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31.

Objective

OSD-6 is a disease specific questionnaire for pediatric obstructive sleep apnea (OSA). The aims of this study were to validate OSD-6 in Greek language and correlate OSD-6 with polysomnography results.

Study design

Prospective study.

Setting

Tertiary referral center.

Subjects and methods

OSD-6 questionnaire was translated to Greek and back to English. A prospective study was conducted on children undergoing overnight polysomnography due to snoring and disrupted sleep. Test–retest evaluation was carried out. Internal consistency and test–retest reliability were evaluated. Validity was assessed by exploring correlations between OSD-6 scores and apnea–hypopnea index (AHI), and by comparing total scores of OSA and non-OSA groups. Responsiveness was assessed by comparing preoperative to postoperative total scores in OSA children who underwent adenotonsillectomy.

Results

Test–retest evaluation of 91 subjects showed good internal consistency (Cronbach’s alpha 0.860 for test and 0.873 for retest) and reliability (Pearson’s correlation coefficients between test and retest scores: 0.751–0.546; p < 0.01). Total and domains’ OSD-6 scores and AHI were significantly correlated (Spearman’s correlation coefficients: 0.277–0.630; p < 0.01), while children with OSA had higher total OSD-6 score than those without OSA (median (interquartile range): 16 (11) vs. 10 (7), respectively; p < 0.01), indicating good validity. Postoperative OSD-6 scores were significantly lower than preoperative (2.84 ± 3.21 vs. 15.42 ± 6.48, respectively; p < 0.001), suggesting good responsiveness.

Conclusion

The Greek version of the OSD-6 questionnaire proved to be a valid instrument with satisfactory internal consistency, reliability, validity and responsiveness. Furthermore, in our study OSD-6 was significantly correlated to polysomnography results.  相似文献   
32.
Factor XI (FXI) is a procoagulant factor and antifibrinolytic agent, and its absence causes a bleeding tendency. FXI deficiency is autosomal in inheritance, with severe FXI deficiency in homozygotes and partial deficiency in heterozygotes. A 24-year-old primigravida with an uneventful pregnancy and no history of bleeding manifestations was admitted to our department at 38 weeks of gestation. Her blood count and serum biochemistry findings were normal except for a coagulation screen, which revealed a prolonged activated partial thromboplastin time (APTT) of 63 seconds (normal range, 24-35 seconds). The measured FXI coagulant activity of 8 IU/dL (reference range, 70-150 IU/dL) established a diagnosis of severe FXI deficiency. The breech presentation of the fetus prompted the decision for cesarean delivery under general anesthesia. We administered a single dose of FXI concentrate (15 IU/kg), which corrected the APTT to 34 seconds. The cesarean delivery was uncomplicated, and postpartum recovery of the mother and her baby was uneventful with no bleeding complications. The finding of an isolated prolonged APTT should prompt obstetricians to consider FXI deficiency. The appropriate use of factor FXI concentrate in managing obstetric patients with FXI deficiency can minimize potential bleeding complications and ensure an optimal outcome for both mother and neonate.  相似文献   
33.
BACKGROUND AND AIMS: Initiation of a fibrotic process has been suggested as part of the intestinal response to chronic inflammation in inflammatory bowel disease. YKL-40 has been proposed as a new serum marker of fibrosis. We studied compared the serum levels of YKL-40 in patients with ulcerative colitis or Crohn's disease with inflammatory and healthy controls. PATIENTS AND METHODS: YKL-40 serum levels were measured in 179 patients with inflammatory bowel disease (94 ulcerative colitis, 85 Crohn's disease), in 23 with intestinal inflammation of other causes, and 70 matched healthy controls using a commercially available enzyme-linked immunosorbent assay. YKL-40 levels were assessed in terms of disease activity, type and localization. RESULTS: Mean serum YKL-40 levels were 102.6+/-82.7 ng/ml in ulcerative colitis patients and 112.2+/-83.7 ng/ml in Crohn's disease patients, significantly higher than in healthy controls (64.1+/-21.4 ng/ml) but not significantly different from inflammatory controls (77.8+/-23.1 ng/ml). Disease activity and C-reactive protein levels were significantly correlated with YKL-40 levels in both ulcerative colitis and Crohn's disease. Crohn's disease patients with ileum localization had significantly higher YKL-40 levels than those with ileocolonic or colonic disease. Patients with stenotic disease had mean YKL-40 levels not significantly different than those with nonstenotic disease. CONCLUSION: Serum levels of YKL-40 are increased in patients with inflammatory bowel disease, and this is associated with the inflammatory process rather than with the degree of fibrosis.  相似文献   
34.
STUDY OBJECTIVES: Obstructive sleep-disordered breathing is accompanied by episodic increases in left ventricle afterload due to large negative swings in intrathoracic pressure and repetitive surges in arterial pressure. Brain natriuretic peptide (BNP) is released by ventricular myocytes in response to pressure and volume overload. It was hypothesized that in children with snoring, overnight change in BNP levels is correlated with severity of disturbance in respiration. DESIGN: Evening and morning plasma levels of BNP were measured in children with snoring referred for polysomnography. SETTING: A sleep disorders laboratory in a university hospital. PARTICIPANTS: Twenty-two children with apnea-hypopnea index (AHI) > or = 5/h (mean +/- SD age, 6.4 +/- 2.5 years), 60 children with AHI < 5/h (mean age, 7 +/- 2.9 years), and 27 control subjects without snoring (mean age, 7.8 +/- 3.7 years) were recruited. MEASUREMENTS AND RESULTS: Overnight change in BNP (log-transformed ratio of morning-to-evening levels) was larger in children with AHI > or = 5/h, compared to those with AHI < 5/h or to control subjects (0.1 +/- 0.19 vs 0.01 +/- 0.14 vs - 0.06 +/- 0.18; p < 0.05). Children with AHI > or = 5/h had an odds ratio of 4.33 (95% confidence interval, 1.34 to 14) for change in peptide levels > 0.15 relatively to subjects with AHI < 5/h. AHI and oxygen saturation of hemoglobin nadir were significant predictors of overnight change in peptide levels. CONCLUSIONS: In children with snoring, overnight increase in BNP levels is correlated with severity of disturbance in respiration during sleep, which may indicate presence of nocturnal cardiac strain.  相似文献   
35.
36.
The severe endothelial dysfunction in children with acute lymphoblastic leukemia (ALL) can result from the disease itself, from treatment, or from other conditions (e.g. sepsis). The aim of this study was to determine the levels of markers of endothelial activation in children with ALL and to assess their potential prognostic value. Fifty-two children with ALL, 19 children with ALL 1-10 years after the completion of therapy, and 28 healthy children were studied. In children with ALL, there was a significant increase in thrombomodulin (TM) and von Willebrand factor (vWF) levels during the acute phase of the disease and during treatment. Children with an unfavorable outcome had higher levels of TM. In conclusion, severe endothelial dysfunction is present during the acute phase of ALL and during treatment and appears to result from the disease itself. Serum TM and vWF levels might represent additional, but not independent, prognostic markers in childhood ALL.  相似文献   
37.
The most frequent defects resulting in alpha-thalassemia (thal) include large deletions that remove one or both of the duplicated alpha-globin genes on chromosome 16. Less commonly, alpha-thal mutations involve single nucleotide substitutions or micro-deletions, leading either directly to decreased alpha-globin chain synthesis by the affected allele, or indirectly through production of hyperunstable variant alpha-globin chains. Here we describe the characterization of a 33 bp in-frame deletion within the alpha1-globin gene, in a woman with hematological findings consistent with an alpha-thal trait. The amino acids predicted to be missing as a result of the 33 bp deletion are at the end of the E helix and the EF corner of the alpha-globin protein chain, and are not normally involved in the heme contact, although it is presumed that alpha-globin chain folding and hemoglobin (Hb) formation will be disrupted. The observation of inclusion and Heinz bodies indicates the synthesis of some abnormal Hb (or globin chains). An identical mutation has been previously observed in a single case, a Canadian individual of Greek descent, indicating that it is a rare mutation, and probably of the same origin. Possible mechanisms underlying the mutation at the DNA level are discussed.  相似文献   
38.
39.
Summary. We have identified three individuals of Greek or Greek Cypriot origin with an atypical form of HbH disease characterized by a severe hypochromic microcytic anaemia associated with relatively small amounts of HbH in the peripheral blood. Molecular analysis has shown that each is a compound heterozygote for a previously described mutation affecting the poly A addition signal (AATAAA→ÁTAAG) and a previously undescribed mutation involving a T→C transition in codon 29 of the α2 gene causing a leucine→pro-line substitution. Although this mutation would be expected to produce an unstable haemoglobin and hence a haemolytic anaemia, simple heterozygotes for the α29Leu→Pro mutation have the phenotype of α-thalassaemia trait.  相似文献   
40.
The general consensus about prostatic duct adenocarcinomas is that they have a rather aggressive biological behavior. In addition, studies or reports of latent adenocarcinoma of the prostatic duct in necropsy material are scarce in the literature. We report here three cases of adenocarcinoma of the prostatic duct that were found incidentally among 39 cases of latent acinar prostate adenocarcinomas in necropsy material. We examined the morphologic and histological features of these prostatic duct adenocarcinomas, in order to better understand their biological behavior. We identified two cases of mixed ductal-acinar adenocarcinoma and one case of pure ductal adenocarcinoma. The pure form had a favorable histological differentiation, while the mixed forms had intermediate histological differentiation patterns. Invasiveness was related to both volume and histological differentiation. The finding of prostatic ductal adenocarcinomas among autopsy material, as well as some of their histological features, suggest that these tumors might have a similar biological potential as prostatic acinar cancer.  相似文献   
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