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A broad-spectrum “turn-on” fluorescent sensor for organic amines has been established with a bis-catechol-decorated naphthalene scaffold. It is first synthesized through green chemistry processing with lower solvent consumption.

The type III secretion system (T3SS) is a key factor in the pathogenesis of Pseudomonas syringae pv. actinidiae biovar 3 (Psa3), the causal agent of a global kiwifruit bacterial canker pandemic. To monitor the T3SS expression levels in Psa3, we constructed a luciferase reporter plasmid-expressing HrpAPsa3-NLuc fusion protein. The expression of HrpA-NLuc was induced in hrp-inducing conditions whereas the level of luciferase activity correlated with the expression of hrp/hrc genes in Psa3 confirmed the reliability of the reporter construct. Based on the readout of the NLuc reporter construct, three small molecule compounds 4-methoxy-cinnamic acid, sulforaphane, and ferulic acid were determined as T3SS inhibitors in Psa3, whereas sodium acetate was determined to be a T3SS inducer. Moreover, the aqueous extract of fruit inhibited the accumulation of HrpA-NLuc in Psa3 in medium and in planta. Additionally, the T3SS inhibitors suppress Psa3 virulence, whereas the T3SS inducer promotes Psa3 virulence on kiwifruit. Thus, our findings may provide clues to why the fruit is not infected by Psa3, and the Psa3 T3SS inhibitors have potential as alternatives to current nonspecific antimicrobials for disease management.

Bacterial canker of kiwifruit is a devastating disease caused by Pseudomonas syringae pv. actinidiae (Psa). The type III secretion system (T3SS), which translocates effectors into plant cells to subvert plant immunity and promote extracellular bacterial growth, is required for Psa virulence. Despite that the “HrpR/S-HrpL” cascade that sophisticatedly regulates the expression of T3SS and effectors has been well documented, the transcriptional regulators of hrpR/S remain to be determined. In this study, the OmpR-like transcription factor, previously identified by DNA pull-down assay, was found to be involved in the regulation of hrpR/S genes, and its regulatory mechanisms and other functions in Psa were explored through techniques including gene knockout and overexpression, ChIP-seq, and RNA-seq. The OmpR-like transcription factor had binding sites in the promoter region of the hrpR/S, and the transcriptional level of the hrpR/S increased after the deletion of OmpR-like and decreased upon its overexpression in an OmpR-like deletion background. Additionally, OmpR-like overexpression reduced the strain’s capacity to form biofilms and lipopolysaccharides, led to its slow growth in King’s B medium, and reduced its swimming ability, although there was no significant effect on its pathogenicity against kiwifruit hosts. Our results indicated that OmpR-like directly and negatively regulates the transcription of hrpR/S and may be involved in the regulation of multiple biological processes in Psa. Our results provide a basis for further understanding the transcriptional regulation mechanism of hrpR/S in Psa.

The primary objective was to evaluate the efficacy and safety of Er:YAG laser treatment for meibomian gland dysfunction (MGD) in a prospective study. A total of 128 eyes from 64 patients with MGD were enrolled to receive either three Er:YAG laser treatments with meibomian gland expression (MGX) or MGX-alone treatment sessions at 3-week intervals. The Standard Patient Evaluation of Eye Dryness (SPEED) validated questionnaire; fluorescein breakup time of the tear film (FBUT); corneal fluorescein staining (CFS); lid margin abnormalities; meibomian gland morphology (meiboscore); lower tear meniscus height (TMH); and assessment of 15 meibomian glands in the lower eyelids, including total meibomian gland secretion quality (TMGS), the number of glands secreting any liquid (GSAL), and the number of glands yielding optimal clear liquid secretion (GYCL), were assessed at day (D)0, D21, D42, and D63 for the Er:YAG-MGX group and D0 and D63 for the MGX group. At D63, significant decreases in SPEED scores and lid margin abnormalities as well as significant increases in FBUT, TMGS, and GSAL were observed in both groups (all p

The quorum-sensing (QS) signaling-dependent extracellular virulence factors of Pseudomonas aeruginosa can cause infections such as P. aeruginosa keratitis. P. aeruginosa communicates by secreting and sensing small chemical molecules called autoinducers in QS system. The key QS signal molecule, N-3-oxododecanoyl-homoserine lactone (3OC12HSL), can affect the behavior of host cells and initiate immune response. In this report we investigated the influence of 3OC12HSL on human corneal epithelial cells (HCECs) and the mechanisms of 3OC12HSL on activated toll-like receptor 2 (TLR2)-dependent interleukin-8 (IL-8) secretion in HCECs. Cells were cultured under different concentrations of 3OC12HSL. Cell viability was assessed using Crystal violet staining and the cell counting kit-8 assay. We demonstrated the administration of 3OC12HSL decreased HCEC viability and survival in a concentration- and time-dependent manner. At high concentrations, 3OC12HSL rapidly promoted a time-dependent increase in the expressions of TLR2 and TLR4. It was found that the nuclear translocation and expression of nuclear factor-κB (NF-κB) were also increased in response to 3OC12HSL treatment. The significantly elevated expressions of TLR2, TLR4, and NF-κB, encouraged us to further test their mechanisms that cause inflammatory response. Among the inflammatory factors examined (IL-6, IL-8, IL-10, and TNF-α), we found that IL-8 was significantly increased after treatment with 3OC12HSL and its expression was inhibited when TLR2 was specifically blocked or silenced. These results indicated that the QS signaling molecule 3OC12HSL could be recognized by the host innate immune system in HCECs. This recognition then triggered an immune inflammatory response involving the activation of TLR2 and an increase in expression of IL-8. This crosstalk between 3OC12HSL and host immunity in HCECs contributes to the development and progression of P. aeruginosa keratitis.

The dynamic reversible Diels-Alder (DA) reactions play essential roles in both academic and applied fields. Currently, in situ visualization and direct monitoring of the formation and cleavage of covalent bonds in DA reactions are hampered by finite compatibility and expensive precise instruments, especially limited in solid reactions. We herein report a fluorescence system capable of in situ visualization by naked eyes and monitoring DA/retro-DA reactions. With the fluorescence quenching effect, the synthesized TPEMI could work as an innovative self-indicator for both DA termination and retro-DA occurrence. The fluorescence increases during DA reactions, and the mechanism is investigated to establish qualitative and quantitative relations. Besides rapid screening of reaction conditions and monitoring of DA exchange processes, the TPEMI fluorescence system can visualize heterogeneous and solid-state reactions with the AIE character. The TPEMI platform is expected to offer novel insights into reversible DA processes and dynamic covalent chemistry.

Novel functional AIEgen based on three compact bound aryl skeletons is designed and synthesized. This tri-aryl type luminogen (TA-Catechol) embedded with catechol moiety responds rapidly to series of boronic acids. Real-time visual and quantitative dual-mode detection method is established for the first time with modest precision and low detection limit (8.0 μM). Detailed mechanistic discussion identifies tetra-coordinated boronic species as the key intermediate within sensing procedure. Wide range of organic boronic acids compatible with this strategy is displayed which is promising in high throughput screening technology. Furthermore, solid-state sensing capability of TA-Catechol is also demonstrated.

A new aggregation-induced emission (AIE) luminescence core, 1-hydroquinol-1,2,2-triphenylethene (HQTPE), has been designed and synthesized for the first time. This AIE core is amazingly simple but is fundamentally important to chemistry because of its intrinsic redox and pH activities. The incorporation of hydroquinone (HQ) moiety into a common AIE core tetraphenylethene (TPE) yields HQTPE with unique fluorescent properties over most other AIEgens so far reported. There are tremendous differences of photochemcical properties between HQTPE, 1-benzoquinol-1,2,2-triphenylethene (QTPE, the oxidized counterpart) and its anions. Interestingly, as the solution concentration is increased, AIEgen HQTPE shows stronger fluorescence but QTPE exhibits rapid quenching of fluorescence in a nonlinear fashion, which are in agreement with theoretical studies. The fluorescence of HQTPE is also highly dependent of pH value of media. We have further explored HQTPE as an ultrasensitive redox probe and efficient deoxidizer, which could lead to many potential applications in health care, food security, environmental monitoring, optic and electronic devices.

The primary objective was to evaluate the efficacy and safety of Er:YAG laser treatment for meibomian gland dysfunction (MGD) in a prospective study.A total of 128 eyes from 64 patients with MGD were enrolled to receive either three Er:YAG laser treatments with meibomian gland expression (MGX) or MGX-alone treatment sessions at 3-week intervals. The Standard Patient Evaluation of Eye Dryness (SPEED) validated questionnaire; fluorescein breakup time of the tear film (FBUT); corneal fluorescein staining (CFS); lid margin abnormalities; meibomian gland morphology (meiboscore); lower tear meniscus height (TMH); and assessment of 15 meibomian glands in the lower eyelids, including total meibomian gland secretion quality (TMGS), the number of glands secreting any liquid (GSAL), and the number of glands yielding optimal clear liquid secretion (GYCL), were assessed at day (D)0, D21, D42, and D63 for the Er:YAG-MGX group and D0 and D63 for the MGX group.At D63, significant decreases in SPEED scores and lid margin abnormalities as well as significant increases in FBUT, TMGS, and GSAL were observed in both groups (all p 0.05). The Er:YAG-MGX group showed a significantly better improvement in SPEED scores, TMGS, and GYCL than the MGX group (all p 0.05).Although preliminary, the study results of Er:YAG laser treatment for dry eye syndrome caused by MGD are promising. Er:YAG laser treatment may be a new direction for managing MGD.The study was registered at www.chictr.org.cn : ChiCTR1900026004.

Pseudomonas aeruginosa (P. aeruginosa) keratitis is a sight-threatening and rapidly progressive corneal disease. Neutrophils and neutrophil extracellular traps (NETs) are widely thought to play a vital role in hosts’ immune defenses against bacteria, such as P. aeruginosa. The present study aimed to investigate the dynamics of the formation and the role of NETs in P. aeruginosa keratitis. First, scratched corneas of mice models were treated with 1 × 108 colony-forming units (CFU)/ml of P. aeruginosa suspension or normal saline (NS). Second, after 48 h postinfection, the infected corneas were treated with TobraDex, Tobrex, 0.1% dexamethasone, or NS four times a day, respectively. Clinical examination, hematoxylin and eosin (H&E) staining, immunofluorescence staining, scanning electron microscopy, and bacterial burden testing were performed on the corneas. Tobrex reduced neutrophil infiltration and corneal P. aeruginosa burden. Dexamethasone reduced NETs, bacterial burden, and severe neutrophil infiltration. TobraDex produced a greater reduction in the amount of neutrophils, NETs, and bacterial burden and the results of Tobrex-treated group were between them. These findings corresponded with the clinical findings that TobraDex- and Tobrex-treated mice exhibited slight corneal damage, while dexamethasone-treated mice exhibited very severe corneal damage. Cumulatively, our data suggest that NETs may play a dual role of infection control and corneal damage in P. aeruginosa keratitis. Furthermore, combination treatment targeting NET formation and bacteria may serve as a way of improving the clinical outcomes of bacterial keratitis.

AIM: To observe the efficacy of different artificial eye drops on corneal epithelium healing in rabbit. METHODS: Thirty-five rabbits with 6 mm diameter central corneal epithelium removed were randomly assigned to six groups: 0.9% normal saline (NS) group, 0.1% hyaluronate (HA) group, 0.3% HA group, Tears Naturale Free® (TNF) group, 0.4% polyethylene glycol (PEG) group, 0.5% carboxymethyl cellulose (CMC) group and blank control group. Treatments were administered topically four times daily. Corneal epithelium healing was evaluated by the percentage reduction in wound area at 24, 36, 48, 60, and 72h after removal of the corneal epithelium. Cornea re-epithelialization was also assessed by histological analysis and electron microscopy. RESULTS: All corneal wounds completely re-epithelialized in less than 72h. The average re-epithelialization time was 47.61±4.25h in the 0.3% HA group and 49.72±1.05h in the 0.9% NS group, followed by 0.1% HA, TNF, 0.4% PEG, 0.5% CMC, and lastly by the control group. Compared to the control group, there were significant differences among 0.3% HA, 0.9% NS, PEG, and TNF (P

The current research of mechanochromic molecules focused on different molecular skeletons and the types of functional groups, where the design ideas were limited. We have synthesized a group of cyano-modified TPE derivatives (TPECN) with different substitution sites, showing typical aggregation induced emission (AIE) effect. We found that meta-substituted mCN revealed the inertness of mechanochromism, whether being ball milled or rapidly evaporated. Isomers with ortho- or para-substitution showed an emission wavelength shift over 40 nm. Experimental data indicated unusual high-strength lattice stability for mCN. By single-crystal analysis and theoretical calculations, we clarified from the molecular skeleton distortion, noncovalent intermolecular interactions, and calculated interaction energy that the meta-substitution led to a stable lattice structure, making mCN insensitive to external stimuli. Thus, we successfully explained the substituted site was an important and independent factor that influenced the mechanochromic property. Meanwhile, we also explored the application of the TPECNs series for erasable printing and coding.

Catalytic oxidative cross-dehydrogenative coupling between unactivated C(sp2)–H and C(sp3)–H bonds is achieved by the cobalt-catalyzed o-alkylation reaction of aromatic carboxamides containing (pyridin-2-yl)isopropyl amine (PIP–NH2) as a N,N-bidentate directing group. Many different C(sp3)–H bonds in alkanes, toluene derivatives and even in the α-position of ethers and thioethers can be used as coupling partners. This method has a broad substrate scope and the tolerance of various functional groups.

Purpose: To evaluate whether glucocorticoids affect the prognosis of fungal keratitis by inhibiting the formation of neutrophil extracellular traps (NETs).Methods: A mouse model of Candida albicans (C.albicans) keratitis was established. Animals were randomly assigned to treatment with 0.1% dexamethasone (DXM) eye drops and normal saline (3 times each day for 3 days). The effects of DXM on fungal keratitis were assessed using clinical scores, immunofluorescence staining, histopathological examination, scanning electron microscopy (SEM), and pathogen burden assay. All the analyses were performed using SPSS software version 17.0 (Chicago, IL).Results: NETs formation was noteworthy in the cornea lesions of fungal keratitis. The clinical score of the DXM-treated group was significantly higher than that of the control group (P < .05). During the measured period, corneas from DXM-treated group contained more C.albicans than those from the control group by histology and pathogen burden assay. Compared with the control group, the DXM treatment group had a higher depth of infiltration of C.albicans. Histological and immunofluorescence staining showed that there were fewer neutrophils in the cornea focus of DXM-treated group (P < .05）, and the number of NETs formed in scrapings from control group was higher than that in the DXM treatment group on day 3 (P < .05, Z = -3.56)) and day 5 (P < .05, Z = -3.69). In a similar amount of cell scraping, the NETs of neutrophils formation from the DXM-treated group were also less than that from the control group.Conclusion: Our results indicated that NETs were involved in the immune response in C.albicans keratitis. Glucocorticoids may exacerbate fungal keratitis not only by increasing fungal aggressivity and reducing the infiltration of neutrophils but also by inhibiting the formation of NETs.

The first cobalt-catalyzed direct methylation of a C(sp(2) )-H bond using dicumyl peroxide (DCP) as both the methylating reagent and hydrogen acceptor has been established. The reaction proceeded without the use of any additives, and was proven to be applicable to various amides bearing a 2-pyridinylisopropyl (PIP) directing group, providing an efficient access to o-methyl aryl amides with high functional-group tolerance. Preliminary mechanistic studies suggest a radical process would be involved in the catalytic process.

Objectives To investigate the effects of neutrophil extracellular traps (NETs) on angiogenesis in vitro and in vivo and the regulatory role of mammalian target of rapamycin (mTOR) activity in it. Methods The regulatory role of mTOR in NETs formation was explored. In vitro, human neutrophils were pretreated with rapamycin. NETs formation was measured using immunofluorescence staining of NETs markers, SYTOX Green and PicoGreen after NaOH stimulation. In vivo, mice were treated with rapamycin, and NETs formation in cornea was measured using immunofluorescence staining 7 days after alkali burn. Then, the effects of NETs on angiogenesis were investigated. In vitro, human neutrophils were treated with DNase I or rapamycin. NETs were isolated after NaOH stimulation and the isolated NETs were co-culture with human umbilical vein endothelial cells (HUVECs). HUVECs migration, proliferation, and inflammatory activation were measured. In vivo, mice were injected subconjunctivally with supernatant containing NETs. Corneal neovascularization was visualized by immunofluorescence staining. Results NETs structures can be observed in NaOH-stimulated neutrophils and alkali-burned mouse cornea compared with normal group. Treated with rapamycin enhanced NETs formation in response to NaOH management compared with DMSO control in vitro and in vivo. NETs increased the migration, proliferation and inflammatory activation of HUVECs, and subconjunctival injection of NETs promoted inflammatory and angiogenic response in corneal alkali burn model. Conclusions NETs formation can be triggered by NaOH stimulation. mTOR activity has a negative regulatory effect on NETs formation. NETs promoted angiogenic responses and inflammatory activation of HUVECs and increased corneal neovascularization and inflammatory response.

Glioma is the most common and malignant form of primary brain tumour, and is characterised by high proliferation and extensive invasion and neurological destruction. Demethylzeylasteral (T-96), which is extracted from Tripterygium wilfordii, is considered to have immunosuppressive, anti-inflammatory and anti-angiogenic effects. Here, the anti-tumour effect of T-96 on glioma was evaluated. Our results demonstrated that T-96 significantly inhibited glioma cell growth and induced cell cycle arrest in G1 phase but did not induce apoptosis. Cell invasion and migration were dramatically suppressed after treatment with T-96. Almost all genes related to cell cycle and DNA replication were downregulated after treatment with T-96. Our results showed that miR-30e-5p was noticeably upregulated after T-96 treatment, and MYBL2, which is involved in cell cycle progression and is a target gene of miR-30e-5p, was significantly reduced in synchrony. Overexpression of MYBL2 partially rescued the T-96-induced inhibition of cell growth and proliferation. Moreover, a miR-30e-5p antagomir significantly reduced the upregulation of miR-30e-5p expression induced by T-96, leading to recovery of MYBL2 expression, and partially rescued the T-96-induced inhibition of cell growth and proliferation. More important, T-96 effectively upregulated miR-30e-5p expression and downregulated MYBL2 expression, thus inhibiting LN-229 cell tumour growth in a mouse model. These results indicated that T-96 might inhibit glioma cell growth by regulating the miR-30e-5p/MYBL2 axis. Our study demonstrated that T-96 might act as a promising agent for malignant glioma therapy.

Catalytic oxidative cross-dehydrogenative coupling between unactivated C(sp

Neutrophils release neutrophil extracellular traps (NETs) in a pathogen-killing process called NETosis. Excessive NETs formation, however, is implicated in disease pathogenesis. Therefore, to understand how NETosis is regulated, we examined the effect of dexamethasone (DXM), an anti-inflammatory drug, on this process and the role of toll-like receptors (TLRs). We stimulated human neutrophils with phorbol 12-myristate 13-acetate (PMA) or Staphylococcus aureus (S. aureus) and quantified NETs formation. We also examined the effect of DXM on the bactericidal effect of NETs and the role of reactive oxygen species (ROS) and nuclear factor (NF)-κB in DXM-regulated NETosis. DXM significantly inhibited S. aureus-induced NETosis and extracellular bacterial killing. ROS production and NF-κB activation were not involved in DXM-regulated NETosis. TLR2 and TLR4, but not TLR5 or TLR6, modified S. aureus-induced NETs formation. Neither DXM nor TLRs were involved in PMA-induced NETosis. Furthermore, TLR2 and TLR4 agonists rescued DXM-inhibited NETosis, and neither TLR2 nor TLR4 antagonists could further inhibit NETosis reduction induced by DXM, indicating that DXM may inhibit NETosis by regulating TLR2 and TLR4. In conclusion, the mechanisms of S. aureus- and PMA-induced NETosis are different. DXM decreases NETs formation independently of oxidant production and NF-κB phosphorylation and possibly via a TLR-dependent mechanism.

Allogeneic hematopoietic stem cell transplantation (HSCT) is a well-established therapeutic option for a range of inherited and acquired hematological disorders. However, graft-versus-host disease (GVHD) remains the leading cause of non-relapse mortality in allogeneic HSCT recipients. Ocular involvement occurs in up to 80% of chronic GVHD patients. In our cases, the diagnosis of vitamin A deficiency was suspected for GVHD patients. Serum vitamin A measurements were conducted to confirm clinical suspicions. Our study revealed significant decrease in serum levels of vitamin A in chronic liver GVHD patients. Although there have been many studies evaluating ocular manifestations in patients with GVHD, the present study is, to our knowledge, the first to study the relationship between vitamin A and ocular manifestations of GVHD in humans. Our data suggest that vitamin A deficiency affects the severity of ocular GVHD in adults.

The first cobalt-catalyzed direct methylation of a C(sp(2) )-H bond using dicumyl peroxide (DCP) as both the methylating reagent and hydrogen acceptor has been established. The reaction proceeded without the use of any additives, and was proven to be applicable to various amides bearing a 2-pyridinylisopropyl (PIP) directing group, providing an efficient access to o-methyl aryl amides with high functional-group tolerance. Preliminary mechanistic studies suggest a radical process would be involved in the catalytic process.

Neuroblastoma is the one of the most common extracranial childhood malignancies, accounting for ∼15% of tumor-associated deaths in children. It is generally considered that neuroblastoma originates from neural crest cells in the paravertebral sympathetic ganglia and the adrenal medulla. However, the mechanism by which neuroblastoma arises during sympathetic neurogenesis and the cellular mechanism that drives neuroblastoma development remains unclear. The present study investigated the cell components during neuroblastoma development in the tyrosine hydroxylase-v-myc avian myelocytomatosis viral oncogene neuroblastoma derived homolog (TH-MYCN) mouse model, a transgenic mouse model of human neuroblastoma. The present study demonstrates that paired-like homeobox 2b (Phox2B)+ neuronal progenitors are the major cellular population in hyperplastic lesions and primary tumors. In addition, Phox2B+ neuronal progenitors in hyperplastic lesions or primary tumors were observed to be in an actively proliferative and undifferentiated state. The current study also demonstrated that high expression levels of Phox2B promotes neuroblastoma cell proliferation and xenograft tumor growth. These findings indicate that the proliferation of undifferentiated Phox2B+ neuronal progenitors is a cellular mechanism that promotes neuroblastoma development and indicates that Phox2B is a critical regulator in neuroblastoma pathogenesis.