Shape Control of Carbon Nanoparticles via a Simple Anion-Directed Strategy for Precise Endoplasmic Reticulum-Targeted Imaging.

Herein, small-sized fluorescent carbon nanoparticles (CNs) with tunable shapes ranging from spheres to various rods with aspect ratios (ARs) of 1.00, 1.51, 1.89, and 2.85 are prepared using a simple anion-directed strategy for the first time. Based on comprehensive morphological and structural characteristics of CNs, along with theoretical calculations of density functional theory and molecular dynamics simulations, their shape-control mechanism is attributed to interionic interactions-induced self-assembly, followed by carbonization. The endoplasmic reticulum-targeting accuracy of CNs is gradually enhanced as their shape changes from spherical to higher-AR rods, accompanied by a Pearson's correlation coefficient up to 0.90. This work presents a facile approach to control the shape of CNs and reveals the relationship between the shape and organelle-targeting abilities of CNs, thereby providing a novel idea to synthesize CNs that serve as precise organelle-targeted fluorescent probes.

Carbohydrate-restricted diet promotes skin senescence in senescence-accelerated prone mice.

This study used senescence-accelerated prone mice (SAMP8) to examine the effects of a carbohydrate-restricted diet on aging and skin senescence, to determine how long-term carbohydrate restriction affects the aging process. Three-week-old male SAMP8 mice were divided into three groups after 1 week of preliminary feeding: one was given a controlled diet, the other was given a high-fat diet, and the third was given a carbohydrate-restricted diet. Ad libitum feeding was administered until the mice reached 50 weeks of age. Before the end of the test period, a grading test was used to evaluate visible aging in the mice. After the test period, serum and skin samples in mice were obtained and submitted for analysis. As a result, the grading test demonstrated that there was significant progression of visible aging in the carbohydrate-restricted group, as well as a decreased survival rate. Histological examination of the skin revealed that the epidermis and dermis in the carbohydrate-restricted group had become thinner. Analysis of the mechanisms involved demonstrated an increase in serum interleukin-6, aggravated skin senescence, inhibition of skin autophagy and activation of skin mTOR. Therefore, this study proved that a carbohydrate-restricted diet promoted skin senescence in senescence-accelerated mice.

Facile synthesis of metal-organic framework-derived SiW12@Co3O4 and its peroxidase-like activity in colorimetric assay.

Over the past few years, artificial enzymes have attracted enormous attention due to their high stabilities and cost-effective productions. In this work, metal-organic framework-derived SiW12@Co3O4 was synthesized in large quantities by stirring the mixture at ambient temperature and calcination. The obtained SiW12@Co3O4 exhibited a highly inherent peroxidase-like activity and excellent stability. Kinetic studies demonstrated that the synthesized SiW12@Co3O4 had a strong binding affinity to 3,3',5,5'-tetramethylbenzidine (TMB), stronger than HRP had. Specifically, the peroxidase-like activity of SiW12@Co3O4 in an aqueous solution was well maintained after incubation at an elevated temperature, at an extreme pH and for a long time. A SiW12@Co3O4-based method was further developed for H2O2 and one-pot glucose detection with good sensitivity and reliability. The facile synthesis approach is expected to facilitate the practical use of metal-organic frameworks and their derivatives as enzyme mimics in the future.

The 1975 Japanese diet has a stress reduction effect in mice: search for physiological effects using metabolome analysis.

We aimed to find new physiological effects of the Japanese diet. First, to determine the key components in serum from mice fed the 1975 diet, serum from mice fed the 1960, 1975, 1990 or 2005 Japanese diet was analyzed using CE-TOFMS and LC-TOFMS. Based on these results, the key components were determined by principal component analysis. Among the identified compounds, GABA was included. Therefore, a stress reduction effect was inferred as a novel physiological effect of this diet. Next, we tested whether the 1975 diet had an actual stress reduction effect in mice. Mice were given the 1975 diet or a control diet for 4 weeks, after which they were divided into restraint stress and non-stress groups. Mice fed the 1975 diet had significantly decreased stress parameters compared with those fed the control diet. These results provide the first evidence that the 1975 Japanese diet has a stress reduction effect.

Intake of mulberry 1-deoxynojirimycin prevents colorectal cancer in mice.

The effect of 1-deoxynojirimycin, a caloric restriction mimetic, was examined in ICR mice with azoxymethane dextran sodium sulfate-induced colorectal cancer. Azoxymethane is a carcinogen (10 mg/kg body weight), and 2% dextran sodium sulfate (w/v) used as a colitis-inducing agent. Mice were separated into 5 groups: a group without colorectal cancer fed a normal diet (CO- group), and groups with colorectal cancer fed a normal diet (CO+ group), a calorie-restricted diet (caloric restriction group), and diets including 0.02% and 0.1% 1-deoxynojirimycin (l-1-deoxynojirimycin and H-1-deoxynojirimycin groups). The tumor incidence and number were reduced significantly in the caloric restriction group compared to the CO+ group, and were also suppressed in a dose-dependent manner by 1-deoxynojirimycin. mRNA for anti-apoptotic Bcl-2 was decreased and that for pro-apoptotic Bax was increased in the carcinoma tissue of CR, l-1-deoxynojirimycin and H-1-deoxynojirimycin groups. These results suggest that caloric restriction and 1-deoxynojirimycin inhibit growth of colorectal cancer by inducing apoptosis in an induced cancer model in mice.

Hydrophobic Carbon Nanodots with Rapid Cell Penetrability and Tunable Photoluminescence Behavior for in Vitro and in Vivo Imaging.

Tunable fluorescent emission and applications in both in vitro and in vivo imaging of hydrophobic carbon nanodots (CNDs) with rapid penetration capability are reported. The hydrophobic CNDs are prepared via hydrothermal treatment of ionic liquid 1-ethyl-3-methylimidazolium bromide and exhibit excitation-dependent photoluminescence behavior along with a red-shift in the excitation/emission maxima with concentration. The quantum yields of the as-prepared CNDs are in the range of 2.5-4.8% at an excitation wavelength of 300-600 nm. The rapid penetration behavior (within 1 min) of CNDs into the cell membrane significantly reduces the sample treatment time and avoids potential fluorescence quenching induced by the interaction between CNDs and samples. A co-location study reveals that the hydrophobic CNDs are distributed mainly in the lysosome. The potentials of the hydrophobic CNDs as fluorescent probe in in vitro and in vivo imaging are well demonstrated by the labeling of HeLa cells, MCF-7 cells, A549 cells, and Kunming mice.

High-fat diet intake from senescence inhibits the attenuation of cell functions and the degeneration of villi with aging in the small intestine, and inhibits the attenuation of lipid absorption ability in SAMP8 mice.

We examined the effect of a high-fat diet from senescence as a means of preventing malnutrition among the elderly. The senescence-accelerated mouse P8 was used and divided into three groups. The 6C group was given a normal diet until 6 months old. The 12N group was given a normal diet until 12 months old. The 12F group was given a normal diet until 6 months old and then a high-fat diet until 12 months old. In the oral fat tolerance test, there was a decrease in area under the curve for serum triacylglycerol level in the 12N group and a significant increase in the 12F group, suggesting that the attenuation of lipid absorption ability with aging was delayed by a high-fat diet from senescence. To examine this mechanism, histological analysis in the small intestine was performed. As a result, the degeneration of villi with aging was inhibited by the high-fat diet. There was also a significant decrease in length of villus in the small intestine in the 12N group and a significant increase in the 12F group. The high-fat diet from senescence inhibited the degeneration of villi with aging in the small intestine, and inhibited the attenuation of lipid absorption ability.

Synthesis and characterization of TiO2/hydrochar matrix composites for enhanced ammonia degradation.

This study explores the limitations of TiO2 as a photocatalyst, focusing on its narrow bandwidth and high electron-hole complexation probabilities that restrict its applications. A novel one-pot synthesis method for TiO2/hydrochar matrix composites is presented, with variations achieved through control of hydrothermal temperature, time, and loading concentration. The efficacy of these composites in ammonia removal is investigated, revealing optimal performance for the composite denoted as 3Ti-160-7, synthesized with a titanium salt concentration of 0.3 mol L-1, a hydrothermal temperature of 160 °C, and a hydrothermal time of 7 hours. Comparative analyses with commercial TiO2 (P25) and hydrochar demonstrate superior performance of 3Ti-160-7, exhibiting significantly lower ammonia concentration and reduced NO and NO2 concentrations. This research underscores the cost-effectiveness and application potential of TiO2/hydrochar matrix composites, offering valuable insights for the enhancement of photocatalytic activity and broader applicability in addressing TiO2-related challenges.

Tunable Organelle Imaging by Rational Design of Carbon Dots and Utilization of Uptake Pathways.

Employing one-step hydrothermal treatment of o-phenylenediamine and lysine to exploit their self- and copolymerization, four kinds of CDs (ECDs, NCDs, GCDs, and LCDs) are synthesized, possessing different surface groups (CH3, C-O-C, NH2, and COOH) and lipophilicity which endow them with various uptake pathways to achieve tunable organelle imaging. Specifically, highly lipophilic ECDs with CH3 group and NCDs with C-O-C group select passive manner to target to endoplasmic reticulum and nucleus, respectively. Amphiphilic GCDs with CH3, C-O-C and NH2 groups prefer caveolin-mediated endocytosis to locate at Golgi apparatus. Highly hydrophilic LCDs with CH3, NH2 and COOH groups are involved in clathrin-mediated endocytosis to localize in lysosomes. Besides, imaging results of cell division, three-dimensional reconstruction and living zebrafish demonstrate that the obtained CDs are promising potential candidates for specific organelle-targeting imaging.

Correction: Carbon dots with tunable dual emissions: from the mechanism to the specific imaging of endoplasmic reticulum polarity.

Correction for 'Carbon dots with tunable dual emissions: from the mechanism to the specific imaging of endoplasmic reticulum polarity' by Shuang E et al., Nanoscale, 2020, 12, 6852-6860, DOI: .

ß-Naphthothiazolium-based ratiometric fluorescent probe with ideal pKa for pH imaging in mitochondria of living cells.

The weakly alkaline microenvironment (pH ~8.0) in mitochondria plays a vital role in maintaining its morphology and function. Thus monitoring mitochondrial pH (pHmito) is of great significance. Herein, a ratiometric fluorescent probe (ENBT) for pHmito imaging in mitochondria of living cells is reported. pH variation closely correlates to intramolecular charge transfer (ICT) from naphthol to ß-naphthothiazolium. ENBT exhibits a remarkable decrease on ratiometric fluorescence at λem1/λem2 = F595/F700 in response to pH variation within 6.30-9.29. In addition, ENBT has an ideal pKa value of 7.94 ± 0.08, which is advantageous in accurate sensing of pHmito. Moreover, ENBT has a Stokes shift of >150 nm, which effectively eliminates the potential interference from the excitation irradiation. ENBT shows excellent capability for specific staining of mitochondria with low cytotoxicity, which is most suitable for pHmito imaging in live cells. The probe was applied for monitoring pHmito variation in mitochondria of live cells caused by H2O2, NAC (N-Acetyl-l-cysteine), NH4Cl, carbonyl cyanide m-chlorophenyl hydrazone (CCCP) and lactate/pyruvate. The morphological alterations of mitochondria in living cells after treatment by CCCP were further evaluated.

Green synthesis of aluminum-hydrochar for the selective isomerization of glucose to fructose.

Hydrochar microspheres supported Al catalysts with hierarchically porous structure (Al/HPHMs) for glucose to fructose isomerization were fabricated. Superior catalytic selectivity (93.3%) and fructose yield (32.6%) were achieved in aqueous under 160 °C for 20 min. Hierarchically porous structure was formed after KHCO3 and K2CO3 activation and the roles of KHCO3 and K2CO3 in controlling the Al phase and tailoring morphology of hydrochar supported Al were evaluated. The major active sites were characterized as Al hydroxides including ß-Al(OH)3, γ-Al(OH)3, γ-AlO(OH), Al-C-O linkages. Active sites by KHCO3 activation with high contents of Al-C-O and Al(OH)3 have better selectivity. Oxygen-containing functional groups including aluminum­oxygen groups on the hydrochar microspheres have contributed to the formation of hydrogen bond and π-π interactions between glucose and Al species. Green process synthesized aluminum-hydrochars have potential for their application as a variety of stable, recyclable, and efficient catalysts for lignocellulosic biorefining.

Corn stover valorization by one-step formic acid fractionation and formylation for 5-hydroxymethylfurfural and high guaiacyl lignin production.

One-step fractionation with concentrated formic acid at elevated temperatures with short retention time was investigated for corn stover valorization. Crude pulp (CP) with high purity of cellulose and FA-lignin (FAL) with high guaiacyl content were fractionated through one-step mild pretreatment. Formylation reaction on both CP and FAL fractions occurred during the pretreatment and improved the hydrophobicity and thermal stability of CPs and FALs. The presence of formyl group on CPs significantly inhibited the enzymatic hydrolysis efficiency for sugar production, however, the formylated cellulose showed super high reactivity and selectivity for HMF production through catalysis by maleic acid and aluminum chloride in acetonitrile-water co-solvent system. In addition, the fractionated FAL fraction exhibited a loose structure which is prominent for its further catalytic conversion into chemicals and energy.

[Genetic characteristics of HIV-1 primary drug resistance-associated mutations in treatment-naive individuals in Liaoning province, 2004-2008].

OBJECTIVE: To investigate the HIV-1 drug resistance associated mutations and examine the susceptibility of HIV-1 with these mutations to antiretroviral in treatment-naive individuals in Liaoning province from 2004 to 2008. METHODS: RNA was extracted from 20 plasma samples of diagnosed untreated HIV-1-infected treatment-naive patients by drawing method. After the viral loading (VL) test, the protease and nucleoside reverse transcriptase coding regions were amplified by RT-PCR, nested PCR and sequence analysis directly. Levels of resistance and prevalence were evaluated according to the Stanford University HIV Drug Resistance Database's algorithm (http://hivdb.stanford.edu). RESULTS: Among the 20 plasma samples, 13 got PCR products because of their VL values higher than 1000 copies/ml.Meanwhile, the 13 samples got 65 sequences by using 5 primers each. Polymorphisms in subtype H and circulating recombinant forms (CRFs) CRF10_CD sequences were identified. An overall prevalence of 30.8% (4/13) resistance to NNRTIs, 7.7% (1/13) to PI and no NRTIs mutations were found. The most frequent substitutions (4/13) in the RT region at positions P225H, K238S, V179D, K238T and a major position I54S in PR implied to a multiple drug-resistance. A71V or L10V only, respectively, substitution in PR was found in 3 samples, but no any worse with drug sensitivity. CONCLUSION: HIV-1 polymorphisms in subtype H and CRFs CRF10_CD sequences were identified circulating in Liaoning. A major mutation position I54S in PR implied that it would be the time to commence a higher level drug regimen.

Confinement of AuAg NCs in a Pomegranate-Type Silica Architecture for Improved Copper Ion Sensing and Imaging.

Metal nanoclusters (NCs) have been in focus received attention due to their superior optical properties, whereas their biomedical applications are limited by the relatively low quantum yield and poor cellular uptaking behaviors. In the present study, a pomegranate-type architecture with densely packed AuAg NCs is constructed, where the aminoterminated dendritic silica spheres (dNSiO2) with ultralarge central-radial pore channels act as an efficient absorbent host for self-assembling of AuAg NCs. The spatial confinement of AuAg NCs within the pomegranate-type silica architecture not only avoids the time-tedious purification procedure in metal NCs fabrication but also offer significant improvement of the photoluminescence performance of AuAg NCs, i.e., the quantum yield (17.0%) is nearly doubled when compared to that of free AuAg NCs. The presence of Cu2+ induces efficient quenching of the photoluminescence of obtained dNSiO2-AuAg NCs, achieving the sensitive detection of Cu2+ with a detection limit of 0.060 µM. Moreover, the pomegranate-type silica architecture serves itself as an excellent nanocarrier to deliver AuAg NCs into living cells, making dNSiO2-AuAg NCs an efficient probe for intracellular Cu2+ sensing and imaging.

Regulating the properties of carbon dots via a solvent-involved molecule fusion strategy for improved sensing selectivity.

Carbon dots (CDs) were prepared by a solvent-involved molecular fusion strategy using o-phenylenediamine (OPD) as the carbon source and formamide as the reaction solvent. The CDs possessed not only the functional groups inherited from the carbon source and the reaction solvent, but also numerous C=N groups in the structure, resulting from the Schiff base reaction between -NH2 of OPD and C=O of formamide. These functional groups endowed the final CDs with a favorable soft-base property, leading to the high tolerance level toward hard-acid type metal ions and prominent detection selectivity toward Ag+. Moreover, the obtained CDs displayed outstanding biocompatibility and low cytotoxicity, and demonstrated potential as an effective photoluminescence probe for intercellular Ag+ and Cys imaging, preventing the interference of autofluorescence from living tissues. This study focused on the solvent-involved molecular fusion strategy could provide new insights into the design of novel carbon-based nanostructures and optimization of the structure-property relationship of CDs.

Simultaneous Intake of Euglena gracilis and Vegetables Exerts Synergistic Anti-Obesity and Anti-Inflammatory Effects by Modulating the Gut Microbiota in Diet-Induced Obese Mice.

We determined whether the anti-obesity effect provided by the consumption of Euglena gracilis (Euglena), which is rich in insoluble dietary fiber, could be enhanced by the co-consumption of vegetables with an abundance of soluble dietary fiber. Nine-week-old male C57BL/6J mice were divided into five groups as follows: group 1 received a normal diet, group 2 received a high-fat diet, and groups 3, 4, and 5 received high fat diets containing 0.3% paramylon, 1.0% Euglena, or 1.0% Euglena plus 0.3% vegetables (barley leaf, kale, and ashitaba), respectively. Mice were fed ad libitum until 18 weeks of age. Euglena intake significantly reduced visceral fat accumulation in obese mice, and co-consumption of vegetables enhanced this effect. Consumption of Euglena with vegetables reduced adipocyte area, suppressed the expression of genes related to fatty acid synthesis, upregulated genes related to adipocyte lipolysis, and suppressed serum markers of inflammation. Notably, we also observed an increase in the fraction of short-chain fatty acid-producing beneficial bacteria, a reduction in harmful bacteria that cause inflammation, and an increase in short-chain fatty acid production. Therefore, the co-consumption of vegetables enhanced the anti-obesity and anti-inflammatory effects of Euglena, likely by modulating the gut microbiota composition.

Boronic acid functionalized g-C3N4 nanosheets for ultrasensitive and selective sensing of glycoprotein in the physiological environment.

As important biomarkers, glycoprotein sensing is frequently facilitated by boronic acid binding with its cis-diols. However, boronic acid based sensors suffer from drawbacks of alkali restriction and/or sensitivity limitation. Herein, we report boronic acid decorated g-C3N4 nanosheets (B-g-CN) with a Wulff-type boronic acid feature, which selectively bind glycoprotein under physiological conditions. Meanwhile, the binding causes significant enhancement of the B-g-CN nanosheet fluorescence, providing the basis for glycoprotein sensing. With IgG as a model, a detection limit (LOD) of 2.2 nM (3σ/s, n = 11) was obtained within a linear range of 6.7-67 nM. The LOD was further improved to 52 pM subject to enrichment of the nanosheets, which well enables IgG assay in human urine samples. Moreover, it was successful in imaging endogenous and exogenous glycoproteins in living cells.

Targeted imaging of the lysosome and endoplasmic reticulum and their pH monitoring with surface regulated carbon dots.

Organelles play crucial roles in cellular activities and the functions of organelles are related greatly to the pH values, therefore, the bio-imaging of targeted organelles and their related pH sensing is of great importance in biological assays. Herein we report the fluorescence imaging of specific organelles, i.e., lysosomes and endoplasmic reticulum, and their pH sensing with surface regulated carbon dots (CDs). Carbon dots functionalized with amine groups (ACDs) are first prepared by hydrothermal treatment of citric acid and urea, and then laurylamine functionalized CDs (LCDs) are obtained via the conjugation of laurylamine with ACDs. The as-prepared ACDs and LCDs provide clear and bright imaging results for the lysosome and endoplasmic reticulum, respectively. The subcellular targeting features of the two CDs are attributed to their surface chemistries and cellular uptake pathways. Moreover, both the CDs are pH responsive within a certain pH range, i.e., 4.0-5.4 for ACDs and 6.2-7.2 for LCDs. The ACDs and LCDs are thus successfully applied to visualize the pH fluctuations of the lysosome and endoplasmic reticulum in MCF-7 cells.