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991.
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Introduction

Labyrinthine fistula is one of the most common complications associated with cholesteatoma. It represents an erosive loss of the endochondral bone overlying the labyrinth. Reasons for cholesteatoma-induced labyrinthine fistula are still poorly understood.

Objective

Evaluate patients with cholesteatoma, in order to identify possible risk factors or clinical findings associated with labyrinthine fistula. Secondary objectives were to determine the prevalence of labyrinthine fistula in the study cohort, to analyze the role of computed tomography and to describe the hearing results after surgery.

Methods

This retrospective cohort study included patients with an acquired middle ear cholesteatoma in at least one ear with no prior surgery, who underwent audiometry and tomographic examination of the ears or surgery at our institution. Hearing results after surgery were analyzed according to the labyrinthine fistula classification and the employed technique.

Results

We analyzed a total of 333 patients, of which 9 (2.7%) had labyrinthine fistula in the lateral semicircular canal. In 8 patients, the fistula was first identified on image studies and confirmed at surgery. In patients with posterior epitympanic and two-route cholesteatomas, the prevalence was 5.0%; and in cases with remaining cholesteatoma growth patterns, the prevalence was 0.6% (p = 0.16). In addition, the prevalence ratio for labyrinthine fistula between patients with and without vertigo was 2.1. Of patients without sensorineural hearing loss before surgery, 80.0% remained with the same bone conduction thresholds, whereas 20.0% progressed to profound hearing loss. Of patients with sensorineural hearing loss before surgery, 33.33% remained with the same hearing impairment, whereas 33.33% showed improvement of the bone conduction thresholds’ Pure Tone Average.

Conclusion

Labyrinthine fistula must be ruled out prior to ear surgery, particularly in cases of posterior epitympanic or two-route cholesteatoma. Computed tomography is a good diagnostic modality for lateral semicircular canal fistula. Sensorineural hearing loss can occur post-surgically, even in previously unaffected patients despite the technique employed.  相似文献   
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Clotrimazole (CLT), clinically used as an antifungal drug, inhibited sponge-induced angiogenesis and granulation tissue metabolic activity when administered systemically (120 mg/kg) in rats. We have used functional, biochemical and histological parameters to assess neovascularization and fibrovascular tissue infiltration of the rat sponge granuloma. The sequential development of local blood flow as determined by the outflow rate of sodium fluorescein applied intraimplant, showed that the t 1/2 values for the fluorescence peak in the bloodstream decreased in the control group from an initial value of 11 ± 0.87 min (avascular implants, day 1) to 7.6 ±1.5 min at day 7 postimplantation. By contrast t 1/2 values in the CLT-treated group remained stable during the 7-day period. The hemoglobin content extracted from the control implants was 2.7 ± 0.14 gHb/w.w vs. 1.8 ± 0.18 gHb/w.w in the treated group. The functional and biochemical parameters correlated well with the histological study. Furthermore, the metabolic activity of the sponge-induced granulomas was inhibited by CLT. Because CLT is an inhibitor of signal transduction interfering with the ionic fluxes across the cell membranes, our results suggest that the onset and maintenance of inflammatory angiogenesis induced by subcutaneous implantation of sponge matrix may be regulated by ionic fluxes.  相似文献   
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Nucleotides have been identified as conditionally essential nutrients. As prevention studies, conducted with nucleotide-supplemented formula, have shown statistically significant decrease in the risk of diarrhea, we tested the hypothesis that the consumption of nucleotide-supplemented formula during an acute diarrhea episode is associated with therapeutic effects in the treatment of infants with acute diarrhea and dehydration. A randomized, double-blind, controlled clinical trial was conducted in which patients were randomly assigned to 1 of 2 treatment groups. The “test” group consumed a nucleotide-supplemented infant formula and the “control” group consumed a nonsupplemented formula. Infants were accommodated in a metabolic unit where body weight, and all intakes and outputs were recorded at 24-hour intervals during hospitalization. Laboratory parameters including blood gases and electrolytes were monitored during hospitalization. Eighty-one male infants ranging in age from older than 1 month and younger than 1 year, with acute non-cholera diarrhea and dehydration were studied. Primary outcomes were stool output and duration of diarrhea and did not differ significantly between the groups, with a stool output of 304.2 (SD 254.0) vs 350.3 (SD 269.1) g/kg and a duration of diarrhea of 83.3 (SD 44.5) vs 88.8 (SD 46.6) for the test and control groups, respectively. Anemia was highly prevalent and breast-feeding practice was not frequent in both groups. The average energy intake and weight gain were similar in the 2 groups. This study demonstrated that nucleotide supplementation of infant formula during episodes of acute diarrhea has no therapeutic advantage compared to conventional infant formula.  相似文献   
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Anti-VEGF therapy proved to be useful against several ocular pathological situations, including choroidal neovascularization and proliferative retinopathies. Ranibizumab (Ran), Pegaptanib (Peg) and Bevacizumab (Bev) are the pharmacological agents more frequently used in clinical practice by intravitreal injection. However, their exact effects on the angiogenic process have not been accurately established in a comparative study. The aim of the present study was to elucidate the precise effects of Ran, Peg and Bev on the multiple steps of the angiogenic process. Human umbilical vein endothelial cells (HUVEC) were incubated with each agent within the clinically established concentration range, or identical amounts of the excipients; cell cytotoxicity, proliferation, apoptosis, migration and vessel assembly were assessed. No cytotoxic effects were found for any of the agents studied at any concentration tested. At the clinical dose, cell proliferation was significantly reduced by Bev and Ran, whereas no difference was observed after Peg treatment. In addition, HUVEC apoptosis was effectively increased by Bev and Ran. Cell migration was reduced after incubation with every agent analyzed, though only reaching statistical significance upon Ran intravitreal dose. At clinical doses, capillary assembly was only affected by Bev. In agreement with these data, the active form of VEGF receptor-2 expression was decreased after incubation with Bev (to 66% of control values), Ran (78%) and Peg (86%) relative to controls. These findings indicate that these three agents display distinct effects on endothelial cells.  相似文献   
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Abstract – A case report of the treatment of permanent incisors with crown and root fractures is presented. A radiolucent lesion at the fracture lines was treated with calcium hydroxide in the coronal fragments for 18 months. Clinically, the teeth became firm and the radiographic results after 2 years showed healing of the lesion and hard tissue filling in the space at the fracture lines.  相似文献   
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