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1.
J Chem Phys ; 160(16)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38651809

RESUMO

Chiral quantum dots (QDs) are promising materials applied in many areas, such as chiral molecular recognition and spin selective filter for charge transport, and can be prepared by facile ligand exchange approaches. However, ligand exchange leads to an increase in surface defects and reduces the efficiencies of radiative recombination and charge transport, which restricts further applications. Here, we investigate the light-induced photoluminescence (PL) enhancement in chiral L- and D-cysteine CdSe QD thin films, providing a strategy to increase the PL. The PL intensity of chiral CdSe QD films can be significantly enhanced over 100 times by continuous UV laser irradiation, indicating a strong passivation of surface defects upon laser irradiation. From the comparative measurements of the PL intensity evolutions in vacuum, dry oxygen, air, and humid nitrogen atmospheres, we conclude that the mechanism of PL enhancement is photo-induced surface passivation with the assistance of water molecules.

2.
Nat Commun ; 15(1): 815, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280849

RESUMO

Radiative cooling is a zero-energy technology that enables subambient cooling by emitting heat into outer space (~3 K) through the atmospheric transparent windows. However, existing designs typically focus only on the main atmospheric transparent window (8-13 µm) and ignore another window (16-25 µm), under-exploiting their cooling potential. Here, we show a dual-selective radiative cooling design based on a scalable thermal emitter, which exhibits selective emission in both atmospheric transparent windows and reflection in the remaining mid-infrared and solar wavebands. As a result, the dual-selective thermal emitter exhibits an ultrahigh subambient cooling capacity (~9 °C) under strong sunlight, surpassing existing typical thermal emitters (≥3 °C cooler) and commercial counterparts (as building materials). Furthermore, the dual-selective sample also exhibits high weather resistance and color compatibility, indicating a high practicality. This work provides a scalable and practical radiative cooling design for sustainable thermal management.

3.
Materials (Basel) ; 17(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38255627

RESUMO

The advanced science and technology of polymer matrix nanomaterials are rapidly developing fields that focus on the synthesis, characterization, and application of nanomaterials in polymer matrices [...].

4.
ACS Appl Bio Mater ; 7(1): 104-113, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38149377

RESUMO

The pursuit of environmentally friendly and highly effective antifouling materials for marine applications is of paramount importance. In this study, we successfully synthesized novel rare earth-based complexes by coordinating cerium (Ce III), samarium (Sm III), and europium (Eu III) with pyrithione (1-hydroxy-2-pyridinethione; PT). Extensive characterizations were performed, including single-crystal X-ray analysis, which revealed the intriguing binuclear structure of these complexes. This structural motif comprises two rare-earth ions intricately double-bridged by two oxygen atoms from the PT ligand, resulting in a distinctive and intriguing geometry. Furthermore, the central rare earth ion is surrounded by three sulfur atoms and two additional oxygen atoms, forming a unique distorted bicapped trigonal prismatic configuration. Compared with conventional antifouling biocides such as sodium pyrithione (NaPT), copper pyrithione (CuPT), and zinc pyrithione (ZnPT), these newly synthesized rare-earth complexes exhibited a remarkable boost in their in vitro antibacterial efficacy against both Gram-positive and Gram-negative bacteria. Additionally, these complexes demonstrated significant potential as antialgal agents, displaying impressive activity against marine planktonic organisms. These findings underscore the promising application prospects of these rare-earth complexes in the field of marine antifouling.


Assuntos
Antibacterianos , Bactérias Gram-Negativas , Piridinas , Tionas , Antibacterianos/farmacologia , Bactérias Gram-Positivas , Oxigênio
6.
J Anaesthesiol Clin Pharmacol ; 39(3): 385-391, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025551

RESUMO

Background and Aims: Glucocorticoids are commonly utilised as adjuvants to enhance nerve block quality and prolong the analgesic duration. Its systemic effects, after a single-injection adductor canal block (ACB) followed by a continuous infusion, are unclear. The aim of the study was to assess the systemic effects of a single dose of dexamethasone sodium phosphate (DEX), or a combination of DEX and methylprednisolone acetate (MPA), on fasting blood glucose (FBG) and white blood cell count (WBC) when administered perineurally via ACB. Material and Methods: A single-center retrospective study on total knee arthroplasty (TKA) was performed and a total of 95 patients were included in the final analysis. Patients were divided into three groups based on adjuvants received in ACB: Control group (N = 41) and two treatment groups, DEX group (N = 33) and DEX/MPA group (N = 21). Our primary outcomes were the change of FBG from its preoperative baseline value on postoperative day (POD) 2. The secondary outcomes included change of FBG on POD 0 and POD 1, and change of WBC on POD 0, POD 1, and POD 2. Results: The FBG change from baseline in the DEX group was significantly higher than that in the control group (difference = 14.04, 95% CI: 1.3 to 26.77), P = 0.031) on POD 0. The WBC change from baseline in the DEX/MPA group was statistically significant higher than control on POD 0 (2.62 (1.52 to 3.37), P < 0.0001). No significant differences between DEX and DEX/MPA group were found on any given postoperative days for FBG and WBC. Conclusion: This study provided preliminary safety data on the use of a combination of glucocorticoids with hydrophilic (DEX) and lipophilic (MPA) properties as local anesthetic adjuvants in ACB, which induced similar levels of changes on FBG and WBC as those from both control and DEX alone group.

7.
J Pain Res ; 16: 3807-3835, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38026463

RESUMO

Introduction: With the current surge on peripheral nerve blocks in post-cesarean pain management and the historical lack of unequivocal evidence supporting its universal use, this review intended to re-examine the extended scope of literature on regional anesthesia and postoperative analgesia in low-transverse cesarean section. Methods: A literature search was conducted up to April 2023 using PubMed to identify articles relevant to our search words "cesarean section", "neuraxial morphine", "post-cesarean analgesia", as well as the name of each individual nerve block. The literature search was ultimately narrowed to systematic reviews and randomized controlled trials published between 2012 and 2023. We define, describe, and discuss the evidence surrounding each individual regional anesthetic technique in the presence and absence of intrathecal morphine, which is used as the gold standard when appropriate. Results: In the absence of neuraxial morphine, all regional anesthetic techniques have some level of analgesic benefit in the post-cesarean analgesia. Transversus Abdominis Plane blocks continue to have the most studies in their use. Newer fascia plane blocks including the anterior Quadratus Lumborum, and Erector Spinae Plane blocks provide significant analgesia. In addition, direct comparison among peripheral nerve blocks consistently favors the more proximal, centralized techniques. Conversely, in the presence of neuraxial morphine, no peripheral anesthetic technique has reliably and reproducibly demonstrated an added analgesic benefit regardless of the peripheral nerve block technique or location of local anesthetic injection in the post-cesarean population. Conclusion: Neuraxial morphine continues to be the gold standard for post-cesarean section analgesia, the benefit of additional single injection regional anesthetic is currently not evidence supported. In cases where neuraxial opioids have not or cannot be given, there is overwhelming evidence that regional anesthetic techniques improve post-cesarean section analgesia and decrease post-operative opioid consumption. Even though there is no consensus on the optimal peripheral nerve block, emerging evidence suggests more centralized abdominal fascia plane block trends towards better analgesia.

8.
Chem Biol Drug Des ; 102(6): 1618-1631, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37705133

RESUMO

The advancement of colorectal cancer (CRC) prevention, detection, and treatment is essential to ensure that survivors live longer and higher-quality lives. The field of cancer detection and therapy has undergone a revolution with the development of nanotechnology for targeted drug delivery. The significant problems with the delivery of cancer drugs are their solubility, stability, and nonspecific distribution. There is a challenge that the acidic and enzymatic environment in the digestive tract will modify or destroy the medication or the active pharmaceutical ingredient. To overcome the problems, nanoparticles have been widely employed during the past several years to increase the specificity, selectivity, and controlled release of drug delivery systems. The site-specific and targeted delivery leads to reduce toxicity and side effects. With respect to the capability and utilization of cyclodextrin-based nanoparticles in different aspects of the tumour microenvironment and gut microbiota, a survey of current research papers was conducted via looking through databases including GoogleScholar, PubMed, Web of Science, and Scopus. This review aims to summarize cutting-edge nanoparticulate-based technologies and therapies for CRC.


Assuntos
Antineoplásicos , Neoplasias Colorretais , Ciclodextrinas , Nanopartículas , Humanos , Sistemas de Liberação de Medicamentos/métodos , Antineoplásicos/uso terapêutico , Preparações Farmacêuticas , Neoplasias Colorretais/tratamento farmacológico , Microambiente Tumoral
9.
Molecules ; 28(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570750

RESUMO

Matrine is a quinoline alkaloid extracted and separated from the dried root, fruit, and other parts of the plant Sophora flavescens using an organic solvent. Matrine exhibits a variety of biological activities and is widely used in pharmacy, agronomy, and other fields. Due to its low bioavailability, poor chemical stability, and toxicity to the central nervous system, a large number of researchers have searched for matrine derivatives with higher biological activity and safety by modifying its structure. In this review article, the research progress of matrine derivatives obtained using two methods (extraction from Sophora flavescens and structural modifications) from 2018 to 2022 in terms of pharmacological activity, mechanism of action, and structure-activity relationship are presented. The modification of matrine over the past five years has been mainly on the D-ring. Many new matrine alkaloids have been extracted from natural products, some of which have good pharmacological activity, which broadens the strategy for matrine structural modification in the future.


Assuntos
Produtos Biológicos , Matrinas , Sophora flavescens , Matrinas/síntese química , Matrinas/química , Matrinas/isolamento & purificação , Matrinas/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Sophora flavescens/química , Raízes de Plantas/química , Frutas/química , Relação Estrutura-Atividade , Humanos , Animais , Linhagem Celular
10.
Sci Bull (Beijing) ; 68(18): 2054-2062, 2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37599177

RESUMO

Due to the huge energy consumption of traditional cooling- and heating-based electricity, passive radiative cooling and solar heating with a minimum carbon footprint using the outer space and Sun as natural thermodynamic resources have attracted much attention. However, most passive devices are static and monofunctional, and cannot meet the practical requirements of dynamic cooling and heating under various conditions. Here, we demonstrate a smart thermal-gated (STG) bilayer membrane that enables fully automatic and temperature-adaptive radiative cooling and solar heating. Specifically, this device can switch from reflective to absorptive (white to black) in the solar wavelength with the reduction in optical scattering upon ambient temperature, corresponding to a sunlight reflectivity change from 0.962 to 0.059 when the temperature drops below ∼30 °C, whereas its mid-infrared emissivity remains at ∼0.95. Consequently, this STG membrane achieves a temperature of ∼5 °C below ambient (a key signature of radiative cooling) under direct sunlight (peak solar irradiance >900 W m-2) in summer and a solar heating power of ∼550 W m-2 in winter. Theoretical analysis reveals the substantial advantage of this switchable cooling/heating device in potential energy saving compared with cooling-only and heating-only strategies when widely used in different climates. It is expected that this work will pave a new pathway for designing temperature-adaptive devices with zero energy consumption and provide an innovative way to achieve sustainable energy.

11.
Materials (Basel) ; 16(16)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37629842

RESUMO

Polymer matrix nanomaterials have revolutionized materials science due to their unique properties resulting from the incorporation of nanoscale fillers into polymer matrices [...].

12.
Sensors (Basel) ; 23(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37448017

RESUMO

A field dynamic balancer is crucial to the applications of magnetically suspended turbomolecular pumps. Therefore, this paper presents a novel field dynamic balancing method based on autocentering control mode without any additional instrumentation. Firstly, the dynamics of the active magnetic bearing rotor system with unbalance are modeled. Through model analysis, it was found that making the rotor rotate around the geometric axis can improve the accuracy of dynamic balancing. Secondly, the relationship between the correcting masses and the synchronous currents based on the influence coefficient method is established. Then, an autocentering controller is designed to make the rotor rotate around the geometric axis. The synchronous currents can be detected and extracted by the current transducers to calculate the unbalance correction mass. Finally, the experimental results show that this novel field dynamic balancing method can effectively eliminate the majority of rotor unbalance. Compared with the original unbalance of a rotor, the synchronous current in the A-end has been reduced by 71.4% and the synchronous current in the B-end, by 90.8% with the proposed method.


Assuntos
Coração Auxiliar , Magnetismo
13.
Clin Drug Investig ; 43(6): 435-445, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37326942

RESUMO

BACKGROUND AND OBJECTIVE: There is an unmet need for a safer anticoagulant since bleeding remains a concern with currently approved anticoagulants. Coagulation factor XI (FXI) is an attractive anticoagulant drug target with limited a role in physiological hemostasis. The objective of this study was to evaluate the safety, pharmacokinetics, and pharmacodynamics of SHR2285, a novel small molecule FXIa inhibitor, in healthy Chinese volunteers. METHODS: The study consisted of single ascending doses part (part 1: 25-600 mg) and multiple ascending doses part (part 2: 100, 200, 300, and 400 mg). In both parts, subjects were randomized in a 3:1 ratio to receive SHR2285 or placebo orally. Blood, urine and feces samples were collected to describe its pharmacokinetic and pharmacodynamic profile. RESULTS: In total, 103 healthy volunteers completed the study. SHR2285 was well tolerated. SHR2285 was absorbed rapidly with median time to maximum plasma concentration (Tmax) of 1.50 to 3.00 h. The geometric median half-life (t1/2) of SHR2285 varied from 8.74 to 12.1 h across 25-600 mg single dose. Total systemic exposure of metabolite SHR164471 was approximately 1.77- to 3.61-fold that of the parent drug. The plasma concentration of SHR2285 and SHR164471 reached steady state by the morning of Day 7, with low accumulation ratio (0.956-1.20 and 1.18-1.56, respectively). The increase in pharmacokinetic exposure of SHR2285 and SHR164471 was less than dose proportional. Food has minimal effect on the pharmacokinetics of SHR2285 and SHR164471. SHR2285 produced an exposure-dependent prolongation of activated partial thromboplastin time (APTT) and a decrease in FXI activity. The maximum FXI activity inhibition rate (geometric mean) at steady state was 73.27%, 85.58%, 87.77% and 86.27% for 100-400 mg, respectively. CONCLUSIONS: SHR2285 was generally safe and well tolerated in healthy subjects across a wide range of doses. SHR2285 exhibited a predictable pharmacokinetic profile and an exposure-related pharmacodynamic profile. CLINICALTRIALS: gov Identifier NCT04472819; registered on July 15, 2020.


Assuntos
Anticoagulantes , População do Leste Asiático , Fator XIa , Humanos , Administração Oral , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacocinética , Anticoagulantes/farmacologia , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fator XIa/antagonistas & inibidores , Voluntários Saudáveis
14.
Cureus ; 15(5): e39503, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37366446

RESUMO

Pain control after total hip arthroplasty is associated with patient satisfaction, early discharge, and improved surgical outcomes. Two commonly utilized opioid-reducing analgesic modalities are periarticular injection (PAI) by surgeons and motor-sparing peripheral nerve block (PNB) by anesthesiologists. We present a case contrasting PAI and PNB in a single patient undergoing bilateral total hip arthroplasty. For the left hip, the patient received preoperative transmuscular quadratus lumborum, femoral nerve, and lateral femoral cutaneous nerve blocks using a combination of low-concentration local anesthetic and glucocorticoids. For the right hip, the patient received an intraoperative PAI with liposomal bupivacaine. The patient's pain scores and recovery were evaluated for three months postoperatively. The patient's pain scores on postoperative day (POD) zero to five were consistently lower in the left hip than in the right hip. For this patient undergoing bilateral hip replacement, preoperative PNBs were superior to PAI for postoperative pain control.

16.
Talanta ; 259: 124520, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37058943

RESUMO

Glutathione (GSH) is present in almost every cell in the body and plays various integral roles in many biological processes. The Golgi apparatus is a eukaryotic organelle for the biosynthesis, intracellular distribution, and secretion of various macromolecules; however, the mechanism of GSH in the Golgi apparatus has not been fully elucidated. Here, specific and sensitive sulfur-nitrogen co-doped carbon dots (SNCDs) with orange-red fluorescence was synthesized for the detection of GSH in the Golgi apparatus. The SNCDs have a Stokes shift of 147 nm and excellent fluorescence stability, and they exhibited excellent selectivity and high sensitivity to GSH. The linear response of the SNCDs to GSH was in the range of 10-460 µM (LOD = 0.25 µΜ). More importantly, we used SNCDs with excellent optical properties and low cytotoxicity as probes, and successfully realized golgi imaging in HeLa cells and GSH detection at the same time.


Assuntos
Corantes Fluorescentes , Pontos Quânticos , Humanos , Células HeLa , Corantes Fluorescentes/toxicidade , Pontos Quânticos/toxicidade , Carbono/toxicidade , Glutationa , Complexo de Golgi , Nitrogênio , Limite de Detecção
17.
Medicine (Baltimore) ; 102(9): e32940, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36862892

RESUMO

BACKGROUND: Carpal tunnel syndrome (CTS) is more common in people who need to engage in repetitive wrist work. Once it has occurred, localized pain and numbness of the fingers will develop, in severe cases, muscle atrophy will even arise, and after rest and physical therapy, many patients will still be unable to relieve or recur. In this case, the patient can receive intrathecal glucocorticoid injections, but the hormone injections alone can only provide short-term relief, and because the mechanical factors of median nerve compression are not fundamentally removed. Therefore, combined acupotomy release can help to release the compression of the transverse carpal ligament on the nerve and increase the volume within the carpal tunnel to achieve more satisfactory long-term results. Hence, a meta-analysis is necessary to provide evidence whether there is a significant difference in the treatment of CTS with acupotomy release combined with glucocorticoid intrathecal injection (ARGI) compared with isolated glucocorticoid intrathecal injection (GI). METHODS: We will search, with no time restriction, without any restriction of language and status, the time from the establishment of the database to October 2022, on the following databases: PubMed, Cochrane central register of controlled trials, Web of Science, Chinese national knowledge infrastructure, Wanfang data, Chinese scientific journals database, Chinese databases SinoMed, and electronic databases. The electronic database search will be supplemented by a manual search of the reference lists of included articles. We will apply the risk-of-bias tool of the Cochrane collaboration for randomized controlled trials to assess the methodological quality. Risk-of-Bias Assessment Tool for nonrandomized studies was used to evaluate the quality of comparative studies. Statistical analysis will be conducted using RevMan 5.4 software. RESULTS: This systematic review will evaluate the difference in efficacy of ARGI versus isolated GI in the treatment of CTS. CONCLUSION: The conclusion of this study will provide evidence for judging whether ARGI is superior to GI for treatment of CTS.


Assuntos
Terapia por Acupuntura , Síndrome do Túnel Carpal , Humanos , Síndrome do Túnel Carpal/terapia , Glucocorticoides , Extremidade Superior , Punho , Revisões Sistemáticas como Assunto , Metanálise como Assunto
18.
J Pain Res ; 16: 635-648, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891457

RESUMO

Acute compartment syndrome (ACS) is a devastating complication that can happen in almost every part of the human body, most noticeably after long bone fractures. The cardinal symptom of ACS is pain in excess of what would otherwise be expected from the underlying injury and unresponsive to routine analgesia treatment. There is paucity of literature on major analgesic management strategies including opioid analgesia, epidural anesthesia, and peripheral nerve blocks with regard to their differential efficacy and safety of pain management in patients at risk of developing ACS. The lack of quality data has led to recommendations that are perhaps more conservative than they should be, particularly when it comes to peripheral nerve blocks. In this review article, we attempt to make recommendations in favor of regional anesthesia in this vulnerable group of patients and strategies that will optimize adequate pain control and improve surgical outcome without jeopardizing patient safety.

19.
Sci Rep ; 13(1): 2894, 2023 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-36807376

RESUMO

To investigate the potential mechanism of resveratrol in anti-fatigue by network pharmacology and molecular docking, and to investigate the anti-fatigue efficacy of resveratrol through in vitro animal experiments. Resveratrol action targets and fatigue-related targets were obtained using various databases. The anti-fatigue targets of resveratrol were obtained using the Venn diagram, uploaded to the String database, imported into Cytoscape 3.7.1, and constructed into a Protein-protein interaction network. The target genes were then subjected to Gene ontology and Kyoto encyclopedia of gene and genome enrichment analysis. Molecular docking verification was performed on the binding ability of the core target to resveratrol. Using swimming-trained mice as exercise models, exhaustive swimming time and fatigue-related biochemical parameters were used as indicators to investigate the effects of resveratrol on exercise endurance and energy metabolism. 104 anti-fatigue targets and 10 core target genes of resveratrol were obtained. KEGG analysis enrichment included AGE-RAGE signaling pathway in diabetic complications, Human cytomegalovirus infection, and Pathways in cancer. Molecular docking showed that the core target genes TP53, PIK3R1, AKT1, PIK3CA, and MAPK1 had good binding activity to resveratrol. Animal experiments showed that resveratrol could prolong the exhaustive swimming time of endurance-trained mice (P < 0.01), decrease aspartate aminotransferase, alanine aminotransferase, uric acid, blood lactate (P < 0.01), decrease blood urea nitrogen (P < 0.05), increase the liver glycogen, muscle glycogen (P < 0.01). Conclusion: Resveratrol has the characteristics of multiple targets and multiple pathways in anti-fatigue; resveratrol can enhance exercise endurance in mice.


Assuntos
Medicamentos de Ervas Chinesas , Farmacologia em Rede , Humanos , Animais , Camundongos , Simulação de Acoplamento Molecular , Resveratrol , Genes Reguladores , Mapas de Interação de Proteínas , Medicina Tradicional Chinesa
20.
Polymers (Basel) ; 15(3)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36771938

RESUMO

Flax fibers are widely used as the strongest natural fibers in composite parts with advanced structures. Due to their excellent mechanical properties and recyclability, they have attracted more attention from the aviation and automotive industries, etc. These composite parts are usually obtained by preforming reinforcements or prepregs at high temperatures, and their mechanical behaviors are greatly affected by temperature variations. To improve the understanding of the mechanical properties of flax fiber materials, especially for the braided fabric with non-orthogonal structures, uniaxial tensile tests at different temperatures and tensile speeds were conducted on hollow tubular braided fabrics. The thermomechanical properties of Flax/Polyamide12 (PA12) prepregs were analyzed. The results show that temperature and tensile speed have obvious effects on the strength and shear stiffness of tubular fabrics. The strength and shear stiffness of the fabric decreases as the ambient temperature increases. Meanwhile, the strength of the fabric can also be improved by appropriately increasing the tensile speed. In addition, according to the experimental results, a theoretical model is established to describe the shear angle on the smallest circumference of the fabric, which provides a theoretical basis for the subsequent simulation process. The test results can provide a reference for the manufacture of flax fiber-reinforced composites with tubular structures.

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