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A 2D-2D titanium dioxide nanosheet-reduced graphene oxide (TNS-rGO) composite with better electronic conductivity and hydrophilicity was prepared by the hydrothermal method. The as-obtained TNS-rGO composite was further functionalized with 3-aminopropyltriethoxysilane (APTES) to provide a large amount of –NH2 groups on the surface for anchoring ultrafine PdAg alloy nanoparticles with an average particle size of 1.69 nm by a facile wet reduction approach. Benefiting from the combined effects of well-dispersed PdAg alloy nanoparticles, facilitated electron transfer from TNS-rGO to Pd, and increased electron density of active sites, the Pd8Ag1/NH2-TNS-rGO catalyst exhibited excellent activity towards dehydrogenation of formic acid without adding any additives at 298 K, corresponding to an initial turn over frequency as high as 1090 h−1, which is much higher than that of most other state-of-the-art catalysts.

We report the synthesis of a novel type of carbon-based nanostructure, which is composed of a string of carbon nanopearl chains (CNPCs) with a connection structure of carbon nanofibers using a chem...

RNA interference (RNAi) was used to investigate the role of epididymal vascular endothelial growth factor (VEGF) gene expression on sperm hyaluronidase (HYD) in a rat model of arsenic poisoning and to identify a new gene therapy target for male infertility caused by arsenic poisoning. The Rat model of chronic arsenic poisoning was established. And we found that positive expression of VEGF and VEGF receptor 2 (VEGFR2) was observed by Immunohistochemical staining in the epididymal tissues of arsenic-exposed rats. Subsequently, VEGF-shRNA-1, VEGF-shRNA-2 and VEGF shRNA-3 expression vectors containing epididymal VEGF-shRNA lentivirus were constructed and injected into the bilateral epididymis of each group of rats (Control group, NC-shRNA negative infection group, VEGF-shRNA-1 group, VEGF-shRNA-2 group, VEGF-shRNA-3 group) (n = 10 per group). Compared with the negative infection group and the normal control group, the expression of VEGF and VEGFR2 mRNA and protein levels were significantly decreased following epididymal infection. In addition, the HYD activity was all significantly lower than that in the normal control group and the negative infection group. Taken together, epididymal VEGF gene silencing may inhibit the activity of sperm HYD through downregulating VEGFR2., Graphical abstract

The development of active and stable catalyst is of significance for hydrogen generation from formic acid. Herein, a novel palladium catalyst with ultrafine metallic nanoparticles anchored on NH2-functionalized reduced graphene oxide (NH2-rGO) was synthesized by a facile wet chemical reduction process using sodium borohydride as the reducing agent. The TEM and XPS characterization results confirmed the successful functionalization of rGO with 3-aminopropyltriethoxysilane (APTES), which plays a very important role in evenly dispersing ultrafine Pd nanoparticles with a small average size of about 2.3 nm. As a result, the as-prepared Pd/NH2-rGO catalyst exhibited excellent activity with a high initial turnover frequency of 767 h−1 and 100% hydrogen selectivity, which was predominant among the currently available pure Pd catalysts towards formic acid dehydrogenation under room temperature.

Background BRAF V600E mutation represents a group of colorectal carcinoma with poor prognosis. Although treatment strategies have been recommended after clinical investigations, the progression-free survival is short and unsatisfying. Case presentation Here, we present the case of a 28-year-old male diagnosed with ascending colon adenocarcinoma with multiple liver metastases. Treatment with FOLFIRI plus cetuximab and vemurafenib achieved partial response, following which the patient received conversion surgery with clear resection margin. After disease recurrence, he received combination treatment of nivolumab and regorafenib. Until August 2020, the patient achieved a partial response with more than 12 months progression-free survival. Circulating tumor DNA (ctDNA) was monitored during the patient's treatment. His ctDNA fractions exhibited significant elevation two months before disease progression. As a comparison, the tumor markers were not elevated until the patient was confirmed PD through CT imaging. Conclusion This case exemplifies how liquid biopsy and ctDNA sequencing can aid in real-time molecular characterization of tumors.

The Pd(0)-catalyzed coupling cyclization of 1,2-allenyl ketones with aryl halides to construct multisubstituted furan derivatives has been developed. Nevertheless, the detailed mechanism of this re...

Efficient synthesis of large-scale vertically aligned nitrogen-doped carbon nanotube arrays (VA-NCNTs) has always been a challenge. In this study, we proposed a facile way to obtain mass VA-NCNTs b...

Organic carbonates (OCs) are a class of compounds featured by a carbonyl flanked by two alkoxy/aryloxy groups. They exist in either linear or cyclic forms, of which the majority encountered in nature adopt a pentacyclic structure. However, the enzymatic basis for pentacyclic carbonate ring formation remains elusive. Here, we reported that a four-protein metabolon (AlmUII–UV) assembled by a small peptide protein (AlmUV) appends a reactive N-hydroxylcarbamoyl moiety to the decarboxylated aldgamycins followed by a non-enzymatic condensation to give the pentacyclic carbonate ring. Our results have documented an unprecedent mechanism for carbonate formation., Graphical abstract The pentacyclic carbonate ring of aldgamycins is formed by a four-protein metabolon assembled by a small peptide protein, which begins with the attachment of a reactive N-hydroxylcarbamoyl moiety followed by a non-enzymatic condensation.Image 1

Alumina supported bimetallic cobalt-iron oxide (Co3O4-Fe2O3/Al2O3) catalyst was prepared via co-impregnation of boehmite with the mixture solution of cobalt nitrate and iron nitrate followed by calcination in air. X-ray photoelectron spectroscopy and high-resolution transmission electron microscope analyses confirmed the existence of highly dispersed Co3O4 and Fe2O3 nanoparticles in the as-prepared catalysts. The catalytic activity of Co3O4-Fe2O3/Al2O3 was evaluated for the degradation of H-acid in aqueous solution by heterogeneous activation of peroxymonosulfate. The results indicated that the Co3O4-Fe2O3/Al2O3 catalyst exhibited an identical initial activity but much better recyclability than Co3O4/Al2O3 due to its low amount of metal leaching and possible redox circle of Co(II)/Co(III). Electron paramagnetic resonance spectroscopy and radical quenching experiments suggested that singlet oxygen (1O2) contributed much more than ·OH and SO4• to H-acid degradation, and the degradation mainly followed a nonradical reaction mechanism.

Major depression disorder is one of the most common psychiatric disorders that greatly threaten the mental health of a large population worldwide. Previous studies have shown that endoplasmic reticulum (ER) stress plays an important role in the pathophysiology of depression, and current research suggests that brain-derived neurotrophic factor precursor (proBDNF) is involved in the development of depression. However, the relationship between ER and proBDNF in the pathophysiology of depression is not well elucidated. Here, we treated primary hippocampal neurons of mice with corticosterone (CORT) and evaluated the relationship between proBDNF and ERS. Our results showed that CORT induced ERS and upregulated the expression of proBDNF and its receptor, Follistatin-like protein 4 (FSTL4), which contributed to significantly decreased neuronal viability and expression of synaptic-related proteins including NR2A, PSD95, and SYN. Anti-proBDNF neutralization and ISRIB (an inhibitor of the ERS) treatment, respective ly, protected neuronal viabilities and increased the expression of synaptic-related proteins in corticosterone-exposed neurons. ISRIB treatment reduced the expression of proBDNF and FSTL4, whereas anti-proBDNF treatment did not affect ERS markers (Grp78, p-PERK, ATF4) expression. Our study presented evidence that CORT-induced ERS negatively regulated the neuronal viability and the level of synaptic-related protein of primary neurons via the proBDNF/FSTL4 pathway.

Background Sepsis-associated encephalopathy (SAE) increases the mortality of septic patients, but its mechanism remains unclear. The present study aimed to investigate the roles of T lymphocytes, proBDNF, and their interaction in the pathogenesis of SAE. Methods Fear conditioning tests were conducted for cognitive assessment in the lipopolysaccharide (LPS, 5 mg kg−1)-induced septic mice. Meninges and peripheral blood were harvested for flow cytometry or qPCR. FTY720 and monoclonal anti-proBDNF antibody (McAb-proB) were used to investigate the effect of lymphocyte depletion and blocking proBDNF on the impaired cognitive functions in the septic mice. Results In the septic mice, cognitive function was impaired, the percentage of CD4+ T cells were decreased in the meninges (P = 0.0021) and circulation (P = 0.0222), and pro-inflammatory cytokines were upregulated, but the anti-inflammatory cytokines interleukin (IL)-4 (P < 0.0001) and IL-13 (P = 0.0350) were downregulated in the meninges. Lymphocyte depletion by intragastrically treated FTY720 (1 mg kg−1) for 1 week ameliorated LPS-induced learning deficit. In addition, proBDNF was increased in the meningeal (P = 0.0042) and peripheral (P = 0.0090) CD4+ T cells. Intraperitoneal injection of McAb-proB (100 μg) before LPS treatment significantly alleviated cognitive dysfunction, inhibited the downregulation of meningeal (P = 0.0264) and peripheral (P = 0.0080) CD4+ T cells, and normalized the gene expression of cytokines in the meninges. However, intra-cerebroventricular McAb-proB injection (1 μg) did not have such effect. Finally, exogenous proBDNF downregulated the percentage of CD4+ T cells in cultured splenocytes from septic mice (P = 0.0021). Conclusion Upregulated proBDNF in immune system promoted the pathogenesis of SAE through downregulating the circulating CD4+ T cells, limiting its infiltration into the meninges and perturbing the meningeal pro-/anti-inflammatory homeostasis.

Fusidane-type antibiotics are a group of triterpenoid antibiotics. They include helvolic acid, fusidic acid, and cephalosporin P1, among which fusidic acid has been used clinically. We have recentl...

High-purity hydrogen can be generated by hydrolysis of sodium borohydride and used for operating portable proton exchange membrane fuel cells. The monolith supported catalyst is suitable for practical NaBH4-based hydrogen generation system due to its simple reactor structure miniaturizing for small size applications and easy separation from the spent solution. In the present study, a structured catalyst was prepared by wash-coating the Al2O3 sol over the wall of cordierite monolith followed by depositing Pt using incipient wet impregnation method; then the monolithic catalysts were characterized by XRF, XRD, SEM, HRTEM and XPS. The catalytic activity of the Pt-based monolithic catalyst towards hydrolysis of NaBH4 was tested using a flow reactor under ambient conditions in an autothermal manner. The characterization results show that Pt nanoparticles are highly dispersed on the surface of the Al2O3-coated layer. A continuous and stable hydrogen generation can be obtained by feeding the reactant (10 wt% NaBH4–5 wt % NaOH) into the tube reactor loaded with the monolithic catalyst at feed rates of 0.5–2.0 mL min−1.

A strain was isolated from an activated sludge system and identified as Halomonas piezotolerans HN2 in this study, which is the first strain in H. piezotolerans with the capability of heterotrophic nitrification and aerobic denitrification. Strain HN2 showed the maximum nitrogen removal rate of 9.10 mg/L/h by utilizing ammonium at the salinity of 3.0%. Under saline environment, HN2 could remove nitrogen efficiently in neutral and slightly alkaline environments, with the carbon sources of sodium succinate and sodium citrate and the C/N ratio of 15-20, and the maximum removal efficiencies of ammonium, nitrite, and nitrate were 100%, 96.35%, and 99.7%, respectively. The genomic information revealed the presence of amoA, napA, and nosZ genes in strain HN2, and the target bands of nirS were obtained via a polymerase chain reaction. Therefore, we inferred that ammonium was mainly utilized for the growth of strain HN2 through assimilation, and another part of the initial ammonium was converted into nitrate through nitrification, and then into gaseous nitrogen through denitrification. This report indicated the potential application of strain HN2 and other nitrifying and denitrifying Halomonas strains in the removal of nitrogen pollution in marine-related environments and also implies the important role of Halomonas in the nitrogen cycle process of the ocean.

Ethnopharmacological relevance Eucommia ulmoides (E. ulmoides) leaves are included in the Chinese Pharmacopoeia, and are traditionally used to treat hypertension, obesity, diabetes, and other diseases. Numerous pharmacological studies have shown that E. ulmoides has a good effect on lowering blood lipids and can improve obesity and nonalcoholic fatty liver. Aim To study the mechanism of E. ulmoides leaves in regulating nonalcoholic fatty liver disease by combining prediction and validation. Methods Using network pharmacology, and molecular docking to predict E. ulmoides in regulating the action mechanism and potential active ingredients of nonalcoholic fatty liver, large hole adsorption resin enrichment active sites, in vitro experiments were performed to verify its fat-lowering effect and mechanism. Results The major components of E. ulmoides leaves exhibited good combination with lipid metabolism-regulating core proteins, particularly flavonoids. EUL 50 significantly reduced lipid accumulation, and increased PPARγ. Compared with the control group, the autophagy level increased after the administration of EUL 50. PPARγ decreased significantly after the addition of chloroquine (CQ, autophagy inhibitor). Conclusion The active ingredients in E. ulmoides leaves regulating nonalcoholic fatty liver disease are mainly flavonoids and phenolics. EUL 50 may play a role in lowering lipids by regulating PPARγ expression through inducing autophagy.

As a one-dimensional (1D) allotrope of carbon, carbon nanotubes (CNTs) have been widely investigated in the past two decades owing to their unique mechanical strength, large surface-to-volume ratio, and electrical properties. Graphene, a two-dimensional (2D) honeycomb nanostructure composed of single-layer carbon atoms, is also a promising choice for potential applications in energy storage. Interestingly, a fine combination of 1D and 2D building blocks that leads to the formation of a three-dimensional (3D) hierarchical structure could effectively inherit advantages of individual components and mitigate the aggregation and restacking of CNT and graphene, leading to unexpected properties for their outstanding application. Moreover, compared with other synthetic methods, the chemical vapor deposition (CVD) method is considered as a sophisticated approach for both laboratory research and industry production of nanocarbon materials or hybrids, and the carbon nanotube/graphene hybrids are expected to be a promising choice for high-performance applications in the future.

This study aimed to investigate the role and possible mechanism of β-asarone in regulating neuronal apoptosis and axonal regeneration. A scratch injury was applied to cell cultures of mouse primary cortical neurons to mimic neuronal injury. The neuronal apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling staining and western blot analysis of apoptosis-related proteins. The axonal regeneration was assessed by immunofluorescent staining of β-tubulin III and western blot analysis of axonal markers. In the results, β-asarone inhibited neuronal apoptosis and promoted axonal regeneration by suppressing tumor necrosis factor-α (TNF-α) expression in scratch-injured mouse neuronal cells. Research investigating the molecular mechanisms by which β-asarone inhibited TNF-α expression showed that, on the one hand, β-asarone suppressed the JNK/c-Jun pathway and thus transcriptionally inhibited TNF-α expression; on the other hand, β-asarone induced expression of UHRF1 that recruited DNMT1 to induce TNF-α promoter methylation and subsequently decreased the messenger RNA expression of TNF-α. In conclusion, β-asarone suppresses TNF-α expression through DNA methylation and c-Jun-mediated transcription modulation in scratch-injured neuronal cells.

N-doped carbon hollow microspheres (NCMs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor and N-dopant and ferrocene as both the catalyst and carbon precursor. It is shown that the size of the NCMs can be tuned just by changing the annealing temperature of the CVD furnace. The atomic percentage of nitrogen doping in NCMs could be achieved to 7.85% without sacrificing the hollow spherical structure. Probable growth mechanism of NCMs was proposed in this paper. The work reported here may pave a way for designing novel various atom-doped carbon microspheres.

N-doped well-aligned thin multiwall carbon nanotubes (CNTs) have been prepared by a facile water-assisted chemical vapor deposition (CVD) process using melamine as both the carbon precursor...

Metal–organic frameworks (MOFs) have gained significant attention as precursors for the fabrication of porous hybrid materials. However, a systematic investigation into the preparation of MOF-derived composites with high catalytic performance for hydrolysis of NaBH4 is very limited. In this work, we report the fabrication of Co@C composites using Co-MOF as the starting precursor. Physicochemical properties of the as-prepared Co@C catalysts are well characterized by XRD, BET, SEM, XPS, and HRTEM. The results of catalytic performance tests show that the Co@C-700 catalyst exhibits optimal activity among the Co@C catalysts prepared at different carbonization temperatures and retains 93.1% of its initial catalytic activity after five cycles. The cobalt nanoparticles are found to be highly dispersed and encapsulated in porous carbon, which might be responsible to the good stability of Co@C catalyst.

Intramolecular imino-ene reaction of 2 H-aziridine has been studied experimentally and computationally, demonstrating that (1) the concerted process takes place regioselectively on the alkene E-CH group; (2) the geometry of the N-linker impacts the reaction activation energy and diastereoselectivity significantly, with pyramidal alkyl amine as the linkage, an exclusive cis-product is achieved; (3) when the reaction has to occur with the Z-CH group, the cis-diastereoselectivity is solely observed regardless of the nature of the N-linkage.

Controlled growth of single-crystal high-quality ‘track-and-field ground’ shaped graphene domains and the morphological evolution from hexagonal to hexagram graphene domain even square and circular graphene domain has been achieved by low-pressure CVD on solid copper substrate, thereby demonstrating that the shape of the graphene grains can potentially be precisely tuned by optimizing growth parameters. The etching reaction of graphene has also been studied, and results show that a low flow rate of hydrogen (99.999%) is favorable to form hexagonal structure for the etching reaction of graphene due to the exist of oxygen or oxidizing impurities in hydrogen gas commonly used. Controlled growth and etching reaction of graphene determine the final shape of graphene domains and all these efforts contribute to the study of size and morphology and the growth mechanism of graphene domains. Keywords: Graphene, ‘Track-and-field ground’ shaped, Morphological evolution, Hexagram, Square-shaped, Etching, LPCVD

The present study was designed to investigate the mechanism of the traditional Chinese medicine Changqin NO. 1 on the amelioration of traumatic brain injury (TBI). Adult male C57BL/6J mice and newborn mice were used to generate a mouse TBI model and harvest primary neurons, respectively. The localizations of specific neural markers neuropilin-1 (Nrp-1), growth-associated protein-43 (GAP-43) and microtubule-associated protein Tau (Tau) were examined in brain tissues by immunohistochemistry. Terminal deoxynucleotidyl transferase dUTP nick end labeling apoptotic cell detection in tissue sections and the CCK-8 cell viability assay were performed to examine neuronal apoptosis. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were also carried out in this study. The association between long non-coding RNA (lncRNA) growth-arrest specific 5 (GAS5), miR-335 and RAS p21 GTPase activating protein 1 (Rasa1) was disclosed using the dual-luciferase reporter assay. Changqin NO. 1 inhibited TBI-induced neuronal apoptosis in vivo and in vitro. GAS5 functioned as a competing endogenous RNA (ceRNA) by sponging miR-335 to upregulate Rasa1 expression in mouse neuronal cells. Further investigations demonstrated that GAS5 promoted neuronal apoptosis following TBI via the miR-335/Rasa1 axis. In vivo experiments indicated that Changqin NO. 1 exerted neuroprotection during TBI via the GAS5/miR-335/Rasa1 axis. Changqin NO. 1 promoted neuroprotective effects by inhibiting neuronal apoptosis via the GAS5/miR-335/Rasa1 axis in TBI.

Herein, three-dimensional (3D) N-doped reduced graphene oxide (N-rGO) nanosheets were decorated with a uniform distribution of Co–Ni–S (CNS) nanoparticles to form the CNS/N-rGO composite as a sulfur host material for lithium–sulfur batteries. The CNS nanoparticles and N in CNS/N-rGO strongly interact with polysulfides, whereas graphene, as a conductive network, can improve its electrical conductivity. A CNS/N-rGO/sulfur composite cathode was prepared via the sulfur melting diffusion method. The electrochemical study showed that the CNS/N-rGO/sulfur cathode delivered an initial discharge capacity of 1430 mA h g−1 at a current density of 0.1C. Moreover, it retained a specific capacity of 685 mA h g−1 after 300 cycles at 0.5C with a coulombic efficiency of 98%, which was better than that of commercial rGO. This composite was used as a sulfur cathode for a lithium–sulfur battery, exhibiting excellent rate capability and remarkable performance in terms of long cycling stability.

Brown adipogenesis contributes to controlling systemic energy balance by enhancing glucose and lipid consumptions. We have previously reported chemical compound-induced brown adipocytes (ciBAs) directly converted from human dermal fibroblasts using a serum-free medium. In this study, genome-wide transcriptional analysis was performed in ciBAs in comparison with the control fibroblasts. A broad range of integrated gene expression was enhanced in functional groups including tricarboxylic acid cycle, electron transfer chain, triglycerides metabolism, fatty acid and glucose metabolism, and adaptive thermogenesis. The results suggested that the chemical conversion underwent metabolic and mitochondrial reprogramming closely associated with functions in brown/beige adipocytes. Moreover, we also compared the transcriptional changes to those of adipocyte browning in adipose tissue-derived mesenchymal stem cells (AdMSCs). Transcriptome analysis indicated that the same sets of metabolic and mitochondria-related genes were similarly changed in the adipocyte browning. Interestingly, ciBAs more expressed Ucp1, while AdMSC-derived adipocytes predominantly expressed Ucp2. UCP1 protein was also more expressed in ciBAs than in AdMSC-derived adipocytes. Based on the evidence that UCP1, but not UCP2, is responsible for adrenergic thermogenesis, ciBAs could be a promising model for human beige adipocytes applicable for basic research, drug development, and clinical uses.

Four new gallate derivatives—ornusgallate A, ent-cornusgallate A, cornusgallate B and C (1a, 1b, 2, 3)—were isolated from the wine-processed fruit of Cornus officinalis. Among them, 1a and 1b are new natural compounds with novel skeletons. Their chemical structures were elucidated by comprehensive spectroscopy methods including NMR, IR, HRESIMS, UV, ECD spectra and single-crystal X-ray diffraction analysis. The in vitro anti-inflammatory activities of all compounds were assayed in RAW 264.7 cells by assessing LPS-induced NO production. As the result, all compounds exhibited anti-inflammatory activities at attested concentrations. Among the tested compounds, compound 2 exhibited the strongest anti- inflammatory activity.

Over-expression of the pathway specific positive regulator gene is an effective way to activate silent gene cluster. In the curret study, the SARP family regulatory gene, vasR2, was over-expressed in strain Verrucosispora sp. NS0172 and the cryptic gene cluster responsible for the biosynthesis of pentaketide ansamycin was partially activated. Two tetraketides (1 and 2) and a triketide (3) ansamycins, together with five known compounds (4–8), were isolated and elucidated from strain NS0172OEvasR2. Their NMR data were completely assigned by analysis of their HR-ESI-MS and 1H, 13C NMR, HMQC, HMBC and 1H-1H COSY spectra.

Introduction: Previous studies showed that high density lipoprotein (HDL) can stimulate angiogenesis. However, the mechanisms by which HDL promotes angiogenesis remains unclear. Hypothesize: HDL may promote angiogenesis by regulating miRNAs expression. Methods: HDL was isolated from healthy subjects. Human umbilical vein endothelial cells (HUVECs) were cultured with vehicle or HDL (100 μg/ml), and the differential miRNAs expression were indentified by miRNA array and verified by qRT-PCR. HUVECs were treated with vehicle or HDL (100 μg/ml) with or without miRNAs mimic, endothelial cells proliferation, migration and tube formation were detected. The production of nitric oxide(NO) was measured. The expression and phosphorylation of endothelial nitric oxide synthase (eNOS) was determined. Results: The miRNAs profile of HDL-treated HUVECs is significantly different from control group. HDL significantly downregulated miR-24-3p expression. HDL significantly promoted HUVECs proliferation, migration and tube formation. HDL also significantly stimulated NO production and up-regulated the expression and phosphorylation of eNOS. However, HDL did not stimulated HUVECs proliferation, migration, tube formation and NO production as well as the expression and phosphorylation of eNOS after pretreated with miR-24-3p mimic. Conclusions: HDL can promote angiogenesis by suppressing miR-24-3p expression.

The innate physiological dormancy of Tulipa thianschanica seeds ensures its survival and regeneration in the natural environment. However, the low percentage of germination restricts the establishment of its population and commercial breeding. To develop effective ways to break dormancy and improve germination, some important factors of seed germination of T. thianschanica were tested, including temperature, gibberellin (GA3) and/or kinetin (KT), cold stratification and sowing depth. The percentage of germination was as high as 80.7% at a constant temperature of 4 &deg, C, followed by 55.6% at a fluctuating temperature of 4/16 &deg, C, and almost no seeds germinated at 16 &deg, C, 20 &deg, C and 16/20 &deg, C. Treatment with exogenous GA3 significantly improved the germination of seeds, but KT had a slight effect on the germination of T. thianschanica seeds. The combined treatment of GA3 and KT was more effective at enhancing seed germination than any individual treatment, and the optimal hormone concentration for the germination of T. thianschanica seeds was 100 mg/L GA3 + 10 mg/L KT. In addition, it took at least 20 days of cold stratification to break the seed dormancy of T. thianschanica. The emergence of T. thianschanica seedlings was the highest with 82.4% at a sowing depth of 1.5 cm, and it decreased significantly at a depth of &gt, 3.0 cm. This study provides information on methods to break dormancy and promote the germination of T. thianschanica seeds.

Constitutively expression of the pathway-specific activators is an effective method to activate silent gene clusters and improve natural product production. In this study, nine shunt products of aminoansamycins (1-9) were identified from a recombinant mutant strain S35-LAL by overexpressed the large-ATP-binding regulator of the LuxR family (LAL) gene aas1 in Streptomyces sp. S35. All the compounds showed no anti-microbial, anti-T3SS and cytotoxic activities.

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Discovering anticancer drugs that do not have adverse side effects has been a developing research field worldwide in recent decades. In this work, four previously undescribed cytotoxic diterpenoids were isolated from the aerial parts of Isodon excisoides. Interestingly, these four diterpenoids were two pairs of tautomers that were first reported in plants. Their structures were further elucidated using various spectroscopic methods. The tautomerization phenomenon and mechanism for these two pairs of tautomers were emphatically described. The theoretical simulation results indicated that the diterpene tautomerization is greatly related to certain factors, including the existence of a transition state, the change of bond length and the level of conversion energy; the tautomerization for the two pairs of tautomers is mainly caused by proton transfer. For bioassays, the cytotoxicities of the tautomers against five human cancer cell lines were also investigated. The results indicated that each of the four diterpenoids showed significant cytotoxicity in at least three cell lines and could serve as potential anticancer agents for further investigation.

Background Hydrogen peroxide has been widely used in Orthopaedics including Orthopaedic oncology, trauma and joint surgeries. However, we encountered an oxygen embolism and myoglobinuria after hydrogen peroxide was used to irrigate a septic hip arthroscopically. Case presentation A 61-year-old male patient with right hip septic arthritis underwent an arthroscopic hip washout and debridement. During the operation, the surgeon used 100 ml of 3% hydrogen peroxide to irrigate the joint cavity. Two minutes after irrigation, there was a transient decrease in oxygen saturation, heart rate and blood pressure, with significant subcutaneous emphysema around the wound. Concentrated urine was drained out 8 h after operation which resolved the following day. Post-operatively, the patient was managed in the intensive care unit for a pulmonary embolism and discharged without further complications. Conclusion Medical staff should be aware of the risk of oxygen embolism and be extremely careful when using hydrogen peroxide in patient care. Oxygen embolism following hydrogen peroxide use is rare, however, once encountered, it may bring serious consequences. Therefore, the use of hydrogen peroxide in closed spaces or arthroscopic procedures should be discontinued.

Computational studies were carried out to provide mechanistic insights into the Rh(I)-catalyzed activation of cyclopropenes and the detailed mechanistic pathways of [3+2+1] carbonylative carbocyclization of tethered ene- and yne-cyclopropenes. Computational results suggest that it is more favorable for the cyclopropene moiety of tethered ene-cyclopropenes to initially undergo heterolytic cleavage of a C-C σ-bond to form a vinyl Rh(I) carbenoid intermediate than to proceed through homolytic C-C σ-bond cleavage to generate a rhodacyclobutene intermediate. The yielded vinyl Rh(I) carbenoid intermediate could undergo cyclization to generate a Rh(III) metallacyclobutene intermediate, which could further lead to a thermodynamically more stable six-coordinated Rh(III) metallacycle intermediate in the presence of additional CO. Afterward, it is more feasible for the yielded six-coordinated Rh(III) metallacycle to sequentially undergo CO migratory insertion, cyclization, and reductive elimination to furnish the final cyclohexenone product. The origin of stereoselectivity of the product was also discussed. The proposed mechanistic pathway can also be applied to the Rh(I)-catalyzed carbonylative carbocyclization of tethered yne-cyclopropenes and vinyl cyclopropenes to produce phenol derivatives. The main mechanistic difference for the vinyl cyclopropene substrate is that the conversion of Rh(I) carbenoid intermediate to the Rh(III) metallacycle proceeds via intramolecular 6π electrocyclization.

The Warburg effect is a dominant phenotype of most tumor cells. Recent reports have shown that the Warburg effect can be reprogrammed by the tumor microenvironment. Lactic acidosis and glucose deprivation are the common adverse microenvironments in solid tumor. The metabolic reprogramming induced by lactic acid and glucose deprivation remains to be elucidated in glioblastoma. Here, we show that, under glucose deprivation, lactic acid can preserve high ATP levels and resist cell death in U251 cells. At the same time, we find that MCT1 and MCT4 are significantly highly expressed. The metabolic regulation factor HIF-1α decreased and C-MYC increased. Nuclear respiratory factor 1 (NRF1) and oxidative phosphorylation (OXPHOS)-related proteins (NDUFB8, ND1) are all distinctly increased. Therefore, lactic acid can induce lactate transport and convert the dominant Warburg effect to OXPHOS. Through bioinformatics analysis, the high expression of HIF-1α, MCT1 or MCT4 indicate a poor prognosis in glioblastoma. In addition, in glioblastoma tissue, HIF-1α, MCT4 and LDH are highly expressed in the interior region, and their expression is decreased in the lateral region. MCT1 can not be detected in the interior region and is highly expressed in the lateral region. Hence, different regions of glioblastoma have diverse energy metabolic pathways. Glycolysis occurs mainly in the interior region and OXPHOS in the lateral region. In general, lactic acid can induce regional energy metabolic reprogramming and assist tumor cells to adapt and resist adverse microenvironments. This study provides new ideas for furthering understanding of the metabolic features of glioblastoma. It may promote the development of new therapeutic strategies in GBM.

Brown adipocytes coordinate systemic energy metabolism associated with the pathogenesis of obesity and related metabolic diseases including type 2 diabetes. We have previously reported chemical compound-induced brown adipocytes (ciBAs) converted from human dermal fibroblasts without using transgenes. In this study, to reveal a precise molecular mechanism underlying the direct conversion and human adipocyte browning, we developed serum-free brown adipogenic medium (SFBAM) with an optimized chemical cocktail consisting of Rosiglitazone, Forskolin, and BMP7. During the direct conversion, treatment with BMP7 enhanced Ucp1 expression rather than the conversion efficiency in the absence of BMP signalling inhibitors. Moreover, treatment with a TGF-β signalling pathway inhibitor was no longer required in the serum-free medium, likely because the TGF-β pathway was already suppressed. SFBAM and the chemical cocktail efficiently converted human dermal fibroblasts into ciBAs within four weeks. The ciBAs exhibited increased mitochondrial levels, elevated oxygen consumption rate, and a response to β-adrenergic receptor agonists. Thus the ciBAs converted by the serum-free medium and the chemical cocktail provide a novel model of human brown (beige) adipocytes applicable for basic research, drug screening, and clinical applications.

The lanthanide aryloxides Ln(OAr)3(THF)2 (Ar = Ar1 = 2,6-tBu2-4-MeC6H2, Ln = Yb (1), Y (2); Ar = Ar2 = 2,6-iPr2C6H3, Ln = Y (3); Ar = Ar3 = 2,6-Me2C6H3, Ln = Y (4); Ar = Ar1, Ln = Sm (5), Nd (6)) could be served as highly efficient catalysts for the hydroboration of aldehydes and ketones with good functional group tolerance and excellent chemoselectivity. Computational studies were carried out to probe a feasible mechanism of the Ln-aryloxides catalyzed hydroboration of aldehydes/ketones.

The effects of both graphene nanoplatelets and reduced graphene oxide as additives to the negative active material in valve-regulated lead–acid batteries for electric bikes were investigated. Low-temperature performance, charge acceptance, cycle performance, and water loss were investigated. The test results show that the low-temperature performance, charge acceptance, and large-current discharge performance of the batteries with graphene additives were significantly improved compared to the control battery, and the cycle life under 100% depth of discharge condition was extended by more than 52% from 250 to 380 cycles. Meanwhile, the amount of water loss from the batteries with graphene changed only slightly compared with the control cells. The excellent performance of the batteries can be ascribed to the graphene promoting the negative-plate charge and discharge processes and suppressing the growth of lead sulfate crystals.

Background: Sleep disturbance is one of the major non-motor symptoms which cause the disability of Parkinson’s disease (PD) patients. Cystatin C (CysC) is a more sensitive biomarker than serum creatinine or estimated glomerular filtration rate. Previous studies have reported altered CysC levels in neurodegenerative disorders and sleep disorders. This study aimed to explore the correlations of serum CysC levels and objective sleep disturbances in early PD. Methods: We recruited 106 early PD patients and 146 age- and sex-matched controls. All participants underwent clinical investigation and video-polysomnography. Sleep parameters and serum levels of CysC were measured. Then, we investigated the relationships between CysC and clinical variables and objective sleep disturbances in early PD patients. Results: The mean serum level of CysC was significantly higher in patients with early PD (1.03 ± 0.19 mg/L) compared to controls (0.96 ± 0.15 mg/L, P = 0.009). There were significantly positive correlations between serum CysC levels and age (r = 0.334, P < 0.001), gender (r = 0.264, P = 0.013), and creatinine levels (r = 0.302, P = 0.018) in early PD patients. Increased serum CysC levels in early PD patients were significantly associated with higher apnea and hypopnea index (AHI) (r = 0.231, P = 0.017), especially hypopnea index (r = 0.333, P < 0.001). In early PD patients, elevated serum CysC levels were positively correlated with oxygen desaturation index (r = 0.223, P = 0.021), percentage of time spent at oxygen saturation (SaO2)

When the MLD method is used to determine the main chemical composition in the cement, it is assumed that the sum of the measured chemical composition is 100%. When the trace amount of heavy metal oxide is present in the cement sample without measuring, a positive error will be caused for main chemical composition results. On the other hand, according to the national standards GB/T 30760-2014 "technical specification for coprocessing of solid waste in cement kiln", also need to determine the heavy metals in cement. In this work, vanadium pentoxide, chromium oxide, copper oxide, zinc oxide, strontium oxide and barium oxide were measured by using melt beads for the determination of the main chemical components in cement. The calibration sample was calibrated using the standard addition – fusion method, using the theoretical MLD coefficient to calculate the standard dilution ratio. The method has been applied to the determination of heavy metal oxides in cement samples and achieved good results.

The SO42−/MxOy (M = Cu, Co, Fe) catalysts were prepared and applied to hydrogen production from methanolysis of sodium borohydride for the first time. The morphologies and properties of the as-prepared catalysts were characterized by XRD, BET, FT-IR, TEM and SEM-EDX techniques. Under our experimental conditions, SO42−/CuO exhibits much higher catalytic activity than those of SO42−/CoO and SO42−/Fe2O3 catalysts and follows the order of SO42−/CuO > SO42−/CoO > SO42−/Fe2O3, which is opposite to order of BET surface area, implying that the methanolysis of sodium borohydride is not a structure-sensitive reaction. It can be inferred that both acidic and metallic sites are responsible for the high catalytic performance of the SO42−/MxOy catalysts towards NaBH4 methanolysis. In addition, the effects of the concentrations of NaBH4 and methanol, catalyst dosage, and reaction temperature on the hydrogen generation rate have been investigated using SO42−/CuO as catalyst. The SO42−/CuO-catalyzed methanolysis reaction follows a power law, i.e. r = A·exp (−13135/RT)·[NaBH4]1.01·[CH3OH]1.60·[Catalyst]0.52. The apparent activation energy was calculated to be 13.13 kJ/mol.