An ultrasound-based comparative study on carotid plaques in HIV-positive patients vs. atherosclerotic and arteritis patients: atherosclerotic or inflammatory lesions?

BACKGROUND: We have previously described two cases of HIV-1-positive patients undergoing surgery for stenosis of the internal carotid arteries. Histology revealed an extensive inflammatory infiltration of the vascular wall and no evidence of atheromasic plaque. This unexpected pattern of carotid damage prompted us to perform a more accurate investigation of the characteristics of carotid plaques in a group of HIV-positive patients. The results were compared with those obtained from young patients affected by atherosclerosis of the epi-aortic vessels and patients with arteritis. METHODS: The patients underwent ultrasonography of the epi-aortic vessels using one of the latest generation power color-Doppler with 7.5 MHz probes. RESULTS: The study population included 61 HIV-positive patients and 47 HIV-negative patients (37 atherosclerotic and 10 with arteritis). Compared with HIV-negative atherosclerotic patients, there were significantly higher proportions of HIV-positive patients with iso-hypoechogenic lesions (81.8 vs. 29%) that were homogeneous both in their parietal and endoluminal portions (96.7 vs. 21.6% and 88.5 vs. 54.0%, respectively), with a smooth or slightly irregular surface (99.0 vs. 56.7%) (P=0.001 for all differences). No statistically significant differences were seen between HIV-positive and arteritis patients. CONCLUSION: Our study evidenced that the ultrasonographic structure of the epi-aortic lesions in HIV-positive patients substantially differ from those of the plaques in atherosclerotic patients, although they share similar characteristics with patients affected by arteritis. Further investigations are warranted to better define the structure and the mechanism of onset of these lesions.     

Sequential algorithms combining non-invasive markers and biopsy for the assessment of liver fibrosis in chronic hepatitis B

AIM： To assess the performance of several noninvasive markers and of our recently proposed stepwise combination algorithms to diagnose significant fibrosis （F ≥ 2 by METAVIR） and cirrhosis （F4 by METAVIR） in chronic hepatitis B （CHB）.
METHODS： One hundred and ten consecutive patients （80 males, 30 females, mean age： 42.6 ± 11.3） with CHB undergoing diagnostic liver biopsy were included. AST-to-Platelet ratio （APRI）, Forns＇ index, AST-to-ALT Ratio, Goteborg University Cirrhosis Index （GUCD, Hui＇s model and Fibrotest were measured on the day of liver biopsy. The performance of these methods and of sequential algorithms combining Fibrotest, APRI and biopsy was defined by positive （PPV） and negative （NPV） predictive values, accuracy and area under the curve （AUC）.
RESULTS： PPV for significant fibrosis was excellent （100%） with Forns and high （〉 92%） with APR1, GUCI, Fibrotest and Hui. However, significant fibrosis could not be excluded by any marker （NPV 〈 65%）. Fibretest had the best PPV and NPV for cirrhosis （87% and 90%, respectively）. Fibrotest showed the best AUC for both significant fibrosis and cirrhosis （0.85 and 0.76, respectively）. Stepwise combination algorithms of APR1, Fibrotest and biopsy showed excellent performance （0.96 AUC, 100% NPV） for significant fibrosis and 0.95 AUC, 98% NPV for cirrhosis, with 50%-80% reduced need for liver biopsy.
CONCLUSION： In CHB sequential combination of APRI, Fibrotest and liver biopsy greatly improves the diagnostic performance of the single non-invasive markers. Need for liver biopsy is reduced by 50%-80% but cannot be completely avoided. Non-invasive markers and biopsy should be considered as agonists and not antagonists towards the common goal of estimating liver fibrosis.     

Successful stenting of bilateral multiple renal arteries in a patient with renovascular hypertension

We describe the use of stenting in multiple renal arteries with severe ostial stenoses. A 62-year-old male with long-standing arterial hypertension despite treatment with multiple antihypertensive medications and mild renal impairment, appeared to have 5 renal arteries, 4 of which had severe ostial stenoses. Successful stent implantation of these 4 lesions was performed in one session. At 3-month follow up, the patient did well with adequate blood pressure control. In conclusion, stenting of ostial stenoses in multiple renal arteries appears to be a feasible and useful option in patients with renovascular hypertension.     

Selective depletion of macrophages in atherosclerotic plaques via macrophage-specific initiation of cell death

Macrophages play a central role in atherosclerotic plaque destabilization, leading to acute coronary syndromes and sudden death. Removal of macrophages from plaques via pharmacological therapy may therefore represent a promising approach to stabilize vulnerable, rupture-prone lesions. In this review, we summarize the current therapeutic means to induce macrophage cell death in atherosclerotic plaques without affecting smooth muscle cell viability, and their potential pitfalls.     

Bortezomib-induced peripheral neurotoxicity: a neurophysiological and pathological study in the rat

Bortezomib is a new proteasome inhibitor with a high antitumor activity, but also with a potentially severe peripheral neurotoxicity. To establish a preclinical model and to characterize the changes induced on the peripheral nerves, dorsal root ganglia (DRG) and spinal cord, bortezomib was administered to Wistar rats (0.08, 0.15, 0.20, 0.30 mg/kg/day twice [2q7d] or three times [3q7d] weekly for a total of 4 weeks). At baseline, on days 14, 21 and 28 after the beginning the treatment period and during a 4-week follow-up period sensory nerve conduction velocity (SNCV) was determined in the tail of each animal. Sciatic nerve, DRG and spinal cord specimens were processed for light and electron microscope observations and morphometry. At the maximum tolerated dose bortezomib induced a significant reduction in SNCV, with a complete recovery at the end of the follow-up period. Sciatic nerve examination and morphometric determinations demonstrated mild to moderate pathological changes, involving predominantly the Schwann cells and myelin, although axonal degeneration was also observed. Bortezomib-induced changes were also observed in DRG and they were represented by satellite cell intracytoplasmatic vacuolization due to mitochondrial and endoplasmic reticulum damage, closely resembling the changes observed in sciatic nerve Schwann cells. Only rarely did the cytoplasm of DRG neurons has a dark appearance and clear vacuoles occurring in the cytoplasm. Spinal cord was morphologically normal. This model is relevant to the neuropathy induced by bortezomib in the treatment of human malignancies and it could be useful in increasing our knowledge regarding the mechanisms underlying bortezomib neurotoxicity.     

Panel review of anaplastic oligodendroglioma from European Organization For Research and Treatment of Cancer Trial 26951: assessment of consensus in diagnosis, influence of 1p/19q loss, and correlations with outcome

The diagnosis of anaplastic oligodendroglioma (AOD) or anaplastic oligoastrocytoma (AOA) is subject to interobserver variation. The aim of this study was to estimate consensus in typing and grading of these tumors using tumor material collected in a large prospective randomized phase III study and to correlate the consensus diagnosis with the 1p/19q status of the tumors and the clinical outcome. The available pathology material of the first 150 patients, randomized into the European Organization for Research and Treatment of Cancer Trial 26951, was reviewed by an independent panel of 9 neuropathologists. The presence of deletions of 1p and 19q was assessed by fluorescence in situ hybridization with locus-specific probes. The panel reached consensus on the diagnosis of AOD in 52% of the tumors that had been diagnosed as AOD by the local pathologists, whereas only 8% of the local diagnosis of AOA was confirmed with consensus. The concordance on the panel diagnosis of AOD was high (intraclass correlation = 86%). The survival curves for AOD with 1p/19q loss, AOD without these losses, and AOA without 1p/19q loss ran separately in this order. The absence of necrosis and the presence of endothelial abnormalities were correlated with better outcomes. In multivariate analysis, patients' age, 1p/19q loss, and necrosis were identified as independent prognostic factors.     

Occupational aluminum exposure: evidence in support of its neurobehavioral impact

Aluminum is a metal with known neurotoxic properties which are linked to encephalopathy and neurodegenerative diseases. The objectives of the current meta-analysis study were: (1) to summarize neurobehavioral data obtained by epidemiological studies in occupational settings and (2) to analyze confounding within these data. The meta-analysis was based on estimates of effect sizes. Overall effect sizes were obtained by application of a random effects model. The final sample consisted of nine studies examining 449 exposed and 315 control subjects. The mean urinary aluminum concentrations in the exposed groups ranged from 13 to 133 microg/l. Six neuropsychological tests, which yielded 10 performance variables, were analyzed. Nine overall effect sizes indicated an inferior performance for the exposed group. A significant overall effect size (d(RE)=-0.43) was obtained for the digit symbol test measuring speed-related components of cognitive and motor performance. Moreover, the individual effect sizes obtained for this test suggested an exposure-response relationship. Results obtained from either raw or adjusted mean scores revealed that confounding in the data could not be excluded. The results were compared to studies not included here due to a shortage of required data. Similarities were discussed in terms of sensitivity of the tests for detecting aluminum-related changes in brain function. There was concurring evidence from different studies that urinary Al concentrations below 135 microg/l have an impact on cognitive performance. The significant effect for the digit symbol might be related to its multifaceted character which requires functioning in different components of cognitive and motor performance. This feature could possibly turn the test into a screening instrument for neurobehavioral effects. However, additional studies are necessary to verify and to differentiate the effect of aluminum on cognitive performance. From a neuropsychological perspective, implicit and explicit memory, visuo-spatial and central odor processing should be examined. A measure of verbal intelligence should be included in order to address the influence of confounding. Internationally standardized exposure measures would enhance the comparability of studies.