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Many oncogenic insults deregulate RNA splicing, often leading to hypersensitivity of tumors to spliceosome-targeted therapies (STTs). However, the mechanisms by which STTs selectively kill cancers remain largely unknown. Herein, we discover that mis-spliced RNA itself is a molecular trigger for tumor killing through viral mimicry. In MYC-driven triple-negative breast cancer, STTs cause widespread cytoplasmic accumulation of mis-spliced mRNAs, many of which form double-stranded structures. Double-stranded RNA (dsRNA)-binding proteins recognize these endogenous dsRNAs, triggering antiviral signaling and extrinsic apoptosis. In immune-competent models of breast cancer, STTs cause tumor cell-intrinsic antiviral signaling, downstream adaptive immune signaling, and tumor cell death. Furthermore, RNA mis-splicing in human breast cancers correlates with innate and adaptive immune signatures, especially in MYC-amplified tumors that are typically immune cold. These findings indicate that dsRNA-sensing pathways respond to global aberrations of RNA splicing in cancer and provoke the hypothesis that STTs may provide unexplored strategies to activate anti-tumor immune pathways.
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Antivirales/farmacología , Inmunidad/efectos de los fármacos , Empalmosomas/metabolismo , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/patología , Inmunidad Adaptativa/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Femenino , Amplificación de Genes/efectos de los fármacos , Humanos , Intrones/genética , Ratones , Terapia Molecular Dirigida , Proteínas Proto-Oncogénicas c-myc/metabolismo , Empalme del ARN/efectos de los fármacos , Empalme del ARN/genética , ARN Bicatenario/metabolismo , Transducción de Señal/efectos de los fármacos , Empalmosomas/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/genéticaRESUMEN
BACKGROUND: The early detection of dementia depends on efficient methods for the assessment of cognitive capacity. Existing cognitive screening tools are ill-suited to the differentiation of cognitive status, particularly when dealing with early-stage impairment. METHODS: The study included 8,979 individuals (> 50 years) with unimpaired cognitive functions, mild cognitive impairment (MCI), or dementia. This study sought to determine optimal cutoffs values for the Cognitive Abilities Screening Instrument (CASI) aimed at differentiating between individuals with or without dementia as well as between individuals with or without mild cognitive impairment. Cox proportional hazards models were used to evaluate the value of CASI tasks in predicting conversion from MCI to all-cause dementia, dementia of Alzheimer's type (DAT), or to vascular dementia (VaD). RESULTS: Our optimized cutoff scores achieved high accuracy in differentiating between individuals with or without dementia (AUC = 0.87-0.93) and moderate accuracy in differentiating between CU and MCI individuals (AUC = 0.67 - 0.74). Among individuals without cognitive impairment, scores that were at least 1.5 × the standard deviation below the mean scores on CASI memory tasks were predictive of conversion to dementia within roughly 2 years after the first assessment (all-cause dementia: hazard ratio [HR] = 2.81 - 3.53; DAT: 1.28 - 1.49; VaD: 1.58). Note that the cutoff scores derived in this study were lower than those reported in previous studies. CONCLUSION: Our results in this study underline the importance of establishing optimal cutoff scores for individuals with specific demographic characteristics and establishing profiles by which to guide CASI analysis.
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Enfermedad de Alzheimer , Trastornos del Conocimiento , Disfunción Cognitiva , Demencia Vascular , Humanos , Enfermedad de Alzheimer/diagnóstico , Taiwán/epidemiología , Disfunción Cognitiva/diagnóstico , Trastornos del Conocimiento/diagnóstico , Demencia Vascular/diagnóstico , Cognición , Pruebas NeuropsicológicasRESUMEN
The major challenge in COVID-19 vaccine effectiveness is immune escape by SARS-CoV-2 variants. To overcome this, an Omicron-specific messenger RNA (mRNA) vaccine was designed. The extracellular domain of the spike of the Omicron variant was fused with a modified GCN4 trimerization domain with low immunogenicity (TSomi). After immunization with TSomi mRNA in hamsters, animals were challenged with SARS-CoV-2 virus. The raised nonneutralizing antibodies or cytokine secretion responses can recognize both Wuhan S and Omicron S. However, the raised antibodies neutralized SARS-CoV-2 Omicron virus infection but failed to generate Wuhan virus neutralizing antibodies. Surprisingly, TSomi mRNA immunization protected animals from Wuhan virus challenge. These data indicated that non-neutralizing antibodies or cellular immunity may play a more important role in vaccine-induced protection than previously believed. Next-generation COVID-19 vaccines using the Omicron S antigen may provide sufficient protection against ancestral or current SARS-CoV-2 variants.
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Antígenos de Grupos Sanguíneos , COVID-19 , Animales , Cricetinae , Humanos , SARS-CoV-2/genética , Vacunas contra la COVID-19 , Anticuerpos Neutralizantes , COVID-19/prevención & control , ARN Mensajero/genética , Vacunas de ARNm , Anticuerpos Antivirales , Glicoproteína de la Espiga del Coronavirus/genéticaRESUMEN
BACKGROUND: Acute bronchiolitis and air pollution are both risk factor of pediatric asthma. This study aimed to assess subsequent exposure to air pollutants related to the inception of preschool asthma in infants with acute bronchiolitis. This study aimed to assess subsequent exposure to air pollutants related to the inception of preschool asthma in infants with acute bronchiolitis. METHODS: A nested case-control retrospective study was performed at the Kaohsiung Medical University Hospital systems between 2009 and 2019. The average concentration of PM10, PM2.5, SO2, NO, NO2, and NOX was collected for three, six, and twelve months after the first infected episode. Adjusted regression models were employed to evaluate the association between asthma and air pollution exposure after bronchiolitis. RESULTS: Two thousand six hundred thirty-seven children with acute bronchiolitis were included. Exposure to PM10, PM2.5, SO2, NO, NO2, and NOX in the three, six, and twelve months following an episode of bronchiolitis was found to significantly increase the risk of preschool asthma in infants with a history of bronchiolitis.(OR, 95%CI: PM10 = 1.517-1.559, 1.354-1.744; PM2.5 = 2.510-2.603, 2.148-3.061; SO2 = 1.970-2.040, 1.724-2.342; ; NO = 1.915-1.950, 1.647-2.272; NO2 = 1.915-1.950, 1.647-2.272; NOX = 1.752-1.970, 1.508-2.252) In a sensitive analysis of hospitalized infants, only PM10, PM2.5, SO2, and NO were found to have significant effects during all time periods. (OR, 95%CI: PM10 = 1.613-1.650, 1.240-2.140; PM2.5 = 2.208-2.286, 1.568-3.061; SO2 = 1.679-1.622, 1.197-2.292; NO = 1.525-1.557, 1.094-2.181) CONCLUSION: The presence of ambient PM10, PM2.5, SO2 and NO in the three, six, and twelve months following an episode of acute bronchiolitis has been linked to the development of preschool asthma in infants with a history of acute bronchiolitis.
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Contaminantes Atmosféricos , Contaminación del Aire , Asma , Bronquiolitis , Lactante , Niño , Preescolar , Humanos , Estudios de Casos y Controles , Estudios Retrospectivos , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Asma/epidemiología , Factores de Riesgo , Bronquiolitis/inducido químicamente , Bronquiolitis/epidemiología , Material Particulado/efectos adversos , Material Particulado/análisis , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Dióxido de Nitrógeno/efectos adversos , Dióxido de Nitrógeno/análisisRESUMEN
Asthma is a chronic inflammatory airway disease characterized by variable airflow obstruction, bronchial hyper-responsiveness, and airway inflammation. The chronic inflammation of the airway is mediated by many cell types, cytokines, chemokines, and inflammatory mediators. Research suggests that exposure to air pollution has a negative impact on asthma outcomes in adult and pediatric populations. Air pollution is one of the greatest environmental risks to health, and it impacts the lungs' innate and adaptive defense systems. A major pollutant in the air is particulate matter (PM), a complex component composed of elemental carbon and heavy metals. According to the WHO, 99% of people live in air pollution where air quality levels are lower than the WHO air quality guidelines. This suggests that the effect of air pollution exposure on asthma is a crucial health issue worldwide. Macrophages are essential in recognizing and processing any inhaled foreign material, such as PM. Alveolar macrophages are one of the predominant cell types that process and remove inhaled PM by secreting proinflammatory mediators from the lung. This review focuses on macrophages and their role in orchestrating the inflammatory responses induced by exposure to air pollutants in asthma.
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Contaminantes Atmosféricos , Contaminación del Aire , Asma , Humanos , Adulto , Niño , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Asma/metabolismo , Material Particulado/efectos adversos , Material Particulado/análisis , Macrófagos Alveolares/metabolismo , Inflamación , Citocinas/metabolismo , Mediadores de Inflamación , Carbono , Exposición a Riesgos Ambientales/efectos adversosRESUMEN
Severe acute respiratory syndrome coronavirus 2 is a new, highly pathogenic virus that has recently elicited a global pandemic called the 2019 coronavirus disease (COVID-19). COVID-19 is characterized by significant immune dysfunction, which is caused by strong but unregulated innate immunity with depressed adaptive immunity. Reduced and delayed responses to interferons (IFN-I/IFN-III) can increase the synthesis of proinflammatory cytokines and extensive immune cell infiltration into the airways, leading to pulmonary disease. The development of effective treatments for severe COVID-19 patients relies on our knowledge of the pathophysiological components of this imbalanced innate immune response. Strategies to address innate response factors will be essential. Significant efforts are currently underway to develop vaccines against SARS-CoV-2. COVID-19 vaccines, such as inactivated DNA, mRNA, and protein subunit vaccines, have already been applied in clinical use. Various vaccines display different levels of effectiveness, and it is important to continue to optimize and update their composition in order to increase their effectiveness. However, due to the continuous emergence of variant viruses, improving the immunity of the general public may also increase the effectiveness of the vaccines. Many observational studies have demonstrated that serum levels of vitamin D are inversely correlated with the incidence or severity of COVID-19. Extensive evidence has shown that vitamin D supplementation could be vital in mitigating the progression of COVID-19 to reduce its severity. Vitamin D defends against SARS-CoV-2 through a complex mechanism through interactions between the modulation of innate and adaptive immune reactions, ACE2 expression, and inhibition of the renin-angiotensin system (RAS). However, it remains unclear whether Vit-D also plays an important role in the effectiveness of different COVID-19 vaccines. Based on analysis of the molecular mechanism involved, we speculated that vit-D, via various immune signaling pathways, plays a complementary role in the development of vaccine efficacy.
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Vacunas contra la COVID-19/administración & dosificación , COVID-19/prevención & control , Vitamina D/administración & dosificación , Vitamina D/sangre , Animales , COVID-19/sangre , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Ensayos Clínicos como Asunto , Humanos , Inmunogenicidad Vacunal , Pandemias/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2/aislamiento & purificación , Vitamina D/inmunologíaRESUMEN
Background and Purpose- The observation that smokers with stroke could have better outcome than nonsmokers led to the term "smoking paradox." The controversy of such a complex claim has not been fully settled, even though different case mix was noted. Analyses were conducted on 2 independent data sets to evaluate and determine whether such a paradox truly exists. Methods- Taiwan Stroke Registry with 88 925 stroke cases, and MJ cohort with 541 047 adults participating in a medical screening program with 1630 stroke deaths developed during 15 years of follow-up (1994-2008). Primary outcome for stroke registry was functional independence at 3 months by modified Rankin Scale score ≤2, for individuals classified by National Institutes of Health Stroke Scale score at admission. For MJ cohort, mortality risk by smoking status or by stroke history was assessed by hazard ratio. Results- A >11-year age difference in stroke incidence was found between smokers and nonsmokers, with a median age of 60.2 years for current smokers and 71.6 years for nonsmokers. For smokers, favorable outcome in mortality and in functional assessment in 3 months with modified Rankin Scale score ≤2 stratified by the National Institutes of Health Stroke Scale score was present but disappeared when age and sex were matched. Smokers without stroke history had a ≈2-fold increase in stroke deaths (2.05 for ischemic stroke and 1.53 for hemorrhagic stroke) but smokers with stroke history, 7.83-fold increase, overshadowing smoking risk. Quitting smoking at earlier age reversed or improved outcome. Conclusions- "The more you smoke, the earlier you stroke, and the longer sufferings you have to cope." Smokers had 2-fold mortality from stroke but endured stroke disability 11 years longer. Quitting early reduced or reversed the harms.
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Bases de Datos Factuales/tendencias , Fumar/epidemiología , Fumar/tendencias , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Sobrevivientes , Adulto , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros , Autoinforme , Fumar/efectos adversos , Taiwán/epidemiología , Adulto JovenRESUMEN
BACKGROUND: Renal function is a key factor of cardiovascular disease. Carotid intima-media thickness (IMT) has been widely used as a marker of early subclinical atherosclerosis. The determinants of cystatin C, a novel marker of renal function, have not been extensively studied in the Asian population. This study aimed to assess the determinants of cystatin C and explore whether carotid thickening was associated with urinary albumin-creatinine ratio and cystatin C in community-living Taiwanese adults. METHODS: A cross-sectional study was conducted on participants from Taichung City, Taiwan. All the participants underwent carotid ultrasonography. Carotid IMT-mean and IMT-maximum were derived. Kidney biomarkers were measured on the basis of urinary albumin-to-creatinine ratio (ACR) and cystatin C. Multiple linear regression analysis was used. RESULTS: A total of 1032 individuals were recruited, and 469 (45.44%) of them were men. An increased cystatin C level was significantly associated with older age, male gender, lack of physical activity, low HDL cholesterol, abdominal obesity, high hs-CRP, and high ACR. The multivariate-adjusted mean carotid IMT-mean and IMT-maximum values significantly increased by 80.49 and 195.23 µm for every one unit of increase in cystatin C level and by 0.07 and 0.14 µm for every one unit of increase in ACR, respectively (all p < 0.001 except ACR on IMT-maximum with p < 0.01). Lack of physical activity, low HDL, abdominal obesity, high hs-CRP, and high ACR were the determinants of cystatin C. CONCLUSION: Cystatin C and ACR were strongly and linearly associated with carotid thickening, a marker of subclinical atherosclerosis.
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Albuminuria , Aterosclerosis/diagnóstico , Grosor Intima-Media Carotídeo , Creatinina/orina , Cistatina C/sangre , Anciano , Anciano de 80 o más Años , Aterosclerosis/sangre , Aterosclerosis/orina , Biomarcadores/sangre , Arterias Carótidas/diagnóstico por imagen , Estudios Transversales , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Persona de Mediana Edad , Taiwán , UltrasonografíaRESUMEN
Interfacing electrochemical sensors in a lab-on-a-disc (LoD) system with a potentiostat is often tedious and challenging. We here present the first multichannel, modular, lightweight, and wirelessly powered, custom-built potentiostat-on-a-disc (PoD) for centrifugal microfluidic applications. The developed potentiostat is in the form factor of a typical digital video disc (DVD) and weighs only 127 g. The design of the potentiostat facilitates easy and robust interfacing with the electrodes in the LoD system, while enabling real-time electrochemical detection during rotation. The device can perform different electroanalytical techniques such as cyclic voltammetry, square wave voltammetry, and amperometry while being controlled by custom-made software. Measurements were conducted with and without rotation using both in-house fabricated and commercial electrodes. The performance of the PoD was in good agreement with the results obtained using a commercial potentiostat with a measured current resolution of 200 pA. As a proof of concept, we performed a real-time release study of an electrochemically active compound from microdevices used for drug delivery.
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BACKGROUND: The natural history of vertebrobasilar artery (VBA) stenosis or occlusion remains understudied. METHODS: Patients with diagnosis of ischemic stroke or transient ischemic attack (TIA) who were noted to have VBA stenosis based on computed tomography or magnetic resonance imaging or catheter-based angiogram were selected from Taiwan Stroke Registry. Cox proportional hazards model was used to determine the hazards ratio (HR) of recurrent stroke and death within 1 year of index event in various groups based on severity of VBA stenosis (none to mild: 0-49%; moderate to severe: 50-99%: occlusion: 100%) after adjusting for differences in demographic and clinical characteristics between groups at baseline evaluation. RESULTS: None to mild or moderate to severe VBA stenosis was diagnosed in 6972 (66%) and 3,137 (29.8%) among 10,515 patients, respectively, and occlusion was identified in 406 (3.8%) patients. Comparing with patients who showed none to mild stenosis of VBA, there was a significantly higher risk of recurrent stroke (HR 1.21, 95% CI 1.01-1.45) among patients with moderate to severe VBA stenosis. There was a nonsignificantly higher risk of recurrent stroke (HR 1.49, 95% CI 0.99-2.22) and significantly higher risk of death (HR 2.21, 95% CI 1.72-2.83), among patients with VBA occlusion after adjustment of potential confounders. CONCLUSIONS: VBA stenosis or occlusion was relatively prevalent among patients with TIA or ischemic stroke and associated with higher risk of recurrent stroke and death in patients with ischemic stroke or TIA who had large artery atherosclerosis.
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Accidente Cerebrovascular/epidemiología , Insuficiencia Vertebrobasilar/epidemiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Recurrencia , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/mortalidad , Taiwán/epidemiología , Factores de Tiempo , Insuficiencia Vertebrobasilar/diagnóstico por imagen , Insuficiencia Vertebrobasilar/mortalidadRESUMEN
L5, the most electronegative and atherogenic subfraction of low-density lipoprotein (LDL), induces platelet activation. We hypothesized that plasma L5 levels are increased in acute ischemic stroke patients and examined whether lectin-like oxidized LDL receptor-1 (LOX-1), the receptor for L5 on endothelial cells and platelets, plays a critical role in stroke. Because amyloid ß (Aß) stimulates platelet aggregation, we studied whether L5 and Aß function synergistically to induce prothrombotic pathways leading to stroke. Levels of plasma L5, serum Aß, and platelet LOX-1 expression were significantly higher in acute ischemic stroke patients than in controls without metabolic syndrome (P < .01). In mice subjected to focal cerebral ischemia, L5 treatment resulted in larger infarction volumes than did phosphate-buffered saline treatment. Deficiency or neutralizing of LOX-1 reduced infarct volume up to threefold after focal cerebral ischemia in mice, illustrating the importance of LOX-1 in stroke injury. In human platelets, L5 but not L1 (the least electronegative LDL subfraction) induced Aß release via IκB kinase 2 (IKK2). Furthermore, L5+Aß synergistically induced glycoprotein IIb/IIIa receptor activation; phosphorylation of IKK2, IκBα, p65, and c-Jun N-terminal kinase 1; and platelet aggregation. These effects were blocked by inhibiting IKK2, LOX-1, or nuclear factor-κB (NF-κB). Injecting L5+Aß shortened tail-bleeding time by 50% (n = 12; P < .05 vs L1-injected mice), which was prevented by the IKK2 inhibitor. Our findings suggest that, through LOX-1, atherogenic L5 potentiates Aß-mediated platelet activation, platelet aggregation, and hemostasis via IKK2/NF-κB signaling. L5 elevation may be a risk factor for cerebral atherothrombosis, and downregulating LOX-1 and inhibiting IKK2 may be novel antithrombotic strategies.
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Isquemia Encefálica/sangre , Lipoproteínas LDL/sangre , Agregación Plaquetaria , Accidente Cerebrovascular/sangre , Péptidos beta-Amiloides/sangre , Animales , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Quinasa I-kappa B/metabolismo , Arteriosclerosis Intracraneal/sangre , Arteriosclerosis Intracraneal/patología , Trombosis Intracraneal/sangre , Trombosis Intracraneal/patología , Masculino , Ratones , Ratones Noqueados , Receptores Depuradores de Clase E/metabolismo , Transducción de Señal , Accidente Cerebrovascular/patologíaRESUMEN
Wavelength widely tunable femtosecond sources can be implemented by optically filtering the leftmost/rightmost spectral lobes of a broadened spectrum due to self-phase modulation (SPM) dominated fiber-optic nonlinearities. We numerically and experimentally investigate the feasibility of implementing such a tunable source inside optical fibers with negative group-velocity dispersion (GVD). We show that the spectral broadening prior to soliton fission is dominated by SPM and generates well-isolated spectral lobes; filtering the leftmost/rightmost spectral lobes results in energetic femtosecond pulses with the wavelength tuning range more than 400 nm. Employing an ultrafast Er-fiber laser and a dispersion-shifted fiber with negative GVD, we implement an energetic tunable source that produces ~100-fs pulses tunable between 1.3 µm and 1.7 µm with up to ~16-nJ pulse energy. Further energy scaling is achieved by increasing the input pulse energy to ~1-µJ and reducing the fiber length to 1.3 cm. The resulting source can produce >100-nJ femtosecond pulses at 1.3 µm and 1.7 µm with MW level peak power, representing an order of magnitude improvement of our previous results. Such a powerful source covers the 2nd and the 3rd biological transmission window and can facilitate multiphoton deep-tissue imaging.
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We demonstrate that energetic femtosecond pulses tunable from 1.3 to 1.7 µm can be achieved using self-phase modulation enabled spectral broadening followed by spectral lobe filtering. Based on a home-built 5-W Er-fiber laser system operating at 31-MHz repetition rate, we obtain femtosecond pulses that can be continuously tuned from 1.3 to 1.7 µm with >4.5 nJ pulse energy. We further optimize the spectral broadening process using a fiber with larger mode area and scale up the pulse energy to >10 nJ; the resulting pulse duration is as short as ~50 fs. Such a widely tunable, energetic femtosecond source is well suited for driving a laser scanning microscope to perform deep tissue multiphoton microscopy.
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We demonstrate an energy scalable approach to implement ultrafast fiber laser sources suitable for deep tissue multi-photon microscopy imaging. Enabled by fiber-optic nonlinearities (dominated by self-phase modulation), these unique ultrafast sources produce nearly transform-limited pulses of 50-90 fs in duration with the center wavelength tunable in the wavelength range of 1030-1215 nm. The resulting pulse energy can be scaled up to 20 nJ by optimizing fiber dispersion, shortening fiber length, and using large-mode-area fibers. We applied such an energetic source to a proof-of-principle study of ex vivo human skin based on harmonics (i.e., second-harmonic generation and third-harmonic generation) imaging. This new type of fiber-format energetic ultrafast source provides a robust solution for multiphoton microscopy applications.
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This study presents the low cost fabrication of flexible white-light-emitting diodes (w-LEDs) with nano-honeycomb-structured phosphor films. Extending the dimensions of the nano-honeycomb structures improved the color uniformity of the flexible samples, and the 950-nm pattern sample demonstrated optimal color uniformity because this nano-pattern exhibited an excellent diffusion ability owing to its pitch size. In addition to color uniformity, the use of this nano-pattern improved the luminous efficiency. The 750-nm pattern exhibited the highest luminous efficiency (235.8 lm/W), which was approximately 7% higher than that exhibited by a non-patterned phosphor film sample. Thus, flexible w-LEDs with nano-honeycomb structure optimization have great potential to be used as next-generation lighting sources.
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BACKGROUND: Although vertebrates are bilaterally symmetric organisms, their internal organs are distributed asymmetrically along a left-right axis. Disruption of left-right axis asymmetric patterning often occurs in human genetic disorders. In zebrafish embryos, Kupffer's vesicle, like the mouse node, breaks symmetry by inducing asymmetric expression of the Nodal-related gene, spaw, in the left lateral plate mesoderm (LPM). Spaw then stimulates transcription of itself and downstream genes, including lft1, lft2, and pitx2, specifically in the left side of the diencephalon, heart and LPM. This developmental step is essential to establish subsequent asymmetric organ positioning. In this study, we evaluated the role of krüppel-like factor 8 (klf8) in regulating left-right asymmetric patterning in zebrafish embryos. METHODS: Zebrafish klf8 expression was disrupted by both morpholino antisense oligomer-mediated knockdown and a CRISPR-Cas9 system. Whole-mount in situ hybridization was conducted to evaluate gene expression patterns of Nodal signalling components and the positions of heart and visceral organs. Dorsal forerunner cell number was evaluated in Tg(sox17:gfp) embryos and the length and number of cilia in Kupffer's vesicle were analyzed by immunocytochemistry using an acetylated tubulin antibody. RESULTS: Heart jogging, looping and visceral organ positioning were all defective in zebrafish klf8 morphants. At the 18-22 s stages, klf8 morphants showed reduced expression of genes encoding Nodal signalling components (spaw, lft1, lft2, and pitx2) in the left LPM, diencephalon, and heart. Co-injection of klf8 mRNA with klf8 morpholino partially rescued spaw expression. Furthermore, klf8 but not klf8â³zf overexpressing embryos showed dysregulated bilateral expression of Nodal signalling components at late somite stages. At the 10s stage, klf8 morphants exhibited reductions in length and number of cilia in Kupffer's vesicle, while at 75% epiboly, fewer dorsal forerunner cells were observed. Interestingly, klf8 mutant embryos, generated by a CRISPR-Cas9 system, showed bilateral spaw expression in the LPM at late somite stages. This observation may be partly attributed to compensatory upregulation of klf12b, because klf12b knockdown reduced the percentage of klf8 mutants exhibiting bilateral spaw expression. CONCLUSIONS: Our results demonstrate that zebrafish Klf8 regulates left-right asymmetric patterning by modulating both Kupffer's vesicle morphogenesis and spaw expression in the left LPM.
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Tipificación del Cuerpo/genética , Regulación del Desarrollo de la Expresión Génica/genética , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Factor de Crecimiento Transformador beta2/genética , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Pez Cebra/embriología , Pez Cebra/genética , Animales , Morfogénesis/genética , Factor de Crecimiento Transformador beta2/metabolismoRESUMEN
BACKGROUND: We investigated the impact of serum cholesterol levels on 30-day mortality after ischemic stroke in dialysis patients. METHODS: From the Taiwan Stroke Registry data, we identified 46,770 ischemic stroke cases, including 1101 dialysis patients and 45,669 nondialysis patients from 2006 to 2013. RESULTS: Overall, the 30-day mortality was 1.46-fold greater in the dialysis group than in the nondialysis group (1.75 versus 1.20 per 1000 person-days). The mortality rates were 1.64, .62, 2.82, and 2.23 per 1000 person-days in dialysis patients with serum total cholesterol levels of <120 mg/dL, 120-159 mg/dL, 160-199 mg/dL, and ≥200 mg/dL, respectively. Compared to dialysis patients with serum total cholesterol levels of 120-159 mg/dL, the corresponding adjusted hazard ratios of mortality were 4.20 (95% confidence interval [CI] = 1.01-17.4), 8.06 (95% CI = 2.02-32.2), and 6.89 (95% CI = 1.59-29.8) for those with cholesterol levels of <120 mg/dL, 160-199 mg/dL, and ≥200 mg/dL, respectively. CONCLUSIONS: Dialysis patients with serum total cholesterol levels of ≥160 mg/dL or <120 mg/dL on admission are at an elevated hazard of 30-day mortality after ischemic stroke.