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1.
Front Neurol ; 15: 1346858, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560732

RESUMO

Background: Mild cognitive impairment (MCI) is an intermediary condition between typical cognitive decline that occurs owing to aging and dementia. It is necessary to implement an intervention to slow the progression from MCI to Alzheimer's disease. This manuscript reports the protocol for a clinical trial on the effect of acupuncture in patients with MCI. Methods: The trial will be a randomized, prospective, parallel-arm, active-controlled trial. Sixty-four patients with MCI will be randomized to the Rehacom or acupuncture group (n = 32 each). The participants in the acupuncture group will receive electroacupuncture at GV24 (Shenting) and GV20 (Baihui) and acupuncture at EX-HN1 (Sishencong) once (30 min) a day, twice per week for 12 weeks. The patients in the Rehacom group will receive computerized cognitive rehabilitation using RehaCom software once (30 min) daily, twice weekly for 12 weeks. The primary outcome measure is the change in the Montreal Cognitive Assessment Scale score. The secondary outcome measures are the Geriatric Depression Scale, Alzheimer's Disease Assessment Scale-Korean version-cognitive subscale-3 scores, and European Quality of Life Five Dimensions Five Level Scale. The safety outcomes will include the incidence of adverse events, blood pressure, blood chemistry parameters, and pulse rate. The efficacy outcome will be assessed at baseline and at six weeks, 13 weeks, and 24 weeks after baseline. Discussion: The findings of this protocol will provide information regarding the effects of acupuncture on MCI. Clinical trial registration: https://cris.nih.go.kr/cris/search/detailSearch.do?search_lang=E&focus=reset_12&search_page=M&pageSize=10&page=undefined&seq=25579&status=5&seq_group=25579, KCT0008861.

2.
Biochem Biophys Res Commun ; 709: 149823, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38569245

RESUMO

Avian pathogenic Escherichia coli (APEC) causes enormous economic losses and is a primary contributor to the emergence of multidrug resistance (MDR)-related problems in the poultry industry. Bacteriophage (phage) therapy has been successful in controlling MDR, but phage-resistant variants have rapidly emerged through the horizontal transmission of diverse phage defense systems carried on mobile genetic elements. Consequently, while multiple phage cocktails are recommended for phage therapy, there is a growing need to explore simpler and more cost-effective phage treatment alternatives. In this study, we characterized two novel O78-specific APEC phages, φWAO78-1 and φHAO78-1, in terms of their morphology, genome, physicochemical stability and growth kinetics. Additionally, we assessed the susceptibility of thirty-two O78 APEC strains to these phages. We analyzed the roles of highly susceptible cells in intestinal settlement and fecal shedding (susceptible cell-assisted intestinal settlement and shedding, SAIS) of phages in chickens via coinoculation with phages. Furthermore, we evaluated a new strategy, susceptible cell-assisted resistant cell killing (SARK), by comparing phage susceptibility between resistant cells alone and a mixture of resistant and highly susceptible cells in vitro. As expected, high proportions of O78 APEC strains had already acquired multiple phage defense systems, exhibiting considerable resistance to φWAO78-1 and φHAO78-1. Coinoculation of highly susceptible cells with phages prolonged phage shedding in feces, and the coexistence of susceptible cells markedly increased the phage susceptibility of resistant cells. Therefore, the SAIS and SARK strategies were demonstrated to be promising both in vivo and in vitro.


Assuntos
Bacteriófagos , Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Bacteriófagos/genética , Galinhas , Escherichia coli/genética , Colífagos , Morte Celular , Doenças das Aves Domésticas/terapia
3.
Small ; : e2310562, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38431932

RESUMO

In recent years, there has been a substantial surge in the investigation of transition-metal dichalcogenides such as MoS2 as a promising electrochemical catalyst. Inspired by denitrification enzymes such as nitrate reductase and nitrite reductase, the electrochemical nitrate reduction catalyzed by MoS2 with varying local atomic structures is reported. It is demonstrated that the hydrothermally synthesized MoS2 containing sulfur vacancies behaves as promising catalysts for electrochemical denitrification. With copper doping at less than 9% atomic ratio, the selectivity of denitrification to dinitrogen in the products can be effectively improved. X-ray absorption characterizations suggest that two sulfur vacancies are associated with one copper dopant in the MoS2 skeleton. DFT calculation confirms that copper dopants replace three adjacent Mo atoms to form a trigonal defect-enriched region, introducing an exposed Mo reaction center that coordinates with Cu atom to increase N2 selectivity. Apart from the higher activity and selectivity, the Cu-doped MoS2 also demonstrates remarkably improved tolerance toward oxygen poisoning at high oxygen concentration. Finally, Cu-doped MoS2 based catalysts exhibit very low specific energy consumption during the electrochemical denitrification process, paving the way for potential scale-up operations.

4.
ACS Nano ; 18(14): 10302-10311, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38537206

RESUMO

The electrochemical upcycling of nitrate (NO3-) to ammonia (NH3) holds promise for synergizing both wastewater treatment and NH3 synthesis. Efficient stripping of gaseous products (NH3, H2, and N2) from electrocatalysts is crucial for continuous and stable electrochemical reactions. This study evaluated a layered electrocatalyst structure using copper (Cu) dendrites to enable a high curvature and hydrophobicity and achieve a stratified liquid contact at the gas-liquid interface of the electrocatalyst layer. As such, gaseous product desorption or displacement from electrocatalysts was enhanced due to the separation of a wetted reaction zone and a nonwetted zone for gas transfer. Consequently, this electrocatalyst structure yielded a 2.9-fold boost in per-active-site activity compared with that with a low curvature and high hydrophilic counterpart. Moreover, a NH3 Faradaic efficiency of 90.9 ± 2.3% was achieved with nearly 100% NO3- conversion. This high-curvature hydrophobic Cu dendrite was further integrated with a gas-extraction membrane, which demonstrated a comparable NH3 yield from the real reverse osmosis retentate brine.

6.
Cell Rep ; 43(3): 113813, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38393947

RESUMO

Peptidoglycan recognition protein 1 (PGLYRP1) is a pattern-recognition protein that mediates antibacterial actions and innate immune responses. Its expression and role in neuroinflammatory conditions remain unclear. We observed the upregulation of PGLYRP1 in inflamed human and mouse spinal cord and brain, with microglia being the primary cellular source. Experiments using a recombinant PGLYRP1 protein show that PGLYRP1 potentiates reactive gliosis, neuroinflammation, and consequent behavioral changes in multiple animal models of neuroinflammation. Furthermore, shRNA-mediated knockdown of Pglyrp1 gene expression attenuates this inflammatory response. In addition, we identify triggering receptor expressed on myeloid cell-1 (TREM1) as an interaction partner of PGLYRP1 and demonstrate that PGLYRP1 promotes neuroinflammation through the TREM1-Syk-Erk1/2-Stat3 axis in cultured glial cells. Taken together, our results reveal a role for microglial PGLYRP1 as a neuroinflammation mediator. Finally, we propose that PGLYRP1 is a potential biomarker and therapeutic target in various neuroinflammatory diseases.


Assuntos
Microglia , Doenças Neuroinflamatórias , Animais , Camundongos , Humanos , Microglia/metabolismo , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Imunidade Inata , Inflamação/metabolismo , Citocinas/metabolismo
7.
Adv Mater ; : e2311341, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38332453

RESUMO

Use of single-atom catalysts (SACs) has become a popular strategy for tuning activity and selectivity toward specific pathways. However, conventional SAC synthesis methods require high temperatures and pressures, complicated procedures, and expensive equipment. Recently, underpotential deposition (UPD) has been investigated as a promising alternative, yielding high-loading SAC electrodes under ambient conditions and within minutes. Yet only few studies have employed UPD to synthesize SACs, and all have been limited to UPD of Cu. In this work, a flexible UPD approach for synthesis of mono- and bi-metallic Cu, Fe, Co, and Ni SACs directly on oxidized, commercially available carbon electrodes is reported. The UPD mechanism is investigated using in situ X-ray absorption spectroscopy and, finally, the catalytic performance of a UPD-synthesized Co SAC is assessed for electrochemical nitrate reduction to ammonia. The findings expand upon the usefulness and versatility of UPD for SAC synthesis, with hopes of enabling future research toward realization of fast, reliable, and fully electrified SAC synthesis processes.

8.
Medicina (Kaunas) ; 60(2)2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38399593

RESUMO

Background and Objectives: The surge in breast-related surgeries in Korea underscores the critical need for an accurate early diagnosis of silicone breast implant-related issues. Complications such as BIA-ALCL and BIA-SCC add complexity to breast health concerns, necessitating vigilant monitoring. Despite advancements, discrepancies persist between ultrasonographic and pathologic classifications of silicone implant ruptures, highlighting a need for enhanced diagnostic tools. This study explores the reliability of ultrasonography in diagnosing silicone breast implant ruptures and determining the extent of silicone migration, specifically with a focus on guiding potential capsulectomy based on pathology. Materials and Methods: A comprehensive review of medical records encompassing 5557 breast implants across 2790 patients who underwent ultrasound-assisted examinations was conducted. Among the screened implants, 8.9% (249 cases) were diagnosed with silicone breast implant rupture through ultrasonography. Subsequently, 89 women underwent revisional surgery, involving capsulectomy. The pathological analysis of 111 periprosthetic capsules from these cases aimed to assess the extent of silicone migration, and the findings were juxtaposed with the existing ultrasonographic rupture classification. Results: The diagnostic agreement between preoperative sonography and postoperative findings reached 100% for silicone breast implant ruptures. All eighty prosthetic capsules exhibiting a snowstorm sign in ultrasonography demonstrated silicone migration to capsules upon pathologic findings. Conclusions: High-resolution ultrasonography emerged as a valuable and reliable imaging modality for diagnosing silicone breast implant ruptures, with a notable ability to ascertain the extent of free silicone migration to capsules. This diagnostic precision is pivotal in informing decisions about potential capsulectomy during revisional surgery. The study advocates for an update to the current binary ultrasonographic classification, suggesting a more nuanced categorization into three types (subcapsular, intracapsular, and extracapsular) based on pathology.


Assuntos
Implantes de Mama , Feminino , Humanos , Implantes de Mama/efeitos adversos , Silicones/efeitos adversos , Sistemas Automatizados de Assistência Junto ao Leito , Reprodutibilidade dos Testes , Falha de Prótese , Ultrassonografia , Ruptura , Imageamento por Ressonância Magnética/métodos
9.
Sci Rep ; 14(1): 322, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172521

RESUMO

Citrus fruit yield is essential for market stability, as it allows businesses to plan for production and distribution. However, yield estimation is a complex and time-consuming process that often requires a large number of field samples to ensure representativeness. To address this challenge, we investigated the optimal altitude for unmanned aerial vehicle (UAV) imaging to estimate the yield of Citrus unshiu fruit. We captured images from five different altitudes (30 m, 50 m, 70 m, 90 m, and 110 m), and determined that a resolution of approximately 5 pixels/cm is necessary for reliable estimation of fruit size based on the average diameter of C. unshiu fruit (46.7 mm). Additionally, we found that histogram equalization of the images improved fruit count estimation compared to using untreated images. At the images from 30 m height, the normal image estimates fruit numbers as 73, 55, and 88. However, the histogram equalized image estimates 88, 71, 105. The actual number of fruits is 124, 88, and 141. Using a Vegetation Index such as IPCA showed a similar estimation value to histogram equalization, but I1 estimation represents a gap to actual yields. Our results provide a valuable database for future UAV field investigations of citrus fruit yield. Using flying platforms like UAVs can provide a step towards adopting this sort of model spanning ever greater regions at a cheap cost, with this system generating accurate results in this manner.


Assuntos
Citrus , Dispositivos Aéreos não Tripulados , Diagnóstico por Imagem , Frutas , Altitude
10.
Value Health ; 27(3): 313-321, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38191024

RESUMO

OBJECTIVE: This study aimed to measure the value of increasing lung cancer screening rates for high-risk individuals and its impact on health disparities. METHODS: The model estimated changes in health economic outcomes if low-dose computed tomography screening increased from current to 100% compliance, following clinical guidelines. Current low-dose computed tomography screening rates were estimated by income, education, and race, using 2017-2019 Behavioral Risk Factor Surveillance System data. The model contained a decision tree module to segment the population by screening outcomes and a Markov chain module to estimate cancer progression over time. Model parameters included information on survival, quality of life, and costs related to cancer diagnosis, treatment, and adverse events. Distributional cost-effectiveness analysis estimated the net monetary value from reduced health disparities-measured using quality-adjusted life expectancy-across income, education, and race groups. Outcomes were assessed over 30 years. RESULTS: Lung cancer screening eligibility using US Preventive Services Task Force guidelines was higher for individuals with income <$15 000 (47.2%) and without a high-school education (46.1%) than individuals with income >$50 000 (16.6%) and with a college degree (13.5%), respectively. Increasing lung cancer screening to 100% compliance was cost-effective ($64 654 per quality-adjusted life-year) and produced economic value by up to $560 per person ($182.1 billion for United States overall). Up to 32.2% of the value was due to reductions in health disparities. CONCLUSIONS: Significant value in increasing lung cancer screening rates derived from reducing health disparities. Policy makers and clinicians may not be appropriately prioritizing cancer screening if value from reducing health disparities is unconsidered.


Assuntos
Detecção Precoce de Câncer , Neoplasias Pulmonares , Humanos , Estados Unidos , Qualidade de Vida , Programas de Rastreamento , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Análise Custo-Benefício , Tomografia Computadorizada por Raios X/métodos , Iniquidades em Saúde
11.
Cancers (Basel) ; 15(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38067321

RESUMO

Prostate cancer (PCa) used to be one of the most common nondermatologic cancers in men that can be treated only with surgery. However, a revolutionary breakthrough came in the 1980s with the introduction of long-acting luteinizing hormone-releasing hormone (LHRH) agonists for the curative treatment of PCa. This paradigm shift contributed to the combined use of androgen deprivation therapy (ADT), chemotherapy, and radiotherapy for the treatment. The latest data highlight the use of treatment intensification (TI), i.e., combined use of radiotherapy (RT) and hormonal or drug treatments, for localized or locally advanced PCa. Indeed, the results of combined modality treatments have shown a reduction in disease-specific mortality and improved overall survival. Although TI seems promising, more research studies are warranted to confirm its efficacy. This review summarizes the latest available outcome results of pivotal trials and clinical studies on the efficacy of TI.

12.
J Leukoc Biol ; 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38149462

RESUMO

Lipocalin-2 (LCN2), a neutrophil gelatinase-associated lipocalin (NGAL), is a 25 kDa secreted protein implicated in a broad range of inflammatory diseases affecting the brain and periphery. It is a pleotropic protein expressed by various immune and non-immune cells throughout the body. Importantly, the surge in LCN2 levels in disease states has been associated with a myriad of undesirable effects, further exacerbating the ongoing pathological processes. In the brain, glial cells are the principal source of LCN2, which plays a definitive role in determining their functional phenotypes. In different central nervous system (CNS) pathologies, an increased expression of glial LCN2 has been linked to neurotoxicity. LCN2 mediates a crosstalk between central and peripheral immune cells under neuroinflammatory conditions. One intriguing aspect is that elevated LCN2 levels in peripheral disorders, such as cancer, metabolic conditions, and liver diseases, potentially incite an inflammatory activation of glial cells while disrupting neuronal functions. This review comprehensively summarizes the influence of LCN2 on the exacerbation of neuroinflammation by regulating various cellular processes. Additionally, this review explores LCN2 as a mediator of neuroimmune crosstalk in various CNS pathologies and highlights the role of LCN2 in carrying inflammatory signals along the neuroimmune axis.

13.
Prog Neurobiol ; 231: 102544, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37940033

RESUMO

Peripheral nerve injury disrupts the Schwann cell-axon interaction and the cellular communication between them. The peripheral nervous system has immense potential for regeneration extensively due to the innate plastic potential of Schwann cells (SCs) that allows SCs to interact with the injured axons and exert specific repair functions essential for peripheral nerve regeneration. In this study, we show that EBP50 is essential for the repair function of SCs and regeneration following nerve injury. The increased expression of EBP50 in the injured sciatic nerve of control mice suggested a significant role in regeneration. The ablation of EBP50 in mice resulted in delayed nerve repair, recovery of behavioral function, and remyelination following nerve injury. EBP50 deficiency led to deficits in SC functions, including proliferation, migration, cytoskeleton dynamics, and axon interactions. The adeno-associated virus (AAV)-mediated local expression of EBP50 improved SCs migration, functional recovery, and remyelination. ErbB2-related proteins were not differentially expressed in EBP50-deficient sciatic nerves following injury. EBP50 binds and stabilizes ErbB2 and activates the repair functions to promote regeneration. Thus, we identified EBP50 as a potent SC protein that can enhance the regeneration and functional recovery driven by NRG1-ErbB2 signaling, as well as a novel regeneration modulator capable of potential therapeutic effects.


Assuntos
Regeneração Nervosa , Traumatismos dos Nervos Periféricos , Fosfoproteínas , Células de Schwann , Trocadores de Sódio-Hidrogênio , Animais , Camundongos , Axônios/fisiologia , Regeneração Nervosa/fisiologia , Traumatismos dos Nervos Periféricos/metabolismo , Células de Schwann/metabolismo , Nervo Isquiático/lesões , Nervo Isquiático/metabolismo , Fosfoproteínas/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo
14.
Environ Sci Technol ; 57(45): 17610-17619, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37910821

RESUMO

Cleaning a fouled membrane using warm water, instead of commonly used fouling control chemicals, is an approach advocated in resource-limited settings, where small-scale membrane filtration is used to provide clean water. Thermoresponsive polymers coated onto membranes undergo a conformational change across their lower critical solution temperature (LCST), enabling foulant removal during such temperature-swing cleaning. However, their intrinsic hydrophobicity above the LCST poses a fundamental material challenge. In this study, we examine how thermoresponsive polymers can be optimally copolymerized with hydrophilic polymers by precisely manipulating monomer arrangement of thermoresponsive N-isopropylacrylamide and hydrophilic 2-[2-(2-methoxyethoxy)ethoxy]ethyl acrylate. We successfully grafted these copolymers with different monomer arrangements onto poly(ether sulfone) ultrafiltration membranes while maintaining other polymer characteristics, such as the degree of polymerization and grafting density, constant. We found that placing hydrophilic polymer blocks at the outermost surface above the thermoresponsive polymer blocks is critical to achieving high surface hydrophilicity while preserving the thermoresponsive functionality. We demonstrate enhanced fouling resistance and efficient temperature-swing cleaning with optimized copolymer design based on their interaction with bovine serum albumin during static adsorption, filtration, and cleaning processes. These findings emphasize the importance of accurately tailoring the polymer architecture to enable more efficient filtration with reduced fouling and the capability to effectively clean the fouled membrane by simply using warm water.


Assuntos
Incrustação Biológica , Polímeros , Polímeros/química , Incrustação Biológica/prevenção & controle , Interações Hidrofóbicas e Hidrofílicas , Temperatura , Água/química , Membranas Artificiais
15.
Environ Sci Technol ; 57(47): 19054-19063, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37943016

RESUMO

Peroxymonosulfate (PMS)-based electrochemical advanced oxidation processes (EAOPs) have received widespread attention in recent years, but the precise nature of PMS activation and its impact on the overall process performance remain poorly understood. This study presents the first demonstration of the critical role played by the oxygen reduction reaction in the effective utilization of PMS and the subsequent enhancement of overall pollutant remediation. We observed the concurrent generation of H2O2 via oxygen reduction during the cathodic PMS activation by a model nitrogen-doped carbon nanotube catalyst. A complex interplay between H2O2 generation and PMS activation, as well as a locally increased pH near the electrode due to the oxygen reduction reaction, resulted in a SO4•-/•OH-mixed oxidation environment that facilitated pollutant degradation. The findings of this study highlight a unique dependency between PMS-driven and H2O2-driven EAOPs and a new perspective on a previously unexplored route for further enhancing PMS-based treatment processes.


Assuntos
Poluentes Ambientais , Peróxido de Hidrogênio , Peróxidos , Oxirredução , Oxigênio
16.
Nat Commun ; 14(1): 7255, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945562

RESUMO

Ceramic membranes are a promising alternative to polymeric membranes for selective separations, given their ability to operate under harsh chemical conditions. However, current fabrication technologies fail to construct ceramic membranes suitable for selective molecular separations. Herein, we demonstrate a molecular-level design of ceramic thin-film composite membranes with tunable subnanometer pores for precise molecular sieving. Through burning off the distributed carbonaceous species of varied dimensions within hybrid aluminum oxide films, we created membranes with tunable molecular sieving. Specifically, the membranes created with methanol showed exceptional selectivity toward monovalent and divalent salts. We attribute this observed selectivity to the dehydration of the large divalent ions within the subnanometer pores. As a comparison, smaller monovalent ions can rapidly permeate with an intact hydration shell. Lastly, the flux of neutral solutes through each fabricated aluminum oxide membrane was measured for the demonstration of tunable separation capability. Overall, our work provides the scientific basis for the design of ceramic membranes with subnanometer pores for molecular sieving using atomic layer deposition.

17.
Front Cell Dev Biol ; 11: 1288373, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37954206

RESUMO

BLT2 is a low-affinity leukotriene B4 receptor that plays an essential role in the pathogenesis of various inflammatory diseases, including asthma and cancer. BLT2 is minimally expressed in a normal internal environment but is overexpressed in a stress-induced inflammatory environment. Recent research indicated that human BLT2 has two distinct forms. Although their functions are likely to be different, very few studies investigated these differences. Therefore, this paper will discuss about the two distinct forms of human BLT2; the short-form of BLT2 and the long-form of BLT2.

18.
ACS ES T Eng ; 3(10): 1504-1510, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37854075

RESUMO

Nanobubble (NB) generation of reactive oxygen species (ROS), especially hydroxyl radical (·OH), has been controversial. In this work, we extensively characterize NBs in solution, with a focus on ROS generation (as ·OH), through a number of methods including degradation of ·OH-specific target compounds, electron paramagnetic resonance (EPR), and a fluorescence-based indicator. Generated NBs exhibit consistent physical characteristics (size, surface potential, and concentration) when compared with previous studies. For conditions described, which are considered as high O2 NB concentrations, no degradation of benzoic acid (BA), a well-studied ·OH scavenger, was observed in the presence of NBs (over 24 h) and no EPR signal for ·OH was detected. While a positive fluorescence response was measured when using a fluorescence probe for ·OH, aminophenyl fluorescein (APF), we provide an alternate explanation for the result. Gas/liquid interfacial characterization indicates that the surface of a NB is proton-rich and capable of inducing acid-catalyzed hydrolysis of APF, which results in a false (positive) fluorescence response. Given these negative results, we conclude that NB-induced ·OH generation is minimal, if at all, for conditions evaluated.

19.
Eur J Med Chem ; 261: 115864, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37839347

RESUMO

Leukotriene B4 (LTB4) is a potent chemoattractant that can recruit and activate immune cells such as neutrophils, eosinophils, and monocytes to sites of inflammation. Excessive production of LTB4 has been linked to acute and chronic inflammatory diseases, including asthma, rheumatoid arthritis, and psoriasis. Inhibiting the binding of LTB4 to its receptors, BLT1 and BLT2, is a potential strategy for treating these conditions. While several BLT1 antagonists have been developed for clinical trials, most have failed due to efficacy and safety issues. Therefore, discovering selective BLT2 antagonists could improve our understanding of the distinct functions of BLT1 and BLT2 receptors and their pharmacological implications. In this study, we aimed to discover novel BLT2 antagonists by synthesizing a series of biphenyl analogues based on a BLT2 selective agonist, CAY10583. Among the synthesized compounds, 15b was found to selectively inhibit the chemotaxis of CHO-BLT2 cells with an IC50 value of 224 nM without inhibiting the chemotaxis of CHO-BLT1 cells. 15b also inhibited the binding of LTB4 and BLT2 with a Ki value of 132 nM. Furthermore, 15b had good metabolic stability in liver microsomes and moderate bioavailability (F = 34%) in in vivo PK studies. 15b also showed in vivo efficacy in a mouse model of asthma, reducing airway hyperresponsiveness by 59% and decreasing Th2 cytokines by up to 46%. Our study provides a promising lead for the development of selective BLT2 antagonists as potential therapeutics for inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease.


Assuntos
Artrite Reumatoide , Asma , Camundongos , Cricetinae , Animais , Leucotrieno B4 , Asma/tratamento farmacológico , Inflamação , Células CHO , Receptores do Leucotrieno B4/metabolismo
20.
Environ Sci Technol ; 57(36): 13681-13690, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37650677

RESUMO

Here, we investigate the stability and performance of single-atom Pd on TiO2 for the selective dechlorination of 4-chlorophenol. A challenge inherent to single atoms is their high surface free energy, which results in a tendency for the surface migration and aggregation of metal atoms. This work evaluates various factors affecting the stability of Pd single-atoms, including atomic dispersion, coordination environment, and substrate properties, under reductive aqueous conditions. The transition from single atoms to clusters vastly enhanced dechlorination kinetics without diminishing carbon-chlorine bond selectivity. X-ray absorption spectroscopy analysis using both in situ and ex situ conditions followed the dynamic transformation of single atoms into amorphous clusters, which consist of a unique unsaturated coordination environment and few nanometer diameter. The intricate relationship between stability and performance underscores the vital role of detailed characterization to properly determine the true active species for dehalogenation reactions.


Assuntos
Carbono , Paládio , Cloretos , Cloro , Cinética
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