The G143S mutation in cytochrome b confers high resistance to pyraclostrobin in Fusarium pseudograminearum.

BACKGROUND: Wheat crown rot (WCR), primarily caused by Fusarium pseudograminearum has become more and more prevalent in winter wheat areas in China. However, limited fungicides have been registered for the control of WCR in China so far. Pyraclostrobin is a representative quinone outside inhibitor (QoI) with excellent activity against Fusarium spp. There is currently limited research on the resistance risk and resistance mechanism of F. pseudograminearum to pyraclostrobin. RESULTS: Here, we determined the activity of pyraclostrobin against F. pseudograminearum. The EC50 values ranged from 0.022 to 0.172 µg mL-1 with an average EC50 value of 0.071 ± 0.030 µg mL-1. Four highly pyraclostrobin-resistant mutants were obtained from two sensitive strains by ultraviolet (UV) mutagenesis in the laboratory. The mutants showed decreased mycelial growth rate and virulence as compared with the corresponding wild-type strains, indicating that pyraclostrobin resistance suffered a fitness penalty in F. pseudograminearum. It was found that the high resistance of four mutants was caused by the G143S mutation in Cytb. Molecular docking analysis also further confirms that the G143S mutation in Cytb decreased the binding affinity between pyraclostrobin and Cytb. CONCLUSION: The resistance risk of F. pseudograminearum to pyraclostrobin could be low to medium. Although a mutation at the G143S position of Cytb could potentially occur, this mutation decreases the fitness of the mutant, which may reduce its survival in the environment. Therefore, the negative consequences of a possible mutation are lower. This makes pyraclostrobin a good candidate for controlling crown rot in wheat. © 2024 Society of Chemical Industry.

UPLC-Q-Exactive/MS based analysis explore the correlation between components variations and anti-influenza virus effect of four quantified extracts of Chaihu Guizhi decoction.

ETHNOPHARMACOLOGICAL RELEVANCE: Chaihu Guizhi decoction (CGD) is a classic Traditional Chinese Medicine (TCM) prescription for the treatment of influenza and fever, composes of Bupleuri Radix (Chaihu), Cinnamomi Ramulus (Guizhi), Scutellariae Radix (Huangqin), Codonopsis Radix (Dangshen), Glycyrrhizae Radix Et Rhizoma Praeparata Cum Melle (Zhigancao), Pinelliae Rhizoma Praeparatum (Fabanxia), Zingiberis Rhizoma Recens (Shengjiang), Paeoniae Radix Alba (Baishao) and Jujubae Fructus (Dazao) in the ratio of 12:4.5:4.5:4.5:3:6:4.5:4.5:4. The efficacy of TCM, if there are differences, depends on the different extraction methods and extracted components. AIM OF THE STUDY: This study was to evaluate the anti-influenza virus effect of CGD extracts with different extraction methods, analyze the components and explore their correlation. MATERIALS AND METHODS: CGD were prepared with four extraction methods respectively, the traditional decoction (TD), two steps alcohol-water extraction (AWE), alcohol reflux extraction (AE) and water reflux extraction (WE). Based on the influenza mouse model, the efficacy of anti-influenza virus in vivo of the four CGD extracts were evaluated with the therapeutic index of body weight, rectal temperature, lung index, thymus index and lung viral load of mice. The chemical components in four CGD extracts, and compounds absorbed in rats blood with prototypes or metabolites were identified by UPLC-Q-Exactive/MS. The partial least squares (PLS) method was used to explore the correlation between the components variation in CGD extracts and the comprehensive efficacy index. The potential effective components were further accessed by molecular docking. RESULTS: Comparing with the other three extracts, AWE has the best anti-influenza effect. It could ameliorate the symptoms caused by influenza virus infection in mice, increase body weight and rectal temperature, reduce the lung index and virus load in lung tissue. 129, 144, 140 and 129 components were identified from TD, AWE, AE, and WE respectively. The identified components were mainly including flavonoids, terpenoids, organic acids, phenylpropanoids, amino acids, nucleosides, phenols, alkaloids, etc. 43 prototypes and 49 metabolites of CGD were detected in rat plasma after oral administration. Seven components, cinnamaldehyde, wogonoside, baicalin, baicalein, gallic acid, oroxylinA-7-O-glucuronide and coumarin, showed significant correlation with anti-influenza effects, all of which had good binding activity with NA, IL-6, STAT3, AKT1, EGFR and TNF. CONCLUSION: Two steps alcohol-water extraction was optimal for CGD preparation. Cinnamaldehyde, wogonoside, oroxylinA-7-O-glucuronide, coumarin, gallic acid, baicalein and baicalin play a certain essential role in anti-influenza effects and may be taken as a potential maker compounds for quality evaluation of CGD.

The lung-gut crosstalk in respiratory and inflammatory bowel disease.

Both lung and gut belong to the common mucosal immune system (CMIS), with huge surface areas exposed to the external environment. They are the main defense organs against the invasion of pathogens and play a key role in innate and adaptive immunity. Recently, more and more evidence showed that stimulation of one organ can affect the other, as exemplified by intestinal complications during respiratory disease and vice versa, which is called lung-gut crosstalk. Intestinal microbiota plays an important role in respiratory and intestinal diseases. It is known that intestinal microbial imbalance is related to inflammatory bowel disease (IBD), this imbalance could impact the integrity of the intestinal epithelial barrier and leads to the persistence of inflammation, however, gut microbial disturbances have also been observed in respiratory diseases such as asthma, allergy, chronic obstructive pulmonary disease (COPD), and respiratory infection. It is not fully clarified how these disorders happened. In this review, we summarized the latest examples and possible mechanisms of lung-gut crosstalk in respiratory disease and IBD and discussed the strategy of shaping intestinal flora to treat respiratory diseases.

Licochalcone A plays dual antiviral roles by inhibiting RSV and protecting against host damage.

Respiratory syncytial virus (RSV) causes lower respiratory tract diseases and bronchiolitis in children and elderly individuals. There are no effective drugs currently available to treat RSV infection. In this study, we report that Licochalcone A (LCA) can inhibit RSV replication and mitigate RSV-induced cell damage in vitro, and that LCA exerts a protective effect by reducing the viral titer and inflammation in the lungs of infected mice in vivo. We suggest that the mechanism of action occurs through pathways of antioxidant stress and inflammation. Further mechanistic results demonstrate that LCA can induce nuclear factor erythroid 2-related factor 2 (Nrf2) translocation into the nucleus, activate heme oxygenase 1 (HO-1), and inhibit reactive oxygen species-induced oxidative stress. LCA also works to reverse the decrease in I-kappa-B-alpha (IкBα) levels caused by RSV, which in turn inhibits inflammation through the associated nuclear factor kappa B and tumor necrosis factor-α signaling pathways. The combined action of the two cross-talking pathways protects hosts from RSV-induced damage. To conclude, our study is the first of its kind to establish evidence of LCA as a viable treatment for RSV infection.

2D layered BP/InSe and BP/Janus In2SeX (X = S or Te) type-II van der Waals heterostructures for photovoltaics: insight from first-principles calculations.

Constructing van der Waals (vdW) heterostructures provides an effective and feasible method for 2D materials to improve their properties and extend their possible applications. Using first-principles calculations, we explored the atomic and electronic structures of Janus In2SeX (X = S or Te) and revealed the existence of a vertical internal intrinsic electric field in these Janus monolayers. Then, we stacked the pristine InSe and Janus In2SeX (X = S or Te) with black phosphorus (BP) vertically to construct vdW heterostructures with a mismatch of less than 5% and systematically investigated their interface atomic structures and possible applications in photovoltaics. The calculation results reveal that the constructed vdW heterostructures can be synthesized experimentally, and the type-II band alignment can be found in all vdW heterostructures, which is independent of the internal electric field of Janus monolayers, the built-in dipole at the interface between two domains, and the number of layers. In addition, the vdW heterostructures show stronger light absorption compared to monolayer individuals, and the type-II band alignment can help the photo-excited carriers to separate and achieve an excellent photovoltaic power conversion efficiency of up to about 21% in these heterostructures. These extraordinary results suggest that these vdW heterostructures have great potential for more efficient solar photovoltaic applications.

Qingjin Huatan decoction protects mice against influenza a virus pneumonia via the chemokine signaling pathways.

ETHNOPHARMACOLOGICAL RELEVANCE: Qingjin Huatan Decoction (QJHTT) consists of 11 herbal medicines: Scutellaria baicalensis Georgi, Gardenia jasminoides J.Ellis, Platycodon grandiflorus (Jacq.) A.DC., Ophiopogon japonicus (Thunb.) Ker Gawl., Morus alba L., Fritillaria thunbergii Miq., Anemarrhena asphodeloides Bunge, Trichosanthes kirilowii Maxim., Citrus reticulata Blanco, Poria cocos (Schw.) Wolf, and Glycyrrhiza uralensis Fisch. As a traditional compound Chinese medicinal formula, QJHTT has been used for more than 400 years in China. Historically, it was used to treat respiratory diseases and had shown beneficial clinical results for diseases related to lung inflammation. AIM OF THE STUDY: To investigate the therapeutic effect of QJHTT on influenza A virus (IAV) pneumonia in mice and explore its possible mechanism of action. MATERIALS AND METHODS: The components in QJHTT were analyzed by UPLC-Q-TOF-MS and some antiviral active components reported in the literature were determined and quantified by HPLC. The protective effects of QJHTT were investigated using lethal and sublethal doses (2 LD50 or 0.8 LD50 viral suspension, separately) of H1N1-infected mice. Mortality and lung lesions in H1N1-infected mice were used to evaluate the efficacy of QJHTT. The potential mechanism of QJHTT in the treatment of viral pneumonia was determined at the gene level by RNA sequencing and validated by qRT-PCR. Following this, the changes in protein levels of JAK2/STAT3 were analyzed since it is a key downstream target of the chemokine signaling pathways. Preliminary elucidation of the mechanism of QJHTT to protect mice against IAV pneumonia through this pathway was conducted. RESULTS: In this study, 12 antiviral active constituents including baicalin, geniposide, and mangiferin were identified from QJHTT. In vivo treatment of QJHTT reduced the virus titers of lung tissue significantly and improved the survival rate, lung index, and pulmonary histopathological changes; additionally, a reduction in the serum levels of TNF-α, IL-1ß, IL-6, and IFN-γ inflammatory factors in H1N1-infected mice was observed. RNA-seq analysis and qRT-PCR showed that QJHTT primarily reversed the activities CCL2, CCL7, CCR1, and other chemokines and their reception-related genes, suggesting that QJHTT may produce disease-resistant pneumonia by inhibiting the downstream JAK2/STAT3 pathway. Western blot analysis confirmed that QJHTT effectively reduced the protein levels of JAK2, STAT3, and related phosphorylated products in the lung tissue of H1N1-infected mice. CONCLUSIONS: Our results indicated that QJHTT alleviated IAV pneumonia in mice by regulating related chemokines and their receptor-related genes in lung tissue, thereby inhibiting JAK2/STAT3 pathway. This could pave way for the design of novel therapeutic strategies to treat viral pneumonia.

The G143A/S substitution of mitochondrially encoded cytochrome b (Cytb) in Magnaporthe oryzae confers resistance to quinone outside inhibitors.

BACKGROUND: Rice blast, caused by Magnaporthe oryzae, is a destructive disease threatening the production of staple foods worldwide. Quinone outside inhibitors (QoIs) are a group of chemicals exhibiting excellent activity against a majority of plant pathogens, with the disadvantage that pathogens can easily develop resistance to QoIs. RESULTS: Here, we investigated the activity of picoxystrobin against M. oryzae, which showed a great inhibitory effect on 100 strains of M. oryzae with half-maximal effective concentrations (EC50 ) ranging from 0.0251 to 0.1337 µg ml-1 . The EC50 values showed a continuous unimodal distribution that was identical to the normal distribution, suggesting the potency of our study to represent baseline sensitivity. In addition, nine resistant mutants were obtained by exposing M. oryzae to a high dosage of picoxystrobin in the laboratory; all of them showed cross-resistance to the other five QoI fungicides. Although some mutants showed a decreased resistance factor after ten successive cultures on fungicide-free medium, the resistance to picoxystrobin was still inheritable. Amino acid substitution of G143S was detected in eight of nine picoxystrobin-resistant mutants, and G143A was detected in only one of nine mutants. A fitness penalty was found in the mutants carrying G143S rather than G143A. CONCLUSION: Our findings suggested that M. oryzae had a mid to high risk of resistance to picoxystrobin. Considering this, we should be vigilant to the resistance risk and apply picoxystrobin sensibly in the field. © 2022 Society of Chemical Industry.

Efficient biosynthesis of exopolysaccharide in Candida glabrata by a fed-batch culture.

Polysaccharides are important natural biomacromolecules. In particular, microbial exopolysaccharides have received much attention. They are produced by a variety of microorganisms, and they are widely used in the food, pharmaceutical, and chemical industries. The Candida glabrata mutant 4-C10, which has the capacity to produce exopolysaccharide, was previously obtained by random mutagenesis. In this study we aimed to further enhance exopolysaccharide production by systemic fermentation optimization. By single factor optimization and orthogonal design optimization in shaking flasks, an optimal fermentation medium composition was obtained. By optimizing agitation speed, aeration rate, and fed-batch fermentation mode, 118.6 g L-1 of exopolysaccharide was obtained by a constant rate feeding fermentation mode, with a glucose yield of 0.62 g g-1 and a productivity of 1.24 g L-1 h-1. Scaling up the established fermentation mode to a 15-L fermenter led to an exopolysaccharide yield of 113.8 g L-1, with a glucose yield of 0.60 g g-1 and a productivity of 1.29 g L-1 h-1.

Monolayer Sc2CF2 as a Potential Selective and Sensitive NO2 Sensor: Insight from First-Principles Calculations.

Two-dimensional materials with excellent surface-volume ratios and massive reaction sites recently have been receiving attention for gas sensing. With first-principles calculations, we explored the performance of monolayer Sc2CF2 as a gas sensor. We investigated how molecule adsorption affects its electronic structure and optical properties. It is found that a large charge transfer quantity happens between Sc2CF2 and NO2, which results from the fact that the lowest unoccupied molecular orbital (LUMO) of NO2 is below the valence band maximum (VBM) of Sc2CF2. Moreover, the MD simulation shows that NO2 can adsorb on the Sc2CF2 surface stably at room temperature. We explored the effect of biaxial strain on the adsorption energy and charge transfer quantity of each system, and the results show that the biaxial strain can enhance both the adsorption energy and charge transfer quantity of the NO2 system and thus can improve the sensitivity of Sc2CF2 in detecting the NO2 molecule. Furthermore, we investigated the adsorption behavior and charge transfer of polar polyatomic molecules at the Sc2CF2 surface with h-BN as a substrate, and the results demonstrate that the h-BN substrate can hardly modify the main results. Our result predicts that Sc2CF2 can be a promising selective and sensitive sensor to detect the NO2 molecule, and could also give a theoretical guide for other terminated MXenes used for gas sensors or detectors.

miR-5191 acts as a tumor suppressor in salivary adenoid cystic carcinoma by targeting Notch-2.

OBJECTIVE: This study sought to investigate the effect of miR-5191 on proliferation, invasion and metastasis in salivary adenoid cystic carcinoma (SACC). MATERIALS AND METHODS: The differential expression level of miR-5191 between 5 primary tumor and adjacent non-neoplastic samples, and in two SACC cell lines was detected by quantitative real-time PCR. Cell proliferation, invasion, and migration were performed, followed by luciferase reporter assay and western analysis. The effect of miR-5191 on cell proliferation and apoptosis was evaluated by cell growth and apoptosis assay. The function of miR-5191 in SACC tumorigenesis and metastasis in vivo was investigated by nude mice experiment. The associations between miR-5191/Notch-2 expression and clinicopathological features were analyzed. RESULTS: miR-5191 was downregulated in primary tumor tissues and SACC-LM cells. By targeting Notch-2, miR-5191 expression level affected the migration, invasion, and proliferation of SACC cells. Overexpression of miR-5191 inhibited the expression levels of Notch-2, followed by the decreased expression of c-Myc, Bcl-2, Hes-1, Hey-1, and Cyclin D1. In vivo, miR-5191 overexpression suppressed the SACC tumorigenesis and pulmonary metastasis in mice. In SACC patients, higher expression of miR-5191 was related to better prognoses and lower possibility of metastasis. CONCLUSIONS: miR-5191 acts as a tumor suppressor in SACC by targeting Notch-2.

Dynamic formation and transcriptional regulation mediated by phytohormones during chalkiness formation in rice.

BACKGROUND: Rice (Oryza sativa L.) Chalkiness, the opaque part in the kernel endosperm formed by loosely piled starch and protein bodies. Chalkiness is a complex quantitative trait regulated by multiple genes and various environmental factors. Phytohormones play important roles in the regulation of chalkiness formation but the underlying molecular mechanism is still unclear at present. RESULTS: In this research, Xiangzaoxian24 (X24, pure line of indica rice with high-chalkiness) and its origin parents Xiangzaoxian11 (X11, female parent, pure line of indica rice with high-chalkiness) and Xiangzaoxian7 (X7, male parent, pure line of indica rice with low-chalkiness) were used as materials. The phenotype, physiological and biochemical traits combined with transcriptome analysis were conducted to illustrate the dynamic process and transcriptional regulation of rice chalkiness formation. Impressively, phytohormonal contents and multiple phytohormonal signals were significantly different in chalky caryopsis, suggesting the involvement of phytohormones, particularly ABA and auxin, in the regulation of rice chalkiness formation, through the interaction of multiple transcription factors and their downstream regulators. CONCLUSION: These results indicated that chalkiness formation is a dynamic process associated with multiple genes, forming a complex regulatory network in which phytohormones play important roles. These results provided informative clues for illustrating the regulatory mechanisms of chalkiness formation in rice.

Foaming of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with Supercritical Carbon Dioxide: Foaming Performance and Crystallization Behavior.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) samples were successfully foamed using supercritical carbon dioxide as a physical foaming agent. PHBV sheets were first saturated at 175 °C followed by a foaming process at different temperatures (145 to 165 °C) and different CO2 pressures (10 to 29 MPa). It was found that microcellular structures with average cell sizes ranging from 6 to 22 µm and cell densities ranging from 108 to 1.2 × 109 cells/cm3 could be controllably prepared by selecting suitable foaming conditions. To investigate crystallization behavior during the foaming process and explore the corresponding foaming mechanism, differential scanning calorimetry, wide angle X-ray diffraction, and small-angle X-ray scattering characterizations were carried out. Stretching behavior during the cell growth stage may increase the crystal nucleation rate, and the generated crystal nucleus accelerates the crystallization rate as well as thickens PHBV crystal lamellae.

PCNA-associated factor KIAA0101 transcriptionally induced by ELK1 controls cell proliferation and apoptosis in nasopharyngeal carcinoma: an integrated bioinformatics and experimental study.

KIAA0101, previously identified as PCNA-associated factor, is overexpressed among almost majority of human cancers and has emerged as an important regulator of cancer progression; however, its function in human nasopharyngeal carcinoma (NPC) remain unknown. Integrated bioinformatics approaches were employed to determine the KIAA0101 expressions in the NPC samples. Lentiviral vectors carrying KIAA0101 shRNA were constructed and stable transfected cells were validated by qRT-PCR and western blot. Cellular functions were then evaluated by MTT, colony formation, Brdu staining, and flow cytometry. Mechanistic studies were systematically investigated by UCSC Genome Browser, GEO, UALCAN, QIAGEN, PROMO and JASPAR, ChIP, and the cBioPortal, et al. The results showed that KIAA0101 ranked top overexpressed gene lists in GSE6631 dataset. KIAA0101 was highly expressed in NPC tissues and cell lines. Furthermore, knockdown of KIAA0101 significantly inhibited cell proliferation and DNA replication, promoted apoptosis and cell cycle arrest in vitro. Meanwhile, the mechanistic study revealed that MAP kinase phosphorylation-dependent activation of ELK1 may enhance neighbor gene expressions of KIAA0101 and TRIP4 by binding both promotor regions in the NPC cells. Taken together, our findings indicate that overexpression of KIAA0101 activated by MAP kinase phosphorylation-dependent activation of ELK1 may play an important role in NPC progression.

The Copy Number Variation of OsMTD1 Regulates Rice Plant Architecture.

Copy number variation (CNV) may have phenotypic effects by altering the expression level of the gene(s) or regulatory element(s) contained. It is believed that CNVs play pivotal roles in controlling plant architecture and other traits in plant. However, the effects of CNV contributing to special traits remain largely unknown. Here we report a CNV involved in rice architecture by modulating tiller number and leaf angle. In the genome of Oryza sativa ssp. japonica cv. Nipponbare, we found a locus Loc_Os08g34249 is derived from a 13,002-bp tandem duplication in the nearby region of OsMTD1, a gene regulating tillering in rice. Further survey of 230 rice cultivars showed that the duplication occurred in only 13 japonica rice cultivars. Phenotypic investigation indicated that this CNV region may contribute to tiller number. Moreover, we revealed that OsMTD1 not only influences rice tiller number and leaf angle, but also represses pri-miR156f transcription in the CNV region. Intriguingly, this CNV performs function through both the dosage and position effects on OsMTD1 and pri-miR156f. Thus, our work identified a CNV and revealed a molecular regulatory basis for its effects on plant architecture, implying this CNV may possess importance and application potential in molecular breeding in rice.

The application of 3D-printed titanium mesh in maxillary tumor patients undergoing total maxillectomy.

OBJECTIVE: To evaluate the clinical outcomes of reconstruction of maxillary class III defect using 3D-printed titanium mesh. METHODS: Twelve patients with maxillary class III defect from April 2015 to December 2016 were retrospectively studied. A 3D individualized maxillary stereo model based on mirror images of the unaffected maxilla was obtained to fabricate an anatomically adapted titanium mesh using computer-assisted design and manufacture. The individual titanium mesh was inserted into the maxillary class III defect after total maxillectomy. The incidence of postoperative complications was evaluated. The postoperative orbital volume and protrusion degree of eye were measured. RESULTS: All patients were satisfied with their postoperative facial symmetry, without developing diplopia or endophthalmos. The postoperative orbital volumes were 26.41 ± 0.52 mL on the affected side and 26.55 ± 0.45 mL on the unaffected side. The postoperative protrusion degrees of affected and unaffected eyes were 16.21 ± 0.48 and 16.82 ± 0.79 mm, respectively. Titanium mesh exposure was observed in 2 patients and mild limitation of mouth opening was observed in 4 patients who underwent postoperative radiotherapy. CONCLUSION: Reconstruction of maxillary class III defect with 3D-printed titanium mesh can achieve successful clinical outcomes, which recovered orbital volume and protrusion degree of eye. Twelve patients with maxillary class III defect were satisfied with their postoperative facial symmetry, without developing diplopia or endophthalmos. We investigated that reconstruction of maxillary class III defect with 3D-printed titanium mesh can achieve successful clinical outcomes.

Application of Three-Dimensional Printing Technology in the Orbital Blowout Fracture Reconstruction.

The aim of this study was to investigate the clinical outcomes of orbital blowout fracture repair by using the three-dimensional (3D) printing-assisted fabrication of individual titanium mesh. Clinical and radiologic data were analyzed for 12 patients with orbital floor and/or medial wall fractures. Lower eyelid incision was used to expose the fractures. Preoperative computed tomographic data were input into an imaging software to rebuild a 3D orbit and mirror the unaffected side into the affected side to replace the demolished orbit. A resin model of the reshaped orbit was generated and used to develop an individual titanium mesh for repairing the fractured orbital. The surgical results were assessed by value of enophthalmos and a comparison of preoperative and postoperative orbital volume difference. All patients had a successful treatment outcome without any complications. Clinical significant enophthalmos were not observed after treatment, and diplopia were solved within 2 weeks postoperative. No extraocular muscle limitation was observed. Postoperative computed tomography scans demonstrated appropriate positioning of titanium mesh and there was no implant displacement. The postoperative orbital volume and enophthalmos difference between the 2 eyes decreased significantly than preoperative (P < 0.001). Three-dimensional printing-assisted fabrication of individual titanium mesh is appropriate for use in orbital blowout fracture.

MicroRNA-27b inhibits cell proliferation in oral squamous cell carcinoma by targeting FZD7 and Wnt signaling pathway.

This study intended to investigate the role of microRNA-27b (miR-27b) in proliferation of oral squamous cell carcinoma (OSCC) cells and to explore the potential molecular mechanism. Cell proliferation was detected by MTT assay. The expression levels of miR-27b, Frizzled7 (FZD7), cyclin D1 and c-myc were detected by quantitative real time polymerase chain reaction (qRT-PCR). The protein expression level of FZD7 was detected by western blot analysis. The relationship between miR-27b and FZD7, and the activity of Wnt signaling pathway were determined using luciferase reporter assay. The miR-27b expression in OSCC cell lines was significantly decreased compared with control. Overexpression of miR-27b remarkably inhibited OSCC cell proliferation. Additionally, miR-27b could target and inhibit FZD7 expression and decrease the activity of Wnt signaling pathway.miR-27b could inhibit OSCC cell proliferation through inhibiting FZD7 and FZD7-mediated Wnt signaling pathway.

Mucoadhesive chitosan hydrogels as rectal drug delivery vessels to treat ulcerative colitis.

Mucoadhesive drug delivery systems stick to mucosal tissues and prolong the local retention time of drugs. Since the colon is covered by a mucosal layer, mucoadhesive rectal formulations may improve treatment of such diseases as hypertension or colon cancer. Ulcerative colitis (UC) is an inflammatory bowel disease characterized by chronic inflammation of the colonic mucosa. It is commonly treated with sulfasalazine (SSZ), which is metabolized by the intestinal flora into the therapeutic 5-aminosalicylic acid (5-ASA) and a toxic by-product sulfapyridine (SP). SSZ can be administered orally or rectally. The latter route avoids unintended absorption of the drug or its degradation products in the upper gastrointestinal tract, but often fails due to limited retention time. Here, we propose a mucoadhesive hydrogel to improve the efficacy of rectal SSZ administration. The gel is made of catechol modified-chitosan (Cat-CS) crosslinked by genipin. After loading the gel with SSZ, we evaluated its efficacy in a mouse model of UC. Compared to oral SSZ treatment, rectal SSZ/Cat-CS delivery was more therapeutic, showed equivalent histological scores, and induced a lower plasma concentration of the potentially toxic SP by-product. These results show SSZ/Cat-CS rectal hydrogels are more effective and safer formulations for UC treatment than oral SSZ. STATEMENT OF SIGNIFICANCE: Ulcerative colitis affects the colon by causing chronic inflammation on the mucosa. One of the most common drugs to treat mild to moderate UC is sulfasalazine, which can be administrated both orally and rectally. Rectal formulations are preferable, since their therapeutic effect happens topically, and they prevent side effects related to absorption of the drug in the small intestine. However, the efficacy of rectal sulfasalazine formulations is decreased by their limited colon residence time. Here we propose a chitosan-catechol mucoadhesive gel that allows delivering sulfasalazine more effectively and safely than oral administration. Our results bring new insights into the field of mussel-inspired catechol hydrogels, showing their potential as drug delivery systems to treat a widespread disease such as ulcerative colitis.

[Knockdown of Grb7 inhibits growth of oral squamous cell carcinoma, cell proliferation and promoted apoptosis through ERK/FOXM1 pathway].

PURPOSE: To investigate the effect of growth factor receptor-bound 7 (Grb7) on oral squamous cell carcinoma growth and tumor xenografts. METHODS: Cal27 and hNOK cells were cultivated, real-time PCR and Western blotting were used to detect the expression of Grb7 in hNOK and Cal27. Cal27 was transfected with Grb7 siRNA for 48 h, cell proliferation was assayed using MTT. Flow cytometry was used to determine the cell cycle and apoptosis. Western blot was used to evaluate the expression of caspase3, Bax, bcl-2, Cyclin D1, Rb, E2F1, ERK and FOXM1. Grb7 siRNA and negative control were designed and injected subcutaneously into the mice, tumor volume and weight were measured. Statistical analysis was performed using SPSS 11.0 software package. RESULTS: Grb7 was highly expressed in Cal27 compared with hNOK. Depletion of Grb7 significantly inhibited cell proliferation, blocked G1/S phase transition, promoted cell apoptosis. Knockdown of Grb7 suppressed the expression of Cyclin D1 and Rb, upregulated E2F1 expression. Moreover, c-caspase 3 and Bax was also reduced after inhibition of Grb7. ERK/FOXM1 signaling pathway was also inhibited by Grb7. In addition, the volume and weight of tumor xenografts were reduced by siGrb7. CONCLUSIONS: Depletion of Grb7 inhibits cell proliferation, promotes apoptosis and reduces tumor xenografts through ERK/FOXM1 pathway.

In vitro cell proliferation evaluation of porous nano-zirconia scaffolds with different porosity for bone tissue engineering.

The selection of scaffold materials and the optimization of scaffold morphological and mechanical properties are critical for successful bone tissue engineering. We fabricated porous scaffolds of nano-sized zirconia using a replication technique. The study aimed to explore the relationship between porosity, pore size, mechanical strength, cell adhesion, and cell proliferation in the zirconia scaffolds. Macro- and micro-structures and compressive strength were comparatively tested. Beagle bone marrow stromal cells were seeded onto the scaffolds to evaluate cell seeding efficiency and cell proliferation profile over 14 d of incubation. The zirconia scaffolds presented a complex porous structure with good interconnectivity of pores. By increasing the sinter cycles, the porosity and pore size of the scaffolds decreased, with mean values ranging from 92.7-68.0% and 830-577 µm, respectively, accompanied by increased compressive strengths of 0.6-4.4 MPa. Cell seeding efficiency and cell proliferation over the first 7 d of incubation increased when the porosity decreased, with cell viability highest in the scaffold with a porosity of 75.2%. After 7 d of incubation, the cell proliferation increased when the porosity increased, highest in the scaffolds with a porosity of 92.7%. These results showed that the zirconia scaffold with a porosity of 75.2% possesses favorable mechanical and biological properties for future applications in bone tissue engineering.