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91.
Cardiac papillary fibroelastoma (CPF) is a rare cardiac neoplasm predominantly affecting the cardiac valves. Although it is most commonly an incidental finding, it can result in life-threatening complications, such as coronary and cerebral embolism, acute valvular dysfunction, and sudden death. In this report, we describe a case of a patient with aortic valve papillary fibroelastoma, which presented with sudden vision loss due to branch retinal artery occlusion. To the best of our knowledge, this is the third case of CPF-related retinal artery embolism in English literature.  相似文献   
92.
Chemical penetration enhancers (CPEs) are present in a large number of transdermal, dermatological, and cosmetic products to aid dermal absorption of curatives and aesthetics. This wide spectrum of use is based on only a handful of molecules, the majority of which belong to three to four typical chemical functionalities, sporadically introduced as CPEs in the last 50 years. Using >100 CPEs representing several chemical functionalities, we report on the fundamental mechanisms that determine the barrier disruption potential of CPEs and skin safety in their presence. Fourier transform infrared spectroscopy studies revealed that regardless of their chemical make-up, CPEs perturb the skin barrier via extraction or fluidization of lipid bilayers. Irritation response of CPEs, on the other hand, correlated with the denaturation of stratum corneum proteins, making it feasible to use protein conformation changes to map CPE safety in vitro. Most interestingly, the understanding of underlying molecular forces responsible for CPE safety and potency reveals inherent constraints that limit CPE performance. Reengineering this knowledge back into molecular structure, we designed >300 potential CPEs. These molecules were screened in silico and subsequently tested in vitro for molecular delivery. These molecules significantly broaden the repertoire of CPEs that can aid the design of optimized transdermal, dermatological, and cosmetic formulations in the future.  相似文献   
93.
OBJECTIVE: Postural phenomena, cardiac arrhythmias and autonomic dysfunction are responsible for presyncope and syncope in patients with mitral valve prolapse (MVP). In this study, arrhythmia and vasovagal syncope incidence were investigated in children with MVP. METHODS: Between April 2005 and December 2006, 37 children with MVP and 26 healthy children were evaluated.Telecardiography, electrocardiography (ECG), echocardiography, Holter monitoring, exercise test and head-up tilt test were performed. RESULTS: The MVP group consisted of 19 boys and 18 girls with a mean age of 11.8 years. The control group was similar with respect to age and gender. Telecardiography, ECG, Holter monitoring, exercise test and QTc of all children were within normal limits.There was a statistically significant difference between the two groups in terms of QT dispersion. The tilt table test was positive in 11 of 37 (29.7%) children with MVP and in 1 of 26 (3.8%) normal healthy children. This difference was statistically significant (P < 0.01). CONCLUSION: Arrhythmia and syncope frequency was found to be higher in children with MVP than in the normal population. The risk of vasovagal syncope indicated by a positive tilt test was found to be increased in children with MVP. Therefore, patients and families must be informed about the conditions that may predispose to vasovagal syncope and caution should be recommended in these patients.  相似文献   
94.
AIM/BACKGROUND: Achalasia may be associated with extraesophageal dysmotility. However, this relation is still poorly understood. In the present study, we used noninvasive real-time ultrasonography to examine the motility function of the gallbladder in the patients with achalasia. MATERIALS AND METHODS: Thirty-three achalasic patients and 33 healthy volunteers were included in the study. All subjects were investigated after 12 hours of fasting and 30 minutes after a standard test meal. Premeal and postmeal gallbladder volumes were used for calculation of the ejection fraction of the gallbladder and fasting gallbladder volume. RESULTS: The mean fasting volume (18.52+/-1.45 vs. 24.63+/-1.84 cm; P<0.05) and ejection fractions of gallbladder (35.84+/-4.12 vs. 54.47+/-2.47; P<0.05) in the patients with achalasia were lower than the control group. CONCLUSIONS: Such a finding may confirm the possible extraesophageal extension of primary achalasia. Achalasic patients have smaller gallbladders than do others. It could be speculated that it is congenital and/or achalasic patients' gallbladder has incomplete relaxation (as in the lower esophageal sphincter of the achalasia).  相似文献   
95.
Thalidomide is shown to be an effective treatment for mucocutaneous symptoms of Behcet's disease (BD). In this study, the effects of thalidomide on peripheral blood mononuclear cells were investigated ex vivo. In an open prospective study, ten patients were given 200 mg/day thalidomide for 12 weeks and cluster of differentiation 4 (CD4), CD8, CD11a, CD11b, CD16, CD18, CD28, CD44, CD45RO, CD45RA, CD56, CD120a and γδ+ T cells were analysed with flow cytometry at 0, 3, 7, 30 and 90 days. Two patients were excluded from the analysis for attacks of uveitis within the first 2 weeks. At day 7, tumour necrosis factor-α (TNF-α) receptor+ (CD120a; 12% vs 5%), CD8/CD11b+ (12% vs 6%) and CD16/CD56+ (16% vs 9%) cells decreased in BD patients compared to day 0. On the other hand, CD4+CD45RO+ T cells (24% vs 34%) at day 30 and γδ+ T cells (11% vs 21%) at day 90 increased after treatment. These results suggest that thalidomide tends to decrease TNF-α receptor levels, CD8/CD11b+ T cells and natural killer cells in early treatment and increases CD4+CD45RO+ memory T and γδ+ T cells later in BD.  相似文献   
96.
Background Patients with Turner syndrome (TS) are treated with GH to increase adult height. Although it is well established that GH promotes longitudinal bone growth, the effects of GH treatment on bone density are less clear. Objective To determine how GH treatment affects trabecular bone mineral density (BMD) in girls with TS at prepubertal ages in a prospective multicentre study. Patients and method Twenty‐two patients with TS in the prepubertal period with a mean age of 9·8 ± 2·5 (range 3·6–12·8) years were included in the study. All girls with TS underwent measurement of areal BMD using dual‐energy X‐ray absorptiometry (DXA) to obtain pretreatment anteroposterior (AP) lumbar spine values at L1–L4. Patients received GH (Genotropin) subcutaneously for 1 year at a dose of 0·05 mg/kg/day. Height and weight were measured at 3‐monthly intervals. The AP lumbar spine areal BMD was remeasured using the same technique after 1 year of treatment. Lumbar spine BMD Z‐scores and volumetric BMD (vBMD) Z‐scores were calculated using national standards. Results The height SDS of our cases showed a significant increase with GH therapy. The pretreatment lumbar spine (L1–L4) BMD Z‐score was –1·2 ± 1·2 SD and the vBMD Z‐score was –0·8 ± 1·6 SD. There were no significant changes in these values after 1 year of GH treatment. Prepubertal TS girls more than 11 years of age had lower vBMD Z‐scores (–1·7 ± 1·7 SD) than the girls aged less than 11 (–0·1 ± 1·0 SD) (P < 0·05) at the onset of therapy. No significant changes were observed in these values after 1 year of GH therapy. Conclusions Osteopaenia becomes apparent in prepubertal TS patients as they reach pubertal age. BMD evaluation may be necessary in these prepubertal TS girls at diagnosis. Short‐term GH therapy in these TS patients does not have a significant effect on bone density when measured at a site with a predominance of trabecular bone.  相似文献   
97.
This study aimed to determine whether plasma levels of tumor necrosis factor-α (TNF-α) and soluble TNF receptor (sTNF-R) increases in rheumatic mitral stenosis (MS) patients with sinus rhythm and to examine the effect of percutaneous mitral balloon valvuloplasty (PMBV) on these parameters. Twenty-six patients with MS and sinus rhythm (study group, 20 female, mean age 33 ± 8 years), who were scheduled for PMBV, and a well-matched control group consisting of 21 healthy volunteers (15 female, mean age 35 ± 6 years) were enrolled in the study. Tumor necrosis factor-α and sTNF-R levels were compared between study patients and controls, and between peripheral and left atrium (LA) blood. Changes in TNF α and sTNF-R levels 24 h and 4 weeks after PMBV were analyzed. Significantly higher baseline TNF-α and sTNF-R levels were noted in the study group. In the study group, TNF-α and its receptors were also found to be higher in LA blood than in baseline peripheral blood. After PMBV, mitral valve area (MVA) increased and transmitral pressure gradient decreased significantly. At the 24th hour after PMBV, the TNF-α level decreased from 29.61 ± 12.22 pg/ml to 22.42 ± 8.81 pg/ml (P < 0.0001) and at the 4th week, from 22.42 ± 8.81 pg/ml to 18.92 ± 7.37 pg/ml (P < 0.0001). Similar reductions were observed in the sTNF-R level. Regression analysis between the difference in sTNF-R level measured 24 h after and before PMBV and the difference in MVA measured 24 h after and before PMBV showed a significant direct relationship between these variables. This study suggests that isolated rheumatic MS without atrial fibrillation is accompanied by increased TNF-α and sTNF-R level. The successful PMBV establishes a significant reduction in TNF-α and its receptors, probably due to improved postprocedural hemodynamic parameters.  相似文献   
98.
Despite their proven efficacy at reducing mortality in selected patients, implantable cardioverter-defibrillators have some proarrhythmic effects. In this report, we present a case of a patient with recurrent ventricular tachycardia degeneration to ventricular fibrillation by appropriate low-energy implantable cardioverter-defibrillator shocks.  相似文献   
99.
Increased oxidative stress and impaired anti-oxidant defense have been suggested as contributory factors for initiation and progression of complications in diabetes mellitus. Aging itself has been shown to be along with increased oxidative stress and lower anti-oxidant defense. We aimed at investigating oxidative stress and anti-oxidant enzymes in 61 elderly subjects. Fifteen healthy individuals (group 1, mean age 72.2 +/- 5.13), 13 glucose intolerant patients (group 2, mean age 71.7 +/- 4.9), 19 patients with type 2 diabetes mellitus (T2DM) without any complication (group 3, mean age 70.0 +/- 6.0), and 14 patients with T2DM with at least one complication (group 4, mean age 69.8 +/- 4.7) were included in the study. Whilst plasma levels for malondialdehyde (MDAP) and erythrocyte malondialdehyde (MDAE) were measured as markers of oxidative stress, activity of erythrocyte superoxide dismutase (SOD), glutathion peroxidase (GSH-Px), and catalase (CAT) were taken as markers of oxidative defense system. MDAP level was significantly elevated in group 4 (P = 0.001). MDAE was elevated in patients with T2DM, particularly in group 4, however, the difference between the groups was of borderline significance (P = 0.07). Whilst CAT was elevated in groups 3 and 4 compared to control subjects (P = 0.025 and 0.002, respectively), no difference was found for SOD between the groups. GSH-Px activity was found to be increased in groups 2, 3 and 4, it did not reach statistical significance (P = 0.106). There were significant correlations between CAT and MDAE (P < 0.0001, r = 0.056) and MDAP (P = 0.016, r = 0.306). These results suggest that there was an increased oxidative stress in elderly diabetics, however, this is not due to reduced erythrocyte antioxidant defense potential but, rather, increased free radical production possibly due to hyperglycemia.  相似文献   
100.
We have shown that smoking impacts bronchial airway gene expression and that heterogeneity in this response associates with smoking-related disease risk. In this study, we sought to determine whether microRNAs (miRNAs) play a role in regulating the airway gene expression response to smoking. We examined whole-genome miRNA and mRNA expression in bronchial airway epithelium from current and never smokers (n = 20) and found 28 miRNAs to be differentially expressed (P < 0.05) with the majority being down-regulated in smokers. We further identified a number of mRNAs whose expression level is highly inversely correlated with miRNA expression in vivo. Many of these mRNAs contain potential binding sites for the differentially expressed miRNAs in their 3′-untranslated region (UTR) and are themselves affected by smoking. We found that either increasing or decreasing the levels of mir-218 (a miRNA that is strongly affected by smoking) in both primary bronchial epithelial cells and H1299 cells was sufficient to cause a corresponding decrease or increase in the expression of predicted mir-218 mRNA targets, respectively. Further, mir-218 expression is reduced in primary bronchial epithelium exposed to cigarette smoke condensate (CSC), and alteration of mir-218 levels in these cells diminishes the induction of the predicted mir-218 target MAFG in response to CSC. These data indicate that mir-218 levels modulate the airway epithelial gene expression response to cigarette smoke and support a role for miRNAs in regulating host response to environmental toxins.  相似文献   
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