Experimental mouse model of optic neuritis with inflammatory demyelination produced by passive transfer of neuromyelitis optica-immunoglobulin G.

Background Although optic neuritis (ON) is a defining feature of neuromyelitis optica (NMO), appropriate animal models of NMO ON are lacking. Most NMO patients are seropositive for immunoglobulin G autoantibodies (NMO-IgG) against the astrocyte water channel aquaporin-4 (AQP4). Methods Several approaches were tested to develop a robust, passive-transfer mouse model of NMO ON, including NMO-IgG and complement delivery by: (i) retrobulbar infusion; (ii) intravitreal injection; (iii) a single intracranial injection near the optic chiasm; and (iv) 3-days continuous intracranial infusion near the optic chiasm. Results Little ON or retinal pathology was seen using approaches (i) to (iii). Using approach (iv), however, optic nerves showed characteristic NMO pathology, with loss of AQP4 and glial fibrillary acidic protein immunoreactivity, granulocyte and macrophage infiltration, deposition of activated complement, demyelination and axonal injury. Even more extensive pathology was created in mice lacking complement inhibitor protein CD59, or using a genetically modified NMO-IgG with enhanced complement effector function, including significant loss of retinal ganglion cells. In control studies, optic nerve pathology was absent in treated AQP4-deficient mice, or in wild-type mice receiving control (non-NMO) IgG and complement. Conclusion Passive transfer of NMO-IgG and complement by continuous infusion near the optic chiasm in mice is sufficient to produce ON with characteristic NMO pathology. The mouse model of NMO ON should be useful in further studies of NMO pathogenesis mechanisms and therapeutics

Hyperbaric oxygen therapy for thermal burns

Abstract Background: Hyperbaric oxygen therapy (HBOT) consists of intermittently administering 100% oxygen at pressures greater than 1 atmosphere in a pressure vessel. This technology has been used to treat a variety of disease states and has been described as helping patients who have sustained burns

Preserving the impossible: conservation of soft-sediment hominin footprint sites and strategies for three-dimensional digital data capture.

Human footprints provide some of the most publically emotive and tangible evidence of our ancestors. To the scientific community they provide evidence of stature, presence, behaviour and in the case of early hominins potential evidence with respect to the evolution of gait. While rare in the geological record the number of footprint sites has increased in recent years along with the analytical tools available for their study. Many of these sites are at risk from rapid erosion, including the Ileret footprints in northern Kenya which are second only in age to those at Laetoli (Tanzania). Unlithified, soft-sediment footprint sites such these pose a significant geoconservation challenge. In the first part of this paper conservation and preservation options are explored leading to the conclusion that to 'record and digitally rescue' provides the only viable approach. Key to such strategies is the increasing availability of three-dimensional data capture either via optical laser scanning and/or digital photogrammetry. Within the discipline there is a developing schism between those that favour one approach over the other and a requirement from geoconservationists and the scientific community for some form of objective appraisal of these alternatives is necessary. Consequently in the second part of this paper we evaluate these alternative approaches and the role they can play in a 'record and digitally rescue' conservation strategy. Using modern footprint data, digital models created via optical laser scanning are compared to those generated by state-of-the-art photogrammetry. Both methods give comparable although subtly different results. This data is evaluated alongside a review of field deployment issues to provide guidance to the community with respect to the factors which need to be considered in digital conservation of human/hominin footprints

Management of massive splenomegaly.

A case demonstrating diagnostic and therapeutic rational for surgical management of massive splenomegaly

Validation of the CogDrisk Instrument as Predictive of Dementia in Four General Community-Dwelling Populations

Background: Lack of external validation of dementia risk tools is a major limitation for generalizability and translatability of prediction scores in clinical practice and research. Objectives: We aimed to validate a new dementia prediction risk tool called CogDrisk and a version, CogDrisk-AD for predicting Alzheimer’s disease (AD) using cohort studies. Design, Setting, Participants and Measurements: Four cohort studies were identified that included majority of the dementia risk factors from the CogDrisk tool. Participants who were free of dementia at baseline were included. The predictors were component variables in the CogDrisk tool that include self-reported demographics, medical risk factors and lifestyle habits. Risk scores for Any Dementia and AD were computed and Area Under the Curve (AUC) was assessed. To examine modifiable risk factors for dementia, the CogDrisk tool was tested by excluding age and sex estimates from the model. Results: The performance of the tool varied between studies. The overall AUC and 95% CI for predicting dementia was 0.77 (0.57, 0.97) for the Swedish National study on Aging and Care in Kungsholmen, 0.76 (0.70, 0.83) for the Health and Retirement Study - Aging, Demographics and Memory Study, 0.70 (0.67,0.72) for the Cardiovascular Health Study Cognition Study, and 0.66 (0.62,0.70) for the Rush Memory and Aging Project. Conclusions: The CogDrisk and CogDrisk-AD performed well in the four studies. Overall, this tool can be used to assess individualized risk factors of dementia and AD in various population settings

Comparison of bulk milk antibody and youngstock serology screens for determining herd status for Bovine Viral Diarrhoea Virus

BACKGROUND: This paper examines the use of Bulk Milk antibody (BM Ab), Youngstock (YS) serology (Check Tests) and Bulk Milk PCR (BM PCR) for determining the presence or absence of animals persistently infected (PI) with Bovine Viral Diarrhoea Virus (BVDV) within a herd. Data is presented from 26 herds where average herd sizes were 343 and 98 animals for dairy and beef units respectively. Seventeen herds had sufficient data to analyse using Receiver Operating Characteristic (ROC) and probability curves enabling calculation of the sensitivity and specificity of BM Ab and YS Check tests for determining the presence of PI animals within herds in this dataset. RESULTS: Using BM Ab to screen a herd for the presence of PI animals, achieved a herd level sensitivity and specificity of 80.00 % (44.39–97.48 %) and 85.71 % (42.13–99.64 %) respectively (95 % confidence intervals quoted). Sensitivity and specificity of YS Check Tests at a cut off of 3/10 Ab positive YS were 81.82 % (48.22–97.72 %) and 66.67 % (22.28–95.67 %) respectively (95 % confidence interval). These results were achieved by comparing the screening tests to whole herd PI searches that took place 1–19 months after the initial screen with a mean interval of 8 months. Removal of this delay by taking BM samples on the day of a whole herd test and simulating a YS Check Test from the herd test data produced improvements in the reliability of the Check Tests. BM Ab sensitivity and specificity remained unchanged. However, the Check Test sensitivity and specificity improved to 90.9 % (58.72–99.77 %) and 100 % (54.07–100 %) respectively (95 % confidence interval) at a cut of off 2.5/10 Ab positive animals. Our limited BM PCR results identified 5/23 dairy farms with a positive BM PCR result; two contained milking PIs, two had non-milking PIs and another had no PIs identified. CONCLUSIONS: Delaying a PI search following an initial herd screen decreased the diagnostic accuracy and relevance of our results. With careful interpretation, longitudinal surveillance using a combination of the techniques discussed can successfully determine farm status and therefore allow changes in BVDV status to be detected early, thus enabling prompt action in the event of a BVDV incursion

Family physicians' information seeking behaviors: A survey comparison with other specialties

BACKGROUND: Using technology to access clinical information has become a critical skill for family physicians. The aims of this study were to assess the way family physicians use the Internet to look for clinical information and how their patterns vary from those of specialists. Further, we sought a better understanding of how family physicians used just-in-time information in clinical practice. METHODS: A fax survey was provided with 17 items. The survey instrument, adapted from two previous studies, was sent to community-based physicians. The questions measured frequency of use and importance of the Internet, palm computers, Internet CME, and email for information seeking and CME. Barriers to use were explored. Demographic data was gathered concerning gender, years since medical school graduation, practice location, practice type, and practice specialty. RESULTS: Family physicians found the Internet to be useful and important as an information source. They were more likely to search for patient oriented material than were specialists who more often searched literature, journals and corresponded with colleagues. Hand held computers were used by almost half of family physicians. CONCLUSION: Family physicians consider the Internet important to the practice of medicine, and the majority use it regularly. Their searches differ from colleagues in other specialties with a focus on direct patient care questions. Almost half of family physicians use hand held computers, most often for drug reference

Review: ‘Gimme five’: future challenges in multiple sclerosis. ECTRIMS Lecture 2009

This article is based on the ECTRIMS lecture given at the 25th ECTRIMS meeting which was held in Düsseldorf, Germany, from 9 to 12 September 2009. Five challenges have been identified: (1) safeguarding the principles of medical ethics; (2) optimizing the risk/benefit ratio; (3) bridging the gap between multiple sclerosis and experimental autoimmune encephalitis; (4) promoting neuroprotection and repair; and (5) tailoring multiple sclerosis therapy to the individual patient. Each of these challenges will be discussed and placed in the context of current research into the pathogenesis and treatment of multiple sclerosis

IL-4-secreting CD4+ T cells are crucial to the development of CD8+ T-cell responses against malaria liver stages.

CD4+ T cells are crucial to the development of CD8+ T cell responses against hepatocytes infected with malaria parasites. In the absence of CD4+ T cells, CD8+ T cells initiate a seemingly normal differentiation and proliferation during the first few days after immunization. However, this response fails to develop further and is reduced by more than 90%, compared to that observed in the presence of CD4+ T cells. We report here that interleukin-4 (IL-4) secreted by CD4+ T cells is essential to the full development of this CD8+ T cell response. This is the first demonstration that IL-4 is a mediator of CD4/CD8 cross-talk leading to the development of immunity against an infectious pathogen

Assessing risk of breast cancer in an ethnically South-East Asia population (results of a multiple ethnic groups study)

10.1186/1471-2407-12-529BMC Cancer12-BCMA