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991.
Abdolrazagh Kiani Sima Rafieyian Shahla Roodpeyma Maryam Sefidgarnia 《Iranian journal of pediatrics.》2011,21(2):220-224
Objective
QT dispersion (QTd) has been proposed as a marker of ventricular repolarization inhomogeneity and several investigations have proved the relationship between it and cardiac ischemia, ventricular arrhythmia and sudden cardiac death. The aim of this study was to assess the relation between coronary artery involvement and QTd, and QTc dispersion (QTcd) in the acute phase of Kawasaki disease (KD).Methods
We studied 65 patients with acute KD. Patients were divided into 3 groups. Group one consisted of 48 patients without coronary artery involvement. Group two comprised 13 patients with small to medium size aneurysm. In Group three there were 4 patients with giant aneurysm or multiple small to medium size aneurysms or thrombosis in coronary arteries. For each patient 12 lead electrocardiography was obtained, and QT, QTc, QTd, QTcd, and RR interval were calculated.Findings
There were 40 males and 25 females with a mean age of 41.4±31.1 months. There was no significant difference in QT, QTc, RR measurements between 3 groups. QTd was greater in group 3 versus group 1 and 2, but the difference was not statistically significant (P=0.06). QTcd was significantly greater in group 3 than in groups 1 and 2 (75.02±11.53 ms versus 46.82±15.39 ms and 48.88±10. 55 ms respectively (P = 0.04). The sensitivity of QTcd ≥60 ms to detect the patients with severe coronary arteries involvement was 100%, the specificity was 93.4%, positive predictive value was 50%, negative predictive value was 100%, and accuracy was 93.8%.Conclusion
QTcd can be used as a predictive factor for diagnosis of severe coronary arteries involvement in the acute phase of KD. 相似文献992.
Carmelann Zintz Karin Bok Ester Parada Myra Barnes-Eley Tamas Berke Mary A Staat Parvin Azimi Xi Jiang David O Matson 《Infection, genetics and evolution》2005,5(3):281-290
Human calicivirus was the first recognized viral agent causing gastroenteritis in humans. Norovirus (NV) and Sapovirus (SV), two genera within the Caliciviridae family, cause epidemic and endemic acute gastroenteritis in children and adults. The role of these viruses as a cause of sporadic acute gastroenteritis in young children requiring hospitalization is not well established. The aim of this study was to assess the prevalence and genetic diversity of caliciviruses among children hospitalized with symptoms of acute gastroenteritis. Stool samples were collected over 2 years from symptomatic children (N=1840) up to 5 years of age at three pediatric hospitals in the US. Overall, 156 (8.5%) samples were CV-positive, 131 (7.1%) confirmed by sequencing to be NV and 25 (1.4%) confirmed to be SV. Sequences of RT-PCR-amplified polymerase gene segments were analyzed using distance, maximum likelihood and parsimony algorithms. Phylogenetic analysis of 97 NV sequences showed that seven strains were in genogroup I, 86 strains were in genogroup II and four strains were not in genogroup I, II, or III, likely representing three new NV genogroups IV, VI and VII. Genogroup I and genogroup II strains were in 12 new genetic clusters, three in genogroup I and nine in genogroup II. Within genogroups I and II, most (98%) NV strains were in genetic clusters with no known prototype in GenBank. Phylogenetic analysis of 24 SV strains showed that half grouped with the London/92 strain in one genogroup and the remainder in three other proposed genogroups, one novel. In conclusion, NV and SV were frequent causes of hospitalization for acute gastroenteritis in young children and infecting strains were highly diverse, including newly recognized genogroups and genetic clusters within known genogroups. 相似文献
993.
Sofie Van Cauter Frederik De Keyzer Diana M. Sima Anca Croitor Sava Felice D'Arco Jelle Veraart Ronald R. Peeters Alexander Leemans Stefaan Van Gool Guido Wilms Philippe Demaerel Sabine Van Huffel Stefan Sunaert Uwe Himmelreich 《Neuro-oncology》2014,16(7):1010-1021
Background
We assessed the diagnostic accuracy of diffusion kurtosis imaging (DKI), dynamic susceptibility-weighted contrast-enhanced (DSC) MRI, and short echo time chemical shift imaging (CSI) for grading gliomas.Methods
In this prospective study, 35 patients with cerebral gliomas underwent DKI, DSC, and CSI on a 3 T MR scanner. Diffusion parameters were mean diffusivity (MD), fractional anisotropy, and mean kurtosis (MK). Perfusion parameters were mean relative regional cerebral blood volume (rrCBV), mean relative regional cerebral blood flow (rrCBF), mean transit time, and relative decrease ratio (rDR). The diffusion and perfusion parameters along with 12 CSI metabolite ratios were compared among 22 high-grade gliomas and 14 low-grade gliomas (Mann–Whitney U-test, P < .05). Classification accuracy was determined with a linear discriminant analysis for each MR modality independently. Furthermore, the performance of a multimodal analysis is reported, using a decision-tree rule combining the statistically significant DKI, DSC-MRI, and CSI parameters with the lowest P-value. The proposed classifiers were validated on a set of subsequently acquired data from 19 clinical patients.Results
Statistically significant differences among tumor grades were shown for MK, MD, mean rrCBV, mean rrCBF, rDR, lipids over total choline, lipids over creatine, sum of myo-inositol, and sum of creatine. DSC-MRI proved to be the modality with the best performance when comparing modalities individually, while the multimodal decision tree proved to be most accurate in predicting tumor grade, with a performance of 86%.Conclusions
Combining information from DKI, DSC-MRI, and CSI increases diagnostic accuracy to differentiate low- from high-grade gliomas, possibly providing diagnosis for the individual patient. 相似文献994.
Onset of natural killer cell lymphomas in transgenic mice carrying a truncated HMGI-C gene by the chronic stimulation of the IL-2 and IL-15 pathway 总被引:8,自引:0,他引:8
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Gustavo Baldassarre Monica Fedele Sabrina Battista Andrea Vecchione Andres J. P. Klein-Szanto Massimo Santoro Thomas A. Waldmann Nazli Azimi Carlo M. Croce Alfredo Fusco 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(14):7970-7975
Rearrangements of the high mobility group protein I-C (HMGI-C) gene, consisting in the loss of the carboxyl-terminal tail, have been frequently detected in benign human tumors of mesenchymal origin. We have previously demonstrated that transgenic (TG) mice carrying a truncated HMGI-C construct (HMGI-C/T) exhibit a giant phenotype together with a predominantly abdominal/pelvic lipomatosis. Here, we report that HMGI-C/T TG mice develop natural killer (NK)-T/NK cell lymphomas starting from 12 months of age. We found an increased expression of IL-2 and IL-15 proteins and their receptors in these lymphomas, and we demonstrate that HMGI-C/T protein positively regulates their expression in vitro. Therefore, the HMGI-C/T-mediated chronic stimulation of the IL-2/IL-15 pathway could be responsible for the onset of NK-T/NK cell lymphomas in HMGI-C/T TG mice. 相似文献
995.
Anders A.F. Sima Weixian Zhang Christian W. Kreipke José A. Rafols William H. Hoffman 《The review of diabetic studies : RDS》2009,6(1):37-42
Encephalopathy is an increasingly recognized complication of type 1 diabetes. The underlying mechanisms are not well understood, although insulin deficiency has been implicated. The spontaneously diabetic BB/Wor-rat develops neuro-behavioral deficits and neuronal cell death in hippocampus and frontal cortex, which can be prevented by insulinomimetic C-peptide. Here we examined whether contributing factors such as activation of innate immune mediators are responsive to C-peptide replacement. Seven-month diabetic BB/Wor-rats and those treated with full C-peptide replacement were compared to age-matched control rats. Hippocampi of diabetic rats showed upregulation of RAGE and NF-κB, the former being localized to proliferating astrocytes. These changes were associated with increased expression of TNF-α, IL-1β, IL-2 and IL-6 in hippocampi of diabetic rats. Full C-peptide replacement, which did not induce hyperglycemia, resulted in significant prevention of upregulation of RAGE expression, activation of NF-κB and activation of pro-inflammatory factors. In conclusion, impaired insulin activity is associated with upregulation of RAGE and pro-inflammatory factors, and these are likely to contribute to previously described oxidative and apoptotic neuronal cell death. Replacement of insulinomimetic C-peptide significantly prevents this cascade of events. 相似文献
996.
Sima Pavlovic MD Karl Georg Schmidt MD Zoran Tomic MD Miroslav Dzinic MD 《Clinical & experimental ophthalmology》1998,26(3):241-246
Purpose: To identify both the clinical features of eyes suffering penetrating ocular injury with intra-ocular foreign bodies (FB) impacting or embedded in the retina and the results of surgical outcome and complication rates. Methods: Thirty-eight consecutive cases of penetrating ocular injuries with intra-ocular FB impacting or embedded in the retina were retrospectively analysed. Results: The FB were metallic in 30 eyes (78.9%; 19 ferromagnetic) and were non-metallic in eight eyes (21.1%). Magnetic extraction was performed in 17 cases (44.7%) and instrumental extraction was performed in 21 cases (55.3%). In two cases, pars plana vitrectomy and FB removal was combined with penetrating keratoplasty, temporary keratoprosthesis and anterior segment reconstruction because of severe explosive injury to the eye. At the final postoperative examination, 32 eyes (84.2%) had completely attached retinas. Visual acuity (VA) improved postoperatively in 18 eyes (47.4%). A final VA of 0.5 or better was achieved in nine of 23 eyes (39.1%) with FB in the peripheral retina and in one of 15 eyes (6.7%) with posterior pole and/or optic nerve head involvement. There was no difference in the final VA regarding the time elapsed between trauma and the removal of the FB. Conclusion: The late anatomical and functional outcome in eyes with penetrating ocular injury and FB impacting or embedded in the retina is mostly uncertain, despite immediate and complex surgery. Final anatomical and functional outcome in the present study was influenced by location and extent of the initial damage to the posterior pole. The time that had elapsed between trauma and removal of the FB did not influence final visual function. 相似文献
997.
Parvin Mirmiran Fatemeh Mohammadi Sima Allahverdian Fereidoun Azizi 《Nutrition Research》2002,22(12):61-1375
This study was conducted to assess the association of educational level and marital status with dietary intake, obesity and other cardiovascular risk factors. 733 subjects, 408 women and 325 men, aged between 20-60 years, were randomly selected from the participants of the Tehran Lipid and Glucose Study. Data on educational level, and marital status were obtained by a questionnaire. Following measurement of weight, height, waist and hip according to standard protocol, body mass index (BMI) and waist to hip ratio (WHR) were calculated. Dietary intake was assessed by completing two 24-hour dietary recalls during face to face interviews. Serum cholesterol, triglycerides levels, and HDL cholesterol were measured after 12-14 hours fasting. Subjects were divided into four groups based on educational levels: illiterate or low literacy, intermediary school, high school and university graduates. Adjusted for age, increases in triglycerides levels in men with high educational levels were observed. In women with different educational levels, none of the studied variables differed. In married men total energy intake (3001 ± 625 vs. 2905 ± 543 Kcal/d, P < 0.05) and iron intake (29.0±8.1 vs. 28.1± 10 mg/d, P < 0.05) were significantly higher than in single men. BMI and WHR in single women were lower than in married ones (P < 0.05) and HDL-cholesterol was higher in single men (P < 0.05) and women (P < 0.01). We concluded that educational level and marital status has an association with BMI, WHR, serum lipid levels and dietary intake, in men and women. 相似文献
998.
Sid Gilman Anders A. F. Sima Larry Junck Karen J. Kluin Robert A. Koeppe Mary E. Lohman Roderick Little 《Annals of neurology》1996,39(2):241-255
Spinocerebellar ataxia type 1 (SCA1) is a dominantly inherited progressive neurological disorder characterized by neuronal degeneration and reactive gliosis in the cerebellum, brainstem, spinocerebellar tracts, and dorsal columns. Multiple system atrophy is a sporadic progressive neurological disorder with degeneration and gliosis in the basal ganglia, cerebellum, brainstem, and spinal autonomic nuclei, and with argyrophilic glial cytoplasmic inclusions. We describe 4 members of a family with the SCAl mutation and a dominantly inherited progressive ataxia in which autopsy examination of 1 member showed neuropathological changes typical of multiple system atrophy, including glial cytoplasmic inclusions. In this patient, magnetic resonance imaging revealed marked brainstem and cerebellar volume loss and mild supratentorial generalized volume loss. Positron emission tomography with [18F]fluorodeoxyglucose revealed widespread hypometabolism in a pattern found in sporadic multiple system atrophy and not in dominantly inherited olivopontocerebellar atrophy. Positron emission tomography with [llC]flumazenil revealed normal benzodiazepine receptor distribution volumes, similar to those seen in sporadic multiple system atrophy. Two other family members still living had similar changes in the imaging studies. The findings in this family suggest that the SCAl gene mutation can result in a disorder similar to multiple system atrophy, both clinically and neuropathologically. 相似文献
999.
1000.
Pippa Oakeshott Sally Kerry Sima Hay Philip Hay 《The British journal of general practice》2004,54(499):119-122
BACKGROUND: Preterm birth before 37 weeks' gestation is associated with 70% of perinatal morbidity and nearly half of long-term neurological morbidity. Hospital-based studies have shown that bacterial vaginosis is associated with preterm birth. AIM: To estimate the relative risk of preterm birth in women with and without bacterial vaginosis, detected by self-administered vaginal swab at < 10 weeks' gestation. DESIGN: Prospective cohort study. SETTING: Thirty-two general practices and five family planning clinics in South London. PARTICIPANTS: A total of 1216 women with bacterial vaginosis status established before 10 weeks' gestation, by analysis of Gram stained vaginal smears by two independent observers. METHOD: All women who did not miscarry or have a termination of pregnancy before 16 weeks' gestation were sent a brief confidential questionnaire at 16 weeks and at term asking about pregnancy outcome. Data on non-responders were obtained by searches of hospital and general practice records and by telephone calls to patients. RESULTS: Ascertainment was 87% (937/1072). The mean age of the women was 31 years. Thirteen per cent (122/925) had bacterial vaginosis and 5% (44/897) had a spontaneous preterm birth. The relative risk (RR) of preterm birth in women with bacterial vaginosis was 0.9 (95% confidence interval [CI] = 0.4 to 2.2). However, bacterial vaginosis was associated with late miscarriage at 13-23 weeks (R = 4.0, 95%CI = 1.3 to 12.1). Preterm birth was not associated with previous preterm birth, black ethnicity, age < 20 years, low social class, single marital status, or chlamydial infection. However, it was more common in women who reported smoking in pregnancy (RR = 2.9, 95% CI = 1.5 to 5.5). Of 867 responders, 552 (64%) said that providing a vaginal swab was at least as easy as providing a urine specimen. CONCLUSIONS: In this low-risk community-based cohort, bacterial vaginosis was not a strong risk factor for preterm birth. 相似文献