Application of Dynamic Contrast-Enhanced Ultrasound in Evaluation the Activity of Crohn's Disease.

BACKGROUND AND OBJECTIVE: The dynamic assessment of disease activity during the follow-up of patients with Crohn's disease (CD) remains a significant challenge. In this study, we aimed to identify the role of dynamic contrast-enhanced ultrasound (DCE-US) in the evaluation of activity of CD. METHODS: In the retrospective study, patients diagnosed with CD in our hospital were included. All the diagnoses were confirmed by clinical symptoms and ileocolonoscopical results. All patients underwent intestinal ultrasound and contrast-enhanced ultrasound (CEUS) examinations within 1 week of the ileocolonoscopy examinations. Acuson Sequoia (Siemens Healthineers, Mountain View, CA, USA) and Resona R9 Elite (Mindray Medical Systems, China) with curved array and Line array transducers were used. The CEUS examination was performed with SonoVue (Bracco SpA, Milan, Italy). DCE-US analysis was performed by UltraOffice (version: 0.3-2010, Mindray Medical Systems, China) software. Two regions of interest (ROIs) were set in the anterior section of the infected bowel wall and its surrounding normal bowel wall 2 cm distant from the inflamed area. Time-intensity curves (TICs) were generated and quantitative perfusion parameters were obtained after curve fittings. The Simple Endoscopic Score for Crohn's disease (SES-CD) was regarded as the reference standard to evaluate the activity of CD. The receiver operating characteristic curve (ROC) analyses were used to determine the diagnostic efficiency of DCE-US quantitative parameters. RESULTS: From March 2023 to November 2023, 52 CD patients were included. According to SES-CD score, all patients were divided into active group with the SES-CD score > 5 (n = 39) and inactive group SES-CD score < 5 (n = 13). Most of the active CD patients showed bowel wall thickness (BWT) > 4.2 mm (97.4%, 38/39) or mesenteric fat hypertrophy (MFH) on intestinal ultrasound (US) scan (69.2%, 27/39). Color Doppler signal of the bowel wall mostly showed spotty or short striped blood flow signal in active CD patients (56.4%, 22/39). According to CEUS enhancement patterns, most active CD patients showed a complete hyperenhancement of the entire intestinal wall (61.5%, 24/39). The TICs of active CD showed an earlier enhancement, higher peak intensity, and faster decline. Among all CEUS quantitative parameters, amplitude-derived parameters peak enhancement (PE), wash-in area under the curve (WiAUC), wash-in rate (WiR), wash-in perfusion index (WiPI), and wash-out rate (WoR) were significantly higher in active CD than in inactive CD (p < 0.05). The combined AUROC of intestinal ultrasound features and DCE-US quantitative perfusion parameters in the diagnosis of active CD was 0.987, with 97.4% sensitivity, 100% specificity, and 98.1% accuracy. CONCLUSIONS: DCE-US with quantitative perfusion parameters is a potential useful noninvasive imaging method to evaluate the activity of Crohn's disease.

Premorbid Steatohepatitis Increases the Seriousness of Dextran Sulfate Sodium-induced Ulcerative Colitis in Mice.

Background and Aims: The concurrence of nonalcoholic steatohepatitis (NASH) and ulcerative colitis (UC) is increasingly seen in clinical practice, but the underlying mechanisms remain unclear. This study aimed to develop a mouse model of the phenomenon by combining high-fat high-cholesterol diet (HFHCD)-induced NASH and dextran sulfate sodium (DSS)-induced UC, that would support mechanistic studies. Methods: Male C57BL/6 mice were randomly assigned to two groups receiving either a chow diet or HFHCD for 12 weeks of NASH modeling. The mice were the divided into four subgroups for UC modeling: (1) A control group given a chow diet with normal drinking water; (2) A colitis group given chow diet with 2% DSS in drinking water; (3) A steatohepatitis group given HFHCD with normal drinking water; and (4) A steatohepatitis + colitis group given HFHCD with 2% DSS in drinking water. Results: NASH plus UC had high mortality (58.3%). Neither NASH nor UC alone were fatal. Although DSS-induced colitis did not exacerbate histological liver injury in HFHCD-fed mice, premorbid NASH significantly increased UC-related gut injury compared with UC alone. It was characterized by a significantly shorter colon, more colonic congestion, and a higher histopathological score (p<0.05). Inflammatory (tumor necrosis factor-alpha, interleukin 1 beta, C-C motif chemokine ligand 2, and nuclear factor kappa B) and apoptotic (Bcl2, Bad, Bim, and Bax) signaling pathways were significantly altered in distal colon tissues collected from mice with steatohepatitis + colitis compared with the other experimental groups. Conclusions: Premorbid steatohepatitis significantly aggravated DSS-induced colitis and brought about a lethal phenotype. Potential links between NASH and UC pathogeneses can be investigated using this model.

Accelerated Infliximab Induction for Severe Lower Gastrointestinal Bleeding in a Young Patient with Crohn's Disease: A Case Report.

BACKGROUND: Severe lower gastrointestinal bleeding (SLGIB) is a rare complication of Crohn's disease (CD). The treatment of these patients is a clinical challenge. Monoclonal anti-TNFα antibody (IFX) can induce relatively fast mucosal healing. It has been reported for the treatment of SLGIB, but there are few reports on accelerated IFX induction in CD patients with SLGIB. CASE SUMMARY: A 16-year-old boy with a history of recurrent oral ulcers for nearly 1 year presented to the Gastroenterology Department of our hospital complaining of recurrent periumbilical pain for more than 1 mo and having bloody stool 4 times within 2 wk. Colonoscopy showed multiple areas of inflammation of the colon and a sigmoid colon ulcer with active bleeding. Hemostasis was immediately performed under endoscopy. The physical examination of the patient showed scattered small ulcers in the lower lip of the mouth and small cracks in the perianal area. Combined with his medical history, physical examination, laboratory examinations with high C-reactive protein (CRP), platelet count (PLT), erythrocyte sedimentation rate (ESR) and fecal calprotectin levels, imaging examinations and pathology, a diagnosis of CD was taken into consideration. According to the pediatric CD activity index 47.5, methylprednisolone (40 mg QD) was given intravenously. The abdominal pain disappeared, and CRP, PLT, and ESR levels decreased significantly after the treatment. Unfortunately, he had a large amount of bloody stool again after 1 wk of methylprednisolone treatment, and his hemoglobin level decreased quickly. Although infliximab (IFX) (5 mg/kg) was given as a combination therapy regimen, he still had bloody stool with his hemoglobin level decreasing from 112 g/L to 80 g/L in a short time, so-called SLGIB. With informed consent, accelerated IFX (5 mg/kg) induction was given 7 days after initial presentation. The bleeding then stopped. Eight weeks after the treatment, repeat colonoscopy showed mucosal healing; thus far, no recurrent bleeding has occurred, and the patient is symptom-free. CONCLUSION: This case highlights the importance of accelerated IFX induction in SLGIB secondary to CD, especially after steroid hormone treatment.

Expression and purification of functional HMGB1 A box by fusion with SUMO.

High­mobility­group­box chromosomal protein 1 (HMGB1) is a ubiquitous and abundant nuclear protein in eukaryotic cells. Nuclear HMGB1 serves an important role in maintaining nuclear stability under stress. However, extracellular HMGB1 exerts actions, which are distinctly different compared with these intracellular functions. HMGB1, when released extracellularly, is a potent innate signal, which initiates host defense mechanisms or tissue regeneration. HMGB1 has two DNA­binding domains: HMG A box and B box. The HMGB1 A box exhibits an antagonistic, anti­inflammatory effect, and is a potential therapeutic target, however, the large­scale expression and purification of the HMGB1 A box with high efficiency remains to be reported. In the present study, a SUMO­fusion expression system was used to express and purify high levels of functional HMGB1 A box to meet the requirements of therapeutic protein production.

Integrin antagonists are effective and safe for Crohn's disease: a meta-analysis.

AIM: To evaluate the efficacy and safety of integrin antagonists, including natalizumab and vedolizumab, in Crohn's disease (CD). METHODS: We carried out a literature search in PubMed, MEDLINE, EMBASE and the Cochrane Library to screen for citations from January 1990 to August 2014. Data analysis was performed using Review Manager version 5.2. RESULTS: A total of 1340 patients from five studies were involved in this meta-analysis. During 6-12 wk treatment, integrin antagonists increased the rate of clinical response and remission with OR = 1.69, 95%CI: 1.37-2.09 and 1.84, 95%CI: 1.44-2.34, respectively. No significant difference was found between integrin antagonists and placebo treatments regarding their adverse reactions (OR = 1.07, 95%CI: 0.83-1.38) and serious adverse reactions (OR = 0.81, 95%CI: 0.57-1.15). CONCLUSION: The results prove the efficacy and safety of integrin antagonists for CD treatment, although the treatment strategies varied.

ß-catenin is overexpressed in hepatic fibrosis and blockage of Wnt/ß-catenin signaling inhibits hepatic stellate cell activation.

ß-catenin, a core component of Wnt/ß-catenin signaling, has been shown to be an important regulator of cellular proliferation and differentiation. Abnormal activation of Wnt/ß-catenin signaling promotes tissue fibrogenesis. In the present study, the role of ß-catenin during liver fibrogenesis was analyzed and the functional effects of ß-catenin gene silencing in hepatic stellate cells (HSCs) using small interfering (si)RNA were investigated. The expression of ß-catenin in human hepatic fibrosis tissues of different grades and normal human hepatic tissues was examined using immunohistochemistry. To inhibit the Wnt/ß-catenin signaling pathway, siRNA for ß-catenin was developed and transiently transfected into HSC-T6 cells using Lipofectamine 2000. ß-catenin expression was evaluated by quantitative polymerase chain reaction (qPCR) and western blot analysis. The expression of collagen types Ⅰ and Ⅲ was evaluated by qPCR and immunofluorescent staining. Cellular proliferation and the cell cycle were analyzed using a methyl thiazolyl tetrazolium assay. Apoptosis was assessed by Annexin V staining. A higher expression level of ß-catenin was identified in the patients with high-grade hepatic fibrosis in comparison with that of the normal controls. Additionally, ß-catenin siRNA molecules were successfully transfected into HSCs and induced inhibition of ß-catenin expression in a time-dependent manner. ß-catenin siRNA treatment also inhibited synthesis of collagen types Ⅰ and Ⅲ in transfected HSCs. Furthermore, compared with those of the control group, siRNA-mediated knockdown of ß-catenin in HSC-T6 cells inhibited cell proliferation and resulted in cell apoptosis. This study suggests a significant functional role for ß-catenin in the development of liver fibrosis and demonstrates that downregulation of the Wnt/ß-catenin signaling pathway inhibits HSC activation. Thus, this study provides a novel strategy for the treatment of hepatic fibrosis.

Inhibition of high-mobility group box 1 expression by siRNA in rat hepatic stellate cells.

AIM: To explore the role of high-mobility group box 1 (HMGB1) protein during liver fibrogenesis and investigate the functional effects of HMGB1 gene silencing in hepatic stellate cells (HSCs) using siRNA. METHODS: Hepatic fibrosis in rats was induced throu-gh serial subcutaneous injections of dimethylnitrosamine, and expression of HMGB1 was detected by immunohistochemistry. HMGB1 siRNAs were developed and transiently transfected into HSC-T6 cells using Lipofectamine 2000. HMGB1 expression was evaluated by real-time polymerase chain reaction (PCR) and Western blotting analysis. Expression of α-smooth muscle actin (α-SMA) and collagen types I and III was evaluated by real-time PCR. Cell proliferation and the cell cycle were determined using the methyl thiazolyl tetrazolium method. Finally, collagen content in HSC supernatant was evaluated by an enzyme-linked immunosorbent assay. RESULTS: The results showed that HMGB1 was upregulated during liver fibrosis and that its expression was closely correlated with the deposition of collagen. siRNA molecules were successfully transfected into HSCs and induced inhibition of HMGB1 expression in a time-dependent manner. Moreover, HMGB1 siRNA treatment inhibited synthesis of α-SMA and collagen types I and III in transfected HSCs. CONCLUSION: This study suggests a significant fun-ctional role for HMGB1 in the development of liver fibrosis. It also demonstrates that downregulation of HMGB1 expression might be a potential strategy to treat liver fibrosis.