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INTRODUCTION: Although statin therapy reduces cardiovascular events, statin use is associated with the risk of new-onset diabetes mellitus (NODM). Using a linked dataset, we evaluated the effect of statin treatment on vascular outcomes and NODM development in patients with ischemic stroke. METHODS: From the dataset, we identified 20,250 patients with acute ischemic stroke who had neither a prior history of DM nor a previous history of statin use before the index stroke. Patients were divided into statin users and non-users. The outcomes were NODM and vascular outcomes, including recurrent ischemic stroke and acute myocardial infarction (AMI). RESULTS: Of the 20,250 patients, 13,706 (67.7%) received statin treatment after the index stroke. For the risk of NODM, a time-response relationship was observed between the use of statins and NODM; a longer post-stroke follow-up duration substantially increased the risk of NODM. Among those with ischemic stroke exceeding 3 years, statin users had an approximately 1.7-fold greater risk of NODM than statin non-users. Statin therapy significantly reduced the risk of recurrent ischemic stroke by 54% (HR 0.46, 95% CI, 0.43-0.50, P < 0.001) across all stroke subtypes. CONCLUSION: Statin therapy following ischemic stroke increased the occurrence of NODM in patients over a period of 3 years. Despite the increased risk of NODM, statin therapy shows a beneficial effect in reducing major cardiovascular events such as recurrent ischemic stroke and AMI in patients with ischemic stroke.
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Marine organisms, such as sea urchins like Heliocidaris crassispina, produce bioactive substances with antimicrobial activity to protect themselves from the high density of microorganisms in their habitats. One such substance, Echinochrome A (Ech A), has been isolated from various sea urchins' shells and spines using strong acidic solutions and organic solvents. Ech A, however, has not been reported from the coelomic fluid of H. crassispina. In this study, we report the antimicrobial activity of H. crassispina coelomic fluid extract against various microbes, evaluating its potential for purifying potent antimicrobial materials. Upon confirming the extract as a promising source of antimicrobial materials, we isolated antimicrobial compounds from the extract. A series of HPLC steps were taken to purify antimicrobial materials from the H. crassispina coelomic fluid extract, resulting in the isolation of two single absorbance peaks showing antimicrobial activity against Staphylococcus aureus. One peak consisted of a single antimicrobial compound with a molecular weight (MW) corresponding to Ech A, while the other peak comprised five MWs inferred to be those of Ech A and its oxidative products. The elution of Ech A in two separate peaks may be attributable to the presence of Ech A's isomer, as reported in several previous studies. The use of the environmentally friendly extraction method in procurement of Ech A from the coelomic fluid would contribute to the implementation of risk-reducing extraction method for researchers studying Ech A from sea urchins.
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Staphylococcus aureus , Animais , Staphylococcus aureus/efeitos dos fármacos , Anthocidaris/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Ouriços-do-Mar/química , Cromatografia Líquida de Alta Pressão , Antibacterianos/farmacologia , Antibacterianos/química , NaftoquinonasRESUMO
OBJECTIVE: To develop an individualized method for detecting cognitive adverse events (CAEs) in the context of an ongoing trial of electroconvulsive therapy for refractory agitation and aggression for advanced dementia (ECT-AD study). METHODS: Literature search aimed at identifying (a) cognitive measures appropriate for patients with advanced dementia, (b) functional scales to use as a proxy for cognitive status in patients with floor effects on baseline cognitive testing, and (c) statistical approaches for defining a CAE, to develop CAEs monitoring plan specifically for the ECT-AD study. RESULTS: Using the Severe Impairment Battery-8 (SIB-8), baseline floor effects are defined as a score of ≤5/16. For patients without floor effects, a decline of ≥6 points is considered a CAE. For patients with floor effects, a decline of ≥30 points from baseline on the Barthel Index is considered a CAE. These values were derived using the standard deviation index (SDI) approach to measuring reliable change. CONCLUSIONS: The proposed plan accounts for practical and statistical challenges in detecting CAEs in patients with advanced dementia. While this protocol was developed in the context of the ECT-AD study, the general approach can potentially be applied to other interventional neuropsychiatric studies that carry the risk of CAEs in patients with advanced dementia.
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Doença de Alzheimer , Demência , Eletroconvulsoterapia , Humanos , Comportamento Motor Aberrante na Demência , Cognição , Demência/complicações , Demência/terapia , Demência/psicologia , Eletroconvulsoterapia/efeitos adversos , Eletroconvulsoterapia/métodos , Eletroconvulsoterapia/psicologia , Agitação Psicomotora/etiologia , Agitação Psicomotora/terapia , Estudos Clínicos como AssuntoRESUMO
INTRODUCTION: Diesel particulate matter (DPM) emitted from diesel engines is a major source of air pollutants. DPM is composed of elemental carbon, which adsorbs organic compounds including toxic polycyclic aromatic hydrocarbons (PAHs). The skin, as well as airways, is directly exposed to DPM, and association of atopic dermatitis, psoriasis flares, and premature skin aging with air pollutant levels has been documented. In skin, the permeation of DPM and DPM-adsorbed compounds is primarily blocked by the epidermal permeability barrier deployed in the stratum corneum. Depending upon the integrity of this barrier, certain amounts of DPM and DPM-adsorbed compounds can permeate into the skin. However, this permeation into human skin has not been completely elucidated. METHODS: We assessed the permeation of PAHs (adsorbed to DPM) into skin using ex vivo normal (barrier-competent) organ-cultured human skin after application of DPM. Two major PAHs, 2-methylnaphthalene and triphenylene, and a carcinogenic PAH, benzo(a)pyrene, all found in DPM, were measured in the epidermis and dermis using liquid chromatography electrospray ionization tandem mass spectrometry. In addition, we investigated whether a topical formulation can attenuate the permeation of DPM into skin. RESULTS: 2-Methylnaphthalene, triphenylene, and benzo(a)pyrene were recovered from the epidermis. Although these PAHs were also detected in the dermis after DPM application, these PAH levels were significantly lower than those found in the epidermis. We also demonstrated that a topical formulation that has the ability to form more uniform membrane structures can significantly suppress the permeation of PAHs adsorbed to DPM into the skin. CONCLUSION: Toxic compounds adsorbed by DPM can permeate even barrier-competent skin. Hence, barrier-compromised skin, such as in atopic dermatitis, psoriasis, and xerosis, is even more vulnerable to air pollutants. A properly formulated topical mixture that forms certain membrane structures on the skin surface can effectively prevent permeation of exogenous substances, including DPM, into skin.
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BACKGROUND: Open-top light-sheet microscopy (OT-LSM) is a specialized microscopic technique for the high-throughput cellular imaging of optically cleared, large-sized specimens, such as the brain. Despite the development of various OT-LSM techniques, achieving submicron resolution in all dimensions remains. RESULTS: We developed a high-resolution open-top axially swept LSM (HR-OTAS-LSM) for high-throughput and high-resolution imaging in all dimensions. High axial and lateral resolutions were achieved by using an aberration-corrected axially swept excitation light sheet in the illumination arm and a high numerical aperture (NA) immersion objective lens in the imaging arm, respectively. The high-resolution, high-throughput visualization of neuronal networks in mouse brain and retina specimens validated the performance of HR-OTAS-LSM. CONCLUSIONS: The proposed HR-OTAS-LSM method represents a significant advancement in the high-resolution mapping of cellular networks in biological systems such as the brain and retina.
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Encéfalo , Neurônios , Camundongos , Animais , Microscopia de Fluorescência/métodosRESUMO
BACKGROUND: A growing volume of research suggests that religion protects against late-life suicide, but it remains unclear whether effects are relevant to clinical samples, which facets of religion are most relevant, and variations over the course of mood disorders (e.g. during periods of euthymia, depression, and/or heightened suicidality). METHOD: Eighty adults aged 55-85 years with mood disorders completed assessments of religion (affiliation, service attendance, importance of religion, belief and faith in God), depression, and suicidality over time (M = 7.31 measurements over M = 727 days). We computed metrics to identify mean and maximum levels of depression and suicidality, and the number of episodes of significant depression and suicidality experienced by each participant. RESULTS: Religious affiliation and importance of religion, but not service attendance, belief, or faith in God, were associated with lower mean and maximum depression. Conversely, all facets of religion predicted significantly lower mean and maximum levels of suicidality (rs ranging from -0.24 to -0.39), and substantially less likelihood of experiencing significant suicidality during the study (ORs ranging from 0.19 to 0.33). Service attendance, belief, and faith in God predicted less suicidality even among individuals who did not affiliate with a religious group. CONCLUSIONS: Religious factors, particularly faith in God, are associated with substantially less suicidality over time among older adults with mood disorders, irrespective of religious affiliation.
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Transtornos do Humor , Suicídio , Humanos , Idoso , Religião , Ideação Suicida , Espiritualidade , Religião e PsicologiaRESUMO
Membrane-enveloped viruses are responsible for most viral pandemics in history, and more effort is needed to advance broadly applicable countermeasures to mitigate the impact of future outbreaks. In this Perspective, we discuss how biosensing techniques associated with lipid model membrane platforms are contributing to improving our mechanistic knowledge of membrane fusion and destabilization that is closely linked to viral entry as well as vaccine and antiviral drug development. A key benefit of these platforms is the simplicity of interpreting the results which can be complemented by other techniques to decipher more complicated biological observations and evaluate the biophysical functionalities that can be correlated to biological activities. Then, we introduce exciting application examples of membrane-targeting antivirals that have been refined over time and will continue to improve based on biophysical insights. Two ways to abrogate the function of viral membranes are introduced here: (1) selective disruption of the viral membrane structure and (2) alteration of the membrane component. While both methods are suitable for broadly useful antivirals, the latter also has the potential to produce an inactivated vaccine. Collectively, we emphasize how biosensing tools based on membrane interfacial science can provide valuable information that could be translated into biomedicines and improve their selectivity and performance.
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Antivirais , Internalização do Vírus , Antivirais/farmacologia , Membranas/química , Desenvolvimento de Vacinas , Lipídeos/análiseRESUMO
BACKGROUND: Autobiographical memory (AM) is valuable not only as an indicator of mental health and cognitive function, but also as a target of therapeutic intervention for older adults. In the context of the COVID-19 pandemic, the demand for online psychosocial interventions and assessment services has sharply increased. Thus, the present study examined the effectiveness of videoconferencing AM (vAM) intervention using the Ecological Momentary Assessment (EMA) method in addition to the traditional paper-and-pencil assessment among samples of community dwelling older adults. METHODS: Twenty-seven older adults (aged 66-86 years) participated in a vAM intervention composed of 4 weekly 90-min sessions. The primary outcome was AM specificity, with secondary outcomes as depressive symptom and cognitive function, measured before and after the intervention. In addition, daily emotions were measured through EMA over 4 weeks of intervention. The EMA data were analyzed using a multilevel analysis. RESULTS: The results showed low dropout rates (7%) and high EMA response rates (85%). Autobiographical memory specificity increased (Cohen's d = 0.678), and the level of depression declined significantly (Cohen's d = 0.375) after the program. Additionally, measures assessing cognitive function, such as Seoul Verbal Learning Test and DSC (Digit Symbol Coding), showed significant improvements. The EMA results indicated a decrease in the intensity and proportion of negative emotions experienced during the program. CONCLUSIONS: This study is the first to utilize videoconferencing and EMA to deliver an AM intervention targeting older adults. The intervention was effective in improving mental health and cognitive function, including AM in older adults. Additionally, EMA was found to be a feasible tool for use in older adults.
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COVID-19 , Memória Episódica , Humanos , Idoso , Pandemias , Cognição , Saúde MentalRESUMO
INTRODUCTION: The outermost layer of the skin, the epidermis, is directly exposed to external stress (e.g., irradiation, allergens, and chemicals). Changes in epidermal conditions/environment in response to this stress could also influence conditions of the dermis, located directly beneath the epidermis. Yet, whether/how any epidermal environment changes in response to external stress affect dermal functions has not been completely clarified. METHODS: We employed ultraviolet irradiation B (UVB) (which hardly reaches the dermis) as a model of external stress. Human keratinocytes and human dermal fibroblasts were treated with UVB and conditioned medium of keratinocytes exposed to UVB (UVB-keratinocyte-M), respectively. We assessed (1) inflammatory cytokines and lipid mediators in keratinocytes; (2) matrix metalloprotease (MMP) levels and collagen degradation in fibroblasts; (3) ex vivo organ-cultured human skin was treated with UVB. MMP levels and collagen degradation were examined; (4) test whether the mixture of agent (agent cocktail) consisting of dihydroceramide, niacin amide, resveratrol, glucosyl hesperidin, and phytosterol ester that has been shown to improve skin barrier integrity can mitigate influence of UVB in skin; and (5) a pilot one-arm human clinical test to assess efficacy of formulation containing agent cocktail on stratum corneum hydration, skin elasticity, and wrinkle index. RESULTS: Inflammatory-cytokine and -lipid mediator production were increased in cultured keratinocytes treated with UVB, while matrix MMP-1, -3, and -9 production and collagen degradation were increased in fibroblasts incubated with UVB-keratinocyte-M. mRNA expression of COL1A1 (that codes type 1 collagen) levels was decreased in fibroblasts incubated with UVB-keratinocyte-M. The study using ex vivo organ-cultured human skin showed both MMP-1 and MMP-9 expression were increased in both epidermis and dermis and increased dermal collagen degradation following UVB irradiation. Increased MMP production and collagen degradation were attenuated by application of an agent cocktail. Finally, a pilot clinical study demonstrated that the formulation containing our agent cocktail likely has the ability to improve skin hydration, increase skin elasticity, and reduce the appearance of wrinkles. CONCLUSION: Epidermal changes in epidermal environment and conditions in response to external stress affect dermal conditions, and these negative effects of external stress on various skin layers can be pharmacologically mitigated.
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Metaloproteinase 1 da Matriz , Envelhecimento da Pele , Humanos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Derme/metabolismo , Epiderme/metabolismo , Colágeno Tipo I , Citocinas/metabolismo , Lipídeos , Raios Ultravioleta , FibroblastosRESUMO
BACKGROUND: Optimal antiplatelet strategy for patients with ischemic stroke who were already on single antiplatelet therapy (SAPT) remains to be elucidated. This study aimed to evaluate the effect of different antiplatelet regimens on vascular and safety outcomes at 1 year after non-cardioembolic stroke in patients previously on SAPT. METHODS: We identified 9,284 patients with acute non-cardioembolic ischemic stroke that occurred on SAPT using linked data. Patients were categorized into three groups according to antiplatelet strategy at discharge: 1) SAPT; 2) dual antiplatelet therapy (DAPT); and 3) triple antiplatelet therapy (TAPT). One-year outcomes included recurrent ischemic stroke, composite outcomes (recurrent ischemic stroke, myocardial infarction, intracerebral hemorrhage, and death), and major bleeding. RESULTS: Of 9,284 patients, 5,565 (59.9%) maintained SAPT, 3,638 (39.2%) were treated with DAPT, and 81 (0.9%) were treated with TAPT. Multiple antiplatelet therapy did not reduce the risks of 1-year recurrent stroke (DAPT, hazard ratio [HR], 1.08, 95% confidence interval [CI], 0.92-1.27, P = 0.339; TAPT, HR, 0.71, 95% CI, 0.27-1.91, P = 0.500) and 1-year composite outcome (DAPT, HR, 1.09, 95% CI, 0.68-1.97, P = 0.592; TAPT, HR, 1.46, 95% CI, 0.68-1.97, P = 0.592). However, the TAPT groups showed an increased risk of major bleeding complications (DAPT, HR, 1.23, 95% CI, 0.89-1.71, P = 0.208; TAPT, HR, 4.65, 95% CI, 2.01-10.74, P < 0.001). CONCLUSION: Additional use of antiplatelet agents in patients with non-cardioembolic ischemic stroke who were already on SAPT did not reduce the 1-year incidence of vascular outcomes, although it increased the risk of bleeding complications.
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AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Big Data , Web Semântica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controleRESUMO
Antimicrobial fatty acids derived from natural sources and renewable feedstocks are promising surface-active substances with a wide range of applications. Their ability to target bacterial membrane in multiple mechanisms offers a promising antimicrobial approach for combating bacterial infections and preventing the development of drug-resistant strains, and it provides a sustainable strategy that aligns with growing environmental awareness compared to their synthetic counterparts. However, the interaction and destabilization of bacterial cell membranes by these amphiphilic compounds are not yet fully understood. Here, we investigated the concentration-dependent and time-dependent membrane interaction between long-chain unsaturated fatty acids-linolenic acid (LNA, C18:3), linoleic (LLA, C18:2), and oleic acid (OA, C18:1)-and the supported lipid bilayers (SLBs) using quartz crystal microbalance-dissipation (QCM-D) and fluorescence microscopy. We first determined the critical micelle concentration (CMC) of each compound using a fluorescence spectrophotometer and monitored the membrane interaction in real time following fatty acid treatment, whereby all micellar fatty acids elicited membrane-active behavior primarily above their respective CMC values. Specifically, LNA and LLA, which have higher degrees of unsaturation and CMC values of 160 µM and 60 µM, respectively, caused significant changes in the membrane with net |Δf| shifts of 23.2 ± 0.8 Hz and 21.4 ± 0.6 Hz and ΔD shifts of 5.2 ± 0.5 × 10-6 and 7.4 ± 0.5 × 10-6. On the other hand, OA, with the lowest unsaturation degree and CMC value of 20 µM, produced relatively less membrane change with a net |Δf| shift of 14.6 ± 2.2 Hz and ΔD shift of 8.8 ± 0.2 × 10-6. Both LNA and LLA required higher concentrations than OA to initiate membrane remodeling as their CMC values increased with the degree of unsaturation. Upon incubating with fluorescence-labeled model membranes, the fatty acids induced tubular morphological changes at concentrations above CMC. Taken together, our findings highlight the critical role of self-aggregation properties and the degree of unsaturated bonds in unsaturated long-chain fatty acids upon modulating membrane destabilization, suggesting potential applications in developing sustainable and effective antimicrobial strategies.
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Anti-Infecciosos , Micelas , Ácidos Graxos , Bicamadas Lipídicas/química , Anti-Infecciosos/farmacologia , Ácido OleicoRESUMO
Skin cancer is one of the most prevalent cancers in the Caucasian population. In the United States, it is estimated that at least one in five people will develop skin cancer in their lifetime, leading to significant morbidity and a healthcare burden. Skin cancer mainly arises from cells in the epidermal layer of the skin, where oxygen is scarce. There are three main types of skin cancer: malignant melanoma, basal cell carcinoma, and squamous cell carcinoma. Accumulating evidence has revealed a critical role for hypoxia in the development and progression of these dermatologic malignancies. In this review, we discuss the role of hypoxia in treating and reconstructing skin cancers. We will summarize the molecular basis of hypoxia signaling pathways in relation to the major genetic variations of skin cancer.
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Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutâneas , Humanos , Estados Unidos , Neoplasias Cutâneas/patologia , Melanoma/metabolismo , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , HipóxiaRESUMO
Doxorubicin (DOX), an anthracycline-based chemotherapeutic agent, is widely used to treat various types of cancer; however, prolonged treatment induces cardiomyotoxicity. Although studies have been performed to overcome DOX-induced cardiotoxicity (DICT), no effective method is currently available. This study investigated the effects and potential mechanisms of Poncirus trifoliata aqueous extract (PTA) in DICT. Changes in cell survival were assessed in H9c2 rat cardiomyocytes and MDA-MB-231 human breast cancer cells. The C57BL/6 mice were treated with DOX to induce DICT in vivo, and alterations in electrophysiological characteristics, serum biomarkers, and histological features were examined. The PTA treatment inhibited DOX-induced decrease in H9c2 cell viability but did not affect the MDA-MB-231 cell viability. Additionally, the PTA restored the abnormal heart rate, R-R interval, QT interval, and ST segment and inhibited the decrease in serum cardiac and hepatic toxicity indicators in the DICT model. Moreover, the PTA administration protected against myocardial fibrosis and apoptosis in the heart tissue of mice with DICT. PTA treatment restored DOX-induced decrease in the expression of NAD(P)H dehydrogenase quinone acceptor oxidoreductase 1 in a PTA concentration-dependent manner. In conclusion, the PTA inhibitory effect on DICT is attributable to its antioxidant properties, suggesting the potential of PTA as a phytotherapeutic agent for DICT.
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Miócitos Cardíacos , Poncirus , Ratos , Camundongos , Humanos , Animais , NAD/metabolismo , Poncirus/metabolismo , Regulação para Cima , Estresse Oxidativo , Camundongos Endogâmicos C57BL , Doxorrubicina/toxicidade , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/etiologia , Cardiotoxicidade/prevenção & controle , Oxirredutases/metabolismo , Quinonas/farmacologiaRESUMO
The rapid growth in the global human population has increased the prevalence of emerging infectious diseases, which poses a major risk to public health. In search of effective clinical solutions, the acquisition of knowledge and understanding of biomolecular processes associated with viral pathogens represents a prerequisite. In this context, biophysical engineering approaches are particularly promising since they can resolve biomolecular interactions systematically by circumventing the complexities associated with experiments involving natural biological systems. The engineering approaches encompass the design and construction of biomimetic platforms that simulate the physiological system. This approach enables us to characterize, measure, and quantitatively analyze biomolecular interactions.In this Account, we summarize biophysical measurements that our group has successfully adopted to develop broad-spectrum antiviral drugs based on the lipid envelope antiviral disruption (LEAD) strategy, targeting the structural integrity of the outer viral membrane to abrogate viral infectivity. We particularly focus on the engineering aspects related to the design and construction of the tethered lipid vesicle platform, which closely mimics the viral membrane. We first outline the development of the LEAD agents screening platform that integrates soft matter design components with biomaterials and surface functionalization strategies to facilitate parallel measurements tracking peptide-induced destabilization of nanoscale, virus-mimicking vesicles with tunable size and composition. Then, we describe how this platform can be effectively employed to gain insights into the membrane curvature dependency of certain peptides. The fundamental knowledge acquired through this systematic process is crucial in the identification and subsequent development of antiviral drug candidates. In particular, we highlight the development of curvature-sensitive α-helical (AH) peptides as a broad-spectrum antiviral agent that has been demonstrated as an effective therapeutic treatment against multiple enveloped viruses. Also, we introduce a tethered cluster of vesicles to mimic clusters of enveloped viruses, exhibiting higher infectivity levels in the biological system. Then, we discuss key considerations, including experimental artifacts, namely dye leakage and imaging-related photobleaching, and corresponding corrective measures to improve the accuracy of quantitative interpretation. With the ongoing development and application of the tethered lipid vesicle platform, there is a compelling opportunity to explore fundamental biointerfacial science and develop a new class of broad-spectrum antiviral agents to prepare for the future membrane-enveloped viral pandemics.
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Antivirais/síntese química , Biomimética , Desenvolvimento de Medicamentos , Antivirais/química , Antivirais/farmacologia , Fenômenos Biofísicos , Vírus/química , Vírus/efeitos dos fármacosRESUMO
Bidirectional vesicle transport along microtubules is necessary for cell viability and function, particularly in neurons. When multiple motors are attached to a vesicle, the distance a vesicle travels before dissociating is determined by the race between detachment of the bound motors and attachment of the unbound motors. Motor detachment rate constants (koff) can be measured via single-molecule experiments, but motor reattachment rate constants (kon) are generally unknown, as they involve diffusion through the bilayer, geometrical considerations of the motor tether length, and the intrinsic microtubule binding rate of the motor. To understand the attachment dynamics of motors bound to fluid lipid bilayers, we quantified the microtubule accumulation rate of fluorescently labeled kinesin-1 motors in a 2-dimensional (2D) system where motors were linked to a supported lipid bilayer. From the first-order accumulation rate at varying motor densities, we extrapolated a koff that matched single-molecule measurements and measured a 2D kon for membrane-bound kinesin-1 motors binding to the microtubule. This kon is consistent with kinesin-1 being able to reach roughly 20 tubulin subunits when attaching to a microtubule. By incorporating cholesterol to reduce membrane diffusivity, we demonstrate that this kon is not limited by the motor diffusion rate, but instead is determined by the intrinsic motor binding rate. For intracellular vesicle trafficking, this 2D kon predicts that long-range transport of 100-nm-diameter vesicles requires 35 kinesin-1 motors, suggesting that teamwork between different motor classes and motor clustering may play significant roles in long-range vesicle transport.
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There has been enormous interest in understanding and utilizing plasmon-enhanced fluorescence (PEF) with metal nanostructures, but maximizing the enhancement in a reproducible, quantitative manner while reliably controlling the distance between dyes and metal particle surface for practical applications is highly challenging. Here, we designed and synthesized fluorescence-amplified nanocuboids (FANCs) with highly enhanced and controlled PEF signals, and fluorescent silica shell-coated FANCs (FS-FANCs) were then formed to fixate the dye position and increase particle stability and fluorescence signal intensity for biosensing applications. By uniformly modifying fluorescently labeled DNA on Au nanorods and forming ultraflat Ag shells on them, we were able to reliably control the distance between fluorophores and Ag surface and obtained an â¼186 fluorescence enhancement factor with these FANCs. Importantly, FS-FANCs were utilized as fluorescent nanoparticle tags for microarray-based miRNA detection, and we achieved >103-fold higher sensitivity than commercially available chemical fluorophores with 100 aM to 1 pM dynamic range.
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MicroRNAs , DNA , Corantes Fluorescentes , Dióxido de Silício , Espectrometria de FluorescênciaRESUMO
OBJECTIVES: The neutrophil-to-lymphocyte ratio (NLR) is a known marker of systemic inflammation. Recent studies demonstrated its applicability as a marker of poor prognosis for stroke patients. In this study, we evaluated the relationship between dynamic changes in the NLR and sICH in patients with successful recanalization following ERT. MATERIALS AND METHODS: This study included 128 patients with acute ischemic stroke who underwent successful ERT between January 2013 and November 2019. We evaluated the NLR pre-ERT (at admission) and post-ERT (at 24-36 h after ERT). The symptomatic ICH and miserable outcomes at 3 months after ERT were analyzed as outcomes. sICH was defined as type-2 parenchymal hematoma with neurological deterioration (defined as National Institute of Health Stroke Scale score ≥4). Moreover, a modified Rankin Scale score of 5-6 at 3 months was considered a miserable outcome. RESULTS: Among the included patients, sICH occurred in 12 (9.4%). The sICH group had significantly higher post-ERT NLR (P < 0.001) and ∆NLR (calculated as the difference between pre-ERT NLR and post-ERT NLR) (P = 0.004). In the multivariate analysis, the post-ERT NLR was independently associated with sICH (odds ratio [OR], 1.166; 95% confidence interval [CI], 1.041-1.306; P = 0.008) and miserable outcome at 3 months (OR, 1.101; 95% CI, 1.002-1.210; P = 0.045). CONCLUSIONS: This study demonstrated that temporal elevation of the NLR is associated with sICH events after successful ERT in patients with acute ischemic stroke. The temporal variation in NLR may help to identify high-risk patients with sICH after ERT.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/terapia , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Humanos , Linfócitos , Neutrófilos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Resultado do TratamentoRESUMO
Background and Objectives: Flexibility is one of the most important physical fitness parameters in the geriatric population. Brachial-ankle pulse wave velocity (baPWV) is a measure of systemic arterial stiffness. However, data on the association between flexibility and arterial stiffness in the older adult population are limited. Therefore, we aim to investigate this association by using the sit-and-reach test (SRT) and measuring baPWV. Materials and Methods: We reviewed data from the 2014-2015 Korean Institute of Sports Science Fitness Standards Project. Individuals older than 65 years with SRT and baPWV data were included. A generalized linear regression analysis was conducted to assess the association between flexibility and arterial stiffness. Multiple relevant confounding factors were adjusted. Results: A total of 615 individuals were included in the analysis. The mean age of the male and female participants was 71.44 ± 4.42 and 70.64 ± 4.13 years, respectively. The mean SRT result was 6.58 ± 9.97 and 18.04 ± 7.48 cm, respectively. After multivariable adjustment among the male participants, the higher SRT result tertiles were inversely associated with baPWV (ß (95% confidence interval): 3.11-11.00 cm, -74.45 (-140.93, -8.55); ≥11.01 cm, -108.17 (-177.65, -38.70)) in comparison with the lowest tertile. The female participants did not show any significant correlation between the SRT result and baPWV. Conclusions: Our results suggest an inverse association between trunk flexibility and systemic arterial stiffness, expressed as the SRT result and baPWV, respectively, in older Korean men but no association in older Korean women. Sex differences might influence the association between flexibility and arterial stiffness in the older adult population.
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Rigidez Vascular , Idoso , Índice Tornozelo-Braço , Artéria Braquial , Feminino , Humanos , Masculino , Análise de Onda de Pulso , Fatores de RiscoRESUMO
The identification of each cell type is essential for understanding multicellular communities. Antibodies set as biomarkers have been the main toolbox for cell-type recognition, and chemical probes are emerging surrogates. Herein we report the first small-molecule probe, CDgB, to discriminate B lymphocytes from T lymphocytes, which was previously impossible without the help of antibodies. Through the study of the origin of cell specificity, we discovered an unexpected novel mechanism of membrane-oriented live-cell distinction. B cells maintain higher flexibility in their cell membrane than T cells and accumulate the lipid-like probe CDgB more preferably. Because B and T cells share common ancestors, we tracked the cell membrane changes of the progenitor cells and disclosed the dynamic reorganization of the membrane properties over the lymphocyte differentiation progress. This study casts an orthogonal strategy for the small-molecule cell identifier and enriches the toolbox for live-cell distinction from complex cell communities.
Assuntos
Linfócitos B/citologia , Membrana Celular/metabolismo , Corantes Fluorescentes/química , Linfócitos T/citologia , Animais , Linfócitos B/química , Linfócitos B/imunologia , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular , Membrana Celular/química , Citometria de Fluxo , Lipidômica , Camundongos , Linfócitos T/química , Linfócitos T/imunologiaRESUMO
The irreversible formation of cholesterol monohydrate crystals within biological membranes is the leading cause of various diseases, including atherosclerosis. Understanding the process of cholesterol crystallization is fundamentally important and could also lead to the development of improved therapeutic strategies. This has driven several studies investigating the effect of the environmental parameters on the induction of cholesterol crystallite growth and the structure of the cholesterol crystallites, while the kinetics and mechanistic aspects of the crystallite formation process within lipid membranes remain poorly understood. Herein, we fabricated cholesterol crystallites within a supported lipid bilayer (SLB) by adsorbing a cholesterol-rich bicellar mixture onto a glass and silica surface and investigated the real-time kinetics of cholesterol crystallite nucleation and growth using epifluorescence microscopy and quartz crystal microbalance with dissipation (QCM-D) monitoring. Microscopic imaging showed the evolution of the morphology of cholesterol crystallites from nanorod- and plate-shaped habits during the initial stage to mostly large, micron-sized three-dimensional (3D) plate-shaped crystallites in the end, which was likened to Ostwald ripening. QCM-D kinetics revealed unique signal responses during the later stage of the growth process, characterized by simultaneous positive frequency shifts, nonmonotonous energy dissipation shifts, and significant overtone dependence. Based on the optically observed changes in crystallite morphology, we discussed the physical background of these unique QCM-D signal responses and the mechanistic aspects of Ostwald ripening in this system. Together, our findings revealed mechanistic details of the cholesterol crystallite growth kinetics, which may be useful in biointerfacial sensing and bioanalytical applications.