Visualization of transplanted cells within the myocardium

Intra-myocardial and intra-coronary transplantation of somatic stem cells as a therapy of heart failure is currently under clinical evaluation. A major limitation of all clinical studies dealing with myocardial cell engraftment is the inability to track the fate of the transplanted cells. This would be crucial for the scientific interpretation and monitoring of possible contribution of engrafted cells to improved cardiac function. We present an overview of all publications focusing on promising novel technologies that may allow for short- and long-term follow up of transplanted cells by visualization. Clinicians should consider appropriate bioimaging methods for in vivo visualization of engrafted cells in the heart when designing clinical studies.     

Percutaneous transluminal coronary angioplasty of a right coronary artery arising from the left main coronary artery

Angioplasty of anomalous coronary arteries presents unique technical challenges. Correct guiding catheter selection is important to ensure adequate access to the anomalous vessel and to provide support to cross the lesion. A case of successful PTCA of a lesion in an anomalous right coronary artery arising from the left main coronary artery is presented. © 1993 Wiiey-Liss, Inc.     

Proliferative action of mast-cell tryptase is mediated by PAR2, COX2, prostaglandins,and PPARgamma : Possible relevance to human fibrotic disorders

Mast-cell products can stimulate fibroblast proliferation, implying that these cells are key players in fibrosis. One mast-cell product, the serine protease tryptase, is known to activate protease-activated receptor 2 (PAR2) and cause proliferation of fibroblasts. We found that recombinant tryptase, human mast-cell (HMC-1) supernatant, which contains tryptase, and the PAR2-activating peptide SLIGKV exert fibroproliferative actions in human fibroblasts. Here we report insights into this action, which after activation of PAR2 leads to increased expression of cyclooxygenase 2 (COX2), a key enzyme in the biosynthesis of prostaglandins, and consequently to enhanced prostaglandin synthesis. Subsequent cell proliferation is mediated by the prostaglandin 15-deoxy-Delta(12,14)-prostaglandin J(2), which acts via the nuclear peroxisome proliferator-activated receptor gamma (PPARgamma). Fibroblast proliferation induced by tryptase and PAR2 agonist peptide can be blocked by antagonists of COX2 and PPARgamma, implying that the proliferative effect of tryptase is PAR2-initiated but depends on COX2, 15-deoxy-Delta(12,14)-prostaglandin J(2), and PPARgamma. This previously uncharacterized pathway could be of relevance for human fibrotic diseases. For instance, increased numbers of activated mast cells are correlated with fibrosis in testes of infertile men. In these cases all components of the signaling pathway of tryptase were detected as well as expression of COX2. Therefore, our study describes as-yet-unknown interactions between mast cells and fibroblasts, which could be relevant for human fibrotic diseases.     

Long-Term Lithium Treatment Reduces Glucose Metabolism in the Cerebellum and Hippocampus of Nondemented Older Adults: An [18F]FDG-PET Study

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Influence of magnetic field strength and image registration strategy on voxel‐based morphometry in a study of Alzheimer's disease

Multi‐centre data repositories like the Alzheimer's Disease Neuroimaging Initiative (ADNI) offer a unique research platform, but pose questions concerning comparability of results when using a range of imaging protocols and data processing algorithms. The variability is mainly due to the non‐quantitative character of the widely used structural T1‐weighted magnetic resonance (MR) images. Although the stability of the main effect of Alzheimer's disease (AD) on brain structure across platforms and field strength has been addressed in previous studies using multi‐site MR images, there are only sparse empirically‐based recommendations for processing and analysis of pooled multi‐centre structural MR data acquired at different magnetic field strengths (MFS). Aiming to minimise potential systematic bias when using ADNI data we investigate the specific contributions of spatial registration strategies and the impact of MFS on voxel‐based morphometry in AD. We perform a whole‐brain analysis within the framework of Statistical Parametric Mapping, testing for main effects of various diffeomorphic spatial registration strategies, of MFS and their interaction with disease status. Beyond the confirmation of medial temporal lobe volume loss in AD, we detect a significant impact of spatial registration strategy on estimation of AD related atrophy. Additionally, we report a significant effect of MFS on the assessment of brain anatomy (i) in the cerebellum, (ii) the precentral gyrus and (iii) the thalamus bilaterally, showing no interaction with the disease status. We provide empirical evidence in support of pooling data in multi‐centre VBM studies irrespective of disease status or MFS. Hum Brain Mapp 35:1865–1874, 2014. © 2013 Wiley Periodicals, Inc.     

Tweet Content Related to Sexually Transmitted Diseases: No Joking Matter

Background

Online social media, such as the microblogging site Twitter, have become a space for speedy exchange of information regarding sexually transmitted diseases (STDs), presenting a potential risk environment for how STDs are portrayed. Examining the types of “tweeters” (users who post messages on Twitter) and the nature of “tweet” messages is important for identifying how information related to STDs is posted in online social media.

Objective

The intent of the study was to describe the types of message emitters on Twitter in relation to two different STDs—chlamydia and human immunodeficiency virus (HIV)—as well as the nature of content tweeted, including how seriously the topic was treated.

Methods

We used the Twitter search engine to look for tweets posted worldwide from August 1-7, 2013, and from September 1-7, 2013, containing the words “chlamydia” or “HIV”, and the hashtags “#chlamydia” or “#HIV”. Tweeters were classified by two independent reviewers according to the type of avatar of the user (human, logo, or fantasy), the identification of the emitter (identifiable, semi-identifiable, or non-identifiable), and the source (private company, general media, scientific media, non-governmental, individual account, academic institution, government department, or undefined). Tweet messages were also independently classified according to their nature (serious or jokes/funny), and whether their main message was factual or of a personal nature/experience.

Results

A total of 694 tweets were posted by 426 different users during the first 7 days of August and September, containing the hashtags and/or simple words “chlamydia” and/or “HIV”. Jokes or funny tweets were more frequently posted by individual users (89%, 66/74), with a human avatar (81%, 60/74), from a non-identifiable user (72%, 53/74), and they were most frequently related to chlamydia (76%, 56/74). Serious tweets were most frequently posted by the general media (20.6%, 128/620), using a logo avatar (66.9%, 415/620), and with identifiable accounts (85.2%, 528/620). No government departments, non-governmental organizations, scientific media, or academic institutions posted a joke on STDs. A total of 104 of these analyzed tweets were re-tweeted messages, belonging to 68 unique tweets. The content was serious (99%, 67/68), factual (90%, 52/58), and about HIV (85%, 58/68).

Conclusions

Social media such as Twitter may be an important source of information regarding STDs provided that the topic is presented appropriately. Reassuringly, the study showed that almost 9/10 of tweets on STDs (chlamydia and HIV) were of serious content, and many of the tweets that were re-tweeted were facts. The jokes that were tweeted were mainly about chlamydia, and posted by non-identifiable emitters. We believe social media should be used to an even larger extent to disseminate correct information about STDs.