Photoinduced Palladium-Catalyzed Radical Heck-Type Coupling of Cyclobutanone Oxime Esters with Vinyl Arenes.

A palladium-catalyzed radical Heck-type coupling reaction of cyclobutanone oxime esters with olefins under visible-light irradiation has been developed. The cyanoalkyl/Pd(I) hybrid species generated by selected ring-opening C-C bond cleavage of imino/Pd(I) species reacted smoothly with vinyl arenes, delivering the cyanoalkylation olefins under mild conditions. This elegant strategy has a broad scope and functional group tolerance. Subsequently, late-stage functionalization of bioactive molecules and synthetic transformations of the product further confirm the practicality.

IL-6/STAT3 axis is hijacked by GCRV to facilitate viral replication via suppressing type â IFN signaling.

Grass carp reovirus (GCRV) infections and hemorrhagic disease (GCHD) outbreaks are typically seasonally periodic and temperature-dependent, yet the molecular mechanism remains unclear. Herein, we depicted that temperature-dependent IL-6/STAT3 axis was exploited by GCRV to facilitate viral replication via suppressing type Ⅰ IFN signaling. Combined multi-omics analysis and qPCR identified IL-6, STAT3, and IRF3 as potential effector molecules mediating GCRV infection. Deploying GCRV challenge at 18 °C and 28 °C as models of resistant and permissive infections and switched to the corresponding temperatures as temperature stress models, we illustrated that IL-6 and STAT3 expression, genome level of GCRV, and phosphorylation of STAT3 were temperature dependent and regulated by temperature stress. Further research revealed that activating IL-6/STAT3 axis enhanced GCRV replication and suppressed the expression of IFNs, whereas blocking the axis impaired viral replication. Mechanistically, grass carp STAT3 inhibited IRF3 nuclear translocation via interacting with it, thus down-regulating IFNs expression, restraining transcriptional activation of the IFN promoter, and facilitating GCRV replication. Overall, our work sheds light on an immune evasion mechanism whereby GCRV facilitates viral replication by hijacking IL-6/STAT3 axis to down-regulate IFNs expression, thus providing a valuable reference for targeted prevention and therapy of GCRV.

Identification of PGRP2 and its three splice variants in grass carp Ctenopharyngodon idella.

In this study, peptidoglycan recognition protein 2 (PGRP2) gene was cloned in grass carp Ctenopharyngodon idella, with the open reading frame (ORF) of PGRP2 being 1452 bp, encoding a protein of 483 amino acids. Three splice variants, PGRP2a, PGRP2b, and PGRP2c, were found also in grass carp with the absence of entire exon two and partial exon two of the PGRP2, and were predicted to have 124, 371 and 311 amino acids. But, they all have PGRP domain and signal peptide, except PGRP2a. The PGRP2 and its variants were expressed in all organs/tissues examined, and stimulated following PGN injection. It is further detected that the expression of gcPGRP2 and its variants was up-regulated after the single transfection of each of gcPGRP2 and its variant expression plasmids in CO cells. It is considered that the cloning of PGRP2 in grass carp provides a compositional completeness of PGRP members in this fish with the inclusion of previously reported PGRP5 and PGRP6.

[Unique characteristics of "the second brain" - The enteric nervous system].

Enteric nervous system (ENS) is composed of intestinal submucosal and myenteric plexuses. ENS may independently regulate intestinal digestive and absorptive function, and it is also known as "the second brain" or gut brain. ENS has significant specificity relative to central nervous system (CNS) in properties and functional activities of neurons and neural circuits. ENS is connected with CNS through the feedback pathway (brain-gut-axis) of sympathetic and parasympathetic nerves and peripheral primary sensory afferent nerves to form the bidirectional brain-gut-axis, which may affect emotion, appetite and behavioral states of individuals. Gastrointestinal functional disorder (GIFD) induced by ENS dysfunction may not only cause abnormal gastrointestinal function but also has been implicated in cognitive and mood disorders, such as irritable bowel syndrome (IBS). GIFD would influence deeply the quality of life in patients. Nevertheless, in the worldwide, ENS has so far received much less attention as compared with CNS. The depth of research and scale of investment in ENS studies have been much lower than those in CNS studies. The situation in China is even more evident. From ENS research history, an outstanding problem is to ignore largely the unique properties of ENS and apply mechanically the hypotheses formed in CNS studies to ENS researches. In this review, the structure and function of ENS are briefly introduced, and the importance of extraordinary characteristics of ENS is illustrated by the problems encountered in our studies.

[Clinical application value of liquid dressing after circumcision].

OBJECTIVE: To explore and analyze the effect of liquid dressing in relieving pain and preventing incision adhesion after circumcision and its clinical application value. METHODS: Ninety male patients underwent circumcision in Hangzhou Third People's Hospital from September to November 2019, with the incision covered with liquid dressing + vaseline gauze (group A, n = 30), liquid dressing alone (group B, n = 30) or vaseline gauze only (group C, n = 30). At 2, 4 and 6 days after surgery, we compared the Visual Analogue Scale (VAS) pain intensity at dressing change, incision bleeding after dressing removal and incidence of postoperative complications among the three groups of patients. RESULTS: At 2, 4 and 6 days after surgery, the VAS pain score and incidence of incision bleeding were significantly lower in groups A and B than in C (P < 0.05). At 2 days, both the VAS pain score and incidence of incision bleeding were markedly decreased in group A as compared with those in group B (P < 0.05). At 4 and 6 days, the VAS pain score remained lower in group A than in B (P < 0.05), but the incidence rate of incision bleeding showed no significant difference between the two groups (P > 0.05). No statistically significant differences were observed in the incidence of postoperative complications among the three groups (P > 0.05). CONCLUSIONS: Liquid dressing can reduce pain intensity at dressing change, prevent incision adhesion and consequent dressing change-induced tearing and bleeding, and therefore promote incision healing after circumcision. Its combination with vaseline gauze can achieve an even better effect.

[5-aminolevulinic acid photodynamic therapy for condyloma acuminata with high-risk HPV infection and local cellular immunoactivity of the patient].

OBJECTIVE: To observe the clinical effects of the 5-aminolevulinic acid photodynamic therapy (ALA-PDT) on condyloma acuminata with high-risk human papillomavirus (HPV) infection and cellular immunoactivity in the local tissue of the patient. METHODS: From January 2015 to January 2017, we treated 47 cases of condyloma acuminata with high-risk HPV infection in our hospital by simple excision of the wart (the control group, n = 21) or 1－5 times of ALA-PDT plus wart excision (the observation group, n = 26) and observed the changes in the number of warts and recurrence at 6 months after surgery. We excised all the warts in the control group and those >5 mm before ALA-PDT and >2 mm at 48 hours after 1－5 times of ALA-PDT in the observation group, followed by examination of the counts of CD4+ and CD8+ T cells, CD4+ / CD8+ ratio, and number of CD68+ macrophages in the local tissue by immunohistochemistry. RESULTS: In the control group, the warts were completely removed in all the 21 cases but recurred in 9 (42.9%) at 6 months after surgery. In the observation group, 5 times of ALA-PDT achieved complete removal of the warts in 16 (61.5%) of the 26 patients, partial removal in 7 (26.9%), and inefficient removal in 3 (11.5%), with a total effective removal rate of 88.5% (23/26), a significantly lower 6-month recurrence rate (11.5% ï¼»3/26ï¼½) than in the control (P < 0.05), but no such severe complications as festering, scarring and pigmentation. Compared with the control group and the baseline, the observation group showed remarkable increases after 1, 3 and 5 times of ALA-PDT in the counts of CD4+ T lymphocytes (31.21 ± 6.23 and 30.27 ± 5.63 vs 56.88 ± 4.72, 54.67 ± 2.84 and 42.62 ± 2.31, P < 0.05) and CD8+ T cells (25.31 ± 3.51 and 27.35 ± 3.78 vs 48.87 ± 2.47, 45.41 ± 3.17 and 37.58 ± 3.32, P < 0.01) and the CD4+ / CD8+ ratio (1.21 ± 0.52 and 1.09 ± 0.37 vs 1.68 ± 0.52, 1.63 ± 0.45 and 1.42 ± 0.13, P < 0.05 or P < 0.01), but exhibited no significant change in the count of CD68+ macrophages in the local tissue (23.31 ± 1.54 and 20.25 ± 1.28 vs 22.31 ± 2.73, 23.17 ± 2.41 and 21.35 ± 3.72, P > 0.05). CONCLUSIONS: ALA-PDT, with its advantages of high efficiency, little invasion and high safety, is effective for the treatment of condyloma acuminata with high-risk HPV infection and it can also improve cellular immunoactivity in the local tissue and reduce recurrence.

An Experimental Study on the Optimal Timing for the Repair of Incomplete Facial Paralysis by Hypoglossal-facial 'Side'-to-side Neurorrhaphy in Rats.

OBJECTIVE: To investigate the optimal timing for the repair of persistent incomplete facial paralysis by hypoglossal-facial 'side'-to-side neurorrhaphy in rats. METHODS: A total of 30 adult rats with crushed and bulldog-clamped facial nerve injury were randomly divided into 5 groups (n = 6 each) that were subjected to injury without nerve repair or with immediate repair, 2-week-delayed repair, 4-week-delayed repair, or 8-week-delayed repair. Three months later, the effects of repair in each rat were evaluated by facial symmetry assessment, electrophysiological examination, retrograde labeling, and axon regeneration measurement. RESULTS: At 3 months after injury, the alpha angle significantly increased in the group of rats with 4-week-delayed repair compared with the other four groups. Upon stimulation of the facial nerve or Pre degenerated nerve, the muscle action potentials MAPs were recorded in the whisker pad muscle, and the MAP amplitude and area under the curve in the 4-week-delayed repair group were significantly augmented at 3 months post-injury. Similarly, the number of retrograde-labeled motor neurons in the facial and hypoglossal nuclei was quantified to be significantly greater in the 4-week-delayed repair group than in the other groups, and a large number of regenerated axons was also observed. CONCLUSION: The results of this study demonstrated that hemiHN-FN neurorrhaphy performed 4 weeks after facial nerve injury was most effective in terms of the functional recovery of axonal regeneration and activation of facial muscles.

Squaramide-Catalyzed Asymmetric Reactions.

Bifunctional squaramides have emerged as powerful hydrogen-bonding catalysts for promoting a wide array of useful asymmetric reactions, which provides convenient methods for the construction of complex molecular structures and chiral biologically active compounds. This review highlights the recent advances of our research group in the chiral squaramide-catalyzed asymmetric reactions, including Michael addition, Mannich reaction, aza-Henry reaction, Strecker reaction as well as cascade or sequential reactions.

Prognostic value of EUS combined with MSCT in predicting the recurrence and metastasis of patients with gastric cancer.

OBJECTIVE: This study aims to explore the prognostic value of endoscopic ultrasonography combined with multi-slice spiral computed tomography in predicting the recurrence and metastasis of gastric cancer, as well as investigate the correlation of fragile histidine triad protein expression with the tumor-node-metastasis stage of gastric cancer patients. METHODS: A total of 81 gastric cancer patients were selected in our study. All patients were examined by endoscopic ultrasonography and multi-slice spiral computed tomography before operation, and gastric cancer tissues and adjacent normal tissues were obtained after operation. Immunohistochemistry was performed to detect fragile histidine triad expression. All patients were followed up for 3 years after operation. Univariate and multivariate analysis of risk factors were conducted for the prognosis of gastric cancer patients. RESULTS: Endoscopic ultrasonography combined with multi-slice spiral computed tomography could increase the accuracy of preoperative tumor-node-metastasis stage of gastric cancer patients. In gastric cancer tissues, fragile histidine triad expression was mostly weakly positive with a positive rate of 60.5%. In gastric cancer adjacent normal tissues, the positive fragile histidine triad expression was mostly moderate with a positive rate of 79.0%. The fragile histidine triad expression was negatively correlated with tumor-node-metastasis stage of gastric cancer patients. The fragile histidine triad expression decreased along with the increase of T-stage, N-stage and M-stage of gastric cancer patients. Univariate and multivariate analysis showed that T-stage and N-stage were risk factors for the recurrence/metastasis and 3-year mortality of gastric cancer patients, while fragile histidine triad expression was a protective factor. CONCLUSION: Our study demonstrated that endoscopic ultrasonography combined with multi-slice spiral computed tomography may be more accurate in assessing the preoperative tumor-node-metastasis stage of gastric cancer patients.

The application of MutMap in forward genetic studies based on whole-genome sequencing.

Classical forward genetic analysis relies on construction of complicated progeny populations and development of many molecular markers for linkage analysis in genetic mapping, which is both time- and cost-consuming. The recently developed MutMap is a new forward genetic approach based on high-throughput next-generation sequencing technologies. It is more efficient and affordable than traditional methods. Moreover, new extended methods based on MutMap have been developed: MutMap+, which is based on self-crossing; MutMap-Gap, which is used to recognize the causative variations occurring in genome gap regions; QTL-seq, a method similar to MutMap for mapping quantitative trait loci. These methods are free from constructing complicated mapping population, genetic hybridization and linkage information. They have greatly accelerated the identification of genetic elements associated with interested phenotypic variation. Here, we review the basic principles of MutMap, and discuss their future applications in next generation sequencing-based forward genetic mapping and crop improvement.

NOD2 in zebrafish functions in antibacterial and also antiviral responses via NF-κB, and also MDA5, RIG-I and MAVS.

NOD2/RIPK2 signalling plays essential role in the modulation of innate and adaptive immunity in mammals. In this study, NOD2 was functionally characterized in zebrafish (Danio rerio), and its interaction with a receptor-interaction protein, RIPK2, and RLRs such as MDA5 and RIG-I, as well as the adaptor, MAVS was revealed in fish innate immunity. The expression of NOD2 and RIPK2 in ZF4 cells has been constitutive and can be induced by the infection of Edwardsiella tarda and SVCV. The NOD2 can sense MDP in PGN from Gram-negative and -positive bacteria. It is further revealed that the NOD2 and RIPK2 can activate NF-κB and IFN promoters, inducing significantly antiviral defense against SVCV infection. As observed in the reduced bacterial burden in RIPK2 overexpressed cells, RIPK2 also has a role in inhibiting the bacterial replication. The overexpression of NOD2 in zebrafish embryos resulted in the increase of immune gene expression, especially those encoding PRRs and cytokines involved in antiviral response such as MDA5, RIG-I, and type I IFNs, etc. Luciferase reporter assays and co-immunoprecipitation assays demonstrated that zebrafish NOD2 is associated with MDA5 and RIG-I in signalling pathway. In addition, it is further demonstrated that RIPK2 and MAVS in combination with NOD2 have an enhanced role in NOD2-mediated NF-κB and type I IFN activation. It is concluded that teleost fish NOD2 can not only sense MDP for activating innate immunity as reported in mammals, but can also interact with other PRRs to form a network in antiviral innate response.

Construction of Spirocyclopropane-Linked Heterocycles Containing Both Pyrazolones and Oxindoles through Michael/Alkylation Cascade Reactions.

An effective diastereoselective Michael/alkylation cascade reaction of arylidenepyrazolones with 3-chlorooxindoles catalyzed by DIPEA was developed. A variety of highly functionalized spiro-pyrazolone-cyclopropane-oxindoles were obtained in excellent yields (up to 99%) with good to excellent diastereoselectivities (up to >25:1 dr). Moreover, the squaramide-catalyzed asymmetric reactions of arylidenepyrazolones with 3-chlorooxindoles afforded the corresponding chiral spirocyclic heterocycles in excellent yields (up to 99%) with moderate diastereoselectivities (up to 87:13 dr) and moderate to high enantioselectivities (up to 74% ee).

Enantioselective cascade double Michael addition of 3-nitro-2H-chromenes and acyclic enones: efficient synthesis of functionalized tricyclic chroman derivatives.

An efficient protocol for the asymmetric construction of enantiomerically enriched tetrahydro-6H-benzo[c]chromenes and their derivatives has been developed. The corresponding products were obtained by the cascade double Michael addition of 3-nitro-2H-chromenes and their derivatives with α,ß-unsaturated ketones catalyzed by a combination of a quinine-derived primary amine and benzoic acid. Through this methodology, the desired products could be obtained in moderate to good yields (up to 90%), with excellent diastereoselectivities (up to >25 : 1 dr) and moderate to excellent enantioselectivities (up to 95% ee).

Enantioselective synthesis of chiral heterocycles containing both chroman and pyrazolone derivatives catalysed by a chiral squaramide.

An efficient chiral squaramide-catalysed enantioselective Michael addition of pyrazolin-5-ones to 3-nitro-2H-chromenes for the synthesis of chiral heterocyclic systems containing both chroman and pyrazolone derivatives has been developed. This reaction afforded the desired products in high to excellent yields (up to 98%) with high enantioselectivities (up to 96%) and excellent diastereoselectivities (up to 99 : 1) under very low catalyst loading (0.2 mol%). This catalytic asymmetric reaction provides an efficient route toward the synthesis of chiral heterocyclic systems containing both chroman and pyrazolone derivatives, which possess potential pharmaceutical activities.

Melanoma differentiation-associated gene 5 in zebrafish provoking higher interferon-promoter activity through signalling enhancing of its shorter splicing variant.

Melanoma differentiation-associated gene 5 (MDA5) is one of the three members in the retinoic acid-inducible gene I-like receptor (RLR) family, which are cytoplasmic pathogen recognition receptors recognizing intracellular viruses. In the present study, MDA5 and its spliced shorter forms, named as MDA5a and MDA5b, were identified in zebrafish. MDA5a and MDA5b can be up-regulated in cell lines following the infection of a negative ssRNA virus, the spring viraemia of carp virus (SVCV), and an intracellular Gram-negative bacterial pathogen Edwardsiella tarda, implying that the RLR may also be able to sense elements released from bacteria. The over-expression of MDA5a and MDA5b in fish cells resulted in significant induction of type I interferon promoter activity and enabled the protection of transfected cells against SVCV infection. Furthermore, the shorter spliced form, MDA5b when co-transfected with MDA5a or mitochondrial antiviral signalling protein (MAVS), induced a significantly higher level of interferon promoter activity, indicating that MDA5b may function as an enhancer in the interaction between MDA5 and MAVS.

Glucocorticoid receptor agonist dexamethasone attenuates renal ischemia/reperfusion injury by up-regulating eNOS/iNOS.

The aim of this study was to determine the effect of dexamethasone (DEX) on renal ischemia/reperfusion injury (IRI). C57BL/6 mice were randomly divided into Sham group, IRI group and DEX group. The mice in IRI and DEX groups subjected to renal ischemia for 60 min, were treated with saline or DEX (4 mg/kg, i.p.) 60 min prior to I/R. After 24 h of reperfusion, the renal function, renal pathological changes, activation of extracellular signal-regulated kinase (ERK) and glucocorticoid receptor (GR), and the levels of iNOS and eNOS were detected. The results showed DEX significantly decreased the damage to renal function and pathological changes after renal IRI. Pre-treatment with DEX reduced ERK activation and down-regulated the level of iNOS, whereas up-regulated the level of eNOS after renal IRI. DEX could further promote the activation of GR. These findings indicated GR activation confers preconditioning-like protection against acute IRI partially by up-regulating the ratio of eNOS/iNOS.

Icariin accelerates bone regeneration by inducing osteogenesis-angiogenesis coupling in rats with type 1 diabetes mellitus.

BACKGROUND: Icariin (ICA), a natural flavonoid compound monomer, has multiple pharmacological activities. However, its effect on bone defect in the context of type 1 diabetes mellitus (T1DM) has not yet been examined. AIM: To explore the role and potential mechanism of ICA on bone defect in the context of T1DM. METHODS: The effects of ICA on osteogenesis and angiogenesis were evaluated by alkaline phosphatase staining, alizarin red S staining, quantitative real-time polymerase chain reaction, Western blot, and immunofluorescence. Angiogenesis-related assays were conducted to investigate the relationship between osteogenesis and angiogenesis. A bone defect model was established in T1DM rats. The model rats were then treated with ICA or placebo and micron-scale computed tomography, histomorphometry, histology, and sequential fluorescent labeling were used to evaluate the effect of ICA on bone formation in the defect area. RESULTS: ICA promoted bone marrow mesenchymal stem cell (BMSC) proliferation and osteogenic differentiation. The ICA treated-BMSCs showed higher expression levels of osteogenesis-related markers (alkaline phosphatase and osteocalcin) and angiogenesis-related markers (vascular endothelial growth factor A and platelet endothelial cell adhesion molecule 1) compared to the untreated group. ICA was also found to induce osteogenesis-angiogenesis coupling of BMSCs. In the bone defect model T1DM rats, ICA facilitated bone formation and CD31hiEMCNhi type H-positive capillary formation. Lastly, ICA effectively accelerated the rate of bone formation in the defect area. CONCLUSION: ICA was able to accelerate bone regeneration in a T1DM rat model by inducing osteogenesis-angiogenesis coupling of BMSCs.

The role of small RNAs in resistant melon cultivar against Phelipanche aegyptiaca parasitization.

Bidirectional trans-kingdom RNA silencing, a pivotal factor in plant-pathogen interactions, remains less explored in plant host-parasite dynamics. Here, using small RNA sequencing in melon root systems, we investigated microRNA (miRNA) expression variation in resistant and susceptible cultivars pre-and post-infection by the parasitic plant, broomrape. This approach revealed 979 known miRNAs and 110 novel miRNAs across 110 families. When comparing susceptible (F0) and resistant (R0) melon lines with broomrape infection (F25 and R25), 39 significantly differentially expressed miRNAs were observed in F25 vs. F0, 35 in R25 vs. R0, and 5 in R25 vs. F25. Notably, two miRNAs consistently exhibited differential expression across all comparisons, targeting genes linked to plant disease resistance. This suggests their pivotal role in melon's defense against broomrape. The target genes of these miRNAs were confirmed via degradome sequencing and validated by qRT-PCR, ensuring reliable sequencing outcomes. GO and KEGG analyses shed light on the molecular functions and pathways of these differential miRNAs. Furthermore, our study unveiled four trans-kingdom miRNAs, forming a foundation for exploring melon's resistance to broomrape.

Palladium-catalyzed alkynylation of allylic gem-difluorides.

Herein, a palladium-catalyzed regioselective alkynylation, esterification, and amination of allylic gem-difluorides via C-F bond activation/transmetallation/ß-C elimination or nucleophilic attack has been achieved. This innovative protocol showcases an extensive substrate range and operates efficiently under mild reaction conditions, resulting in high product yields and Z-selectivity. Particularly noteworthy is its exceptional tolerance towards a wide array of functional groups. This developed methodology provides effective and convenient routes to access a diverse array of essential fluorinated enynes, esters and amines.

Features of MR signals of retroplacental basal decidual space and its diagnostic significance.

BACKGROUND: With more pregnant women undergoing cesarean section, the number of women with scarring in the uterus undergoing uterine magnetic resonance (MR) examination in the second and third trimesters following a subsequent pregnancy, has increased. OBJECTIVE: To investigate features of MR signals in retroplacental basal decidual space. METHODS: The MR imaging data of patients with clinically and pathologically confirmed placenta implantation and complete placental abruption were retrospectively analyzed. RESULTS: Patients with high-intensity signals in T2-weighted images (T2WI) of the retroplacental basal decidual space did not suffer placenta implantation after delivery, while high-intensity signals in T2WI of the retroplacental basal decidual space was not observed in patients with different degrees of placenta implantation. CONCLUSION: As the retroplacental basal decidual space is the barrier between the placenta and myometrium, high-intensity signals in T2WI can improve the confidence of MR exclusion diagnostics of placenta implantation, and can be used as exclusion criteria for MR diagnosis of placenta implantation.