Randomized controlled trial of pancreatic stenting to prevent pancreatitis after endoscopic retrograde cholangiopancreatography

AIM:To determine the effectiveness of pancreatic duct(PD) stent placement for the prevention of pancreatitis after endoscopic retrograde cholangiopancreatography(ERCP) in high risk patients.METHODS:Authors conducted a single-blind,randomized controlled trial to evaluate the effectiveness of a pancreatic spontaneous dislodgement stent against post-ERCP pancreatitis,including rates of spontaneous dislodgement and complications.Authors defined high risk patients as having any of the following:sphincter of Oddi dysfunction,difficult cannulation,prior history of post-ERCP pancreatitis,pre-cut sphincterotomy,pancreatic ductal biopsy,pancreatic sphincterotomy,intraductal ultrasonography,or a procedure time of more than 30 min.Patients were randomized to a stent group(n = 60) or to a non-stent group(n = 60).An abdominal radiograph was obtained daily to assessspontaneous stent dislodgement.Post-ERCP pancreatitis was diagnosed according to consensus criteria.RESULTS:The mean age(± standard deviation) was 67.4 ± 13.8 years and the male:female ratio was 68:52.In the stent group,the mean age was 66 ± 13 years and the male:female ratio was 33:27,and in the non-stent group,the mean age was 68 ± 14 years and the male:female ratio was 35:25.There were no significant differences between groups with respect to age,gender,final diagnosis,or type of endoscopic intervention.The frequency of post-ERCP pancreatitis in PD stent and non-stent groups was 1.7%(1/60) and 13.3%(8/60),respectively.The severity of pancreatitis was mild in all cases.The frequency of post-ERCP pancreatitis in the stent group was significantly lower than in the non-stent group(P = 0.032,Fisher's exact test).The rate of hyperamylasemia were 30%(18/60) and 38.3%(23 of 60) in the stent and non-stent groups,respectively(P = 0.05,χ2 test).The placement of a PD stent was successful in all 60 patients.The rate of spontaneous dislodgement by the third day was 96.7%(58/60),and the median(range) time to dislodgement was 2.1(2-3) d.The rates of stent migration,hemorrhage,perforation,infection(cholangitis or cholecystitis) or other complicationss were 0%(0/60),0%(0/60),0%(0/60),0%(0/60),0%(0/60),respectively,in the stent group.Univariate analysis revealed no significant differences in high risk factors between the two groups.The pancreatic spontaneous dislodgement stent safely prevented post-ERCP pancreatitis in high risk patients.CONCLUSION:Pancreatic stent placement is a safe and effective technique to prevent post-ERCP pancreatitis.Therefore authors recommend pancreatic stent placement after ERCP in high risk patients.     

The association between the incidence of urolithiasis and nutrition based on Japanese National Health and Nutrition Surveys

To clarify the association between regional variations in urolithiasis incidence and nutrition intake, we evaluated associated data from Japanese national surveys. The incidence of urolithiasis in 12 regions of Japan was calculated from 2005 patient data obtained from 430 hospitals (n = 92,797). Nutrition intake data were obtained from the National Health and Nutrition Survey. We examined the association between urolithiasis incidence and average intake of various types of food or nutrients by region. Continuing surveys in Japan reveal fixed variations in urolithiasis incidence among geographic regions. The national average of patients with urolithiasis was estimated as 203.1 per 100,000 citizens. Regarding food, intake of fruit correlated negatively with the incidence of urolithiasis (r = ?0.721, p = 0.008), while intake of eggs (r = 0.537, p = 0.072) and sugar (r = 0.475, p = 0.119) tended to positively correlate with incidence. Regarding nutrients, intake of potassium (r = ?0.500, p = 0.098), vitamin K (r = ?0.562, p = 0.057), and pantothenic acid (r = ?0.560, p = 0.058) tended to negatively correlate with incidence. The incidence of urolithiasis is higher in geographic areas with populations having low fruit and high sugar intake.     

Region-specific causal mechanism in the effects of ammonia on cerebral glucose metabolism in the rat brain

Ammonia, which is considered to be the main agent responsible for hepatic encephalopathy, inhibits oxidative glucose metabolism in the brain. However, the effects of ammonia on cerebral glucose metabolism in different brain regions remains unclear. To clarify this issue, we added ammonia directly to fresh rat brain slices and measured its effects on glucose metabolism. Dynamic positron autoradiography with [¹⁸F]2-fluoro-2-deoxy-d-glucose and 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium (WST-1) colorimetric assay revealed that ammonia significantly increased the cerebral glucose metabolic rate and depressed mitochondrial function, as compared to the unloaded control in each of the brain regions examined (cerebral cortex, striatum, and cerebellum), reflecting increased glycolysis that compensates for the decrease in aerobic metabolism. Pre-treatment with (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801), a N-methyl-d-aspartate (NMDA) receptor antagonist, significantly attenuated these changes induced by ammonia in cerebellum, but not in cerebral cortex or striatum. The addition of ammonia induced an increase in cyclic guanosine monophosphate (cGMP) levels in cerebellum, but not in cerebral cortex or striatum, reflecting the activation of the NMDA receptor-nitric oxide-cGMP pathway. These results suggested that NMDA receptor activation is responsible for the impairment of glucose metabolism induced by ammonia specifically in cerebellum.     

Effects of cicletanine on the urinary excretion of prostanoids and kallikrein,and on renal function in man

Summary The effects of cicletanine, a new antihypertensive agent, on the prostaglandin-kallikrein system and the reninangiotensin system were studied. A single oral dose of 200 mg cicletanine or placebo was administered to 9 healthy male volunteers, with samples of blood and urine obtained before and 2 hours after drug administration. Cicletanine increased the urine flow, urinary excretion of sodium, and fractional excretion of sodium by 47%, 115%, and 104%, respectively. While the excretion of 6-keto-prostaglandin-F₁ was enhanced significantly, urinary excretion of thromboxane-B₂, prostaglandin-E₂, and kallikrein were unchanged. Cicletanine also did not alter plasma renin activity, plasma aldosterone concentration, or creatinine clearance. These observations suggest that cicletanine may suppress sodium reabsorption at the nephron, and it may stimulate prostacyclin generation with no effect on that of thromboxane-A₂. Thus cicletanine may be beneficial in the management of cardiovascular disorders in which the equilibrium between prostacyclin and thromboxane is disturbed.