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Polyunsaturated fatty acids (PUFAs) are involved both in immune system regulation and inflammation. In particular, within the PUFAs category, omega-3 (ω-3) may reduce inflammation, whereas omega-6 (ω-6) PUFAs are generally considered to have a proinflammatory effect. Recent evidence highlights an imbalance in the ω-3:ω-6 ratio with an increased intake of ω-6, as a consequence of the shift towards a westernized diet. In critical age groups such as infants, toddlers and young children, as well as pregnant and lactating women or fish allergic patients, ω-3 intake may be inadequate. This review aims to discuss the potential beneficial effects of PUFAs on pediatric food allergy prevention and treatment, both at prenatal and postnatal ages. Data from preclinical studies with PUFAs supplementation show encouraging effects in suppressing allergic response. Clinical studies results are still conflicting about the best timing and dosages of supplementation and which individuals are most likely to benefit; therefore, it is still not possible to draw firm conclusions. With regard to food-allergic children, it is still debated whether PUFAs could slow disease progression or not, since consistent data are lacking. In conclusion, more data on the effects of ω-3 PUFAs supplementation alone or in combination with other nutrients are warranted, both in the general and food allergic population.  相似文献   
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This retrospective study investigated the effects of rituximab in 19 pediatric patients (15 girls and 4 boys) with chronic refractory symptomatic immune thrombocytopenic purpura (ITP). Patients received from 2 to 5 weekly infusions of rituximab (375 mg/m(2)); 15 patients were younger than 12 years when treated. The median follow-up time was 30 months (range, 9-43 months). The overall response rate was 68% (13/19 patients). Six responders relapsed at a median of 4.5 months (range, 3-8 months). Seven patients still displayed a platelet count >150,000/microL at a median of 33 months (range, 14-43 months) after rituximab treatment. Six of 15 patients treated with 4 or 5 weekly infusions and 1 of 4 patients treated with 2 or 3 infusions are still in remission. No difference was detected between splenectomized and nonsplenectomized patients. The duration of ITP disease at the time of treatment did not influence the response rate. Patients still in remission showed significantly lower levels of CD19+ cells after 4 and 6 months than nonresponding or relapsed patients (P < .05). No major infections were reported during follow-up. Our data show the efficacy and tolerability of rituximab in young children with refractory symptomatic ITP. Nonrelapsed patients showed a more prolonged B-cell depletion.  相似文献   
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Background: After open or laparoscopic Roux-en-Y gastric bypass (RYGBP) for morbid obesity, the bypassed stomach and duodenum are not readily available for radiological and endoscopic evaluation. Furthermore, little is known about the long-term physiologic and histologic changes that occur in the bypassed GI segments following these procedures. Many alternative radiological and endoscopic techniques have been described to access the distal gastric pouch and the duodenum after RYGBP. Apart from percutaneous gastrografin? studies, all these techniques require the insertion of a gastrostomy tube in the distal stomach. Methods: a new diagnostic method to access the bypassed segments by virtual CT gastroscopy (VG) was used in 5 morbidly obese patients who underwent laparoscopic RYGBP (LRYGBP). Results: All patients tolerated the procedure well, which appears safe and suitable for an outpatient setting.The virtual images offered an excellent intraluminal view of the stomach and duodenum. Conclusions: VG holds promise as the method of choice in the follow-up of LRYGB patients, having the potential to detect inflammatory changes and cancer in the excluded segments early.  相似文献   
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PURPOSE: Implant placement in the posterior maxilla may often be contraindicated because of insufficient bone volume and the presence of the maxillary sinus. In these situations, sinus floor lifting and grafting frequently have been proposed as the best treatment. The aim of this study was to compare histologically the use of 100% autogenous bone versus a combination of autogenous bone and corticocancellous pig bone for maxillary sinus augmentation. MATERIALS AND METHODS: Eighteen patients requiring bilateral maxillary sinus augmentation were selected for this study. Bone for grafting was harvested from the iliac crest. Each patient received 100% autogenous bone in 1 randomly selected sinus (control side) and a 1:1 mixture of autogenous bone and corticocancellous pig bone particles in the contralateral sinus (test side). Five months after the augmentation procedure, bone biopsy specimens were taken at the time of implant placement. RESULTS: No complications were observed during the surgical procedures; all patients healed uneventfully. No signs or symptoms of maxillary sinus disease were observed during the 5 months after surgery. No significant differences in bone percentages were observed in the bone biopsies from test and control sides. DISCUSSION AND CONCLUSION: It could be concluded from this study that corticocancellous pig bone particles can be successfully used in a 1:1 mixture with autogenous bone from the iliac crest for maxillary sinus augmentation in cases of severely atrophic maxilla.  相似文献   
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AIM: To evaluate radiofrequency thermal ablation (RTA) for treatment of cystic echinococcosis in animal models (explanted organs).
METHODS: Infected livers and lungs from slaughtered animals, 10 bovine and two ovine, were collected. Cysts were photographed, and their volume, cyst content, germinal layer adhesion status, wall calcification and presence of daughter or adjacent cysts were evaluated by ultrasound. Some cysts were treated with RTA at 150 W, 80℃, 7 min. Temperature was monitored inside and outside the cyst. A second needle was placed inside the cyst for pressure stabilization. After treatment, all cysts were sectioned and examined by histology. Cysts were defined as alive if a preserved germinal layer at histology was evident, and as successfully treated if the germinal layer was necrotic.
RESULTS: The subjects of the study were 17 cysts (nine hepatic and eight pulmonary), who were treated with RTA. Pathology showed 100% success rate in both hepatic (919) and lung cysts (8/8); immediate volume reduction of at least 65%; layer of host tissue necrosis outside the cyst, with average extension of 0.64 cm for liver and 1.57 cm for lung; and endocyst attached to the pericystium both in hepatic and lung cysts with small and focal de novo endocyst detachment in just 3/9 hepatic cysts.
CONCLUSION: RTA appears to be very effective in killing hydatid cysts of explanted liver and lung. Bile duct and bronchial wall necrosis, persistence of endocyst attached to pericystium, should help avoid or greatly decrease in v/vo post-treatment fistula occurrence and consequent overlapping complications that are common after surgery or percutaneous aspiration, injection and reaspiration. In vivo studies are required to confirm and validate this new therapeutic approach.  相似文献   
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