Xiaojianzhong decoction prevents gastric precancerous lesions in rats by inhibiting autophagy and glycolysis in gastric mucosal cells

BACKGROUND Gastric precancerous lesions(GPL)precede the development of gastric cancer(GC).They are characterized by gastric mucosal intestinal metaplasia and dysplasia caused by various factors such as inflammation,bacterial infection,and injury.Abnormalities in autophagy and glycolysis affect GPL progression,and their effective regulation can aid in GPL treatment and GC prevention.Xiaojianzhong decoction(XJZ)is a classic compound for the treatment of digestive system diseases in ancient China which can inhibit the progression of GPL.However,its specific mechanism of action is still unclear.AIM To investigate the therapeutic effects of XJZ decoction on a rat GPL model and the mechanisms underlying its effects on autophagy and glycolysis regulation in GPLs.METHODS Wistar rats were randomly divided into six groups of five rats each and all groups except the control group were subjected to GPL model construction for 18 wk.The rats’body weight was monitored every 2 wk starting from the beginning of modeling.Gastric histopathology was examined using hematoxylin-eosin staining and Alcian blue-periodic acid-Schiff staining.Autophagy was observed using transmission electron microscopy.The expressions of autophagy,hypoxia,and glycolysis related proteins in gastric mucosa were detected using immunohistochemistry and immunofluorescence.The expressions of the following proteins in gastric tissues:B cell lymphoma/Leukemia-2 and adenovirus E1B19000 interacting protein 3(Bnip-3),microtubule associated protein 1 light chain 3(LC-3),moesin-like BCL2-interacting protein 1(Beclin-1),phosphatidylinositol 3-kimase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),p53,AMP-activated protein kinase(AMPK),and Unc-51 like kinase 1(ULK1)were detected using western blot.The relative expressions of autophagy,hypoxia,and glycolysis related mRNA in gastric tissues was detected using reverse transcription-polymerase chain reaction.RESULTS Treatment with XJZ increased the rats’body weight and improved GPL-related histopathological manifestations.It also decreased autophagosome and autolysosome formation in gastric tissues and reduced Bnip-3,Beclin-1,and LC-3II expressions,resulting in inhibition of autophagy.Moreover,XJZ down-regulated glycolysis-related monocarboxylate transporter(MCT1),MCT4,and CD147 expressions.XJZ prevented the increase of autophagy level by decreasing gastric mucosal hypoxia,activating the PI3K/AKT/mTOR pathway,inhibiting the p53/AMPK pathway activation and ULK1 Ser-317 and Ser-555 phosphorylation.In addition,XJZ improved abnormal gastric mucosal glucose metabolism by ameliorating gastric mucosal hypoxia and inhibiting ULK1 expression.CONCLUSION This study demonstrates that XJZ may inhibit autophagy and glycolysis in GPL gastric mucosal cells by improving gastric mucosal hypoxia and regulating PI3K/AKT/mTOR and p53/AMPK/ULK1 signaling pathways,providing a feasible strategy for the GPL treatment.

The mucosal immune system in the oral cavity——an orchestra of T cell diversity

The mucosal immune system defends against a vast array of pathogens, yet it exhibits limited responses to commensal microorganisms under healthy conditions. The oral-pharyngeal cavity, the gateway for both the gastrointestinal and respiratory tracts, is composed of complex anatomical structures and is constantly challenged by antigens from air and food. The mucosal immune system of the oral-pharyngeal cavity must prevent pathogen entry while maintaining immune homeostasis, which is achieved via a range of mechanisms that are similar or different to those utilized by the gastrointestinal immune system. In this review, we summarize the features of the mucosal immune system,focusing on T cell subsets and their functions. We also discuss our current understanding of the oral-pharyngeal mucosal immune system.

Effect of bile salts and bile acids on human gastric mucosal epithelial cells

Objective：To explore the effect of bile salt and bile acid on cultured eternalized human gastric mucosa epithelium GES-1 cells. Methods：Cultured eternalized human gastric mucosa epithelium GES-1 cells were treated with media containing 6 different kinds of bile salts and 3 different kinds of bile acids and their mixture with different concentrations： GCDC（glycochenodeoxychoμte）, GDC （glycodeoxychoμte）, GC（glycochoμte）, TCDC（taurochenodeoxychoμte）, TDC（taurodeoxychoμte）, TC （taurochoμte）, LCA （lithocholicacid）, CA（cholic acid）, DCA（deoxycholic acid）（50 μ mol/L,250 μ mol/L,500 μ mol/L,1000 μ mol/L）, DY（mixture of bile salts） and DS（mixture of bile acids）（250 μ mol/L,500 μ mol/L,1000 μ mol/L,1500 μ mol/L, 2000 μ mol/L）, in comparison with the control group（in normal media without bile salts and bile acids）. Cell proliferation was assessed by MTT（3-[4,5-Dimethylthiaolyl]-2,5- diphenyl-tetrazolium bromide） assay for 72 hours with different concentrations and the apoptotic cells were assayed by flow cytometry （FCM） with Annex V-FITC conjugated with propidium iodide（PI） staining for 24 hours with different concentrations（1500,2000 μt mol/L）. Results：There was no significant difference in morphology and cell proliferation in GC group after 24-72 h. Low concentration（50 μ mol/L） of GCDC, GDC, TCDC, TDC and TC accelerated gastric epithelial cell growth in a dosage-time dependent manner. At middle concentration （250-500 μ mol/L）, it showed positive effect after 24-48 h, while negative effect after 72 h. At high concentration（1000 μ mol/L）, it accelerated gastric epithelial cell growth after 24h and show consistent inhibition even leading to necrosis after 48-72 h. LCA and CA showed a positive effect on the concentration of 50 μ mol/L after 24-72 h, while 250-1000 μ mol/L showed a trend towards apoptosis after 24-72 h. At 50-500 μmol/L, DCA showed proliferation after 24 h and apoptosis after 48-72 h, but showed necrosis after 24-72 h at 1000 μmol/L. DY and DS could facilitate normal gastric mucosa epithelial cell growth at low concentration （250-500 μ mol/L）, however at 1000-2000 μ mol/L the trend shifted from apoptosis to necrosis. FCM with Annexin-V conjugated with PI staining revealed that GCDC, GDC, GC, TCDC, TDC, TC, LCA, CA, DCA, DY and DS induced apoptosis of human gastric mucosal epithelial cells. They were all significantly higher than that of the control（P 〈 0.05）, but there was no significant difference in GC group （P 〉 0.05）. The bile salts induced apoptosis in a time-dose-dependent manner. Conclusion：Our results suggested that bile acid and bile salt is the trigger of injury in human gastric mucosal epithelial cells.

Lymph Node Metastasis in Early Signet Ring Cell Carcinoma:Endoscopic Mucosal Resection

Objective： To identify clinicopathological factors predictive of lymph node metastases （LNM） in early signet ring cell carcinoma （SRC）, and further to expand the possibility of using endoscopic mucosal resection （EMR） for the treatment of early SRC. Methods： Data from 27 surgically treated patients with early SRC were collected, and the association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. Results： In the univariate analysis, a tumor larger than 3.0 cm, submucosal invasion, and the presence of lymphatic vessel involvement （LVI） were significantly associated with a higher rate of LNM （all P〈0.05）. In the multivariate model, the presence of LVI was found of to be an independent pathological risk factor for LNM. There was no LNM in 14 patients without the three clinicopathological risk factors （a tumor larger than 3.0 cm, submucosal invasion, and the presence of LVI）. Conclusion： EMR alone may be sufficient treatment for intramucosal early SRC if the tumor is less than or equal to 3.0 cm in size, and when LVI is absent upon postoperative histological examination. When specimens show LVI, an additional radical gastrectomy with lymphadenectomy should be recommended.

Bile salts inhibit growth and induce apoptosis of culture human normal esophageal mucosal epithelial cells

AIM: To investigate the effect of six bile salts:glycocholate (GC), glycochenodeoxycholate (GCDC),glycodeoxycholate (GDC), taurocholate (TC),taurochenodeoxycholate (TCDC), taurodeoxycholate (TDC), and their mixture on cultured human normal esophageal mucosal epithelial cells.METHODS: Human normal esophageal mucosal epithelial cells were cultured with serum-free keratinocyte medium. 3-[4,5-Dimethylthiaolyl]-2,5-diphenyl-tetrazolium bromide assay was applied to the detection of cell proliferation. Apoptotic morphology was observed by phase-contrast video microscopy and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Sub-G1 DNA fragmentations and early apoptotic cells were assayed by flow cytometry (FCM) with propidium iodide (PI) staining and annexin V-FITC conjugated with PI staining.Apoptotic DNA ladders on agarose gel electrophoresis were observed.RESULTS: Except for GC, GCDC, GDC, TC, TCDC, TDC and their mixture could initiate growth inhibition of esophageal mucosal epithelial cells in a dose- and time-dependent manner. TUNEL and FCM assays demonstrated that the bile salts at 500 μmol/L and their mixture at 1 500 μmol/L induced apoptosis except for GC. The percentage of sub-G1 detected by FCM with PI staining was 83.5% in cells treated with 500μmol/L TC for 2 h, and 19.8%, 20.4%, 25.6%, 13.5%, and 75.8% in cells treated with 500 μmol/L GCDC, TCDC, GDC,TDC, and 1 500 μmol/L mixture for 24 h, respectively,which were higher than that of the control (1.5%). The percentage was 1.4% in cells with 500 μmol/L GC for 24 h.DNA ladders on agarose gel electrophoresis were seen in cells treated with 500 μmol/L TC for 2 h and 1 500 μmol/Lmixture for 24 h.CONCLUSION: All GCDC, GDC, TC, TCDC, TDC and their mixture can inhibit growth and induce apoptosis of cultured human normal esophageal mucosal epithelial cells, but GC is well tolerated by the cells.

Granular Cell Tumor of the Esophagus: A Patient Treated by Endoscopic Mucosal Resection with Long Term Follow-Up

Granular cell tumors (GCTs) of the esophagus are uncommon. We report a case of granular cell tumor of esophagus treated by endoscopic mucosal resection (EMR) with long term follow-up.

Role of mucosal dendritic cells in inflammatory bowel disease

The gastrointestinal innate and adaptive immune system continuously faces the challenge of potent stimuli from the commensal microflora and food constituents. These local immune responses require a tight control, the outcome of which is in most cases the induction of tolerance. Local T cell immunity is an important compartment of the specif ic intestinal immune system. T cell reactivity is programmed during the initial stage of its activation by professional presenting cells. Mucosal dendritic cells (DCs) are assumed to play key roles in regulating immune responses in the antigen-rich gastrointestinal environment. Mucosal DCs are a heterogeneous population that can either initiate (innate and adaptive) immune responses, or control intestinal inflammation and maintain tolerance. Defects in this regulation are supposed to lead to the two major forms of inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC). This review will discuss the emerging role of mucosal DCs in regulating intestinal inflammation and immune responses.

Erythropoietin -induced proliferation of gastric mucosal cells

瞄准：在胃的标本上分析红细胞生成素受体的本地化并且用一个猪的胃的上皮的房间文化模型在正常胃的上皮的增长上描绘红细胞生成素的效果。方法：红细胞生成素受体被 RT-PCR，西方的弄污和 immunohistochermistry 检测。有教养的胃的粘膜房间上的红细胞生成素的生长刺激效果被 ELISA 用 bromodeoxyuridine (BrdU ) 决定。结果：红细胞生成素受体在有教养的猪的胃的粘膜上皮细胞上被检测。红细胞生成素受体也在胃的粘膜上皮的底组织化学地被检测。BrdU 试金由红细胞生成素的管理在有教养的猪的胃的粘膜上皮细胞的生长潜力表明了剂量依赖者增加，以及这些效果被反的管理禁止 -- 红细胞生成素抗体(P【0.01 ) 。结论：这些调查结果显示红细胞生成素有一个潜力增殖经由红细胞生成素的胃的粘膜上皮受体。

Enhanced expression of epidermal growth factor receptor gene in gastric mucosal cells by the serum derived from rats treated with electroacupuncture at stomach meridian acupoints

AIM: To investigate the effect of serum derived from rats treated with electroacupuncture at stomach meridian acupoints on the expression of epidermal growth factor receptor (EGFR) gene in gastric mucosal cells. METHODS: The stress-induced gastric mucosal injury in rat model was established by water-immersion and restrained stress methods. 52 rats were randomly divided into: normal group (n = 8), model group (n = 8), model serum group (n = 12), stomach serum group (n = 12), and gallbladder serum group (n = 12). The gastric mucosal cells were separated by pronase-EDTA digestion method and incubated with serum. The EGFR gene expression in gastric mucosal cells was detected by reverse transcription-polymerase chain reaction (RT-PCR) method. RESULTS: Compared with normal group (0.6860 ± 0.0594), the serum derived from rats of the stomach group (1.2272 ± 0.0813, P = 0.00 < 0.01) and gallbladder group (0.9640 ± 0.0387, P = 0.00 < 0.01) had a tendency to enhance the EGFR gene expression in gastric mucosal cells. Such tendency existed in the model group (0.7104 ± 0.0457) but with no signifi cant difference (P = 0.495 > 0.05) and in model serum group (0.8516 ± 0.0409) with an extremely obvious difference (P = 0.001 < 0.01). Furthermore, the EGFR gene expression in stomach serum group was significantly higher than that in gallbladder serum group (P = 0.00 < 0.01). CONCLUSION: The present study shows that serumderived from rats treated with electroacupuncture at stomach meridian acupoints can distinctly increase the EGFR gene expression of gastric mucosal cells. Therefore, there is certain meridian specificity in the serum, which could provide a proof for the TCM theory “particular relation between meridian and internal organ”.

Cysteamine increases expression and activity of H^1-K^+-ATPase of gastric mucosal cells in weaning piglets

AIM: To determine the in vivo andin vivo effects of cysteamine (CS) on expression and activity of H+-K+-ATPase of gastric mucosal cells in weaning piglets.METHODS: Eighteen litters of newborn Xinhuai piglets were employed in the in vivo experiment and allocated to control and treatment groups. From 12 d of age (D12), piglets in control group were fed basal diet, while the treatment group received basal diet supplemented with 120 mg/kg CS. Piglets were weaned on D35 in both groups. Six piglets from each group (n = 6) were slaughtered on D28 (one week before weaning), D35(weaning), D36.5, D38, D42, and D45 (36 h, 72 h,one week and 10 d after weaning), respectively. Semiquantitative RT-PCR was performed todetermine the levels of H+-K+-ATPase mRNA in gastric mucosa. H+-K+-ATPase activity in gastric mucosa homogenate was also determined. Gastric mucosal epithelial cells from piglets through primary cultures were used to further elucidate the effect of CS on expression and activity of H+-K+-ATPase in vivo. Cells were treated for 20 h with 0.001,0.01, and 0.1 mg/mL of CS (n = 4), respectively. The mRNA expression of H+-K+-ATPase and somatostatin (SS)as well as the H+-K+-ATPase activity were determined.RESULTS: in vivo, both mRNA expression and activity of H+-K+-ATPase in gastric mucosa of control group exhibited a trend to increase from D28 to D45, reaching a peak on D45, but did not show significant age differences. Furthermore, neither the mRNA expression nor the activity of H+-K+-ATPase was affected significantly by weaning. CS increased the mRNA expression of H+-K+-ATPase by 73%, 53%, 30% and 39% on D28(P = 0.014), D35 (P = 0.017), D42 (P = 0.013) and D45(P = 0.046), respectively. In accordance with the mRNA expression, H+-K+-ATPase activities were significantly higher in treatment group than in control group on D35(P = 0.043) and D45 (P = 0.040). In vivo, CS exhibited a dose-dependent effect on mRNA expression and activity of H+-K+-ATPase. Both H+-K+-ATPase mRNA expression and activity in gastric mucosal epithelial cells were significantly elevated after 20 h of exposure to the moderate (H+-K+-ATPase expression: P=0.03; H+-K+-ATPase activity: P = 0.014) and high concentrations (H+-K+-ATPase expression: P=0.017; H+-K+-ATPase activity:P = 0.022) of CS. Significant increases in SS mRNA expression were observed to accompany the elevation of H+-K+-ATPase expression and activity induced by the moderate (P = 0.024) and high concentrations (P = 0.022) of CS. Low concentration of CS exerted no effects either on expression and activity of H+-K+-ATPase or on SS mRNA expression in cultured gastric mucosal epithelial cells.CONCLUSION: No significant changes are observed in mRNA expression and activity of H+-K+-ATPase in gastric mucosa of piglets around weaning from D28 to D45. CS increases expression and activity of gastric H+-K+-ATPase in vivo and in vivo. SS is involved in mediating the effect of CS on gastric H+-K+-ATPase expression and activity in weaning piglets.

Nomograms and prognosis for superficial esophageal squamous cell carcinoma

In recent years,endoscopic resection,particularly endoscopic submucosal dis-section,has become increasingly popular in treating non-metastatic superficial esophageal squamous cell carcinoma(ESCC).In this evolving paradigm,it is crucial to identify factors that predict higher rates of lymphatic invasion and poorer outcomes.Larger tumor size,deeper invasion,poorer differentiation,more infiltrative growth patterns(INF-c),higher-grade tumor budding,positive lymphovascular invasion,and certain biomarkers have been associated with lymph node metastasis and increased morbidity through retrospective reviews,leading to the construction of comprehensive nomograms for outcome prediction.If validated by future prospective studies,these nomograms would prove highly applicable in guiding the selection of treatment for superficial ESCC.

Effects of Estrogen on Mucosal Structure and Numbers and Distribution of Intraepithelial Lymphocytes and Goblet Cells in Small Intestine of Rats

To study the effects of estrogen on the structure of the intestinal mucosal barrier, 18 healthy female Wistar Rats underwent estrus synchronization. In diestrus, they were divided into three groups： one sham operated control group （SHAM） ; one ovariec- tomized group （OVX） ; and one ovariectomized plus estradiol benzoate group （ OVX ＋ E2 ）. Intestinal mu- cosal epithelial cells, intraepithelial lymphocytes （[EL）, and goblet cells （GCs） were observed by light microscope. The results showed that in the OVX group, the intestinal mucosa damaged obviously, the villus atrophied, the ratio of villus height to crypt depth reduced, and the number of IELs and GCs re- duced. The indicators of OVX ＋ Ez group were signif- icantly higher than OVX group, but some indicators were lower than SHAM. These indicated that the function of intestinal mucosal barrier was greatly dam- aged in ovariectomied rat, and proper dosage of estra- diol benzoate Would improve the function of small in- testinal mucosal barrier in ovariectomied rat to some degree.

Mucosal-associated invariant T cells from induced pluripotent stem cells:A novel approach for modeling human diseases

Mice have frequently been used to model human diseases involving immune dysregulation such as autoimmune and inflammatory diseases.These models help elucidatethe mechanisms underlying the disease and in the development of novel therapies.However,if mice are deficient in certain cells and/or effectors associated with human diseases,how can their functions be investigated in this species?Mucosal-associated invariant T(MAIT)cells,a novel innate-like T cell family member,are a good example.MAIT cells are abundant in humans but scarce in laboratory mice.MAIT cells harbor an invariant T cell receptor and recognize nonpeptidic antigens vitamin B2metabolites from bacteria and yeasts.Recent studies have shown that MAIT cells play a pivotal role in human diseases such as bacterial infections and autoimmune and inflammatory diseases.MAIT cells possess granulysin,a human-specific effector molecule,but granulysin and its homologue are absent in mice.Furthermore,MAIT cells show poor proliferation in vitro.To overcome these problems and further our knowledge of MAIT cells,we have established a method to expand MAIT cells via induced pluripotent stem cells(iP SCs).In this review,we describe recent advances in the field of MAIT cell research and our approach for human disease modeling with iP SCderived MAIT cells.

Estimating Fatty Acid Composition of Infant Buccal Mucosal Cells by Capillary Gas Chromatography

Long chain polyunsaturated fatty acids,i.e., docosahexaenoic acid (DHA or C22∶6n-3), arachidonic acid (AA or C20∶4n-6) have been identified as essential fatty acids and play an important role in growth and development of infants. Measurement of fatty acid composition is usually by collection of blood, but to obtain blood in infants is difficult. Nowadays, the fatty acid composition can be estimated by collecting buccal mucosal cells, which can avoid repeated blood sampling. The purpose of this paper is to compare the fatty acid composition of cheek cells with that of plasma and red blood cells (RBCs). In this study, twenty-seven infants were enrolled, and buccal mucosal cells and blood samples were obtained from these infants of the same time. Fatty acid composition of buccal mucosal cells, plasma and RBCs were measured by capillary gas chromatography. The results show that the contents of AA and DHA in the buccal mucosal cells are correlated well with that in the plasma [r=0.36 (P=0.042) and r=0.38 (P=0.033), respectively]. The ratio of AA to DHA is 1.32% in buccal mucosal cells, 1.60% in plasma and 1.55% in RBCs and there are no significant differences among groups (P=0.134). It shows that the fatty acid composition in buccal mucosal cells can reflect the fat nutrition status in infants and can be detected by capillary gas chromatography. Estimating fatty acid composition of buccal mucosal cells in infants by capillary gas chromatography is feasible, and because of its noninvasiveness, it can be suitable for nutrition research in infants.

A Rat Model of Autologous Oral Mucosal Epithelial Transplantation for Corneal Limbal Stem Cell Failure

Purpose: To establish an animal model of autologous oral mucosa grafting for limbal stem cell deficiency.Methods: The study was carried from August to October2012. Fourteen SD rats were randomly and evenly allocated to study group A and control group B. Limbal stem cell deficiency was established by alkali burn in the right eye of each rat in both groups. Rats in group A received autologous oral mucosa strip transplantation following the chemical burn. Rats in group B did not receive surgery after the chemical burn.Topical antibiotics and dexamethasone were used in all rats.Corneal clarity, corneal fluorescein staining, oral mucosal graft survival, and complications at postoperative days 1,3,7,14 were observed.Results: The oral mucosa strip graft was detached in one rat in group A. Reepithelialization was observed starting from the graft position and was completed within 14 days in the remaining 6 eyes in group A. However, persistent corneal epithelium defect was observed in all eyes in group B, among which corneal melting and perforation was observed in 2 eyes and corneal opacification with neovascularization was observed in the remaining 5 eyes.Conclusion: Autologous oral mucosa strip grafting for limbal stem cell deficiency can be achieved by a rat model following chemical burn. The fate of the transplanted oral mucosal epithelial cells warrants further study.

Fecal lactoferrin accurately reflects mucosal inflammation in inflammatory bowel disease

BACKGROUND Studies have demonstrated a potential role for fecal biomarkers such as fecal calprotectin(FC)and fecal lactoferrin(FL)in monitoring inflammatory bowel diseases(IBD)-Crohn's disease(CD)and ulcerative colitis(UC).However,their correlation to endoscopic scores,disease severity and affected intestinal surface has not been extensively investigated.AIM To correlate FL,and for comparison white blood cell(WBC)and C-reactive protein(CRP),with endoscopic scores,disease extent and location in CD and UC.METHODS Retrospective analysis in 188 patients who had FL,CRP and WBC determined within 30 d of endoscopy.Disease location,disease extent(number of intestinal segments involved),disease severity(determined by endoscopic scores),timing of FL testing in relation to colonoscopy,as well as the use of effective fast acting medications(steroids and biologics)between colonoscopy and FL measurement,were recorded.RESULTS In 131 CD and 57 UC patients,both CRP and FL-but not WBC-distinguished disease severity(inactive,mild,moderate,severe).In patients receiving fastacting(steroids or biologics)treatment in between FL and colonoscopy,FL showed a higher correlation to endoscopic scores when tested before vs after the procedure(r=0.596,P<0.001,vs r=0.285,P=0.15 for the Simple Endoscopic Score for CD;and r=0.402,P=0.01 vs r=0.054 P=0.84 for Disease Activity Index).Finally,FL was significantly correlated with the diseased mucosal surface(colon-ileocolon>small bowel)and the number of inflamed colon segments.CONCLUSION FL and CRP separated disease severity categories with FL showing lower discriminating P-values.FL showed a close correlation with the involved mucosal surface and with disease extent and was more closely correlated to endoscopy when determined before the procedure–this indicating that inflammatory activity changes associated with therapy might be rapidly reflected by FL levels.FL can accurately and timely characterize intestinal inflammation in IBD.

Prevention of esophageal strictures after endoscopic submucosal dissection

Endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma and dysplasia of Barrett's esophagus.However,the large defects in the esophageal mucosa often cause severe esophageal strictures,which dramatically reduce the patient's quality of life.Although preventive endoscopic balloon dilatation can reduce dysphagia and the frequency of dilatation,other approaches are necessary to prevent esophageal strictures after ESD.This review describes several strategies for preventing esophageal strictures after ESD,with a particular focus on anti-inflammatory and tissue engineering approaches.The local injection of triamcinolone acetonide and other systemic steroid therapies are frequently used to prevent esophageal strictures after ESD.Tissue engineering approaches for preventing esophageal strictures have recently been applied in basic research studies.Scaffolds with temporary stents have been applied in five cases,and this technique has been shown to be safe and is anticipated to prevent esophageal strictures.Fabricated autologous oral mucosal epithelial cell sheets to cover the defective mucosa similarly to how commercially available skin products fabricated from epidermal cells are used for skin defects or in cases of intractable ulcers.Fabricated autologous oralmucosal-epithelial cell sheets have already been shown to be safe.

Mucosal COVID-19 vaccines:Risks,benefits and control of the pandemic

Based on mucosal immunization to promote both mucosal and systemic immune responses,next-generation coronavirus disease 2019(COVID-19)vaccines would be administered intranasally or orally.The goal of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)vaccines is to provide adequate immune protection and avoid severe disease and death.Mucosal vaccine candidates for COVID-19 including vector vaccines,recombinant subunit vaccines and live attenuated vaccines are under development.Furthermore,subunit protein vaccines and virus-vectored vaccines have made substantial progress in preclinical and clinical settings,resulting in SARS-CoV-2 intranasal vaccines based on the previously successfully used nasal vaccines.Additional to their ability to trigger stable,protective immune responses at the sites of pathogenic infection,the development of‘specific’mucosal vaccines targeting coronavirus antigens could be an excellent option for preventing future pandemics.However,their efficacy and safety should be confirmed.

Endoscopic Mucosal Resection

Endoscopic mucosal resection is indicated in limited esophageal carcinomas with in?ltration of the mucosa. As submucosal cancer is combined with a rate of lymph node metastasis in up to 30% mucosectomy is not the procedure of choice. The main techniques of endoscopic mucosal resection are the “suck and cut” technique using a cap on the endoscope or a ligation device to create a pseudocroup of the carcinoma. Submucosal injection of saline or other solutions is recommended prior to diathermic mucosectomy in order to reduce the risk of perforation or haemorrhage. The long term results of endoscopic mucosal resection show tumor speci?c 5 year survival rates of about 97% especially if the indication is restricted to m1 and m2 mucosal carcinomas.

Intestinal mucosal barrier in functional constipation:Dose it change?

BACKGROUND The intestinal mucosal barrier is the first line of defense against numerous harmful substances,and it contributes to the maintenance of intestinal homeostasis.Recent studies reported that structural and functional changes in the intestinal mucosal barrier were involved in the pathogenesis of several intestinal diseases.However,no study thoroughly evaluated this barrier in patients with functional constipation(FC).AIM To investigate the intestinal mucosal barrier in FC,including the mucus barrier,intercellular junctions,mucosal immunity and gut permeability.METHODS Forty FC patients who fulfilled the Rome IV criteria and 24 healthy controls were recruited in the Department of Gastroenterology of China-Japan Friendship Hospital.The colonic mucus barrier,intercellular junctions in the colonic epithelium,mucosal immune state and gut permeability in FC patients were comprehensively examined.Goblet cells were stained with Alcian Blue/Periodic acid Schiff(AB/PAS)and counted.The ultrastructure of intercellular junctional complexes was observed under an electron microscope.Occludin and zonula occludens-1(ZO-1)in the colonic mucosa were located and quantified using immunohistochemistry and quantitative real-time polymerase chain reaction.Colonic CD3+intraepithelial lymphocytes(IELs)and CD3+lymphocytes in the lamina propria were identified and counted using immunofluorescence.The serum levels of D-lactic acid and zonulin were detected using enzyme-linked immunosorbent assay.RESULTS Compared to healthy controls,the staining of mucus secreted by goblet cells was darker in FC patients,and the number of goblet cells per upper crypt in the colonic mucosa was significantly increased in FC patients(control,18.67±2.99;FC,22.42±4.09;P=0.001).The intercellular junctional complexes in the colonic epithelium were integral in FC patients.The distribution of mucosal occludin and ZO-1 was not altered in FC patients.No significant differences were found in occludin(control,5.76E-2±1.62E-2;FC,5.17E-2±1.80E-2;P=0.240)and ZO-1(control,2.29E-2±0.93E-2;FC,2.68E-2±1.60E-2;P=0.333)protein expression between the two groups.The mRNA levels in occludin and ZO-1 were not modified in FC patients compared to healthy controls(P=0.145,P=0.451,respectively).No significant differences were observed in the number of CD3+IELs per 100 epithelial cells(control,5.62±2.06;FC,4.50±2.16;P=0.070)and CD3+lamina propria lymphocytes(control,19.69±6.04/mm^(2);FC,22.70±11.38/mm^(2);P=0.273).There were no significant differences in serum D-lactic acid[control,5.21(4.46,5.49)mmol/L;FC,4.63(4.31,5.42)mmol/L;P=0.112]or zonulin[control,1.36(0.53,2.15)ng/mL;FC,0.94(0.47,1.56)ng/mL;P=0.185]levels between FC patients and healthy controls.CONCLUSION The intestinal mucosal barrier in FC patients exhibits a compensatory increase in goblet cells and integral intercellular junctions without activation of mucosal immunity or increased gut permeability.