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1.

Background

One daily dose of tacrolimus (QDT) improves adherence in kidney transplant (KT) recipients. A switch from twice-daily tacrolimus (BDT) to QDT showed similar efficacy and safety.

Methods

The aim of our study was to demonstrate the long-term efficacy and safety of switching from BDT to QDT in KT recipients. Preliminary results have already been published. Forty-one patients (34 men and 7 women), mean age at KT of 43.9 ± 12.7 years, underwent a 1:1 dose switch from BDT to QDT; the mean time from KT to switch was 36.6 ± 16.1 months. In our study population, 4 patients received a living donor KT and 2 received a second allograft.

Results

The mean follow-up was 86.8 ± 13 months from the switch and 126.2 ± 22.3 months from KT. Graft and patient survival rates were 90.2% and 95.1%, respectively. All patients maintained stable renal function during follow-up. During the first 3 months after the switch we observed a significant decrease in tacrolimus blood level (P = .0001). No significant differences were observed regarding tacrolimus dose before and after QDT introduction (P = not significant [NS]). Fourteen patients who stopped steroids under BDT treatment and 16 patients who stopped steroids after the switch are currently steroid-free.

Conclusion

Our study showed safety and efficacy in switching from BDT to QDT. After early (<1 year) dose adjustment, tacrolimus blood levels remained stable throughout follow-up. Moreover, QDT represented a valid alternative for patients showing steroid side effects.  相似文献   
2.
Global migration from several plastics (phthalate-plasticized PVC, polyurethane, polyether-polyamide copolymer and silicone rubber) into olive oil, used as a liquid simulant for fatty foods, was compared with global migration into isooctane, which has been proposed as a new fatty-food simulant. The results showed that the isooctane test (involving contact for 2 hr at 40 degrees C) is not suitable as a substitute for the olive oil test (contact for 10 days at 40 degrees C) for some types of commercial plastic materials.  相似文献   
3.
Summary To evaluate the influence of the stomach and the cholinergic system on gallbladder contraction induced by physiological stimuli, the reduction in gallbladder volume in 7 healthy volunteers has been studied by real-time ultrasonography after the oral and intraduodenal administration of olive oil, preceded by pretreatment with cimetropium bromide or placebo. After an overnight fast, each subject swallowed 50 ml olive oil or it was administered through a naso-duodenal tube in the proximal duodenum. Cimetropium bromide 5 mg or placebo was given intravenously under double-blind control.After the placebo pretreatment, gallbladder contraction was greater and faster after intraduodenal oil than after oral oil. Cimetropium bromide decreased the extent, velocity and duration of gallbladder contraction induced by intraduodenal olive oil but it only reduced the velocity of the contraction induced by oil given orally.It is concluded that in normal human subjects the stomach modulates the extent and velocity of postprandial gallbladder contraction and that anticholinergic agents antagonize the gastric and duodenal phases of the response of the gallbladder to a meal.  相似文献   
4.
The 5-HT1 agonist sumatriptan (SUM) elicits an increase in amplitude of oesophageal motor waves and of lower oesophageal sphincter (LOS) tone in healthy subjects. The aim of the study was to evaluate whether such an effect occurs also in patients with ineffective oesophageal motility (IOM). 16 patients (nine males and seven females, age range 34-55 years) with chest pain and mild to moderate dysphagia were studied; all had undergone previous cardiologic, radiologic and upper gastrointestinal endoscopic exams that were normal. An oesophageal manometry was performed using an electronic probe to record swallows, oesophageal, LOS and gastric motility. The patients whose motor pattern were compatible with IOM (>30% of motor waves with amplitude <30 mmHg and/or non-transmitted) received SUM or placebo 6 mg s.c., injected in the morning and in the afternoon in a random order. The data analysis was limited to 1 h before and 1 h after the drug injections. Ten out of the 16 patients showed an IOM motor pattern. The administration of SUM caused a significant increase in the number of swallows (SUM 99.5 +/- 15.4 vs 78.6 +/- 16.1 basal, P = 0.03) and of primary oesophageal motor waves (SUM 89.6 +/- 13.4 vs 67.2 +/- 12.9 basal, P = 0.04) with no significant changes in the percentage of swallows associated with propagation. Placebo was not associated with increase in the number of swallows (80.3 +/- 14.6, P = 0.9) or of primary oesophageal motor waves (70.1 +/- 12.3, P = 0.7). The amplitude and the percentage of propagated oesophageal motor waves as well as the mean basal LOS tone were unaltered by SUM. There was no change in the symptoms reported after SUM. Although effective in healthy subjects, SUM 6 mg s.c. improves only the numbers but not the amplitude or propagation of oesophageal motility of patients with IOM. The 5-HT1 pathway and its acute stimulation seem to play only a minor role in the pathogenesis of such a disease.  相似文献   
5.
6.
The risk of mother-to-infant transmission of hepatitis C virus (HCV) varies according to the population studied and the tests used. Aim of the current study was to investigate HCV vertical transmission rate in children born to 30 HCV positive/HIV negative pregnant women in Italy. We investigated the potential vertical transmission of HCV by identifying HCV antibody seropositive pregnant women, by analyzing HCV-RNA in the peripheral blood using PCR and by prospectively following their offspring until 24 months of age. During the third trimester, 2,980 consecutive pregnant women were examined for anti-HCV antibodies by a second generation Enzyme-Linked Immunosorbent Assay (EIA2) and re-assayed by a second generation Recombinant Immunoblot Assay (RIBA2). A total of 32 mothers (1.07%) were positive for EIA2 test; 30 out of 32 had a reactive confirmatory RIBA2 test for HCV All anti-HCV positive mothers were negative for HIV. These 30 mothers and their 30 babies formed the study cohort. Of the 30 anti-HCV positive mothers, 10 were also positive for serum HCV-RNA by PCR. All the babies born to the 30 anti-HCV positive mothers were initially negative for HCV-RNA (cord blood specimens), but three babies became positive at three months of age and remained positive thereafter. These babies had been born to 3 of the 10 mothers with viremia during the third trimester of pregnancy. These results suggest that HCV vertical transmission is possible in 10% of anti-HCV positives and in about 33% of the HCV-RNA seropositive mothers.  相似文献   
7.
OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms.  相似文献   
8.
Heartburn is the most specific symptom of gastroesophageal reflux disease (GERD). In clinical practice, heartburn relief by a proton pump inhibitor (PPI) trial does suffice to confirm GERD. However, an objective diagnosis of GERD is required before anti-reflux endoscopic or surgical interventions, independently from PPI response. Thus, since normal findings at upper endoscopy are detected in the majority of patients with heartburn, reflux monitoring is often required. When traditional catheter-based or wireless pH tests are used, reflux episodes are conventionally identified by pH drops below 4.0 units. Combined impedance-pH monitoring has the advantage to provide a comprehensive assessment of both physical and chemical properties of refluxate and the distinction between acid and weakly acidic refluxes, both proven to cause heartburn. Unfortunately, the conventional impedance-pH parameters, namely acid exposure time and number of reflux events, are characterized by suboptimal diagnostic sensitivity, and the reliability of symptom–reflux association indexes remains questionable. Therefore, novel impedance parameters, namely the post-reflux swallow-induced peristaltic wave (PSPW) index and the mean nocturnal baseline impedance (MNBI), have recently been proposed in order to achieve a better diagnostic yield. In fact, they proved to be highly accurate in distinguishing reflux-related from reflux-unrelated heartburn, off- as well as on-PPI therapy. Currently, manual review of impedance-pH tracings is needed because of the modest accuracy of available software tools for automated analysis. PSPW index and MNBI are highly applicable and reproducible, and their calculation requires a few additional minutes during the manual review of impedance-pH tracings. So far, we believe that PSPW index and MNBI are ready for prime time and should become part of the standard analysis of impedance-pH tracings for GERD diagnosis in patients with endoscopy-negative heartburn.  相似文献   
9.
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.  相似文献   
10.
Rifaximin in patients with lactose intolerance   总被引:1,自引:0,他引:1  
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.  相似文献   
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