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With alkyl halides (I, Br, Cl) as a coupling partner, an electrochemically driven strategy for para-selective C(sp2)-H alkylation of electron-deficient arenes (aryl esters, aldehydes, nitriles, and ketones) has been achieved to access diverse alkylated arenes in one step. The reaction enables the activation of alkyl halides in the absence of sacrificial anodes, achieving the formation of C(sp2)-C(sp3) bonds under mild electrolytic conditions. The utility of this protocol is reflected in high site selectivity, broad substrate scope, and scalable.
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PURPOSE: Extradomain B of fibronectin (EDB-FN) is a promising diagnostic and therapeutic biomarker for thyroid cancer (TC). Here, we identified a high-affinity EDB-FN targeted peptide named EDBp (AVRTSAD) and developed three EDBp-based probes, Cy5-PEG4-EDBp(Cy5-EDBp), [18F]-NOTA-PEG4-EDBp([18F]-EDBp), and [177Lu]-DOTA-PEG4-EDBp ([177Lu]-EDBp), for the surgical navigation, radionuclide imaging, and therapy of TC. METHODS: Based on the previously identified EDB-FN targeted peptide ZD2, the optimized EDB-FN targeted peptide EDBp was identified by using the alanine scan strategy. Three EDBp-based probes, Cy5-EDBp, [18F]-EDBp, and [177Lu]-EDBp, were developed for fluorescence imaging, positron emission tomography (PET) imaging, and radiotherapy in TC tumor-bearing mice, respectively. Additionally, [18F]-EDBp was evaluated in two TC patients. RESULTS: The binding affinity of EDBp to the EDB fragment protein (Kd = 14.4 ± 1.4 nM, n = 3) was approximately 336-fold greater than that of the ZD2 (Kd = 4839.7 ± 361.7 nM, n = 3). Fluorescence imaging with Cy5-EDBp facilitated the complete removal of TC tumors. [18F]-EDBp PET imaging clearly delineated TC tumors, with high tumor uptake (16.43 ± 1.008%ID/g, n = 6, at 1-h postinjection). Radiotherapy with [177Lu]-EDBp inhibited tumor growth and prolonged survival in TC tumor-bearing mice (survival time of different treatment groups: saline vs. EDBp vs. ABRAXANE vs. [177Lu]-EDBp = 8.00 d vs. 8.00 d vs. 11.67 d vs. 22.33 d, ***p < 0.001). Importantly, the first-in-human evaluation of [18F]-EDBp demonstrated that it had specific targeting properties (SUVmax value of 3.6) and safety. CONCLUSION: Cy5-EDBp, [18F]-EDBp, and [177Lu]-EDBp are promising candidates for the surgical navigation, radionuclide imaging, and radionuclide therapy of TC, respectively.
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Cirurgia Assistida por Computador , Neoplasias da Glândula Tireoide , Humanos , Animais , Camundongos , Fibronectinas/metabolismo , Tomografia por Emissão de Pósitrons , Peptídeos , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/terapia , Linhagem Celular TumoralRESUMO
OBJECTIVE: To evaluate the interaction effects of Polycyclic aromatic hydrocarbons (PAHs) exposure and variants in cGAS-STING genes on mitochondrial DNA copy number (mtDNAcn) in workers. METHODS: The mtDNAcn was determined by real-time quantitative polymerase-chain reaction in 544 PAHs-exposed workers and 238 office workers. The polymorphisms were detected by flight mass spectrometry. RESULTS: The mtDNAcn in PAHs exposure group was significantly lower than non-occupational exposure population (P < 0.00). The cGAS rs610913 CA+AA had significant interaction effects with STING rs11554776 GG+GA (P = 0.035), rs7380824 CC+CT (P = 0.026), and rs78233829 GC+CC (P = 0.034) on mtDNAcn. The generalized linear model results showed that the influencing factors of mtDNAcn include PAHs exposure (P < 0.001) and the interaction of PAHs exposure and cGAS rs 311678 AA+AG (P = 0.047). CONCLUSION: The influencing factors of mtDNAcn include PAHs exposure and the interaction of PAHs exposure and cGAS rs 311678 AA+AG.
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Coque , Proteínas de Membrana , Nucleotidiltransferases , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Coque/efeitos adversos , Variações do Número de Cópias de DNA , DNA Mitocondrial/genética , Nucleotidiltransferases/genética , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Proteínas de Membrana/genética , Exposição Ocupacional/efeitos adversosRESUMO
Chiral hybrid perovskites (CHPs), aggregating chirality and favorable semiconducting properties in one, have taken a prominent position in direct circularly polarized light detection (CPL). However, passive high circular polarization sensitivity (gres) photodetection in CHPs is still elusive and challenging. Benefitting from efficient control and turning of carrier transport of CHPs by dimensional engineering, here, we unprecedentedly proposed a chain-to-layer dimensionality engineering to realize high-gres passive photodetection. Two novel 2D layered CHPs (R/S-PPA)EAPbBr4 (2R/2S) (PPA = 1-phenylpropylamine, EA = ethylammonium) are successfully synthesized by alloying an EA cation with small steric hindrance into the chained CHPs (R/S-PPA)PbBr3 (1R/1S). Particularly, compared with the neglectable photoresponse in 1R, the obtained 2R by chain-to-layer dimensionality engineering gives rise to an excellent photoconductivity and robust polar photovoltage effect (PPE) with a giant open-circuit voltage of 2.5 V. Furthermore, such PPE promotes realizing an impressive gres in 2R up to 0.42 at zero bias because of the independent separation of photoexcited carriers, which is the highest value among the reported layered chiral perovskites. This work paves the way for the vigorous development of higher dimensional CHPs and will reveal their applications in the field of passive high-gres CPL detection.
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An efficient anodic C(sp3)-H acyloxylation protocol has been established via intermolecular cross-dehydrogenative C(sp3)-O coupling. The protocol provides various C2-acyloxy indolin-3-ones without the addition of metal catalysts and external oxidants because indolin-3-ones can be directly oxidized at the anode. The effective application of several medical drugs and the realization of the gram-scale experiment have proven the practicality of this protocol.
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Oxidantes , Catálise , Eletrodos , Estrutura Molecular , OxirreduçãoRESUMO
A metal-free visible-light-driven cascade cyclization reaction to synthesize 3-methyl-3-acetophenone-2-oxindoles and 3-methyl-3-(methylsulfonyl)benzene-2-oxindoles in yields up to 96% and 99%, via benzoyl and phenylsulfinyl radicals with acrylamide derivatives is reported, respectively. Extensive studies, including gram-scale, radical capture and isotope experiments, were performed to indicate that the reaction may involve a radical process.
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Acrilamida , Benzeno , Ciclização , Oxindóis , Indóis , Metais , AcetofenonasRESUMO
AIMS: Arrhythmogenic cardiomyopathy (ACM) is characterized by progressive loss of cardiomyocytes, and fibrofatty tissue replacement. Extracellular vesicles (EVs) secreted by cardiosphere-derived cells, immortalized, and engineered to express high levels of ß-catenin, exert anti-inflammatory, and anti-fibrotic effects. The aim of the current study was to assess efficacy of EVs in an ACM murine model. METHODS AND RESULTS: Four-week-old homozygous knock-in mutant desmoglein-2 (Dsg2mt/mt) were randomized to receive weekly EVs or vehicle for 4 weeks. After 4 weeks, DSG2mt/mt mice receiving EVs showed improved biventricular function (left, P < 0.0001; right, P = 0.0037) and less left ventricular dilation (P < 0.0179). Electrocardiography revealed abbreviated QRS duration (P = 0.0003) and QTc interval (P = 0.0006) in EV-treated DSG2mt/mt mice. Further electrophysiology testing in the EV group showed decreased burden (P = 0.0042) and inducibility of ventricular arrhythmias (P = 0.0037). Optical mapping demonstrated accelerated repolarization (P = 0.0290) and faster conduction (P = 0.0274) in Dsg2mt/mt mice receiving EVs. DSG2mt/mt hearts exhibited reduced fibrosis, less cell death, and preserved connexin 43 expression after EV treatment. Hearts of Dsg2mt/mt mice expressed markedly increased levels of inflammatory cytokines that were, in part, attenuated by EV therapy. The pan-inflammatory transcription factor nuclear factor-κB (NF-κB), the inflammasome sensor NLRP3, and the macrophage marker CD68 were all reduced in EV-treated animals. Blocking EV hsa-miR-4488 in vitro and in vivo reactivates NF-κB and blunts the beneficial effects of EVs. CONCLUSIONS: Extracellular vesicle treatment improved cardiac function, reduced cardiac inflammation, and suppressed arrhythmogenesis in ACM. Further studies are needed prior to translating the present findings to human forms of this heterogenous disease.
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Cardiomiopatias , Vesículas Extracelulares , Animais , Arritmias Cardíacas , Desmogleínas , Camundongos , Miócitos CardíacosRESUMO
The ligand-regulated regiodivergent hydroarylation of the distal double bond of allenamides with aryl boronic acid was achieved in the presence of palladium(II) catalysts, delivering a variety of functionalized enamide with excellent E selectivity and Markovnikov/anti-Markovnikov selectivity. Two possible coordination intermediates were proposed to be responsible for the regiodivergent hydroarylation: (1) The coordination Intermediate I, which was proposed to be formed through the coordination of MeCN, distal double bond, phenyl to palladium, led to the aryl group away from the Intermediate I, inducing excellent E selectivity and anti-Markovnikov selectivity. (2) A switch of regioselectivity to 1,2-Markovnikov hydroarylation was obtained using bidentate phosphine ligand (dppf or Xantphos). The formed coordination Intermediate II led to the N-tether away from the Intermediate II and at the trans position of aryl, resulting in excellent E selectivity and Markovnikov selectivity. Meanwhile, tentative investigation on the mechanism proved that the hydron source of this hydroarylation is more likely to be boronic acid. The transmetallation between aryl boronic acid and palladium catalyst was the initial step of this transformation.
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The aim of this study was to assess the association between NF1 and PTEN gene polymorphisms and the risk of soft tissue sarcomas (STSs). This case-control study collected peripheral blood from 136 patients with STSs and 124 healthy controls. Six single nucleotide polymorphisms (SNPs) of the NF1 gene and five SNPs of the PTEN gene were investigated and genotyped using the SNaPshot assay. The association between the polymorphisms and the risk of STSs was estimated using unconditional logistic regression analysis. The results showed that individuals with the TC/CC genotype for NF1 rs2905789 displayed a significantly increased risk of STSs compared with individuals with wild-type TT (OR = 1.702, 95% CI = 1.002-2.890, P = 0.049). There were no significant differences in the distribution of the genotype or the allele frequencies of the polymorphisms of the NF1 and PTEN genes between the STSs patients and the controls in a Chinese population. Therefore, this study's results suggest that individuals carrying the TC/CC genotype for NF1 rs2905789 may be susceptible to STSs.
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Povo Asiático/genética , Biomarcadores Tumorais/genética , Predisposição Genética para Doença , Neurofibromina 1/genética , PTEN Fosfo-Hidrolase/genética , Polimorfismo de Nucleotídeo Único , Sarcoma/epidemiologia , Adulto , Estudos de Casos e Controles , China/epidemiologia , Feminino , Seguimentos , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Sarcoma/genética , Sarcoma/patologiaRESUMO
BACKGROUND: The aim of this study was to investigate the association between insulin resistance (IR) and vascular cognitive impairment (VCI) in patients with cerebral small vessel disease (CSVD). METHODS: A total of 275 CSVD patients were enrolled in this retrospective case-control study. The homeostatic model assessment of insulin resistance (HOMA-IR) was used to measure the index of insulin resistance. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Spearman's correlation coefficient was used to evaluate the correlation between HOMA-IR and MoCA score. The variance inflation factor (VIF) was used to detect collinearity between variables. Multivariate logistic regression analysis was employed to confirm whether HOMA-IR is an independent risk factor for VCI in CVSD. Finally, receiver operating characteristic (ROC) curve analysis was conducted to assess the diagnostic value of HOMA-IR in VCI. RESULTS: Of the 275 patients, 164 displayed VCI. VCI patients showed a significantly higher level of HOMA-IR compared to non-VCI patients (P < 0.001). HOMA-IR was negatively correlated with the MoCA score (r = -0.593, P < 0.001). After adjusting for potential confounding variables, using HOMA-IR quartile 1 (<1.11) as the reference, HOMA-IR quartile 3 (1.71-2.50) and quartile 4 (≥2.50) were independently associated with the occurrence of VCI; for each one unit increase in the HOMA-IR, the risk of VCI increased by 177.3% (odds ratio 2.773, 95% confidence interval: 1.050-7.324, P = 0.040) and 444.3% (odds ratio 5.443, 95% confidence interval: 2.109-14.050, P < 0.001), respectively. According to the ROC curve, the optimal cut-off point of HOMA-IR in predicting VCI was 1.55, and the area under the curve was 0.744, with a sensitivity of 71.3% and a specificity of 69.4%. CONCLUSION: This study demonstrated that increased IR is significantly associated with VCI in CSVD patients.
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Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Resistência à Insulina , Estudos de Casos e Controles , Doenças de Pequenos Vasos Cerebrais/complicações , China/epidemiologia , Disfunção Cognitiva/diagnóstico , Humanos , Estudos RetrospectivosRESUMO
BACKGROUND: We attempted to train and validate a model of deep learning for the preoperative prediction of the response of patients with intermediate-stage hepatocellular carcinoma (HCC) undergoing transarterial chemoembolization (TACE). METHOD: All computed tomography (CT) images were acquired for 562 patients from the Nan Fang Hospital (NFH), 89 patients from Zhu Hai Hospital Affiliated with Jinan University (ZHHAJU), and 138 patients from the Sun Yat-sen University Cancer Center (SYUCC). We built a predictive model from the outputs using the transfer learning techniques of a residual convolutional neural network (ResNet50). The prediction accuracy for each patch was revaluated in two independent validation cohorts. RESULTS: In the training set (NFH), the deep learning model had an accuracy of 84.3% and areas under curves (AUCs) of 0.97, 0.96, 0.95, and 0.96 for complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD), respectively. In the other two validation sets (ZHHAJU and SYUCC), the deep learning model had accuracies of 85.1% and 82.8% for CR, PR, SD, and PD. The ResNet50 model also had high AUCs for predicting the objective response of TACE therapy in patches and patients of three cohorts. Decision curve analysis (DCA) showed that the ResNet50 model had a high net benefit in the two validation cohorts. CONCLUSION: The deep learning model presented a good performance for predicting the response of TACE therapy and could help clinicians in better screening patients with HCC who can benefit from the interventional treatment. KEY POINTS: ⢠Therapy response of TACE can be predicted by a deep learning model based on CT images. ⢠The probability value from a trained or validation deep learning model showed significant correlation with different therapy responses. ⢠Further improvement is necessary before clinical utilization.
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Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Aprendizado Profundo , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Tomografia Computadorizada por Raios X , Carcinoma Hepatocelular/patologia , Progressão da Doença , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The pandemic diseases caused by SARS-CoV-2 are now threatening human health and survival. Early diagnosis and isolation of mild or asymptomatic COVID-19 patients is important to control the spread of SARS-CoV-2. In this study, we investigate the potential clinical utility of lymphocyte CPD for early diagnosis of COVID-19. To investigate the potential of lymphocyte cell population data (lymphocyte CPD) for use in early diagnosis of coronavirus disease 2019 (COVID-19). Lymphocyte CPD of healthy control (n = 51), common cold patients (n = 49) and mild COVID-19 patients (n = 126) were generated using hematology analyzer. The parameters were subjected to sensitivity and specificity analysis to determine their suitability as biomarkers for early diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Normality analysis showed that lymphocyte CPD followed a normal distribution. There were no significant differences in white blood cells (WBC) and lymphocyte (LY#) counts as well as the neutrophil-to-lymphocyte ratio (NLR) among the groups (p > 0.05). Lymphocyte volume standard deviation (LV-SD), lymphocyte conductivity standard deviation (LC-SD) and lymphocyte light scatter standard deviation (LS-SD) were significantly higher in the COVID-19 group than in common cold and control groups (p < 0.05). The corresponding mean lymphocyte light scattering (MLS) was significantly reduced in the COVID-19 group, relative to the common cold group, but was significantly increased, when compared with the control group (p < 0.05). Moreover, there was no significant difference in mean lymphocyte volume (MLV) between the COVID-19 group and the common cold or control group (p > 0.05), but it was significantly higher in the common cold group than in the control group (p < 0.05). At a cutoff value ≥ 16.38, LS-SD was more sensitive and specific than other lymphocyte CPD parameters. At a cutoff value ≥ 11.89, LC-SD achieved 84.4 % sensitivity, 87.5 % specificity, and an area under the curve (AUC) of 0.888. However, at a cutoff value ≥ 15.95, LS-SD reached 81.3 % sensitivity, 75 % specificity and an AUC of 0.876. These results suggest that lymphocyte CPD parameters have great diagnostic potential for SARS-CoV-2 infection and can be used for early diagnosis of the disease.
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COVID-19/diagnóstico , Contagem de Linfócitos , Adulto , COVID-19/sangue , COVID-19/patologia , Tamanho Celular , Diagnóstico Precoce , Feminino , Humanos , Linfócitos/citologia , Linfócitos/patologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2/isolamento & purificação , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Hypertension and hyperhomocysteinemia (HHcy) are independent risk factors of stroke and are associated with each other. Although evidence suggests that they are related to cognitive impairment, the relationship between hypertension accompanied with HHcy and poststroke cognitive impairment (PSCI) is unclear. OBJECTIVE: To define the relationship between hypertension with HHcy and early cognitive impairment after acute cerebral infarction. MATERIALS AND METHODS: Our study enrolled 232 patients with acute first-ever ischemic stroke. Patients were assigned to 3 groups by blood pressure and homocysteine (Hcy) levels: hypertension with HHcy, simple hypertension, or control. Cognition was assessed by the Montreal cognitive assessment at admission and at 3- and 6-month follow-ups. RESULTS: The hypertension with HHcy group exhibited the highest incidence of early cognitive impairment (simple hypertension: p = 0.000; control: p = 0.000). This group also had lower visual space/executive scores than the simple hypertension group (p = 0.000) and lower delayed recall scores than the control group (p = 0.011). Multivariate analysis showed that hypertension with HHcy (OR 7.797; 95% CI 2.917-20.843; p = 0.000), the level of serum Hcy (OR 1.063; 95% CI 1.109-1.109; p = 0.005), education years (OR 0.797; 95% CI 0.722-0.880; p = 0.000), and Fazekas scale of leukoaraiosis (OR 1.648; 95% CI 1.239-2.191; p = 0.001) were independent influencing factors of early PSCI; however, simple hypertension (OR 1.183, 95% CI 0.208-6.737; p = 0.850) and simple HHcy (OR 1.112, 95% CI 0.181-6.810; p = 0.909) were not. CONCLUSION: Patients with both hypertension and HHcy are at an increased risk of early cognitive impairment after acute first-ever ischemic stroke.
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Disfunção Cognitiva/etiologia , Hiper-Homocisteinemia/complicações , Hipertensão/complicações , Acidente Vascular Cerebral/complicações , Idoso , Isquemia Encefálica/complicações , Disfunção Cognitiva/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de RiscoRESUMO
BACKGROUND: The effectiveness of active pharmacovigilance depends on the specific methods adopted and the work patterns put into place. Over the past few years, much attention has been paid to the importance of implementing such systems in China. However, less has been done to evaluate the state of implementation and future needs of such systems. METHODS: This paper reviews China's recent approaches to active pharmacovigilance by examining: (1) information collected from scientific articles and the websites of the China Food and Drug Administration and the China National Center for Adverse Drug Reaction Monitoring, (2) information available on China's spontaneous reporting systems (SRS) and active pharmacovigilance system, and (3) annual reports and internal reports on this subject. RESULTS: Areas that improved most meaningfully for China's active pharmacovigilance in recent years appear to include: (1) quicker reporting and more intelligent scanning methods for adverse drug reactions (ADRs), (2) the use of pharmacovigilance approaches to mine electronic hospital records, and (3) the development of integrated systems including the China Hospital Pharmacovigilance System and China Sentinel Hospital Alliance Program. CONCLUSION: Not only has the national online SRS system provided a platform for passive pharmacovigilance, it has also become an important platform for various explorations of active pharmacovigilance in China. Quick reporting and intelligent scanning of ADRs, facilitated by automated ADR detection based on electronic hospital records, have accelerated to capabilities for active pharmacovigilance. The outcomes of the programs, such as the China Hospital Pharmacovigilance System and China Sentinel Hospital Alliance Program, usher in a new era for China's active pharmacovigilance. These are particularly important to bridge the information system of sentinel hospitals and ADR research centers, but gaps remain. Thus, much work needs to be done before a high-level active pharmacovigilance system is sufficiently mature to ensure drug safety in the country.
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Sistemas de Notificação de Reações Adversas a Medicamentos , Farmacovigilância , China , Sistemas de Informação Hospitalar , HumanosRESUMO
Author: The present work, involving the formation of NO and nitrous acid (HONO) and the nitration of polycyclic aromatic hydrocarbon (PAHs) to nitro-PAHs as well as the uptake coefficients of NO2, has been performed on a normal-pressure flow reactor to identify the nitration products during the heterogeneous reaction of soot toward NO2 in the dark and under simulated sunlight. Two types of soot particles, namely the commercial black carbon (BC) and the diesel engine soot (ES), were selected as the studied soot to compare the impacts of soot properties on heterogeneous nitration. During the whole reaction on either of the two studied soots in the dark, a fast reversible physical adsorption is observed at the very beginning, followed by a slow irreversible chemical conversion from NO2 to HONO and NO, in good agreement with the "reduction-oxidation" mechanism. HONO is the most abundant product during the nitration reaction on the two studied soots, contributing to 70-90% of consumed NO2 after 50 min exposure. Reaction orders of NO2 for HONO are determined as 1.20 ± 0.07 and 1.31 ± 0.04 for BC and ES, respectively, which are both close to first-order. Moreover, four sorts of PAHs compounds and their five nitro-derivatives have been identified and quantified during the reaction. About 40% and 20% of the total four measured PAHs are consumed on BC and ES, respectively, resulting in an increase in the total five measured nitro-PAHs by 21-fold on BC and 2.8-fold on ES. Finally, the impacts of light on gaseous and organics products have been investigated and the results confirm that simulated sunlight can enhance the reactivity of PAHs toward NO2 and cause the photolysis of newly formed nitro-compounds with more HONO formation, strongly suggesting that photochemistry of soot in the presence of NO2 is of great importance to be a photochemical source of HONO and would also influence the fates of PAHs and nitro-PAHs on soot.
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To better use the phase information to compensate the influence of blood flow, the phase unwrapping problem in susceptibility weighted imaging (SWI) is studied in this paper. In order to improve the accuracy of unwrapping, this paper proposes a magnitude image-guided phase unwrapping algorithm of SWI. The basic idea is as follows: (1) reduce the influence of noise by improving the rotational invariant non-local principal component analysis method (PRI-NL-PCA); (2) extract the corresponding solid region in the phase image to avoid the influence of the background noise on the phase unwrapping method; (3) use the phase compensation method to constrain the phase image reconstructed by the K-space. Finally, the reliability of the unwrapping method is evaluated by using four kinds of statistics as quantification index: the number, mean (M), variance (Var), and positive percentage (Pos) and negative percentage (Neg) of phasic error points. By comparing the simulated data with 226 sets of true head SWI data, the results show that the proposed algorithm has high accuracy compared with the classical branch cut method and the least squares method.
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The generation of α-imino gold carbenes via gold-catalyzed intermolecular reaction of azides and ynamides is disclosed. This new methodology allows for highly regioselective access to valuable 2-aminoindoles and 3-amino-ß-carbolines in generally good to excellent yields. A mechanistic rationale for this tandem reaction, especially for the observed high regioselectivity, is supported by DFT calculations.
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Although there have been a number of publications focused on heterogeneous of NO2 on mineral particles, most of these studies were focused on ß-Al2O3 and performed in the dark. Less was known about the reaction process of NO2 on α-Al2O3, especially the effect of sunlight factor. The heterogeneous reaction between NO2 and α-Al2O3 was investigated by using diffuse reflectance infrared Fourier transform spectrometry. The effects of NO2 and O2 concentrations as well as simulated sunlight were examined, and the reaction mechanism including the consumption of surface OH groups, oxidation process of nitrites, and the formation of water was also discussed in detail. It was observed that the formation rates of nitrates and nitrites were sensitive to NO2 concentrations and O2 concentrations. Nitrite was identified to be an intermediate production and disappeared very soon as [NO2] was up to 4.035 × 10(15) molecules/cm(3). Light played an important role in the changes of the electronic configuration of mineral dust, such as electronic donating ability, surface OH groups orientation, as well as the conversion efficiency between proton acid and nonproton acid, all of which could significantly enhance the heterogeneous reaction process. The reaction order for NO2 and O2 was determined to be 0.960 ± 0.111 and 0.620 ± 0.028, respectively. The uptake coefficient of NO2, which dominated the first step of the heterogeneous reaction, was calculated by the infrared absorbance with the use of ion chromatography and determined to be 9.9 × 10(-10) in the dark and varied from 2.54 to 3.33 × 10(-9) under simulated sunlight from 0.45 to 1.35 mW/cm(2). It was also found that γNO2 was independent of [NO2] and sunlight increased the uptake coefficient by three times, indicating that the heterogeneous reaction between NO2 and α-Al2O3 was enhanced under sunlight.
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For sequencing-based spatial transcriptomics data, the gene-spot count matrix is highly sparse. This feature is similar to scRNA-seq. The goal of this paper is to identify whether there exist genes that are frequently under-detected in Visium compared to bulk RNA-seq, and the underlying potential mechanism of under-detection in Visium. We collected paired Visium and bulk RNA-seq data for 28 human samples and 19 mouse samples, which covered diverse tissue sources. We compared the two data types and observed that there indeed exists a collection of genes frequently under-detected in Visium compared to bulk RNA-seq. We performed a motif search to examine the last 350 bp of the frequently under-detected genes, and we observed that the poly (T) motif was significantly enriched in genes identified from both human and mouse data, which matches with our previous finding about frequently under-detected genes in scRNA-seq. We hypothesized that the poly (T) motif may be able to form a hairpin structure with the poly (A) tails of their mRNA transcripts, making it difficult for their mRNA transcripts to be captured during Visium library preparation.
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Perfilação da Expressão Gênica , Transcriptoma , Camundongos , Humanos , Animais , Perfilação da Expressão Gênica/métodos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de RNA/métodos , Análise de Sequência de RNA/estatística & dados numéricos , RNA-Seq/métodos , Biologia Computacional/métodos , Motivos de NucleotídeosRESUMO
The objective of this research was to examine the effectiveness of chitosan (CH)-gallic acid (GA) conjugate (CH-g-GA) as an edible coating in improving the physicochemical properties and oxidative stability of deep-fat fried pork meatballs. The meatballs were coated with either CH alone, a combination of CH and GA, or CH-g-GA before being fried at 180 °C for 5 min. The viscosity of the coating solutions influenced the amount of coating picked up by the meatballs, with higher viscosity coatings showing increased pickup. The application of chitosan-based coatings in deep-fried meatballs resulted in a decrease in moisture loss and oil uptake, as well as decreased b* values and hardness, while maintaining consistent cooking yield. Furthermore, compared to the control group, the chitosan-based coatings treatment significantly increased the ratio of immobilized water and decreased the ratio of free water (P < 0.05), as well as effectively inhibited lipid oxidation in deep-fried meatballs (P < 0.05). Among the different coatings tested, CH-g-GA coating exhibited the highest effectiveness. The research findings suggest that the CH-g-GA edible coating has significant potential in enhancing the overall quality of deep-fried meatballs.