Evaluation of optimal conditions for anionic surfactant removal in wastewater.

This study was conducted to find the optimal conditions for removing anionic surfactants in wastewater using the coagulant-flocculant method. Optimal conditions must be found to minimize the amount of metal materials that can cause secondary contamination and to improve performance. Five parameters were selected to investigate their influence on surfactant removal. The ranges of the independent variables were 0.5-5% for coagulant concentration, 0.1-1% for flocculant concentration, and 20-650 mg/L for surfactant concentration; the coagulant type was FeCl3·6H2O or Ca(OH)2; and the pH ranged from 2 to 10. The experimental results were analyzed with Minitab 19.1 to find the optimal conditions to maximize the removal rate of surfactant. In this study, a total of 20 experiments were carried out using a half fractional factorial design (FFD) including two center points with a resolution of 5 and a pseudo-center point. The results demonstrated that coagulant concentration, flocculant concentration, and pH were significant independent variables with respect to surfactant removal. The fitted regression equation confirmed that the surfactant removal rate was maximized when the coagulant concentration was 5%, the flocculant concentration was 0.1%, and the pH was 10.

Functionalized cellulose to remove surfactants from cosmetic products in wastewater.

A flocculant composed of paper mulberry dicarboxylic cellulose (PM-DCC) made from using paper mulberry (Broussonetia kazinoki Siebold and Zucc.) has been developed to reduce the amount of inorganic coagulants needed to remove surfactants in wastewater. The characteristics of PM and soda pulp were determined according to the degree of polymerization, α-cellulose, lignin, free sugar, and extract contents. FTIR, XRD, the aldehyde content, the carboxyl content and coagulant-flocculation experiments were conducted to confirm the properties of PM-DCC and paper mulberry dialdehyde cellulose (PM-DAC). A dramatic removal efficiency (95.62 %) was revealed when 0.3 % PM-DCC was added into a linear alkylbenzene sulfonate (LAS) solution with 1% FeCl3·6H2O at pH 2. This means that PM-DCC contributes to both a lower amount of inorganic coagulant needed and a reduction of water pollution by an ecofriendly method.

Clinical Response of Rifaximin Treatment in Patients with Abdominal Bloating.

BACKGROUND/AIMS: Abdominal bloating is a troublesome complaint due to insufficient understanding of the pathophysiology. The aim of this study was to evaluate the efficacy of rifaximin in reducing bloating associated with functional gastrointestinal disorders (FGIDs). METHODS: A total of 63 patients were treated with rifaximin for FGIDs with bloating or gas-related symptoms between 2007 and 2013 at Seoul National University Bundang Hospital. Rifaximin was administered at a dose between 800 mg/day and 1,200 mg/day for 5 to 14 days. The proportion of patients who had adequate relief of global FGID symptoms and FGID-related bloating was retrospectively assessed. The response was recorded when the symptoms were reduced by at least 50% at the follow-up after treatment cessation. RESULTS: The mean age was 56.8±14.2 years; 49.2% were females. According to Rome III criteria, 20.6% (13/63) had irritable bowel syndrome (IBS) with constipation, 9.5% (6/63) had IBS with diarrhea, 4.8% (3/63) had mixed IBS, 23.8% (15/63) had functional dyspepsia, and 12.7% (8/63) had functional bloating. Of the 51 subjects who were followed-up, 30 (58.8%) had adequate relief of global FGID symptoms and 26 (51.0%) experienced improvement of abdominal bloating after rifaximin treatment. The proportion of female was slightly higher in non-response group than in the response group (60.0% vs. 34.6%, p=0.069). Otherwise, there was no difference between the two groups. CONCLUSIONS: Despite the limitations of this retrospective study, our data confirms that rifaximin may be beneficial for abdominal bloating. Further prospective clinical trial with a larger cohort is needed.

Characteristics of cytomegalovirus enterocolitis in patients with or without inflammatory bowel diseases.

OBJECTIVES: Cytomegalovirus (CMV) disease is more common in immunocompromised patients but may occur in people with normal immune function. In addition, CMV enterocolitis can aggravate inflammatory bowel diseases (IBD), but there was little knowledge of differences in clinical and endoscopic features of CMV enterocolitis between patients with IBD and without IBD. The aim of this study was to determine the difference in clinical implication in CMV enterocolitis between the IBD patients and non-IBD patients. METHODS: This was a retrospective study of 82 patients with CMV enterocolitis based on the pathologic findings at two tertiary referral hospitals from 2003 to 2013. Clinical and endoscopic characteristics and clinical course were analyzed according to the presence of IBD. RESULTS: Of the 82 patients, 25 (30.5%) had IBD and 57 (69.5%) did not have IBD. Hematochezia was more common in IBD patients (84.0% vs. 35.1%; p = .001), but fever and positive CMV antigenemia were more common in non-IBD patients (50.9% vs. 12.0%; p = .001; 54.4% vs. 28.0; p = .027). Endoscopic findings showed more ulcer with inflammation in IBD patients (68.0% vs. 35.2%; p = .005). Sixty-four patients were treated with antiviral agents and 12 patients who did not receive antiviral agents recovered spontaneously. All naturally healed patients were in normal immune status. CONCLUSIONS: Hematochezia is more common in IBD patients and fever/CMV antigenemia is more common in patients without IBD. In patients without IBD, the natural resolution of CMV enterocolitis is expected at least in normal immune function.

Green tea extracts for the prevention of metachronous colorectal polyps among patients who underwent endoscopic removal of colorectal adenomas: A randomized clinical trial.

OBJECTIVES: To determine the preventive effect of green tea extract (GTE) supplements on metachronous colorectal adenoma and cancer in the Korean population. MATERIALS AND METHODS: One hundred seventy-six subjects (88 per each group) who had undergone complete removal of colorectal adenomas by endoscopic polypectomy were enrolled. They were randomized into 2 groups: supplementation group (0.9 g GTE per day for 12 months) or control group without GTE supplementation. The 72-h recall method was used to collect data on food items consumed by participants at baseline and the 1-year follow-up during the past 48 h. Follow-up colonoscopy was conducted 12 months later in 143 patients (71 in control group and 72 in the GTE group). RESULTS: Of the 143 patients completed in the study, the incidences of metachronous adenomas at the end-point colonoscopy were 42.3% (30 of 71) in control group and 23.6% (17 of 72) in GTE group (relative risk [RR], 0.56; 95% confidence interval [CI], 0.34-0.92). The number of relapsed adenoma was also decreased in the GTE group than in the control group (0.7 ± 1.1 vs. 0.3 ± 0.6, p = 0.010). However, there were no significant differences between the 2 groups in terms of body mass index, dietary intakes, serum lipid profiles, fasting serum glucose, and serum C-reactive protein levels (all p > 0.05). CONCLUSION: This study of GTE supplement suggests a favorable outcome for the chemoprevention of metachronous colorectal adenomas in Korean patients (ClinicalTrials.gov number, NCT02321969).

A comparison of endoscopic treatments in rectal carcinoid tumors.

BACKGROUND: Various endoscopic techniques for rectal carcinoid tumors have been developed recently. In this study, we compared the outcomes of conventional endoscopic mucosal resection (EMR), strip biopsy, and EMR after circumferential precutting (EMR-P). METHODS: From March 2004 to July 2014, the medical records of 188 patients (190 rectal carcinoid tumors) who were treated with an endoscopic procedure for rectal carcinoid tumors were investigated retrospectively. The characteristics of the patients and tumors, the selection of the treatment method, the rate of complete resection, and the rate of complications were analyzed retrospectively. RESULTS: Forty-seven, 75 and 68 cases of EMR, strip biopsy and EMR-P were performed, respectively. The mean procedure time was not significantly different between the EMR, strip biopsy and EMR-P cases (5.6, 6.5 and 7.4 min, respectively, P = 0.119). En bloc resection was achieved in most of the cases (97.8, 98.7 and 95.5 % in the EMR, strip biopsy and EMR-P cases, respectively). However, histologic examination showed positive lateral or deep resection margins in 57 out of 190 cases (30.0 %). Multivariate analysis showed that the strip biopsy and EMR-P methods were independent factors for pathologic complete resection (negative in both lateral and deep resection margins), with odds ratios for margin involvement of 0.20 and 0.43 with 95 % confidence intervals from 0.08 to 0.47 and 0.19 to 0.96, respectively. In all the follow-up cases (81 of 190, 42.6 %), no local recurrence or distal metastasis was found. CONCLUSIONS: Compared to conventional EMR, strip biopsy and EMR-P had a lower risk of incomplete resection. The procedure time and complication rate did not differ between the three groups, and no recurrence was detected during the follow-up period. Strip biopsy and EMR-P are safe and effective methods for the treatment of rectal carcinoid tumors.

Correlation between hypersensitivity induced by esophageal acid infusion and the baseline impedance level in patients with suspected gastroesophageal reflux.

OBJECTIVES: To evaluate the relevance between the pH parameters and baseline impedance level or esophageal hypomotility in patients with suspected gastroesophageal reflux. METHOD: The recordings of 51 patients with heartburn, acid regurgitation, globus or noncardiac chest pain were analyzed. Evaluation included a 24-h multichannel intraluminal impedance-pH test while on off-proton pump inhibitor therapy over 1 week, high-resolution manometry and Bernstein test. Mean baseline impedance level at the most distal portion of the impedance channel was assessed manually. Esophageal hypomotility was evaluated using transitional zone defect (TZD) and distal break (DB) length measurement. RESULT: In the study subjects (n = 51), 6 had a DeMeester score of more than 14.7 and 14 had a positive symptom index. The Bernstein test was positive in ten patients. The baseline impedance level was inversely correlated with the acid exposure time % (r = -0.660, P < 0.001). Also, all reflux and weakly acid reflux time % measured by impedance monitoring showed a weak correlation with TZD + DB length (r = 0.327 and 0.324, P = 0.019 and 0.020, respectively). Although a positive Bernstein test has no relevance for the acid exposure time or acid-related symptoms as represented by the DeMeester score or symptom index, the baseline impedance level was significantly lower in patients with a positive Bernstein test than in those with a negative one (2,628.4 ± 862.7 vs. 1,752.2 ± 611.1 Ω, P = 0.004). CONCLUSION: A lower baseline impedance level is closely related to increased esophageal acid exposure. Hypersensitivity induced by esophageal acid infusion might be attributed to acid-induced mucosal changes of the esophagus.

Abdominal bloating: pathophysiology and treatment.

Abdominal bloating is a very common and troublesome symptom of all ages, but it has not been fully understood to date. Bloating is usually associated with functional gastrointestinal disorders or organic diseases, but it may also appear alone. The pathophysiology of bloating remains ambiguous, although some evidences support the potential mechanisms, including gut hypersensitivity, impaired gas handling, altered gut microbiota, and abnormal abdominal-phrenic reflexes. Owing to the insufficient understanding of these mechanisms, the available therapeutic options are limited. However, medical treatment with some prokinetics, rifaximin, lubiprostone and linaclotide could be considered in the treatment of bloating. In addition, dietary intervention is important in relieving symptom in patients with bloating.

Clinical characteristics and treatment outcomes of 3 subtypes of achalasia according to the chicago classification in a tertiary institute in Korea.

BACKGROUND/AIMS: Achalasia is classified into 3 types according to the Chicago classification. The aim of this study was to investigate characteristics and treatment outcomes of 3 achalasia subtypes in Korean patients. METHODS: Fifty-five patients diagnosed with achalasia based on conventional or high-resolution esophageal manometry were consecutively enrolled. Their clinical characteristics, manometric, endoscopic and esophagographic findings and treatment responses were analyzed among the 3 subtypes of achalasia. RESULTS: Of 55 patients, 21 (38.2%) patients had type I, 28 (50.9%) patients had type II and 6 (10.9%) patients had type III. The median follow-up period was 22.4 (interquartile range, 3.6-67.4) months. Type III patients were older than type I and II patients (70.0 vs. 46.2 and 47.6 years, P = 0.023). The width of the esophagus in type I patients was wider with more frequent bird's beak appearance on esophagogram than the other 2 types (P = 0.010 and 0.006, respectively). Of the 50 patients who received the evaluation for treatment response at 3 months, 7 patients (36.8% vs. 26.9%) were treated with pneumatic dilatation and 4 patients (21.1% vs. 15.4%) with laparoscopic Heller's myotomy in type I and II groups, respectively. The treatment responses of pneumatic dilatation and Heller's myotomy in type I group were 71.4 and 50.0% and in type II were 85.7 and 75.0%, respectively, and all 5 patients in type III group showed good response to medical therapy. CONCLUSIONS: Clinical characteristics of 3 achalasia subtypes in Korean patients are consistent with other studies. Treatment outcomes are variable among 3 subtypes.

Risk factors of atrophic gastritis and intestinal metaplasia in first-degree relatives of gastric cancer patients compared with age-sex matched controls.

BACKGROUND: To identify whether first-degree relatives (FDRs) of gastric cancer (GC) patients have increased risk for atrophic gastritis (AG) and intestinal metaplasia (IM) in relation to other risk factors of GC. METHODS: The study cohort consisted of 224 pairs of age-sex matched controls and FDRs. AG and IM in the gastric mucosa were scored histologically using the updated Sydney classification. Risk of having AG and IM was studied by comparing FDRs to controls. Impacts of age, H. pylori infection, smoking, dietary and socioeconomic factors on the presence of AG and IM were studied. RESULTS: In multivariate regression analysis, FDRs had adjusted OR of 2.69 (95% CI 1.06-6.80, P=0.037) for antral IM in male population. Adjusted OR for antral AG and IM were 9.28 (95% CI 4.73-18.18, P<0.001) and 7.81 (95% CI 3.72-16.40, P<0.001) for the H. pylori infected subjects in total population. Getting old by 5 years increased the ORs of having AG and IM by approximately 1.25 fold (P<0.001). Spicy food increased the OR of antral IM by 2.28 fold (95% CI 1.36-3.84, P=0.002). CONCLUSIONS: Family history of GC was an independent risk factor for antral IM in male in our study, which could be one reason for the increase of gastric cancer in the family member of gastric cancer. It could be an evidence for the necessity of frequent endoscopy in the presence of family history of GC compared to general population in male.