Oleic acid is an endogenous ligand of TLX/NR2E1 that triggers hippocampal neurogenesis.

Neural stem cells, the source of newborn neurons in the adult hippocampus, are intimately involved in learning and memory, mood, and stress response. Despite considerable progress in understanding the biology of neural stem cells and neurogenesis, regulating the neural stem cell population precisely has remained elusive because we have lacked the specific targets to stimulate their proliferation and neurogenesis. The orphan nuclear receptor TLX/NR2E1 governs neural stem and progenitor cell self-renewal and proliferation, but the precise mechanism by which it accomplishes this is not well understood because its endogenous ligand is not known. Here, we identify oleic acid (18:1ω9 monounsaturated fatty acid) as such a ligand. We first show that oleic acid is critical for neural stem cell survival. Next, we demonstrate that it binds to TLX to convert it from a transcriptional repressor to a transcriptional activator of cell-cycle and neurogenesis genes, which in turn increases neural stem cell mitotic activity and drives hippocampal neurogenesis in mice. Interestingly, oleic acid-activated TLX strongly up-regulates cell cycle genes while only modestly up-regulating neurogenic genes. We propose a model in which sufficient quantities of this endogenous ligand must bind to TLX to trigger the switch to proliferation and drive the progeny toward neuronal lineage. Oleic acid thus serves as a metabolic regulator of TLX activity that can be used to selectively target neural stem cells, paving the way for future therapeutic manipulations to counteract pathogenic impairments of neurogenesis.

Functional and structural gradients reveal atypical hierarchical organization of Parkinson's disease.

Parkinson's disease (PD) patients exhibit deficits in primary sensorimotor and higher-order executive functions. The gradient reflects the functional spectrum in sensorimotor-associated areas of the brain. We aimed to determine whether the gradient is disrupted in PD patients and how this disruption is associated with treatment outcome. Seventy-six patients (mean age, 59.2 ± 12.4 years [standard deviation], 44 women) and 34 controls participants (mean age, 58.1 ± 10.0 years [standard deviation], 19 women) were evaluated. We explored functional and structural gradients in PD patients and control participants. Patients were followed during 2 weeks of multidisciplinary intensive rehabilitation therapy (MIRT). The Unified Parkinson's Disease Rating Scale Part III (UPDRS-III) was administered to patients before and after treatment. We investigated PD-related alterations in the principal functional and structural gradients. We further used a support vector machine (SVM) and correlation analysis to assess the classification ability and treatment outcomes related to PD gradient alterations, respectively. The gradients showed significant differences between patients and control participants, mainly in somatosensory and visual networks involved in primary function, and higher-level association networks (dorsal attentional network (DAN) and default mode network (DMN)) related to motor control and execution. On the basis of the combined functional and structural gradient features of these networks, the SVM achieved an accuracy of 91.2% in discriminating patients from control participants. Treatment reduced the gradient difference. The altered gradient exhibited a significant correlation with motor improvement and was mainly distributed across the visual network, DAN and DMN. This study revealed damage to gradients in the brain characterized by sensorimotor and executive control deficits in PD patients. The application of gradient features to neurological disorders could lead to the development of potential diagnostic and treatment markers for PD.

SPA-STOCSY: an automated tool for identifying annotated and non-annotated metabolites in high-throughput NMR spectra.

MOTIVATION: Nuclear magnetic resonance spectroscopy (NMR) is widely used to analyze metabolites in biological samples, but the analysis requires specific expertise, it is time-consuming, and can be inaccurate. Here, we present a powerful automate tool, SPatial clustering Algorithm-Statistical TOtal Correlation SpectroscopY (SPA-STOCSY), which overcomes challenges faced when analyzing NMR data and identifies metabolites in a sample with high accuracy. RESULTS: As a data-driven method, SPA-STOCSY estimates all parameters from the input dataset. It first investigates the covariance pattern among datapoints and then calculates the optimal threshold with which to cluster datapoints belonging to the same structural unit, i.e. the metabolite. Generated clusters are then automatically linked to a metabolite library to identify candidates. To assess SPA-STOCSY's efficiency and accuracy, we applied it to synthesized spectra and spectra acquired on Drosophila melanogaster tissue and human embryonic stem cells. In the synthesized spectra, SPA outperformed Statistical Recoupling of Variables (SRV), an existing method for clustering spectral peaks, by capturing a higher percentage of the signal regions and the close-to-zero noise regions. In the biological data, SPA-STOCSY performed comparably to the operator-based Chenomx analysis while avoiding operator bias, and it required <7 min of total computation time. Overall, SPA-STOCSY is a fast, accurate, and unbiased tool for untargeted analysis of metabolites in the NMR spectra. It may thus accelerate the use of NMR for scientific discoveries, medical diagnostics, and patient-specific decision making. AVAILABILITY AND IMPLEMENTATION: The codes of SPA-STOCSY are available at https://github.com/LiuzLab/SPA-STOCSY.

Relative importance between nitrification and denitrification to N2 O from a global perspective.

Nitrous oxide (N2 O) is a potent greenhouse gas, and its mitigation is a pressing task in the coming decade. However, it remains unclear which specific process between concurrent nitrification and denitrification dominates worldwide N2 O emission. We snagged an opportunity to ascertain whence the N2 O came and which were the controlling factors on the basis of 1315 soil N2 O observations from 74 peer-reviewed articles. The average N2 O emission derived from nitrification (N2 On ) was higher than that from denitrification (N2 Od ) worldwide. The ratios of nitrification-derived N2 O to denitrification-derived N2 O, hereof N2 On :N2 Od , exhibited large variations across terrestrial ecosystems. Although soil carbon and nitrogen content, pH, moisture, and clay content accounted for a part of the geographical variations in the N2 On :N2 Od ratio, ammonia-oxidizing microorganisms (AOM):denitrifier ratio was the pivotal driver for the N2 On :N2 Od ratios, since the AOM:denitrfier ratio accounted for 53.7% of geographical variations in N2 On :N2 Od ratios. Compared with natural ecosystems, soil pH exerted a more remarkable role to dictate the N2 On :N2 Od ratio in croplands. This study emphasizes the vital role of functional soil microorganisms in geographical variations of N2 On :N2 Od ratio and lays the foundation for the incorporation of soil AOM:denitrfier ratio into models to better predict N2 On :N2 Od ratio. Identifying soil N2 O derivation will provide a global potential benchmark for N2 O mitigation by manipulating the nitrification or denitrification.

The effect of polystyrene nanoplastics on arsenic-induced apoptosis in HepG2 cells.

Microplastics are detrimental to the environment. However, the combined effects of microplastics and arsenic (As) remain unclear. In this study, we investigated the combined effects of polystyrene (PS) microplastics and As on HepG2 cells. The results showed that PS microplastics 20, 50, 200, and 500 nm in size were taken up by HepG2 cells, causing a decrease in cellular mitochondrial membrane potential. The results of lactate dehydrogenase release and flow cytometry showed that PS microplastics, especially those of 50 nm, enhanced As-induced apoptosis. In addition, transcriptome analysis revealed that TP53, AKT1, CASP3, ACTB, BCL2L1, CASP8, XIAP, MCL1, NFKBIA, and CASP7 were the top 10 hub genes for PS that enhanced the role of As in HepG2 cell apoptosis. Our results suggest that nano-PS enhances As-induced apoptosis. Furthermore, this study is important for a better understanding of the role of microplastics in As-induced hepatotoxicity.

Leonuride protects diabetic nephropathy by activating SREBPs pathway.

Diabetic nephropathy (DN), a micro vascular complication of diabetes, is the main cause of end-stage renal disease, with a morbidity over 40% of diabetes. High glucose and lipid metabolism dysfunction are the leading cause of the development of DN. Previous study demonstrated that increased expression or activation of SREBPs in models of DN. Leonuride (LE), as an active constituent of Leonurus japonicus Houttuyn, has multiple biological activities, including antioxidant and anti-inflammatory effects. Previous studies showed that increasing the degradation of mature SREBPs is a robust way of lowering lipids and improve lipid metabolism dysfunction. However, effective regulation method of SREBPs degradation are still lacking. Herein, this study indicated that LE can effectively improve glucose and lipid metabolism disorders. In addition, the kidney function was also improved by inhibition of SREBPs activities in streptozocin (STZ)-induced type II diabetic mice. To our knowledge, this is the first time to describe the detailed mechanism of LE on the inhibition of precursor SREBPs, which would present a new direction for diabetic nephropathy treatment.

Metabolomics-based exploration the response mechanisms of Saussurea involucrata leaves under different levels of low temperature stress.

BACKGROUND: Saussurea involucrata (Sik.) is alpine plant that have developed special adaptive mechanisms to resist adverse environmental conditions such as low temperature chilling during long-term adaptation and evolution. Exploring the changes of its metabolites under different temperature stresses is helpful to gain insight into its cold stress tolerance. METHODS: Ultra-performance liquid chromatography and tandem mass spectrometry were used to analyze the metabolites in the leaves of Sik. under low different temperature stress conditions. RESULTS: A total of 753 metabolites were identified, and 360 different metabolites were identified according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) involved in the biosynthesis of secondary metabolites and amino acids and sugars. Sucrose and trehalose synthesis, glycolysis, tricarboxylic acid cycle, pentose phosphate pathway, glutamic acid-mediated proline biosynthesis, purine metabolism, amino acid metabolism, phenylpropane synthesis pathway metabolites all respond to low temperature stress. Under cold stress conditions, carbohydrates in Sik. leaves accumulate first than under freezing conditions, and the lower the temperature under freezing conditions, the less amino acids accumulate, while the phenolic substances increase. The expression of various substances in LPE and LPC increased more than 10-fold after low temperature stress compared with the control, but the content of LPE and LPC substances decreased after cold adaptation. In addition, purines and phenolics decreased and amino acids accumulated significantly under freezing conditions. CONCLUSION: The metabolic network of Sik. leaves under different low temperature stress conditions was proposed, which provided a reference for further exploration of the metabolic mechanism related to low temperature stress tolerance of Sik.

Anti-mesothelin CAR-T immunotherapy in patients with ovarian cancer.

Recently, chimeric antigen receptor T cell (CAR-T) therapy has received increasing attention as an adoptive cellular immunotherapy that targets tumors. However, numerous challenges remain for the effective use of CAR-T to treat solid tumors, including ovarian cancer, which is an aggressive and metastatic cancer with a poor therapeutic response. We screened for an effective anti-MSLN single-chain Fv antibody with comparable binding activity and non-off-target properties using human phage display library. A second-generation of anti-MSLN CAR was designed and generated. We demonstrated the efficacy of our anti-MSLN CAR-T cells for ovarian cancer treatment in an in vitro experiment to kill ovarian tumor cell lines. The anti-MSLN CAR-T cells impeded MSLN-positive tumor growth concomitant with a significant increase in cytokine levels compared with the control. Then, we demonstrated the efficacy of anti-MSLN CAR-T cells in an in vivo experiment against ovarian cancer cell-derived xenografts. Furthermore, we herein report three cases with ovarian cancer who were treated with autologous anti-MSLN CAR-T cells and evaluate the safety and effectiveness of adoptive cell therapy. In this investigator-initiated clinical trials, no patients experienced cytokine release syndrome or neurological symptoms over 2 grads. Disease stabilized in two patients, with progression-free survival times of 5.8 and 4.6 months. Transient CAR expression was detected in patient blood after infusion each time. The tumor partially subsided, and the patient's condition was relieved. In conclusion, this work proves the efficacy of the anti-MSLN CAR-T treatment strategy in ovarian cancer and provides preliminary data for the development of further clinical trials.

Global variations and controlling factors of anammox rates.

Soil anammox is an environmentally friendly way to eliminate reactive nitrogen (N) without generating nitrous oxide. Nevertheless, the current earth system models have not incorporated the anammox due to the lack of parameters in anammox rates on a global scale, limiting the accurate projection for N cycling. A global synthesis with 1212 observations from 89 peer-reviewed papers showed that the average anammox rate was 1.60 ± 0.17 nmol N g-1 h-1 in terrestrial ecosystems, with significant variations across different ecosystems. Wetlands exhibited the highest rate (2.17 ± 0.31 nmol N g-1 h-1 ), followed by croplands at 1.02 ± 0.09 nmol N g-1 h-1 . The lowest anammox rates were observed in forests and grasslands. The anammox rates were positively correlated with the mean annual temperature, mean annual precipitation, soil moisture, organic carbon (C), total N, as well as nitrite and ammonium concentrations, but negatively with the soil C:N ratio. Structural equation models revealed that the geographical variations in anammox rates were primarily influenced by the N contents (such as nitrite and ammonium) and abundance of anammox bacteria, which collectively accounted for 42% of the observed variance. Furthermore, the abundance of anammox bacteria was well simulated by the mean annual precipitation, soil moisture, and ammonium concentrations, and 51% variance of the anammox bacteria was accounted for. The key controlling factors for soil anammox rates differed from ecosystem type, for example, organic C, total N, and ammonium contents in croplands, versus soil C:N ratio and nitrite concentrations in wetlands. The controlling factors in soil anammox rate identified by this study are useful to construct an accurate anammox module for N cycling in earth system models.

IFI6 Downregulation Reverses Oxaliplatin Resistance of Colorectal Cancer Cells by Activating the ROS-Induced p38MAPK Signaling Pathway.

Oxaliplatin (OXA) is a usual chemotherapeutic agent applied in the colorectal cancer (CRC) clinical treatment. Interferon-alpha inducible protein 6 (IFI6) has been proved to promote proliferation and suppress apoptosis in several tumor cells, while the impacts of IFI6 on OXA resistance in CRC still need exploration. HCT116 and SW620 cells were used as the parental to obtain OXA-resistant cells. The influence of IFI6 on OXA sensitivity, cell proliferation and apoptosis were evaluated by overexpression or knockdown IFI6 in cells. In this work, we found that the level of IFI6 was significantly enhanced in HCT116/OXA and SW620/OXA cells as compared to the parental cells. Overexpression of IFI6 decreased the sensitivity of HCT116 and SW620 cells to OXA. However, knockdown of IFI6 enhanced the sensitivity of HCT116/OXA and SW620/OXA cells to OXA. And upregulated IFI6 promoted the proliferation and repressed apoptosis in HCT116 cells, while suppressed IFI6 markedly reduced proliferation and increased apoptosis in HCT116/OXA cells. Additionally, IFI6 suppressed the phosphorylation level of p38, and silenced IFI6 enhanced it. The addition of the p38 kinase inhibitor, SB203580, alleviated the decreased cell proliferation and increased apoptosis in HCT116/OXA cells. Suppressed IFI6 enhanced the reactive oxygen species (ROS) level in HCT116/OXA cells, and blockade of ROS with N-acetyl-L-cysteine (NAC) decreased the enhancement level of ROS and the phosphorylation level of the p38, which was induced by IFI6 down-regulation. We, therefore, implied that suppressed IFI6 reverses OXA-resistance of CRC cells via promoting the ROS-induced p38 mitogen-activated protein kinase (MAPK) signaling pathway.

Polystyrene nanoplastics promote the apoptosis in Caco-2 cells induced by okadaic acid more than microplastics.

Microplastics (MPs) are widespread in the environment and can be ingested through food, water, and air, posing a threat to human health. In addition, MPs can have a potential combined effect with other toxic compounds. Polystyrene (PS) has been shown to enhance the cytotoxicity of okadaic acid (OA). However, it remains unclear whether this enhancement effect is related to the size of PS particles. In this study, we investigated the mechanism of the combined effect of PS microplastics (PS-MPs) or PS nanoplastics (PS-NPs) and OA on Caco-2 cells. The results indicated that PS-NPs enhanced the cytotoxicity of OA and induced endoplasmic reticulum (ER) stress-mediated apoptosis in Caco-2 cells, compared to PS-MPs. Specifically, PS-NPs and OA cause more severe oxidative stress, lactate dehydrogenase (LDH) release, and mitochondrial membrane depolarization. Furthermore, it induced intracellular calcium overload through store-operated channels (SOCs) and activated the PERK/ATF-4/CHOP pathway to cause ER stress. ER stress promoted mitochondrial damage and finally activated the caspase family to induce apoptosis. This study provided an indirect basis for the assessment of the combined toxicity of MPs or NPs with OA.

Comparative Different Interventions to Improve Medication Adherence in Patients with Hypertension: A Network Meta-analysis.

BACKGROUND: Hypertension has become a major public problem. One of every 4 adults has hypertension. Medications are critical in controlling blood pressure, but patient medication adherence is low. Therefore, it is very crucial to promote medication adherence. However, the complexity and variety of interventions cause clinical decision-making difficulties for health managers and patients. OBJECTIVE: The aim of this study was to compare the effectiveness of different interventions to improve medication adherence in patients with hypertension. METHODS: We searched PubMed, Cochrane Library, Web of Science, EMBASE, Wan Fang, China National Knowledge Infrastructure, China Science and Technology Journal Database, and China Biology Medicine disc databases for eligible studies. Medication adherence rate and medication adherence difference were assessed as outcomes. Sensitivity analysis and inconsistency detection were performed to evaluate whether the exclusion of high-risk studies affected the validity. The risk of bias was assessed using the risk of bias table in Review Manager 5.4. The surface under the cumulative ranking curve was used to estimate the rankings among different interventions. RESULTS: Twenty-seven randomized controlled trials were included, and the interventions involved were categorized into 8 different categories. The network meta-analysis showed that the health intervention was the best to promote medication compliance in patients with hypertension. CONCLUSIONS: Health intervention is recommended to improve medication adherence in patients with hypertension. CLINICAL IMPLICATIONS: Health managers are recommended to provide health intervention to patients with hypertension to improve their medication adherence. This approach reduces morbidity, mortality, and healthcare costs for patients with cardiovascular disease.

Extracellular vesicles derived from Pinctada martensii mucus regulate skin inflammation via the NF-κB/NLRP3/MAPK pathway.

Extracellular vesicles (EVs) and their exosome subsets are vesicle-like nanoparticles (EVs) that are secreted by cells and contain various factors that treat various diseases. However, studies on extracting EVs from marine shellfish are still relatively lacking. In this study, EVs were isolated from Pinctada martensii mucus and the efficacy of EVs in modulating the inflammatory environment was demonstrated. A human skin inflammatory cell model was established to investigate the effect of Pinctada martensii mucus-derived EVs on inflammation. The results showed that EVs could restore the viability of inflammatory HaCaT cells and decrease the level of reactive oxygen species (ROS), as well as the mRNA expression of IL-6, IL-8 and TNF-α. The inflammation of HaCaT cells was treated by inhibiting the activation of the MAPK, NF-κB and NLRP3 inflammasome signaling pathways, which prevented the phosphorylation of related inflammatory proteins and the entry of P65 protein into the nucleus. This study provides novel EVs from marine shellfish-derived bioactive materials.

Protective effect of γ-glutamylcysteine against UVB radiation in NIH-3T3 cells.

BACKGROUND: Ultraviolet (UV) radiation-induced oxidative stress is the main cause of photodamage to the skin. Glutathione (GSH) serves important physiological functions, including scavenging oxygen-free radicals and maintaining intracellular redox balance. γ-glutamylcysteine (γ-GC), as an immediate precursor of GSH and harboring antioxidant and anti-inflammatory properties, represents an unexplored option for skin photodamage treatment. PURPOSE: The purpose of this study was to investigate whether γ-GC can reduce UVB-induced NIH-3T3 cell damage. METHODS: The experimental groups were as follows: control, UVB radiation, UVB radiation after pretreatment with γ-GC. Cell counting kit-8 (CCK-8) assays were used to measure cell proliferation, flow cytometry, and immunoblotting to detect the apoptosis rate and apoptosis-associated proteins. The levels of Reactive Oxygen Species (ROS), Superoxide Dismutase (SOD), and GSH/GSSG (oxidized GSH) were measured to assess oxidative stress. Immunoblotting and immunofluorescence were used to detect DNA damage. The members of the MAPK signaling pathways were detected by immunoblotting. RESULTS: UVB irradiation significantly reduced cell viability and destroyed the oxidative defense system. Pretreatment with γ-GC reduced UVB-induced cytotoxicity, restored the oxidation defense system, and inhibited activation of the MAPK pathway. It also reduced the apoptosis rate, downregulated the levels of cleaved caspase 3 and cleaved PARP. Furthermore, pretreatment with γ-GC reduced the accumulation of γH2AX after UVB radiation exposure, indicating that γ-GC could protect cells from DNA damage. CONCLUSION: γ-GC protected NIH-3T3 from damage caused by UVB irradiation. The photoprotective effect of γ-GC is mediated via strengthening the endogenous antioxidant defense system, which prevents DNA damage and inhibits the activation of the MAPK pathway.

Research on Improving Satellite Positioning Precision Based on Multi-Frequency Navigation Signals.

In satellite positioning systems, optimizing navigation satellite constellation and reducing the observation residuals are usually adopted to improve positioning precision and accuracy of the receiver. This paper presents a method to improve positioning precision by using multi-frequency navigation signals. The observation data of CAPS and GPS system are used to simulate the experiment. When the number of downlink frequencies is different, the root mean square of positioning error, improvement percentage, and standard deviation are calculated, respectively. When the number of descending frequencies is k, the root mean square of positioning error in three-dimensional space is 1/k of that in single frequency. The theoretical derivation and experiment show that the precision of satellite positioning can be effectively improved by using multi-frequency navigation signals. The research work can provide theoretical support and data reference for the future research of satellite positioning.

Concentration-dependent photoluminescence carbon dots for visual recognition and detection of three tetracyclines.

Concentration-dependent photoluminescence carbon dots (CDs) have been successfully synthesized through the one-step hydrothermal treatment of o-phthalic acid and ethylenediamine. The CDs possessed higher fluorescence quantum yield, up to 39.22%, exhibiting distinguished optical property, water solubility, and stability. The CDs that emit strong blue-green fluorescence can visually identify and determine tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC). TC quenched the fluorescence of CDs at 500 nm owing to the inner filter effect; OTC behaved similarly, but the emission wavelength of CDs was red-shifted to 515 nm. Inversely, once CTC was introduced to CDs solution, the fluorescence increased and the emission peak was blue-shifted to 450 nm. Bandgap transition and electrostatic interaction were proposed to be the mechanisms for the detection of OTC and CTC by CDs. Wide linear relationships were established for TC, OTC, and CTC with the limits of detection to be 50 nM, 36 nM, and 373 nM, respectively. Furthermore, the nanoscale probe constructed by this system has been applied to detect tetracyclines (TCs) in complex samples with satisfying recoveries (93.2-114%) and was designed as a portable test strip sensor for visually on-site TCs of honey sample screening. Accordingly, the preparation process of the nano fluorescent probe is simple and environmentally friendly, and the probe has a specific recognition ability for tetracyclines. The synthesized CDs in this work provide a new orientation for fast, effective, and visual real-time detection of tetracycline in actual samples.

Knowledge, attitude and practice of residents in the prevention and control of COVID-19: An online questionnaire survey.

AIMS: To explore the status quo and the influencing factors of residents' knowledge, attitude and practice (KAP) in the prevention and control of coronavirus disease 2019 (COVID-19), and the difficulties or challenges perceived by residents in their preventive practice. DESIGN: An online questionnaire survey. METHODS: The self-designed questionnaire was distributed among residents online in February 2020. Descriptive statistics, two independent samples t-tests, one-way analysis of variance, Pearson's correlation analysis, multivariate linear regression and content analysis were performed. RESULTS: A total of 919 valid questionnaires were collected. The scoring rates of residents' KAP were 85.2%, 92.9% and 84.4% respectively. Main factors influencing residents' knowledge included gender and occupation; while those influencing attitude were occupation, family economic level and knowledge; and those influencing practice included place of residence, occupation, with or without chronic disease, knowledge and attitude. Mass media was the primary approach for people to learn the knowledge and information of COVID-19. Difficulties or challenges faced were mainly lack of protective equipments, concerns about the risk of prevention and control, impact on daily life, work and study, lack of knowledge and consensus, psychological problems and information problems. CONCLUSION: The attitude of residents towards COVID-19 prevention and control is generally positive. The knowledge and practice have been popularized to a certain extent, but there are still deviations or deficiencies in residents' understanding of certain important knowledge and the adoption of relevant preventive measures. Evidence-based tailored public education initiatives are indicated. IMPACT: Findings of this study add important knowledge about residents' understanding, attitude, practice and the influencing factors on COVID-19 prevention and control, which serves as a scientific foundation for optimizing the pandemic public education and decision-making.

Colorimetric determination of acid phosphatase activity and inhibitor screening based on in situ polymerization of aniline catalyzed by gold nanoparticles.

A colorimetric assay for acid phosphatase (ACP) was constructed that is based on in situ polymerization of aniline catalyzed by gold nanoparticles (AuNPs). Aniline can be polymerized by ammonium persulfate (APS) in acidic condition and form gold-polyaniline core-shell nanoparticles (Au@PANI NPs) in the presence of AuNPs with the assistance of sodium dodecyl sulfate (SDS). AuNPs were also found to accelerate the polymerization process of aniline and thus shorten the reaction time. Upon the introduction of ascorbic acid (AA), the oxidant APS was consumed via the redox reaction. That led to the suppression of the formation of PANI. Consequently, ACP activity can be supervised on the basis of hydrolysis of 2-phospho-L-ascorbic acid trisodium salt (AAP) catalyzed by ACP to release AA. With the increase of ACP activity, the intensity ratio of the absorbance at λ705 nm (A705) and the absorbance at λ530 nm (A530) gradually decreased and the color gradually changed from dark-green to light-green to blue-gray to purple and eventually to pink. This method for ACP determination worked in the range 0.40 to 2.00 U·L-1. The detection limit is 0.043 U·L-1. The assay was applied to determine ACP in human serum. The recovery ranged from 81.0 to 104.6%. Relative standard deviation was less than 5%. This suits the request for biological sample analysis. Graphical abstract Schematic presentation of the colorimetric determination of acid phosphatase activity and inhibitor screening based on in situ polymerization of aniline catalyzed by gold nanoparticles. : acid phosphatase (ACP); : gold nanoparticles (AuNPs); : gold-polyaniline core-shell nanoparticles (Au@PANI NPs); ascorbic acid (AA); 2-phospho-L-ascorbic acid trisodium salt (AAP).

Clinical observation of macular choroidal thickness in primary chronic angle-closure glaucoma.

PURPOSE: To comparatively analyze differences in macular choroidal thickness and volume in primary chronic angle-closure glaucoma (PACG) eyes. METHODS: Thirty-one PACG patients were sequentially selected for this case-control study. Thirty-one eyes with PACG were included in group A, 31 fellow eyes were included in group B, and group C included 67 normal eyes. Enhanced-depth imaging optical coherence tomography (EDI-OCT) was used to measure choroidal thickness and volume. RESULTS: The choroidal thicknesses and volumes of the central subfield macula (CSM), nasal inner macula (NIM), temporal inner macula (TIM), inferior inner macula (IIM), temporal outer macula (TOM), inferior outer macula (IOM), and mean macula (MM) in group A were all higher than those in group C (P < 0.05). The choroidal thicknesses and volumes of the NIM, superior inner macula (SIM), IIM, nasal outer macula (NOM), and MM in group B were all higher than those in group C (P < 0.05). No statistically significant differences were found between groups A and B (P > 0.05). The choroidal thicknesses of different macular regions in group A were not correlated with the mean defect (MD). CONCLUSION: Increased macular choroidal thickness may be a common anatomical characteristic of PACD eyes. Macular choroidal thickness is not a good marker for assessing PACG severity.

Colorimetric determination of tyrosinase based on in situ silver metallization catalyzed by gold nanoparticles.

Gold nanoparticles (AuNPs) catalyze the mild reaction between the weak reducing agent kojic acid (KA) and silver ions (Ag+) to form Au@Ag bimetallic NPs by the combination of the intrinsic catalysis with plasmonic properties This is proposed as a novel optical assay to determine the tyrosinase (TYRase) concentration. The nanoparticles have been characterized by UV-vis spectroscopy, transmission electron microscope (TEM) images, and X-ray photoelectron spectroscopy (XPS). The sensing mechanism is based on the fact that KA binds to TYRase by chelating with dicopper active site of TYRase and the introduction of TYRase restrains the Au@Ag bimetallic NP formation by the precedent binding with KA. A clear color variation from yellow to pink and UV-vis spectral changes are observed at the optimal wavelength of 410 nm. The assay works in the range 0.13~0.73 U mL-1 with a detection limit (LOD) of 0.019 U mL-1. The impact from matrix interfering substances including glucose, uric acid, common oxidases, and amino acids is negligible. The applicability is demonstrated by quantitative determination of TYRase in human serum samples with 74 to 89% recovery and RSD less than 4.0%, which accords with the level for bio-sample analysis. Graphical abstract Schematic presentation of colorimetric assay for tyrosinase (TYRase) based on the inhibition effect on silver deposition onto catalytically active gold nanoparticles (AuNPs) and its application with a smartphone. Tyrosinase (TYRase); silver ions (Ag+); kojic acid (KA); gold nanoparticles (AuNPs); gold-silver core-shell nanoparticles (Au@Ag NPs).