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41.
The advances in neuroimaging have improved clinicoanatomic correlations in patients with stroke. Junctional infarct is a distinct term, used to describe border zone infarcts of the posterior fossa. We presented computed tomography (CT) and magnetic resonance imaging (MRI) findings in a rare case of bilateral symmetrical junctional infarcts between the superior cerebellar artery (SCA) and posterior inferior cerebellar artery (PICA) territories. In addition to precise knowledge of arterial territories required to achieve accurate localization of ischemic lesions on CT and MRI, the radiologist must also be aware of radiologic features and geographic territories of cerebellar arteries and their junctional infarctions.  相似文献   
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Objective.

Urotensin II is a potent vasoactive peptide that has been implicated in the pathophysiology of many diseases. There is no study reporting the role and level of this peptide in recipients of kidney transplant. So we aimed to study the plasma levels of urotensin II in this group of patients.

Methods.

Plasma urotensin II levels were analyzed in 110 subjects, who were divided into three groups: group 1 (35 kidney transplant recipients), group 2 (36 patients with chronic kidney disease), and group 3 (39 healthy controls).

Results.

Analysis of logarithmic transformation of urotensin II, i.e. log (urotensin II × 1000) levels, with a one-way analysis of variance yielded a P value of 0.001. Post-hoc analysis showed significantly higher log (urotensin II × 1000) levels in group 1 than groups 2 and 3 (P = 0.001 and 0.017, respectively). One of the important features of the subjects of this group was that they were taking immunosuppressive drugs because of renal transplantation.

Conclusions.

High urotensin II levels in recipients of kidney transplants could be drug-related (immunosuppressive drugs) and may be of practical importance that may be used to improve the long-term outcome of the patients.  相似文献   
45.
OBJECTIVE: To compare various graft materials in the rabbit model, including autologous cartilage, dermal tissue, fat, and AlloDerm (a cadaver-derived material). METHODS: Twenty-five New Zealand white rabbits were used. Equally sized autogenous (fat, fascia, cartilage, and dermal) grafts and AlloDerm were implanted into subcutaneous dorsal pockets on the rabbits. Animals were killed 1, 2, 3, and 4 months after surgery. The grafts were examined microscopically for thickness, resorption, fibrosis, neovascularization, inflammation, eosinophilia, and the presence of multinucleated giant cells or microcysts. RESULTS: The cartilage grafts revealed excellent viability with no resorption. The fascial grafts showed negligible volume loss. The dermal grafts developed epidermoid cysts. The AlloDerm grafts demonstrated graft thickening at 1 month and total resorption at 3 and 4 months. The fat grafts demonstrated 30% to 60% partial resorption. CONCLUSIONS: The major disadvantage of using an autogenous fat graft was partial resorption, whereas cyst formation was observed with dermal grafts. AlloDerm caused tissue reaction and resorption. The best graft material was cartilage, with a low absorption rate, good biocompatibility, and minimal tissue reaction or fibrosis, followed by fascia, with a minimal shrinkage capacity and tissue reaction.  相似文献   
46.
BACKGROUND: Cardiac involvement in scleroderma is a poor prognostic sign and is usually underdiagnosed, particularly in asymptomatic patient. This paper focuses on QT dynamicity and heart rate variability (HRV) in patients with scleroderma and controls in an attempt to investigate the cardiac autonomic system and ventricular repolarization. METHODS: Sixty patients with scleroderma and 30 age- and sex-matched healthy controls who had no cardiovascular risk factors were included in this study. All patients and the controls underwent a 24-hour holter recording as well as a transthoracic echocardiography. HRV and QT dynamicity parameters were calculated. RESULTS: In HRV analysis, autonomic balance was changed in favor of the sympathetic system in patients with diffuse scleroderma. In QT dynamicity analysis, QT/RR slopes were significantly steeper in patients with diffuse scleroderma compared to patients with limited scleroderma and controls (QTapex/RR: 0.24 +/- 0.16, 0.15 +/- 0.03, 0.14 +/- 0.03 respectively p < 0.001; QTend/RR: 0.26 +/- 0.17, 0.14 +/- 0.04, 0.13 +/- 0.05, respectively p < 0.001). CONCLUSIONS: Patients with diffuse scleroderma may have asymptomatic cardiac repolarization abnormalities and autonomic dysfunction. Our results may indicate that QT dynamicity and HRV can be useful noninvasive methods that may detect impaired state of autonomic balance and cardiac repolarization in patients with diffuse scleroderma.  相似文献   
47.
Systemic scleroderma is a disease that is characterized by excessive fibroblastic activity and collagen deposition in various organs, including the heart. We sought to evaluate the limits of biventricular function as derived noninvasively from pulsed-wave tissue Doppler imaging (TDI) of tricuspid and mitral annular motion in patients who had scleroderma.We enrolled 24 patients with scleroderma (study group; mean age, 49 ± 11 yr; 20 women) and 24 healthy participants (control group; mean age, 51 ± 9 yr; 19 women). Persons with cardiovascular risk factors were excluded. We obtained images by conventional echocardiography and by pulsed-wave TDI, measuring the respective peak systolic velocities (S, Sm) and peak early (E, Em) and late (A, Am) diastolic velocities. Mean Sm, mean Em, and mean Am were averages of the 4 measured sites (anterior, inferior, lateral, and septal). We calculated noninvasive estimates of left ventricular (LV) filling pressure by dividing E velocities (from the mitral inflow) by Em velocities (E/Em ratios).Biventricular regional Sm, regional LV myocardial Em, and ratios of myocardial Em/atrial component velocity (Em/Am) for the LV, and mean Sm, mean Em, and mean Em/mean Am ratios for the LV were significantly lower in the study group. The E/Em ratio was higher in the study group (7.3 ± 2.6 vs 5.2 ± 1.0, P = 0.01). Global LV systolic and diastolic function did not differ between the groups.Tissue Doppler imaging complements conventional echocardiography in detecting subclinical biventricular impairment in patients with scleroderma who have normal global measurements.Key words: Case-control studies, diastole/physiology, echocardiography/methods, heart diseases/ultrasonography, heart ventricles/ultrasonography, scleroderma, systemic/complications/diagnosis/physiopathology, sensitivity and specificity, systole/physiology, ultrasonography, Doppler, pulsed/methods, ventricular dysfunction/ultrasonographySystemic sclerosis is a connective-tissue disease that is clinically characterized by variable involvement of the skin and the visceral organs.1 Involvement of the heart is one of the most frequent complications that has been reported in several clinical investigations and autopsy studies.1–3 When scleroderma involves the heart, fibrosis due to collagen deposition replaces damaged muscle cells with fibrous ones, which leads to atrial and ventricular arrhythmias, conduction disturbances, and right ventricular (RV) and left ventricular (LV) systolic and diastolic dysfunction.4 Cardiac involvement can exist without symptoms; once it becomes clinically apparent, the affected patient''s prognosis is poor.5–7Pulsed-wave tissue Doppler imaging (PW TDI) is a recently developed ultrasonographic technique that enables quantitative analysis of global and regional myocardial function. It has been shown that early diagnosis of ventricular dysfunction is possible by the use of newer techniques such as PW TDI.8,9 Previous investigators who used tissue Doppler echocardiography reported reduced systolic myocardial function of the LV10 and significant improvement after patients were treated with nifedipine,11 while others12 detected no alteration in the systolic function of patients who had scleroderma. Several investigators have reported LV diastolic dysfunction after using conventional echocardiography or TDI.12–15 Right ventricular diastolic impairment has also been reported.15–17 In our study, we sought to investigate RV and LV function by both conventional echocardiography and PW TDI.  相似文献   
48.
Interleukin 33 (IL-33) is a cytokine belonging to the IL-1 superfamily. Soluble ST2 (sST2) binds to IL-33 and by functioning as trap receptor inhibits signal sending to Th2 via transmembrane ST2. Because Th2-type cytokines play an important role in fibrosis, the aim of this study is to determine whether sST2 can be used as a marker of fibrosis in chronic hepatitis B (CHB) patients or not.The study included 19 healthy controls, 54 patients with CHB, and 14 patients with cirrhosis because of CHB. The aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4) scores also calculated, and correlations between liver biopsies, sST2 levels, and these scores were analyzed in CHB and cirrhosis patients.The sST2 levels in patients with CHB were significantly higher than those in the control group subjects (median: 1133 pg/mL vs 762.5 pg/mL, respectively [P = 0.035]). In CHB patients, the METAVIR fibrosis score (stages from 0 to 4) showed a moderate correlation with serum sST2 level (r = 0.396, P = 0.004) and a weak correlation with FIB-4 score (r = 0.359, P = 0.008), but no correlation with APRI score (r = 0.253, P = 0.06). The under the curve value of serum sST2 was 0.68, and its prediction of significant fibrosis (METAVIR score ≥2) in values >674 pg/mL had a sensitivity of 91.7% and specificity of 40% (P = 0.009). According to multiple logistic regression analysis, only METAVIR fibrosis stage was found to be an independent predictor of serum sST2 elevation in CHB patients (P = 0.04).The sST2 level can be used for differentiating significant fibrosis from mild fibrosis in CHB patients. However, the efficacy of this marker should be verified by larger studies in the future.  相似文献   
49.
Anaplastic large-cell lymphoma (ALCL) is a rare T-cell lymphoma and typically is seen in children and young adults. Primary bone infiltration of ALCL is exceedingly rare. Herein we report ALCL of bone in a pregnant admitted with symmetric polyarthritis. Magnetic resonance imaging of the pelvis revealed soft tissue component of that destructive mass lesion on the right iliac crest after delivery. Excisional biopsy from the destructive mass showed anaplastic large cell lymphoma (CD 30 was positive and ALK negative). The patient was treated with combination chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) every 4 weeks. After the third cycle of chemotherapy, a marked improvement of her arthritis and right iliac pain was noted.  相似文献   
50.

Background

In recent years, the optimal location for noninvasive mechanical ventilation (NIMV) has been a matter of debate. Our aim was to detect the effectiveness of NIMV in acute hypercapnic respiratory failure (AHRF) in respiratory ward and factors associated with failure.

Methods

69 patients treated with NIMV in respiratory ward were prospectively evaluated. The success of NIMV was defined as absence of need for intensive care unit (ICU) transfer with patient's dishcarge from hospital (group 1), failure of NIMV was defined as need for ICU transfer (group 2).

Results

The mean age was significantly higher in group 2. The cause of respiratory failure was COPD in 51 patients, obesity-hypoventilation syndrome in 14 and kyphoscoliosis in 4 patients. NIMV was successful in 55 patients and unsuccessful in 14. There was no significant difference between the two groups for pretreatment pH, PaCO2 and PaO2/FiO2. After 1 h and 3 h of NIMV there was significant improvement in group 1. After 3 h of NIMV, in group 1 respiratory rate was significantly decreased. The pretreatment APACHE II score, respiratory rate, frequency of pneumoniae, associated complication and comorbid disease was significantly higher in group 2. The success rate was higher in patients with good compliance to NIMV.

Conclusion

NIMV can be succesfully applied in patients with AHRF in respiratory ward. The associated factors with NIMV failure are absence of early improvement in blood gases and respiratory rate, bad compliance to NIMV, older age, presence of associated complication, comorbid disease, pneumonia and high baseline respiratory rate.  相似文献   
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