Synthesis of nucleoside oligophosphates by electrophilic activation of phosphorothioate.

We herein report a new synthetic method for nucleoside oligophosphates based on electrophilic activation of 5'-phosphorothioate nucleotides. The treatment of phosphorothioate with 2,4-dinitrochlorobenzene (DNCB) efficiently afforded the key activated species, electrophilic thioester nucleotides (EPT-Ns), which were coupled with various phosphate reagents to afford the target nucleoside oligophosphates, including an mRNA cap analog.

Synthesis of 8-Alkoxy-5H-isochromeno[3,4-c]isoquinolines and 1-Alkoxy-4-arylisoquinolin-3-ols through Rh(III)-Catalyzed C-H Functionalization of Benzimidates with 4-Diazoisochroman-3-imines and 4-Diazoisoquinolin-3-ones.

Rh(III)-catalyzed C-H activation/annulation of benzimidates with 4-diazoisochroman-3-imines furnished 8-alkoxy-5H-isochromeno[3,4-c]isoquinolines in moderate to excellent yields with a broad range of substrate scope. The reaction was carried out under mild reaction conditions and could be scaled up with practical usage. Similar reaction between benzimidates and 4-diazoisoquinolin-3-ones provided 1-alkoxy-4-arylisoquinolin-3-ols in excellent yields. Moreover, the synthesized products could be conveniently transformed to the corresponding heterocycles with a 1,8-naphthyridinone or isochromenopyridinone core, which are privileged structures in medicinal chemistry.

TfOH-promoted synthesis of 4,5-dihydrooxazolo[5,4-c]isoquinolines via formal [3 + 2] cycloaddition of 4-diazoisoquinolin-3-one and benzonitriles.

A facile and efficient method for the synthesis of novel 2-substituted 4-tosyl-4,5-dihydrooxazolo[5,4-c]isoquinolines from 4-diazoisoquinolin-3-ones and nitriles is reported. The reaction proceeded through a TfOH-promoted formal [3 + 2] cycloaddition and the products could be conveniently converted to 2-aryloxazolo[5,4-c]isoquinolines and the subsequent 2-(oxazolo[5,4-c]isoquinolin-2-yl)phenol which emitted bright green light in dilute dichloromethane solution and in solid form as well. Simple operation, metal-free and mild reaction conditions, short reaction time and broad substrate scope are the prominent features of this methodology.

General Approach To Construct Azepino[2,3-b:4,5-b']diindoles, Azocino[2,3-b:4,5-b']diindoles, and Azonino[2,3-b:4,5-b']diindoles via Rh(II)-Catalyzed Reactions of 3-Diazoindolin-2-imines with 3-(Bromoalkyl)indoles.

Rh(II)-catalyzed reactions of 3-diazoindolin-2-imines with 3-(2-bromoethyl)indoles, 3-(3-bromopropyl)indoles, and 3-(4-bromobutyl)indoles, followed by treatment with 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) in a one-pot operation furnished azepino[2,3-b:4,5-b']diindoles, azocino[2,3-b:4,5-b']diindoles, and azonino[2,3-b:4,5-b']diindoles, respectively. Structural uniqueness of the products, broad substrate scope, mild reaction conditions, and readily available starting materials are the merits of this approach.

Palladium-Catalyzed Synthesis of 3-Haloindol-2-amines from 3-Diazoindolin-2-imines and Alkyl Halides.

Synthetically valuable 3-haloindol-2-amines were prepared from readily available 3-diazoindolin-2-imines and a variety of alkyl halides through the palladium-catalyzed reaction. The broad substrate scope of both diazo compounds and alkyl halides, mild reaction conditions, and high efficiency are the main characters of this method. The synthesized 3-haloindol-2-amines can be conveniently transformed to more complex indole derivatives.

Copper-Catalyzed Syntheses of 3-Allyl-3-arylthioindolin-2-imines and 3-Allenyl-3-arylthioindolin-2-imines from 3-Diazoindolin-2-imines.

3-Allyl-3-arylthioindolin-2-imines and 3-allenyl-3-arylthioindolin- 2-imines were synthesized via the copper-catalyzed reaction of 3-diazoindolin-2-imines with allyl and propargyl aryl sulfides, respectively. The formation of a sulfonium ylide through the reaction of allyl or propargyl aryl sulfides with copper carbene species generated from 3-diazoindolin-2-imines and subsequent [2,3]-sigmatropic rearrangement should be involved in the cascade process. The procedure is general and highly efficient for the construction of these 3,3-disubstituted indoline derivatives.

Preparation of 3-Aryl-2-aminoindoles via Rhodium-Catalyzed Coupling Reaction between 2-Arylpyridines and 3-Diazoindolin-2-imines.

Rhodium-catalyzed coupling reaction of 3-diazoindolin-2-imines with 2-arylpyridines, 2-phenylpyrimidines, or 1-phenylpyrazoles furnished the corresponding 3-aryl-2-aminoindoles in moderate to excellent yields. A variety of functional groups were tolerant to the reaction conditions.

Nomogram for predicting overall survival after curative gastrectomy using inflammatory, nutritional and pathological factors.

PURPOSE: To establish a nomogram for predicting the overall survival (OS) in patients with gastric cancer (GC) based on inflammatory, nutritional and pathological factors. METHODS: GC patients underwent curative gastrectomy from January 2012 to June 2017 in our hospital were included, and were classified into training set and validation set with a ratio of 7:3. Then variables associated with OS were analyzed using univariate and multivariate Cox regression analysis. Nomograms predicting OS were built using variables from multivariable Cox models. Finally, Kaplan-Meier curve and Log-rank test were also conducted to analyze the 1-yr, 3-yr and 5-yr OS to validate the efficiency of risk stratification of the nomogram. RESULTS: A total of 366 GC patients were included. After univariate and multivariate Cox regression analysis, age (HR = 1.52, 95% CI = 1.01-2.30, P = 0.044), CA50 (HR = 1.90, 95% CI = 1.12-3.21, P = 0.017), PNI (HR = 1.65, 95% CI = 1.13-2.39, P = 0.009), SII (HR = 1.46, 95% CI = 1.03-2.08, P = 0.036), T stage (HR = 2.26, 95% CI = 1.01-5.05, P = 0.048; HR = 7.24, 95% CI = 3.64-14.40, P < 0.001) were independent influencing factors on the survival time of GC patients. Five factors including CEA, prognostic nutritional index (PNI), systemic immune-inflammation index (SII), ln (tumor size), T stage, and N stage were identified and entered the nomogram, which showed good discrimination and calibration in both sets. On internal validation, 1-yr, 3-yr and 5-yr nomogram demonstrated a good discrimination with an area under the ROC curve (AUC) of 0.77, 0.84 and 0.86, respectively. The AUC for 1-yr, 3-yr and 5-yr nomogram in validation set was 0.77, 0.79 and 0.81, respectively. The OS in low risk group of training cohort and validation cohort was significantly higher than that of intermediate risk group and high risk group, respectively. CONCLUSIONS: We established a nomogram based on PNI, SII and pathological factors for predicting OS in GC patients. In addition, its efficiency was validated by validation set and stratified analysis.

Intracellular delivery of antisense oligonucleotides by tri-branched cyclic disulfide units.

Therapeutic oligonucleotides, such as antisense DNA, show promise in treating previously untreatable diseases. However, their applications are still hindered by the poor membrane permeability of naked oligonucleotides. Therefore, it is necessary to develop efficient methods for intracellular oligonucleotide delivery. Previously, our group successfully developed disulfide-based Membrane Permeable Oligonucleotides (MPON), which achieved enhanced cellular uptake and gene silencing effects through an endocytosis-free uptake mechanism.  Herein, we report a new molecular design for the next generation of MPON, called trimer MPON. The trimer MPON consists of a tri-branched backbone, three α-lipoic acid units, and a spacer linker between the oligonucleotides and tri-branched cyclic disulfide unit. We describe the design, synthesis, and functional evaluation of the trimer MPON, offering new insights into the molecular design for efficient oligonucleotide delivery.

Exploring the Pathogenesis and Treatment of PSD from the Perspective of Gut Microbiota.

Post-stroke depression (PSD) is a psychological disease that can occur following a stroke and is associated with serious consequences. Research on the pathogenesis and treatment of PSD is still in the infancy stage. Patients with PSD often exhibit gastrointestinal symptoms; therefore the role of gut microbiota in the pathophysiology and potential treatment effects of PSD has become a hot topic of research. In this review, describe the research on the pathogenesis and therapy of PSD. We also describe how the gut microbiota influences neurotransmitters, the endocrine system, energy metabolism, and the immune system. It was proposed that the gut microbiota is involved in the pathogenesis and treatment of PSD through the regulation of neurotransmitter levels, vagal signaling, hypothalamic-pituitary-adrenal axis activation and inhibition, hormone secretion and release, in addition to immunity and inflammation.

Hotspots Reduction for GALS NoC Using a Low-Latency Multistage Packet Reordering Approach.

Traffic splitting enabled by Globally Asynchronous Locally Synchronous (GALS) Network-on-chip (NoC) brings multipath routing capability, which significantly increases link bandwidth at the cost of out-of-order packet delivery. Solving the packet reordering problem is one of the keys to ensure the quality of service (QoS) for NoC. However, traditional packet reordering approaches rely on local reorder buffer, causing on-chip hotspots, which aggravates chip aging and even leads to interconnection failures. In this paper, we present a multistage packet reordering (MPR) approach, which cannot only reduce the transmission latency but also effectively reduces hotspots caused by local reordering. Specifically, we propose multistage reordering buffer (MRB) by reusing channel buffers for implementing MPR. Experimental results show that our proposed approach achieved improved thermal efficiency with reduced hardware resource consumption.

Polyphenols: Natural food grade biomolecules for treating neurodegenerative diseases from a multi-target perspective.

As natural functional bioactive ingredients found in foods and plants, polyphenols play various antioxidant and anti-inflammatory roles to prevent the development of disease and restore human health. The multi-target modulation of polyphenols provides a novel practical therapeutic strategy for neurodegenerative diseases that are difficult to treat with traditional drugs like glutathione and cholinesterase inhibitors. This review mainly focuses on the efficacy of polyphenols on ischemic stroke, Parkinson's disease and Alzheimer's disease, including in vivo and in vitro experimental studies. It is further emphasized that polyphenols exert neuroprotective effects primarily through inhibiting production of oxidative stress and inflammatory cytokines, which may be the underlying mechanism. However, polyphenols are still rarely used as medicines to treat neurodegenerative diseases. Due to the lack of clinical trials, the mechanism of polyphenols is still in the stage of insufficient exploration. Future large-scale multi-center randomized controlled trials and in-depth mechanism studies are still needed to fully assess the safety, efficacy and side effects of polyphenols.

Cap analogs with a hydrophobic photocleavable tag enable facile purification of fully capped mRNA with various cap structures.

Starting with the clinical application of two vaccines in 2020, mRNA therapeutics are currently being investigated for a variety of applications. Removing immunogenic uncapped mRNA from transcribed mRNA is critical in mRNA research and clinical applications. Commonly used capping methods provide maximum capping efficiency of around 80-90% for widely used Cap-0- and Cap-1-type mRNAs. However, uncapped and capped mRNA possesses almost identical physicochemical properties, posing challenges to their physical separation. In this work, we develop hydrophobic photocaged tag-modified cap analogs, which separate capped mRNA from uncapped mRNA by reversed-phase high-performance liquid chromatography. Subsequent photo-irradiation recovers footprint-free native capped mRNA. This approach provides 100% capping efficiency even in Cap-2-type mRNA with versatility applicable to 650 nt and 4,247 nt mRNA. We find that the Cap-2-type mRNA shows up to 3- to 4-fold higher translation activity in cultured cells and animals than the Cap-1-type mRNA prepared by the standard capping method.

Efficient photocatalytic decomposition of perfluorooctanoic acid by indium oxide and its mechanism.

Perfluorooctanoic acid (C(7)F(15)COOH, PFOA) has increasingly attracted worldwide concerns due to its global occurrence and resistance to most conventional treatment processes. Though TiO(2)-based photocatalysis is strong enough to decompose most organics, it is not effective for PFOA decomposition. We first find that indium oxide (In(2)O(3)) possesses significant activity for PFOA decomposition under UV irradiation, with the rate constant about 8.4 times higher than that by TiO(2). The major intermediates of PFOA were C(2)-C(7) shorter-chain perfluorocarboxylic acids, implying that the reaction proceeded in a stepwise manner. By using diffuse reflectance infrared Fourier transform spectroscopy, (19)F magic angle spinning nuclear magnetic resonance, and electron spin resonance, we demonstrate that the terminal carboxylate group of PFOA molecule tightly coordinates to the In(2)O(3) surface in a bidentate or bridging configuration, which is beneficial for PFOA to be directly decomposed by photogenerated holes of In(2)O(3) under UV irradiation, while PFOA coordinates to TiO(2) in a monodentate mode, and photogenerated holes of TiO(2) preferentially transform to hydroxyl radicals, which are inert to react with PFOA. PFOA decomposition in wastewater was inhibited by bicarbonate and other organic matters; however, their adverse impacts can be mostly avoided via pH adjustment and ozone addition.

Ferroptosis in Rheumatoid Arthritis: A Potential Therapeutic Strategy.

Ferroptosis is one of the newly discovered forms of cell-regulated death characterized by iron-dependent lipid peroxidation. Extensive research has focused on the roles of ferroptosis in tumors, blood diseases, and neurological diseases. Some recent findings have indicated that ferroptosis may also be related to the occurrence and development of inflammatory arthritis. Ferroptosis may be a potential therapeutic target, and few studies in vitro and animal models have shown implications in the pathogenesis of inflammatory arthritis. This mini review discussed the common features between ferroptosis and the pathogenesis of rheumatoid arthritis (RA), and evaluated therapeutic applications of ferroptosis regulators in preclinical and clinical research. Some critical issues worth paying attention to were also raised to guide future research efforts.

Comparison of copper and aluminum doped cobalt ferrate nanoparticles for improving biohydrogen production.

Two various materials, copper and aluminum doped cobalt ferrite nanoparticles (NPs) were fabricated for investigating their effects of addition amounts on hydrogen (H2) synthesis and process stability. CoCu0.2Fe1.8O4NPs enhanced H2 production more than CoAl0.2Fe1.8O4 NPs under same condition. The highest H2 yield of 212.25 ml/g glucose was found at optimal dosage of 300 mg/L CoCu0.2Fe1.8O4 NPs, revealing the increases of 43.17% and 6.67% compared with the control without NPs and 300 mg/L CoAl0.2Fe1.8O4 NPs groups, respectively. NPs level of more than 400 mg/L inhibited H2 generation. Further investigations illustrated that CoCu0.2Fe1.8O4 NPs were mainly distributed on extracellular polymer substance while CoAl0.2Fe1.8O4 NPs were mostly enriched on cell membrane, which facilitated electron transfer behavior. Community structure composition demonstrated that CoCu0.2Fe1.8O4 and CoAl0.2Fe1.8O4 separately caused a 9.67% and 9.03% increase in Clostridium sensu stricto 1 compared with the control reactor without NPs exposure.

Nickel-Cobalt Oxide Nanoparticle-Induced Biohydrogen Production.

The positive effects of metal oxide nanoparticles (NPs) on dark fermentation (DF) for biohydrogen synthesis have been increased, and the mechanism still needs to be further revealed. In this study, nickel-cobalt oxide (NiCo2O4) NPs were prepared to increase H2 yield via DF. The highest (259.67 mL/g glucose) and the lowest (188.14 mL/g glucose) yields were achieved at 400 and 800 mg/L NiCo2O4 NPs added, respectively, with their corresponding 33.97% increase and 2.93% decrease compared with the control yield (193.82 mL/g glucose). Meanwhile, the microbial community further confirmed that NiCo2O4 NPs increased the abundance of the dominant H2-producing Clostridium sensu stricto 1 by 23.05%. The gene prediction also showed that NiCo2O4 NPs increased the abundance of genes encoding the rate-limiting enzyme pyruvate kinase in glycolysis, thus increasing the substrate conversion. Moreover, the gene abundance of key enzymes directly related to H2 evolution was also increased at different levels.

Complete Chemical Synthesis of Minimal Messenger RNA by Efficient Chemical Capping Reaction.

Site-specific chemical modification of mRNA can improve its translational efficiency and stability. For this purpose, it is desirable to develop a complete chemical synthesis method for chemically modified mRNA. The key is a chemical reaction that introduces a cap structure into the chemically synthesized RNA. In this study, we developed a fast and quantitative chemical capping reaction between 5'-phosphorylated RNA and N7-methylated GDP imidazolide in the presence of 1-methylimidazole in the organic solvent dimethyl sulfoxide. It enabled quantitative preparation of capping RNA within 3 h. We prepared chemically modified 107-nucleotide mRNAs, including N6-methyladenosine, insertion of non-nucleotide linkers, and 2'-O-methylated nucleotides at the 5' end and evaluated their effects on translational activity in cultured HeLa cells. The results showed that mRNAs with non-nucleotide linkers in the untranslated regions were sufficiently tolerant to translation and that mRNAs with the Cap_2 structure had higher translational activity than those with the Cap_0 structure.

Immunogenicity of Inactivated SARS-CoV-2 Vaccines in Patients With Rheumatoid Arthritis: A Case Series.

Objectives: Attenuated humoral response to mRNA SARS-CoV-2 vaccines has been reported in some patients with autoimmune disease, e.g., rheumatoid arthritis (RA). However, data of immune responses to inactivated SARS-CoV-2 vaccine in the RA population are still unknown. Herein, the safety and immunogenicity of inactivated SARS-CoV-2 vaccines in RA patients were analyzed. Methods: Seventy five RA patients and 26 healthy controls (HC) were respectively recruited from Yunnan Provincial Hospital of Traditional Chinese Medicine and the community in Kunming city. Neutralizing Antibody (NAb) Test ELISA kit was used to measure the percentage of inhibition. AKA (anti-keratin antibody) positivity was detected using indirect immunofluorescence. Rheumatoid factor (RF)-IgA was detected by ELISA. RF-IgG, RF-IgM, and anti-cyclic citrullinated peptide (CCP) antibodies were measured by chemiluminescence. ESR (erythrocyte sedimentation rate) was detected by ESR analyzer. C-RP (c-reactive protein) was detected by immunoturbidimetry. NEUT% (percentage of neutrophils) and LYMPH% (percentage of percentage) were calculated by a calculation method. Results: Compared with the HC group, the percentage of inhibition was significantly lower in RA patients receiving two doses of vaccines. Vaccines-induced percentage of inhibition was the lowest in RA patients who had not been vaccinated. In total 80.77% of the HC group had a percentage of inhibition ≧20%, compared with 45.24% of vaccinated RA patients and 6.06% of unvaccinated RA patients. Spearman correlation analysis revealed that antibody responses to SARS-CoV-2 did not differ between RA patients according to their age and disease duration. Furthermore, the results showed that no correlation was found between the percentage of inhibition and indices for RA, including RF-IgA, IgG, IgM; anti-CCP antibody; ESR; C-RP; NEUT% and LYMPH%. Conclusion: Our study showed inactivated vaccine-induced SARS-COV-2 antibody responses differ in RA patients and healthy subjects, emphasizing the importance of a third or fourth vaccination in RA patients.

Third dose of anti-SARS-CoV-2 inactivated vaccine for patients with RA: Focusing on immunogenicity and effects of RA drugs.

Objectives: To evaluate the immunogenicity of the third dose of inactivated SARS-CoV-2 vaccine in rheumatoid arthritis (RA) patients and explore the effect of RA drugs on vaccine immunogenicity. Methods: We recruited RA patients (n = 222) and healthy controls (HC, n = 177) who had been injected with a third dose of inactivated SARS-CoV-2 vaccine, and their neutralizing antibody (NAb) titer levels were assessed. Results: RA patients and HC were age- and gender-matched, and the mean interval between 3rd vaccination and sampling was comparable. The NAb titers were significantly lower in RA patients after the third immunization compared with HC. The positive rate of NAb in HC group was 90.4%, while that in RA patients was 80.18%, and the difference was significant. Furthermore, comparison of NAb titers between RA treatment subgroups and HC showed that the patients in the conventional synthetic (cs) disease-modifying anti-rheumatic drugs (DMARDs) group exhibited no significant change in NAb titers, while in those receiving the treatment of biological DMARDs (bDMARDs), Janus Kinase (JAK) inhibitors, and prednisone, the NAb titers were significantly lower. Spearman correlation analysis revealed that NAb responses to SARS-CoV-2 in HC did differ significantly according to the interval between 3rd vaccination and sampling, but this finding was not observed in RA patients. In addition, NAb titers were not significantly correlated with RA-related laboratory indicators, including RF-IgA, RF-IgG, RF-IgM, anti-CCP antibody; C-RP; ESR; NEUT% and LYMPH%. Conclusion: Serum antibody responses to the third dose of vaccine in RA patients were weaker than HC. Our study will help to evaluate the efficacy and safety of booster vaccination in RA patients and provide further guidance for adjusting vaccination strategies.