Smart Programmable Scalable Dual-Mode Diagnostic Logic Nanoflare Strategy for Dual-Tumor Marker Detection.

Compared with the single-marker detection scheme, the detection of multiple targets in the complex cell and biological environment can obtain more reliable detection results. Herein, we detected miRNA-21 and APE1 in two modes, AND and OR, respectively, based on gold nanoflares and simple logic components. In both modes, DNAzyme and APE1 can get rich fluorescence recovery results by breaking the DNA strands from the gold nanorods (AuNRs) and unquenching under different conditions. In vivo and in vitro experiments suggest that both nanoflares exhibit excellent biocompatibility and make efficient and sensitive judgments on the two targets. This strategy emphasizes the reuse nature of enzymes, and a small amount of target can generate a large amount of fluorescent signal in the logic device, which greatly reduces the detection limit when monitoring low-abundance targets. Since the short-stranded DNA component of the detection device is simple in composition and easy to program its probe sequence, it can be expanded into a detection system for the detection of other sets of related markers, which increases its potential for clinical application.

CXXC finger protein 4 inhibits the CDK18-ERK1/2 axis to suppress the immune escape of gastric cancer cells with involvement of ELK1/MIR100HG pathway.

Gastric cancer, is the fourth most common tumour type yet, ranks second in terms of the prevalence of cancer-related deaths worldwide. CXXC finger protein 4 (CXXC4) has been considered as a novel cancer suppressive factor, including gastric cancer. This study attempted to investigate the possible function of CXXC4 in gastric cancer and the underlying mechanism. The binding of the ETS domain-containing protein-1 (ELK1) to the long non-coding RNA MIR100HG promoter region was identified. Then, their expression patterns in gastric cancer tissues and cells (SGC7901) were detected. A CCK-8 assay was used to detect SGC7901 cell proliferation. Subsequently, SGC7901 cells were co-cultured with CD3+ T cells, followed by measurement of CD3+ T cell proliferation, magnitude of IFN-γ+ T cell population and IFN-γ secretion. A nude mouse model was subsequently developed for in vivo validation of the in vitro results. Low CXXC4 expression was found in SGC7901 cells. Nuclear entry of ELK1 can be inhibited by suppression of the extent of ELK1 phosphorylation. Furthermore, ELK1 is able to bind the MIR100HG promoter. Overexpression of CXXC4 resulted in weakened binding of ELK1 to the MIR100HG promoter, leading to a reduced proliferative potential of SGC7901 cells, and an increase in IFN-γ secretion from CD3+ T cells. Moreover, in vivo experiments revealed that CXXC4 inhibited immune escape of gastric cancer cells through the ERK1/2 axis. Inhibition of the CXXC4/ELK1/MIR100HG pathway suppressed the immune escape of gastric cancer cells, highlighting a possible therapeutic target for the treatment of gastric cancer.

Deficiency of SCAMP5 leads to pediatric epilepsy and dysregulation of neurotransmitter release in the brain.

Secretory carrier membrane proteins (SCAMPs) play an important role in exocytosis in animals, but the precise function of SCAMPs in human disease is unknown. In this study, we identified a homozygous mutation, SCAMP5 R91W, in a Chinese consanguineous family with pediatric epilepsy and juvenile Parkinson's disease. Scamp5 R91W mutant knock-in mice showed typical early-onset epilepsy similar to that in humans. Single-neuron electrophysiological recordings showed that the R91W mutation significantly increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) at a resting state and also increased the amplitude of evoked EPSCs. The R91W mutation affected the interaction between SCAMP5 and synaptotagmin 1 and may affect the function of the SNARE complex, the machinery required for vesicular trafficking and neurotransmitter release. Our work shows that dysfunction of SCAMP5 shifted the excitation/inhibition balance of the neuronal network in the brain, and the deficiency of SCAMP5 leads to pediatric epilepsy.

IL-8 is involved in radiation therapy resistance of esophageal squamous cell carcinoma via regulation of PCNA.

Esophageal squamous cell carcinoma (ESCC) is one of the prevalent and deadly cancers worldwide, especially in Eastern Asia. Our present study revealed that the expression of IL-8 was increased in radiation therapy resistance of ESCC cells. Targeted inhibition of IL-8 by its neutralization antibody (anti-IL-8) can re-sensitize ESCC cells to radiation therapy and suppress the expression of proliferating cell nuclear antigen (PCNA). IL-8 can regulate the expression of PCNA via modulating its mRNA stability and promoter activity. Mechanistically, IL-8 can regulate the expression of miR-27b-5p, which can directly bind with 3'UTR of PCNA to decrease its mRNA stability. Further, anti-IL-8 can decrease the expression of transcription factor YY1, which can bind with the promoter of PCNA to increase its transcription. Taken together, our data revealed that IL8 can regulate the radiation resistance of ESCC cells and expression of PCNA. It suggested that targeted inhibition of IL-8 may improve the clinical treatment efficiency of radio therapy.

Functional recombinant human Legumain protein expression in Pichia pastoris to enable screening for Legumain small molecule inhibitors.

Legumain (LGMN) is a lysosomal protease that can specifically hydrolyze proteins after carboxyl-terminal asparagine residues. It has been reported that Legumain is highly expressed in many human tumors and promotes the migratory and invasive activity of cancer cells. Due to the limitation of an abundant and affordable source of endogenous active Legumain for further function studies, we produced the recombinant protein in Pichia pastoris. The pPICZα-LGMN expression plasmid was constructed and transformed into Pichia pastoris strain and positive recombinants were identified. Fermentation conditions were optimized and it was found that Legumain was most highly expressed under pH 6 culture conditions. In addition, the enzyme activity of the purified Legumain was tested using a fluorogenic substrate (Z-Ala-Ala-Asn-AMC) assay and the optimum pH for the autocatalytic activation of recombinant Legumain was very acidic at a pH value of 3. The recombinant protein was then used to screen a library of compounds and small molecule 1773 (Terramycin) was shown to effectively inhibit Legumain enzyme activity. These results indicate that the Pichia pastoris expression system can produce highly active recombinant Legumain protein allowing it to be used for High-throughput screening (HTS) applications.

Four new monacolin analogs from Monascus purpureus-fermented rice.

Four new monacolin analogs, monacolin T (1), monacolin U (2) 6a-O-methyl-4,6-dihydromonacolin L (3), and 6a-O-ethyl-4,6-dihydromonacolin L (4) were isolated from the ethanolic extract of Monascus purpureus-fermented rice. Their structures were determined by a combination of 1D, 2D NMR experiments (1H-1HCOSY, HSQC, HMBC, and ROESY), and mass spectrometry. In vitro cytotoxic assay, all compounds were inactive at the concentration of 10 µM.

Two New Anisic Acid Derivatives from Endophytic Fungus Rhizopycnis vagum Nitaf22 and Their Antibacterial Activity.

Rhizopycnis acids A (1) and B (2), two new anisic acid derivatives, were obtained from the ethyl acetate extract of the fermentation cultures of Rhizopycnis vagum, an endophytic fungus isolated from the healthy tissues of Nicotiana tabacum. The structures of the two compounds were determined through a series of 1D and 2D NMR and HRMS spectral analyses. Both compounds were the first anisic acid derivatives containing methylbutanoic/methylbutenoic acid group found in fungi. 1 and 2 displayed antibacterial activity against six tested bacteria with IC50 values in the range 16.1~81.3 µg/mL.

Monascustin, an Unusual γ-Lactam from Red Yeast Rice.

Monascustin (1), an unusual γ-lactam, was isolated from an ethanol extract of the Monascus purpureus fermented rice. Its structure including the absolute configuration was determined by spectroscopic data analysis and confirmed by X-ray crystallography. A plausible biosynthetic pathway is discussed on the basis of amino acid derivatization. Compound 1 showed inhibitory activity against histone deacetylase 1.

Bioactive Dibenzo-α-pyrone Derivatives from the Endophytic Fungus Rhizopycnis vagum Nitaf22.

Six new dibenzo-α-pyrones, rhizopycnolides A (1) and B (2) and rhizopycnins A-D (3-6), together with eight known congeners (7-14), were isolated from the endophytic fungus Rhizopycnis vagum Nitaf22 obtained from Nicotiana tabacum. The structures of the new compounds were unambiguously elucidated using NMR, HRESIMS, TDDFT ECD calculation, and X-ray crystallography data. Rhizopycnolides A (1) and B (2) feature an uncommon γ-butyrolactone-fused dibenzo-α-pyrone tetracyclic skeleton (6/6/6/5), while rhizopycnin B (4) was the first amino group containing dibenzo-α-pyrone. Rhizopycnolides A (1) and B (2) are proposed to be biosynthesized from polyketide and tricarboxylic acid cycle pathways. The isolated compounds were tested for their antibacterial, antifungal, and cytotoxic activities. Among them, rhizopycnolide A (1), rhizopycnins C (5) and D (6), TMC-264 (8), penicilliumolide D (11), and alternariol (12) were active against the tested pathogenic bacteria Agrobacterium tumefaciens, Bacillus subtilis, Pseudomonas lachrymans, Ralstonia solanacearum, Staphylococcus hemolyticus, and Xanthomonas vesicatoria with MIC values in the range 25-100 µg/mL. Rhizopycnin D (6) and TMC-264 (8) strongly inhibited the spore germination of Magnaporthe oryzae with IC50 values of 9.9 and 12.0 µg/mL, respectively. TMC-264 (8) showed potent cytotoxicity against five human cancer cell lines (HCT-116, HepG2, BGC-823, NCI-H1650, and A2780) with IC50 values of 3.2-7.8 µM.

Four new taraxastane-type triterpenoic acids from Cirsium setosum.

Four new taraxastane-type triterpenoids acids 3ß,22α-dihydroxy-20-taraxasten-30-oic acid (1), 3ß-hydroxy-22-oxo-20-taraxasten-30-oic acid (2), 3-oxo-22α-hydroxy-20- taraxasten-30-oic acid (3), and 3ß,19ß-dihydroxy-20-taraxasten-30-oic acid (4) were isolated and characterized from Cirsium setosum (Willd.) MB. Their structures were determined by the combination of 1D and 2D NMR experiments ((1)H-(1)HCOSY, HSQC, HMBC and ROESY) and mass spectrometry. Compound 2 exhibited potent selective cytotoxicity against human ovarian cancer cell line A2780 with an IC50 value of 3.9 µM.

Enhancement of Palmarumycin C12 and C13 Production by the Endophytic Fungus Berkleasmium sp. Dzf12 in an Aqueous-Organic Solvent System.

The endophytic fungus Berkleasmium sp. Dzf12, isolated from Dioscorea zingiberensis, was found to produce palmarumycins C12 and C13 which possess a great variety of biological activities. Seven biocompatible water-immiscible organic solvents including n-dodecane, n-hexadecane, 1-hexadecene, liquid paraffin, dibutyl phthalate, butyl oleate and oleic acid were evaluated to improve palmarumycins C12 and C13 production in suspension culture of Berkleasmium sp. Dzf12. Among the chosen solvents both butyl oleate and liquid paraffin were the most effective to improve palmarumycins C12 and C13 production. The addition of dibutyl phthalate, butyl oleate and oleic acid to the cultures of Berkleasmium sp. Dzf12 significantly enhanced palmarumycin C12 production by adsorbing palmarumycin C12 into the organic phase. When butyl oleate was fed at 5% (v/v) in medium at the beginning of fermentation (day 0), the highest palmarumycin C12 yield (191.6 mg/L) was achieved, about a 34.87-fold increase in comparison with the control (5.3 mg/L). n-Dodecane, 1-hexadecene and liquid paraffin had a great influence on the production of palmarumycin C13. When liquid paraffin was added at 10% (v/v) in medium on day 3 of fermentation, the palmarumycin C13 yield reached a maximum value (134.1 mg/L), which was 4.35-fold that of the control (30.8 mg/L). Application of the aqueous-organic solvent system should be a simple and efficient process strategy for enhancing palmarumycin C12 and C13 production in liquid cultures of the endophytic fungus Berkleasmium sp. Dzf12.

Bis-naphtho-γ-pyrones from fungi and their bioactivities.

Bis-naphtho-γ-pyrones are an important group of aromatic polyketides derived from fungi. They have a variety of biological activities including cytotoxic, antitumor, antimicrobial, tyrosine kinase and HIV-1 integrase inhibition properties, demonstrating their potential applications in medicine and agriculture. At least 59 bis-naphtho-γ-pyrones from fungi have been reported in the past few decades. This mini-review aims to briefly summarize their occurrence, biosynthesis, and structure, as well as their biological activities. Some considerations regarding to synthesis, production, and medicinal and agricultural applications of bis-naphtho-γ-pyrones are also discussed.

Cytotoxic monacolin analogs from Monascus purpureus-fermented rice.

Two new monacolin analogs, monacolins O (1) and P (2), along with three known analogs, have been isolated from the ethanolic extract of Monascus purpureus-fermented rice. Their structures and absolute configurations were elucidated by spectroscopic methods, especially 2D NMR and CD spectral analyses as well as chemical method. Both 1 and 2 were tested against five tumor cell lines, and compound 1 exhibited selective cytotoxic activity against A2780 and A549 cell lines, with IC50 values of 3.7 and 8.0 µM, respectively.

[GC-MS analysis of low polar components from Ainsliaea yunnanensis].

OBJECTIVE: To analyze the chemical constituents of low polar components from ethanol extract of Ainsliaea yunnanensis. METHODS: The air-dried stems and leaves of Ainsliaea yunnanensis were extracted with ethanol using ultrasonic extration. After removal of solvent under reduced pressure, the residue was suspended in H2O, and then partitioned sequentially with petroleum ether, EtOAc and n-BuOH, respectively. Then the petroleum ether fraction was chromatographed on normal phase silica gels eluting with a gradient increasing Me2 CO in petroleum ether. Then the components of low polarity were separated from the petroleum ether-Me2CO(50:1 - 20: 1) fraction and identified by GC-MS, and the relative contents of the components were determined with area percentage method. RESULTS: 50 constituents were identified from the low polar components of Ainsliaea yunnanensis. CONCLUSION: The research provides a theoretical basis for the study of chemical constituents and pharmaceutical activities of Ainsliaea yunnanensis.

[Triterpene compounds of Ainsliaea yunnanensis].

The compounds of Ainsliaea yunnanensis were isolated and purified by various kinds of column chromatography methods and their structures were determined by spectroscopic data analysis. Twelve compounds were obtained from the petroleum ether of ethanolic extract of A. yunnanensis and elucidated as bauerenyl acetate (1), bauerenol (2), alpha-amyrin (3), psi-taraxasterol (4), beta-amyrin (5), echinocystic acid (6), multiflorenol (7), 3beta-hydroxy-olean-18-ene germanicol (8), 3beta-hexadecanoyl-12-oleanen-11-one (9), fernenol (10), fern-7-en-3beta-ol (11), and lupeol (12). All compounds were isolated from this genus for the first time except compound 1, 3, 5 and 10, and they were all isolated from this plant for the first time.

4,5-Dihydro-1,2,4-oxadiazole as a Single Nitrogen Transfer Reagent: Synthesis of Functionalized Isoxazoles Assisted by Sc(OTf)3 or Au(I)/Sc(OTf)3 Synergistic Catalysis.

A five-membered N-O heterocycle, 4,5-dihydro-1,2,4-oxadiazole, was found to act as a single nitrogen atom transfer reagent via elimination of a ketone/aldehyde and a nitrile. This reagent was successfully applied for the synthesis of isoxazoles from ynones promoted by Sc(OTf)3 or through Au(I)/Sc(OTf)3 synergistic catalysis. The efficiency of this protocol was also demonstrated by its application in modifications of structurally complex natural products and pharmaceuticals.

Photoredox/Nickel Dual-Catalyzed Regioselective Allylic Arylations of Allyl Trifluoroborates with Aryl Halides.

An efficient photoredox/nickel dual-catalyzed coupling of allyl trifluoroborates with aryl halides has been developed, which provides an attractive route to diverse-substituted allylic benzenes. The method offers several advantages, such as high efficiency and regioselectivity, mild reaction conditions, wide substrate scope, and functional group compatibility. Mechanistic studies suggest that a π-allyl nickel(III) intermediate generated via the addition of an allyl radical to nickel species is possibly formed as a key reaction intermediate.

An NIR-Driven Upconversion/C3N4/CoP Photocatalyst for Efficient Hydrogen Production by Inhibiting Electron-Hole Pair Recombination for Alzheimer's Disease Therapy.

Redox imbalance and abnormal amyloid protein (Aß) buildup are key factors in the etiology of Alzheimer's disease (AD). As an antioxidant, the hydrogen molecule (H2) has the potential to cure AD by specifically scavenging highly harmful reactive oxygen species (ROS) such as •OH. However, due to the low solubility of H2 (1.6 ppm), the traditional H2 administration pathway cannot easily achieve long-term and effective accumulation of H2 in the foci. Therefore, how to achieve the continuous release of H2 in situ is the key to improve the therapeutic effect on AD. As a corollary, we designed a rare earth ion doped g-C3N4 upconversion photocatalyst, which can respond to NIR and realize the continuous production of H2 by photocatalytic decomposition of H2O in biological tissue, which avoids the problem of the poor penetration of visible light. The introduction of CoP cocatalyst accelerates the separation and transfer of photogenerated electrons in g-C3N4, thus improving the photocatalytic activity of hydrogen evolution reaction. The morphology of the composite photocatalyst was shown by transmission electron microscopy, and the crystal structure was studied by X-ray diffractometry and Raman analysis. In addition, the ability of g-C3N4 to chelate metal ions and the photothermal properties of CoP can inhibit Aß and reduce the deposition of Aß in the brain. Efficient in situ hydrogen production therapy combined with multitarget synergism solves the problem of a poor therapeutic effect of a single target. In vivo studies have shown that UCNP@CoP@g-C3N4 can reduce Aß deposition, improve memory impairment, and reduce neuroinflammation in AD mice.

Trimer structures formed by target-triggered AuNPs self-assembly inducing electromagnetic hot spots for SERS-fluorescence dual-signal detection of intracellular miRNAs.

Accurate quantitative, in situ and temporal tracking imaging of tumor-associated miRNAs in living cells could provide a basis for cancer diagnosis and prognosis. In this strategy, a surface-enhanced Raman scattering (SERS)-fluorescence (FL) dual-spectral sensor (DSS) was constructed based on the nanoscale photophysical properties of AuNPs, mediated by functionalized DNA, to achieve rapid imaging of FL and accurate SERS quantification of intracellular miRNAs. The dual-spectrum sensor in the strategy is highly sensitive, specific and reproducibly stable. The LOD values of the dual spectra were 3.58 pM (SERS) as well as 11.8 pM (FL) with RSD values less than 2.69%. The bispectral sensor self-assembled into a trimer by the lapidation of Y-type DNA under the excitation of the target, generating a stable enhanced electric field coupling; and selected adenine located in the enhanced electric field as the reporter molecule, simplifying the labeling process and variables of the Raman reporter molecule, distinguishing it from other traditional methods. This strategy successfully achieved accurate tracking and quantification of miR-21 in cancer cells and showed good stability in the cells. The reported probes are potential tools for reliable monitoring of biomolecular dynamics in living cells.

Structure elucidation and NMR assignments of an unusual aromatic monacolin analog from Monascus purpureus-fermented rice.

One unusual aromatic monacolin analog, aromonacolin A (1), was isolated from the ethanolic extract of Monascus purpureus-fermented rice. Its structure was elucidated by extensive spectroscopic (HRESIMS, (1)H NMR, (13)C NMR, HSQC, HMBC, and NOESY) and chemical methods. The absolute configuration of the C-6 secondary alcohol was deduced via the circular dichroism data of the in situ formed [Rh(2)(OCOCF(3))(4)] complex.