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OBJECTIVE: The aim of this study was to evaluate ventricular functions by using standard Doppler echocardiography (SDE), myocardial performance index (MPI), and pulsed wave tissue Doppler imaging (PW-TDI) in patients with ankylosing spondylitis (AS) and healthy controls. METHODS: Forty-nine AS patients (38 +/- 11 years, 25 M/24 F) and 33 controls (36 +/- 9 years, 17 M/16 F) were studied. Two-dimensional, M-Mode, SDE, PW-TDI echocardiography examinations were performed. Spinal mobility was assessed by the Bath ankylosing spondylitis metrology index (BASMI) measurement. Patients were also evaluated using the Bath ankylosing spondylitis functional index (BASFI) and the Bath ankylosing spondylitis disease activity index (BASDAI). RESULTS: Four control subjects and six AS patients met the left ventricular (LV) diastolic dysfunction (DD) criteria by using conventional Doppler echocardiography (p > 0.05). However, using PW-TDI method 22 patients in the AS group and six subjects in the control group were diagnosed to have LV DD (Em/Am < 1). Pseudonormalized pattern was present in 16 AS patients and two control subjects. Correlation analysis revealed significant moderate negative correlations between Em/Am and BASMI, age and body mass index (p < 0.05; r =-0.3, -0.6, and -0.4, respectively). No correlation was observed between Em/Am and disease duration, BASFI, BASDAI, CRP, and ESR. We could not detect any right ventricular function involvement either by conventional or by recently introduced echocardiography methods. The risk of developing LV DD was found to be 3.7 times higher in AS patients. CONCLUSION: When sensitive echocardiographic Doppler techniques such as MPI, TDI-derived MPI, and PW-TDI are utilized, DD can be detected in a significant proportion of patients with AS without cardiovascular (CV) disease which may contribute CV mortality in these patients.  相似文献   
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Impaired cochlear blood circulation has been suggested to cause sudden hearing loss. In this study, the role of factor V 1691 G-A (FV 1691 G-A), prothrombin 20210 G-A (PT 20210 G-A), methylene tetrahydrofolate reductase 677 C-T (MTHFR 677 C-T), factor V 4070 A-G (FV 4070 A-G), endothelial cell protein C receptor (EPCR) gene 23-bp insertion, and plasminogen activator inhibitor-1 (PAI-1) 4G/5G mutation was assessed. Fifty-three patients with idiopathic sudden sensorineural hearing loss and 80 individuals comprising the control group were included in this study. The frequency for FV 1691 A was 6.2% in the patient group and 3.7% in the control group, PT 20210 G-A was 1.2% in the patient group and 1.9% in the control group, and FV 4070 A-G was 7.5% in the patient group and 11.3% in the control group. The frequency of MTHFR 677 C-T was significantly higher in the patient group than in the control group, with a P value of .03. PAI-1-675 4G/5G polymorphism was found to be 71.2% and 69.8%, in the control group and the patient group, respectively. The EPCR 23-bp insertion was 0% in the control group and was found in 3 patients (3.7%), which needs further study.  相似文献   
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INTRODUCTION: High plasma levels of sEPCR lead to dysfunction of the EPCR-mediated coagulation. We have evaluated the role of EPCR A3 haplotype with its representative promoter variant 1651 C-G in a total of twenty-seven pediatric stroke patients and fifty-nine healthy subjects. MATERIALS AND METHODS: Genotyping of the A3 haplotype was performed with RFLP analysis. Plasma sEPCR levels were measured with ELISA. The mutant 1651 G allele frequency was observed to be 0.166 in the patient group. Common risk factors such as FV 1691 G-A and PT 20210 G-A mutations were also screened. RESULTS AND CONCLUSIONS: None of the patients with sEPCR levels below 100 ng/ml carried the A3 haplotype, while patients with elevated sEPCR levels carried the A3 haplotype either in a heterozygous or homozygous state. Our study confirms that there is a strong association between A3 haplotype and elevated sEPCR levels. We suggest that elevated sEPCR levels might increase the risk of stroke at pediatric age when compared to controls. Studies with large series of patients are warranted to confirm this hypothesis.  相似文献   
37.

Introduction

Thrombosis is frequently observed in Galen malformation, but propagation of thrombosis resulting in the disappearance of the aneurysmal malformation is a very rare clinical condition.

Case report

A rare case of spontaneous regression and disappearance of the vein of Galen aneurysmal malformation (VoGAM) in a pediatric patient with repeated generalized seizure, increased head circumference, and congestive heart failure is recorded. The course of regression from infancy to 8 years of age has been depicted. Radiological studies initially demonstrated VoGAM complicated by an intra-cerebral hemorrhage and hydrocephalus, which later underwent spontaneous regression. Long-term clinical and radiological follow-up is presented.

Discussion

Different conditions including hemodynamic alteration, compression of adjacent hematoma, and narrowing of related vascular structures have been described to cause thrombosis of VoGAM. The relevant literature to address possible mechanism is reviewed.
  相似文献   
38.

Background

Cavernous malformations (CMs) of the central nervous system (CNS) are angiographically occult vascular lesions that affect approximately 0.5 % of the general population, and one quarter of all CMs occurs in children.

Methods

We retrospectively analyzed demographic, clinical, radiological, management, and follow-up data of 36 pediatric patients with CMs from a single institution.

Results

The mean age of the children at first presentation and at operation was 8.7 and 9.6 years, respectively. However, a bimodal age distribution was found with peak under 4 years and above 12 years. Seizure was the most common single presenting symptom (38.9 %), and 61.1 % of patients had at least one seizure before the admission. Focal neurological deficits (410.7 %), intracranial hypertension (27.8 %), and headache (2.8 %) were the other manifestations. Acute/subacute hemorrhage was evident at presentation in 63.9 %. The patients under 6 years of age were found to have significantly more giant cavernomas (69 vs 20 %; p?=?0.011), and more overt hemorrhages (81 vs 47 %; p?=?0.065) at diagnosis than those patients above 12 years. Surgery was performed in 31 patients (32 CMs), with 26 total and 6 incomplete resections. Mean follow-up duration was 6.9?±?4.1 years. Of all patients, 63.8 % had excellent and 30.5 % had good clinical outcomes, and also 90.9 % of the epileptic patients were seizure-free (Engel Class I) at the last follow-up.

Conclusions

Younger children tend to harbor larger CMs and present with hemorrhage more frequently than older ones. Microsurgical resection should be the treatment of choice in symptomatic and accessible CMs.  相似文献   
39.
In this study, for low atomic number targets and biological compounds, an inelastic mean free path (IMFP) formula and energy straggling parameter formula are presented, being valid for low and high electron energies. In addition, calculation of the continuous slowing down approximation-range (CSDA-range) from the stopping power is also made. The IMFP and the energy straggling parameter formulae are evaluated using the generalized oscillator strength (GOS) model and the exchange correction to the inelastic differential cross section (IDCS) given by Inokuti, M., [1978. Inelastic collisions of fast charged particles with atoms and molecules--the Bethe theory revisited. Rev. Mod. Phys. 50, 23-35]. The IMFP and CSDA-range for the biological compounds C5H5N5 (adenine), C5H5N5O (guanine), C4H5N3O (cytosine), C5H6N2O2 (thymine), C20H27N7O13P2 (cytosine-guanine) and C19H26N8O13P2 (thymine-adenine) have been introduced for incident electrons in the energy range 20 eV-1 MeV. The calculated results are compared with semi-empirical results and other theoretical results, good agreement being found with experimental data and Monte Carlo (PENELOPE code) predictions. All the IMFP versus energy curves exhibit minima around 80 eV.  相似文献   
40.
Objective: The aim of the study was to evaluate the neurodevelopment outcomes of very low birth weight (VLBW) preterm infants supplemented with oral probiotics for the prevention of necrotizing enterocolitis (NEC).

Methods: A prospective follow-up study was performed in a cohort of VLBW preterm infants enrolled in a single center randomized controlled clinical trial to evaluate the efficacy of oral probiotics for the prevention of NEC. Cognitive and neuromotor developments were assessed by using the Bayley scales of infant development II. Sensory and neurological performance was evaluated by standard techniques. The primary outcome was neurodevelopmental impairment at 18–24 months’ corrected age.

Results: A total of 400 infants completed the trial protocol. Of the 370 infants eligible for follow-up, 249 infants (124 in the probiotics group and 125 in the control group) were evaluated. There was no significant difference in any of the neurodevelopmental and sensory outcomes between the two groups.

Conclusion: Oral probiotic given to VLBW infants to reduce the incidense and severity of NEC started with the first feed did not affect neuromotor, neurosensory and cognitive outcomes at 18–24 months’ corrected age.  相似文献   

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