP) removal by duckweed and assessing CIP bioaccumulation and toxic effects within duckweed under varying dissolved organic matter categories, pH levels, and nutrient (nitrogen (N) and phosphorus (P)) levels. The results revealed the proficient and rapid elimination of CIP from water by duckweed, resulting in 86.17 % to 92.82 % removal efficiency at the end of the 7-day experiment. Across all exposure groups, varying degrees of CIP bioaccumulation in duckweed were evident, with uptake established as a primary pathway for CIP elimination within this plant. Additionally, five CIP metabolites were identified in duckweed tissues. Interestingly, the presence of humic acid (HA) and fulvic acid (FA) reduced CIP absorption by duckweed, with FA yielding a more pronounced impact. Optimal CIP removal was recorded at a pH of 7.5, while duckweed displayed heightened physiological stress induced by CIP at pH 8.5. Although the influence of N and P concentrations on CIP removal by duckweed was modest, excessive N and P levels intensified the physiological strain of CIP on duckweed.


Sujet(s)
Araceae , Polluants chimiques de l'eau , Ciprofloxacine/toxicité , Ciprofloxacine/analyse , Matière organique dissoute , Bioaccumulation , Polluants chimiques de l'eau/toxicité , Antibactériens/toxicité , Nutriments , Araceae/métabolisme , Concentration en ions d'hydrogène
16.
Sci Rep ; 13(1): 22938, 2023 Dec 22.
Article de Anglais | MEDLINE | ID: mdl-38129470

RÉSUMÉ

In this paper, a thick plate structural mechanical model was established for the hard-thick rock strata in the Ordos region, which was characterized by the occurrence of high-energy strong earthquakes caused by the fracture of hard-thick rock strata. Subsequently, based on Vlasov's theory, the evolution process of hard-thick rock strata was analyzed. And the paper validated the analysis results using high-energy mine earthquake and surface subsidence data. The following conclusions were drawn: (1) The hard-thick strata in the cretaceous system will not be broken during the advancing and mining process of the test panel of the Shilawusu coal mine. (2) When the test panel is mined to a distance of two panel widths, no fracture occurred in the lower part of the hard-thick strata, because no separated space was formed. (3) When the test panel was advanced to about 856 m, the hard-thick strata have fractured in a vertical direction. (4) No high-energy mine earthquake event has occurred during mining at test panel, and the amount of surface subsidence is approximately 200 mm. (5) In the mining at test panel, two high-energy mining earthquakes occurred at 837 m, 1153 m away from the initial position of the panel, respectively, and the maximum amount of surface subsidence increased to 1397 mm, which accords with the results of the first and periodic breaks calculated by theory. The research results of this paper are of guiding significance for the study of the breaking law of hard-thick strata under similar engineering geological conditions and disaster pre-control.

17.
Biomimetics (Basel) ; 8(8)2023 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-38132520

RÉSUMÉ

Surface engineering of nanoparticles has been widely used in biosensing and assays, where sensitivity was mainly limited by plasmonic colour change or electrochemical responses. Here, we report a novel biomimetic sensing strategy involving protein-modified gold nanoparticles (AuNPs), where the modulation strategy was inspired by gastropods in inhibition of coffee-ring effects in their trail-followings. The so-called coffee-ring effect presents the molecular behaviour of AuNPs to a macroscopic ring through aggregation, and thus greatly improves sensitivity. The assay relies upon the different assembly patterns of AuNPs against analytes, resulting in the formation or suppression of coffee-ring effects by the different surface engineering of AuNPs by proteins and peptides. The mechanism of the coffee-ring formation process is examined through experimental characterizations and computational simulations. A practical coffee-ring effect assay is developed for a proof-of-concept target, amyloid ß (1-42), which is a typical biomarker of Alzheimer's disease. A novel quasi-titrimetric protocol is constructed for quantitative determination of the target molecule. The assay shows excellent selectivity and sensitivity for the amyloid ß monomer, with a low detection limit of 20 pM. Combined with a fluorescent staining technique, the assay is designed as a smart sensor for amyloid ß detection and fibrillation evaluation in rat cerebrospinal fluids, which is a potential point-of-care test for Alzheimer's disease. Connections between amyloid fibrillation and different courses of brain ischaemia are also studied, with improved sensitivity, lower sample volumes that are required, convenience for rapid detection, and point-of-care testing.

18.
Sci Rep ; 13(1): 20175, 2023 11 17.
Article de Anglais | MEDLINE | ID: mdl-37978264

RÉSUMÉ

Besides the many advantages of oral drug administration, challenges like premature drug degradation and limited bioavailability in the gastro-intestinal tract (GIT) remain. A prolonged residence time in the GIT is beneficial for enhancing the therapeutic outcome when treating diseases associated with an increased intestinal clearance rate, like inflammatory bowel disease (IBD). In this study, we synthesized rod-shaped mesoporous silica nanoparticles (MSNs) functionalized with polyethylene glycol (PEG) or hyaluronic acid (HA) and investigated their bio-distribution upon oral administration in vivo. The negatively charged, non-toxic particles showed different accumulation behavior over time in healthy mice and in mice with dextran sulfate sodium (DSS)-induced intestinal inflammation. PEGylated particles were shown to accumulate in the lower intestinal tract of healthy animals, whereas inflammation promoted retention of HA-functionalized particles in this area. Overall systemic absorption was low. However, some particles were detected in organs of mice with DSS-induced colitis, especially in the case of MSN-PEG. The in vivo findings were connected to surface chemistry-related differences in particle adhesion on Caco-2/Raji and mucus-producing Caco-2/Raji/HT29 cell co-culture epithelial models in vitro. While the particle adhesion behavior in vivo was mirrored in the in vitro results, this was not the case for the resorption results, suggesting that the in vitro model does not fully reflect the erosion of the inflamed epithelial tissue. Overall, our study demonstrates the possibility to modulate accumulation and retention of MSNs in the GIT of mice with and without inflammation through surface functionalization, which has important implications for the formulation of nanoparticle-based delivery systems for oral delivery applications.


Sujet(s)
Colite , Nanoparticules , Humains , Souris , Animaux , Systèmes de délivrance de médicaments/méthodes , Cellules Caco-2 , Silice , Colite/induit chimiquement , Colite/traitement médicamenteux , Polyéthylène glycols , Inflammation , Sulfate dextran
19.
Ecotoxicol Environ Saf ; 268: 115687, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37976926

RÉSUMÉ

Accumulation of the heavy metal Cadmium (Cd) in the ovaries and placenta can affect the structure and function of these organs and induce female reproductive toxicity. This toxicity may be due to Cd's similarity to estrogen and its ability to disrupt endocrine systems. However, the exact molecular mechanism by which Cd causes reproductive toxicity at the transcriptome level remains poorly understood. Hence, this study aimed to observe Cd-induced reproductive damage at the gene level, scrutinize the repercussions of Cd exposure on oogenesis, and explicate the putative pathogenesis of Cd-induced oogenesis based on Caenorhabditis elegans (C. elegans) as an in vivo model. The results showed that Cd exposure significantly decreased the number of offspring and prolonged the reproductive span of C. elegans. Cd exposure also reduced the number of cells in mitosis and the pachytene and diakinesis stages of meiosis, thereby disrupting oogenesis. Combined with transcriptional sequencing and bioinformatics analysis, a total of 3167 DEmRNAs were identified. Regarding gene expression, cul-6, mum-2, and vang-1 were found to be related to Cd-induced reproductive toxicity, and their competing endogenous RNA networks were constructed. We observed that mutations of mom-2 and vang-1 in the Wnt pathway could induce susceptibility to Cd-caused meiosis injury. In conclusion, the results indicated that Cd could impair the oogenesis of C. elegans and the Wnt pathway might serve as a protective mechanism against Cd reproductive toxicity. These findings contribute to a better understanding of the damaging effects and molecular biological mechanisms of Cd on the human reproductive system.


Sujet(s)
Protéines de Caenorhabditis elegans , Métaux lourds , Animaux , Femelle , Humains , Caenorhabditis elegans , Cadmium/métabolisme , ARN/métabolisme , Ovogenèse/génétique , Métaux lourds/métabolisme , Protéines de Caenorhabditis elegans/génétique , Protéines de Caenorhabditis elegans/métabolisme
20.
J Am Chem Soc ; 145(46): 25283-25292, 2023 11 22.
Article de Anglais | MEDLINE | ID: mdl-37857329

RÉSUMÉ

DNA-encoded chemical library (DEL) has been extensively used for lead compound discovery for decades in academia and industry. Incorporating an electrophile warhead into DNA-encoded compounds recently permitted the discovery of covalent ligands that selectively react with a particular cysteine residue. However, noncysteine residues remain underexplored as modification sites of covalent DELs. Herein, we report the design and utility of tyrosine-targeting DELs of 67 million compounds. Proteome-wide reactivity analysis of tyrosine-reactive sulfonyl fluoride (SF) covalent probes suggested three enzymes (phosphoglycerate mutase 1, glutathione s-transferase 1, and dipeptidyl peptidase 3) as models of tyrosine-targetable proteins. Enrichment with SF-functionalized DELs led to the identification of a series of tyrosine-targeting covalent inhibitors of the model enzymes. In-depth mechanistic investigation revealed their novel modes of action and reactive ligand-accessible hotspots of the enzymes. Our strategy of combining activity-based proteome profiling and covalent DEL enrichment (ABPP-CoDEL), which generated selective covalent binders against a variety of target proteins, illustrates the potential use of this methodology in further covalent drug discovery.


Sujet(s)
Protéome , Tyrosine , Protéome/composition chimique , Découverte de médicament/méthodes , Bibliothèques de petites molécules/pharmacologie , Ligands , ADN
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