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1.
BMC Med Inform Decis Mak ; 24(1): 149, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822293

RESUMEN

BACKGROUND: Epilepsy, a chronic brain disorder characterized by abnormal brain activity that causes seizures and other symptoms, is typically treated using anti-epileptic drugs (AEDs) as the first-line therapy. However, due to the variations in their modes of action, identification of effective AEDs often relies on ad hoc trials, which is particularly challenging for pediatric patients. Thus, there is significant value in computational methods capable of assisting in the selection of AEDs, aiming to minimize unnecessary medication and improve treatment efficacy. RESULTS: In this study, we collected 7,507 medical records from 1,000 pediatric epilepsy patients and developed a computational clinical decision-supporting system for AED selection. This system leverages three multi-channel convolutional neural network (CNN) models tailored to three specific AEDs (vigabatrin, prednisolone, and clobazam). Each CNN model predicts whether a respective AED is effective on a given patient or not. The CNN models showed AUROCs of 0.90, 0.80, and 0.92 in 10-fold cross-validation, respectively. Evaluation on a hold-out test dataset further revealed positive predictive values (PPVs) of 0.92, 0.97, and 0.91 for the three respective CNN models, representing that suggested AEDs by our models would be effective in controlling epilepsy with a high accuracy and thereby reducing unnecessary medications for pediatric patients. CONCLUSION: Our CNN models in the system demonstrated high PPVs for the three AEDs, which signifies the potential of our approach to support the clinical decision-making by assisting doctors in recommending effective AEDs within the three AEDs for patients based on their medical history. This would result in a reduction in the number of unnecessary ad hoc attempts to find an effective AED for pediatric epilepsy patients.


Asunto(s)
Anticonvulsivantes , Sistemas de Apoyo a Decisiones Clínicas , Aprendizaje Profundo , Epilepsia , Humanos , Epilepsia/tratamiento farmacológico , Anticonvulsivantes/uso terapéutico , Niño , Preescolar , Adolescente , Femenino , Masculino , Anamnesis , Lactante
2.
Exp Ther Med ; 26(3): 446, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37614435

RESUMEN

As a type of contact dermatitis (CD), irritant CD (ICD) is an acute skin inflammation caused by external irritants, such as soap, water and chemicals. Humulus japonicus (HJ) is a herbal medicine widely distributed in Asian countries and has anti-inflammatory, antimicrobial and antioxidant effects. The current study aimed to investigate the anti-dermatitis effect of HJ on ICD and determine the molecular basis of this effect using 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced dermatitis mice models and lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Mice were orally administered HJ and luteolin, the major compound in HJ, and topically administered TPA on the right ear to induce dermatitis. Topical application of TPA induced ear redness, oedema and increased infiltration of neutrophils and macrophages, which ameliorated following HJ and luteolin administration. The gene expression levels of inflammatory cell migrating chemokines, chemokine ligand 3 (CCL3) and chemokine (C-X-C motif) ligand 2 (CXCL2), and pro-inflammatory cytokine, IL-1ß, were reduced in the ears of HJ- and luteolin-treated mice. HJ and luteolin also inhibited the gene expression of chemokines, CCL3 and CXCL2, and pro-inflammatory cytokines, IL-1ß, IL-6 and TNF-α, in LPS-stimulated RAW264.7 cells. Moreover, HJ and luteolin decreased the expression levels of two key inflammatory enzymes, cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS), and total and active phosphorylation of NF-κB p65. These results suggest that HJ could have a protective effect against ICD by suppressing inflammatory responses; therefore, HJ is a promising therapeutic strategy for ICD treatment.

3.
Pharmaceutics ; 15(7)2023 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-37514189

RESUMEN

Although the promise of cancer immunotherapy has been partially fulfilled with the unprecedented clinical success of several immunotherapeutic interventions, some issues, such as limited response rate and immunotoxicity, still remain. Metalloimmunotherapy offers a new form of cancer immunotherapy that utilizes the inherent immunomodulatory features of metal ions to enhance anticancer immune responses. Their versatile functionalities for a multitude of direct and indirect anticancer activities together with their inherent biocompatibility suggest that metal ions can help overcome the current issues associated with cancer immunotherapy. However, metal ions exhibit poor drug-like properties due to their intrinsic physicochemical profiles that impede in vivo pharmacological performance, thus necessitating an effective pharmaceutical formulation strategy to improve their in vivo behavior. Metal-based nanoparticles provide a promising platform technology for reshaping metal ions into more drug-like formulations with nano-enabled engineering approaches. This review provides a general overview of cancer immunotherapy, the immune system and how it works against cancer cells, and the role of metal ions in the host response and immune modulation, as well as the impact of metal ions on the process via the regulation of immune cells. The preclinical studies that have demonstrated the potential of metal-based nanoparticles for cancer metalloimmunotherapy are presented for the representative nanoparticles constructed with manganese, zinc, iron, copper, calcium, and sodium ions. Lastly, the perspectives and future directions of metal-based nanoparticles are discussed, particularly with respect to their clinical applications.

4.
Water Res ; 229: 119407, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36462260

RESUMEN

This study provides a comprehensive and systematic overview of the application of gas-liquid two-phase flow with microbubbles in the feed stream to improve heat and mass transfer in direct-contact membrane distillation (DCMD) processes for seawater desalination. A swirl-flow-type microbubble generator (MBG) was installed at the feed-side inlet of the DCMD module to investigate its effect on transmembrane flux. The maximum improvement in the MBG-assisted DCMD permeation flux was found to be approximately 18% at a lower feed temperature (40 °C) and optimal air flow rate (50 cc/min), and an optimal MBG geometry comprising a swirler, a nozzle tip of diameter 2 mm, and a diffuser at an angle of 30°. The results were observed to be related to the number density of microbubbles less than 100 µm in size, which plays an important role in improving heat and mass transfer in two-phase flow. In addition, the simulation results based on conventional heat transfer correlations of bubbly flow underestimated the experimental results. Therefore, this study also aims to propose and verify a new two-phase flow heat transfer correlation. The proposed correlation considers the effects of bubble size distribution to accurately predict the performance of MBG-assisted DCMD processes.


Asunto(s)
Microburbujas , Purificación del Agua , Destilación/métodos , Membranas Artificiales , Temperatura , Purificación del Agua/métodos
5.
Environ Sci Process Impacts ; 25(11): 1771-1787, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36341487

RESUMEN

High-resolution mass spectrometry was used to screen for emerging per- and polyfluorinated alkyl substances (PFAS) in precipitation samples collected in summer 2019 at seven sites in the United States. We previously quantified the concentration of ten PFAS in the rainwater samples using the method of isotopic dilution (Pike et al., 2021). Nine of these targeted analytes belonged to the U.S. Environmental Protection Agency Regional Screening Level list, herein referred to as EPA-monitored analytes. In this new work, we identify emerging PFAS compounds by liquid chromatography quadrupole time-of-flight mass spectrometry. Several emerging PFAS were detected across all samples, with the most prevalent compounds being C3-C8 hydrogen-substituted perfluorocarboxylic acids (H-PFCAs) and fluorotelomer carboxylic acids (FTCAs). Concentrations of emerging PFAS were in the 10-1000 ng L-1 range (approximately 1-2 orders of magnitude greater than EPA-monitored PFAS) at all sites except Wooster, OH, where concentrations were even higher, with a maximum estimated ΣPFAS of 16 400 ng L-1. The elevated levels of emerging PFAS in the Wooster samples were predominantly even and odd chain-length H-PFCAs and FTCAs comprised of complex mixtures of branched isomers. This unique composition did not match any known manufactured PFAS formulation reported to date, but it could represent thermally transformed by-products emitted by a local point source. Overall, the results indicate that PFAS outside of the standard analyte lists make up a significant and previously unappreciated fraction of contaminants in rainwater collected within the central U.S.-and potentially world-wide-especially in proximity to localized point sources.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Estados Unidos , Fluorocarburos/análisis , Monitoreo del Ambiente/métodos , Cromatografía Liquida , Espectrometría de Masas , Ácidos Carboxílicos/análisis , Contaminantes Químicos del Agua/análisis
6.
Int J Mol Sci ; 23(22)2022 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-36430486

RESUMEN

Fulminant hepatitis is characterized by rapid and massive immune-mediated liver injury. Dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome, gene 1 (DAX1; NR0B1) represses the transcription of various genes. Here, we determine whether DAX1 serves as a regulator of inflammatory liver injury induced by concanavalin A (ConA). C57BL/6J (WT), myeloid cell-specific Dax1 knockout (MKO), and hepatocyte-specific Dax1 knockout (LKO) mice received single intravenous administration of ConA. Histopathological changes in liver and plasma alanine aminotransferase and aspartate aminotransferase levels in Dax1 MKO mice were comparable with those in WT mice following ConA administration. Unlike Dax1 MKO mice, Dax1 LKO mice were greatly susceptible to ConA-induced liver injury, which was accompanied by enhanced infiltration of immune cells, particularly CD4+ and CD8+ T cells, in the liver. Factors related to T-cell recruitment, including chemokines and adhesion molecules, significantly increased following enhanced and prolonged phosphorylation of NF-κB p65 in the liver of ConA-administered Dax1 LKO mice. This is the first study to demonstrate that hepatocyte-specific DAX1 deficiency exacerbates inflammatory liver injury via NF-κB p65 activation, thereby causing T-cell infiltration by modulating inflammatory chemokines and adhesion molecules. Our results suggest DAX1 as a therapeutic target for fulminant hepatitis treatment.


Asunto(s)
Linfocitos T CD8-positivos , Necrosis Hepática Masiva , Ratones , Animales , FN-kappa B , Ratones Endogámicos C57BL , Hepatocitos , Transducción de Señal , Concanavalina A/toxicidad , Linfocitos T CD4-Positivos
7.
Int J Mol Sci ; 23(19)2022 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-36233086

RESUMEN

Acetaminophen (APAP) is a widely used analgesic and antipyretic drug, but its overdose can cause acute liver failure. The dosage-sensitive sex reversal adrenal hypoplasia congenita critical region on the X chromosome, gene 1 (DAX-1, NR0B1), is an orphan nuclear receptor that acts as a transcriptional co-repressor of various genes. In this study, we identified the role of DAX-1 in APAP-induced liver injury using hepatocyte-specific Dax-1 knockout (Dax-1 LKO) mice. Mouse primary hepatocytes were used as a comparative in vitro study. APAP overdose led to decreased plasma alanine aminotransferase and aspartate aminotransferase levels in Dax-1 LKO mice compared to C57BL/6J (WT) controls, accompanied by reduced liver necrosis. The expression of the genes encoding the enzymes catalyzing glutathione (GSH) synthesis and metabolism and antioxidant enzymes was increased in the livers of APAP-treated Dax-1 LKO mice. The rapid recovery of GSH levels in the mitochondrial fraction of APAP-treated Dax-1 LKO mice led to reduced reactive oxygen species levels, resulting in the inhibition of the prolonged JNK activation. The hepatocyte-specific DAX-1 deficiency increased the protein expression of nuclear factor erythroid 2-related factor 2 (Nrf2) compared with WT controls after APAP administration. These results indicate that DAX-1 deficiency in hepatocytes protects against APAP-induced liver injury by Nrf2-regulated antioxidant defense.


Asunto(s)
Antipiréticos , Enfermedad Hepática Inducida por Sustancias y Drogas , Receptor Nuclear Huérfano DAX-1 , Factor 2 Relacionado con NF-E2 , Acetaminofén/toxicidad , Alanina Transaminasa/metabolismo , Animales , Antioxidantes/metabolismo , Aspartato Aminotransferasas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Proteínas Co-Represoras/metabolismo , Receptor Nuclear Huérfano DAX-1/genética , Glutatión/metabolismo , Hepatocitos/metabolismo , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Receptores Nucleares Huérfanos/metabolismo , Especies Reactivas de Oxígeno/metabolismo
8.
Pediatr Gastroenterol Hepatol Nutr ; 25(5): 432-440, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36148287

RESUMEN

Purpose: Eating disorders often result in somatic complications, including cardiac abnormalities. Cardiac abnormalities may involve any part of the heart, including the cardiac conduction system, and can lead to sudden cardiac death. The current study aimed to evaluate the incidence of cardiac complications in pediatric patients with eating disorders and their associated factors. Methods: We retrospectively analyzed patients aged 10-18 years who were diagnosed with DSM-V (Diagnostic and Statistical Manual of Mental Disorder-V) eating disorders and underwent electrocardiography (ECG) and/or echocardiography between January 2015 and May 2020. Results: In total, 127 patients were included, of whom 113 (89.0%) were female. The median body mass index (BMI) was 15.05±3.69 kg/m2. Overall, 74 patients (58.3%) had ECG abnormalities, with sinus bradycardia being the most common abnormality (91.9%). Patients with ECG abnormalities had significantly lower BMI (14.35±2.78 kg/m2 vs. 16.06± 4.55 kg/m2, p<0.001) than patients without ECG abnormalities, as well as lower phosphorus and higher cholesterol levels. Among the 46 patients who underwent echocardiographic evaluation, 23 (50.0%) had echocardiographic abnormalities, with pericardial effusion being the most common (60.9%). The median left ventricular mass (LVM) and ejection fraction were 67.97±21.25 g and 66.91±28.76%, respectively. LVM and BMI showed a positive correlation (r=0.604, p<0.001). After weight gain, the amount of pericardial effusion was reduced in 3 patients, and 30 patients presented with normal ECG findings. Conclusion: Cardiac abnormalities are relatively frequent in patients with eating disorders. Physicians should focus on this somatic complication and careful monitoring is required.

9.
J Poult Sci ; 59(3): 233-246, 2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35989693

RESUMEN

We aimed to compare the combinatorial effect of 3,4,5-trihydroxybenzoic acid (THB) and oregano extracts (OE) with THB alone on the growth performance and elimination of deleterious effects in coccidiosis-infected broilers. A total of 210 one-day-old broilers were randomly assigned to one of five dietary treatments, with six replicates each, for 35 days. Dietary treatments were: 1) non-challenged, non-treated (NC); 2) challenged, non-treated (PC); 3) PC+ Salinomycin (0.05 g/kg; AB); 4) PC+THB (0.1 g/kg; THB); and 5) PC+THB+OE (0.1 g/kg; COM). On day 14, all groups except for NC were challenged with a 10-fold dose of Livacox® T anticoccidial vaccine to induce mild coccidiosis. All treatments significantly improved (P<0.05) body weight, average daily gain, and average daily feed intake, compared to PC, on days 21, 28, and 35. However, all treatments significantly reduced (P<0.05) the feed conversion ratio of PC by more than 14.60% on day 35, 11.76% during growing period, and 10.36% through the entire period. Broilers receiving anticoccidial treatments had 54.23% and 51.86% lower lesion scores (P<0.05) at 4 and 7 days post-infection, respectively, compared to PC. Additionally, the villus height of COM was significantly longer (P < 0.05) than that of THB. Although the molecular action of COM remains unclear, OE addition to THB reduced the shedding of oocysts better than THB alone (P<0.05, 9-11 days post-infection). Most importantly, COM effectively minimized the mortality of challenged birds from as high as 11.90% (PC) to 0%, a level similar to NC and AB, while THB maintained a mortality of 2.38%. In conclusion, the anticoccidial effect of THB can be enhanced by the addition of OE for better animal performance and the elimination of deleterious effects from coccidiosis-infected broilers for 35 days.

10.
Semin Cell Dev Biol ; 121: 161-170, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33992531

RESUMEN

The mammalian genome is highly packed into the nucleus. Over the past decade, the development of Hi-C has contributed significantly to our understanding of the three-dimensional (3D) chromatin structure, uncovering the principles and functions of higher-order chromatin organizations. Recent studies have repositioned its property in spatial proximity measurement to address challenging problems in genome analyses including genome assembly, haplotype phasing, and the detection of genomic rearrangements. In particular, the power of Hi-C in detecting large-scale structural variations (SVs) in the cancer genome has been demonstrated, which is challenging to be addressed solely with short-read-based whole-genome sequencing analyses. In this review, we first provide a comprehensive view of Hi-C as an intuitive and effective SV detection tool. Then, we introduce recently developed bioinformatics tools utilizing Hi-C to investigate genomic rearrangements. Finally, we discuss the potential application of single-cell Hi-C to address the heterogeneity of genomic rearrangements and sub-population identification in the cancer genome.


Asunto(s)
Cromatina/metabolismo , Biología Computacional/métodos , Genómica/métodos , Humanos
11.
Gut Liver ; 15(6): 851-857, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-33833134

RESUMEN

Background/Aims: : Recently, the treatment of Crohn's disease (CD) has changed to a treat-to-target strategy, in which disease progression is prevented with early intervention. We analyzed the long-term evolution of nonstricturing, nonpenetrating (B1) disease at diagnosis and factors related to disease evolution in pediatric CD. Methods: We retrospectively analyzed 402 patients between 2000 and 2013 who were younger than 18 years and had B1 disease at CD diagnosis. The median follow-up was 6.1 years (range, 1 to 13 years). The cumulative probabilities of developing stricturing (B2) or penetrating (B3) disease and associations between risk factors and disease behavior evolution were evaluated. Results: Among the 402 patients, 75 (18.7%) had B2 or B3 disease by the final follow-up. The cumulative probabilities of disease behavior evolution were 18.3%, 34.3%, and 50.9% at 5, 10, and 13 years, respectively. Patients whose disease progressed had an increased risk of intestinal resection (hazard ratio [HR], 3.61; 95% confidence interval [CI], 2.25 to 6.03; p<0.001). First-degree family history of inflammatory bowel disease (HR, 2.38; 95% CI, 1.07 to 5.28; p=0.032), isolated ileal involvement at diagnosis (HR, 7.55; 95% CI, 1.04 to 15.57; p=0.045), and positive anti-Saccharomyces cerevisiae antibody titers (HR, 2.10; 95% CI, 1.03 to 4.25; p=0.040) were associated with disease behavior evolution. Early treatment with biologics significantly reduced disease progression (HR, 0.46; 95% CI, 0.79 to 3.39; p=0.042). Conclusions: This study suggests that early aggressive therapy should be considered in B1 behavior pediatric CD patients with risk factors of disease evolution to improve long-term outcomes.


Asunto(s)
Productos Biológicos , Enfermedad de Crohn , Productos Biológicos/uso terapéutico , Niño , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/tratamiento farmacológico , Progresión de la Enfermedad , Humanos , República de Corea , Estudios Retrospectivos , Factores de Riesgo
12.
Nature ; 588(7839): 664-669, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33328632

RESUMEN

Current organoid models are limited by their inability to mimic mature organ architecture and associated tissue microenvironments1,2. Here we create multilayer bladder 'assembloids' by reconstituting tissue stem cells with stromal components to represent an organized architecture with an epithelium surrounding stroma and an outer muscle layer. These assembloids exhibit characteristics of mature adult bladders in cell composition and gene expression at the single-cell transcriptome level, and recapitulate in vivo tissue dynamics of regenerative responses to injury. We also develop malignant counterpart tumour assembloids to recapitulate the in vivo pathophysiological features of urothelial carcinoma. Using the genetically manipulated tumour-assembloid platform, we identify tumoural FOXA1, induced by stromal bone morphogenetic protein (BMP), as a master pioneer factor that drives enhancer reprogramming for the determination of tumour phenotype, suggesting the importance of the FOXA1-BMP-hedgehog signalling feedback axis between tumour and stroma in the control of tumour plasticity.


Asunto(s)
Organoides/patología , Organoides/fisiología , Regeneración , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/fisiopatología , Vejiga Urinaria/patología , Vejiga Urinaria/fisiología , Adulto , Animales , Proteínas Morfogenéticas Óseas/metabolismo , Femenino , Erizos/metabolismo , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Organoides/fisiopatología , Análisis de la Célula Individual , Células Madre/citología , Células Madre/patología , Células Madre/fisiología , Transcriptoma , Vejiga Urinaria/citología , Infecciones Urinarias/metabolismo , Infecciones Urinarias/patología
13.
J Vis Exp ; (155)2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-32065155

RESUMEN

The development of advanced tumor models has long been encouraged because current cancer models have shown limitations such as lack of three-dimensional (3D) tumor architecture and low relevance to human cancer. Researchers have recently developed a 3D in vitro cancer model referred to as tumor organoids that can mimic the characteristics of a native tumor in a culture dish. Here, experimental procedures are described in detail for the establishment of bladder tumor organoids from a carcinogen-induced murine bladder tumor, including culture, passage, and maintenance of the resulting 3D tumor organoids in vitro. In addition, protocols to manipulate the established bladder tumor organoid lines for genetic engineering using lentivirus-mediated transduction are described, including optimized conditions for the efficient introduction of new genetic elements into tumor organoids. Finally, the procedure for orthotopic transplantation of bladder tumor organoids into the wall of the murine bladder for further analysis is laid out. The methods described in this article can facilitate the establishment of an in vitro model for bladder cancer for the development of better therapeutic options.


Asunto(s)
Organoides/trasplante , Neoplasias de la Vejiga Urinaria/terapia , Animales , Modelos Animales de Enfermedad , Ratones , Organoides/fisiología
14.
Elife ; 82019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31036156

RESUMEN

In bladder, loss of mammalian Sonic Hedgehog (Shh) accompanies progression to invasive urothelial carcinoma, but the molecular mechanisms underlying this cancer-initiating event are poorly defined. Here, we show that loss of Shh results from hypermethylation of the CpG shore of the Shh gene, and that inhibition of DNA methylation increases Shh expression to halt the initiation of murine urothelial carcinoma at the early stage of progression. In full-fledged tumors, pharmacologic augmentation of Hedgehog (Hh) pathway activity impedes tumor growth, and this cancer-restraining effect of Hh signaling is mediated by the stromal response to Shh signals, which stimulates subtype conversion of basal to luminal-like urothelial carcinoma. Our findings thus provide a basis to develop subtype-specific strategies for the management of human bladder cancer.


Asunto(s)
Epigénesis Genética , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Erizos/genética , Transducción de Señal/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Metilación de ADN , Modelos Animales de Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Persona de Mediana Edad , Células del Estroma/metabolismo , Células del Estroma/patología , Análisis de Supervivencia , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/patología
15.
Org Biomol Chem ; 17(13): 3319-3323, 2019 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-30869722

RESUMEN

Electrochemical oxidative radical trifluoromethylation/semipinacol rearrangement sequences of alkenyl alcohols were developed in this study. This approach is environmentally benign and uses the shelf-stable Langlois reagent as a trifluoromethyl radical precursor and electrons as the oxidizing reagents. The present protocol offers a facile route to prepare ß-trifluoromethylated ketone derivatives.

16.
Water Res ; 132: 23-33, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29304445

RESUMEN

In this study, a detailed rigorous theoretical model was developed to predict the transmembrane flux of a shell-and-tube type vacuum membrane distillation (VMD) module for seawater desalination. Two modes of operation are used for performing the VMD, namely lumen-side feed (in-out) configuration and shell-side feed (out-in) configuration. In this study, detailed mathematical formulations are derived for an out-in configuration that is commonly used in seawater desalination applications. Experimental results and model predictions for mean permeate flux are compared and shown to be in good agreement. The results indicate that although the simple VMD model that maintains a constant permeate pressure is easy to use, it is likely to significantly overestimate the mean permeate flux when compared to the detailed model that considers the pressure build-up in the fiber lumen. The pressure build-up of water vapor in the fiber lumen is identified as the crucial factor that significantly affects the VMD performance because it directly reduces the driving force for vapor permeation through the membrane pores. Additionally, its effect is more pronounced at longer fiber lengths and higher permeate fluxes, and this is achieved at higher feed temperatures and velocities and at lower feed salinities. In conclusion, the results of the study are extremely important in module design for the practical applications of VMD processes.


Asunto(s)
Destilación/métodos , Modelos Teóricos , Purificación del Agua/métodos , Simulación por Computador , Destilación/instrumentación , Membranas Artificiales , Presión , Salinidad , Agua de Mar , Vapor , Vacio , Purificación del Agua/instrumentación
17.
Beilstein J Org Chem ; 12: 1551-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27559405

RESUMEN

Chiral binaphthyl-modified squaramide-catalyzed enantioselective addition of diphenyl phosphonate to ketimines derived from isatins has been achieved. This method affords practical and efficient access to chiral 3-amino-3-phosphonyl-substituted oxindole derivatives in high yields with excellent enantioselectivities (up to 99% ee).

18.
Lab Chip ; 16(17): 3268-75, 2016 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-27416810

RESUMEN

In this paper, we present a fully integrated and automated lab-on-a-disc for the rapid determination of the total phenolic content (TPC) and antioxidant activity (AA) of beverage samples. The simultaneous determinations of TPC and AA on a spinning disc were achieved by integrating three independent analytical techniques: the Folin-Ciocalteu method that is used to measure TPC, the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) method and the ferric reducing antioxidant power method that are used to measure AA. The TPC and AA of 8 different beverage samples, including various fruit juices, tea, wine and beer, were analyzed. Unlike conventional labor-intensive processes for measuring TPC and AA, our fully automated platform offers one-step operation and rapid analysis.


Asunto(s)
Antioxidantes/análisis , Bebidas/análisis , Análisis de los Alimentos/instrumentación , Dispositivos Laboratorio en un Chip , Fenoles/análisis , Automatización de Laboratorios/instrumentación , Compuestos de Bifenilo/química , Diseño de Equipo , Compuestos Férricos/química , Humanos , Indicadores y Reactivos/química , Molibdeno/química , Oxidación-Reducción , Picratos/química , Reproducibilidad de los Resultados , Compuestos de Tungsteno/química
19.
J Vis Exp ; (110)2016 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-27167836

RESUMEN

Enzyme-linked immunosorbent assay (ELISA) is a promising method to detect small amount of proteins in biological samples. The devices providing a platform for reduced sample volume and assay time as well as full automation are required for potential use in point-of-care-diagnostics. Recently, we have demonstrated ultrasensitive detection of serum proteins, C-reactive protein (CRP) and cardiac troponin I (cTnI), utilizing a lab-on-a-disc composed of TiO2 nanofibrous (NF) mats. It showed a large dynamic range with femto molar (fM) detection sensitivity, from a small volume of whole blood in 30 min. The device consists of several components for blood separation, metering, mixing, and washing that are automated for improved sensitivity from low sample volumes. Here, in the video demonstration, we show the experimental protocols and know-how for the fabrication of NFs as well as the disc, their integration and the operation in the following order: processes for preparing TiO2 NF mat; transfer-printing of TiO2 NF mat onto the disc; surface modification for immune-reactions, disc assembly and operation; on-disc detection and representative results for immunoassay. Use of this device enables multiplexed analysis with minimal consumption of samples and reagents. Given the advantages, the device should find use in a wide variety of applications, and prove beneficial in facilitating the analysis of low abundant proteins.


Asunto(s)
Proteína C-Reactiva/aislamiento & purificación , Técnicas Analíticas Microfluídicas/métodos , Troponina I/aislamiento & purificación , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Ensayo de Inmunoadsorción Enzimática/métodos , Dispositivos Laboratorio en un Chip , Técnicas Analíticas Microfluídicas/instrumentación , Troponina I/sangre
20.
Anal Chem ; 87(15): 7865-71, 2015 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-26121222

RESUMEN

We have developed a fully integrated centrifugal microfluidic device for rapid on-site quantification of lipids from microalgal samples. The fully automated serial process involving cell sedimentation and lysis, liquid-liquid extraction, and colorimetric detection of lipid contents was accomplished within 13 min using a lab-on-a-disc. The presented organic solvent-tolerable (for n-hexane, ethanol) microfluidic disc was newly fabricated by combining thermal fusion bonding and carbon dot-based valving techniques. It is expected that this novel platform will possibly contribute toward sustainable biofuel applications by providing a practical solution for on-site monitoring of lipid accumulation in microalgal samples, thus providing imperative contribution toward energy and environmental purposes of centrifugal microfluidic technology.


Asunto(s)
Lípidos/análisis , Microalgas/química , Técnicas Analíticas Microfluídicas/instrumentación , Automatización , Colorimetría , Factores de Tiempo
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