Positron emission tomography (PET): evaluation of chronic periaortitis

OBJECTIVE: To evaluate the presence and extent of large-vessel inflammation in patients with chronic periaortitis (CP) using (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET). METHODS: A consecutive case series consisting of 7 patients with CP seen over a 3-year period and a control group of 14 patients with malignancy were evaluated with FDG-PET. For every case we selected 2 age- and sex-matched controls who underwent PET imaging for malignancy. The diagnosis of CP was made by means of computed tomography. PET imaging was performed at diagnosis before therapy was started. Measurement of vascular uptake was graded using a 4-point semiquantitative scale. RESULTS: All patients had evidence of grade 2+ or 3+ vascular uptake in the abdominal aorta and/or iliac artery. No controls showed vascular uptake greater than 1+. Vascular uptake in the thoracic aorta and/or in its branches was seen in 3 (43%) of 7 patients. Vascular uptake in abdominal aorta and/or iliac artery was observed in patients with CP but not in controls (100% versus 0%). There was also a significantly more frequent FDG uptake in the large thoracic arteries in case-patients compared with controls (43% versus 0%; P = 0.03). CONCLUSION: FDG-PET scan shows in patients with CP the presence of a large-vessel vasculitis involving abdominal aorta and common iliac arteries, which in some patients is also extended to thoracic aorta and/or its branches.     

Anesthesia and the developing brain: a way forward for clinical research

It is now well established that many general anesthetics have a variety of effects on the developing brain in animal models. In contrast, human cohort studies show mixed evidence for any association between neurobehavioural outcome and anesthesia exposure in early childhood. In spite of large volumes of research, it remains very unclear if the animal studies have any clinical relevance; or indeed how, or if, clinical practice needs to be altered. Answering these questions is of great importance given the huge numbers of young children exposed to general anesthetics. A recent meeting in Genoa brought together researchers and clinicians to map a path forward for future clinical studies. This paper describes these discussions and conclusions. It was agreed that there is a need for large, detailed, prospective, observational studies, and for carefully designed trials. It may be impossible to design or conduct a single study to completely exclude the possibility that anesthetics can, under certain circumstances, produce long‐term neurobehavioural changes in humans; however , observational studies will improve our understanding of which children are at greatest risk, and may also suggest potential underlying etiologies, and clinical trials will provide the strongest evidence to test the effectiveness of different strategies or anesthetic regimens with respect to better neurobehavioral outcome.     

Early Detection of Anthracycline-Induced Cardiotoxicity in Long-Term Survivors of Acute Lymphoblastic Leukemia Treated with Low Cumulative Dose

We investigated the left ventricular (LV) function, using for the first time strain (S) and strain rate (SR) imaging, in long-term survivors affected by acute lymphoblastic leukemia treated with a low cumulative dose of anthracyclines, and in presence of a normal global LV systolic and diastolic function. A total of 21 were enrolled in the study. The mean cumulative dose of anthracylines was 180 mg/m² (range: 120-210 mg/m²). As control group 21 age-sex matched healthy subjects were included. Radial S (17 ± 3% vs. 55 ± 6%, P < 0.0001) and SR (2.1 ± 0.3 vs. 3.0 ± 0.8 1\s, P < 0.0001), assessed on the midsegment of the posterior wall from the parasternal views were significantly reduced when compared with controls. Conversely, myocardial performance index was not able to discriminate between patients and controls. In this preliminary study, the myocardial deformation indices appear to be a more sensitive noninvasive technique for detecting subclinical LV dysfunction than other echocardiographic measurements.     

Effect of cardiac resynchronization therapy on cardiotrophin-1 circulating levels in patients with heart failure

Cardiotrophin-1 (CT-1) is a member of the interleukin (IL-6) family of cytokines. Plasma CT-1 levels correlate with the left ventricle mass index in patients with dilatated cardiomyopathy and congestive heart failure (CHF). The aim of this paper was to evaluate CT-1 plasma levels, before and after cardiac resynchronization therapy CRT, and to characterizeits prognostic role in patients with CHF. Fifty-two consecutive patients (M/F = 39/13; 56 ± 11 years old) underwent clinical and echocardiographic evaluation, and blood sample collection at baseline. The same evaluation was repeated 6.4 ± 0.79 months after CRT. Patients with a decreased LV end-systolic volume by at least 15% (reverse remodeling) were considered echo responders to CRT. Twenty-nine patients (56%) were responders to CRT. After CRT, only 15 patients (29%) showed increased CT-1 after CRT. They were all non responders to CRT. A multivariate, logistic modelshowed CT-1 as an independent predictor of CRT echo response (p = 0.005; OR 0.97). During follow-up (18 ± 7 months), 21 cardiac events in 18 patients occurred. A Cox multivariable model showed plasma BNP pre-CRT (p = 0.02; CI 1.2–5.6; OR 3.1) and CT1 post-CRT (p = 0.01; CI 1.4–4.3; OR 2.7) as independent predictors of cardiac events. Analysis of CT-1 plasma levels deserves future consideration for larger, longitudinal studies in patients with CHF.     

Monocyte to HDL ratio: a novel marker of resistant hypertension in CKD patients

International Urology and Nephrology - Inflammation, oxidative stress (OS), atherosclerosis and resistant hypertension (RH) are common features of chronic kidney disease (CKD) leading to a higher...     

Synthesis and Characterization of a Nearly Single Bulk Ti2AlN MAX Phase Obtained from Ti/AlN Powder Mixture through Spark Plasma Sintering

MAX phases are an advanced class of ceramics based on ternary carbides or nitrides that combine some of the ceramic and metallic properties, which make them potential candidate materials for many engineering applications under severe conditions. The present work reports the successful synthesis of nearly single bulk Ti₂AlN MAX phase (>98% purity) through solid-state reaction and from a Ti and AlN powder mixture in a molar ratio of 2:1 as starting materials. The mixture of Ti and AlN powders was subjected to reactive spark plasma sintering (SPS) under 30 MPa at 1200 °C and 1300 °C for 10 min in a vacuum atmosphere. It was found that the massive formation of Al₂O₃ particles at the grain boundaries during sintering inhibits the development of the Ti₂AlN MAX phase in the outer zone of the samples. The effect of sintering temperature on the microstructure and mechanical properties of the Ti₂AlN MAX phase was investigated and discussed.     

Hyperhomocysteinemia exacerbates the development of intimal hyperplasia in Sprague-Dawley rats: Alleviation by rosiglitazone

The amino acid intermediate homocysteine (Hcy) is formed during the metabolism of methionine to cysteine. Hyperhomocysteinemia (HHcy) is recognized as an independent risk factor for coronary atherosclerosis. The circulating levels of total Hcy (tHcy) can increase due to intake of foods rich in methionine or deficiencies of vitamins such as folate, pyridoxine and cyanocobalamin, which are required for the metabolism of Hcy. In addition, mutations in the genes coding for Hcy metabolizing enzymes can contribute to an increase in tHcy levels. Clinical and epidemiological studies have shown that an elevated level of tHcy measured in serum or plasma is a strong predictor of cardiovascular disease risk, which appears to be greatest in patients who have HHcy following a methionine load. Intimal hyperplasia (IH) (intima/media [I/M] ratio) is the universal response of a vessel to injury and may result in vasoconstriction when left unattended. The effect of dietary HHcy on balloon catheter-injured carotid artery and its modulation (if any) by the peroxisome proliferator-activated receptor agonist gamma rosiglitazone was evaluated in 12-week-old female Sprague-Dawley rats fed either a control diet or a diet containing 1% L-methionine. Once the rats were established on the diet, the group that was fed 1% L-methionine was further subdivided and either given an aqueous preparation of 3 mg/kg/day rosiglitazone or the vehicle via oral gavage for one week. This was followed by surgically injuring the left carotid artery using a Maverick Over-The-Wire catheter (2.0 mm × 20 mm, 3.2F; Boston Scientific, USA). The rats were continued on their respective diets and drug regimen for 21 days postsurgery. On day 22 of the procedure, the rats were sacrificed for collection of blood, the carotid arteries and liver for biochemical and histological evaluation. Compared with controls there was a significant increase in both tHcy levels and I/M ratio in the rats fed 1% L-methionine (5.4±0.28 μM versus 32.8±3.01 μM, P<0.002; and 0.175±0.05 versus 1.05±0.23, P<0.005, respectively). The effect of rosiglitazone in rats fed the control diet was not prominent. On the other hand, administration of rosiglitazone to the rats on the 1% L-methionine diet significantly reduced the levels of serum tHcy (16.6±2.1 μM versus 32.8±3.01 μM, P<0.001); however, the tHcy levels remained significantly elevated compared with animals on the control diet (P<0.002). The group receiving the L-methionine diet plus rosiglitazone had an inhibition in the development of IH compared with those receiving the L-methionine diet alone (I/M of 0.278±0.041 versus 1.05±0.23, P<0.01). Moreover, the development of IH in the group receiving the L-methionine diet plus rosiglitazone treatment was not significantly different from that observed in the group on the control diet without rosiglitazone (0.278±0.041 versus 0.175±0.05, respectively). These findings may have important implications in deciphering the molecular mechanisms involved in the augmentation of IH in HHcy and modulation of this process by rosiglitazone.