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1.
J Anesth ; 33(3): 463-477, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31076946

RESUMO

Over the last decade, considerable progress has been made regarding infraclavicular brachial plexus block (ICB) in adults, especially since the introduction of ultrasound guidance. The advancements in ICB have been attributed to the development of various approaches to improve the success rate and reduce complications. This has also necessitated a unified nomenclature system to facilitate comparison among different approaches. This review aimed to propose an anatomical nomenclature system by classifying ICB approaches into proximal and distal ones to aid future research and provide practice advisories according to recent updates. We also comprehensively discuss various aspects of this nomenclature system. Our review suggests that ultrasound-guided ICB should be categorized as an advanced technique that should be performed under supervision and dual guidance. For one-shot block, the conventional distal approach is still preferred but should be modified to follow ergonomic practice, with the arm in the proper position. For continuous ICB, the proximal approach is promising for reducing local anesthetic volume and increasing efficacy. Nevertheless, further studies are warranted in this direction. We provide practice advisories to maximize safety and minimize adverse events, and recommend designing future studies on ICB according to these findings based on the unified nomenclature system.


Assuntos
Anestésicos Locais/administração & dosagem , Bloqueio do Plexo Braquial/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Humanos
2.
Phys Rev Lett ; 120(8): 085702, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29543024

RESUMO

First-order interfacial phaselike transformations that break the mirror symmetry of the symmetric ∑5 (210) tilt grain boundary (GB) are discovered by combining a modified genetic algorithm with hybrid Monte Carlo and molecular dynamics simulations. Density functional theory calculations confirm this prediction. This first-order coupled structural and adsorption transformation, which produces two variants of asymmetric bilayers, vanishes at an interfacial critical point. A GB complexion (phase) diagram is constructed via semigrand canonical ensemble atomistic simulations for the first time.

3.
Appl Opt ; 55(4): 873-8, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26836094

RESUMO

A theoretical analysis of the thermal effects of a circular bimorph piezoelectric actuator (CBPA) was performed. The circular bimorph structure consists of two flexible piezoelectric ceramic layers and one metallic layer in the middle, and is powered to produce flexural deformation. The CBPA, which may be a good match for large adaptive optics telescopes, has a large stroke and a high resonance frequency. We have derived analytical solutions (both the static solution and the dynamic solution) of the thermal effects of introducing (and increasing the thickness of) a metallic layer into the bimorph. Numerical results are presented to illustrate the dependence of the CBPA's performance upon the physical parameters.


Assuntos
Eletricidade , Modelos Teóricos , Óptica e Fotônica/instrumentação , Temperatura , Análise de Elementos Finitos , Análise Numérica Assistida por Computador
4.
J Med Educ Curric Dev ; 11: 23821205241283804, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39314826

RESUMO

GASMAN software, a simulation tool for inhalational anesthetics' pharmacokinetics and pharmacodynamics, has become essential in both anesthesia education and clinical practice. This review explores its applications, highlighting its effectiveness in enhancing medical education and its impact on clinical anesthesia management. In educational settings, GASMAN software facilitates a deeper understanding of anesthetic pharmacology through interactive and visual simulations, thereby improving students' learning outcomes and engagement. Clinically, it aids anesthesiologists in optimizing anesthetic dosing, enhancing patient safety, and supporting real-time decision-making during surgeries. Despite its advantages, GASMAN software faces limitations such as the absence of physiological feedback and the need for continuous data model updates. Future directions include technical enhancements, integration with advanced patient simulators, and broader dissemination through educational partnerships. This review emphasizes the significant contributions of GASMAN software to anesthesia education and clinical practice and suggests pathways for future improvements and wider adoption.

5.
Ibrain ; 10(2): 197-216, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38915944

RESUMO

This review comprehensively assesses the epidemiology, interaction, and impact on patient outcomes of perioperative sleep disorders (SD) and perioperative neurocognitive disorders (PND) in the elderly. The incidence of SD and PND during the perioperative period in older adults is alarmingly high, with SD significantly contributing to the occurrence of postoperative delirium. However, the clinical evidence linking SD to PND remains insufficient, despite substantial preclinical data. Therefore, this study focuses on the underlying mechanisms between SD and PND, underscoring that potential mechanisms driving SD-induced PND include uncontrolled central nervous inflammation, blood-brain barrier disruption, circadian rhythm disturbances, glial cell dysfunction, neuronal and synaptic abnormalities, impaired central metabolic waste clearance, gut microbiome dysbiosis, hippocampal oxidative stress, and altered brain network connectivity. Additionally, the review also evaluates the effectiveness of various sleep interventions, both pharmacological and nonpharmacological, in mitigating PND. Strategies such as earplugs, eye masks, restoring circadian rhythms, physical exercise, noninvasive brain stimulation, dexmedetomidine, and melatonin receptor agonists have shown efficacy in reducing PND incidence. The impact of other sleep-improvement drugs (e.g., orexin receptor antagonists) and methods (e.g., cognitive-behavioral therapy for insomnia) on PND is still unclear. However, certain drugs used for treating SD (e.g., antidepressants and first-generation antihistamines) may potentially aggravate PND. By providing valuable insights and references, this review aimed to enhance the understanding and management of PND in older adults based on SD.

6.
RSC Med Chem ; 14(6): 1049-1059, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37360387

RESUMO

In recent decades, natural products from marine organisms have been widely studied for the treatment of various breast cancers. Among them, polysaccharides have been favored by researchers because of their good effects and safety. In this review, polysaccharides from marine algae including macroalgae and microalgae, chitosan, microorganisms such as marine bacteria and fungi, and starfish are addressed. Their anticancer activities on different breast cancers and action mechanisms are discussed in detail. In general, polysaccharides from marine organisms are potential sources of low side-effect and high efficiency anticancer drugs for development. However, further research on animals and clinical research are needed.

7.
J Food Biochem ; 46(3): e13927, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34595763

RESUMO

Polysaccharides extracted from Asian traditional food source have been demonstrated to possess different antitumor activities mostly without side effect. In this paper, we reviewed many kinds of polysaccharides from different Asian food source and their antitumor activities. Some are common food such as different mushroom with more research. Some are special e.g., Ginseng,Salvia,Astragalus,Lycium barbarum etc. with relatively fewer research. This review mainly focused on their structure, derivatives, antitumor activities and their mechanism of action in the last decades. It aimed to bridge traditional Asian ingredients with tumor and cancer curation in order to avoid side effect of traditional treatment. PRACTICAL APPLICATIONS: There are abundant resources of Asian food. And polysaccharides from these resources have been showed good antitumor activities and immunopotentiating activity. This review introduced the advance of the polysaccharides and their antitumor activities, which will promote the development antitumor medicine derived from Asian food source, or their applications as Adjuvant therapy of traditional chemotherapy and radiotherapy. Due to their multiple antitumor activities, enhancing immunity potential, and non-toxic side-effects, it might be utilized for the treatment of multiple tumors and improve the health and the life quality of patients whether as anti-tumor drugs or as adjuvant therapy method. Furthermore, traditional Asian food source is rich. In the near future, more and more efficient polysaccharides with antitumor activities of Asian food source will be discovered. There will be broad application market for the polysaccharides.


Assuntos
Agaricales , Antineoplásicos , Medicamentos de Ervas Chinesas , Lycium , Neoplasias , Antineoplásicos/farmacologia , Medicamentos de Ervas Chinesas/química , Humanos , Lycium/química , Neoplasias/tratamento farmacológico , Polissacarídeos/química , Polissacarídeos/farmacologia
8.
PeerJ ; 7: e6409, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809437

RESUMO

Microalgae, eukaryotic unicellular plants, are increasing in demand due to their use as nutraceutical and food supplements. They consisted different kinds of biologically active components such as polysaccharides. On the other hand, cancer is the leading cause of death globally. At present, there is no efficient method to cure it. Therefore, in this work, we extracted polysaccharides from Phaeodactylum tricornutum (PTP), characterized the chemical composition and structure, and investigated its anticancer activity on HepG2 cells. The results showed that PTP was a sulfated polysaccharide with a high Mw of 4,810 kDa, and xylose, fucose, glucose and galactose were the main monosaccharides. PTP has significant anticancer activity in a dose-dependent manner (up to 60.37% at 250 ug/mL) according to MTT assays. Furthermore, cycle analysis was carried out to explain its anticancer activity. The results showed that it exhibited anticancer effect mainly through the induction of apoptosis without affecting the cycle and mitosis of HepG2 cells. This might make it a potential drug for anticancer treatment in the future.

9.
Onco Targets Ther ; 11: 6177-6187, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30288053

RESUMO

PURPOSE: Melanoma, which is initiated from melanocytes, is the most fatal type of skin cancer. Melanoma-initiating cells significantly contribute to the initiation, metastasis, and recurrence of melanoma, and CD20 is a marker of melanoma-initiating cells. All-trans retinoic acid (ATRA) has been demonstrated to induce differentiation, inhibit proliferation, and promote the apoptosis of cancer cells and cancer-initiating cells (CICs). However, there has been no report on ATRA activity against melanoma-initiating cells. In this study, we examined the activity of ATRA against melanoma-initiating cells and developed ATRA-encapsulated poly(lactic-co-glycolic acid) (PLGA) nanoparticles, which were conjugated with a CD20 antibody (ATRA-PNP-CD20) for targeted delivery of ATRA to CD20+ melanoma-initiating cells. MATERIALS AND METHODS: The effects of ATRA and ATRA-PNP-CD20 against melanoma-initiating cells were investigated using a cytotoxicity assay, tumorsphere formation assay, and flow cytometry. RESULTS: ATRA-PNP-CD20 had a size of 126.9 nm and a negative zeta potential. The drug-loading capacity of ATRA-PNP-CD20 was 8.7%, and ATRA-PNP-CD20 displayed a sustained release of ATRA for 144 hours. The results showed that ATRA-PNP-CD20 could effectively and specifically deliver ATRA to CD20+ melanoma-initiating cells, achieving superior inhibitory effects against CD20+ melanoma-initiating cells compared with those of free ATRA and nontargeted nanoparticles. To the best of our knowledge, we report for the first time a potent activity of ATRA against CD20+ melanoma-initiating cells, targeted drug delivery of ATRA via nanoparticles to melanoma-initiating cells, and the achievement of a superior inhibitory effect against melanoma-initiating cells by using a CD20 antibody. CONCLUSION: ATRA-PNP-CD20 represents a promising tool for eliminating melanoma-initiating cells and shows a potential for the therapy of melanoma.

10.
Nat Commun ; 9(1): 2764, 2018 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-30018369

RESUMO

Minor impurities can cause catastrophic fracture of normally ductile metals. Here, a classic example is represented by the sulfur embrittlement of nickel, whose atomic-level mechanism has puzzled researchers for nearly a century. In this study, coupled aberration-corrected electron microscopy and semi-grand-canonical-ensemble atomistic simulation reveal, unexpectedly, the universal formation of amorphous-like and bilayer-like facets at the same general grain boundaries. Challenging the traditional view, the orientation of the lower-Miller-index grain surface, instead of the misorientation, dictates the interfacial structure. We also find partial bipolar structural orders in both amorphous-like and bilayer-like complexions (a.k.a. thermodynamically two-dimensional interfacial phases), which cause brittle intergranular fracture. Such bipolar, yet largely disordered, complexions can exist in and affect the properties of various other materials. Beyond the embrittlement mechanism, this study provides deeper insight to better understand abnormal grain growth in sulfur-doped Ni, and generally enriches our fundamental understanding of performance-limiting and more disordered interfaces.

11.
Colloids Surf B Biointerfaces ; 151: 119-127, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-27988472

RESUMO

The clinical usage of docetaxel (DTX) has been blocked in the clinic because of its poor solubility and tumour multi-drug resistance (MDR). The dominating mechanism of MDR is the over-expression of p-gp on tumour cells. Traditional nano-medicines, such as nanoparticles and micelles, have been used to physically entrap DTX to improve their solubility, while the drug loading content was very low and the tumour resistance was neglected. In this study, the synthesized reduction-sensitive mPEG-PLGA-SS-DTX conjugate was utilized to load the p-gp inhibitor veraparmil (VRP) to prepare DTX and VRP co-delivered mPEG-PLGA-SS-DTX/VRP (PP-SS-DTX/VRP) multi-functional micelles to reverse MDR and enhance the anti-tumour effect of DTX. The micelles had a high drug loading content and showed an obvious reduction-sensitive release property for both DTX and VRP. In addition, an in vitro anti-tumour assay revealed that the micelles markedly inhibited the efflux activity of p-gp and accelerated cell apoptosis, resulting in the improvement of anti-tumour activity and reversal of MDR. The PP-SS-DTX micelles markedly enhanced the in vivo circulation time and increased the drug accumulation in tumour tissues. Therefore, the PP-SS-DTX/VRP micelle is a desirable drug delivery system for multi-drug resistance therapy of DTX and is very promising for clinical usage.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Poliésteres/química , Polietilenoglicóis/química , Succinimidas/química , Taxoides/administração & dosagem , Taxoides/química , Verapamil/administração & dosagem , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Animais , Apoptose , Neoplasias da Mama/genética , Sobrevivência Celular , Docetaxel , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Concentração Inibidora 50 , Células MCF-7 , Micelas , Microscopia Eletrônica de Transmissão , Ratos , Ratos Wistar , Solubilidade , Verapamil/química
12.
Biomed Res Int ; 2017: 8284363, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29226150

RESUMO

PURPOSE OF REVIEW: Transversus abdominis plane (TAP) block is a regional technique for analgesia of the anterolateral abdominal wall. This review highlights the nomenclature system and recent advances in TAP block techniques and proposes directions for future research. RECENT FINDINGS: Ultrasound guidance is now considered the gold standard in TAP blocks. It is easy to acquire ultrasound images; it can be used in many surgeries involving the anterolateral abdominal wall. However, the efficacy of ultrasound-guided TAP blocks is not consistent, which might be due to the use of different approaches. The choice of technique influences the involved area and block duration. To investigate the actual analgesic effects of TAP blocks, we unified the nomenclature system and clarified the definition of each technique. Although a single-shot TAP block is limited in duration, it is still the candidate of the analgesic standard for abdominal wall surgery because the use of the catheter technique and liposomal bupivacaine may overcome this limitation. SUMMARY: Ultrasound-guided TAP blocks are commonly used. With the unified nomenclature and the development of catheter technique and/or liposomal local anesthetics, TAP blocks can be applied more appropriately to achieve better pain control.


Assuntos
Músculos Abdominais/efeitos dos fármacos , Bloqueio Nervoso/métodos , Parede Abdominal , Analgesia/métodos , Anestésicos Locais/administração & dosagem , Anestésicos Locais/química , Bupivacaína/administração & dosagem , Bupivacaína/química , Humanos , Lipossomos/administração & dosagem , Lipossomos/química , Manejo da Dor/métodos , Ultrassonografia de Intervenção/métodos
13.
Int J Pharm ; 515(1-2): 281-292, 2016 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-27746331

RESUMO

The main cause of multidrug resistance (MDR) is overexpression of active efflux transporters, such as P-glycoprotein (P-gp). To reverse MDR and improve the chemotherapy effect of paclitaxel (PTX), we propose a new drug delivery system based on mixed micelles constructed with d-α-tocopheryl poly(ethylene glycol) 1000 succinate (TPGS) and the mPEG-SS-PTX conjugate with consideration that TPGS is a P-gp inhibitor that can block the cancer cell action of pumping drugs outside of cells and can enhance the anticancer effect. mPEG-SS-PTX is synthesized by conjugating hydrophilic mPEG with a hydrophobic drug, PTX, via a redox-sensitive disulfide bond. The mPEG-SS-PTX conjugate is amphiphilic and can self-assemble in water. Mixed micelles formed by the mPEG-SS-PTX conjugate and TPGS have a low critical micelle concentration (CMC, ∼1.05×10-3mg/mL) and high drug loading content (∼19.6%). The disulfide bond in the mPEG-SS-PTX conjugate can be broken in cancer cells (a reductive environment) and release PTX to kill cancer cells. In vitro cytotoxicity and cell uptake suggest that mixed micelles can effectively improve the accumulation of PTX in multidrug-resistant MCF-7 cells. Therefore, the present as-prepared mixed micelles very effectively reverse the MDR and enhance the therapeutic effect.


Assuntos
Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Etilenoglicóis/química , Oxirredução/efeitos dos fármacos , Paclitaxel/farmacologia , Vitamina E/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Humanos , Células MCF-7 , Micelas , Paclitaxel/química
14.
J Mech Behav Biomed Mater ; 53: 200-209, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26327454

RESUMO

Nacre has attracted widespread interest because its unique hierarchical structure, which is assembled by 95 wt% brittle aragonite and 5 wt% soft organic materials, leads to several orders of improvement in fracture toughness. Apart from the well proposed toughening mechanisms such as mineral bridges and tablets interlocks, the organic materials including biopolymers between tablets and proteins exist within a tablet can also potentially improve the toughness. In this work, we employ a novel approach combining steered molecular dynamics (SMD) and classical molecular dynamics (MD) to build a model of mineral-protein composite to mimic nacre tablet. The critical role of protein in improving the fracture toughness of nacre is investigated for the first time. MD simulations of single crystalline aragonite, polycrystalline aragonite and mineral-protein composite under uniaxial tensile loading are performed, and the obtained constitutive responses are compared with experimental measurements of nacre under tension. It is shown that the fracture toughness of mineral-protein composite is significantly larger than that of single crystalline or polycrystalline aragonite. Detailed atomic configuration analyses reveal that the fracture of individual computer model is governed by its unique failure mechanisms. Dislocation motion and phase transformation are observed during the failure of single crystalline aragonite. Polycrystalline aragonite fails by the inter-granular cleavage, as well as phase transformation within grain. It is surprisingly noted that other than the stretching of protein chains on grain boundaries, intra-granular fracture is triggered in mineral-protein composites. Proteins serve as strong glue between the inorganic nanograins. It is believed that the strong electrostatic interaction between protein and aragonite nanograins, combined with the remarkable plastic ductility of protein lead to the intra-granular failure, which consequently enhance the fracture toughness of the whole specimen.


Assuntos
Biomimética/métodos , Dureza , Nácar , Nanotecnologia/métodos , Carbonato de Cálcio/química , Simulação de Dinâmica Molecular , Conformação Proteica , Proteínas/química , Estresse Mecânico
15.
Proc Math Phys Eng Sci ; 471(2175): 20140758, 2015 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-25792957

RESUMO

In this paper, we present the development of a concurrent atomistic-continuum (CAC) methodology for simulation of the grain boundary (GB) structures and their interaction with other defects in ionic materials. Simulation results show that the CAC simulation allows a smooth passage of cracks through the atomistic-continuum interface without the need for additional constitutive rules or special numerical treatment; both the atomic-scale structures and the energies of the four different [001] tilt GBs in bi-crystal strontium titanate obtained by CAC compare well with those obtained by existing experiments and density function theory calculations. Although 98.4% of the degrees of freedom of the simulated atomistic system have been eliminated in a coarsely meshed finite-element region, the CAC results, including the stress-strain responses, the GB-crack interaction mechanisms and the effect of the interaction on the fracture strength, are comparable with that of all-atom molecular dynamics simulation results. In addition, CAC simulation results show that the GB-crack interaction has a significant effect on the fracture behaviour of bi-crystal strontium titanate; not only the misorientation angle but also the atomic-level details of the GB structure influence the effect of the GB on impeding crack propagation.

16.
Biomed Res Int ; 2015: 612352, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25945340

RESUMO

Sulfated polysaccharides (GSP) were isolated from the cloned Grateloupia filicina which was cultured in Jiaozhou Bay, Qingdao, China. The yield of GSP was 15.75%. The total sugar and sulfate were 40.90 and 19.89%, respectively. And the average molecular weight was 11.7 KDa. The results of neutral sugar analysis showed that GSP was mainly sulfated polysaccharides of galactose. The experiments for activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) anticoagulant assays in vitro indicated that GSP was a good potential anticoagulant. Therefore, this study supplied new thought for the cloned Grateloupia filicina exploitation of high-value products.


Assuntos
Anticoagulantes/farmacologia , Galactose/farmacologia , Polissacarídeos/farmacologia , Rodófitas/química , Anticoagulantes/química , Anticoagulantes/isolamento & purificação , Testes de Coagulação Sanguínea , China , Galactose/química , Galactose/isolamento & purificação , Humanos , Tempo de Tromboplastina Parcial , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Tempo de Protrombina , Sulfatos/química , Tempo de Trombina
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