Ag-Catalyzed Switchable Synthesis of Site-Specifically Functionalized Pyrroles via Azafulvenium Intermediates.

Here, we present a versatile, silver-catalyzed multi-auto-tandem reaction involving enamines, alkynals, and nucleophiles, utilizing the highly reactive intermediate azafulvenium. This method allows for flexible and switchable regiodivergent reactions through either intermolecular or intramolecular nucleophilic attacks, which can be controlled by adjusting the catalytic conditions. A range of site-specific functionalized or polycyclic fused pyrrole products were efficiently produced with a high level of chemocontrol.

Bioactive atropisomers: Unraveling design strategies and synthetic routes for drug discovery.

Atropisomerism, an expression of axial chirality caused by limited bond rotation, is a prominent aspect within the field of medicinal chemistry. It has been shown that atropisomers of a wide range of compounds, including established FDA-approved drugs and experimental molecules, display markedly different biological activities. The time-dependent reversal of chirality in atropisomers poses complexity and obstacles in the process of drug discovery and development. Nonetheless, recent progress in understanding atropisomerism and enhanced characterization methods have greatly assisted medicinal chemists in the effective development of atropisomeric drug molecules. This article provides a comprehensive review of their special design thoughts, synthetic routes, and biological activities, serving as a reference for the synthesis and biological evaluation of bioactive atropisomers in the future.

Catalytic Atroposelective Synthesis of Axially Chiral Azomethine Imines and Neuroprotective Activity Evaluation.

Azomethine imines, as a prominent class of 1,3-dipolar species, hold great significance and potential in organic and medicinal chemistry. However, the reported synthesis of centrally chiral azomethine imines relies on kinetic resolution, and the construction of axially chiral azomethine imines remains unexplored. Herein, we present the synthesis of axially chiral azomethine imines through copper- or chiral phosphoric acid catalyzed ring-closure reactions of N'-(2-alkynylbenzylidene)hydrazides, showcasing high efficiency, mild conditions, broad substrate scope, and excellent enantioselectivity. Furthermore, the biological evaluation revealed that the synthesized axially chiral azomethine imines effectively protect dorsal root ganglia (DRG) neurons by inhibiting apoptosis induced by oxaliplatin, offering a promising therapeutic approach for chemotherapy-induced peripheral neuropathy (CIPN). Remarkably, the (S)- and (R)-atropisomers displayed distinct neuroprotective activities, underscoring the significance of axial stereochemistry.

Healing strength of tendon repair with or without knots between two tendon ends and histological changes in a chicken model.

We studied the healing strength and histological changes of digital flexor tendons repaired using Kessler (core suture knots placed over the tendon surface) and modified Kessler (core suture knots placed between two tendon ends) in 31 long toes of chicken. Four weeks after surgery, the healing tendons were measured in a tensile testing machine, and the adhesion formation and histological changes were observed. The strength of the Kessler repairs was significantly greater than that of the modified Kessler repairs with a 35% mean difference. No significant difference was found between the adhesion scores of the tendons repaired with both techniques. In histological sections, the arrangement of collagen fibers in the modified Kessler repair group was more disordered. We conclude that the tendons repaired with the Kessler method are stronger than those with the modified Kessler technique. The knots between tendon ends are detrimental to the early healing strength of digital flexor tendons.

Canadine inhibits epithelial mesenchymal transformation of HPV-negative cervical cancer.

Although the majority of the population will be protected due to the advent and widespread use of the HPV vaccine, the treatment of cervical cancer for all causes, including HPV-negative cervical cancer, is still worthy of further research. The focal point of this study was Canadine's inhibition of epithelial-mesenchymal transformation (EMT) in cervical cancer. Immunoblotting, wound healing and tumor invasion experiments showed that low concentration of Canadine could inhibit the EMT process, proliferation and migration of HT-3 cells (HPV-negative cell line). Combined with GEO database, it was found that the expression levels of several genes highly expressed in cervical tumor tissues could be inhibited by Canadine, especially MAGEA3. Further experiments confirmed that the inhibition of Canadine on MAGEA3 protein increased with time. The small interference and overexpression plasmid of MAGEA3 were designed and verified. In HT-3 cells, when MAGEA3 levels were directly decreased, mesenchymal phenotypic markers were decreased and epithelial phenotypic markers were increased. The opposite result was obtained by overexpression of MAGEA3. In addition, the inhibition of EMT due to the reduction of endogenous MAGEA3 by Canadine was also offset by the overexpression of exogenous MAGEA3. The study concludes that Canadine inhibits EMT of cervical cancer by inhibiting MAGEA3.

Organocatalytic Asymmetric [4 + 2] Cyclization of Azadienes with Azlactones: Access to Chiral 3-Amino-δ-Lactams Derivatives.

Herein, a series of chiral δ-lactam frameworks have been synthesized and catalyzed by chiral phosphoric acid (CPA) utilizing two kinds of open-chain aza-dienes and azlactones derived from amino acids. This powerful [4 + 2] annulation produces a broad substrate scope with functional group tolerance in yield up to 97% with up to 98:2 er. Moreover, a facile scale-up and straightforward conversion to diversely substituted products verify the synthetic utility of this method featuring good compatibility and high efficiency.

Cross-Platform Transcriptomic Data Integration, Profiling, and Mining in Vibrio cholerae.

A large number of transcriptome studies generate important data and information for the study of pathogenic mechanisms of pathogens, including Vibrio cholerae. V. cholerae transcriptome data include RNA-seq and microarray: microarray data mainly include clinical human and environmental samples, and RNA-seq data mainly focus on laboratory processing conditions, including different stresses and experimental animals in vivo. In this study, we integrated the data sets of both platforms using Rank-in and the Limma R package normalized Between Arrays function, achieving the first cross-platform transcriptome data integration of V. cholerae. By integrating the entire transcriptome data, we obtained the profiles of the most active or silent genes. By transferring the integrated expression profiles into the weighted correlation network analysis (WGCNA) pipeline, we identified the important functional modules of V. cholerae in vitro stress treatment, gene manipulation, and in vitro culture as DNA transposon, chemotaxis and signaling, signal transduction, and secondary metabolic pathways, respectively. The analysis of functional module hub genes revealed the uniqueness of clinical human samples; however, under specific expression patterning, the Δhns, ΔoxyR1 strains, and tobramycin treatment group showed high expression profile similarity with human samples. By constructing a protein-protein interaction (PPI) interaction network, we discovered several unreported novel protein interactions within transposon functional modules. IMPORTANCE We used two techniques to integrate RNA-seq data for laboratory studies with clinical microarray data for the first time. The interactions between V. cholerae genes were obtained from a global perspective, as well as comparing the similarity between clinical human samples and the current experimental conditions, and uncovering the functional modules that play a major role under different conditions. We believe that this data integration can provide us with some insight and basis for elucidating the pathogenesis and clinical control of V. cholerae.

M2 Macrophage Membrane-Mediated Biomimetic-Nanoparticle Carrying COX-siRNA Targeted Delivery for Prevention of Tendon Adhesions by Inhibiting Inflammation.

Tendon adhesion is the most common outcome of tendon or tendon-to-bone healing after injury. Our group developed a hydrogel-nanoparticle sustained-release system previously to inhibit cyclooxygenases (COXs) expression and consequently prevent tendon adhesion and achieved satisfactory results. However, effective treatment of multiple tendon adhesions is always a challenge in research on the prevention of tendon adhesion. In the present study, an M2M@PLGA/COX-siRNA delivery system is successfully constructed using the cell membranes of M2 macrophages and poly (lactic-co-glycolic acid) (PLGA) nanoparticles. Targeting properties and therapeutic effects are observed in mice or rat models of flexor digitorum longus (FDL) tendon injury combined with rotator cuff injury. The results showed that the M2M@PLGA/COX-siRNA delivery system has low toxicity and remarkable targeting properties to the injured areas. Treatment with the M2M@PLGA/COX-siRNA delivery system reduced the inflammatory reaction and significantly improved tendon adhesion in both the FDL tendon and rotator cuff tissues. These findings indicate that the M2M@PLGA delivery system can provide an effective biological strategy for preventing multiple tendon adhesions.

Palladium-catalyzed asymmetric [4+2] annulation of vinyl benzoxazinanones with pyrazolone 4,5-diones to access spirobenzoxazine frameworks.

Herein, a palladium-catalyzed general synthetic strategy to access an attractive and decorated set of chiral spiro derivatives of benzoxazine compounds is unveiled utilizing vinyl benzoxazinanones reacted with pyrazolone 4,5-diones, which extends the application of vinyl benzoxazinanones with ketones. This asymmetric catalytic [4+2] cycloaddition reaction demonstrates a broad substrate scope with functional group tolerance in yields of up to 76% and up to 96% ee. A facile scale-up and straightforward conversion to diversely substituted products verify the synthetic utility of this method.

Biological and Mechanical Factors and Epigenetic Regulation Involved in Tendon Healing.

Tendons are an important part of the musculoskeletal system. Connecting muscles to bones, tendons convert force into movement. Tendon injury can be acute or chronic. Noticeably, tendon healing requires a long time span and includes inflammation, proliferation, and remodeling processes. The mismatch between endogenous and exogenous healing may lead to adhesion causing further negative effects. Management of tendon injuries and complications such as subsequent adhesion formation are still challenges for clinicians. Due to numerous factors, tendon healing is a complex process. This review introduces the role of various biological and mechanical factors and epigenetic regulation processes involved in tendon healing.

Genome-wide identification and characterization of the HSP gene superfamily in apple snails (Gastropoda: Ampullariidae) and expression analysis under temperature stress.

Apple snails from the family Ampullariidae have become economically important due to several species mainly from the genus Pomacea being invasive. The heat shock proteins (HSPs), which are important molecular chaperones for species responding to various stresses, have been proved to play critical roles in adapting harsh environments in the invasive apple snails. The recent release of the genomes of Pomacea canaliculata, Pomacea maculata, Lanistes nyassanus, and Marisa cornuarietis has opened the opportunity for a comprehensive analysis of HSP superfamily in the ampullariids. We identified the number of HSP from P. canaliculata (PcaHSPs) was greater than that from the other three species. A total of 42 PcaHSPs were distributed on 12 chromosomes and were classified into the families of HSP90, HSP70, HSP60, HSP40, HSP20, and HSP10. Each family formed a monophyletic clade on the phylogenetic tree with strong support values, except for the HSP90 and HSP70 families. The RNA-seq data shows that most the PcaHSPs were of tissue-specific expression levels. Moreover, we identified more HSP genes with stronger transcription levels in response to heat than cold stress. Our findings are informative for future studies on stress adaptation and developing effective management strategies focusing on HSPs in invasive apple snails.

Overexpression of SmLAC25 promotes lignin accumulation and decreases salvianolic acid content in Salvia miltiorrhiza.

Laccase (LAC) is a blue multicopper oxidase that contains four copper ions, which is involved in lignin polymerization and flavonoid biosynthesis in plants. Although dozens of LAC genes have been identified in Salvia miltiorrhiza Bunge (a model medicinal plant), most have not been functionally characterized. Here, we explored the expression patterns and the functionality of SmLAC25 in S. miltiorrhiza. SmLAC25 has a higher expression level in roots and responds to methyl jasmonate, auxin, abscisic acid, and gibberellin stimuli. The SmLAC25 protein is localized in the cytoplasm and chloroplasts. Recombinant SmLAC25 protein could oxidize coniferyl alcohol and sinapyl alcohol, two monomers of G-lignin and S-lignin. To investigate its function, we generated SmLAC25-overexpressed S. miltiorrhiza plantlets and hairy roots. The lignin content increased significantly in all SmLAC25-overexpressed plantlets and hairy roots, compared with the controls. However, the concentrations of rosmarinic acid and salvianolic acid B decreased significantly in all the SmLAC25-overexpressed lines. Further studies revealed that the transcription levels of some key enzyme genes in the lignin synthesis pathway (e.g., SmCCR and SmCOMT) were significantly improved in the SmLAC25-overexpressed lines, while the expression levels of multiple enzyme genes in the salvianolic acid biosynthesis pathway were inhibited. We speculated that the overexpression of SmLAC25 promoted the metabolic flux of lignin synthesis, which resulted in a decreased metabolic flux to the salvianolic acid biosynthesis pathway.

Non-Viral Delivery of Gene Therapy to the Tendon.

The tendon, as a compact connective tissue, is difficult to treat after an acute laceration or chronic degeneration. Gene-based therapy is a highly efficient strategy for diverse diseases which has been increasingly applied in tendons in recent years. As technology improves by leaps and bounds, a wide variety of non-viral vectors have been manufactured that attempt to have high biosecurity and transfection efficiency, considered to be a promising treatment modality. In this review, we examine the unwanted biological barriers, the categories of applicable genes, and the introduction and comparison of non-viral vectors. We focus on lipid-based nanoparticles and polymer-based nanoparticles, differentiating between them based on their combination with diverse chemical modifications and scaffolds.

Effect of pediatric- versus adult-type chemotherapy regimens on outcomes of allogeneic hematopoietic stem cell transplants for adult T-cell acute lymphoblastic leukemia in first complete remission.

The optimal chemotherapy regimen pre-transplantation for adult T-cell acute lymphoblastic leukemia (T-ALL) patients remains unknown. Here, we compared the transplant outcomes in 127 subjects receiving pediatric- (N = 57) or adult-type (N = 70) regimens pre-transplant. The corresponding 3-year cumulative incidences of relapse (CIR) was 7% (95% CI: 3-11%) and 29% (95% CI: 23-35%; P = 0.02), leukemia-free survivals (LFS) was 86% (95% CI: 81-91%) and 57% (95% CI: 51-63%; P = 0.003), overall survivals (OS) was 88% (95% CI: 84-92%) and 58% (95% CI: 52-64%; P = 0.002), the 1-year NRM was 4% (95% CI: 1-7%) and 9% (95% CI: 4-14%; P = 0.40). Multivariate analysis showed that pediatric-type regimen was associated with lower CIR (Hazard Ratio [HR] = 0.31 [95% CI: 0.09-1.00]; P = 0.05), better LFS (HR = 0.34 [95% CI: 0.15-0.78]; P = 0.01) and OS (HR = 0.30 [95% CI: 0.13-0.72]; P = 0.01). Our results suggested that adult T-ALL patients undergoing allo-HSCT might benefit from pediatric-type chemotherapy.

The influence of a nanoparticle gel loaded with siRNA-cyclooxygenase on flexor tendon healing: an in vivo animal study.

We investigated the influence of cyclooxygenase (COX)-1 and COX-2 siRNAs delivered through a nanoparticle-gel system on the strength of flexor tendon repairs. Sixteen flexor digitorum profundus (FDP) tendons of chicken toes were transected, repaired and wrapped with gels to evaluate gel adherence. We found that the gel adhered to the tendon surface firmly. Next, 56 tendons were used in a first set of in vivo experiments to compare the therapeutic effects of different doses of COX siRNAs. Another 15 tendons were added in a second set to further assess the effects of a dosage of 12 µg. After 4 weeks, the mean strength of the repaired tendons increased most notably in the toes treated with 12 µg COX siRNAs, and the number of samples with low strength (<35 N) was significantly smaller than in the group without molecular treatment. We conclude that COX-1 and COX-2 siRNAs delivered through a nanoparticle-gel system increased the healing strength of the repaired tendons.

A reverse transcription-cross-priming amplification method with lateral flow dipstick assay for the rapid detection of Bean pod mottle virus.

Bean pod mottle virus (BPMV) is a destructive virus that causes serious economic losses in many countries every year, highlighting the importance of its effective detection. In this study, we developed a fast reverse transcription-cross-priming amplification (RT-CPA) coupled with lateral flow dipstick (LFD) diagnostic method for BPMV detection. The RT-CPA-LFD assay that targets the coat protein gene of BPMV was highly specific against diagnosing four other common viruses transmitted by soybean seeds, i.e., Southern bean mosaic virus (SBMV), Tomato ringspot virus (ToRSV), Arabis mosaic virus (ArMV), and Tobacco ringspot virus (TRSV). The sensitivities of the real-time fluorescent RT-CPA and the RT-CPA-LFD assay were at least 50 pg/µl and 500 pg/µl, respectively. Despite a compromise in the limit of detection of the RT-CPA method compared with TaqMan-MGB real-time RT-PCR, our results demonstrated a notably better performance in the detection of field samples of BPMV-infested soybean seeds. With the advantages of efficiency and convenience by visual determination, the RT-CPA-LFD assay presents a potential application for the rapid and accurate detection of BPMV in routine tests.

Association Between SHMT1 rs1979277 Polymorphism and Risk of Acute Lymphoblastic Leukemia: A Systematic Review and Meta-analysis.

OBJECTIVES: The aim of this study was to explore the potential association the cytosolic serine hydroxy methyltransferase (SHMT1) rs1979277 polymorphism and the risk of acute lymphoblastic leukemia (ALL). MATERIALS AND METHODS: Comprehensive search of Web of Science, PubMed, Ovid, Cochrane Library, Embase, China National Knowledge Infrastructure (CNKI), and China Biomedical Literature Database electronic database, was performed to identify relevant studies published throughout April 30, 2019. The heterogeneity in the study was judged by the I2 and P-values, and then the random ratio or fixed effect was used to calculate the pooled odds ratios (OR) based on the presence or absence of heterogeneity. Sensitivity analysis is used to estimate the impact of individual studies on aggregate estimates. The publication bias of the study was tested using a funnel plot and an Egger regression. RESULTS: Nine studies with a total of 6492 participants (2971 patients; 3521 controls) were included in this meta-analysis. We found that SHMT1 rs1979277 polymorphism was not significantly associated with the risk of ALL in the dominant model: CC versus CT+TT (OR=0.84, 95% confidence interval [CI]: 0.46-1.54, P=0.57), recessive model: CC+CT versus TT (OR=0.81, 95% CI: 0.44-1.49, P=0.50) and allele model: C versus T (OR=0.84, 95% CI: 0.52-1.35, P=0.48). In subgroup analysis by ethnicity, no significant association were found in dominant, recessive and allele models in both Caucasian and Asian populations. CONCLUSION: Our study indicated that the SHMT1 rs1979277 polymorphism was not associated with the risk of susceptibility to ALL.

Morphological changes of macrophages and their potential contribution to tendon healing.

Poor healing ability and adhesion formation greatly hinder the recovery of injured tendon function. Previously, our local sustained gene delivery system by using cyclooxygenases (COX-1 and COX-2)-engineered miRNA plasmid/nanoparticles loaded hydrogel significantly inhibited adhesion formation and promoted tendon healing. The present study aims to study morphological changes of the macrophages in the healing tendons after above treatment with the hydrogel. Firstly, we assessed the therapeutic effect of localized delivery of the hydrogel on cyclooxygenases in the injured rat Achilles tendon model. We found ultimate strengths of the healing tendons were significantly increased at week 2 and 3. We then studied the distribution of macrophages before and after tendon injury, and found macrophages were rapidly recruited into injured sites of tendons. After being isolated and cultured, macrophages were transfected with 6-Carboxyfluorescein (FAM) labeled siRNA/nanoparticles and presented a high transfection efficiency (>70%). We further compared the change of iNOS/CD206 in macrophages between negative control siRNA/nanoparticle group and COX siRNA/nanoparticle group. The major finding is that the morphology of the macrophages changed from type I macrophages to type II macrophages after transfection of COX siRNA/nanoparticles in vitro. Subsequently, rat Achilles tendon cells were cultured with supernatant collected from macrophages transfected with negative control siRNA/nanoparticles and COX siRNA/nanoparticles, and the proliferation of tendon cells was significantly increased in COX siRNA/nanoparticle supernatant group. Because type II macrophages are responsible for tissue repair, the changes in macrophage polarization from M1 to M2 may be one of the important events in promoting the tendon healing.

Basic Research on Tendon Repair: Strategies, Evaluation, and Development.

Tendon is a fibro-elastic structure that links muscle and bone. Tendon injury can be divided into two types, chronic and acute. Each type of injury or degeneration can cause substantial pain and the loss of tendon function. The natural healing process of tendon injury is complex. According to the anatomical position of tendon tissue, the clinical results are different. The wound healing process includes three overlapping stages: wound healing, proliferation and tissue remodeling. Besides, the healing tendon also faces a high re-tear rate. Faced with the above difficulties, management of tendon injuries remains a clinical problem and needs to be solved urgently. In recent years, there are many new directions and advances in tendon healing. This review introduces tendon injury and sums up the development of tendon healing in recent years, including gene therapy, stem cell therapy, Platelet-rich plasma (PRP) therapy, growth factor and drug therapy and tissue engineering. Although most of these therapies have not yet developed to mature clinical application stage, with the repeated verification by researchers and continuous optimization of curative effect, that day will not be too far away.

Sustained-Release Hydrogel-Based Rhynchophylline Delivery System Improved Injured Tendon Repair.

During the injured flexor tendon healing process, tendon tissue is easy to form extremely dense adhesion with the surrounding tissue, which causes the serious influence of hand function recovery. Uncaria is widely used in clinic and its main composition, Rhynchophylline (Rhy), has been reported on its good therapeutic effect, which could effectively inhibit the intra-abdominal adhesion formation. However, the therapeutic effect of Rhy on tendon healing and adhesion formation is still unclear. Due to the short half-life of Rhy, hyaluronic acid (HA) sustained-release system for Rhy delivery was constructed and it could also avoid drug from the undesired loss during the transit. After Rhy delivery system was applied around the injured tendons, adhesion formation, gliding function and healing strength of tendons were evaluated. Our results showed that the gliding excursion and healing strength of repaired tendons were both significantly increased, as well as the adhesion was inhibited. From in vivo experiments, Rhy could be able to increase the expression of Col Ⅰ/Col Ⅲ and helped fibroblasts to ordered organization for tendon tissues. But for adhesion tissues, Rhy promoted the apoptosis and accelerated the degradation of extracellular matrix. In vitro study showed Rhy could help tenocytes stimulated with TGF-ß1 to recover to normal cell functions involving cell proliferation and apoptosis level. Through high-throughput sequencing, we found that Rhy was involved in the regulation of Extracellular Matrix (ECM) signaling pathway. We draw a conclusion that Rhy enhanced the tendon healing and prevented adhesion formation through inhibiting the phosphorylation of Smad2. In a word, this sustained release system of Rhy may be a promising strategy for the treatment of injured tendons.