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1.
Langmuir ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958522

RESUMO

Amino acids make up a promising family of molecules capable of direct air capture (DAC) of CO2 from the atmosphere. Under alkaline conditions, CO2 reacts with the anionic form of an amino acid to produce carbamates and deactivated zwitterionic amino acids. The presence of the various species of amino acids and reactive intermediates can have a significant effect on DAC chemistry, the role of which is poorly understood. In this study, all-atom molecular dynamics (MD) based computational simulations and vibrational sum frequency generation (vSFG) spectroscopy studies were conducted to understand the role of competitive interactions at the air-aqueous interface in the context of DAC. We find that the presence of potassium bicarbonate ions, in combination with the anionic and zwitterionic forms of amino acids, induces concentration and charge gradients at the interface, generating a layered molecular arrangement that changes under pre- and post-DAC conditions. In parallel, an enhancement in the surface activity of both anionic and zwitterionic forms of amino acids is observed, which is attributed to enhanced interfacial stability and favorable intermolecular interactions between the adsorbed amino acids in their anionic and zwitterionic forms. The collective influence of these competitive interactions, along with the resulting interfacial heterogeneity, may in turn affect subsequent capture reactions and associated rates. These effects underscore the need to consider dynamic changes in interfacial chemical makeup to enhance DAC efficiency and to develop successful negative emission and storage technologies.

2.
Harmful Algae ; 135: 102630, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38830708

RESUMO

Ships' ballast water and sediments have long been linked to the global transport and expansion of invasive species and thus have become a hot research topic and administrative challenge in the past decades. The relevant concerns, however, have been mainly about the ocean-to-ocean invasion and sampling practices have been almost exclusively conducted onboard. We examined and compared the dinoflagellate cysts assemblages in 49 sediment samples collected from ballast tanks of international and domestic routes ships, washing basins associated with a ship-repair yard, Jiangyin Port (PS), and the nearby area of Yangtze River (YR) during 2017-2018. A total of 43 dinoflagellates were fully identified to species level by metabarcoding, single-cyst PCR-based sequencing, cyst germination and phylogenetic analyses, including 12 species never reported from waters of China, 14 HABs-causing, 9 toxic, and 10 not strictly marine species. Our metabarcoding and single-cyst sequencing also detected many OTUs and cysts of dinoflagellates that could not be fully identified, indicating ballast tank sediments being a risky repository of currently unrecognizable invasive species. Particularly important, 10 brackish and fresh water species of dinoflagellate cysts (such as Tyrannodinium edax) were detected from the transoceanic ships, indicating these species may function as alien species potentially invading the inland rivers and adjacent lakes if these ships conduct deballast and other practices in fresh waterbodies. Significantly higher numbers of reads and OTUs of dinoflagellates in the ballast tanks and washing basins than that in PS and YR indicate a risk of releasing cysts by ships and the associated ship-repair yards to the surrounding waters. Phylogenetic analyses revealed high intra-species genetic diversity for multiple cyst species from different ballast tanks. Our work provides novel insights into the risk of bio-invasion to fresh waters conveyed in ship's ballast tank sediments and washing basins of shipyards.


Assuntos
Dinoflagellida , Água Doce , Espécies Introduzidas , Filogenia , Navios , Dinoflagellida/fisiologia , Dinoflagellida/genética , Dinoflagellida/classificação , Água Doce/parasitologia , China , Ecossistema , Sedimentos Geológicos , Proliferação Nociva de Algas
3.
J Colloid Interface Sci ; 669: 552-560, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38729003

RESUMO

HYPOTHESIS: Understanding the rules that control the assembly of nanostructured soft materials at interfaces is central to many applications. We hypothesize that electrolytes can be used to alter the hydration shell of amphiphilic oligomers at the air-aqueous interface of Langmuir films, thereby providing a means to control the formation of emergent nanostructures. EXPERIMENTS: Three representative salts - (NaF, NaCl, NaSCN) were studied for mediating the self-assembly of oligodimethylsiloxane methylimidazolium (ODMS-MIM+) amphiphiles in Langmuir films. The effects of the different salts on the nanostructure assembly of these films were probed using vibrational sum frequency generation (SFG) spectroscopy and Langmuir trough techniques. Experimental data were supported by atomistic molecular dynamic simulations. FINDINGS: Langmuir trough surface pressure - area isotherms suggested a surprising effect on oligomer assembly, whereby the presence of anions affects the stability of the interfacial layer irrespective of their surface propensities. In contrast, SFG results implied a strong anion effect that parallels the surface activity of anions. These seemingly contradictory trends are explained by anion driven tail dehydration resulting in increasingly heterogeneous systems with entangled ODMS tails and appreciable anion penetration into the complex interfacial layer comprised of headgroups, tails, and interfacial water molecules. These findings provide physical and chemical insight for tuning a wide range of interfacial assemblies.

4.
Front Bioeng Biotechnol ; 12: 1337808, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681963

RESUMO

Introduction: Magnetic Resonance Imaging (MRI) is essential in diagnosing cervical spondylosis, providing detailed visualization of osseous and soft tissue structures in the cervical spine. However, manual measurements hinder the assessment of cervical spine sagittal balance, leading to time-consuming and error-prone processes. This study presents the Pyramid DBSCAN Simple Linear Iterative Cluster (PDB-SLIC), an automated segmentation algorithm for vertebral bodies in T2-weighted MR images, aiming to streamline sagittal balance assessment for spinal surgeons. Method: PDB-SLIC combines the SLIC superpixel segmentation algorithm with DBSCAN clustering and underwent rigorous testing using an extensive dataset of T2-weighted mid-sagittal MR images from 4,258 patients across ten hospitals in China. The efficacy of PDB-SLIC was compared against other algorithms and networks in terms of superpixel segmentation quality and vertebral body segmentation accuracy. Validation included a comparative analysis of manual and automated measurements of cervical sagittal parameters and scrutiny of PDB-SLIC's measurement stability across diverse hospital settings and MR scanning machines. Result: PDB-SLIC outperforms other algorithms in vertebral body segmentation quality, with high accuracy, recall, and Jaccard index. Minimal error deviation was observed compared to manual measurements, with correlation coefficients exceeding 95%. PDB-SLIC demonstrated commendable performance in processing cervical spine T2-weighted MR images from various hospital settings, MRI machines, and patient demographics. Discussion: The PDB-SLIC algorithm emerges as an accurate, objective, and efficient tool for evaluating cervical spine sagittal balance, providing valuable assistance to spinal surgeons in preoperative assessment, surgical strategy formulation, and prognostic inference. Additionally, it facilitates comprehensive measurement of sagittal balance parameters across diverse patient cohorts, contributing to the establishment of normative standards for cervical spine MR imaging.

5.
Chempluschem ; : e202300713, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456801

RESUMO

The intensive energy demands associated with solvent regeneration and CO2 release in current direct air capture (DAC) technologies makes their deployment at the massive scales (GtCO2/year) required to positively impact the climate economically unfeasible. This challenge underscores the critical need to develop new DAC processes with significantly reduced energy costs. Recently, we developed a new approach to photochemically drive efficient release of CO2 through an intermolecular proton transfer reaction by exploiting the unique properties of an indazole metastable-state photoacid (mPAH), opening a new avenue towards energy efficient on-demand CO2 release and solvent regeneration using abundant solar energy instead of heat. In this Concept Article, we will describe the principle of our photochemically-driven CO2 release approach for solvent-based DAC systems, discuss the essential prerequisites and conditions to realize this cyclable CO2 release chemistry under ambient conditions. We outline the key findings of our approach, discuss the latest developments from other research laboratories, detail approaches used to monitor DAC systems in situ, and highlight experimental procedures for validating its feasibility. We conclude with a summary and outlook into the immediate challenges that must be addressed in order to fully exploit this novel photochemically-driven approach to DAC solvent regeneration.

6.
Int J Mol Sci ; 25(3)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38339002

RESUMO

The ever-increasing applications of metabarcoding analyses for environmental samples demand a well-designed assessment of the stability of DNA and RNA contained in cells that are deposited or buried in marine sediments. We thus conducted a qPCR quantification of the DNA and RNA in the vegetative cells of three microalgae entrapped in facsimile marine sediments and found that >90% of DNA and up to 99% of RNA for all microalgal species were degraded within 60 days at 4 °C. A further examination of the potential interference of the relic DNA of the vegetative cells with resting cyst detection in sediments was performed via a metabarcoding analysis in artificial marine sediments spiked with the vegetative cells of two Kareniaceae dinoflagellates and the resting cysts of another three dinoflagellates. The results demonstrated a dramatic decrease in the relative abundances of the two Kareniaceae dinoflagellates in 120 days, while those of the three resting cysts increased dramatically. Together, our results suggest that a positive detection of microalgae via metabarcoding analysis in DNA or RNA extracted from marine sediments strongly indicates the presence of intact or viable cysts or spores due to the rapid decay of relic DNA/RNA. This study provides a solid basis for the data interpretation of metabarcoding surveys, particularly in resting cyst detection.


Assuntos
Dinoflagellida , Microalgas , Microalgas/genética , DNA , Dinoflagellida/genética , Código de Barras de DNA Taxonômico/métodos , RNA/genética , Estabilidade de RNA , Sedimentos Geológicos
7.
ACS Appl Mater Interfaces ; 16(9): 12052-12061, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38411063

RESUMO

Interfaces are considered a major bottleneck in the capture of CO2 from air. Efforts to design surfaces to enhance CO2 capture probabilities are challenging due to the remarkably poor understanding of chemistry and self-assembly taking place at these interfaces. Here, we leverage surface-specific vibrational spectroscopy, Langmuir trough techniques, and simulations to mechanistically elucidate how cationic oligomers can drive surface localization of amino acids (AAs) that serve as CO2 capture agents speeding up the apparent rate of absorption. We demonstrate how tuning these interfaces provides a means to facilitate CO2 capture chemistry to occur at the interface, while lowering surface tension and improving transport/reaction probabilities. We show that in the presence of interfacial AA-rich aggregates, one can improve capture probabilities vs that of a bare interface, which holds promise in addressing climate change through the removal of CO2 via tailored interfaces and associated chemistries.

8.
Phys Chem Chem Phys ; 26(5): 4062-4070, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38224171

RESUMO

Direct access to trans-cis photoisomerization in a metastable state photoacid (mPAH) remains challenging owing to the presence of competing excited-state relaxation pathways and multiple transient isomers with overlapping spectra. Here, we reveal the photoisomerization dynamics in an indazole mPAH using time-resolved fluorescence (TRF) spectroscopy by exploiting a unique property of this mPAH having fluorescence only from the trans isomer. The combination of these experimental results with time-dependent density function theory (TDDFT) calculations enables us to gain mechanistic insight into this key dynamical process.

9.
Neurol Clin Pract ; 14(1): e200232, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38213398

RESUMO

Background and Objectives: Most acute symptomatic seizure (ASyS) patients stay on antiseizure medications (ASM) long-term, despite low epilepsy development risk. The Post-Acute Symptomatic Seizure (PASS) clinic is a transition of care model for ASyS patients who individualize ASM management with the goal of a safe deprescription. We evaluated patients discharged on ASMs after a witnessed or suspected ASyS to analyze their PASS clinic visit attendance and its predictors. Methods: A single-center, retrospective cohort study of adults without epilepsy who were discharged from January 1, 2019, to September 30, 2019, on first-time ASMs due to witnessed or suspected ASyS (PASS clinic-eligible). We fit a cause-specific Cox proportional hazards model to analyze factors associated with PASS clinic attendance, which depends on survival in this patient population that has a high early postdischarge mortality (a competing risk). We checked for multicollinearity and the assumption of proportional hazards. Results: Among 307 PASS clinic-eligible patients, 95 (30.9%) attended the clinic and 136 (44.3%) died during a median follow-up of 14 months (interquartile range = 2-34). ASyS occurred in 60.2% (convulsive 47%; electrographic 26.7%) of patients. ASMs were continued in the absence of ASyS or epileptiform abnormalities (EAs) in 27% of patients. Multivariable analysis revealed that the presence of EAs (HR = 1.69, 95% CI 1.10-2.59), PASS clinic appointments provided before discharge (HR = 3.39, 95% CI 2.15-5.33), and less frequently noted ASyS etiologies such as autoimmune encephalitis (HR = 2.03, 95% CI 1.07-3.86) were associated with an increased clinic attendance rate. Medicare/Medicaid insurance (HR = 0.43, 95% CI 0.24-0.78, p = 0.005) and the presence of progressive brain injury (i.e., tumors; HR = 0.55, 95% CI 0.32-0.95, p = 0.032) were associated with reduced rate of PASS clinic attendance. Discussion: Our real-world data highlight the need for appropriate postdischarge follow-up of ASyS patients, which can be fulfilled by the PASS clinic model. Modest PASS clinic attendance can be significantly improved by adhering to a structured discharge planning process whereby appointments are provided before discharge. Future research comparing patient outcomes, specifically safe ASM discontinuation in a PASS clinic model to routine clinical care, is needed.

10.
Angew Chem Int Ed Engl ; 62(29): e202304957, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37198131

RESUMO

One of the grand challenges underlying current direct air capture (DAC) technologies relates to the intensive energy cost for sorbent regeneration and CO2 release, making the massive scale (GtCO2 /year) deployment required to have a positive impact on climate change economically unfeasible. This challenge underscores the critical need to develop new DAC processes with substantially reduced regeneration energies. Here, we report a photochemically-driven approach for CO2 release by exploiting the unique properties of an indazole metastable-state photoacid (mPAH). Our measurements on simulated and amino acid-based DAC systems revealed the potential of mPAH to be used for CO2 release cycles by regulating pH changes and associated isomers driven by light. Upon irradiating with moderate intensity light, a ≈55 % and ≈68 % to ≈78 % conversion of total inorganic carbon to CO2 was found for the simulated and amino acid-based DAC systems, respectively. Our results confirm the feasibility of on-demand CO2 release under ambient conditions using light instead of heat, thereby providing an energy efficient pathway for the regeneration of DAC sorbents.

11.
J Phys Chem B ; 127(21): 4886-4895, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37216432

RESUMO

Liquid/liquid (L/L) interfaces play a key, yet poorly understood, role in a range of complex chemical phenomena where time-evolving interfacial structures and transient supramolecular assemblies act as gatekeepers to function. Here, we employ surface-specific vibrational sum frequency generation combined with neutron and X-ray scattering methods to track the transport of dioctyl phosphoric acid (DOP) and di-(2-ethylhexyl) phosphoric acid (DEHPA) ligands used in solvent extraction at buried oil/aqueous interfaces away from equilibrium. Our results show evidence for a dynamic interfacial restructuring at low ligand concentrations in contrast to expectation. These time-varying interfaces arise from the transport of sparingly soluble interfacial ligands into the neighboring aqueous phase. These results support a proposed "antagonistic" role of ligand complexation in the aqueous phase that could serve as a holdback mechanism in kinetic liquid extractions. These findings provide new insights into interfacially controlled chemical transport at L/L interfaces and how these interfaces vary chemically, structurally, and temporally in a concentration-dependent manner and present potential avenues to design selective kinetic separations.

12.
ACS Appl Mater Interfaces ; 15(15): 19634-19645, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-36944180

RESUMO

As fossil fuels remain a major source of energy throughout the world, developing efficient negative emission technologies, such as direct air capture (DAC), which remove carbon dioxide (CO2) from the air, becomes critical for mitigating climate change. Although all DAC processes involve CO2 transport from air into a sorbent/solvent, through an air-solid or air-liquid interface, the fundamental roles the interfaces play in DAC remain poorly understood. Herein, we study the interfacial behavior of amino acid (AA) solvents used in DAC through a combination of vibrational sum frequency generation spectroscopy and molecular dynamics simulations. This study revealed that the absorption of atmospheric CO2 has antagonistic effects on subsequent capture events that are driven by changes in bulk pH and specific ion effects that feedback on surface organization and interactions. Among the three AAs (leucine, valine, and phenylalanine) studied, we identify and separate behaviors from CO2 loading, chemical changes, variations in pH, and specific ion effects that tune structural and chemical degrees of freedom at the air-aqueous interface. The fundamental mechanistic findings described here are anticipated to enable new approaches to DAC based on exploiting interfaces as a tool to address climate change.

13.
Mar Pollut Bull ; 187: 114567, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36640495

RESUMO

Resting cysts of dinoflagellates seed harmful algal blooms (HABs) and their geographic expansion, which makes it fundamentally important to obtain comprehensive inventories of dinoflagellate resting cysts in HABs-prone regions. The Yellow Sea (YS) of China has observed numerous outbreaks of dinoflagellate HABs with some novel species recorded recently indicating an underestimated HABs-causing species diversity. We report our investigation of dinoflagellate cysts of YS via an approach combining metabarcoding sequencing and single-cyst morpho-molecular identification, which identified many novel cyst species and a significant controlling effect of the Yellow Sea Cold Water Mass on cyst composition. The metabarcoding and single cyst-based sequencing detected 11 cyst species never being unambiguously reported in China, 10 never reported as cyst producers, and 3 HABs-causing species never reported from YS. Our detections of many potentially toxic or HABs-causative, particularly novel, cysts and distribution pattern provide important insights into the risks and ecology of dinoflagellate HABs.


Assuntos
Cistos , Dinoflagellida , Humanos , Proliferação Nociva de Algas , Ecologia , China , Água do Mar
14.
Nat Prod Res ; 37(9): 1411-1415, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34856841

RESUMO

A new chamigrane sesquiterpene, albocimea A (1), and one known compound, 6-hydroxy-8-methoxy-3S,5-dimethylisochroman (2), were isolated from the rice fermentation of the fungus Antrodiella albocinnamomea. The structure of new compound was elucidated by extensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Both compounds were evaluated for their cytotoxicity against five human cancer cell lines, but no significant cytotoxicity was found (IC50 values > 40 µM).


Assuntos
Oryza , Sesquiterpenos , Humanos , Estrutura Molecular , Fermentação , Sesquiterpenos/química
15.
International Eye Science ; (12): 1627-1633, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-987880

RESUMO

AIM: To scrutinize the role of the Wnt/β-catenin signaling pathway in the epithelial-mesenchymal transition(EMT)of lens epithelial cells under hypoxic conditions, and to further analyze the effect of Dickkopf-1(DKK-1)expression on EMT of lens epithelial cells.METHODS: Human lens epithelial cells(HLEB3 cells)were propagated in vitro and then separated into two groups: one exposed to standard oxygen levels, added DMEM culture solution containing 10% FBS(normoxic group)and another subjected to low oxygen levels(hypoxic group). The hypoxic condition was emulated by applying a concentration of 100 μmol/L cobalt chloride(CoCl2)for 6, 12, 24, and 48h. The utilization of immunofluorescence staining enabled the detection of Wnt3a and DKK-1 expressions, along with the expression and localization of β-catenin protein in these groups. The expression of DKK-1 mRNA was discerned by quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS: Immunofluorescence assays indicated an escalating trend in the Wnt3a and DKK-1 protein expression, which corresponded with the increasing duration of hypoxia. Likewise, an intensified nuclear accumulation of β-catenin protein was observed to be directly proportional to the length of hypoxia treatment. The qRT-PCR demonstrated that the difference in DKK-1 mRNA expression between the normoxic group and the group exposed to hypoxia for 6h was not statistically significant(P>0.05), whereas the DKK-1 mRNA expression of the 12, 24, and 48h hypoxia groups were significantly increased(P<0.001).CONCLUSION: Hypoxia can activate Wnt/β-catenin pathway in lens epithelial cells and induce the expression of DKK-1, thus regulating the Wnt/β-catenin pathway and affecting the EMT process.

16.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-995641

RESUMO

Objective:To investigate the relationship between age-adjusted Charlson comorbidity index (aCCI) and ischemic stroke in patients with ophthalmic artery occlusion (OAO) or retinal artery occlusion (RAO).Methods:A single center retrospective cohort study. Seventy-four patients with OAO or RAO diagnosed by ophthalmology examination in Shenzhen Second People's Hospital from June 2004 to December 2020 were included in the study. The baseline information of patients were collected and aCCI was used to score the patients' comorbidity. The outcome was ischemic stroke. The median duration of follow-up was 1 796.5 days. According to the maximum likelihood ratio of the two-piecewise COX regression model and the recursive algorithm, the aCCI inflection point value was determined to be 6, and the patients were divided into low aCCI group (<6 points) and high aCCI group (≥6 points). A Cox regression model was used to quantify the association between baseline aCCI and ischemic stroke.Results:Among the 74 patients, 53 were males and 21 were females, with the mean age of (55.22±14.18) (19-84) years. There were 9 patients of OAO and 65 patients of RAO. The aCCI value ranges from 1 to 10 points, with a median of 3 points. There were 63 patients (85.14%, 63/74) in the low aCCI group and 11 patients (14.86%, 11/74) in the high aCCI group. Since 2 patients could not determine the time from baseline to the occurrence of outcome events, 72 patients were included for Cox regression analysis. The results showed that 16 patients (22.22%, 16/72) had ischemic stroke in the future. The baseline aCCI in the low aCCI group was significantly associated with ischemic stroke [hazard ratio ( HR)=1.76, 95% confidence interval ( CI) 1.21-2.56, P=0.003], and for every 1 point increase in baseline aCCI, the risk of future ischemic stroke increased by 76% on average. The baseline aCCI in the high aCCI group had no significant correlation with the ischemic stroke ( HR=0.66, 95% CI 0.33-1.33, P=0.247). Conclusions:aCCI score is an important prognostic information for patients with OAO or RAO. A higher baseline aCCI score predicts a higher risk of ischemic stroke, and the association has a saturation effect.

17.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991470

RESUMO

Objective:To investigate the application effect of Mini-Clinical Evaluation Exercise (Mini-CEX) combined with direct observation of procedural skills (DOPS) in standardized training of emergency medicine guided by professional physician qualification examination.Methods:Based on the time of emergency medicine teaching reform in Ruikang Hospital Affiliated to Guangxi University of Chinese Medicine, 32 standardized training residents in Emergency Department before September 2020 were included as control group and were given traditional teaching, and 32 standardized training residents after September 2020 were included as observation group and were given Mini-CEX combined with DOPS teaching under the guidance of professional physician qualification examination. The two groups were compared in terms of Mini-CEX score, DOPS score, assessment score of comprehensive emergency skills, pass rate of professional physician qualification examination, and comprehensive teaching quality. SPSS 25.00 was used to perform the t-test and the chi-square test. Results:Compared with the control group after training, the observation group had significantly higher scores of Mini-CEX, DOPS, and comprehensive emergency skill assessment ( P<0.05). There were no significant differences between the two groups in the pass rates of theoretical and practical examinations in professional physician qualification examination, and the observation group had a significantly higher total pass rate than the control group ( P<0.05). The observation group had significantly higher comprehensive teaching quality scores than the control group ( P<0.05). Conclusion:Mini-CEX combined with DOPS guided by professional physician qualification examination can help to improve the teaching effectiveness of standardized training residents in emergency, enhance their comprehensive skills and emergency professional skills, achieve a relatively high pass rate of professional physician qualification examination, and improve their post competency, and thus it holds promise for clinical application.

18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-970476

RESUMO

This study aimed to investigate the effects of nanoparticles PLGA-NPs and mesoporous silicon nanoparticles(MSNs) of different stiffness before and after combination with menthol or curcumol on the mechanical properties of bEnd.3 cells. The particle size distributions of PLGA-NPs and MSNs were measured by Malvern particle size analyzer, and the stiffness of the two nanoparticles was quantified by atomic force microscopy(AFM). The bEnd.3 cells were cultured in vitro, and the cell surface morphology, roughness, and Young's modulus were examined to characterize the roughness and stiffness of the cell surface. The changes in the mechanical properties of the cells were observed by AFM, and the structure and expression of cytoskeletal F-actin were observed by a laser-scanning confocal microscope. The results showed that both nanoparticles had good dispersion. The particle size of PLGA-NPs was(98.77±2.04) nm, the PDI was(0.140±0.030), and Young's modulus value was(104.717±8.475) MPa. The particle size of MSNs was(97.47±3.92) nm, the PDI was(0.380±0.016), and Young's modulus value was(306.019±8.822) MPa. The stiffness of PLGA-NPs was significantly lower than that of MSNs. After bEnd.3 cells were treated by PLGA-NPs and MSNs separately, the cells showed fine pores on the cell surface, increased roughness, decreased Young's modulus, blurred and broken F-actin bands, and reduced mean gray value. Compared with PLGA-NPs alone, PLGA-NPs combined with menthol or curcumol could allow deepened and densely distributed surface pores of bEnd.3 cells, increase roughness, reduce Young's modulus, aggravate F-actin band breakage, and diminish mean gray value. Compared with MSNs alone, MSNs combined with menthol could allow deepened and densely distributed surface pores of bEnd.3 cells, increase roughness, reduce Young's modulus, aggravate F-actin band breakage, and diminish mean gray value, while no significant difference was observed in combination with curcumol. Therefore, it is inferred that the aromatic components can increase the intracellular uptake and transport of nanoparticles by altering the biomechanical properties of bEnd.3 cells.


Assuntos
Animais , Camundongos , Mentol/farmacologia , Actinas/metabolismo , Células Endoteliais/metabolismo , Nanopartículas/química
19.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36499364

RESUMO

Similar to the seeds of higher plants, resting cysts, a non-motile, benthic, and dormant stage in the life history of many dinoflagellate species, play vital roles via germination in the seasonal dynamics and particularly the initiation of harmful algal blooms (HABs) of dinoflagellates. It is thus crucial for resting cysts to balance between the energetic catabolism for viability maintenance and the energy preservation for germination during their dormancy. Despite this importance, studies on how resting cysts of dinoflagellates accomplish energetic metabolism in marine sediment have been virtually absent. In this study, using the cosmopolitan HABs-causing species Scrippsiella acuminata as a representative, we measured the transcriptional activity of the most efficient pathway of the energy catabolism tricarboxylic acid (TCA) cycle, cell viability (via neutral red staining), and the cellular ATP content of resting cysts under a set of mock conditions in marine sediments (e.g., 4 °C, darkness, and anoxia) for a maximum period of one year. Based on the correlation analyses among the expression levels of genes, cyst viability, and ATP content, we revealed that the TCA cycle was still a crucial pathway of energetic catabolism for resting cysts under aerobic conditions, and its expression was elevated at higher temperatures, light irradiation, and the early stage of dormancy. Under anaerobic conditions, however, the TCA cycle pathway ceased expression in resting cysts, as also supported by ATP measurements. Our results have laid a cornerstone for the comprehensive revelation of the energetic metabolism and biochemical processes of dormancy of resting cysts in marine sediments.


Assuntos
Cistos , Dinoflagellida , Humanos , Dinoflagellida/genética , Proliferação Nociva de Algas , Sedimentos Geológicos , Trifosfato de Adenosina
20.
Ann Transl Med ; 10(22): 1218, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36544667

RESUMO

Background: Neuroinflammation mediated by microglia plays a key role in the pathogenesis of Parkinson's disease (PD), and our previous studies showed this was significantly inhibited by enhanced autophagy. In the autophagy pathway, Bcl2-associated athanogene (BAG)3 is a prominent co-chaperone, and we have shown BAG3 can regulate autophagy to clear the PD pathogenic protein α-synuclein. However, the connection between BAG3 and microglia mediated neuroinflammation is not clear. Methods: In this study, we explored whether BAG3 regulated related neuroinflammation and its original mechanism in PD. An inflammatory model of PD was established by injecting adeno-associated virus (AAV)-BAG3 into the bilateral striatum of C57BL/6 male mice to induce overexpression of BAG3, followed by injection of lipopolysaccharide (LPS). The striatum was extracted at 3 days after injection of LPS for Western blotting and reverse transcription quantitative polymerase chain reaction (RT-qPCR), and immunohistochemical staining was performed at 21 days after injection. At the same time, LPS was used to induce activation of BV2 cells to verify the effect of BAG3 in vitro. Results: Overexpression of BAG3 reduced LPS-induced pyroptosis by reducing activation of caspase-1, the NOD-like receptor family, and the pyrin domain-containing 3 (NLRP3) inflammasome, and by release of interleukin (IL)-1ß and tumor necrosis factor (TNF)-α. The LPS-induced inflammatory environment inhibits autophagy, and overexpression of BAG3 can restore autophagy, which may be the mechanism by which BAG3 reduces neuronal inflammation in PD. Conclusions: Our results demonstrate BAG3 promotes autophagy and suppresses NLRP3 inflammasome formation in PD.

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