Development of an analytical method for multi-residue quantification of 18 anthelmintics in various animal-based food products using liquid chromatography-tandem mass spectrometry / 药物分析学报

In this study,we developed a simple screening procedure for the determination of 18 anthelmintics(including benzimidazoles,macrocyclic lactones,salicylanilides,substituted phenols,tetrahydropyr-imidines,and imidazothiazoles)in five animal-derived food matrices(chicken muscle,pork,beef,milk,and egg)using liquid chromatography-tandem mass spectrometry.Analytes were extracted using acetonitrile/1％acetic acid(milk and egg)and acetonitrile/1％acetic acid with 0.5 mL of distilled water(chicken muscle,pork,and beef),and purified using saturated n-hexane/acetonitrile.A reversed-phase analytical column and a mobile phase consisting of(A)10 mM ammonium formate in distilled water and(B)methanol were used to achieve optimal chromatographic separation.Matrix-matched standard calibration curves(R2≥0.9752)were obtained for concentration equivalent to ×1/2,×1,×2,×3,×4,and ×5 fold the maximum residue limit(MRL)stipulated by the Korean Ministry of Food and Drug Safety.Recoveries of 61.2-118.4％,with relative standard deviations(RSDs)of ≤19.9％(intraday and interday),were obtained for each sample at three spiking concentrations(×1/2,×1,and ×2 the MRL values).Limits of detection,limits of quantification,and matrix effects were 0.02-5.5 μg/kg,0.06-10 μg/kg,and-98.8 to 13.9％(at 20 μg/kg),respectively.In five samples of each food matrix(chicken muscle,pork,beef,milk,and egg)purchased from large retailers in Seoul that were tested,none of the target analytes were detected.It has therefore been shown that this protocol is adaptable,accurate,and precise for the quantification of anthelmintic residues in foods of animal origin.

The Effect of Autonomic Nerve System on Neurotensin Induced Motility in Isolated, Vascularly Perfused Rat Colon

BACKGROUND/AIMS: Although neurotensin (NT) stimulates colon motility and the passage of intestinal contents, the associated mechanism of action remains unclear. The objective of this study was to investigate the effects of NT on colon motility using isolated rat colon. METHODS: Intraluminal pressure was measured at both the proximal and distal portions of the isolated colon. An isolated rat colon was perfused with Krebs solution via the superior mesenteric artery. After stabilization, NT was administered in concentrations of 14, 28, 138 and 276 pM. After pretreatment with phentolamine, propranolol, hexamethonium, atropine or tetrodotoxin, NT was administered at a concentration of 276 pM, and then the intraluminal pressure was monitored. RESULTS: NT significantly increased colon motility at concentrations of 14, 28, 138, and 276 in the proximal colon (25.1+/-6.5%, 175.4+/-117.0%, 240.8+/-115.1% and 252.3+/-110.6%, respectively) and in the distal colon (35.6+/-11.8%, 97.5+/-35.1%, 132.7+/-36.7% and 212.1+/-75.2%, respectively). The stimulant effect of NT was more potent in the proximal colon, in a concentration-dependent manner (P<0.05). The stimulant effect of NT was significantly inhibited by atropine at both the proximal and distal colon and by tetrodotoxin at the proximal colon, but not by tetrodotoxin at the distal colon and not by propranolol, phentolamine, or hexamethonium at both the proximal and distal colon. CONCLUSIONS: NT increased colon motility at both the proximal and distal portions of the rat colon. The effects were more prominent at the proximal portion. The results of this study suggest that the stimulant action of NT may be mediated by local cholinergic muscarinic receptors.

Hypertriglyceridemia-induced Pancreatitis / 대한소화기학회지

Hypertriglyceridemia (HTG) is a rare cause of pancreatitis. However, the relationship between acute pancreatitis and severe HTG is well recognized. We report a case of necrotizing pancreatitis due to severe HTG (type IV) in a patient with poorly controlled diabetes. It was of particular interest that serum pancreatic enzymes were normal even though the imaging studies indicated the presence of necrotizing pancreatitis. Our case clearly demonstrates the various indices of HTG-induced necrotizing pancreatitis with a normal pancreatic enzyme level despite there being a serum triglyceride level < or=1,000 mg/dL. We present this case with a review of literature for hyperlipidemic pancreatitis in Korea.

Clinicopathologic Study of Colorectal Polyps and Obesity in Korean Adults / 대한소화기학회지

BACKGROUD/AIMS: Obesity is a rising problem in industrialized countries. Numerous epidemiologic studies have shown a positive association between obesity and colorectal polyps. There are few studies investigating the association between colorectal adenomatous polyps and body fat composition in Korea. We tried to examine the relationship between body fatness and colorectal adenomatous polyps in health check-up subjects in Korea. METHODS: Six thousand seven hundred and six routine health check-up subjects, who visited our hospital between March 2002 and April 2005 and underwent distal colon examimation with sigmoidoscopy, were enrolled in this study. Among them, colonoscopy was done in 860 patients to evaluate the entire colon. We tried to reveal the relationship between body mass index (BMI) and size, location, number and histopathological type of polyps. BMI was used as an indicator of obesity. RESULTS: The mean value of BMI in total polyp-free group (23.8+/-2.9) was not different from that of the polyp group (24.5+/-2.8, p=0.09). The frequency of rectosigmoid polyps in obese patients (20.4%) was higher than that in non-obese patients (16.0%, p or =4) correlated well with obesity. Moreover, age and triglyceride level in patients with colonic adenoma were significantly higher than in patients without colonic adenom. CONCLUSIONS: This study shows that obesity is not associated with colonic adenomatous polyp in Korean population. However, we observed that obesity may be associated with rectosigmoid colon polyps. Furthermore, age and triglyceride level might be the risk factors of colonic adenomatous polyps in Korean population.

Clinical Usefulness of Fecal Occult Blood Test as a Screening Method for Asymptomatic Patients with Colon Polyps / 대한소화기학회지

BACKGROUND/AIMS: Detection of asymptomatic benign colon polyp is increasing because colonoscopy is widely used as a screening and diagnostic method. Fecal occult blood test is usually performed for the selection of patients requiring colonoscopy as well as mass screening for colon cancer. The aim of this study was to investigate the usefulness of fecal occult blood test performed prior to colonoscopy as a screening method of benign colon polyps. METHODS: Clinical characteristics of patients with polyps were evaluated according to the fecal occult blood test results in patients who underwent one-day fecal occult blood test and colonoscopic polypectomies from May 2003 to October 2004, retrospectively. RESULTS: A total of 942 colonoscopic polypectomies in 288 patients were evaluated. Fecal occult blood tests were positive only in 32 patients (11.1%). In univariate analysis, there was a significant difference in polyp size (p=0.02) and location (p=0.03) according to the presence of positive fecal occult blood tests. In addition, age of the patient (p=0.046), polyp size (mean, p=0.04; largest, p<0.01) and the number of polyps (p=0.045) were significantly different. However, in multivariate analysis, only polyp size larger than 20 mm was significantly related with positive fecal occult blood test with estimated odds ratio of 4.71. CONCLUSIONS: Fecal occult blood test has limitations as a screening test in asymptomatic patients with colon polyps, except for colon polyps larger than 20 mm in size.

A Case of Gastric Syphilis Mimicking Advanced Gastric Cancer / 대한소화기내시경학회지

Gastric syphilis has been reported to be relatively rare due to the difficulty in making a histological diagnosis. However if a serologic test for syphilis is positive and the ulcer regresses after anti-syphilitic treatment, it can be assumed that the gastritis was caused by Treponema Pallidum. The clinical diagnosis of gastric syphilis ranges from a benign ulcer to mimicking an infiltrative carcinoma or lymphoma. We encountered a 21-year-old woman who was referred for linitis plastica with epigastric pain and weight loss. The gastroduodenoscopy revealed multiple irregular gastric mucopurulent shallow ulceration and several nodular lesions mimicking linitis plastica. The appropriate antibiotic treatment resulted in a dramatic improvement and a complete reversal of gastric lesions. This recent case of gastric syphilis emphasizes the importance of remaining alert to the manifestations of syphilis.

The Effect of Hemodialysis on Signal-Averaged Electrocardiography (SAECG) in Patients with End-Stage Renal Disease / 대한신장학회잡지

BACKGROUND: The presence of late potentials on the signal-averaged electrocardiography (SAECG) is predictive of ventricular tachycardia and sudden cardiac death. We investigated the acute effect of HD on the SAECG in patients with end-stage renal disease (ESRD). METHODS: Twenty HD patients with normal sinus rhythm on a routine ECG were enrolled. SAECGs were recorded immediately before, within 30 minute after, and then 24 hour after the completion of HD. Serum electrolyte, BUN, calcium, echocardiogram and body weight were examined before and after the HD. RESULTS: Positive late potentials on SAECG were detected in 8 patients (40%) before HD, 12 patients (60%) at 30 minute after HD, and 5 patients (25%) at 24 hour after HD. There was a significant change in QRSd (QRS duration) after HD: (110.3+-9.7 msec before HD; 112.3+-9.3 msec at 30 minute after HD; 109.5+-8.6 msec at 24 hour after HD) (p<0.05). The reduction of serum potassium was greater in positive late potential (n=12) than in negative late potential group after HD (n=8) (p<0.05). A significant negative correlation was seen between the changes of dialysis-induced serum total CO2 and QRSd changes (r=-0.534, p<0.05). CONCLUSION: SAECG parameters tended to be aggravated after HD in patient with ESRD. Prolongation of QRSd after HD could be explained by the changes of potassium and bicarbonate.

Sequential changes of magnetocardiogram in rat models of experimental myocardial infarction / 대한내과학회지

BACKGROUND: Magnetocardiogram (MCG), which records the changes of magnetic fields generated by the heart's electrical activity, theoritically can provide unique data for clinical application. To date, MCG has been investigated only at a single time point after myocardial infarction (MI) with severe left ventricular dysfunction in rats. The purpose of the present study was to investigate sequential changes of MCG after MI and to evaluate effects of infarct size on MCG. METHODS: Acute MI were induced by the permanent ligation of left coronary artery in 22 rats. Magnetic fields were recorded just above a rat with Nb Superconducting Quantum Interference Device (SQUID) gradiometer inside a magnetically shielded room. MCG was measured before and immediately after surgery and it was subsequently recorded at the time points of 1, 4 and 6 hours postoperatively. MCG was also measured at 1, 3, 7 and 21 days after surgery. RESULTS: Elevation of ST segment and appearance of pathological Q wave on the MCG were evident immediately after the ligation of coronary artery and persisted to 6 hours after MI. On MCG, ST segment was depressed and T wave was inverted from 1 day after MI. In rats with small- and moderate-sized MI (infarct size or = 30%). CONCLUSION: Evolutional changes of MCG were well-recognized up to 21 days after MI. Furthermore, the infarct size can be expressed by the extent of Q wave and ST segment depression on MCG. Taken together, these data indicate that MCG is a helpful modality for the diagnosis, evaluation of infarct size and follow up after MI.

MTHFR gene polymorphism as a risk factor for diabetic nephropathy and macrovascular disease in NIDDM patient / 대한내과학회지

BACKGROUND: Diabetic nephropathy develops in 20-30% of patients with non-insulin dependent diabetes mellitus (NIDDM). Poor glycemic control, hypertension and duration of diabetes are known as risk factors for the development of diabetic nephropathy and there is high prevalence of diabetic nephropathy in the patients who have familial history of diabetic nephropathy, so it has been assumed that genetic factor is associated with the background of its occurences. Recently it has been observed that a cytosine to thymidine substitution of the methylenetetrahydrofolate reductase (MTHFR) gene at nucleotide 677 (C677T) was related to diabetic nephropathy in patients with NIDDM and MTHFR gene polymorphism was also known to predispose to vascular disease. This study was performed to investigate whether MTHFR gene polymorphism is associated with the development of diabetic nephropathy and macrovascular disease in NIDDM patients. METHODS: The study population consisted of 243 NIDDM patients (duration> OR = 10 years). Nephropathy was defined by 24 hour urinary protein excretion of more than 500 mg. The MTHFR gene fragment was extracted using the polymerase chain reaction. The presence of the mutation was identified by HinfI digestion, which cuts at the mutation site, followed by 2.5% metaphore agarose electrophoresis and ethidium bromide staining. Statistical differences in genotype distribution and allele frequencies among the groups were assessed by the chi-square test. RESULTS: There was no difference in clinical characteristics except the prevalence of hypertension and diabetic retinopathy between nephropathy group and non-nephropathy group. The data do not show any difference of genotype distribution or allele frequencies between patients with or without diabetic nephropathy and macrovascular disease CONCLUSION: With the above results, it is assumed that there are no significant relationships among MTHFR gene polymorphism, diabetic nephropathy, and macrovascular disease.

A Case of Spontaneous Hemoperitoneum due to Gastroepiploic Vein Rupture in Alcoholic Cirrhosis / 대한간학회지

Portal hypertension often leads to the development of several collateral vessels that shunt blood flow from the portal to the systemic circulation. The rupture of intra-abdominal varix is an unusual complication of portal hypertension that can lead to life-threatening hemoperitoneum. If the patient is hemodynamically unstable due to massive intra-abdominal bleeding, exploratory laparotomy should be performed on the patient. There are several reported cases of intra-abdominal variceal bleeding such as paraumbilical varix, the varix from the small intestine and proximal colon etc. Spontaneous hemoperitoneum caused by the rupture of gastroepiploic vein varix, however, has not been reported in Korea, to the best of our knowledge. We will discuss a patient with portal hypertension due to liver cirrhosis who presented with acute intra-abdominal bleeding. During the laparotomy, he was found to have a rupture of the gastroepiploic vein. The vessel was ligated, and the patient recovered uneventfully by operative variceal ligation.

Electrogastrography in Uremic Patients on Maintenance Hemodialysis with Dyspepsia / 대한소화관운동학회지

BACKGROUND/AIMS: The changes in an Electrogastrography (EGG) in uremic patients on maintenance hemodialysis with dyspeptic complaints are not well known. The aim of this study was to investigate the EGG findings in uremic patients with dyspeptic complaints and note the difference of EGG findings between uremic patients with dyspeptic complaints and patients with functional dyspepsia. METHODS: Fifty two subjects were enrolled. They were assigned to: group I, healthy volunteers without dyspeptic complaints (n=15); group II, patients with dysmotility-like dyspepsia (n=22); or group III, uremic patients undergoing hemodialysis with dysmotility-like dyspepsia (n=15). The data was compared among groups. RESULTS: There was no difference in the percentage of normal slow wave frequency, and fed to fasting power ratio among the groups. However, frequencies of abnormal EGG findings were 4 (27%) in group I, 10 (40%) group II and 9 (60%) in group III. Therefore the frequency was marginally different among group I, group II or group III (p=0.06). CONCLUSIONS: Impaired gastric myoelectric activity was more frequently observed in uremic patients or patients with dysmotility-like dyspepsia than normal controls. However frequencies of abnormal EGG findings between uremic patients and patients with dysmotility-like dyspepsia were not significantly different.