Impact of IVIg on the interaction between activated T cells and microglia

When human microglia are co-cultured with activated human T lymphocytes, several cytokines become up-regulated in significant quantities. This condition can also occur at sites of inflammation in autoimmune inflammatory diseases of the central nervous system (CNS), including multiple sclerosis (MS), where T cells infiltrate the brain tissue and come in proximity to microglia. Therefore, T cell-microglia interaction is a potential avenue of drug therapy to decrease neuroinflammation. An immunomodulator used in autoimmune disorders is intravenous immunoglobulins (IVIg). The mechanisms of IVIg activity in diseases such as MS remain unclear. Here, we report that the application of IVIg to activated T cells leads to their decreased ability to engage microglia. As a result of IVIg treatment of T cells, there were reduced levels of tumor necrosis factor-alpha a and interleukin-10 in T cell-microglia co-culture. Our results add to the understanding of how IVIg may affect inflammation of the CNS.     

Surgical outcome of patients considered to have “inoperable” tumors by specialized pediatric neuro-oncological multidisciplinary teams

Purpose  

Despite the lack of evidence in literature, it is widely felt that patient outcomes will be improved by adopting a multidisciplinary team (MDT) approach to children with brain tumors. This study focuses on a series of pediatric patients treated surgically despite a MDT recommendation against surgery.     

Prevalence of restless legs syndrome in blood donors

Iron deficiency anemia has been linked to restless legs syndrome (RLS) and regular blood donation may lead to iron deficiency. It has been reported that blood donations may be associated with RLS. A recent study from Sweden found that 25% of the women donors were affected by RLS. However, this type of study has not been replicated in the United States. We conducted a study in our blood donation unit between September and October 2008. To identify those with RLS, we used the RLS diagnostic index questionnaire by Benes et al. The proportion of blood donors with RLS was estimated and the number of blood donations and hemoglobin levels were compared according to RLS status. One hundred and fifty one patients were interviewed; 7 patients who donated only platelets were excluded, leaving 144 patients for analysis. There were 13 (9.0%, 95% confidence interval [CI]: 4.9–14.9%) patients with RLS. Of these, 7 (4.9%, 95% CI: 2.0–9.8%) had possible RLS and 6 (4.2%, 95% CI: 1.5–8.9%) had major or clinically relevant RLS. There was no dramatic association between RLS and number of blood donations or hemoglobin level (all P ≥ 0.21). In our sample of blood donors in the United States, the prevalence of major RLS was 4%. We could not demonstrate an association between RLS and the frequency of blood donation or hemoglobin level in our relatively small sample; a larger sample is needed to better identify any associations. © 2010 Movement Disorder Society     

Prediction of leakage flow in a shrouded centrifugal blood pump

This article proposes a phenomenological model to predict the leakage flow in the clearance gap of shrouded centrifugal blood pumps. A good washout in the gap clearance between the rotating impeller surfaces and volute casing is essential to avoid thrombosis. However, excessive leakage flow will result in higher fluid shear stress that may lead to hemolysis. Computational fluid dynamics (CFD) analysis was performed to investigate the leakage flow in a miniaturized shrouded centrifugal blood pump operating at a speed of 2000 rpm. Based on an analytical model derived earlier, a phenomenological model is proposed to predict the leakage flow. The leakage flow rate is found to be proportional to h(α) , where h is the gap size and the exponent α ranges from 2.955 to 3.15 for corresponding gap sizes of 0.2-0.5 mm. In addition, it is observed that α is a linear function of the gap size h. The exponent α compensates for the variation of pressure difference along the circumferential direction as well as inertia effects that are dominant for larger gap clearances. The proposed model displays good agreement with computational results. The CFD analysis also showed that for larger gap sizes, the total leakage flow rate is of the same order of magnitude as the operating flow rate, thus suggesting low volumetric efficiency.     

Tissue microarrays characterise the clinical significance of a VEGF-A protein expression signature in gastrointestinal stromal tumours

A tissue microarray analysis of 22 proteins in gastrointestinal stromal tumours (GIST), followed by an unsupervised, hierarchical monothetic cluster statistical analysis of the results, allowed us to detect a vascular endothelial growth factor (VEGF) protein overexpression signature discriminator of prognosis in GIST, and discover novel VEGF-A DNA variants that may have functional significance.     

Access to spine care: a tale of two cities

INTRODUCTION: As governments struggle with increasing demand for accountability within the Canadian Health Care System and set wait-time standards, it is important to objectify data to allow a true understanding of present limitations and to facilitate comparisons to other systems. The purpose of this study was to compare wait list times for a cohort of patients requiring spinal surgery in Calgary, Alberta to a similar cohort in Sydney, Australia. METHODS: From January 1 until June 30, 2006 all outpatients admitted for spinal surgery to the Foothills Hospital were identified by the surgeons' office. Two time periods were quantified from their charts: (1) time from referral to surgical consultation; and (2) time from surgical consultation to operative intervention. From July 1 until December 31,2006 patients were similarly identified through Neurosurgical offices at the Prince of Wales Public and Private Hospitals in Sydney, Australia. RESULTS: Four hundred ninety-one surgical patients were captured during the six month period in Calgary and 155 patients during the subsequent six months in Sydney. The majority of patients in Sydney were treated in the Private Health Care system. Public patients in Sydney have access to a surgical consultant twice as fast as public patients in Calgary while private patients have access ten times faster. Access to operating room time within the public system is a rate limiting step in both countries. However, Sydney private patients receive their surgery four times faster than Calgary patients. CONCLUSIONS: Compared to Calgary, access to specialized spine care in Sydney appears more efficient not only in the Private but also the Public Health Care System. Part of this efficiency may arise from offloading from the public into the private system. Solutions proposed to reduce wait list times should consider benefits of a Private Health Care System.