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1.
Analyst ; 148(24): 6274-6281, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-37969078

RESUMEN

Vanillin (Van) is widely utilized in processed foods and medicines for its appealing scent and multiple therapeutic benefits. However, its overconsumption poses a risk to public health, making its quantification essential for ensuring food and medicine safety and quality. This study introduces a stable and conductive phthalocyanine-based porous organic polymer (NiPc-CC POP), synthesized through a straightforward electrophilic substitution of nickel tetra-amine phthalocyanine (NiTAPc) with cyanuric chloride (CC). Appropriate characterization techniques were employed to determine the morphologies and structures of the synthesized materials. Furthermore, the NiPc-CC POP was applied to devise a sensitive Van detection method. Leveraging the high electrocatalytic activity of NiPc-CC POP toward Van oxidation, a linear response of 0.15-32 µmol L-1 was achieved, along with an exceptional detection limit of 0.10 µmol L-1. The sensor demonstrated high selectivity and stability. Samples of human serum and tablets spiked with Van were analyzed, yielding satisfactory recoveries. Consequently, this work contributes to the advancement of sensitive detection platforms for Van at minimal concentrations.


Asunto(s)
Isoindoles , Polímeros , Humanos , Porosidad
2.
J Peripher Nerv Syst ; 28(4): 629-641, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37749855

RESUMEN

BACKGROUND AND AIMS: Neuronal intranuclear inclusion disease (NIID) is a rare progressive neurodegenerative disorder mainly caused by abnormally expanded GGC repeats within the NOTCH2NLC gene. Most patients with NIID show polyneuropathy. Here, we aim to investigate diagnostic electrophysiological markers of NIID. METHODS: In this retrospective dual-center study, we reviewed 96 patients with NOTCH2NLC-related NIID, 94 patients with genetically confirmed Charcot-Marie-Tooth (CMT) disease, and 62 control participants without history of peripheral neuropathy, who underwent nerve conduction studies between 2018 and 2022. RESULTS: Peripheral nerve symptoms were presented by 53.1% of patients with NIID, whereas 97.9% of them showed peripheral neuropathy according to electrophysiological examinations. Patients with NIID were characterized by slight demyelinating sensorimotor polyneuropathy; some patients also showed mild axonal lesions. Motor nerve conduction velocity (MCV) of the median nerve usually exceeded 35 m/s, and were found to be negatively correlated with the GGC repeat sizes. Regarding the electrophysiological differences between muscle weakness type (n = 27) and non-muscle weakness type (n = 69) of NIID, nerve conduction abnormalities were more severe in the muscle weakness type involving both demyelination and axonal impairment. Notably, specific DWI subcortical lace sign was presented in only 33.3% of muscle weakness type, thus it was difficult to differentiate them from CMT. Combining age of onset, distal motor latency, and compound muscle action potential of the median nerve showed the optimal diagnostic performance to distinguish NIID from major CMT (AUC = 0.989, sensitivity = 92.6%, specificity = 97.4%). INTERPRETATION: Peripheral polyneuropathy is common in NIID. Our study suggest that nerve conduction study is useful to discriminate NIID.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Enfermedades Neurodegenerativas , Humanos , Estudios de Conducción Nerviosa , Estudios Retrospectivos , Enfermedades Neurodegenerativas/diagnóstico , Enfermedad de Charcot-Marie-Tooth/diagnóstico , Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/patología , Debilidad Muscular
3.
Ecotoxicol Environ Saf ; 251: 114526, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36634477

RESUMEN

The extensive use of plastic products and rapid industrialization have created a universal concern about microplastics (MPs). MPs can pose serious environmental risks when combined with heavy metals. However, current research on the combined effects of MPs and hexavalent chromium [Cr(VI)] on plants is insufficient. Herein, a 14-day hydroponic experiment was conducted to investigate the impact of PVC MPs (100 and 200 mg/L) and Cr(VI) (5, 10, and 20 µM) alone and in combination on sweet potato. Results showed that combined Cr(VI) and PVC MPs affected plant growth parameters significantly, but PVC MPs alone did not. The combined application of PVC MPs and Cr(VI) resulted in a decrease in plant height (24-65%), fresh biomass per plant (36-71%), and chlorophyll content (16-34%). Cr(VI) bioaccumulation increased with the increase in its doses, with the highest concentration of Cr(VI) in the leaves (16.45 mg/kg), stems (13.81 mg/kg), and roots (236.65 mg/kg). Cr(VI) and PVC MPs-induced inhibition varied with Cr(VI) and PVC MPs doses. Osmolytes and antioxidants, lipid peroxidation, and H2O2 contents were significantly increased, while antioxidant enzymes except CAT were decreased with increasing Cr(VI) concentration alone and mixed treatments. The presence of PVC MPs promoted Cr(VI) accumulation in sweet potato plants, which clearly showed severe toxic effects on their physio-biochemical characteristics, as indicated by a negative correlation between Cr(VI) concentration and these parameters. PVC MPs alone did not significantly inhibit these parameters. The findings of this study provide valuable implications for the proper management of PVC MPs and Cr(VI) in sweet potato plants.


Asunto(s)
Ipomoea batatas , Microplásticos , Plásticos , Cloruro de Polivinilo/toxicidad , Peróxido de Hidrógeno , Cromo/toxicidad , Antioxidantes
4.
Clin Oral Investig ; 27(2): 671-680, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36374353

RESUMEN

OBJECTIVE: The aim of this study was to compare the difference in length and width of the mandibular retromolar space (RMS) stratified by the different eruption and impaction statuses of the third molars in patients with skeletal Class I malocclusion. MATERIALS AND METHODS: The right mandibular RMS in 186 adult patients categorized according to the different statuses of the third molar was analyzed by using cone-beam computed tomography (CBCT). The shortest distances between the inner lingual cortex of the mandibular body and second molar root were measured parallel to the posterior occlusal line (POL) at depths of 2, 4, 6, 8, and 10 mm (mandibular retromolar space length in root level, RLin2,4,6,8,10) on the axial slices with the cementoenamel junction (CEJ) as the reference level. The width of the RMS and second molar root was measured vertical to the POL at the terminal point of the molar distalization at depths of 2, 4, 6, 8, and 10 mm (width of the mandibular retromolar space, BW2,4,6,8,10/ width of the second molar distal root, TW2,4,6,8,10) from the CEJ. RESULTS: RL in different measurement planes was 2.72 ± 2.22 ~ 3.74 ± 2.26 for Group A, 5.27 ± 1.68 ~ 9.10 ± 2.04 for Group B, 1.94 ± 2.34 ~ 5.71 ± 4.37 for Group C, 1.83 ± 2.95 ~ 5.05 ± 4.24 for Group D, and 5.93 ± 3.97 ~ 10.52 ± 2.16 for Group E. The BW measurement results for A ~ E group were 9.71 ± 1.41 ~ 10.51 ± 1.81, 9.83 ± 1.39 ~ 12.55 ± 2.11, 9.96 ± 1.21 ~ 12.17 ± 1.62, 9.82 ± 1.47 ~ 12.28 ± 2.77, and 10.02 ± 1.20 ~ 12.75 ± 0.82, respectively. There was no significant difference between men and women in any measurements (P > 0.05). Patients with normal third molars erupted and those vertically impacted possessed larger RMS lengths than those in which the third molars were missing, horizontally impacted or mesially impacted (P < 0.05). In each measurement plane, TW was significantly smaller than BW (P < 0.05). CONCLUSIONS: Sex had no effect on the length or width of the mandibular RMS. Different statuses of third molars can also differentially affect the mandibular RMS. The mandibular RMS width is not a limit for mandibular molar distalization. CLINICAL RELEVANCE: When considering the distalization of mandibular molars, more attention should be directed to the lingual cortex of the mandible, and CBCT scans are recommended for patients who require significant mandibular molar distalization. The mandible buccal shelf and retromolar area maybe a safe zone to insert the miniscrew for molar distalization.


Asunto(s)
Maloclusión , Mandíbula , Tercer Molar , Adulto , Femenino , Humanos , Masculino , Tomografía Computarizada de Haz Cónico , Mandíbula/diagnóstico por imagen , Diente Molar/diagnóstico por imagen , Tercer Molar/diagnóstico por imagen , Diente Impactado , Odontometría
5.
J Environ Manage ; 328: 117006, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36521215

RESUMEN

Agro-ecosystem contamination with microplastics (MPs) is of great concern. However, limited research has been conducted on the agricultural soil of tropical regions. This paper investigated MPs in the agro-ecosystem of Hainan Island, China, as well as their relationships with plastic mulching, farming practices, and social and environmental factors. The concentration of MPs in the study area ranged from 2800 to 82500 particles/kg with a mean concentration of 15461.52 particles/kg. MPs with sizes between 20 and 200 µm had the highest abundance of 57.57%, fragment (58.16%) was the most predominant shape, while black (77.76%) was the most abundant MP colour. Polyethylene (PE) (71.04%) and polypropylene (PP) (19.83%) were the main types of polymers. The mean abundance of MPs was significantly positively correlated (p < 0.01) with all sizes, temperature, and shapes except fibre, while weakly positively correlated with the population (p = 0.21), GDP (p = 0.33), and annual precipitation (p = 0.66). In conclusion, plastic mulching contributed to significant contamination of soil MPs in the study area, while environmental and social factors promoted soil MPs fragmentation. The current study results indicate serious contamination with MPs, which poses a concern regarding ecological and environmental safety.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Suelo , Ecosistema , Agricultura , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis
6.
Appl Environ Microbiol ; 88(20): e0107622, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36197104

RESUMEN

The Gram-negative bacterium Cytophaga hutchinsonii digests cellulose through a novel cellulose degradation mechanism. It possesses the lately characterized type IX secretion system (T9SS). We recently discovered that N-glycosylation of the C-terminal domain (CTD) of a hypothetical T9SS substrate protein in the periplasmic space of C. hutchinsonii affects protein secretion and localization. In this study, green fluorescent protein (GFP)-CTDCel9A recombinant protein was found with increased molecular weight in the periplasm of C. hutchinsonii. Site-directed mutagenesis studies on the CTD of cellulase Cel9A demonstrated that asparagine residue 900 in the D-X-N-X-S motif is important for the processing of the recombinant protein. We found that the glycosyltransferase-related protein GtrA (CHU_0012) located in the cytoplasm of C. hutchinsonii is essential for outer membrane localization of the recombinant protein. The deletion of gtrA decreased the abundance of the outer membrane proteins and affected cellulose degradation by C. hutchinsonii. This study provided a link between the glycosylation system and cellulose degradation in C. hutchinsonii. IMPORTANCE N-Glycosylation systems are generally limited to some pathogenic bacteria in prokaryotes. The disruption of the N-glycosylation pathway is related to adherence, invasion, colonization, and other phenotypic characteristics. We recently found that the cellulolytic bacterium Cytophaga hutchinsonii also has an N-glycosylation system. The cellulose degradation mechanism of C. hutchinsonii is novel and mysterious; cellulases and other proteins on the cell surface are involved in utilizing cellulose. In this study, we identified an asparagine residue in the C-terminal domain of cellulase Cel9A that is necessary for the processing of the T9SS cargo protein. Moreover, the glycosyltransferase-related protein GtrA is essential for the localization of the GFP-CTDCel9A recombinant protein. Deletion of gtrA affected cellulose degradation and the abundance of outer membrane proteins. This study enriched the understanding of the N-glycosylation system in C. hutchinsonii and provided a link between N-glycosylation and cellulose degradation, which also expanded the role of the N-glycosylation system in bacteria.


Asunto(s)
Celulasa , Celulasa/genética , Celulasa/metabolismo , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Asparagina/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Cytophaga/genética , Cytophaga/metabolismo , Celulosa/metabolismo , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Biomacromolecules ; 22(8): 3342-3356, 2021 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-34212713

RESUMEN

PGA and P(GA-co-LA) fibers applied as surgical sutures strongly depend on their microstructure. The structural evolution in both the relaxed and tensioned states during heat-setting after hot stretching, which included heating and postannealing, was investigated using in situ WAXD/SAXS and DSC techniques. We found that the fibers of both PGA and P(GA-co-LA) with 8% LA content under the relaxed state were more advantageous than the fibers under the tensioned state indicated by the larger crystallite sizes and unit cell parameters and the higher crystallinity. The mechanical properties of the samples increased after heat-setting. Heat-setting at 120 °C was more suitable for promoting the fiber properties, which can be ascribed to crystal formation and perfection. During the heating, the thermal expansion increased the unit cell parameters and the long period of PGA linearly, whereas the unit cell parameters of P(GA-co-LA) had an obvious turning point at 60-80 °C, and the long period showed a sudden decline in the temperature range of 60-80 °C, which was mainly the result of the discharge of LA units. The unit cell parameters and the long period of both PGA and P(GA-co-LA) decreased during the isotherm process due to crystal perfection. However, the P(GA-co-LA) decrease was more prominent than PGA because of the inclusion of LA monomers in the crystal structure of GAs.


Asunto(s)
Calor , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Dispersión del Ángulo Pequeño , Difracción de Rayos X
8.
Macromol Rapid Commun ; 42(14): e2100174, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33955093

RESUMEN

Nonconventional luminescence polymers without any aromatic structures have attracted great interest from researchers due to their special structure and excellent biocompatibility. However, these materials mostly emit in the blue or green region, in which preparation of materials with long-wavelength (especially near-infrared) emission is still a great challenge. In this work, it is found that 2-(dimethyl amino) ethyl methacrylate (DMA) and itaconic anhydride (ITA) undergo a ring-opening reaction at room temperature, and subsequently generate zwitterionic compound (IDMA). Based on the clustering-triggered emission (CTE) mechanism, ionic bond can effectively promote the isolated electron-rich chromophores to form new emissive clusters with extended electron delocalization. Herein, two oligomers (P1 and P2) with different fluorescence emissions by controlling the concentration of zwitterionic monomers before polymerization are synthesized. It is worth noting that the maximum emission wavelength of P2 at high concentration is up to 712 nm, which is very rare in previous reports. In addition, the resulting oligomer (P2) shows typical aggregation-enhanced emission (AEE), excitation-dependent fluorescence, temperature-sensitive emission, and solvatochromism. The cytotoxicity assay demonstrates that P2 was low toxic to Huh7 and LM3 cells, and suitable for cell imaging. This research provides the possibility for rational molecular design and the feasibility of luminescence regulation.


Asunto(s)
Luminiscencia , Polímeros , Fluorescencia , Polimerizacion , Temperatura
9.
J Environ Manage ; 266: 110577, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32310119

RESUMEN

Recycling of plastics from e-waste can conserve resources, however, aging during the use of plastic products can cause the migration of heavy metals in additives. This study presents a methodology for evaluating the risks of heavy metals in waste plastic secondary products during long term use associated with heavy metal migration. The study processes were investigated by: (1) recycling waste plastics and producing secondary products; (2) thermal aging of secondary products; and (3) toxic leaching used to quantitatively analyse the dissolution of heavy metals. Combined with the changes in mechanical properties and microstructure, the effect of aging on the migration of heavy metals was observed. The results showed that the polymer appeared to delaminate, the adhesion of waste plastics to additives decreased, and the mechanical properties clearly decreased after the thermal aging experiment. Leaching experiments showed that the leached concentrations of Ni, Cu, Zn, Pb, and Sb in the three types waste plastic products increased over time. After 8 d of aging, the leached concentrations of Ni, Sb, and Pb exceeded the third, fourth, and third class of the groundwater quality standard, respectively. Specifically, the concentrations of Sb were 141, 289, and 21.1 times higher than the maximum permissible level. Therefore, management hierarchy and safe environmental recycling methods should be developed to reduce the risk of heavy metals in waste plastic secondary products.


Asunto(s)
Residuos Electrónicos , Metales Pesados , Contaminantes del Suelo , Plásticos , Reciclaje
10.
Yao Xue Xue Bao ; 49(9): 1331-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25518335

RESUMEN

Lysostaphin is highly effective on eliminating methicillin resistant Staphylococcus aureus (MRSA). In order to achieve controlled release of lysostaphin, a biocompatible drug carrier is needed. Hydroxyapatite/chitosan (HA/CS) composites were chosen to carry lysostaphin and sample composites with different weight ratios of HA to CS, including 80/20, 70/30, 60/40, and 40/60, were prepared. Multiple analyses were performed to determine the structural and physicochemical properties of the composites, including scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. We immersed HA/CS composites loaded with 1 wt% lysostaphin to test in vitro release activity and cultured MC3T3-E1 cells to carry out biocompatibility test. The result of the release behavior of the composites revealed that the controlled release of lysostaphin from 60/40 HA/CS composites was the highest release rate of (87.4 ± 2.8)%, which lasted for 120 hours. In biocompatibility testing, MC3T3-E1 cells were able to proliferate on the surface of these composites, and the extract liquid from the composites could increase the growth of the cells. These results demonstrate the controlled release of lysostaphin from HA/CS composites and their biocompatibility, suggesting the potential application of these composites to bone injury and infection applications.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Durapatita/química , Lisostafina/farmacología , Células 3T3 , Animales , Materiales Biocompatibles , Preparaciones de Acción Retardada , Ensayo de Materiales , Staphylococcus aureus Resistente a Meticilina , Ratones , Microscopía Electrónica de Rastreo , Difracción de Rayos X
11.
Anal Methods ; 16(7): 1012-1020, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38304962

RESUMEN

Isoniazid is a first-line drug used to treat tuberculosis. However, its excessive use can lead to serious adverse effects. Thus, strict monitoring of the isoniazid levels in medications and human systems is required. In this study, a new polymer (AlPc-TB POP) containing a metal phthalocyanine and Tröger's base was synthesized and explored as an electrocatalyst for the oxidation of isoniazid. The results indicated that the polymer is an excellent electron-transfer medium for isoniazid oxidation. The AlPc-TB POP-based sensor quantified isoniazid in the linear range of 0.1-130 µM, with a detection limit of 0.0185 µM. The response of the developed sensor to isoniazid was reproducible and stable. Furthermore, this method can accurately determine isoniazid levels by ignoring the influence of common interfering species in tablets and biological samples. This study contributes to the development of nitrogen-rich porous organic polymers and offers a novel strategy for addressing challenges in disease therapeutic efficacy and public safety monitoring.


Asunto(s)
Indoles , Isoindoles , Isoniazida , Compuestos Organometálicos , Polímeros , Humanos , Aluminio , Antituberculosos/uso terapéutico
12.
Front Neurol ; 15: 1407152, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938777

RESUMEN

Background and objectives: Upwards of 50% of acute ischemic stroke (AIS) survivors endure varying degrees of disability, with a recurrence rate of 17.7%. Thus, the prediction of outcomes in AIS may be useful for treatment decisions. This study aimed to determine the applicability of a machine learning approach for forecasting early outcomes in AIS patients. Methods: A total of 659 patients with new-onset AIS admitted to the Department of Neurology of both the First and Second Affiliated Hospitals of Bengbu Medical University from January 2020 to October 2022 included in the study. The patient' demographic information, medical history, Trial of Org 10,172 in Acute Stroke Treatment (TOAST), National Institute of Health Stroke Scale (NIHSS) and laboratory indicators at 24 h of admission data were collected. The Modified Rankine Scale (mRS) was used to assess the 3-mouth outcome of participants' prognosis. We constructed nine machine learning models based on 18 parameters and compared their accuracies for outcome variables. Results: Feature selection through the Least Absolute Shrinkage and Selection Operator cross-validation (Lasso CV) method identified the most critical predictors for early prognosis in AIS patients as white blood cell (WBC), homocysteine (HCY), D-Dimer, baseline NIHSS, fibrinogen degradation product (FDP), and glucose (GLU). Among the nine machine learning models evaluated, the Random Forest model exhibited superior performance in the test set, achieving an Area Under the Curve (AUC) of 0.852, an accuracy rate of 0.818, a sensitivity of 0.654, a specificity of 0.945, and a recall rate of 0.900. Conclusion: These findings indicate that RF models utilizing general clinical and laboratory data from the initial 24 h of admission can effectively predict the early prognosis of AIS patients.

13.
Bioresour Technol ; 395: 130325, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228219

RESUMEN

Herein, three enzymes (cellulase, ß-glucosidase, and pectinase) with synergistic effects were co-immobilized on the Eudragit L-100, and the recovery of co-immobilized enzymes from solid substrates were achieved through the reversible and soluble property of the carrier. The optimization of enzyme ratio overcomed the problem of inappropriate enzyme activity ratio caused by different immobilization efficiencies among enzymes during the preparation process of co-immobilized enzymes. The co-immobilized enzymes were utilized to catalytically hydrolyze cellulose from corn straw into glucose, achieving a cellulose conversion rate of 74.45% under conditions optimized for their enzymatic characteristics and hydrolytic reaction conditions. As a result of the reversibility and solubility of the carrier, the co-immobilized enzymes were recovered from the solid substrate after five cycles, retaining 54.67% of the enzyme activity. The aim of this study is to investigate the potential of co-immobilizing multiple enzymes onto the Eudragit L-100 carrier for the synergistic degradation of straw cellulose.


Asunto(s)
Celulasa , Celulosa , Celulosa/metabolismo , Zea mays/metabolismo , Enzimas Inmovilizadas/metabolismo , Ácidos Polimetacrílicos , Celulasa/metabolismo , Hidrólisis
14.
Int J Biol Macromol ; 260(Pt 2): 129538, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38246467

RESUMEN

Enzymatic degradation has been proposed as a suitable solution for addressing PET pollution, but approximately 10 % of PET is left as nonbiodegradable. Microbes can completely degrade PET at the gram level per year. Based on the complementary benefits of microbes and enzymes, a microbe-enzyme system was created to completely degrade PET. Here, a thermophilic microbe-enzyme (TME) system composed of Bacillus thermoamylovorans JQ3 and leaf-branch compost cutinase variant (ICCG) was used to demonstrate the synergistic degradation of PET, enabling 100 % degradation of PET waste at a high PET loading level (360 g/L). Six endogenous PET hydrolases of strain JQ3 were discovered by employing an ester bond hydrolysis function-first genome mining (EGM) strategy and first successfully expressed in E. coli. These hydrolases could release TPA as the final product from PET and preferentially degraded BHET instead of MHET. Of these, carboxylesterase 39_5 and ICCG could degrade PET in a synergistic manner to generate 50 µM of TPA, which was greater than the sum of the individual treatments. Finally, the degradation pathway of the TME system was speculated to include biofilm formation, PET degradation and utilization. The successful implementation of this study rendered a scale-up degradation feasible of PET at a lower cost.


Asunto(s)
Escherichia coli , Tereftalatos Polietilenos , Escherichia coli/metabolismo , Tereftalatos Polietilenos/química , Hidrolasas/química , Hidrólisis
15.
Adv Mater ; 36(16): e2311474, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38194906

RESUMEN

During liver fibrogenesis, the reciprocal crosstalk among capillarized liver sinusoidal endothelial cells (LSECs), activated hepatic stellate cells (HSCs), and dysfunctional hepatocytes constructs a self-amplifying vicious cycle, greatly exacerbating the disease condition and weakening therapeutic effect. Limited by the malignant cellular interactions, the previous single-cell centric treatment approaches show unsatisfactory efficacy and fail to meet clinical demand. Herein, a vicious cycle-breaking strategy is proposed to target and repair pathological cells separately to terminate the malignant progression of liver fibrosis. Chondroitin sulfate-modified and vismodegib-loaded nanoparticles (CS-NPs/VDG) are designed to efficiently normalize the fenestrae phenotype of LSECs and restore HSCs to quiescent state by inhibiting Hedgehog signaling pathway. In addition, glycyrrhetinic acid-modified and silybin-loaded nanoparticles (GA-NPs/SIB) are prepared to restore hepatocytes function by relieving oxidative stress. The results show successful interruption of vicious cycle as well as distinct fibrosis resolution in two animal models through multiregulation of the pathological cells. This work not only highlights the significance of modulating cellular crosstalk but also provides a promising avenue for developing antifibrotic regimens.


Asunto(s)
Células Endoteliales , Liposomas , Nanopartículas , Animales , Células Endoteliales/metabolismo , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/uso terapéutico , Cirrosis Hepática , Hígado/metabolismo
16.
J Hazard Mater ; 466: 133540, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38241834

RESUMEN

The effect of microplastics (MPs) on the allocation of rice photosynthetic carbon (C) in paddy systems and its utilization by soil microorganisms remain unclear. In this study, 13C-CO2 pulse labeling was used to quantify the input and allocation of photosynthetic C in a rice-soil system under MPs amendment. Rice was pulse-labeled at tillering growth stage under 0.01% and 1% w/w polyethylene (PE) and polyvinyl chloride (PVC) MP amendments. Plants and soils were sampled 24 h after pulse labeling. Photosynthesized C in roots in MP treatments was 30-54% lower than that in no-MP treatments. The 13C in soil organic C (SOC) in PVC-MP-amended bulk soil was 4.3-4.7 times higher than that in no-MP treatments. PVC and high-dose PE increased the photosynthetic C in microbial biomass C in the rhizosphere soil. MPs altered the allocation of photosynthetic C to microbial phospholipid fatty acid (PLFA) groups. High-dose PVC increased the 13C gram-positive PLFAs. Low-dose PE and high-dose PVC enhanced 13C in fungal PLFAs in bulk soil (including arbuscular mycorrhizal fungi (AMF) and Zygomycota) by 175% and 197%, respectively. The results highlight that MPs alter plant C input and microbial utilization of rhizodeposits, thereby affecting the C cycle in paddy ecosystems.


Asunto(s)
Oryza , Suelo , Microplásticos , Plásticos , Ecosistema , Microbiología del Suelo , Carbono , Polietilenos
17.
J Mater Sci Mater Med ; 24(5): 1229-37, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23430335

RESUMEN

It is well known that some microorganisms affect the corrosion of dental metal. Oral bacteria such as Actinomyces naeslundii may alter the corrosion behavior and stability of titanium. In this study, the corrosion behavior of titanium was studied in a nutrient-rich medium both in the presence and the absence of A. naeslundii using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and electrochemical impedance spectroscopy (EIS). A. naeslundii was able to colonize the surface of titanium and then form a dense biofilm. The SEM images revealed the occurrence of micropitting corrosion on the metal surface after removal of the biofilm. The electrochemical corrosion results from EIS showed a significant decrease in the corrosion resistant (R(p)) value after immersing the metal in A. naeslundii culture for 3 days. Correspondingly, XPS revealed a reduction in the relative levels of titanium and oxygen and an obvious reduction of dominant titanium dioxide (TiO2) in the surface oxides after immersion of the metal in A. naeslundii culture. These results suggest that the metabolites produced by A. naeslundii can weaken the integrity and stability of the protective TiO2 in the surface oxides, which in turn decreases the corrosion resistance of titanium, resulting in increased corrosion of titanium immersed in A. naeslundii solution as a function of time.


Asunto(s)
Actinomyces/fisiología , Titanio/química , Biopelículas/crecimiento & desarrollo , Corrosión , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Espectroscopía de Fotoelectrones , Propiedades de Superficie
18.
Environ Sci Pollut Res Int ; 30(32): 78607-78618, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37273044

RESUMEN

Evidence suggests a possible association between ambient air pollutants and oral diseases. Nevertheless, information regarding the relationship between air pollutants and pulpitis is scarce and inconclusive. In view of this, the present study aimed to investigate the relationship between short-term exposure to air pollution and outpatient visits for pulpitis. Daily data on outpatient visits for pulpitis, air pollutants, and meteorological data in Hefei, China, was collected from January 1, 2015 to December 31, 2021. The association between exposure to air pollutants and pulpitis outpatient visits was evaluated using distributed lag non-linear model (DLNM) and a generalized linear model (GLM). Furthermore, stratified analyses were performed by gender, age and season. A total of 93,324 records of outpatient visits for pulpitis were included in this study. The results showed that exposure to NO2, PM2.5, and CO were positively correlated with an increased risk of pulpitis outpatient visits. Each 10 µg/m3 increase in NO2 and PM2.5 concentration, at lag 0-2 day, was associated with a 2.4% (relative risk (RR) = 1.024, 95% confidence interval (CI): 1.014-1.035) and 0.5% (RR = 1.005, 95% CI: 1.000-1.010) increase in pulpitis outpatient visits, respectively. With a 1 mg/m3 increase in CO concentration, the risk of pulpitis outpatient visits increased by 9.1% (RR = 1.091, 95% CI: 1.031-1.154, lag 0-1 day). Intriguingly, exposure to O3 was associated with a decreased risk of pulpitis outpatient visits (RR = 0.990, 95% CI: 0.984-0.995, lag 0-5 day). Subgroup analysis revealed that in the warm season, exposure to PM2.5, O3, and CO was related with a significantly higher outpatient risk of pulpitis than in the cold season. Additionally, the influence of PM2.5 and CO exposure at age < 65 years was significantly stronger than at age ≥ 65 years. In conclusion, exposure to ambient NO2, PM2.5, and CO is associated with an increase in pulpitis outpatient visits in Hefei, China. Conversely, exposure to O3 reduces the risk of outpatient visits for pulpitis. Age and season are effect modifiers of these associations.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Pulpitis , Humanos , Anciano , Pacientes Ambulatorios , Dióxido de Nitrógeno/análisis , Pulpitis/inducido químicamente , Factores de Tiempo , Contaminación del Aire/análisis , Contaminantes Atmosféricos/análisis , China/epidemiología , Material Particulado/análisis
19.
Comb Chem High Throughput Screen ; 26(6): 1180-1185, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35984022

RESUMEN

BACKGROUND: This study aimed to determine the features and differentiation of Giant Cell Reparative Granuloma (GCRG) and Giant Cell Tumor (GCT) of the head on CT and MRI. METHODS: This retrospective study included six patients with histopathology-confirmed head GCRG and 5 patients with histopathology-confirmed head GCT. All images were independently reviewed by two radiologists. The growth pattern, bone changes, MRI signal intensity, enhancement patterns and other image features were recorded. All patients received CT scans and MR images. RESULTS: All the lesions were located centrally in the bone. Osteolytic bone destruction and expansive growth patterns were observed on CT images. Four of six cases broke the cortical bone with residual cortical bone, and the last two showed a thin cortex in GCRG. Five cases broke the cortical bone with residual cortical bone in GCT. There were enhancing septations in GCT lesions on contrast- enhanced T1-Weighted Images (T1WI) while enhancing septations were not present in GCRG cases. The size of GCT lesions was larger than that of GRCG. GCRG and GCT showed iso-low signals on T1WI and iso-high signals on T2-Weighted Images (T2WI). There was a case with cystic or necrotic lesions in each of the two types of lesions. Osteolytic bone destruction and expansive growth patterns were observed in GCTs and GCRGs. CONCLUSION: The size of the GRCG lesion was smaller than that of the GCT. The presence of enhancing septations and the size of the lesion may distinguish GCTs from GCRG.


Asunto(s)
Neoplasias Óseas , Tumores de Células Gigantes , Granuloma de Células Gigantes , Humanos , Estudios Retrospectivos , Neoplasias Óseas/diagnóstico por imagen , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Granuloma de Células Gigantes/diagnóstico por imagen , Granuloma de Células Gigantes/metabolismo , Células Gigantes/metabolismo , Células Gigantes/patología
20.
Nanotechnology ; 23(38): 385705, 2012 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-22948006

RESUMEN

We present a surface-enhanced Raman scattering (SERS) substrate featured by large-scale homogeneously distributed Ag nanoparticles (Ag-NPs) with sub-10 nm gaps assembled on a two-layered honeycomb-like TiO(2) film. The two-layered honeycomb-like TiO(2) film was achieved by a two-step anodization of pure Ti foil, with its upper layer consisting of hexagonally arranged shallow nano-bowls of 160 nm in diameter, and the lower layer consisting of arrays of about fifty vertically aligned sub-20 nm diameter nanopores. The shallow nano-bowls in the upper layer divide the whole TiO(2) film into regularly arranged arrays of uniform hexagonal nano-cells, leading to a similar distribution pattern for the ion-sputtered Ag-NPs in each nano-cell. The lower layer with sub-20 nm diameter nanopores prevents the aggregation of the sputtered Ag-NPs, so that the Ag-NPs can get much closer with gaps in the sub-10 nm range. Therefore, large-scale high-density and quasi-ordered sub-10 nm gaps between the adjacent Ag-NPs were achieved, which ensures homogeneously distributed 'hot spots' over a large area for the SERS effect. Moreover, the honeycomb-like structure can also facilitate the capture of target analyte molecules. As expected, the SERS substrate exhibits an excellent SERS effect with high sensitivity and reproducibility. As an example, the SERS substrate was utilized to detect polychlorinated biphenyls (PCBs, a kind of persistent organic pollutants as global environmental hazard) such as 3,3',4,4'-pentachlorobiphenyl (PCB-77) with concentrations down to 10(-9) M. Therefore the large-scale Ag-NPs with sub-10 nm gaps assembled on the two-layered honeycomb-like TiO (2) film have potentials in SERS-based rapid trace detection of PCBs.


Asunto(s)
Membranas Artificiales , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Plata/química , Espectrometría Raman/métodos , Titanio/química , Luz , Ensayo de Materiales , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad
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