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Verocytotoxin-producing Escherichia coli(VTEC) infections cause most cases of hemolytic uremic syndrome (HUS); 10-30% of patients, however, are negative for VTEC infection. The etiology of HUS in VTEC-negative cases remains poorly understood. Before the association between VTEC infection and HUS was recognized, sporadic cases of HUS with enterovirus infection were reported in the literature. Since May 1988, most cases of HUS in Italy have been reported to the Italian surveillance system, and in 73% of these, evidence of VTEC infection was demonstrated. The aim of this study was to determine whether the frequency of enteroviral infections was different in the acute phase of VTEC-positive and VTEC-negative HUS. Eighty-nine patients were investigated for enteroviral infection, of whom 58 were VTEC positive and 31 VTEC negative. Two serum samples from each patient were examined for seroconversion to enterovirus (coxsackie, echovirus, and picornavirus) by a complement fixation test. Serological evidence of acute infection with non-polio enterovirus was found in 33 patients (37%) [20/58 (34.5%) VTEC positive and 13/31 (41.9%) VTEC negative]. There was no statistically significant difference between the two groups. These results demonstrate that there are no significant differences for enteroviral infection in VTEC-positive and VTEC-negative patients and, therefore, enteroviral infections should not be considered a cause of HUS in VTEC-negative children.  相似文献   
43.
In this report, the authors review the case of a man with a neurocutaneous syndrome. He presented with an intracerebral melanocytoma associated with a blue nevus of the scalp; its location and its appearance during childhood supported the diagnosis of a nevus of Ota. Meningeal melanocytomas are increasingly being diagnosed, but remain rare. Primary meningeal malignant melanoma is the first differential diagnosis to eliminate. Despite their common embryonic origin. the association of a melanocytoma with a nevus of Ota is rare. A nevus of Ota exhibits the same melanocytic proliferation and affects the trigeminal nerve territory. An ocular effect is not always observed. In contrast to an ocular lesion, a nevus of Ota rarely transforms into a malignant melanoma. It is found only among caucasians. During 4 years of follow-up review after surgery, the patient remained asymptomatic. Other than antiepileptic therapy, he received no complementary treatment and cerebral imaging revealed no evidence of recurrence.  相似文献   
44.
BACKGROUND: Fistulous communications between the accessory right hepatic (ARHA), gastroduodenal (GD), and superior mesenteric (SMA) arteries and the portal vein (PV) may represent a contraindication for liver transplantation (LT). MATERIAL: A patient with HCV-related liver cirrhosis and progressive liver decompensation underwent preoperative LT work-up. Doppler ultrasound (DU), Angiography and MRI revealed arteroportal fistulas (APF) and diversion of mesenteric-splenoportal flow through spontaneous splenorenal shunts (SSRS) in the systemic circulation. The patient was transplanted and the ARHA and GDA were distally sectioned; the HA was anastomosed to the donor HA; the superior mesenteric vein (SMV) was detached from the splenopancreatic venous bed by sectioning and ligating the Henle trunk, by ligating an posterior-inferior pancreatic vein and, finally, by positioning an iliac vein interposition graft between the SMV and the donor PV. The postanastomotic SMV trunk and recipient PV were ligated below and above the pancreatic head, respectively. RESULTS: Reperfusion and late liver function were good. DU and MRI studies showed an effective portal flow and the maintenance of a normal splenopancreatic vein outflow through the SSRS. DISCUSSION: APF represent a serious clinical problem, particularly in patients who need LT. The persistence of arterial flow into the PV is dangerous for the long-term liver function. A particular surgical strategy, strictly tailored to the hemodynamic conditions, has to be planned. CONCLUSIONS: Extrahepatic multiple APF would no longer to represent a contraindication to LT, although this claim needs to be confirmed in the light of further experience and a longer-term follow-up.  相似文献   
45.
Background The future remnant liver (FRL) limit for safe major hepatectomy with low risk of postoperative liver failure has not yet been well defined. Methods Between April 2000 and September 2004, every patient scheduled for major hepatectomy in our institution underwent CT-volumetry of FRL. Patients with FRL <25% underwent portal vein embolization (PVE). Exclusion criteria were PVE, associated vascular resection and liver cirrhosis. The FRL was correlated with short-term results in patients with normal liver (group A) and those with impaired liver function secondary to neoadjuvant chemotherapy or cholestasis (bilirubin >2 mg/100 ml) (group B). Liver dysfunction was defined as both PT <50% and serum bilirubin level >5 mg/100 ml for three or more consecutive days. Results A total of 119 patients were analyzed, 72 in group A and 47 in group B. The FRL value was the only significant risk factor for postoperative liver dysfunction in the univariate and multivariate analysis (p = 0.009). The FRL did not correlate with postoperative mortality and morbidity. Bilirubin and prothrombin time (PT) on days 3 and 7 were significantly correlated to FRL in both groups. In group A, patients with postoperative liver dysfunction had a FRL<30% (3 versus 0; p = 0.005). According to receiving operator characteristic (ROC) curve analysis, a FRL value of 26.5% predicted postoperative liver dysfunction with 66.7% sensitivity, 97.1% specificity, 50% positive predictive value (PPV), and 98.5% negative predictive value (NPV). In group B, patients with postoperative liver dysfunction had a FRL <35% (4 versus 0; p = 0.027). According to ROC curve analysis, a FRL value of 31.05% predicted postoperative liver dysfunction with 75% sensitivity, 79.1% specificity, 25% PPV, and 97.1% NPV. Conclusions Hepatectomy can be considered safe when FRL is >26.5% in patients with healthy liver and >31% in patients with impaired liver function.  相似文献   
46.
Cannabidiol (CBD) is a major constituent of the Cannabis sativa plant. It inhibits the anxiogenic activity of high doses of Δ9-tetrahydrocannabinol and induces anxiolytic-like effects. However, the mechanisms underlying the actions of CBD are unknown. Therefore, the aim of the present study was to test the effects of CBD in the Vogel test, a widely used animal model of anxiety. In addition, it was verified if these effects would depend on benzodiazepine-receptor activation. After 24 h of water deprivation, male Wistar rats were subjected to an initial 3-min non-punished (pre-test) drinking session. This was followed by an additional 24-h period of water deprivation followed by a 3-min punished-licking session (test). Diazepam (3 mg/kg) or CBD (2.5, 5 or 10 mg/kg) were intraperitoneally injected 30 min before the test session. CBD (10 mg/kg) and diazepam had similar anticonflict effects, increasing the number of punished licks. The effect of diazepam, but not of CBD, was prevented by the benzodiazepine-receptor antagonist flumazenil (10 mg/kg). To exclude that the anticonflict effects were reflecting non-specific drug effects, we checked the effects of CBD on water consumption and nociceptive response. The drug did not interfere on the former variable in a non-punished test session. Moreover, contrary to morphine (5 mg/kg), CBD was ineffective in the tail-flick test. In conclusion, CBD induced an anticonflict effect not mediated by benzodiazepine receptors or by non-specific drug interference on nociceptive threshold or water consumption. These results reinforce the hypothesis that this cannabinoid has anxiolytic properties.  相似文献   
47.
In mammals, sensory neurons from the main olfactory and vomeronasal systems project their axons to the olfactory bulbs in the brain. We here report that a cluster of neurons, distinct from these two systems, located at the very tip of the mouse nose and called the Grüneberg ganglion expresses the mature olfactory-sensory neuron-specific marker olfactory marker protein (OMP), but is unlikely to express known odorant or pheromone receptors. The ganglion is present at birth and maintained during adult life. Tracing experiments indicate that these neurons target ipsilaterally to a specific set of glomeruli located on the caudal part of the olfactory bulb, and that this connection is necessary for the survival of the ganglion. The glomerular targets are structures previously proposed to be associated with suckling behaviour. These observations strongly suggest that this peculiar olfactory neuronal population plays a sensory role, possibly linked to chemoperception.  相似文献   
48.
49.
BACKGROUND: A surgical approach based on ultrasound-guided hepatectomy might minimize the need for major resection, whose rates of morbidity and mortality are not negligible. Right hepatectomy (RH) is traditionally performed in cases of vascular invasion of the right hepatic vein with multiple tumors in the right posterior section, and/or of the right posterior portal branch (P6-7) with tumor in contact with right anterior portal branch (P5-8). We herein describe an alternative approach to RH consisting in ultrasound-guided systematic extended right posterior hepatic sectionectomy (SERPS). METHODS: Among 207 consecutive patients who underwent hepatectomies, 21 (10%) underwent SERPS. Median age was 67 years (range, 48-79). There were 13 men and 8 women. Ten (48%) patients had hepatocellular carcinoma; 11 (52%) had colorectal liver metastases. Median tumor number was 2 (range, 1-15); median tumor size was 4.5 cm (range, 2.5-20). Ten (48%) patients had cirrhosis, 8 (38%) had steatosis, and 3 (16%) had normal liver. Surgical strategy was based on tumor-vessels relationship at intraoperative ultrasonography (IOUS) and on findings at color-Doppler IOUS. RESULTS: In-hospital and 90-days mortality were nil. Major and minor morbidity occurred in 3 (14%) and 2 (9.5%) patients, respectively. No patients were reoperated because of complications. Blood transfusions were given to 2 (9.5%) patients. After a median follow-up of 21 months, no local recurrence was observed. CONCLUSIONS: IOUS-guided SERPS is feasible, safe, and effective. It should be applied whenever possible as alternative resection to RH to maximize liver parenchymal sparing.  相似文献   
50.
The best prioritization of patients with hepatocellular carcinoma (HCC) waiting for liver transplantation under the model for end-stage liver disease (MELD) allocation system is still being debated. We analyzed the impact of a MELD adjustment for HCC, which consisted of the addition of an extra score (based on the HCC stage and waiting time) to the native MELD score. The outcome was analyzed for 301 patients with chronic liver disease listed for liver transplantation between March 1, 2001 and February 28, 2003 [United Network for Organ Sharing (UNOS)-Child-Turcotte-Pugh (CTP) era, 163 patients, 28.8% with HCC] and between March 1, 2003 and February 28, 2004 (HCC-MELD era, 138 patients, 29.7% with HCC). In the HCC-MELD era, the cumulative dropout risk at 6 months was 17.6% for patients with HCC versus 22.3% for those patients without HCC (P = NS), similar to that in the UNOS-CTP era. The cumulative probability of transplantation at 6 months was 70.3% versus 39.0% (P = 0.005), being higher than that in the UNOS-CTP era for patients with HCC (P = 0.02). At the end of the HCC-MELD era, 12 patients with HCC (29.3%) versus 57 without HCC (58.8%) were still on the list (P = 0.001). Both native and adjusted MELD scores were higher (P < 0.05) and progressed more in patients with HCC who dropped out than in those who underwent transplantation or remained on the list (the initial-final native MELD scores were 17.3-23.1, 15.5-15.6, and 12.8-14.1, respectively). The patients without HCC remaining on the list showed stable MELD scores (initial-final: 15.1-15.4). In conclusion, the present data support the strategy of including the native MELD scores in the allocation system for HCC. This model allows the timely transplantation of patients with HCC without severely affecting the outcome of patients without HCC.  相似文献   
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