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1.
Small ; 20(31): e2311675, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38441359

RESUMEN

The high oxygen electrocatalytic overpotential of flexible cathodes due to sluggish reaction kinetics result in low energy conversion efficiency of wearable zinc-air batteries (ZABs). Herein, lignin, as a 3D flexible carbon-rich macromolecule, is employed for partial replacement of polyacrylonitrile and constructing flexible freestanding air electrodes (FFAEs) with large amount of mesopores and multi-hollow channels via electrospinning combined with annealing strategy. The presence of lignin with disordered structure decreases the graphitization of carbon fibers, increases the structural defects, and optimizes the pore structure, facilitating the enhancement of electron-transfer kinetics. This unique structure effectively improves the accessibility of graphitic-N/pyridinic-N with oxygen reduction reaction (ORR) activity and pyridinic-N with oxygen evolution reaction (OER) activity for FFAEs, accelerating the mass transfer process of oxygen-active species. The resulting N-doped hollow carbon fiber films (NHCFs) exhibit superior bifunctional ORR/OER performance with a low potential difference of only 0.60 V. The rechargeable ZABs with NHCFs as metal-free cathodes possess a long-term cycling stability. Furthermore, the NHCFs can be used as FFAEs for flexible ZABs which have a high specific capacity and good cycling stability under different bending states. This work paves the way to design and produce highly active metal-free bifunctional FFAEs for electrochemical energy devices.

2.
Exp Dermatol ; 33(1): e14948, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37950506

RESUMEN

Dermal papilla cells (DPCs) undergo premature ageing in androgenetic alopecia and senescent alopecia. As critical components of hair follicle reconstruction, DPCs are also prone to senescence in vitro, resulting in a diminished hair follicle inductivity capacity. Dermal sheath cup cells (DSCCs), a specific subset of hair follicle mesenchymal stem cells, intimately linked to the function of DPCs. The primary objective of this research is to investigate the anti-ageing effect of exosomes derived from DSCCs (ExoDSCCs ) on DPCs. Exosomes were utilized to treat H2 O2 -induced DPCs or long-generation DPCs(P10). Our findings demonstrate that ExoDSCCs(P3) promote the proliferation, viability and migration of senescent DPCs while inhibiting cell apoptosis. The expression of senescence marker SA-ß-Gal were significantly downregulated in senescent DPCs. When treated with ExoDSCCs(P3) , expression of inducibility related markers alkaline phosphatase and Versican were significantly upregulated. Additionally, ExoDSCCs(P3) activated the Wnt/ß-catenin signalling in vitro. In patch assay, ExoDSCCs(P3) significantly promoted hair follicle reconstruction in senescent DPCs. In summary, our work highlights that ExoDSCCs(P3) may restore the biological functions and improve the hair follicle induction ability of senescent DPCs. Therefore, ExoDSCCs(P3) may represent a new strategy for intervening in the ageing process of DPCs, contributing to the prevention of senile alopecia.


Asunto(s)
Exosomas , Folículo Piloso , Humanos , Folículo Piloso/metabolismo , Dermis/metabolismo , Células Cultivadas , Alopecia/metabolismo , Envejecimiento , Regeneración , Proliferación Celular
3.
Inorg Chem ; 63(21): 9735-9752, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38728376

RESUMEN

A series of Ru(II) complexes incorporating two 4,4'-bis(trifluoromethyl)-2,2'-bipyridine (4,4'-btfmb) coligands and thienyl-appended imidazo[4,5-f][1,10]phenanthroline (IP-nT) ligands was characterized and assessed for phototherapy effects toward cancer cells. The [Ru(4,4'-btfmb)2(IP-nT)]2+ scaffold has greater overall redox activity compared to Ru(II) polypyridyl complexes such as [Ru(bpy)3]2+. Ru-1T-Ru-4T have additional oxidations due to the nT group and additional reductions due to the 4,4'-btfmb ligands. Ru-2T-Ru-4T also exhibit nT-based reductions. Ru-4T exhibits two oxidations and eight reductions within the potential window of -3 to +1.5 V. The lowest-lying triplets (T1) for Ru-0T-2T are metal-to-ligand charge-transfer (3MLCT) excited states with lifetimes around 1 µs, whereas T1 for Ru-3T-4T is longer-lived (∼20-24 µs) and of significant intraligand charge-transfer (3ILCT) character. Phototoxicity toward melanoma cells (SK-MEL-28) increases with n, with Ru-4T having a visible EC50 value as low as 9 nM and PI as large as 12,000. Ru-3T and Ru-4T retain some of this activity in hypoxia, where Ru-4T has a visible EC50 as low as 35 nM and PI as high as 2900. Activity over six biological replicates is consistent and within an order of magnitude. These results demonstrate the importance of lowest-lying 3ILCT states for phototoxicity and maintaining activity in hypoxia.

4.
Macromol Rapid Commun ; : e2400235, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742492

RESUMEN

Compared with normal stimulus such as light and heat, ultrasonic possesses much deeper penetration into tissues and organs and has lower scattering in heterogeneous systems as a noninvasive stimulus. Reversible addition-fragmentation chain-transfer polymerization (RAFT) in aqueous media is performed in a commercial ultrasonic wash bath with 40 kHz frequency ultrasonic, in the presence of piezoelectric tetragonal BaTiO3 (BTO) nanoparticles. Owing to the electron transfer from BTO under the ultrasonic action, the water can be decomposed to produce hydroxyl radical (HO•) and initiate the RAFT polymerization (piezo-RAFT). The piezo-RAFT polymerization exhibits features of controllable and livingness, such as linear increase of molar mass and narrow molar mass distributions (Mw/Mn < 1.20). Excellent temporal control of the polymerization and the chain fidelity of polymers are illustrated by "ON and OFF" experiment and chain extension, separately. Moreover, this ultrasonic-driven piezoelectric-induced RAFT polymerization in aqueous media can be directly used for the preparation of piezoelectric hydrogel which have potential application for stress sensor.

5.
Chirality ; 36(8): e23701, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39034270

RESUMEN

Azobenzene (Azo) liquid-crystalline polymers are intriguing due to their unique photo-induced isomerization and supramolecular chirality. However, clarification on multicomponent chiral induction towards Azo polymers remains ambiguous and challenging. Herein, chiral solvents and amines were employed to control the chiroptical activity of achiral Azo polymers. Methyl L-/D-lactate was added as the poor solvent and chiral inducer to achieve the first chiral induction in Azo aggregates. Chiral amines were utilized for the second chiral induction based on the acid-base interactions between the carboxyl groups of polymers and amines. The chiral enhancement and inversion of Azo units could be observed through the synergistic or antagonistic effect between solvents and amines. The impacts of solvent, chemical structures, feed ratio, enantiomeric excess, and temperature on supramolecular chirality were systematically studied. Furthermore, this system displayed the chiroptical switching property and chiral recovery under reversible irradiation.

6.
Ecotoxicol Environ Saf ; 283: 116841, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39128448

RESUMEN

Lewy body disease (LBD), one of the most common neurodegenerative diseases (NDDs), is characterized by excessive accumulation of α-synuclein (α-syn) in neurons. In recent years, environmental factors such as exposure to herbicides and pesticides have been attributed to the development of this condition. While majority of the studies on neurotoxic effects of paraquat (PQ) have focused on α-syn-mediated neuronal damage in the early stages of α-syn accumulation in neurons, efforts to explore the key target for α-syn degradation are limited. Recent research has suggested that histone deacetylase 6 (HDAC6) might possibly regulate amyloid clearance, and that the metabolism of compounds in neurons is also directly affected by axonal transport in neurons. Dynein predominantly mediates reverse transportation of metabolites and uptake of signal molecules and other compounds at the end of axons, which is conducive to the reuse of cell components. However, the role of interaction of dynein with HDAC6 in metabolites transport is still unclear. Therefore, this study aimed to investigate the role of HDAC6 in α-syn accumulation/clearance in neurons and the associated possible influencing factors. The results revealed that HDAC6 could transport ubiquitinated α-syn, bind to dynein, form an aggresome, and relocate to the center of the microtubule tissue, ultimately reducing abnormal accumulation of α-syn. However, PQ treatment resulted in HDAC6 upregulation, causing abnormal aggregation of α-syn. Taken together, these findings indicated that PQ exposure caused abnormal accumulation of α-syn and decreased effective degradation of α-syn by HDAC6-mediated aggresome-autophagy-lysosome pathway.


Asunto(s)
Dineínas , Histona Desacetilasa 6 , Paraquat , alfa-Sinucleína , Histona Desacetilasa 6/metabolismo , Paraquat/toxicidad , alfa-Sinucleína/metabolismo , Animales , Dineínas/metabolismo , Herbicidas/toxicidad , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Transporte Axonal/efectos de los fármacos , Ratones
7.
Environ Toxicol ; 39(3): 1874-1888, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38189626

RESUMEN

Paraquat (PQ), is characterized by neurotoxicity, which increases the potential risk of Parkinson's disease (PD) exposure in the long-term and low doses. Triggering microglia activation and neuroinflammation is deemed an early event resulting in PD. However, the underlying pathogenesis of PD by PQ is not clear yet. In this article, C57BL/6J mice treated with PQ could successfully act out Parkinson-like. In addition, we observed the fluorescence intensity enhancement of Iba-1 activated microglia with released pro-inflammatory, all ahead of both the damage of dopaminergic neurons in the substantia nigra and corpus striatum of the brain. Surprisingly, the injection of minocycline before PQ for many hours not only can effectively improve the neurobehavioral symptoms of mice but inhibit the activation of microglia and the release of pro-inflammatory substances, even controlling the gradual damage and loss of neurons. A further mechanism of minocycline hampered the expression levels of key signaling proteins PI3K, PDK1, p-AKT, and CD11b (the receptor of microglia membrane recognition), while a large number of inflammatory factors. Our results suggested that the CD11b/PI3K/NOX2 pathway may be a clue that microglia-mediated inflammatory responses and neuronal damage in a PQ-induced abnormal behavior Parkinson-like mouse.


Asunto(s)
Paraquat , Enfermedad de Parkinson , Animales , Ratones , Paraquat/toxicidad , Microglía , Minociclina/metabolismo , Minociclina/farmacología , Ratones Endogámicos C57BL , Neuronas Dopaminérgicas/metabolismo , Neuronas Dopaminérgicas/patología , Fosfatidilinositol 3-Quinasas/metabolismo
8.
Sensors (Basel) ; 24(6)2024 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-38544169

RESUMEN

In this paper, we explore the secrecy performance of a visible light communication (VLC) system consisting of distributed light-emitting diodes (LEDs) and multiple users (UEs) randomly positioned within an indoor environment while considering the presence of an eavesdropper. To enhance the confidentiality of the system, we formulate a problem of maximizing the sum secrecy rate for UEs by searching for an optimal LED for each UE. Due to the non-convex and non-continuous nature of this security maximization problem, we propose an LED selection algorithm based on tabu search to avoid getting trapped in local optima and expedite the search process by managing trial vectors from previous iterations. Moreover, we introduce three LED selection strategies with a low computational complexity. The simulation results demonstrate that the proposed algorithm achieves a secrecy performance very close to the global optimal value, with a gap of less than 1%. Additionally, the proposed strategies exhibit a performance gap of 28% compared to the global optimal.

9.
Surg Innov ; 31(1): 82-91, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37916497

RESUMEN

Learning surgical skills require critical visual-spatial motor skills. Current learning methods employ costly and limited in-person teaching in addition to supplementation by videos, textbooks, and cadaveric labs. Increasingly limited healthcare resources and in-person training has led to growing concerns for skills acquisition of trainees. Recent Mixed Reality (MR) devices offer an attractive solution to these resource barriers by providing three-dimensional holographic representations of reality that mimic in-person experiences in a portable, individualized, and cost-effective form. We developed and evaluated two holographic MR models to explore the feasibility of visual-spatial motor skill acquisition from a technical development, learning, and usability perspective. In our first, a pair of holographic hands were created and projected in front of the trainee, and participants were evaluated on their ability to learn complex hand motions in comparison to traditional methods of video and apprenticeship-based learning. The second model displayed a 3D holographic model of the middle and inner ear with labeled anatomical structures which users could explore and user experience feedback was obtained. Our studies demonstrated that scores between MR and apprenticeship learning were comparable. All felt MR was an effective learning tool and most noted that the MR models were better than existing didactic methods of learning. Identified advantages of MR included the ability to provide true 3D spatial representation, improved visualization of smaller structures in detail by upscaling the models, and improved interactivity. Our results demonstrate that holographic learning is able to mimic in-person learning for visual-spatial motor skills and could be a new effective form of self-directed apprenticeship learning.


Asunto(s)
Realidad Aumentada , Humanos , Destreza Motora , Mentores , Retroalimentación
10.
Fa Yi Xue Za Zhi ; 40(3): 245-253, 2024 Jun 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-39166305

RESUMEN

OBJECTIVES: To describe the current state of research and future research hotspots through a metrological analysis of the literature in the field of forensic anthropological remains identification research. METHODS: The data retrieved and extracted from the Web of Science Core Collection (WoSCC), the core database of the Web of Science information service platform (hereinafter referred to as "WoS"), was used to analyze the trends and topic changes in research on forensic identification of human remains from 1991 to 2022. Network visualisation of publication trends, countries (regions), institutions, authors and topics related to the identification of remains in forensic anthropology was analysed using python 3.9.2 and Gephi 0.10. RESULTS: A total of 873 papers written in English in the field of forensic anthropological remains identification research were obtained. The journal with the largest number of publications was Forensic Science International (164 articles). The country (region) with the largest number of published papers was China (90 articles). Katholieke Univ Leuven (Netherlands, 21 articles) was the institution with the largest number of publications. Topic analysis revealed that the focus of forensic anthropological remains identification research was sex estimation and age estimation, and the most commonly studied remains were teeth. CONCLUSIONS: The volume of publications in the field of forensic anthropological remains identification research has a distinct phasing. However, the scope of both international and domestic collaborations remains limited. Traditionally, human remains identification has primarily relied on key areas such as the pelvis, skull, and teeth. Looking ahead, future research will likely focus on the more accurate and efficient identification of multiple skeletal remains through the use of machine learning and deep learning techniques.


Asunto(s)
Bibliometría , Restos Mortales , Antropología Forense , Humanos , Antropología Forense/métodos , Publicaciones/estadística & datos numéricos
11.
Inorg Chem ; 62(51): 21181-21200, 2023 Dec 25.
Artículo en Inglés | MEDLINE | ID: mdl-38079387

RESUMEN

Ru(II) polypyridyl complexes have gained widespread attention as photosensitizers for photodynamic therapy (PDT). Herein, we systematically investigate a series of the type [Ru(phen)2(IP-nT)]2+, featuring 1,10-phenanthroline (phen) coligands and imidazo[4,5-f][1,10]phenanthroline ligands tethered to n = 0-4 thiophene rings (IP-nT). The complexes were characterized and investigated for their electrochemical, spectroscopic, and (photo)biological properties. The electrochemical oxidation of the nT unit shifted by -350 mV as n = 1 → 4 (+920 mV for Ru-1T, +570 mV for Ru-4T); nT reductions were observed in complexes Ru-3T (-2530 mV) and Ru-4T (-2300 mV). Singlet oxygen quantum yields ranged from 0.53 to 0.88, with Ru-3T and Ru-4T being equally efficient (∼0.88). Time-resolved absorption spectra of Ru-0T-1T were dominated by metal-to-ligand charge-transfer (3MLCT) states (τTA = 0.40-0.85 µs), but long-lived intraligand charge-transfer (3ILCT) states were observed in Ru-2T-4T (τTA = 25-148 µs). The 3ILCT energies of Ru-3T and Ru-4T were computed to be 1.6 and 1.4 eV, respectively. The phototherapeutic efficacy against melanoma cells (SK-MEL-28) under broad-band visible light (400-700 nm) increases as n = 0 → 4: Ru-0T was inactive up to 300 µM, Ru-1T-2T were moderately active (EC50 ∼ 600 nM, PI = 200), and Ru-3T (EC50 = 57 nM, PI > 1100) and Ru-4T (EC50 = 740 pM, PI = 114,000) were the most phototoxic. The activity diminishes with longer wavelengths of light and is completely suppressed for all complexes except Ru-3T and Ru-4T in hypoxia. Ru-4T is the more potent and robust PS in 1% O2 over seven biological replicates (avg EC50 = 1.3 µM, avg PI = 985). Ru-3T exhibited hypoxic activity in five of seven replicates, underscoring the need for biological replicates in compound evaluation. Singlet oxygen sensitization is likely responsible for phototoxic effects of the compounds in normoxia, but the presence of redox-active excited states may facilitate additional photoactive pathways for complexes with three or more thienyl groups. The 3ILCT state with its extended lifetime (30-40× longer than the 3MLCT state for Ru-3T and Ru-4T) implicates its predominant role in photocytotoxicity.


Asunto(s)
Fotoquimioterapia , Rutenio , Fenantrolinas/farmacología , Fenantrolinas/química , Oxígeno Singlete/química , Rutenio/farmacología , Rutenio/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/química , Ligandos
12.
Macromol Rapid Commun ; 44(3): e2200693, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36250510

RESUMEN

Multiple and two-way reversible shape memory polymers (M/2W-SMPs) are highly promising for many fields due to large deformation, lightweight, strong recovery stress, and fast response rates. Herein, a semi-crystalline block poly(urethane-urea-amide) elastomers (PUUAs) are prepared by the copolymerization of isocyanate-terminated polyurethane (OPU) and amino-terminated oligomeric polyamide-1212 (OPA). PUUAs, composed of OPA as stationary phase and PTMEG as reversible phase, exhibit excellent rigidity, flexibility, and resilience, and cPUUA-C7 -S25 exhibits the best tensile property with strength of 10.3 MPa and elongation at break of 360.2%. Besides, all the PUUAs possess two crystallization/melting temperatures and a glass transition temperature, which endow PUUAs with multiple and reversible two-way shape memory effect (M/2W-SME). Physically crosslinked PUUA-C0 -S25 exhibits excellent dual and triple shape memory, and micro chemically crosslinked cPUUA-C7 -S25 further shows quadruple shape memory behavior. Additionally, both PUUA-C0 -S25 and cPUUA-C7 -S25 have 2W-SME. Intriguingly, cPUUA-C7 -S25 can achieve a higher temperature (up to 165 °C) SME, which makes it suitable for more complex and changeable applications. Based on the advantages of M/2W-SME, a temperature-responsive application scenario where PUUAs can transform spontaneously among different shapes is designed. These unique M/2W-SME and high-temperature SME will enable the applications of high-temperature sensors, actuators, and aerospace equipment.


Asunto(s)
Elastómeros , Polímeros , Polímeros/química , Amidas , Urea , Poliuretanos/química
13.
Proc Natl Acad Sci U S A ; 117(13): 7038-7043, 2020 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-32179672

RESUMEN

Paleoclimate research has built a framework for Earth's climate changes over the past 65 million years or even longer. However, our knowledge of weather-timescale extreme events (WEEs, also named paleoweather), which usually occur over several days or hours, under different climate regimes is almost blank because current paleoclimatic records rarely provide information with temporal resolution shorter than monthly scale. Here we show that giant clam shells (Tridacna spp.) from the tropical western Pacific have clear daily growth bands, and several 2-y-long (from January 29, 2012 to December 9, 2013) daily to hourly resolution biological and geochemical records, including daily growth rate, hourly elements/Ca ratios, and fluorescence intensity, were obtained. We found that the pulsed changes of these ultra-high-resolution proxy records clearly matched with the typical instrumental WEEs, for example, tropical cyclones during the summer-autumn and cold surges during the winter. When a tropical cyclone passes through or approaches the sampling site, the growth rate of Tridacna shell decreases abruptly due to the bad weather. Meanwhile, enhanced vertical mixing brings nutrient-enriched subsurface water to the surface, resulting in a high Fe/Ca ratio and strong fluorescence intensity (induced by phytoplankton bloom) in the shell. Our results demonstrate that Tridacna shell has the potential to be used as an ultra-high-resolution archive for paleoweather reconstructions. The fossil shells living in different geological times can be built as a Geological Weather Station network to lengthen the modern instrumental data and investigate the WEEs under various climate conditions.


Asunto(s)
Bivalvos/química , Bivalvos/crecimiento & desarrollo , Clima Extremo , Paleontología/métodos , Animales
14.
Ecotoxicol Environ Saf ; 252: 114583, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36736232

RESUMEN

Atrazine (ATR) is a widely applied herbicide which was named an environmental endocrine disrupting chemical (EDC). Increasing evidence indicates ATR causes neurotoxic effects resulting in central nervous system (CNS) disease. As the primary immunocytes in the CNS, microglia cells carry out their phagocytosis to maintain the CNS microenvironment by preventing damage from healthy cells. However, the mechanism in which ATR affects the phagocytic function of microglia remains unclear. The present study was designed to investigate the effect of ATR on the phagocytosis of microglia. BV-2 cells and primary microglia selected as microglial models in which BV-2 cells were administrated by ATR at different concentrations (0, 4, 8, 16 µM) for 24 h. Results demonstrated ATR dose-dependently increased the expression of ionized calcium binding adapter molecule 1 (Iba-1), indicating that microglia were activated. Microglial phagocytotic activity induced by ATR fluctuated at the different time points, accompanied by fluctuations in membrane receptor MERTK and cytoplasmic lysosomal marker LAMP1 (two markers related to cell phagocytosis). In this period, the expression of iNOS gradually increased. A mechanistic study further demonstrated that the translocation of High Mobility Group Protein-B1 (HMGB1) from nucleus to cytoplasm in the BV-2 and primary microglial cells induced by ATR, and the process showed a positive correlation with phagocytosis activity of BV-2 cells induced by ATR (r = 0.8030, P = 0.05; α = 0.1). ATR was also shown to spur the acetylation of HMGB1 by breaking the balance between acetylase P300 and deacetylase SIRT1. Unexpectedly, the inhibition of acetylating HMGB1 by resveratrol (Res) was effectively retained by HMGB1 in the nucleus, reversed the SIRT1 and MERTK expression, and enhanced the phagocytosis activity in BV-2 cells. Our results suggested that ATR exposure influenced microglial phagocytosis by acetylating HMGB1 further translocated it in the nucleoplasm.


Asunto(s)
Atrazina , Proteína HMGB1 , Microglía , Atrazina/toxicidad , Atrazina/metabolismo , Sirtuina 1/metabolismo , Tirosina Quinasa c-Mer/metabolismo , Proteína HMGB1/metabolismo , Fagocitosis
15.
Ecotoxicol Environ Saf ; 255: 114780, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36933483

RESUMEN

Atrazine (ATR) is one of the herbicides widely used worldwide. Meanwhile, it is an environmental endocrine disruptor that can cross the blood-brain barrier and cause damage to the endocrine-nervous system, especially by affecting the normal secretion of dopamine (DA). Regrettably, effector markers and cascade response mechanisms in damaged dopaminergic neurons induced by ATR exposure remain elusive. In this paper, we focus on investigating aggregation and position change of transactive response DNA-binding protein-43 (TDP-43) after ATR exposure, and illustrating whether TDP-43 can serve as a potential marker of mitochondrial dysfunction which causes damage to dopaminergic neurons. In our study, we used rat adrenal pheochromocytoma cell line 12 (PC12) to establish an in vitro model of dopaminergic neurons. After PC12 was intervened by ATR, we found reduced DA cycling and DA levels, and that TDP-43 aggregated continuously in the cytoplasm and then translocated to mitochondria. Furthermore, the studies we have performed showed that the translocation can cause mitochondrial dysfunction through activating the unfolded mitochondrial protein response (UPRmt), ultimately causing damage to dopaminergic neuron. The research we have done suggests that TDP-43 can serve as a potential effector marker of dopaminergic neuron damaged caused by ATR exposure.


Asunto(s)
Atrazina , Herbicidas , Ratas , Animales , Atrazina/toxicidad , Atrazina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Herbicidas/toxicidad , Herbicidas/metabolismo , Dopamina/metabolismo , Proteínas de Unión al ADN/metabolismo
16.
Angew Chem Int Ed Engl ; 62(17): e202301452, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-36827484

RESUMEN

This study employs TLD1433, a RuII -based photodynamic therapy (PDT) agent in human clinical trials, as a benchmark to establish protocols for studying the excited-state dynamics of photosensitizers (PSs) in cellulo, in the local environment provided by human cancer cells. Very little is known about the excited-state properties of any PS in live cells, and for TLD1433, it is terra incognita. This contribution targets a general problem in phototherapy, which is how to interrogate the light-triggered, function-determining processes of the PSs in the relevant biological environment, and establishes methodological advances to study the ultrafast photoinduced processes for TLD1433 when taken up by MCF7 cells. We generalize the methodological developments and results in terms of molecular physics by applying them to TLD1433's analogue TLD1633, making this study a benchmark to investigate the excited-state dynamics of phototoxic compounds in the complex biological environment.


Asunto(s)
Fotoquimioterapia , Rutenio , Humanos , Fármacos Fotosensibilizantes/uso terapéutico , Células MCF-7
17.
BMC Genomics ; 23(1): 506, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35831806

RESUMEN

BACKGROUND: The genus Sporothrix belongs to the order Ophiostomatales and contains mainly saprobic soil and plant fungi, although pathogenic species capable of causing human infections are also present. The whole-genomes of disease-causing species have already been sequenced and annotated but no comprehensive genomic resources for environmental Sporothrix species are available, thus limiting our understanding of the evolutionary origin of virulence-related genes and pathogenicity. RESULT: The genome assembly of four environmental Sporothrix species resulted in genome size of ~ 30.9 Mbp in Sporothrix phasma, ~ 35 Mbp in S. curviconia, ~ 38.7 Mbp in S. protearum, and ~ 39 Mbp in S. variecibatus, with a variable gene content, ranging from 8142 (S. phasma) to 9502 (S. variecibatus). The analysis of mobile genetic elements showed significant differences in the content of transposable elements within the sequenced genomes, with the genome of S. phasma lacking several class I and class II transposons, compared to the other Sporothrix genomes investigated. Moreover, the comparative analysis of orthologous genes shared by clinical and environmental Sporothrix genomes revealed the presence of 3622 orthogroups shared by all species, whereas over 4200 genes were species-specific single-copy gene products. Carbohydrate-active enzyme analysis revealed a total of 2608 protein-coding genes containing single and/or multiple CAZy domains, resulting in no statistically significant differences among pathogenic and environmental species. Nevertheless, some families were not found in clinical species. Furthermore, for each sequenced Sporothrix species, the mitochondrial genomes was assembled in a single circular DNA molecule, ranging from 25,765 bp (S. variecibatus) to 58,395 bp (S. phasma). CONCLUSION: In this study, we present four annotated genome assemblies generated using PacBio SMRT sequencing data from four environmental species: S. curviconia, S. phasma, S. protearum and S. variecibatus with the aim to provide a starting point for future comparative genome evolution studies addressing species diversification, ecological/host adaptation and origin of pathogenic lineages within the genus Sporothrix.


Asunto(s)
Genoma Mitocondrial , Sporothrix , Secuencia de Bases , Humanos , Filogenia , Análisis de Secuencia de ADN , Sporothrix/genética
18.
J Am Chem Soc ; 144(22): 9817-9826, 2022 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-35617524

RESUMEN

Photoinduced atom transfer radical polymerization (ATRP) has been proved to be a versatile technique for polymer network formation. However, the slow polymerization rates of typical ATRP limited its application in the field of additive manufacturing (3D printing). In this work, we introduced carbon quantum dots (CQDs) for the first time to the ATRP in aqueous media and developed an ultrafast visible-light-induced polymerization system. After optimization, the polymerization could achieve a high monomer conversion (>90%) within 1 min, and the polydispersity index (PDI) of the polymer was lower than 1.25. This system was then applied as the first example of ATRP for the 3D printing of hydrogel through digital light processing (DLP), and the printed object exhibited good dimensional accuracy. Additionally, the excellent and stable optical properties of CQDs also provided interesting photoluminescence capabilities to the printed objects. We deduce this ATRP mediated 3D printing process would provide a new platform for the preparation of functional and stimuli-responsive hydrogel materials.

19.
J Am Chem Soc ; 144(22): 9543-9547, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-34882381

RESUMEN

Tumor hypoxia renders treatments ineffective that are directly (e.g., radiotherapy and photodynamic therapy) or indirectly (e.g., chemotherapy) dependent on tumor oxygenation. This study introduces a ruthenium compound as a light-responsive anticancer agent that is water-soluble, has minimal dark cytotoxicity, is active at concentrations as low as 170 pM in ∼18.5% O2 normoxia and near 10 nM in 1% O2 hypoxia, and exhibits phototherapeutic indices as large as >500,000 in normoxia and >5,800 in 1% O2 hypoxia using broadband visible and monochromatic blue light treatments. These are the largest values reported to date for any compound class. We highlight the response in four different cell lines to improve rigor and reproducibility in the identification of promising clinical candidates.


Asunto(s)
Antineoplásicos , Fotoquimioterapia , Rutenio , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Humanos , Hipoxia/tratamiento farmacológico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Reproducibilidad de los Resultados , Rutenio/farmacología
20.
Opt Express ; 30(5): 7394-7411, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299503

RESUMEN

In this paper, secure transmission over multiple-input single-output visible light communication system under coexistent passive and active eavesdroppers (Eves) is studied. To enhance the achievable secrecy rate of this system given statistical channel state information (CSI) error model for the passive Eves-related channels, a robust artificial-noise (AN) based transmit strategy is proposed and a secrecy rate maximization problem subject to secrecy-outage-probability constraint, sum power constraint, and peak amplitude constraint is formulated. To solve this non-convex problem, a conservative approximation is presented to replace the probabilistic constraint and unbounded CSI error with worst-case secrecy constraints and spherically-bounded CSI errors, respectively. Then, semi-definite relaxation, S-procedure, and a Golden search-based algorithm are proposed to solve the approximated problem with fast convergence and low complexity. Simulation results show that the proposed method outperforms the other AN-aided and non-AN method for the coexistent active and passive Eves case, especially when the power budget is high.

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