Dopamine-induced migrating myoelectrical complex-like activity in human duodenum

The effect of dopamine on human gastric and small intestinal interdigestive motility was investigated in 12 subjects. Intestinal motility was recorded by means of a four-lumen polyvinyl probe with four open tips located 15 cm apart, continuously perfused with distilled water. In each subject during the same study, after recording two consecutive spontaneous phase III of migrating myoelectrical complexes and when a phase II appeared, dopamine was infused intravenously twice in a dose of 5 g/kg/min for 15 min with an interval of 20 min between each infusion. In six subjects, the second dopamine infusion was preceded by a treatment with sulpiride (10 mg, intravenously, as bolus) or domperidone (10 mg, intravenously, as bolus), each considered a highly selective dopamine antagonist. The results show that dopamine stimulates duodenal motility producing a pattern similar to that observed in phase III of spontaneously occurring migrating myoelectrical complexes. The second dopamine infusion reproduced in all cases the same pattern of motility as observed during the first infusion. Sulpiride and domperidone prevented the effect of dopamine in all cases. It is therefore suggested that dopamine-induced duodenal motility may involve specific dopaminergic receptors.     

Rifaximin in patients with lactose intolerance

BACKGROUND: Abdominal symptoms linked to lactose malabsorption may be caused by metabolic activity of colonic bacteria. Rifaximin, a non-absorbable rifampycin derivative, is active against colonic bacteria, it may be useful in the treatment of lactose intolerance. AIM: The aim of this study has been to evaluate short-term rifaximin therapy in patients with lactose intolerance. METHODS: Thirty-two patients with lactose intolerance diagnosed using the hydrogen lactose breath test were studied. Fourteen patients received rifaximin 800 mg/day for 10 days, 13 patients followed a diet without milk for 40 days and 5 patients received a placebo for 10 days. Total breath H(2) excretion expressed as area under the curve, and the symptom score were evaluated in all patients at the start, and subsequently after 10 and 40 days. RESULTS: In the 14 patients who received rifaximin for 10 days, area under the curve at day 10 and day 40 was statistically significantly lower than the one computed at basal (P<0.01). Diet reduced area under the curve progressively reaching statistical significance at day 40, while the placebo did not change area under the curve throughout the study. The total symptom score significantly improved after rifaximin and diet. CONCLUSION: In patients with lactose intolerance, a 10-day therapy with rifaximin as well as 40-day diet without lactose reduces the area under the curve and the symptom score.     

Enhanced release of atrial natriuretic factor during exercise-induced myocardial ischaemia in patients after acute myocardial infarction.

To determine whether acute myocardial ischaemia induced by dynamic exercise can lead to changes in plasma levels of atrial natriuretic factor, we performed symptom-limited bicycle electrocardiographic tests in 20 males with recent acute myocardial infarction and in 8 control males. Ten patients developed exercise-induced myocardial ischaemia and 10 patients did not. There were no significant differences between the two groups with regard to age, site of myocardial infarction, urinary sodium, atrial sizes, radionuclide left ventricular ejection fraction, workload, baseline and peak-exercise heart rate, baseline and peak-exercise rate-pressure product, duration of exercise. Also baseline atrial natriuretic factor concentrations were similar in both groups (ischaemic patients: 34.51 +/- 15.73 pg/ml; nonischaemic patients: 27.17 +/- 8.74 pg/ml, NS), while peak-exercise atrial natriuretic factor concentrations were higher in patients with exercise-induced myocardial ischaemia (112.31 +/- 35.5 pg/ml) than in the others (80.46 +/- 23.43 pg/ml) (P less than 0.05). After 15 minutes of recovery, plasma atrial natriuretic factor levels were still raised only in the ischaemic patients (63.3 +/- 15.44 pg/ml, P less than 0.01), returning to baseline after 30 minutes in both groups. In control subjects, the behaviour of atrial natriuretic factor resembled that of the patients without exercise-induced ischaemia, with a significant increase at peak-exercise (from baseline levels of 23.1 +/- 10.5 pg/ml to peak-exercise levels of 91.3 +/- 14.5 pg/ml, P less than 0.0005) and a rapid return to baseline levels after 15 minutes of recovery (28.5 +/- 10.6 pg/ml, NS).(ABSTRACT TRUNCATED AT 250 WORDS)     

Lidocaine, mexiletine and propafenone in the treatment of arrhythmias complicating myocardial infarction. A case report

We describe a case of acute myocardial infarction complicated by atrial and ventricular arrhythmias in which it was possible to verify the effectiveness of lidocaine, mexiletine and propafenone. Intravenous administration of mexiletine was ineffective both on atrial and ventricular rhythm disturbances. The lidocaine therapy reduced ventricular ectopic frequency, but did not prevent the appearance of several paroxysms of atrial fibrillation. Intravenous infusion of propafenone, 11 micrograms/kg per min, after a 1 mg/kg i.v. bolus, immediately and completely suppressed atrial arrhythmias. The increase in infusion rate up to 22 micrograms/kg per min also suppressed ventricular ectopy. This dosage of propafenone did not provoke serious adverse effects in our patient.     

Comparative ecotoxicity of single and binary mixtures exposures of cadmium and zinc on growth and biomarkers of Lemna gibba

In the present study, single and mixture effects of cadmium (Cd) and zinc (Zn) on Lemna gibba were analyzed and compared using growth parameters, based on frond number and fresh weight, and biochemical parameters, such as pigment, protein content and activity of antioxidant enzymes. Plants were exposed for 7 days to these metals in nutrient solution. Single and mixture exposures affected plant growth and the biomarkers of the antioxidant response. Considering the growth parameters, Cd was found to be much more toxic than Zn. IC50-7d, based on growth rate calculated on frond number, were 17.8 and 76.73 mg/L, and on fresh weight were 1.08 and 76.93 mg/L, for Cd and Zn respectively. For Cd, LOEC values were obtained at 2.06 and 1.03 mg/L, for frond number and fresh weight respectively; while for Zn, at 20.1 and 74.6 mg/L. A high toxicity effect, considering the same response variables, was observed in plants exposed to the mixtures. Three fixed ratios, based on toxic units (TU) were assayed, ratio 1: 2/3 Cd−1/3 Zn, ratio 2: 1/2 Cd−1/2 Zn and ratio 3: 1/3 Cd−2/3 Zn. Ratio 3 (where Zn was added in higher proportion) was the less toxic. All concentrations of Ratio 1 and 2 significantly inhibited plant growth, showing a 100% inhibition of growth rate at the highest concentrations when based on frond number. Catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APOX; EC 1.11.1.11) and guaiacol peroxidase (GPOX; EC 1.11.1.7) activities in single metals assays were higher than controls. In mixture tests, the activity of APOX and GPOX was significantly stimulated in plants exposed to all evaluated combinations, while CAT was mainly stimulated in Ratio 3. It was observed that the activity of the enzymes was increased in the mixtures compared with similar concentrations evaluated individually. APOX activity was observed to fit the CA model and following a concentration-response pattern. The response of this antioxidant enzyme could serve as a sensitive stressor biomarker for Cd–Zn interactions. Frond number in Cd–Zn mixtures was not well predicted from dissolved metal concentration in solution using concentration addition (CA) as reference model, as results showed that toxicity was more than additive, with an average of ΣTU = 0.75. This synergistic effect was observed up to 50 mg Zn/L in the mixture, but when it was present in higher concentrations a less than additive effect was observed, indicating a protective effect of Zn. A synergistic and dose-ratio deviations from CA model were also observed.     

The diagnostic yield of colonoscopy in hospitalized patients. An observational multicenter prospective study.

BackgroundColonoscopy demands a considerable amount of resources, and little is known about its diagnostic yield among inpatients.AimsTo assess indications, diagnostic yield and findings of colonoscopy for inpatients, and to identify risk factors for relevant findings and cancer.MethodsMulticentre, prospective, observational study including 12 hospitals. Consecutive adult inpatients undergoing colonoscopy were evaluated from February through November 2019.Results1,302 inpatients underwent colonoscopy. Diagnostic yield for relevant findings and cancer was 586 (45%) and 112 (8.6%), respectively. Adequate colon cleansing was achieved in 896 (68.8%) patients. Split-dose/same-day regimen was adopted in 847 (65%) patients. Factors associated to relevant findings were age ≥70 years (RR 1.32), male gender (RR 1.11), blood loss (RR 1.22) and adequate cleansing (RR 1.63). Age ≥70 years (RR 2.08), no previous colonoscopy (RR 2.69) and split-dose/same-day regimen (RR 1.59) significantly increased cancer detection. Implementing adequate cleansing and split-dose/same-day regimen in all patients would increase the diagnostic yield for any relevant findings and cancer from 43% to 70% and from 6% to 10%, respectively.ConclusionRelevant colorectal diseases and cancer were frequent among inpatients. Factors associated with detection of relevant findings were identified. Adequate colon cleansing and split-dose/same-day regimen significantly increased colonoscopy diagnostic yield.     

Then and now: The progress in hepatitis B treatment over the past 20 years

The ultimate goals of treating chronic hepatitis B(CHB)is prevention of hepatocellular carcinoma(HCC)and hepatic decompensation.Since the advent of effective antiviral drugs that appeared during the past two decades,considerable advances have been made not only in controlling hepatitis B virus(HBV)infection,but also in preventing and reducing the incidence of liver cirrhosis and HCC.Furthermore,several recent studies have suggested the possibility of reducing the incidence of recurrent or new HCC in patients even after they have developed HCC.Currently,six medications are available for HBV treatment including,interferon and five nucleoside/nucleotide analogues.In this review,we will examine the antiviral drugs and the progresses that have been made with antiviral treatments in the field of CHB.     

“CADASIL coma” in an Italian homozygous CADASIL patient: comparison with clinical and MRI findings in age-matched heterozygous patients with the same G528C NOTCH3 mutation

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a genetic disorder caused by mutations in the NOTCH3 gene, with a striking variability in phenotypic expression. To date, only two homozygous patients have been reported, with divergent phenotypic features. We describe an Italian CADASIL patient, homozygous for G528C mutation, in whom early manifestation of the disease was migraine, but whose clinical evolution was characterized by a reversible acute encephalopathy followed by full recovery (“CADASIL coma”). Clinical evaluation, MR scan, neuropsychological and neurophysiological investigation did not reveal substantial differences between our homozygous patient and her heterozygous relatives sharing the same mutation, or between our patient and a group of heterozygous individuals with the same mutation but from different families. Skin biopsy identified peculiar features in the homozygous patient, with cytoplasmic pseudoinclusions likely containing granular osmiophilic material (GOM) in the vascular smooth muscle cells, but further studies are necessary to substantiate their possible relationships with CADASIL homozygosis. “CADASIL coma” did not seem to be specific of patient’s homozygosis, since it was observed in one of her heterozygous relatives, whereas its pathogenesis seems to be related to peculiar constellations of unknown predisposing factors. The present study demonstrated that CADASIL conforms to the classical definition of dominant diseases, according to which homozygotes and heterozygotes for a defect are phenotypically indistinguishable.     

SpyGlass® single-operator peroral cholangioscopy in the evaluation of indeterminate biliary lesions: a single-center, prospective, cohort study

Background

SpyGlass^® single-operator peroral cholangioscopy appears to be a promising technique to overcome some limitations of conventional peroral cholangioscopy. We aimed to prospectively evaluate the SpyGlass system in a cohort of patients with indeterminate biliary lesions.

Methods

Patients with indeterminate strictures or filling defects at endoscopic retrograde cholangiopancreatography (ERCP) were consecutively enrolled. After SpyGlass visual evaluation, targeted biopsies were taken with the SpyBite^® and histopathological assessment was made by two experienced gastrointestinal pathologists. SpyBite-targeted biopsy results were evaluated by assessing agreement with surgical specimens and by evaluation of final, clinical follow-up-based diagnosis.

Results

Fifty-two patients participated in the study. In 7 cases, definite diagnosis (stones, varices) was made by SpyGlass endoscopic evaluation. In 42 of the remaining 45 cases, material suitable for histopathology assessment was provided by the SpyBite. Overall, a definite diagnosis was made in 49 (7 + 42; 94 %) cases. Agreement of SpyBite biopsy results with surgical specimen diagnosis was found in 38/42 (90 %) cases; sensitivity, specificity, and positive and negative predictive values were 88, 94, 96, and 85 %, respectively. Procedure-related complications consisted of one case of mild cholangitis and one case of mild pancreatitis.

Conclusions

In our series, the SpyGlass system allowed adequate biopsy sampling and definite diagnosis with high accuracy in the vast majority of patients with indeterminate biliary lesions. Its use was associated with a low complication rate. Further refinements of the technique are warranted, but the SpyGlass system has the potential to become a diagnostic standard for the assessment of indeterminate biliary lesions.     

Refractory gastroesophageal reflux disease as diagnosed by impedance-pH monitoring can be cured by laparoscopic fundoplication

Background

Some patients with typical (heartburn/regurgitation) symptoms of gastroesophageal reflux disease (GERD) are refractory to proton pump inhibitor (PPI) therapy. Impedance-pH monitoring can identify PPI-refractory patients who could benefit from laparoscopic fundoplication, but outcome data are scarce. We aimed to assess whether PPI-refractory GERD as diagnosed by impedance-pH monitoring can be cured by laparoscopic fundoplication.

Methods

Forty-four consecutive GERD patients with heartburn/regurgitation refractory to high-dose PPI therapy entered a 3-year outcome assessment following robot-assisted laparoscopic fundoplication. Preoperative on-PPI impedance-pH diagnostic criteria consisted of positive symptom association probability (SAP)/symptom index (SI), and/or abnormal percentage esophageal acid exposure time (%EAET), and/or abnormal number of total refluxes. GERD cure was defined by 3-year postoperative off-PPI normal impedance-pH findings with persistent symptom remission.

Results

Preoperatively, 24 of 38 (63 %) patients who completed the outcome assessment had a positive SAP/SI, 20 of 38 (53 %) for weakly acidic refluxes; 3 of 38 (8 %) patients had an abnormal %EAET, 11 of 38 (29 %) an abnormal number of total refluxes only. Postoperatively, heartburn/regurgitation recurred in 3 patients; abnormal impedance-pH findings were found in two of them, and they responded to PPI therapy. GERD cure was achieved in 34 of 38 (89 %) patients, 11 of 11 with an abnormal number of total refluxes as the only preoperative abnormal impedance-pH finding. Postoperatively, there was a significant decrease of the %EAET (1 vs. 0.1 %, P = 0.002) and of the number of total refluxes (68 vs. 8, P = 0.001), with the latter finding mainly due to a decrease in the number of weakly acidic refluxes.

Conclusions

Normal reflux parameters and persistent symptom remission at 3-year follow-up can be achieved with laparoscopic fundoplication in the majority of patients with PPI-refractory GERD as diagnosed by impedance-pH monitoring. On-PPI impedance-pH diagnostic criteria should include SAP/SI positivity, an abnormal %EAET, and an abnormal number of total refluxes. Weakly acidic refluxes have a major role in the pathogenesis of PPI-refractory GERD.