The importance of fecal nucleic acid detection in patients with coronavirus disease (COVID-19): A systematic review and meta-analysis.

Pooled data from 2352 hospitalized coronavirus disease 2019 (COVID-19) patients with viral RNA in feces across 46 studies were analyzed and the pooled prevalence of fecal RNA was 46.8% (95% confidence interval [CI]: 0.383-0.554). The pooled analysis showed that the occurrence of total gastrointestinal (GI) symptoms was 28.5% (95% CI: 0.125-0.44) in COVID-19 patients with fecal RNA, that of both respiratory and GI symptoms was 21.9% (95% CI: 0.09-0.346), that of only GI symptoms was 19.8% (95% CI: 0.107-0.288), and that of only respiratory symptoms was 50.5%（95% CI: 0.267-0.744). The pooled data showed no significant difference in positive fecal RNA between severe and nonsevere cases (odds ratio = 2.009, p = 0.079, 95% CI: 0.922-4.378). During hospital admission, after samples from the respiratory system tested negative for viral RNA, 55.4% (95% CI: 0.418-0.669) of the patients with positive fecal RNA had persistent shedding of fecal RNA and pooled results from the other 4 studies including 848 discharged patients with nucleic acid-negative stool samples indicated that the occurrence of repositive stool swabs was 18.1% (95% CI: 0.028-0.335), that of repositive respiratory swabs was 22.8% (95% CI: 0.003-0.452), that of both repositive stool and respiratory swabs was 19.1% (95% CI: 0.019-0.363), and that of only repositive stool swabs was 9.6% (95% CI: 0.010-0.203). The digestive tract may be an important organ involved in COVID-19 infection and in the excretion of the virus. Because of the potential risk of fecal-oral transmission, giving emphasis on stool swab tests can help increase the detection rate of asymptomatic carriers and reduce missed diagnoses.

Efficacy and Safety of Endoscopic Submucosal Dissection for Rectal Tumors Extending Versus Not to the Dentate Line: A Systematic Review and Meta-Analysis.

GOALS: To evaluate the outcomes of endoscopic submucosal dissection (ESD) for rectal tumors extending to the dentate line (RTDLs) compared with rectal tumors not extending to the dentate line (non-RTDLs). BACKGROUND: There is limited composite data on the outcomes of ESD for RTDLs versus non-RTDLs. STUDY: We performed a systematic review and meta-analysis of studies that reported the clinical outcomes of ESD for RTDLs and non-RTDLs. Main outcomes were pooled estimated rates of en bloc/complete/curative resection, local recurrence, and incidence of bleeding, perforation, stricture, anal pain, and fever. RESULTS: Six studies were enrolled, including 265 cases of RTDLs and 788 cases of non-RTDLs. The en bloc resection rate was comparable for RTDLs and non-RTDLs [odds ratio (OR), 1.04; 95% confidence interval (CI), 0.55-1.95; P=0.90]. The complete resection rate was significantly lower for RTDLs (OR, 0.59; 95% CI, 0.41-0.83; P=0.003), as well as the curative resection rate (OR, 0.57; 95% CI, 0.38-0.87; P=0.010). The rates of stricture, postoperative anal pain and local recurrence were significantly higher for RTDLs than non-RTDLs (OR, 3.07; 95% CI, 1.01-9.31; P=0.05) (OR, 42.10; 95% CI, 4.73-374.97; P=0.0008) (OR, 3.00; 95% CI, 1.13-7.96; P=0.03), but the higher rates of postoperative bleeding and fever for RTDLs were not significantly (OR, 1.33; 95% CI, 0.53-3.30; P=0.54) (OR, 2.23; 95% CI, 0.55-9.07; P=0.26), as well as its lower perforation rate (OR, 0.85; 95% CI, 0.27-2.63; P=0.78). CONCLUSIONS: Despite its inferior outcomes than non-RTDLs, ESD is still a feasible and safe treatment for RTDLs if appropriate lesions are treated by experienced operators.

Effects of 5-aminosalicylates or thiopurines on the progression of low-grade dysplasia in patients with inflammatory bowel disease: a systematic review and meta-analysis.

PURPOSE: Although 5-aminosalicylates and thiopurines may have an antineoplastic effect on colorectal neoplasia in patients with inflammatory bowel disease (IBD), their impact on the progression of low-grade dysplasia (LGD) in IBD is uncertain. Therefore, we performed a systematic review and meta-analysis to evaluate whether 5-aminosalicylates or thiopurines can protect against the progression of LGD in patients with IBD. METHODS: Systematic searches of PubMed, EMBASE, Cochrane Library databases, and major conference proceedings were conducted to identify all eligible studies through March 2020. Data were pooled using a random effects model. Study quality was assessed using the Newcastle-Ottawa Scale. RESULTS: Five studies comprising 776 IBD patients with LGD were included. Overall, 5-aminosalicylates (Hazard ratio (HR) = 0.91, 95% confidence interval (CI) 0.55-1.51) and thiopurines (HR = 0.64, 95% CI 0.23-1.79) did not significantly reduce the risk of advanced colorectal neoplasia (high-grade dysplasia/cancer) in IBD patients with LGD. Moreover, the effects of 5-aminosalicylates or thiopurines on risk of advanced colorectal neoplasia in IBD patients with LGD were not significant by different primary sclerosing cholangitis status, study quality, sample size, and IBD type. CONCLUSIONS: In this study, we did not find a significant protective effect of 5-aminosalicylates or thiopurines on the progression of LGD in patients with IBD.

Hereditary angioedema: A rare cause of recurrent abdominal pain.

Hereditary angioedema is a rare autosomal dominant inherited disease which is characterized by an episodic, self-limiting increase in vascular permeability. Symptoms commonly involve in nonpitting, nonpruritic skin swellings. We present a case of hereditary angioedema. The patinets complained of a recurrent abdominal pain without accompanying skin swelling whose diagnosis was delayed nearly 20 years and accepted an unnecessary surgery. According to the decreased serum C1-inhibitor and C4 concentration, the patient was finally diagnosed with hereditary angioedema type I. After treatment with danazole, the patient reported a significant decrease in the frequency of attacks and the severity of pain. HAE is a rare cause of abdominal pain, however it needs to be taken as one of the differential diagnosis of various acute abdomens in order to avoid unnecessary surgeries.

CT-determined low skeletal muscle index predicts poor prognosis in patients with colorectal cancer.

BACKGROUND: Sarcopenia is highly prevalent among patients with colorectal cancer (CRC). Computed tomography (CT)-based assessment of low skeletal muscle index (SMI) is widely used for diagnosing sarcopenia. However, there are conflicting findings on the association between low SMI and overall survival (OS) in CRC patients. The objective of this study was to investigate whether CT-determined low SMI can serve as a valuable prognostic factor in CRC. METHODS: We collected data from patients with CRC who underwent radical surgery at our institution between June 2020 and November 2021. The SMI at the third lumbar vertebra was calculated using CT scans, and the cutoff values for defining low SMI were determined using receiver operating characteristic curves. Univariate and multivariate analyses were performed to assess the associations between clinical characteristics and postoperative major complications. RESULTS: A total of 464 patients were included in the study, 229 patients (46.7%) were classified as having low SMI. Patients with low SMI were older and had a lower body mass index (BMI), a higher neutrophil to lymphocyte ratio (NLR), and higher nutritional risk screening 2002 (NRS2002) scores compared to those with normal SMI. Furthermore, patients with sarcopenia had a higher rate of major complications (10.9% vs. 1.3%; p < 0.001) and longer length of stay (9.09 ± 4.86 days vs. 8.25 ± 3.12 days; p = 0.03). Low SMI and coronary heart disease were identified as independent risk factors for postoperative major complications. Moreover, CRC patients with low SMI had significantly worse OS. Furthermore, the combination of low SMI with older age or TNM stage II + III resulted in the worst OS in each subgroup analysis. CONCLUSIONS: CT-determined low SMI is associated with poor prognosis in patients with CRC, especially when combined with older age or advanced TNM stage.

Effect of adenovirus-mediated PTEN gene on ulcerative colitis-associated colorectal cancer.

PURPOSE: This study investigated the expression pattern of PTEN and its effect on carcinogenesis of ulcerative colitis-associated colorectal cancer, leading to insights into the underlying molecular mechanism. METHODS: We established a mouse model of ulcerative colitis-associated colorectal cancer by treating the animals with azoxymethane (AOM) and dextran sulphate sodium (DSS), and investigated the inflammation-dysplasia-carcinoma sequence. Expression patterns of PTEN, p-Akt and Ki-67 were shown by immunohistochemistry; western blotting techniques were used to detect protein expression of PTEN, p-Akt and caspase 3; TUNEL assay was used to measure apoptosis in colon epithelial cells; and colorimetric analysis was able to determine MPO activity in colon tissues. RESULTS: During the inflammation-dysplasia-carcinoma sequence, PTEN expression gradually decreased, while p-Akt expression increased; PTEN and p-Akt levels were negatively correlated. Compared to the AOM-DSS and Ad-0 groups, Ad-PTEN mice had longer colons, fewer tumours (P < 0.01) and smaller tumour sizes (P < 0.05). After injecting Ad-PTEN, expression of p-Akt, Ki-67 and MPO activity decreased dramatically, whereas PTEN increased. The TUNEL assay showed increased apoptotic cells and caspase 3 expression in the Ad-PTEN group. CONCLUSION: PTEN plays an important role in the inflammation-dysplasia-carcinoma sequence and may be a new molecular target in preventing and treating ulcerative colitis-associated colorectal cancer.

[Role of p38 mitogen-activated protein kinase pathway in pathogenesis of ulcerative colitis].

OBJECTIVE: To elucidate the role of p38 mitogen-activated protein kinase (p38MAPK) in the pathogenesis of ulcerative colitis (UC) and DSS-induced colitis in mice. METHODS: (1) 27 Balb/c mice were divided randomly into three groups: DSS-induced colitis group, normal control group and SB203580 treatment group. In DSS-induced colitis group, mice were feed with 5% DSS solution. In SB203580 treatment group, mice were feed with 5%DSS solution for 72 hours, then treated with intraperitoneal injection of SB203580 (1 mg/kg) once daily. Disease activity index (DAI) was record to evaluate the severity of colitis. The mice were executed after 7 days. The levels of TNF-alpha and IL-1beta were measured by ELISA. (2) A total of 54 cases were included in the study. 36 cases were patients with active ulcerative colitis, 18 cases were normal mucosa from 18 colon cancer cases served as control. Effects of SB203580 (a selective p38MAPK inhibitor) on expression of TNF-alpha and IL-1beta in intestinal mucosal biopsy specimens from patients with ulcerative colitis were determined on condition of tissue culture. RESULTS: (1) The DAI scores, the levels of TNF-alpha and IL-1beta in SB203580 group were lower significantly compared with DSS group (P < 0.05), and were increased significantly compared with normal control group (P < 0.05). (2) The levels of TNF-alpha and IL-1beta in intestinal mucosal biopsy specimens in SB203580 treatment group were lower significantly than those in UC group (P < 0.05). CONCLUSION: SB203580 can inhibit p38MAPK signal transduction pathway, then reduce the expression of pro-inflammatory cytokine TNF-alpha and IL-1beta.

RNA analysis of diet-induced sarcopenic obesity in rats.

Obesity has been suggested as a risk factor for sarcopenia. Sarcopenic obesity (SO), as a new category of obesity, is a high-risk geriatric syndrome in elderly individuals. However, knowledge about the molecular pathomechanisms of SO is still sparse. In the present study, starting at 13 months, male Sprague-Dawley (SD) rats were fed a high-fat diet (HFD) and normal diet (ND) for 28 weeks to establish a rodent animal model of SO with an identical protocol, which was further assessed and verified as a successful SO model. Through RNA-seq analysis of gastrocnemius muscle in SO rats, we found that differentially expressed genes (DEGs) and alternative splicing events (ASEs) focused mainly on inflammatory, immune-response, skeletal muscle cell differentiation, fat cell differentiation and antigen processing and presentation. Furthermore, as the core regulation factor of skeletal muscle, the mef2c (myocyte enhancer Factor 2C) gene also has a significant alternative 3' splice site (A3SS) and down-regulated expression in HFD-induced SO. The alternative genes targeted by mef2c identified by GO analysis were enriched in transcript regulation of RNA polymerase II promoter. In conclusion, these explorative findings in aging high-fat-fed rats might serve as a firm starting point for understanding the pathway and mechanism of sarcopenic obesity.

Diagnosis, prevalence, and outcomes of sarcopenia in kidney transplantation recipients: A systematic review and meta-analysis.

The prevalence of sarcopenia and its clinical predictors and clinical impact vary among kidney transplant recipients (KTRs), in part because of different diagnostic criteria. This study aimed to assess the reported diagnosis criteria of sarcopenia and compare them in terms of prevalence, clinical predictors, and impact of sarcopenia. The Medline, Embase, and Cochrane Library were searched for the full-length reports published until 28 January 2022. The subgroup analysis, meta-regression, and sensitivity analysis were performed and heterogeneity was assessed using the I2 . A total of 681 studies were retrieved, among which only 23 studies (including 2535 subjects, 59.7% men, mean age 49.8 years) were eventually included in the final analysis. The pooled prevalence in these included studies was 26% [95% confidence interval (95% CI): 20-34%, I2  = 93.45%], including 22% (95% CI: 14-32%, I2  = 88.76%) in men and 27% (95% CI: 14-41%, I2  = 90.56%) in women (P = 0.554 between subgroups). The prevalence of sarcopenia diagnosed using low muscle mass was 34% (95% CI: 21-48%, I2  = 95.28%), and the prevalence of using low muscle mass in combination with low muscle strength and/or low physical performance was 21% (95% CI: 15-28%, I2  = 90.37%) (P = 0.08 between subgroups). In meta-regression analyses, the mean age (regression coefficient: 1.001, 95% CI: 0.991-1.011) and percentage male (regression coefficient: 0.846, 95% CI: 0.367-1.950) could not predict the effect size. Lower body mass index (odds ratio (OR): 0.57, 95% CI: 0.39-0.84, I2  = 61.5%), female sex (OR: 0.31, 95% CI: 0.16-0.61, I2  = 0.0%), and higher age (OR: 1.08, 95% CI: 1.05-1.10, I2  = 10.1%) were significantly associated with a higher risk for sarcopenia in KTRs, but phase angle (OR: 0.81, 95% CI: 0.16-4.26, I2  = 84.5%) was not associated with sarcopenia in KTRs. Sarcopenia was not associated with rejections (risk ratio (RR): 0.67, 95% CI: 0.23-1.92, I2  = 12.1%), infections (RR: 1.03, 95% CI: 0.34-3.12, I2  = 87.4%), delayed graft functions (RR: 0.81, 95% CI: 0.46-1.43, I2  = 0.0%), and death (RR: 0.95, 95% CI: 0.32-2.82, I2  = 0.0%) in KRTs. Sarcopenia was found to be very common in KRTs. However, we have not found that sarcopenia had a negative impact on clinical health after kidney transplantation. Large study cohorts and multicentre longitudinal studies in the future are urgently needed to explore the prevalence and prognosis of sarcopenia in kidney transplant patients.

Efficacy and Safety of Endoscopic Submucosal Dissection for Dysplasia in Ulcerative Colitis Patients: A Systematic Review and Meta-Analysis.

BACKGROUND AND AIMS: Ulcerative colitis (UC) is associated with an increased risk of colorectal cancer. Current guidelines recommend endoscopic resection if the lesion is visible with distinct margins and a complete resection can be achieved. However, submucosal fibrosis due to chronic inflammation may increase the procedural risk and reduce the complete resection rate. The aim of this study is to assess the efficacy and safety of endoscopic submucosal dissection (ESD) for dysplasia in UC patients. MATERIALS AND METHODS: A systematic search of databases was performed until May 30, 2021. Studies that reported the resection rates and complication rates of ESD for dysplasia in UC patients were included. A random-effects model was used to generate conservative estimates of the prevalence of the outcome variables. All data analyses were performed using software Stata (version 15). RESULTS: 8 studies were enrolled in the meta-analysis, with a total of 203 dysplastic lesions in 192 UC patients. The mean lesion size was 26.7 mm. About 83% of the lesions were located in the left-side colon, and 90% of the lesions were nonpolypoid, and about 71% of the lesions had submucosal fibrosis. The mean procedural time of ESD was 83 minutes. The en bloc resection rate, complete resection rate, and curative resection rate were 94%, 84%, and 81%, respectively, with a local recurrence rate of 5%. The pooled prevalence of bleeding and perforation were 8% and 6%, respectively. The rates of metachronous tumors and additional surgery after ESD were 6% and 10%, respectively. CONCLUSION: Despite some limitations, our study suggests that ESD is an effective and safe treatment for dysplasia in UC patients. However, randomized controlled multicenter studies with less heterogeneity and longer follow-up are needed to better assess the clinical outcomes of ESD in UC patients.

PI3K/Akt signaling pathway is involved in the pathogenesis of ulcerative colitis.

OBJECTIVE: The purpose of this study was to investigate the role of the PI3K/Akt signaling pathway in the pathogenesis of ulcerative colitis (UC). MATERIALS AND METHODS: Mucosal biopsy specimens from 54 active UC cases and adjacent normal tissues from 18 colon cancer cases were investigated. Twenty-eight Balb/c mice were randomly divided into four groups. Dextran sulphate sodium (DSS) solution (5%) was used to develop the mouse colitis model. After treatment with wortmannin (a PI3K inhibitor), disease activity index (DAI) and histological score was determined for each group of mice. Expression of phosphorylated Akt (p-Akt) in UC patients and mouse intestinal mucosa was determined by immunohistochemical staining. We also determined the effect of wortmannin on tumor necrosis factor-α (TNF-α) expression in intestinal biopsy tissues of UC patients and mice with DSS-induced colitis. RESULTS: Wortmannin significantly reduced the level of p-Akt and TNF-α in the colitis tissues of UC patients and DSS-treated mice. Wortmannin significantly alleviated the inflammation of colitis as assessed by DAI and histological score in DSS-treated mice. CONCLUSION: The PI3K/Akt signal transduction pathway is involved in the regulation and release of pro-inflammatory cytokines such as TNF-α and plays an important role in the development and progression of UC.

Glial-derived neurotrophic factor regulates intestinal epithelial barrier function and inflammation and is therapeutic for murine colitis.

Although enteric glial cells (EGCs) have been demonstrated to play a key role in maintaining intestinal epithelial barrier integrity, it is not known how EGCs regulate this integrity. We therefore hypothesized that glial-derived neurotrophic factor (GDNF) produced by EGCs might be involved in this regulation. Here we investigated the role of GDNF in regulating epithelial barrier function in vivo. Recombinant adenoviral vectors encoding GDNF (Ad-GDNF) were administered intracolonically in experimental colitis induced by dextran sulphate sodium (DSS). The disease activity index (DAI) and histological score were measured. Epithelial permeability was assayed using Evans blue dye. The anti-apoptotic potency of GDNF in vivo was evaluated. The expression of tumour necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and myeloperoxidase (MPO) activity were measured by ELISA assay and/or RT-PCR. The expression of ZO-1, Akt, caspase-3, and NF-kappaB p65 was analysed by western blot assay. Our results showed that GDNF resulted in a significant reduction in enhanced permeability, inhibited MPO activity, IL-1beta and TNF-alpha expression, and increased ZO-1 and Akt expression. Moreover, GDNF strongly prevented apoptosis in vivo and significantly ameliorated experimental colitis. Our findings indicate that GDNF participates directly in restoring epithelial barrier function in vivo via reduction of increased epithelial permeability and inhibition of mucosal inflammatory response, and is efficacious in DSS-induced colitis. These findings support the notion that EGCs are able to regulate intestinal epithelial barrier integrity indirectly via their release of GDNF in vivo. GDNF is namely an important mediator of the cross-talk between EGCs and mucosal epithelial cells. GDNF may be a useful therapeutic approach to the treatment of inflammatory bowel disease.

Glial cell line-derived neurotrophic factor ameliorates dextran sulfate sodium-induced colitis in mice via a macrophage-mediated pathway.

Glial cell line-derived neurotrophic factor (GDNF) has been reported to protect mice from intestinal inflammation, but its anti-inflammatory mechanisms are poorly understood. Here we found that there was a downregulation in intestinal expression of GDNF accompanied by an increase of M1 macrophages in dextran sulfate sodium (DSS)-induced colitis in mice. GDNF treatment could facilitate the macrophages polarization towards the M2-like phenotype in DSS-treated mice and LPS-stimulated RAW264.7 cells, and reduce pro-inflammatory cytokines and increase anti-inflammatory cytokines. Mechanistically, the activation of PI3K/AKT pathway might contribute to the regulation of GDNF on macrophage phenotypes and inflammatory response. Moreover, the administration of GDNF significantly ameliorated colitis in DSS-treated mice, but this benefit of GDNF was diminished by macrophage depletion. Therefore, we propose a new mechanism whereby GDNF suppresses DSS-induced colitis in mice via a macrophage-mediated pathway.

The Role of E3 Ubiquitin Ligases and Deubiquitinases in Inflammatory Bowel Disease: Friend or Foe?

Inflammatory bowel disease (IBD), which include Crohn's disease (CD) and ulcerative colitis (UC), exhibits a complex multifactorial pathogenesis involving genetic susceptibility, imbalance of gut microbiota, mucosal immune disorder and environmental factors. Recent studies reported associations between ubiquitination and deubiquitination and the occurrence and development of inflammatory bowel disease. Ubiquitination modification, one of the most important types of post-translational modifications, is a multi-step enzymatic process involved in the regulation of various physiological processes of cells, including cell cycle progression, cell differentiation, apoptosis, and innate and adaptive immune responses. Alterations in ubiquitination and deubiquitination can lead to various diseases, including IBD. Here, we review the role of E3 ubiquitin ligases and deubiquitinases (DUBs) and their mediated ubiquitination and deubiquitination modifications in the pathogenesis of IBD. We highlight the importance of this type of posttranslational modification in the development of inflammation, and provide guidance for the future development of targeted therapeutics in IBD.

Targeting Gremlin 1 Prevents Intestinal Fibrosis Progression by Inhibiting the Fatty Acid Oxidation of Fibroblast Cells.

Intestinal fibrosis is a consequence of continuous inflammatory responses that negatively affect the quality of life of patients. By screening altered proteomic profiles of mouse fibrotic colon tissues, we identified that GREM1 was dramatically upregulated in comparison to that in normal tissues. Functional experiments revealed that GREM1 promoted the proliferation and activation of intestinal fibroblast cells by enhancing fatty acid oxidation. Blocking GREM1 prevented the progression of intestinal fibrosis in vivo. Mechanistic research revealed that GREM1 acted as a ligand for VEGFR2 and triggered downstream MAPK signaling. This facilitated the expression of FAO-related genes, consequently enhancing fatty acid oxidation. Taken together, our data indicated that targeting GREM1 could represent a promising therapeutic approach for the treatment of intestinal fibrosis.

Amelioration of dextran sulfate sodium-induced colitis by neuropeptide Y antisense oligodeoxynucleotide.

BACKGROUND: Neuropeptide Y (NPY) from enteric neurons has been shown to play an important role in immune and inflammatory responses. The purpose of the present study was to investigate the effects of NPY antisense oligodeoxynucleotides (ODNs) on an experimental model of ulcerative colitis (UC). METHODS: NPY antisense ODNs were administered in experimental colitis induced by dextran sulfate sodium (DSS). The disease activity index (DAI) and histological score were observed. The tumor necrosis factor (TNF)-alpha and NPY levels were measured by enzyme-linked immunosorbent assay. Phosphorylated Akt (p-Akt) expression was determined by immunohistochemical staining. Activated nuclear factor (NF)-kappaB was assessed by western blot analysis. Myeloperoxidase (MPO) activity was determined by using MPO assay kit. RESULTS: A significant improvement was observed in DAI and histological score in rats with NPY antisense ODNs, and the increase in NPY and TNF-alpha levels, MPO activity, and the expression p-Akt and p-NF-kappaB in rats with DSS-induced colitis was significantly reduced following the administration of NPY antisense ODNs. CONCLUSION: The administration of NPY antisense ODNs leads to an amelioration of DSS-induced colitis, suggesting that NPY plays an important role in modulating inflammation in colitis, and NPY antisense ODNs may be a useful therapeutic approach to the treatment of UC.

Opportunistic Infection in Hospitalised Patients with Inflammatory Bowel Disease.

OBJECTIVE: To investigate the incidence, clinical features, and risk factors of opportunistic infections in elderly patients with inflammatory bowel disease (IBD). STUDY DESIGN: Observational study. PLACE AND DURATION OF STUDY: Department of Digestive and Geriatrics Center, Sichuan University West China Hospital, China between January 2012 and January 2019. METHODOLOGY: Patients (≥18 years) with IBD were enrolled in this study. Clinical data from the infected elderly group (age ≥60 years), non-infected elderly group (age ≥60 years) and infected adult group (age: 18-59 years) were compared. Logistic regression analysis was used for risk factors associated with opportunistic infection. RESULTS:  A total of 8.9% (307/3,456) of patients with IBD had opportunistic infection. The opportunistic infection rate of elderly group was 16.5% (80/485), which was significantly higher than that of adult group (7.6%, 227/2,971, p <0.05). Compared with infected adult group or non-infected elderly group, infected elderly group had less fever and leukocytosis, but more hypoproteinemia and several activities (p <0.05). Cytomegalovirus and Epstein-Barr virus were the most common agents in elderly group and adult group, respectively. Multiple episodes (three or more) were more common in infected elderly group; the time of opportunistic infections was associated with systemic inflammatory reaction syndrome (SIRS, p <0.05). Logistic regression analysis showed that age ≥60 years, corticosteroids, immunosuppressive and biological agents were risk factors for opportunistic infections in patients with IBD. CONCLUSION: Hospitalised elderly IBD patients, receiving corticosteroids, immunosuppressive, and biological agents, are at higher risk for infection. The symptoms of opportunistic infections in elderly patients are atypical, but they are prone to multiple infections with poor prognosis. Key Words: Elderly patients, Inflammatory bowel disease, Opportunistic infection, Systemic inflammation reaction syndrome.

Clinical features of Epstein-Barr virus in the intestinal mucosa and blood of patients with inflammatory bowel disease.

BACKGROUND: The role of Epstein-Barr virus (EBV) in inflammatory bowel disease (IBD) remains to be elucidated. The aim of this study was to investigate the presence of EBV in the blood and intestinal mucosa of patients with IBD and evaluate the association between EBV positivity and IBD. METHODS: Patients with IBD, hospitalized between January 2015 and April 2018, were enrolled. The EBV-DNA load in blood samples from each subject was analyzed by quantitative real-time polymerase chain reaction. EBV-encoded small-RNA 1 (EBER-1) was detected by in-situ hybridization in intestinal mucosa tissue sections of patients with IBD. RESULT: EBV-DNA was detected in 48 out of 568 patients with IBD (8.4%), and EBER-1 positivity was detected in 27 of these patients (56.3%). Refractory IBD and severe mucosal inflammation were more common in patients with detectable levels of EBER-1 than in those without; the number of EBER-1-positive cells positively correlated with mucosal inflammation (P value < 0.05). Age (≥60 years old) and use of azathioprine were risk factors for EBV infection. There was no significant difference in clinical remission rate and surgical rate between the EBER-1 positive group and EBER-1 negative group, antiviral group and the non-antiviral group, among IBD patients who tested positive for EBV-DNA. CONCLUSION: Elderly patients with IBD, treated with azathioprine, are more susceptible to EBV positivity. Further, EBV mucosal detection correlated with the severity of mucosal damage and refractoriness, but not prognosis.

Glial-derived neurotrophic factor regulates enteric mast cells and ameliorates dextran sulfate sodium-induced experimental colitis.

BACKGROUND & AIMS: Although interactions between enteric glial cells (EGCs) and enteric mast cells have been demonstrated to play an important role in the pathogenesis of inflammatory bowel disease (IBD), the exact mechanisms by which EGCs regulate enteric mast cells are still unknown. The aims of this study were to investigate whether glial-derived neurotrophic factor (GDNF), which has been confirmed to be produced mostly by EGCs, might regulate enteric mast cells and ameliorate dextran sulfate sodium (DSS)-induced experimental colitis. METHODS: Recombinant adenoviral vectors encoding GDNF (Ad-GDNF) were administered intracolonically in experimental colitis induced by DSS. The disease activity index and histological score were measured. The expression of tumour necrosis factor-α (TNF-α), interleukin-6 and myeloperoxidase (MPO) activity were measured by ELISA assay. The expression of trypsin and ß-hexosaminidase were evaluated. GDNF specific receptor (GFR-α1/RET) was detected. The calcium reflux was tested by microplate reader. The expression p-JNK was analyzed by western blot assay. RESULTS: GDNF resulted in a significant inhibition of the activation of enteric mast cells by down-regulating JNK signal pathway, lessening intracellular calcium influx, and then reducing the degranulation as well as the expression of pro-inflammatory cytokines via combing with its receptor (GFR-α1/RET) in mast cells, and these inhibitory effects were abrogated by treatment with neutralizing antibody against GDNF. Moreover, the administration of GDNF led to an amelioration of experimental colitis. CONCLUSIONS: GDNF are able to regulate enteric mast cells and ameliorate experimental colitis. GDNF might be an important mediator of the cross-talk between EGCs and enteric mast cells, and GDNF might be a useful therapeutic drug for IBD.