Systematic evaluation of the diagnostic approach of inflammatory bowel disease guidelines.

OBJECTIVE: To collect and evaluate the diagnostic approach of inflammatory bowel disease (IBD) guidelines and provide useful feedback for guideline developers and evidence-based clinical information to help physicians make decisions. METHODS: Diagnostic guidelines for IBD were retrieved by performing systemic and manual searches. Qualified clinical practice guidelines (CPGs) were included and then evaluated by four well-trained evaluators using the AGREE II instrument. To reduce the bias generated in this process, we used the Measurement Scale of Rate of Agreement (MSRA) tool to interpret the results. Guidelines with good recommendation distributions among the diagnostic field were further reclassified and evaluated. RESULTS: Fifteen diagnostic CPGs for IBD were identified and evaluated, and 70.3% (11/15) of the CPGs were above the recommended level. We observed heterogeneity among the diagnostic CPGs for IBD and discrepancies among different domains in one specific guideline. Potential improvements were identified in the fields of stakeholder involvement, rigour of development and applicability. By further analysing the heterogeneity of the recommendations and evidence in 5 UC-CPGs, we found the following issues: no discussion of diagnosing severe complications of UC, disputed significance of serologic and genetic diagnoses of UC, insufficient attention towards medical histories/physical examinations/differential diagnoses and discrepancy in classification criteria. CONCLUSION: The included diagnostic CPGs for IBD were generally of good quality, but heterogeneity was identified. Addressing these issues will provide useful feedback for the guideline updating process, and it will also benefit current clinical practice and eventually patient outcome.

Colorectal follicular lymphoma: A case report.

RATIONALE: Considering the low incidence of colorectal follicular lymphoma (FL) and its clinical features in endoscopic views, only a few studies have described the pathological diagnosis and treatment of this disease. This study aimed to reveal the overall process of clinical diagnosis and treatment of colorectal FL by conducting a case review. PATIENT CONCERNS: A 27-year-old female presented to our department because of "severe bloody stool" lasting for more than 1 month. Her primary symptom was melena. Colonoscopy revealed widespread flat polyps with various immunophenotypes (CD10+, BCL2+, BCL6+, cyclin D1-, CD5-) in the colorectal area. DIAGNOSIS: In accordance with manifestations on positron emission tomography-computed tomography (PET/CT), the patient was diagnosed with stage IV colorectal FL. INTERVENTIONS: PET/CT reexamination after 2 courses of rituximab, cyclophosphamide, liposomal doxorubicin, vincristine sulfate, and hydroprednisone (R-CHOP) regimen and 3 courses of R-CHOP plus etoposide regimen for chemotherapy indicated a significant reduction in tumor burden. Subsequently, rituximab was administered alone in 2 treatment courses. OUTCOMES: Lesions on PET/CT disappeared after reexamination. No recurrence was observed within the 12-month follow-up period. LESSONS: Colorectal FL is a rare disease with an inert clinical course and is common in the ileocecal area. Endoscopic views show multiple polyps. Interventional treatment is usually provided after observation of clinical symptoms or during disease progression. The disease has a relatively good prognosis.

Expression of annexin II in gastric carcinoma and its role in gastric cancer metastasis.

AIM: To investigate the expression of annexin II in gastric carcinoma and its role in the metastasis of gastric cancer. METHODS: The expression of annexin II in 51 cases of gastric carcinoma and 24 cases of adjacent tissues was detected by immunohistochemistry. The relationship between annexin II and clinical features of gastric cancer was analyzed. Annexin II specific siRNA was used to inhibit the expression of annexin II in gastric cancer HGC-27 cells, and the effects of annexin II on the migration and secretion of matrix metalloproteinases (MMPs) were observed. RESULTS: The positive rate of annexin II protein was 82.4% in gastric cancer tissues and 37.5% in adjacent tissues. There was significant difference between the two groups (P < 0.01); and the positive expression of annexin II was not related to the sex and age of the patients (P > 0.05). The expression of annexin II protein was correlated with tumor size, histological differentiation, TNM stage, Lymph node metastasis and other clinical features were significantly correlated, the difference was statistically significant (P < 0.05). Inhibition of annexin II expression, gastric cancer HGC-27 cells migration and secretion of MMPs were significantly decreased, the difference was statistically significant (P < 0.05). CONCLUSION: Annexin II is highly expressed in gastric cancer tissues, annexin II protein expression is related to tumor size, histological differentiation, TNM staging, lymph node metastasis and other clinical features were significantly correlated. Annexin II high expression can promote the invasion and metastasis of gastric cancer.

PPI versus Histamine H2 Receptor Antagonists for Prevention of Upper Gastrointestinal Injury Associated with Low-Dose Aspirin: Systematic Review and Meta-analysis.

This study compared proton pump inhibitors (PPIs) and histamine H2 receptor antagonists (H2RAs) for prevention of low-dose aspirin (LDA)-related gastrointestinal (GI) erosion, ulcer and bleeding. Electronic databases including PubMed, Embase, Cochrane Central Register of Controlled Trials, Chinese National Knowledge Infrastructure, Chinese Biomedical Literature Database, and WanFang Data were searched from the date of their establishment to December 31, 2013. Randomized controlled trials comparing PPIs and H2RAs for prevention of GI injury associated with low-dose aspirin (LDA) were collected. Two reviewers independently abstracted studies and patient characteristics and appraised study quality using the Cochrane risk-of-bias tool. Meta-analysis was performed using RevMan 5.1 software. We included nine RCTs involving 1047 patients. The meta-analysis showed that PPIs were superior to H2RAs for prevention of LDA-associated GI erosion/ulcer [odds ratio (OR=0.28, 95% confidence interval (CI): 0.16-0.50] and bleeding (OR=0.28, 95% CI: 0.14-0.59). In conclusion, PPIs were superior to H2RAs for prevention of LDA-related GI erosion/ulcer and bleeding. Higher quality, large, multicenter RCTs are needed to demonstrate the preventive effect of the two acid-suppressive drugs.

Proton pump inhibitors in prevention of low-dose aspirin-associated upper gastrointestinal injuries.

AIM: To determine the preventive effect and safety of proton pump inhibitors (PPIs) in low-dose aspirin (LDA)-associated gastrointestinal (GI) ulcers and bleeding. METHODS: We searched MEDLINE, EMBASE and the Cochrane Controlled Trials Register from inception to December 2013, and checked conference abstracts of randomized controlled trials (RCTs) on the effect of PPIs in reducing adverse GI events (hemorrhage, ulcer, perforation, or obstruction) in patients taking LDA. The preventive effects of PPIs were compared with the control group [taking placebo, a cytoprotective agent, or an H2 receptor antagonist (H2RA)] in LDA-associated upper GI injuries. The meta-analysis was performed using RevMan 5.1 software. RESULTS: We evaluated 8780 participants in 10 RCTs. The meta-analysis showed that PPIs decreased the risk of LDA-associated upper GI ulcers (OR = 0.16; 95%CI: 0.12-0.23) and bleeding (OR = 0.27; 95%CI: 0.16-0.43) compared with control. For patients treated with dual anti-platelet therapy of LDA and clopidogrel, PPIs were able to prevent the LDA-associated GI bleeding (OR = 0.36; 95%CI: 0.15-0.87) without increasing the risk of major adverse cardiovascular events (MACE) (OR = 1.00; 95%CI: 0.76-1.31). PPIs were superior to H2RA in prevention of LDA-associated GI ulcers (OR = 0.12; 95%CI: 0.02-0.65) and bleeding (OR = 0.32; 95%CI: 0.13-0.79). CONCLUSION: PPIs are effective in preventing LDA-associated upper GI ulcers and bleeding. Concomitant use of PPI, LDA and clopidogrel did not increase the risk of MACE.

Electrical stimulation therapy for slow transit constipation in children: a systematic review.

PURPOSE: Slow transit constipation is a common disorder in children, which often does not respond well to ordinary treatments. We have conducted a systematic review of reported studies in order to better define the current state of knowledge about electrical stimulation treatment of slow transit constipation in children. METHODS: We searched PubMed, Embase, Cochrane Library, BioMed Central, and ISI Web of Knowledge with relevant terms; six studies, all from one center, met the criteria for inclusion. Two trials were randomized clinical trials, and four were prospective studies. The number of subjects included in the studies was 8 to 39, with ages 3 to 18 years. RESULTS: Treatment sessions varied from 20 to 30 min 3 times per week to 1 h daily, and duration of therapy varied from 3 weeks to 6 months. Statistically significant improvements after electrical stimulation therapy were recorded in one to four outcome measures in each of the studies: frequency of defecation, soiling, Bristol Stool Scale, radionuclear transit studies, and quality of life; however, the improvements were of modest degree and of uncertain clinical significance. Quality assessment of the studies found various levels of bias, with attrition bias and reporting bias in all six. CONCLUSIONS: This systemic review found moderate support for the effectiveness of electrical stimulation therapy in slow transit constipation in children. However, better-designed studies, with larger and more diverse patient populations followed for longer time periods, will be needed in order to reliably determine the efficacy of electrical stimulation therapy in the treatment of this disorder.

The Relationship between Intestinal Motility and Interstitial Cells of Cajal in Nonalcoholic Fatty Liver Mice.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in western world. However, NAFLD shows an increasing trend in China every year, which has attracted the attention of national health authorities. The previous studies have shown that NAFLD caused severe gastrointestinal motor disorders, but little is known about the interstitial cells of Cajal (ICC) role in gastrointestinal motor disorders. OBJECTIVES: The aim of this study was to observe the ICC in jejunum of nonalcoholic fatty liver mice by immunohistochemistry and assessed the relationship between intestinal motility and ICC. MATERIALS AND METHODS: Thirty five Sprague-Dawley (SD) rats were randomly divided into nonalcoholic fatty liver (n = 25) and control groups (n = 10), rats were housed individually in cages and had free access to food and water, nonalcoholic fatty liver group was duplicated by high-fat diet (consisted of ordinary food, 20 g/kg cholesterol and 100 g/kg fat) feeding. Dextran blue-2000 was used to monitor the intestinal motility. The proximal small intestine was harvested to investigate the C-kit positive ICC. The hepatic tissue slices were used for pathological observation. RESULTS: Nonalcoholic fatty liver disease was successfully established. The intestinal motility in nonalcoholic fatty liver group (49.5 ± 10.9) was weaker compared to the control group (57.3 ± 8.9), P < 0.05. The rate of ICC also have shown statistically significant differences between nonalcoholic fatty liver (4.87 ± 2.97/mm (2)) and control groups (6.54 ± 3.13/mm (2)), P < 0.05. CONCLUSIONS: ICC may be related to the intestinal motility in nonalcoholic fatty liver mice.

Importance of b value in diffusion weighted imaging for the diagnosis of pancreatic cancer.

AIM: To investigate the use of multi-b-value diffusion-weighted imaging in diagnosing pancreatic cancer. METHODS: We retrospectively analyzed 33 cases of pancreatic cancer and 12 cases of benign pancreatic tumors at the Second Affiliated Hospital of Kunming Medical University from December 2008 to January 2011. The demographic characteristics, clinical presentation, routine magnetic resonance imaging and diffusion weighted imaging (DWI) features with different b values were reviewed. Continuous data were expressed as mean ± SD. Comparisons between pancreatic cancer and benign pancreatic tumors were performed using the Student's t test. A probability of P < 0.05 was considered statistically significant. RESULTS: Thirty-three patients with pancreatic cancer were identified. The mean age at diagnosis was 60 ± 5.6 years. The male: female ratio was 21:12. Twenty cases were confirmed by surgical resection and 13 by biopsy of metastases. T1 weighted images demonstrated a pancreatic head mass in 16 patients, a pancreatic body mass in 10 cases, and a pancreatic tail mass with pancreatic atrophy in 7 cases. Eight patients had hepatic metastases, 13 had invasion or envelopment of mesenteric vessels, 4 had bone metastases, and 8 had lymph node metastases. DWI demonstrated an irregular intense mass with unclear margins. Necrotic tissue demonstrated an uneven low signal. A b of 1100 s/mm² was associated with a high intensity signal with poor anatomical delineation. A b of 700 s/mm² was associated with apparent diffusion coefficients (ADCs) that were useful in distinguishing benign and malignant pancreatic tumors (P < 0.05). b values of 50, 350, 400, 450 and 1100 s/mm² were associated with ADCs that did not differentiate the two tumors. CONCLUSION: Low b value images demonstrated superior anatomical details when compared to high b value images. Tumor tissue definition was high and contrast with the surrounding tissues was good. DWI was useful in diagnosing pancreatic cancer.

Increased expression of DLX2 correlates with advanced stage of gastric adenocarcinoma.

AIM: To investigate the expression of distal-less homeobox 2 (DLX2) in gastric adenocarcinoma and its clinicopathological significance. METHODS: Gastric adenocarcinoma tissues were obtained from gastrectomy specimens of 129 patients from the Department of Surgery and Pathology, the Second Affiliated Hospital of Kunming Medical University. Sixty cases of normal gastric tissues were collected from gastrectomy specimens of adjacent gastric cancer margins greater than 5 cm. Patient diagnosis was established pathologically, and no patient had received chemotherapy or radiotherapy before surgery. All tissue specimens were formalin-fixed and paraffin-embedded. Immunohistochemistry was carried out to investigate the expression of DLX2 in 129 gastric adenocarcinoma tissues and 60 adjacent normal tissues. The immunostaining reaction was semiquantitatively evaluated based on the proportion of positive cells and the median staining intensity in normal gastric epithelial cells or tumor cells. All patients had follow-up records for more than 5 years. Correlations of DLX2 expression with clinicopathological features and prognosis of patients with gastric adenocarcinoma were analyzed. All statistical analyses were performed using the SPSS 17.0 software. RESULTS: The positive expression of DLX2 was detected in 68 (52.7%) cases of 129 gastric adenocarcinoma tissues and 14 (23.3%) cases of 60 adjacent normal tissues. The difference in DLX2 expression between gastric adenocarcinoma tissues and adjacent normal tissues was statistically significant (χ² = 14.391, P < 0.001). Moreover, high expression of DLX2 was detected in 48 (37.2%) cases of 129 human gastric cancer tissues, but not in adjacent normal tissues. The expression of DLX2 correlated with the size of tumor (P = 0.001), depth of invasion (P = 0.008), lymph node metastasis (P = 0.023) and tumor-node-metastasis stages (P = 0.020), but was not correlated with age, gender, histological differentiation and distant metastasis. The Kaplan-Meier survival analysis revealed that survival time of patients with high DLX2 expression was significantly shorter than that with low DLX2 expression. However, the multivariate analysis showed that invasion depth (P < 0.001), lymph nodes metastasis (P = 0.001) and distant metastasis (P < 0.001) were independent prognostic factors for patients with gastric adenocarcinoma, but DLX2 expression, tumor location and tumor size were not. CONCLUSION: These results suggest that increased expression of DLX2 may correlate with the advanced stage of gastric adenocarcinoma, and it may contribute to tumor development.

Ectopic expression of RASSF2 and its prognostic role for gastric adenocarcinoma patients.

RASSF2 has recently been identified as a potential tumor suppressor that serves as a Ras effector in various types of human cancers. However, there have been few reports detailing this in gastric cancer. Samples of gastric adenocarcinoma from 276 Chinese patients with follow-up were analyzed for RASSF2 protein expression by immunohistochemistry. RASSF2 was expressed in up to 31.2% (86/276) of this group of gastric carcinoma. The expression of RASSF2 was significantly lower in carcinomas than in normal mucosas (P<0.05). RASSF2 corresponded positively with patient age, histological differentiation, depth of tumor invasion, regional lymph node and distant metastasis, and TNM stage (all P<0.05). Further multivariate analysis revealed that patient gender, depth of tumor invasion, distant metastasis, TNM stage and the expression of RASSF2 were independent prognostic factors for patients with gastric cancer. The Kaplan-Meier plot showed that the overall mean survival time of the patients with RASSF2-negative expression was shorter than that of patients with positive expression (χ(2)=156.874, P<0.0001). Moreover, RASSF2-negative expression had a much more significant effect on the survival of those patients with early stage tumors (χ(2)=127.167, P<0.0001), highlighted by a >50.9% reduction in 3-year survival compared to that of patients with RASSF2-positive expression. In late stages, the difference was also significant (χ(2)=6.246, P=0.019), with a 35.5% reduction in 3-year survival. It is suggested that RASSF2 plays an important role in the evolution of gastric adenocarcinoma and should be considered as a potential marker for its prognosis.

Reduced Popdc3 expression correlates with high risk and poor survival in patients with gastric cancer.

AIM: To investigate the expression of Popeye domain containing 3 (Popdc3) and its correlation with clinicopathological features and prognosis of gastric cancer. METHODS: The method of immunohistochemistry was used to investigate the expression of Popdc3 in 306 cases of human gastric cancer and 84 noncancerous gastric tissues. Simultaneously, the relationship between Popdc3 expression and the survival of the patients was retrospectively analyzed. RESULTS: Popdc3 was detected in 72 (85.71%) of 84 human nontumor mucosa. High expression of Popdc3 protein was detected in 78 (25.49%) of 306 human gastric cancer cases, and low expression was detected in 228 (74.51%). Low expression of Popdc3 correlated with depth of invasion (P < 0.0001), regional lymph nodes (P < 0.0001) and distant metastasis (P = 0.02), and tumor, nodes, metastasis (TNM) stages (P < 0.0001). On multivariate analysis, only the patient's gender, regional lymph node metastasis, distant metastasis, TNM stages, and the expression of Popdc3 were independent prognostic factors in patients with gastric cancer. The Kaplan-Meier plot showed that low Popdc3 expression had a much more significant effect on the survival of those patients with early-stage tumors (χ² = 104.741, P < 0.0001), with a > 51.9% reduction in the three-year survival compared with high Popdc3 expression. In late stages, the difference was also significant (χ² = 5.930, P = 0.015), with a 32.6% reduction in the three-year survival. CONCLUSION: Reduced expression of Popdc3 may play a significant role in the carcinogenesis and progression of gastric cancer. Popdc3 may be an independent prognostic factor.

Abnormal expression of adhesion protein Bves is associated with gastric cancer progression and poor survival.

Although many molecular and biological studies have shown risk factors for gastric cancer, the available knowledge is still insufficient to unveil the exact mechanism of gastric cancer. To investigate the relationships between Bves expression and the clinicopathologic features of gastric cancer and whether Bves can act as prognostic indicators in gastric cancer. Tissues were obtained from the gastrectomy specimens of 306 human gastric cancer and 78 noncancerous gastric tissue at the Department of Surgery and Pathology, the Second Affiliated Hospital of Kunming Medical University from February 1996 to March 2007. The method of immunohistochemistry was used to investigate the expression of Bves in them. The relationship between Bves expression and the survival times of the patients was retrospectively analysed. Reduced expression of Bves frequently occurred in gastric cancer tissue. Low expression of Bves correlated with histologic differentiation, depth of invasion, regional lymph nodes and distant metastasis, and TNM stages (P < 0.05). Bves expression did not correlate with age, gender, location of tumor, size of tumor and histologic type (P > 0.05); Further multivariate analysis revealed that lymph node metastasis (P < 0.0001), distant metastasis (P < 0.0001), surgical treatment (P < 0.0001), and the expression of Bves (P < 0.0001) were independent prognostic factors in patients with gastric cancer; The Kaplan-Meier plot showed that survival times of patients with low Bves expression was significantly lower than those in patients with high Bves expression. Besides, low Bves expression had a much more significant effect on the survival of those patients with early stage tumors (χ2 = 131.216,P < 0.0001), highlighted by a >51.3% reduction in 3-year survival compared with that of patients with high Bves expression. In late stages, the difference was also significant (χ2 = 5.818,P = 0.016), with a 34.8% reduction in 3-year survival. Reduced expression of Bves in gastric cancer is associated with tumor progression and the patient's poor survival. This study showed that the studied protein has further provided a basis for the development of potential biomarker for gastric cancer prognosis.

[Down-regulation of vascular endothelial growth factor in human retinal pigment epithelial cells by small hairpin loop RNA targeting hypoxia inducible factor-1 alpha under hypoxia condition].

OBJECTIVE: To explore the effect of hypoxia inducible factor-1 alpha (HIF-1 alpha) gene on the expression of vascular endothelial growth factor (VEGF) in human retinal pigment epithelial (hRPE) cells under hypoxia conditions by using small hairpin loop RNA (shRNA) to silence HIF-1 alpha. METHODS: CoCl(2) (150 micromol/L) was used to simulate the hypoxia environment for hRPE cells. After choosing a target site of HIF-1 alpha mRNA, shRNA was designed and synthesized by this target site. hRPE cells were transfected by this shRNA in vitro. Then, these cells were cultured under hypoxia conditions (150 micromol/L CoCl(2)). The mRNA expression of HIF-1 alpha and VEGF was measured by semi-quantitative reverse transcription PCR (RT-PCR). The protein level of HIF-1 alpha and VEGF was studied by western blot analysis. RESULTS: After hRPE cells were transfected by HIF-1 alpha-specific shRNA, RT-PCR showed that the expression of HIF-1 alpha mRNA was inhibited by 77.1%, and western blot analysis showed that the level of HIF-1 alpha protein was significantly decreased in hRPE cells under hypoxia conditions. Moreover, the expression of VEGF mRNA was inhibited by 27.8% and the level of VEGF protein was also significantly decreased in transfected hRPE cells under hypoxia conditions. CONCLUSIONS: Under hypoxia conditions, HIF-1 alpha-specific shRNA effectively keeps HIF-1 alpha gene silenced, and consequently down-regulates VEGF expression against hypoxia. These results suggest that HIF-1 alpha is one of the most important cytokines for retinal neovascularization.

High-throughput production of prokaryotic membrane proteins.

Membrane proteins constitute ~30% of prokaryotic and eukaryotic genomes but comprise a small fraction of the entries in protein structural databases. A number of features of membrane proteins render them challenging targets for the structural biologist, among which the most important is the difficulty in obtaining sufficient quantities of purified protein. We are exploring procedures to express and purify large numbers of prokaryotic membrane proteins. A set of 280 membrane proteins from Escherichia coli and Thermotoga maritima, a thermophile, was cloned and tested for expression in Escherichia coli. Under a set of standard conditions, expression could be detected in the membrane fraction for approximately 30% of the cloned targets. About 22 of the highest expressing membrane proteins were purified, typically in just two chromatographic steps. There was a clear correlation between the number of predicted transmembrane domains in a given target and its propensity to express and purify. Accordingly, the vast majority of successfully expressed and purified proteins had six or fewer transmembrane domains. We did not observe any clear advantage to the use of thermophilic targets. Two of the purified membrane proteins formed crystals. By comparison with protein production efforts for soluble proteins, where approximately 70% of cloned targets express and approximately 25% can be readily purified for structural studies [Christendat et al. (2000) Nat. Struct. Biol., 7, 903], our results demonstrate that a similar approach will succeed for membrane proteins, albeit with an expected higher attrition rate.

Purification, reconstitution, and steady-state kinetics of the trans-membrane 17 beta-hydroxysteroid dehydrogenase 2.

Human membrane 17 beta-hydroxysteroid dehydrogenase 2 is an enzyme essential in the conversion of the highly active 17beta-hydroxysteroids into their inactive keto forms in a variety of tissues. 17 beta-hydroxysteroid dehydrogenase 2 with 6 consecutive histidines at its N terminus was expressed in Sf9 insect cells. This recombinant protein retained its biological activity and facilitated the enzyme purification and provided the most suitable form in our studies. Dodecyl-beta-D-maltoside was found to be the best detergent for the solubilization, purification, and reconstitution of this enzyme. The overexpressed integral membrane protein was purified with a high catalytic activity and a purity of more than 90% by nickel-chelated chromatography. For reconstitution, the purified protein was incorporated into dodecyl-beta-D-maltoside-destabilized liposomes prepared from l-alpha-phosphatidylcholine. The detergent was removed by adsorption onto polystyrene beads. The reconstituted enzyme had much higher stability and catalytic activity (2.6 micromol/min/mg of enzyme protein with estradiol) than the detergent-solubilized and purified protein (0.9 micromol/min/mg of enzyme protein with estradiol). The purified and reconstituted protein (with a 2-kDa His tag) was proved to be a homodimer, and its functional molecular mass was calculated to be 90.4 +/- 1.2 kDa based on glycerol gradient analytical ultracentrifugation and chemical cross-linking study. The kinetic studies demonstrated that 17 beta-hydroxysteroid dehydrogenase 2 was an NAD-preferring dehydrogenase with the K(m) of NAD being 110 +/- 10 microM and that of NADP 9600 +/- 100 microM using estradiol as substrate. The kinetic constants using estradiol, testosterone, dihydrotestosterone, and 20 alpha-dihydroprogesterone as substrates were also determined.