Human Herpesvirus 6 in Bronchalveolar Lavage Fluid after Lung Transplantation: A Risk Factor for Bronchiolitis Obliterans Syndrome?

Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.     

A study of the freeze-drying conditions of calixarene based solid lipid nanoparticles.

In this note, we report a study of cryoprotectant carbohydrate (glucose, fructose, mannose and maltose) effects on the reconstitution of calixarene based solid lipid nanoparticle (SLN) suspensions after freeze-drying, studied by atomic force microscopy and photon correlation spectroscopy. All carbohydrates tested showed excellent cryoprotection and redispersion properties with the calixarene based SLNs.     

Improved Assessment of Significant Activation in Functional Magnetic Resonance Imaging (fMRI): Use of a Cluster-Size Threshold

The typical functional magnetic resonance (fMRI) study presents a formidable problem of multiple statistical comparisons (i.e, > 10,000 in a 128 x 128 image). To protect against false positives, investigators have typically relied on decreasing the per pixel false positive probability. This approach incurs an inevitable loss of power to detect statistically significant activity. An alternative approach, which relies on the assumption that areas of true neural activity will tend to stimulate signal changes over contiguous pixels, is presented. If one knows the probability distribution of such cluster sizes as a function of per pixel false positive probability, one can use cluster-size thresholds independently to reject false positives. Both Monte Carlo simulations and fMRI studies of human subjects have been used to verify that this approach can improve statistical power by as much as fivefold over techniques that rely solely on adjusting per pixel false positive probabilities.     

Evaluation of loose bodies in the elbow with MR imaging

The evaluation of loose bodies in the elbow is usually done by means of clinical examination, radiography, and postarthrographic computed tomography (CT). The authors review their experience with magnetic resonance (MR) imaging in place of postarthrographic CT for the evaluation of loose bodies in the elbow. The prospective interpretation of MR studies of the elbow in 20 patients was compared with arthroscopic findings. All elbows were imaged in multiple planes with thin sections, surface coils, and combinations of T1, T2, and proton-density weighting. The sensitivity for showing loose bodies with MR imaging was 100%, and the specificity was 67%. Because this was a nonblinded study, the results are biased and caution must be used when extrapolating these results to the general population. In this limited experience, MR imaging has reliably shown loose bodies in the elbow, and in the authors' institutions has replaced postarthrographic CT for that purpose.     

Lhermitte-Duclos disease

Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum) is a rare pseudo-neoplastic disorder of the cerebellum with typical MRI findings. A 25-year-old man presenting with progressive neck pain, dizziness, and impaired vision is reported. CT and MRI revealed a left cerebellar haemispheric mass and obstructive hydrocephalus. Lhermitte-Duclos disease was histologically confirmed after surgical removal of the lesion. The typical MRI appearance of a nonenhancing haemispheric cerebellar mass with preservation and exaggeration of the normal gyral pattern allows pre-operative diagnosis of this condition. The literature is reviewed and clinical presentation, radiology and histopathology are discussed.