Value of Magnifying Chromoendoscopy and Magnifying Optical Enhancement Technology in Classifying Colorectal Polyps: A Prospective Controlled Study.

BACKGROUND AND AIMS: Magnifying chromoendoscopy (ME-CE) through the observation of pit patterns is a productive way to distinguish between neoplastic and nonneoplastic polyps. Magnifying optical enhancement technology (ME-OE) is an emerging virtual chromoendoscopy imaging technology and appeared to be a promising approach. However, this information is currently not available. This study is aimed at comparing the differential diagnostic value of ME-CE and OE for neoplastic and nonneoplastic polyps. Patients and Methods. Consecutive patients undergoing colonoscopy were randomized (1 : 1) into examination by ME-OE or ME-CE. Histopathological findings were utilized as the reference standard. Accuracy, sensitivity, specificity, and positive and negative predictive values of two endoscopy methods were compared using ME-OE (were classified according to the JNET classification) and ME-CE (were classified according to the Kudo pit pattern classification), respectively, and the time to predict the histological polyp type was compared. And the agreements between the pathological and clinical diagnosis by ME-OE or ME-CE were analyzed. RESULTS: A total of 365 polyps were found in the 220 patients included (ME-OE: 185; ME-CE: 180.202 had nonneoplastic polyps, 163 had neoplastic polyps). The diagnostic accuracy of ME-OE was higher than that of ME-CE (93% vs. 92%, p > 0.05). The average diagnosis time was lower in ME-OE than ME-CE (83 ± 26.4 s vs. 194 ± 17.7 s, p < 0.001). The agreements between the pathological and clinical diagnosis were at least substantial in both groups. CONCLUSION: ME-OE was superlative to ME-CE in predicting the histology of polyps. OE devoted classification would possibly similarly enhance the endoscopist performance. The trial is registered with ChiCT2000032075.

Comparison of white-light endoscopy, optical-enhanced and acetic-acid magnifying endoscopy for detecting gastric intestinal metaplasia: A randomized trial.

BACKGROUND: Gastric intestinal metaplasia (GIM) is a precancerous lesion of the stomach, which severely affects human life and health. Currently, a variety of endoscopic techniques are used to screen/evaluate GIM. Traditional white-light endoscopy (WLE) and acetic-acid chromoendoscopy combined with magnifying endoscopy (ME-AAC) are the interventions of choice due to their diagnostic efficacy for GIM. Optical-enhanced magnifying endoscopy (ME-OE) is a new virtual chromoendoscopy technique to identify GIM, which combines bandwidth-limited light and image enhancement processing technology to enhance the detection of mucosal and vascular details. We hypothesized that ME-OE is superior to WLE and ME-AAC in the evaluation of GIM. AIM: To directly compare the diagnostic value of WLE, ME-AAC, and ME-OE for detection of GIM. METHODS: A total of 156 patients were subjected to consecutive upper gastrointestinal endoscopy examinations using WLE, ME-AAC, and ME-OE. Histopathological findings were utilized as the reference standard. Accuracy, sensitivity, specificity, and positive and negative predictive values of the three endoscopy methods in the diagnosis of GIM were evaluated. Moreover, the time to diagnosis with ME-AAC and ME-OE was analyzed. Two experts and two non-experts evaluated the GIM images diagnosed using ME-OE, and diagnostic accuracy and intra- and inter-observer agreement were analyzed. RESULTS: GIM was detected in 68 of 156 patients (43.6%). The accuracy of ME-OE was highest (91.7%), followed by ME-AAC (86.5%), while that of WLE (51.9%) was lowest. Per-site analysis showed that the overall diagnostic accuracy of ME-OE was higher than that of ME-AAC (P = 0.011) and WLE (P < 0.001). The average diagnosis time was lower in ME-OE than in ME-AAC (64 ± 7 s vs 151 ± 30 s, P < 0.001). Finally, the inter-observer agreement was strong for both experts (k = 0.862) and non-experts (k = 0.800). The internal consistency was strong for experts (k = 0.713, k = 0.724) and moderate for non-experts (k = 0.667, k = 0.598). CONCLUSION: For endoscopists, especially experienced endoscopists, ME-OE is an efficient, convenient, and time-saving endoscopic technique that should be used for the diagnosis of GIM.

Characterizing the compositional variation of dissolved organic matter over hydrophobicity and polarity using fluorescence spectra combined with principal component analysis and two-dimensional correlation technique.

Dissolved organic matter (DOM) obtained from three leachates with different landfill ages was fractionated, and its compositional variation based on hydrophobicity and polarity was characterized by synchronous fluorescence spectra combined with principal component analysis (PCA) and two-dimensional correlation technique. The results showed that the bulk DOM and its fractions were comprised of tryosine-, tryptophan-, fulvic-, and humic-like substances. Tyrosine-like matter was dominant in the young leachate DOM and its fractions, while tryptophan-, fulvic-, and humic-like substances were the main components in the intermediate and old leachate DOMs and their fractions. Tryosine-, tryptophan-, fulvic-, and humic-like substances varied concurrently with the hydrophobicity and polarity. However, the change ratio of these substances was different for the three leachates. Tyrosine-like matter, humic-like materials, and fulvic-like substances were the most sensitive to the hydrophobicity and polarity in the young, intermediate, and old leachates, respectively. Such an integrated approach jointly enhances the characterization of the hydrophobicity- and polarity-dependent DOM fractions and provides a promising way to elucidate the environmental behaviors of different DOM species.

[Effluent carbon source improvement and sludge reduction by hydrolysis reactor with enhanced sludge utilization].

In order to strengthen the sludge hydrolysis and improve effluent carbon source, the structure of currently existing hydrolysis reactor was reformed. The new process combined separation of suspended solids in influent and hydrolysis of settled sludge. Experimental results show that the removal rate of SS was 81.4%, the average SS/BOD5 ratio of effluent was dropped to 0.4, far less than that of the influent ratios; SCOD/COD and COD(0.45-5)/COD ratio of the effluent increased by 35.4% and 17.7%, but the COD(> 100)/COD ratio reduced by 53.2%; BOD5/TN ratio increased from 3.7 to 4.7 and the BOD5/TP ratio from 23.8 to 36.4. The improvement of effluent carbon source was helpful for nitrogen and phosphorus removal in follow-up process. Meanwhile, the hydrolytic rate of sludge was up to 51.9%, realizing the reduction and resource-regeneration.

[Research of input water ratio's impact on the quality of effluent water from hydrolysis reactor].

Based on high SS/BOD and low C/N ratio of waste water of municipal wastewater treatment plant, the structure of currently existing hydrolysis reactor was reformed to improve the influent quality. In order to strengthen the sludge hydrolysis and improve effluent water quality, two layers water distributors were set up so that the sludge hydrolysis zone was formed between the two layers distribution. For the purpose of the hydrolysis reactor not only plays the role of the primary sedimentation tank but also improves the effluent water biodegradability, input water ratios of the upper and lower water distributor in the experiment were changed to get the best input water ratio to guide the large-scale application of this sort hydrolysis reactor. Results show, four kinds of input water ratio have varying degrees COD and SS removal efficiency, however, input water ratio for 1 : 1 can substantially increase SCOD/COD ratio and VFA concentration of effluent water compared with the other three input water ratios. To improve the effluent biodegradability, input water ratio for 1 : 1 was chosen for the best input water ratio. That was the ratio of flow of upper distributor was 50%, and the ratio of the lower one was 50%, at this case it can reduce the processing burden of COD and SS for follow-up treatment, but also improve the biodegradability of the effluent.