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1.
Medicine (Baltimore) ; 99(7): e19090, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32049812

RESUMO

Jaw phosphaturic mesenchymal tumors (PMTs) are a rare neoplasm with uncertain histogenesis. This study aimed to clarify the clinical and pathological features of jaw PMTs.We reviewed the clinical records of 39 patients diagnosed with PMTs in the jaws, and investigated clinical and morphologic characteristics, histologic subtypes, and immunophenotypes of all cases.Microscopic analyses revealed 2 major histologic tumor subtypes: "phosphaturic mesenchymal tumors of mixed epithelial and connective tissue" (PMTMECT), and "phosphaturic mesenchymal tumors of mixed connective tissue" (PMTMCT). PMTMECTs and PMTMCTs accounted for 29 and 10 cases of PMTs, respectively. Most PMTMECT diagnoses were made predominantly in males aged <45 years, and the incidence was similar in both the mandible and maxilla. In contrast, patients with PMTMCTs are predominantly females aged ≥45 years, and all tumors were in the mandible. Histologically, PMTMECT had lower cellularity and a more elongated and spindled mesenchymal component with less elaborate intrinsic microvasculature than PMTMCT. Immunohistochemically, the epithelia of all PMTMECTs was immunoreactive for AE1/AE3. Other immunohistochemical staining of PMTMECTs revealed positive expression of vimentin, SATB2, ERG, CD99, Bcl-2, CD56, S-100, D2-40, CD68, SMA, and CD34 in either one or both components. Immunohistochemical staining of PMTMCTs was diffusely positive for vimentin and a varied ratio of positivity for SATB2, ERG, CD99, Bcl-2, CD56, S-100, D2-40, CD68, SMA, and CD34, but negative for AE1/AE3. Most patients were cured by complete resection, except 2 patients who had repeated recurrences, one of which also had multiple metastasis.Jaw PMT can be divided into 2 major histological subtypes. PMTMECTs are more common than are PMTMCTs, and can transform into malignant PMTMCTs during the progression. PMTMECTs were more commonly observed in males and the incidence was similar in both the maxilla and mandible. PMTMCTs were almost always observed in the mandible of females. Compared with PMTMCTs, PMTMECTs have an admixture of epithelial components with less prominent vasculature and lower cellularity. There were no statistically significant differences in the expression of immunohistochemical markers except AE1/AE3 between PMTMECTs and PMTMCTs. However, immunohistochemical markers have great significance for differentiating other mesenchymal tumors.

2.
Phytomedicine ; 68: 153179, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32062328

RESUMO

BACKGROUND: Intestinal epithelial barrier dysfunction, which involves myosin light chain kinase (MLCK) activation, contributes to the occurrence and progression of inflammation in inflammatory bowel disease (IBD). Wogonoside helps maintain intestinal homeostasis in mice with dextran sulfate sodium (DSS)-induced colitis, but it is unclear whether it modulates intestinal barrier function. PURPOSE: Here, we demonstrate that wogonoside protects against intestinal barrier dysfunction in colitis via the MLCK/pMLC2 pathway both in vivo and in vitro. METHODS: Caco-2 cell monolayers treated with the proinflammatory cytokine TNF-α showed barrier dysfunction and were assessed in the absence and presence of wogonoside for various physiological, morphological, and biochemical parameters. Colitis was induced by 3% DSS in mice, which were used as an animal model to explore the pharmacodynamics of wogonoside. We detected MLCK/pMLC2 pathway proteins via western blot analysis, assessed the cytokines IL-13 and IFN-γ via ELISA, tested bacterial translocation via fluorescence in situ hybridization (FISH) and a proper sampling of secondary lymphoid organs for bacterial culture. In addition, the docking affinity of wogonoside and MLCK was observed with DS2.5 software. RESULTS: Wogonoside alleviated the disruption of transepithelial electrical resistance (TER) in TNF-α exposured Caco-2 cell; FITC-dextran hyperpermeability; loss of the tight junction (TJ) proteins occludin, ZO-1 and claudin-1 in Caco-2 cell monolayers; and bacterial translocation in colitic mice. Moreover, wogonoside reduced the levels of the proinflammatory cytokines IL-13 and IFN-γ to maintain intestinal immune homeostasis. Transmission electron microscopy (TEM) confirmed that wogonoside ameliorated the destruction of intestinal epithelial TJs. Wogonoside not only inhibited the cytoskeletal F-actin rearrangement induced by TNF-α, stabilized the cytoskeletal structure, suppressed MLCK protein expression, and reduced MLC2 phosphorylation. In addition, the results of molecular docking analysis showed that wogonoside had a high affinity for MLCK and formed hydrogen bonds with the amino acid residue LYS261 and π bonds with LYS229. CONCLUSION: Collectively, our study indicates that wogonoside alleviates colitis by protecting against intestinal barrier dysfunction, and the potential mechanism may involve regulation of TJs via the MLCK/pMLC2 signaling pathway. Meanwhile, our study also explains the success of S. baicalensis in the treatment of ulcerative colitis (UC).

3.
Acta Pharmacol Sin ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937929

RESUMO

Oroxindin is a flavonoid isolated from the traditional Chinese medicine Huang-Qin, which has shown various pharmacological activities including anti-inflammatory, antitumor, antioxidant, etc. Thus far, the effect of oroxindin on colonic inflammation and the underlying mechanism remain unknown. In this study, we investigated the tissue distribution of oroxindin and its therapeutic effects on ulcerative colitis (UC) as well as the underlying mechanisms. UC model was established in mice by administrating dextran sulfate sodium (DSS) in drinking water for 7 d. We first showed that oroxindin was largely absorbed by the colon as an active ingredient after normal mice received Huang-Qin-Tang, a traditional Chinese medicine decoction. UC mice were then treated with oroxindin (12.5, 25, 50 mg ·kg-1 ·d-1, i.g.) for 10 d. We found that oroxindin treatment greatly suppressed massive macrophages infiltration and attenuated pathological changes in colonic tissue. Furthermore, oroxindin treatment significantly inhibited the generation of IL-1ß and IL-18 in the colon via inhibiting the nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome formation and activation. In cultured macrophages, LPS induced NLRP3 inflammasome formation and caspase-1 activation, which were suppressed by oroxindin (12.5-50 µM). In LPS-treated macrophages, oroxindin dose-dependently restored the expression of TXNIP protein, leading to suppressing TXNIP-dependent NF-κB activation. In conclusion, these results demonstrate that oroxindin could be absorbed by the colon and attenuate inflammatory responses via inhibiting NLRP3 inflammasome formation and activation, which is related to the inhibitory effect on TXNIP-dependent NF-κB-signaling pathway. Hence, oroxindin has the potential of becoming an effective drug for treating UC.

4.
J Sep Sci ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919992

RESUMO

Curcumin widely exists in food, and rapid selective and accurate detection of curcumin have great significance in chemical industry. In this experiment, a new magnetic biocompatibility molecularly imprinted polymer was prepared with non-toxic and biocompatible Zein to adsorb curcumin selectively. The polymer has high biocompatibility, good adsorption capacity, and specific adsorption for curcumin. Combined with portable electrochemical workstations, the polymer can be used to detect curcumin rapidly and cost-effectively. Using curcumin as a template and Zein as the crosslinking agent, the polymers were synthesized on the surface of Fe3 O4 particles for solid phase extraction. The experimental results showed that the polymer reached large adsorption capacity (32.12 mg/g) with fast kinetics (20 mins). The adsorption characteristic of the polymer followed the Langmuir isotherm and pseudo-second-order kinetic models. Hexacyanoferrate was used as electrochemical probe to generate signals, and the linear range was 5-200 ug/mL for measuring curcumin. The experimental analysis showed that the polymer were an ideal material for selective accumulation of curcumin from complex samples. This approach has been successfully applied to the determination of curcumin in food samples with electrochemical detection, indicating that this is a feasible and practical technique. This article is protected by copyright. All rights reserved.

5.
Anal Chem ; 92(3): 2435-2442, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31904935

RESUMO

The process and mechanism of silk degradation is still a bewildering mystery in the investigation and conservation of cultural relics, which rely on the development of accurate and tailored analysis technologies. Here, two advanced approaches, proteomics and immunology, were developed for determining the deterioration behavior of historic silk fabrics and artificially aged samples from the molecular to the holistic level. The surface morphology and secondary structure of silk were destroyed during degradation. Subsequently, the proteomics and immunology analysis demonstrated a new degradation model differing from previous reports. First, the amorphous region and the looser crystalline regions were destroyed together, and the macromolecular chains were broken randomly. Then, the tight ß-sheet blocks in the crystalline region were exposed and deteriorated, which expedited the degradation of tight ß-sheet blocks and relatively loose blocks in the crystalline domain as well as the amorphous domain, ultimately yielding small molecule polypeptides. However, the deterioration process of ancient fabrics could be accelerated by poor burial conditions, thus showing distinct destructive characteristics. Overall, the results gave us a more comprehensive and profound understanding of the degradation process of ancient silk.

6.
Phytopathology ; 110(2): 278-286, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31613175

RESUMO

A characteristic feature of phytopathogenic Xanthomonas bacteria is the production of yellow membrane-bound pigments called xanthomonadins. Previous studies showed that 3-hydroxybenzoic acid (3-HBA) was a xanthomonadin biosynthetic intermediate and also, that it had a signaling role. The question of whether the structural isomers 4-HBA and 2-HBA (salicylic acid) have any role in xanthomonadin biosynthesis remained unclear. In this study, we have selectively eliminated 3-HBA, 4-HBA, or the production of both by expression of the mhb, pobA, and pchAB gene clusters in the Xanthomonas campestris pv. campestris strain XC1. The resulting strains were different in pigmentation, virulence factor production, and virulence. These results suggest that both 3-HBA and 4-HBA are involved in xanthomonadin biosynthesis. When both 3-HBA and 4-HBA are present, X. campestris pv. campestris prefers 3-HBA for Xanthomonadin-A biosynthesis; the 3-HBA-derived Xanthomonadin-A was predominant over the 4-HBA-derived xanthomonadin in the wild-type strain XC1. If 3-HBA is not present, then 4-HBA is used for biosynthesis of a structurally uncharacterized Xanthomonadin-B. Salicylic acid had no effect on xanthomonadin biosynthesis. Interference with 3-HBA and 4-HBA biosynthesis also affected X. campestris pv. campestris virulence factor production and reduced virulence in cabbage and Chinese radish. These findings add to our understanding of xanthomonadin biosynthetic mechanisms and further help to elucidate the biological roles of xanthomonadins in X. campestris pv. campestris adaptation and virulence in host plants.

7.
Mol Plant Microbe Interact ; : MPMI09190264R, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31710580

RESUMO

Phenazine-1-carboxylic acid (PCA) is the primary active component in the newly registered, commercial biopesticide Shenqinmycin and is produced during fermentation by the engineered rhizobacterium strain Pseudomonas PA1201. Both phz1 and phz2 gene clusters contribute to PCA biosynthesis. In this study, we evaluated the role of OxyR in the regulation of PCA biosynthesis in PA1201. We first showed a functional link between oxyR expression and PCA biosynthesis. Deletion of oxyR and overexpression of oxyR both increase PCA biosynthesis. The molecular mechanisms underlying OxyR regulation of PCA production were investigated using several approaches. OxyR acts divergently in phz1 and phz2. Overexpression of oxyR activated the expression of phz1 and phz1-dependent PCA production. However, overexpression of oxyR had little effect on phz2-dependent PCA biosynthesis, while deletion of oxyR promoted phz2-dependent PCA production and exerted a negative effect on phz2 expression. Further, OxyR directly bound to the phz2 promoter region. In addition, the regulation of PCA biosynthesis by OxyR was associated with quorum sensing (QS) systems. Overexpression of OxyR positively regulated pqs QS system. Finally, transcriptomic analysis and subsequent genetic analysis revealed the small RNA phrS plays a key role in OxyR-dependent PCA accumulation. Specifically, OxyR directly binds to the phrS promoter region to positively regulate phrS expression wherein PhrS regulates the PCA positive regulator MvfR in order to control PCA biosynthesis.

8.
ACS Appl Mater Interfaces ; 12(4): 4241-4253, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31859475

RESUMO

Due to the inconvenience of application, risk of extra damage to fragile soft tissues, and the high incidence of late-stage complications, significant research endeavors have been focused on developing safe and effective bioadhesives to replace or assist the traditional suture techniques for wound closure. Here, we describe a fast and high strength bioadhesive based on polysaccharides and peptide dendrimers (OCMC/G3KP) with inherent hemostatic ability and antibacterial properties. Compared with the commercial bioadhesive Coseal, the OCMC/G3KP hydrogel shows a remarkable 5-fold increase in adhesion strength. The in vivo studies further confirm the superior wound healing performance of the OCMC/G3KP hydrogel in contrast with Coseal and conventional sutures. The OCMC/G3KP hydrogels are efficient and biocompatible bioadhesives with precise controllability that could be flexibly modulated to meet diverse clinical demands.

9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(5): 684-687, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31762238

RESUMO

OBJECTIVE: To explore the protective effects of quercetin (QE) on triptolide (TP) induced liver injury and the relevant mechanism. METHODS: Forty C57BL/6 mice were equally divided into 4 groups, control group, TP model group, 20 mg/kg QE treatment group and 80 mg/kg QE treatment group randomly. The 20 mg/kg and 80 mg/kg QE groups were gastrointestinal administration with QE at the dose of 0.2 mL/10 g for 10 d, twice daily, while other groups were administrated with equivalent normal saline. Four hours post the last dose, animals were gastrointestinal administered with TP at a dose of 500 µg/kg per mouse, except for NS control. All the mice were sacrificed 22 h later, blood and liver tissue samples were collected. The pathologic change of liver tissue was detected by HE staining. The level of aminotransferase (AST) and aspartate alanine aminotransferase (ALT) in serum, and the level of glutathione (GSH), malondialdehyde (MDA) and superoxide dismutase (SOD) in liver tissue homogenates were detected using the commercial kits. The level of interleukin (IL)-17, IL-10 and IL-6 in liver tissue homogenates was measured by ELISA. Hepatic expression of Toll-like receptor 4 (TLR4) was detected by Western blot. RESULTS: Compared with the control group, in the TP model group, hepatic lobule structure atrophied and even disappeared, hepatic cell necrosis and inflammatory cell infiltration are obvious. Additionally, in TP model group, serum ALT, AST and MDA levels were significantly increased, SOD and GSH levels were decreased, IL-6 and IL-17 levels were increased, IL-10 levels were decreased, and TLR4 protein levels were increased (P < 0.05). Compared with the TP model group, liver tissue injury and inflammatory cell infiltration were reduced in the QE group, and serum levels of ALT, AST, MDA, IL-6 and IL-17 were all decreased. TLR4 expression was down-regulated (P < 0.05) in both QE groups, and the decease levle was more significant in the high-dose QE group (P < 0.05, compared with the low-dose QE group). CONCLUSION: Quercetin can reduce TP-induced liver injury by reducing oxidative damage, promoting antioxidant and regulating cytokine secretion.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Quercetina/farmacologia , Animais , Antioxidantes/metabolismo , Citocinas/metabolismo , Diterpenos , Compostos de Epóxi , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Fenantrenos , Distribuição Aleatória
11.
J Bone Miner Res ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31643101

RESUMO

Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome. It is curable by excision of the causative tumor. However, a few cases may persist or relapse after tumor resection. We aimed to investigate the rate of these events and related factors. We retrospectively studied TIO patients treated with surgery in a tertiary hospital. TIO was established based on a pathologic examination or the reversion of hypophosphatemia. Refractory TIO patients consisted of those with nonremission or recurrent hypophosphatemia after surgery. A total of 230 patients were confirmed as having TIO. After primary surgery, 26 (11.3%) cases persisted, and 16 (7.0%) cases recurred. The overall refractory rate was 18.3%. The median time of recurrence was 33 months. Compared with patients in the recovery group, patients in the refractory group were more likely to be female (59.5% versus 41.0%, p = .029) and have a lower serum phosphate level (0.44 ± 0.13 versus 0.50 ± 0.11 mmol/L, p = .002). The refractory rate was lowest in head/neck tumors (7.5%) and highest in spine tumors (77.8%). Regarding the tissue involved of tumor location, the refractory rate was higher in tumors involving bone than tumors involving soft tissue (32.7% versus 7.0%, p < .001). The outcomes of malignant tumors were worse than those of benign tumors (p < .001): nonremission rate, 21.4% versus 9.7%; recurrence rate, 28.6% versus 6.5%. In the multivariate regression analysis, female sex, spine tumors, bone tissue-involved tumors, malignancy, and low preoperation serum phosphorus levels were identified as risk factors for refractory outcomes. High preoperative fibroblast growth factor 23 (FGF23) levels were also associated with refractory after adjusting for involving tissue and tumor malignancy. In summary, we are the first to report the rate and clinical characteristics of refractory TIO in a large cohort. For patients with multiple risk factors, especially spine tumors, clinical practitioners should be aware of a poor surgical prognosis. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.

12.
BMC Neurol ; 19(1): 249, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31646971

RESUMO

BACKGROUND: Cardiac myxoma is the most common benign cardiac tumor. Brain metastases or multiple cerebral aneurysms are extremely rare, especially for the case of both complications. Brain metastases are usually found at the same time or few months after the diagnosis or surgical removal of cardiac myxoma CASE PRESENTATION: We describe a case of patient, operated for a cardiac myxoma, who presented multiple central nervous system metastases associated, cerebral aneurysms and subsequent intracerebral hemorrhage CONCLUSIONS: The long-term follow-up of the patients with atrial myxoma even after complete surgical excision is recommended, especially for the patient with central nervous system manifestations before atrial myxoma excision.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Cardíacas/patologia , Aneurisma Intracraniano/etiologia , Mixoma/patologia , Adulto , Hemorragia Cerebral/etiologia , Feminino , Átrios do Coração/patologia , Humanos
13.
J Plast Reconstr Aesthet Surg ; 72(12): 2041-2048, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31562029

RESUMO

OBJECTIVE: Outcomes from surgical repair of transverse facial cleft (macrostomia) may not be very satisfactory when conventional methods are used to position the oral commissure to be repaired. To improve patient outcomes, we developed a modified oral commissure positioning and reconstruction method for transverse facial cleft repair. METHOD: In the modified positioning method, the oral commissure at the abnormal side was positioned precisely and reconstructed by a combination of two conventional methods, namely, the distance measurement method and the anatomical charateristics method. The function of the orbicularis oris muscle was preserved. Postoperative surgical scar score and oral commissure symmetry score were determined and compared between patients and healthy controls. The scores ranged from one to five, with one representing the best and five indicating the worst results. RESULTS: Nine patients aged 4-31 months (7 girls) underwent the modified transverse facial cleft repair surgery. All the patients had unilateral transverse facial cleft with or without microsomia and/or complete cleft lip. The patients were followed up for one to five years. Although average surgical scar scores of patients (close-mouth: 1.8 ± 0.8, range: 1.0-2.8; open-mouth: 1.8 ± 0.9, range 1.0-3.6) remained significantly higher (P < 0.05) than those of the healthy controls (N = 8, close-mouth 1.1 ± 0.4, range: 1.0-1.4, open-mouth: 1.1 ± 0.3, range: 1.0-1.2) 6 months after the surgery, their average close-mouth oral commissure symmetry score (1.9 ± 0.7, range: 1.6-2.8) was similar (P = 0.381) to those of the healthy controls (1.8 ± 0.8, range: 1.0-2.6). CONCLUSIONS: The modified procedure appears to lead to promising long-term benefit on restoring oral commissure symmetry.

15.
J Proteomics ; 209: 103510, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31479798

RESUMO

Achieving efficient identification of silk protein requires highly sensitive analytical techniques and favorable extraction methods, which is of great significance to the research of ancient silk, especially for the controversial issue of the silk origin. In this paper, proteomics and western blot were proposed to analyze the silk proteins of Bombyx mori (B. mori) and Antheraea pernyi (A. pernyi) dissolved by different methods. First, the differences in secondary structure were detected via spectroscopy. LC-MS/MS was then employed to characterize the peptides of silk proteins precisely. LiBr solution exhibited outstanding dissolution effect on B. mori cocoon, with 87 proteins detected; while copper-ethylenediamine solution (CED) was more appropriate for A. pernyi cocoon, and 16 proteins were identified in A. pernyi-CED. In addition to fibroin and sericin, abundant seroins, enzymes, protease inhibitors, other functional proteins and uncharacterized proteins were detected. Based on the LC-MS/MS data, diagnostic antibodies for the two species were prepared, and fibroin was successfully identified by western blot assay because both dissolution methods were gentle and did not destroy the antigenic epitopes in the protein molecule. Owing to their good specificity and high sensitivity, these diagnostic antibodies have good application prospects in immunoassays of different silk species. SIGNIFICANCE: This study presents the comprehensive analysis on silk identification of proteins from B. mori and A. pernyi extracted by different methods via the proteomic and immunology as well as the conventional approaches. Great coverage of two cocoon proteomes was accomplished, which demonstrated the outstanding difference in components and abundance. Based on the proteomics analysis, the diagnostic antibodies against two species were prepared and identified the corresponding fibroin successfully in the completed protein mixtures. To our knowledge, the proteomic and immunology procedures with high efficiency, sensitivity and specificity are novel analysis on the silk identification and has great potential in the field of ancient silk detection.

16.
Acta Crystallogr C Struct Chem ; 75(Pt 9): 1280-1285, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31484817

RESUMO

By employing the semi-rigid multidentate carboxylic acid ligand 4,4',4''-{[(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)]tris(oxy)}tribenzoic acid (denoted H3L), a new lanthanum coordination polymer, namely poly[[bis(dimethylformamide)(µ6-4,4',4''-{[(2,4,6-trimethylbenzene-1,3,5-triyl)tris(methylene)]tris(oxy)}tribenzoato)lanthanum(III)] dimethylformamide tetrasolvate 0.25-hydrate], {[La(C33H27O9)(C3H7NO)2]·4C3H7NO·0.25H2O}n or {[La(L)(DMF)2]·4(DMF)·0.25(H2O)}n (DMF is dimethylformamide) (1), was prepared and characterized by single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, IR spectroscopy and photoluminescence studies. The asymmetric unit contains one LaIII cation, one anionic L3- ligand, two coordinated DMF molecules, four free DMF molecules and one-quarter of a free water molecule. Compound 1 possesses (3,6)-connected two-dimensional kgd topology sheets consisting of secondary building units of La2 clusters and L3- ligands, which further stack into three-dimensional supramolecular networks through π-π interactions. Compound 1 exhibits a photoluminescence emission at room temperature, with a peak at 410 nm, owing to a ligand-centred excited state.

17.
Pharmacol Res ; 148: 104417, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31473343

RESUMO

Intact epithelial barrier and mucosal immune system are crucial for maintaining intestinal homeostasis. Previous study indicated that Dendrobium officinale polysaccharides (DOPS) can regulate immune responses and inflammation to alleviate experimental colitis. However, it remains largely unknown whether DOPS can suppress AOM/DSS-induced colorectal cancer (CRC) model through its direct impact on intestinal barrier function and intestinal mucosal immunity. Here, we demonstrated the therapeutic action of DOPS for CRC model and further illustrated its underlying mechanisms. Treatment with 5-aminosalicylic acid (5-ASA) and DOPS significantly improved the clinical signs and symptoms of chronic colitis, relieve colon damage, suppress the formation and growth of colon tumor in CRC mice. Moreover, administration of DOPS effectively preserved the intestinal barrier function via reducing the loss of zonula occludens-1 (ZO-1) and occludin in adjacent tissues and carcinomatous tissues. Further studies demonstrated that DOPS improved the metabolic ability of tumor infiltrated CD8+ cytotoxic T lymphocytes (CTLs) and reduced the expression of PD-1 on CTLs to enhance the anti-tumor immune response in the tumor microenvironments (TME). Together, the conclusions indicated that DOPS restore intestinal barrier function and enhance intestinal anti-tumor immune response to suppress CRC, which may be a novel strategy for the prevention and treatment of CRC.

18.
Environ Sci Technol ; 53(17): 10102-10109, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31408603

RESUMO

The mobility of pharmaceuticals in environmental systems is under great scrutiny in the scientific literature and in the press. Still, very few reports have focused on redox-driven transformations when these compounds are bound to mineral surfaces, and how their transport is affected under flow-through conditions. In this study, we examined the adsorption and electron transfer reactions of ciprofloxacin (CIP) in a dynamic column containing nanosized hematite (α-Fe2O3). CIP binding and the subsequent redox transformation were strongly dependent on inflow pH and residence time. These reactions could be predicted using transport models that account for adsorption and transformation kinetics. Our results show that flow interruption over a 16 h period triggers oxidation of hematite-bound CIP into byproducts. These reactions are likely facilitated by inner-sphere iron-CIP complexes formed via the sluggish conversion from outer-sphere complexes during interrupted flow. When intermittent flow/no-flow conditions were applied sequentially, a second byproduct was detected in the column effluent. This work sheds light on a much overseen aspect of redox transformations of antibiotics under flow-through conditions. It has important implications in adequately predicting transport, and in developing risk assessments of these emerging compounds in the environment.


Assuntos
Ciprofloxacino , Compostos Férricos , Adsorção , Oxirredução
19.
Anal Sci ; 35(11): 1243-1249, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31353338

RESUMO

The degradation behavior of silk fibroin (SF) is a significant and intriguing subject in the area of archaeological ancient silk research. In the present study, the immunological detection techniques combined with traditional characterization methods, jointly studied the degradation process of SF from Bombyx mori (B. mori) and Antheraea pernyi (A. pernyi) through exposure to alkaline proteinase, α-chymotrypsin, pepsin, and trypsin. Spectroscopic analysis revealed that different enzymes showed similar hydrolysis effects on the secondary structure, but the changes of B. mori SF and A. pernyi SF were mainly reflected in the decrease of ß-sheet and the reduction of α-helical structure, respectively. In further research of immunology, two diagnostic antibodies were prepared corresponding to SF of B. mori and A. pernyi, respectively. The enzyme-linked immunosorbent assay (ELISA) and western blot indicated the enzyme-treated SF proteins still exhibited higher immunoreactivity because the epitopes on the surface of SF molecules are retained. Although α-chymotrypsin possesses the most cleavage sites among these enzymes, the α-chymotrypsin-treated SF did not exhibit significant changes in secondary structures and high antibody binding capacity. The results deepen our understanding of the SF degradation process during enzymatic hydrolysis, and show far-reaching guiding significance in trace detection of SF.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31331893

RESUMO

Visual and semantic saliency are important in image captioning. However, single-phase image captioning benefits little from limited saliency without a saliency predictor. In this paper, a novel saliency-enhanced re-captioning framework via two-phase learning is proposed to enhance the single-phase image captioning. In the framework, visual saliency and semantic saliency are distilled from the first-phase model and fused with the second-phase model for model self-boosting. The visual saliency mechanism can generate a saliency map and a saliency mask for an image without learning a saliency map predictor. The semantic saliency mechanism sheds some lights on the properties of words with part-of-speech Noun in a caption. Besides, another type of saliency, sample saliency is proposed to explicitly compute the saliency degree of each sample, which helps for more robust image captioning. In addition, how to combine the above three types of saliency for further performance boost is also examined. Our framework can treat an image captioning model as a saliency extractor, which may benefit other captioning models and related tasks. The experimental results on both the Flickr30k and MSCOCO datasets show that the saliency-enhanced models can obtain promising performance gains.

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