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91.
In the present study the olfactory system of hereditary ataxia patients was tested using the smell identification test. Two previous findings suggested a possible olfactory impairment in these patients. First, an olfactory dysfunction has been found in different neurodegenerative diseases, and second, human functional imaging has shown cerebellar activation during olfaction. As an initial approach to determine if cerebellar ataxia impairs the olfactory process, cerebellar ataxia patients, along with basal ganglia patients, were tested. The results show an olfactory deficit in both basal ganglia and hereditary ataxia patients. Further exploration of the olfactory capacities in hereditary ataxia is necessary to elucidate the specific nature of the deficits.  相似文献   
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The effect of carboplatin (CPt) on fibrin(ogen) clot formation and the possible use of this combination for local slow release chemotherapy were examined. CPt significantly reduced thrombin-induced fibrin clotting time (CT) and increased clot turbidity in a concentration-dependent manner. When CPt was mixed with physiological levels of fibrinogen (>1 mg/ml), electron-dense nanoparticles (3 nm) were formed, as demonstrated by both optical particle counter and transmission electron microscopy (TEM). Upon thrombin-induced coagulation, the CPt nanoparticles were trapped within the fibrin mesh. At higher fibrinogen levels (>5 mg/ml), the 3-nm CPt nanoparticles aggregated, so that approximately 2% and approximately 0.5% of the CPt on the fibrinogen appeared as larger particles of 10 and 50 nm, respectively. Dialysis experiments showed that 60-70% of the CPt was released from the fibrin clot within one hour as a non-particulate soluble form, while approximately 30% of particulate CPt were retained. Up to 5 mg/ml this portion of firmly attached CPt was dependent of the initial drug level. CPt released from the fibrin by either diffusion or by fibrinolysis exhibited cytotoxic activity towards retinoblastoma (RB) cell lines (Y-79 and Weri RB1) equivalent to free drug. Our study indicates that CPt enhances fibrin clot formation and suggests the use of fibrin with high dose CPt for slow release chemotherapy against localized tumors such as retinoblastoma.  相似文献   
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Background: Atherosclerosis begins in childhood and is influenced by risk factors for coronary heart disease (CHD), of which hypercholesterolemia is crucial. The rationale for treating hypercholesterolemia in childhood is to limit atherosclerosis development, for which adherence to a cholesterol-lowering diet is the first-choice therapy. Nevertheless, pharmacological intervention with bile acid-binding resins may be prescribed for patients older than 10 years, mainly those with family history of CHD, multiple risk factors, and/or severe hypercholesterolemia. Resins are effective and tolerable in this population, but their clinical use has been limited because of poor compliance due to unpalatability; other effective cholesterol-lowering drugs have not been recommended in this population because of the potential impact of drug-related adverse effects such as increases in transaminases, myopathies, and gastrointestinal disturbances. Thus, the need for safer, easy-to-take, and effective cholesterol-lowering agents for this population continues. Policosanol is a mixture of higher primary aliphatic alcohols purified from sugar cane wax with cholesterol-lowering effects proven in patients with type II hypercholesterolemia and dyslipidemia due to type 2 diabetes mellitus. Policosanol shows good safety and tolerability profiles, with no evidence of drug-related adverse events (AEs) to date. This background supports the idea that policosanol could be a good candidate for treating hypercholesterolemia in children and adolescents, but it requires clinical demonstration.Objective: This 12-week study was undertaken to investigate the cholesterol-lowering effects and tolerability of policosanol in hypercholesterolemic patients aged 11 to 19 years.Methods: In this randomized, double-blind, placebo-controlled study, after 4 weeks of dietary stabilization, adolescents with type II hypercholesterolemia were randomly assigned (1:1 ratio) to receive placebo or policosanol 5-mg tablets once daily for 12 weeks. Physical examinations were performed, and lipid profiles and blood samples were obtained at baseline and after 6 and 12 weeks of therapy. The treatment was considered effective if mean reductions of low-density lipoprotein cholesterol (LDL-C) were >15%. In addition, the percentages of patients reaching final values of LDL-C <3.4 mmol/L and optimal values of <2.8 mmol/L were also evaluated. The doses were doubled if LDL-C values were ≥3.4 mmol/L after 6 weeks of therapy. The incidence of AEs and compliance with study medications were also evaluated after 6 and 12 weeks of treatment.Results: Fifty-five patients were enrolled in the study (28 policosanol, 27 placebo). Twenty-three patients (17 placebo, 6 policosanol) required dose titration at 6 weeks. After 12 weeks of therapy, policosanol significantly decreased LDL-C with respect to baseline and placebo (both P < 0.001), showing a mean reduction of 32.6%. Total cholesterol (TC) and TC/high-density lipoprotein cholesterol (HDL-C) and LDL-C/HDL-C ratios were reduced by 21.9%, 27.8%, and 37.2%, respectively, in the policosanol group (P < 0.001, compared with baseline and placebo). HDL-C rose 10.1% (P < 0.001), compared with baseline and placebo. Triglycerides were unaffected by policosanol. LDL-C, TC, and both atherogenic ratios were reduced significantly in the policosanol group (P < 0.001), and significant increases in HDL-C values were observed at the 6-week interim checkup (P < 0.001 vs baseline, P < 0.01 vs placebo). Twenty-five (89.3%) of 28 patients in the policosanol group showed LDL-C reductions >15% compared with 2 (7.4%) of 27 patients in the placebo group (P < 0.001). In addition, 26 (92.8%) of 28 policosanol patients reached LDL-C values < 3.4 mmol/L compared with 4 (14.8%) of 27 patients in the placebo group (P < 0.001). Likewise, the response rate for achievement of optimal values (LDL-C < 2.8 mmol/L) was also larger in the policosanol group (20/28; 71.4%) than in the placebo group (0/27; 0.0%) (P < 0.001). Policosanol was well tolerated, with no drug-related effects found on physical examination. Blood biochemistry determinations revealed significantly lower alanine aminotransferase levels in the policosanol group after 6 weeks of therapy compared with placebo (P < 0.05), as well as significant reductions in aspartate aminotransferase levels at 6 weeks (P < 0.01) and 12 weeks (P < 0.05) compared with baseline. No patients withdrew from the study, and only 3 patients (2 placebo, 1 policosanol) experienced mild AEs during the study; the placebo patients reported abdominal pain and constipation (1 each), and the policosanol patient reported polyphagia.Conclusions: Policosanol 5 mg/d appears to be well tolerated and effective as short-term treatment of hypercholesterolemia in adolescents.  相似文献   
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Arylsulfatase A (ASA) is a lysosomal enzyme involved in the catabolism of cerebroside sulfate. ASA deficiency is associated with metachromatic leukodystrophy (MLD). Low ASA activities have also been reported in a more common condition with no apparent clinical consequences termed ASA pseudo-deficiency (ASA-PD) which is associated with two linked mutations in the ASA gene (c.1049A>G and c.*96A>G). This study aimed to investigate the frequency of the two ASA-PD variants and their linkage disequilibrium (LD) among Tunisians. ASA-PD variants were detected in 129 healthy Tunisians and their frequencies were compared to those described worldwide. The frequency of the PD allele was estimated at 17.4 % for the overall sample, with c.1049A>G and c.*96A>G frequencies of 25.6 and 17.4 %, respectively. This study also revealed a high LD between the two ASA-PD variants (r 2 = 0.61). Inter-population analysis revealed similarities in the ASA-PD genetic structure between Tunisians and populations from Middle East with c.*96A>G frequencies being the highest in the world. A significant North vs. South genetic differentiation in the ASA-PD frequency was also observed in Tunisian population who seems genetically intermediate between Africans, Middle-Easterners and Europeans. This is the first report on the allele frequency of the ASA-PD in North Africa, revealing a relatively high frequency of the PD allele among Tunisians. This study gives also evidence on the importance of discriminating ASA-PD allele from pathological mutations causing MLD and supporting enzymatic activity testing with both sulfatiduria determination and genetic testing in the differential diagnosis of MLD in the Tunisian population.  相似文献   
99.
BACKGROUND/AIMS: To compare patients with gallbladder cancer treated with radical resection and regional lymphadenectomy (RR-RL) versus simple cholecystectomy and adjuvant external radiotherapy (SC-ERT) and determine outcome. METHODOLOGY: Presentation, operative data, complications and survival were examined in 137 patients. In particular, the 45 patients treated with RR-RL or SC-ERT. RESULTS: Twenty-five had SC-ERT and 20 had a RR-RL. There were no epidemiological differences between groups. Resection of segments IV-b and V and en bloc dissection of regional lymph nodes was the most frequently used procedure (75%). The morbidity and mortality of the radical procedure were 25% and 10%. The morbidity of SC-ERT was 16%. All patients with Nevin I are alive. For lesions Nevin II and Nevin III RR-RL offered a 100% 5-year survival rate and SC-ERT had a 62% and 39% 5-year survival rate respectively. For lesions Nevin IV and V there was no difference in long-term survival. CONCLUSIONS: RR-RL is better than SC-ERT in patients with Nevin II and III lesions because it improves survival rate. SC-ERT can be recommended as an alternative treatment. For more advanced lesions further trials are needed.  相似文献   
100.
Maternal and Child Health Journal - Evidence suggests that the association between dietary energy density (DED) and body composition in children is different than in adults. The purpose of this...  相似文献   
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