A mutation affecting the sodium/proton exchanger, SLC9A6, causes mental retardation with tau deposition

We have studied a family with severe mental retardation characterized by the virtual absence of speech, autism spectrum disorder, epilepsy, late-onset ataxia, weakness and dystonia. Post-mortem examination of two males revealed widespread neuronal loss, with the most striking finding being neuronal and glial tau deposition in a pattern reminiscent of corticobasal degeneration. Electron microscopic examination of isolated tau filaments demonstrated paired helical filaments and ribbon-like structures. Biochemical studies of tau demonstrated a preponderance of 4R tau isoforms. The phenotype was linked to Xq26.3, and further analysis identified an in-frame 9 base pair deletion in the solute carrier family 9, isoform A6 (SLC9A6 gene), which encodes sodium/hydrogen exchanger-6 localized to endosomal vesicles. Sodium/hydrogen exchanger-6 is thought to participate in the targeting of intracellular vesicles and may be involved in recycling synaptic vesicles. The striking tau deposition in our subjects reveals a probable interaction between sodium/proton exchangers and cytoskeletal elements involved in vesicular transport, and raises the possibility that abnormalities of vesicular targeting may play an important role in more common disorders such as Alzheimer's disease and autism spectrum disorder

Medical Relief Trips...What’s Missing? Exploring Ethical Issues and the Physician-Patient Relationship

"The welcome ceremony alone will leave you breathless as you become inspired by their overwhelming joy at you arrival. Here you will participate with the community and provide much needed medical care. The team will also provide care for the Talibe boys in Theis who go without medical care and are left to face disease on their own (Senegal, 2009).

Approach for Predicting Production Scenarios Focused on Cross Impact Analysis

AbstractOne of the most consistent challenges in business is anticipating what the future holds and what impact it may have on current production systems. The scenario technique is a well-established method for developing and forecasting multiple future development paths for companies. However, this method is mostly employed to develop and to support strategic long-term decisions. The core idea of the approach introduced in this paper is to convey the future impact of today's decisions on production systems to employees involved in production planning processes. With the help of immersive visualization, performed in virtual reality (VR) systems, planning participants can perceive how the factory must adapt to fit future demands.In this paper, the focus is on the fourth phase of the scenario technique – so called scenario development – and, in particular, the cross impact analysis. With this methodology, the interrelations, or cross impacts of the different basic elements are determined. The cross impact analysis results serve as a basis for the development of a standardized tool that can be used to create probable production scenarios out of given production systems. This standardized tool will facilitate the usage of the scenario technique for factory planning projects, as it focuses the immense diversity of future uncertainties companies are faced with on the factory level

Locally Enhanced Angiogenesis Promotes Transplanted Cell Survival

A developing therapy for complete or partial loss of function in various tissues and organs involves transplanting an appropriate cell population, capable of compensating for the existing deficiencies. Clinical application of this type of strategy is currently limited by the death or dedifferentiation of the transplanted cells after delivery to the recipient. A delay in thorough vascularization of the implant area creates an environment low in oxygen and other nutrients, and likely contributes to the initial death of transplanted cells. We have addressed this problem by sustained delivery of vascular endothelial growth factor (VEGF), an initiator of angiogenesis, from a porous polymer matrix utilized simultaneously for cell delivery. As expected from previous studies, VEGF delivered from these constructs elicited an enhanced angiogenic response over a 2-week period when implanted subcutaneously in SCID mice. Hepatocytes implanted using VEGF-containing matrices demonstrated significantly greater survival after 1 week in vivo as compared with cells implanted on matrices without growth factor. The results of this study therefore indicate that enhancing vascularization in the location of transplanted cells promotes their survival. In addition, this delivery system may be used in future studies to directly promote cell survival and function by also providing growth factors specific to the transplanted cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63136/1/107632704322791709.pd

Continuum of sexual and gender-based violence risks among Syrian refugee women and girls in Lebanon

Background: A myriad of factors including socio-economic hardships impact refugees, with females being additionally exposed to various forms of sexual and gender-based violence (SGBV). The aim of this qualitative analysis was to understand and to provide new insight into the experiences of SGBV among Syrian refugee women and girls in Lebanon. Methods: The data are gained from a larger mixed-methods study, investigating the experiences of Syrian refugee girls in Lebanon, using an iPad and the data collection tool, SenseMaker®. The SenseMaker survey intentionally did not ask direct questions about experiences of SGBV but instead enabled stories about SGBV to become apparent from a wide range of experiences in the daily lives of Syrian girls. For this analysis, all first-person stories by female respondents about experiences of SGBV were included in a thematic analysis as well as a random selection of male respondents who provided stories about the experiences of Syrian girls in Lebanon. Results: In total, 70 of the 327 first person stories from female respondents and 42 of the 159 stories shared by male respondents included dialogue on SGBV. While experiences of sexual harassment were mainly reported by women and girls, male respondents were much more likely to talk explicitly about sexual exploitation. Due to different forms of SGBV risks in public, unmarried girls were at high risk of child marriage, whereas married girls more often experienced some form of IPV and/or DV. In abusive relationships, some girls and women continued to face violence as they sought divorces and attempted to flee unhealthy situations. Conclusions: This study contributes to existing literature by examining SGBV risks and experiences for refugees integrated into their host community, and also by incorporating the perceptions of men. Our findings shed light on the importance of recognizing the impact of SGBV on the family as a whole, in addition to each of the individual members and supports considering the cycle of SGBV not only across the woman’s lifespan but also across generations. Gendered differences in how SGBV was discussed may have implications for the design of future research focused on SGBV

Authorship representation in global emergency medicine: a bibliometric analysis from 2016 to 2020

Introduction: High-income country (HIC) authors are disproportionately represented in authorship bylines compared with those affiliated with low and middle-income countries (LMICs) in global health research. An assessment of authorship representation in the global emergency medicine (GEM) literature is lacking but may inform equitable academic collaborations in this relatively new field. Methods: We conducted a bibliometric analysis of original research articles reporting studies conducted in LMICs from the annual GEM Literature Review from 2016 to 2020. Data extracted included study topic, journal, study country(s) and region, country income classification, author order, country(s) of authors\u27 affiliations and funding sources. We compared the proportion of authors affiliated with each income bracket using Χ2 analysis. We conducted logistic regression to identify factors associated with first or last authorship affiliated with the study country. Results: There were 14 113 authors in 1751 articles. Nearly half (45.5%) of the articles reported work conducted in lower middle-income countries (MICs), 23.6% in upper MICs, 22.5% in low-income countries (LICs). Authors affiliated with HICs were most represented (40.7%); 26.4% were affiliated with lower MICs, 17.4% with upper MICs, 10.3% with LICs and 5.1% with mixed affiliations. Among single-country studies, those without any local authors (8.7%) were most common among those conducted in LICs (14.4%). Only 31.0% of first authors and 21.3% of last authors were affiliated with LIC study countries. Studies in upper MICs (adjusted OR (aOR) 3.6, 95% CI 2.46 to 5.26) and those funded by the study country (aOR 2.94, 95% CI 2.05 to 4.20) had greater odds of having a local first author. Conclusions: There were significant disparities in authorship representation. Authors affiliated with HICs more commonly occupied the most prominent authorship positions. Recognising and addressing power imbalances in international, collaborative emergency medicine (EM) research is warranted. Innovative methods are needed to increase funding opportunities and other support for EM researchers in LMICs, particularly in LICs

Neural stem cells restore myelin in a demyelinating model of Pelizaeus-Merzbacher disease

Pelizaeus-Merzbacher disease is a fatal X-linked leukodystrophy caused by mutations in the PLP1 gene, which is expressed in the CNS by oligodendrocytes. Disease onset, symptoms and mortality span a broad spectrum depending on the nature of the mutation and thus the degree of CNS hypomyelination. In the absence of an effective treatment, direct cell transplantation into the CNS to restore myelin has been tested in animal models of severe forms of the disease with failure of developmental myelination, and more recently, in severely affected patients with early disease onset due to point mutations in the PLP1 gene, and absence of myelin by MRI. In patients with a PLP1 duplication mutation, the most common cause of Pelizaeus-Merzbacher disease, the pathology is poorly defined because of a paucity of autopsy material. To address this, we examined two elderly patients with duplication of PLP1 in whom the overall syndrome, including end-stage pathology, indicated a complex disease involving dysmyelination, demyelination and axonal degeneration. Using the corresponding Plp1 transgenic mouse model, we then tested the capacity of transplanted neural stem cells to restore myelin in the context of PLP overexpression. Although developmental myelination and axonal coverage by endogenous oligodendrocytes was extensive, as assessed using electron microscopy (n = 3 at each of four end points) and immunostaining (n = 3 at each of four end points), wild-type neural precursors, transplanted into the brains of the newborn mutants, were able to effectively compete and replace the defective myelin (n = 2 at each of four end points). These data demonstrate the potential of neural stem cell therapies to restore normal myelination and protect axons in patients with PLP1 gene duplication mutation and further, provide proof of principle for the benefits of stem cell transplantation for other fatal leukodystrophies with ‘normal’ developmental myelination

Oligodendroglial modulation of fast axonal transport in a mouse model of hereditary spastic paraplegia

Oligodendrocytes are critical for the development of the plasma membrane and cytoskeleton of the axon. In this paper, we show that fast axonal transport is also dependent on the oligodendrocyte. Using a mouse model of hereditary spastic paraplegia type 2 due to a null mutation of the myelin Plp gene, we find a progressive impairment in fast retrograde and anterograde transport. Increased levels of retrograde motor protein subunits are associated with accumulation of membranous organelles distal to nodal complexes. Using cell transplantation, we show categorically that the axonal phenotype is related to the presence of the overlying Plp null myelin. Our data demonstrate a novel role for oligodendrocytes in the local regulation of axonal function and have implications for the axonal loss associated with secondary progressive multiple sclerosis