The evaluation of left ventricular systolic and diastolic functions in patients with Friedreich ataxia. A pulse tissue Doppler study

Friedreich's ataxia (FRDA), the most common subtype of early onset hereditary ataxia, is an autosomal recessive neurodegenerative disorder caused by unstable GAA expansions. Two-dimensional, pulse, and pulse tissue Doppler echocardiographic examinations were performed on 21 patients with GAA expansion. There was no association between left ventricle ejection fraction, tissue Doppler systolic s wave, and left ventricle diastolic functions examined by pulse and tissue Doppler. The septum thickness of patients with Friedreich's ataxia was significantly increased when compared with that of the control group and wall thickness was found to be associated with GAA repeats. In patients with FRDA, despite a correlation between genetic abnormality with left ventricular early and late diastolic parameters, global diastolic functions were preserved when examined by tissue Doppler.     

Intracytoplasmic cytokine levels and neutrophil functions in early clinical stage of type 1 diabetes

Studies indicate that both CD4(+) and CD8(+) T lymphocytes and their cytokines play a critical role in different clinical stages of type 1 diabetes (T1D). Disturbances of oxidative burst and phagocytic activities in neutrophils of diabetic patients compared to uncontrolled disease support the importance of neutrophil functions in the treatment and follow up of diabetic patients. This study is designed in order to investigate Th1 and Th2 cytokine profiles and neutrophil functions in early clinical stage of T1D. Patients diagnosed as T1D but not yet under insulin therapy (Group 1; n=15) and T1D patients with disease duration of <3 months (Group 2; n=20) were compared to healthy subjects (Group 3; n=15). All subjects with T1D were positive for islet cell antibody (ICA) and glutamic acid decarboxylase antibody (GADA), their fasting glucose levels were >126 mg/dl and A1(c) levels were >8. Intracytoplasmic interleukin (IL)-2, IL-10, interferon (IFN)-gamma and tumour necrosis factor (TNF)-alpha levels of isolated CD4(+) and CD8(+) T cells, and neutrophil functions were determined by flow cytometry. Intracellular TNF-alpha level of CD4(+) T lymphocytes was significantly decreased in Group 1 compared to Group 2 and healthy subjects. In contrast, TNF-alpha in CD8(+) T lymphocytes was higher in Group 1 compared to Group 2. Increased TNF-alpha content of CD8(+) T lymphocytes was also obtained in Groups 1 and 2 compared to healthy subjects. Increased TNF-alpha secretion of CD8(+) T cells might reflect the role of CD8(+) T cells in beta cell destruction. Similar to cytokine content, phagocytic and oxidative burst activities in Group 1 were significantly lower compared to Group 2 and healthy subjects. Impaired neutrophil functions could be recovered by the treatment of the disease.     

High-fat liquid “Lieber-DeCarli” diet for an animal model of nonalcoholic steatohepatitis: does it really work?

We could not reproduce the model described by Lieber et al for nonalcoholic steatohepatitis model in rats. In our trial the high fat liquid diet group of rats gained nearly 100 g or less weight compared to the mean weight gain stated in the original article. However, the fasting glucose level was statistically higher in this group as compared to the chow diet group. Some pathological abnormalities in the duodenum and jejunum samples were observed in the high fat liquid diet group. We do not know the exact reason for these changes. Overall, our study results arose some suspicions about the reproducibility of the model. Furthermore, to the best of our knowledge, no study using the proposed model has been published so far.     

Partial cardiac autotransplantation for reduction of the left atrium

Various surgical procedures have been employed to treat a greatly enlarged left atrium. We review the use of partial cardiac autotransplantation to reduce left atrial volume in 7 patients with rheumatic mitral valve disease and left atrial and ventricular volume in 2 patients with idiopathic dilated cardiomyopathy. There were 5 males and 4 females aged 25 to 62 years. The patients with rheumatic etiology had atrial fibrillation, while those with dilated cardiomyopathy had sinus rhythm. The mitral valve was replaced in 6 patients and reconstructed in 3. Mean aortic cross clamp time in the operations involving isolated left atrial resection was 119 +/- 44 min. Mean left atrial volume fell from 331 mL to 92 mL, while mean left atrial diameter decreased from 8.6 cm to 4.7 cm. Sinus rhythm was restored in 5 of the 7 patients who had preoperative atrial fibrillation. There was no operative mortality. The patients with dilated cardiomyopathy died in the postoperative period, one on the 14th day from low cardiac output and the other on the 113th day from multiorgan failure. Partial cardiac autotransplantation can be effective in reducing heart chamber size in selected patients, especially those with giant left atrium.     

The association of mean platelet volume levels with hypertensive retinopathy

The pathophysiological mechanism of hypertensive retinopathy (HR) is not fully established. Elevated blood pressure alone does not fully account for the extent of retinopathy so other pathogenic mechanisms may be involved, such as increased platelet activation. Mean platelet volume (MPV) is a marker of platelet activation. Therefore, this study was designed to answer the following questions: Do MPV levels change in HR? and is there any relation between degree of HR and MPV levels? This study included newly diagnosed and 57 untreated essential hypertensive patients with HR. The hypertensive patients were divided into two groups according to the Keith, Wagener classification. Group 1 comprised 29 hypertensive patients with grade 1 HR with a mean age of 56.8 +/- 9.7 years. Group 2 comprised 28 hypertensive patients with grade 2 HR with a mean age of 58.1 +/- 10.3 years. Twenty-seven normotensive subjects who were the healthy participants and had undergone the check-up program were used as the control group. Fundoscopic examination, metabolic parameters and MPV levels were measured in all groups. The level of MPV in group 2 was significantly higher than in group 1 (8.9 +/-0 0.8 fl vs. 8.3 +/- 0.8 fl, p = 0.02) and the normotensive control group (8.9 +/- 0.8 fl vs 7.8 +/- 0.7 fl, p < 0.001). It was also higher in group 1 than in normotensive control group (8.3 +/- 0.8 fl vs.7.8 +/- 0.7 fl, p < 0.01). In addition, MPV showed a positive correlation with the degree of HR in the hypertensive group (r = 0.41, p = 0.015). Our study suggests that platelet activation, a mechanism known to be involved in vascular lesions, may promote the development of HR.     

Pulmonary Artery Sarcoma Masquerading as Chronic Pulmonary Thromboembolism

We describe the case of a 60-year-old woman who presented with pulmonary artery sarcoma, a very rare tumor of the cardiovascular system. Her tumor was initially misdiagnosed as chronic pulmonary thromboembolism, and she underwent pulmonary endarterectomy.Early diagnosis of primary pulmonary artery sarcoma is crucial. That alternative should always be considered before settling on a diagnosis of pulmonary embolism. Suspicion should be aroused by the failure of anticoagulant treatment to alleviate pulmonary perfusion abnormalities and systemic symptoms. Surgical resection of the tumor—preferably by pulmonary endarterectomy, followed by reconstruction as needed—is currently the most promising treatment for pulmonary artery sarcoma.     

Blood oxygenation level-dependent (BOLD) MRI of human skeletal muscle at 1.5 and 3 T

Purpose:

To evaluate the dependence of skeletal muscle blood oxygenation level‐dependent (BOLD) effect and time course characteristics on magnetic field strength in healthy volunteers using an ischemia/reactive hyperemia paradigm.

Materials and Methods:

Two consecutive skeletal muscle BOLD magnetic resonance imaging (MRI) measurements in eight healthy volunteers were performed on 1.5 T and 3.0 T whole‐body MRI scanners. For both measurements a fat‐saturated multi‐shot multiecho gradient‐echo EPI sequence was applied. Temporary vascular occlusion was induced by suprasystolic cuff compression of the thigh. T2* time courses were obtained from two different calf muscles and characterized by typical curve parameters. Ischemia‐ and hyperemia‐induced changes in R2* (ΔR2*) were calculated for both muscles in each volunteer at the two field strengths.

Results:

Skeletal muscle BOLD changes are dependent on magnetic field strength as the ratio ΔR2*(3.0 T)/ΔR2*(1.5 T) was found to range between 1.6 and 2.2. Regarding time course characteristics, significantly higher relative T2* changes were found in both muscles at 3.0 T.

Conclusion:

The present study shows an approximately linear field strength dependence of ΔR2* in the skeletal muscle in response to ischemia and reactive hyperemia. Using higher magnetic fields is advisable for future BOLD imaging studies of peripheral limb pathologies. J. Magn. Reson. Imaging 2012;35:1227‐1232. © 2012 Wiley Periodicals, Inc.     

Twisting mice move the dystonia field forward

A common form of the hyperkinetic movement disorder dystonia is caused by mutations in the gene TOR1A (located within the DYT1 locus), which encodes the ATPase torsinA. The underlying neurobiological mechanisms that result in dystonia are poorly understood, and progress in the field has been hampered by the absence of a dystonia-like phenotype in animal models with genetic modification of Tor1a. In this issue of the JCI, Liang et al. establish the first animal model with a dystonic motor phenotype and link torsinA hypofunction to the development of early neuropathological changes in distinct sensorimotor regions. The findings of this study will likely play an important role in elucidating the neural substrate for dystonia and should stimulate systematic neuropathological and imaging studies in carriers of TOR1A mutations.