Transduction profiles in minipig following MRI guided delivery of AAV-5 into thalamic and corona radiata areas.

BACKGROUND: As a step towards clinical use of AAV-mediated gene therapy, brains of large animals are used to settle delivery parameters as most brain connections, and relative sizes in large animals and primates, are reasonably common. Prior to application in the clinic, approaches that have shown to be successful in rodent models are tested in larger animal species, such as dogs, non-human primates, and in this case, minipigs. NEW METHOD: We evaluated alternate delivery routes to target the basal ganglia by injections into the more superficial corona radiata, and, deeper into the brain, the thalamus. Anatomically known connections can be used to predict the expression of the transgene following infusion of AAV5. For optimal control over delivery of the vector with regards to anatomical location in the brain and spread in the tissue, we have used magnetic resonance image-guided convection-enhanced diffusion delivery. RESULTS: While the transduction of the cortex was observed, only partial transduction of the basal ganglia was achieved via the corona radiata. Thalamic administration, on the other hand, resulted in widespread transduction from the midbrain to the frontal cortex COMPARISON WITH EXISTING METHODS: Compared to other methods, such as delivery directly to the striatum, thalamic injection may provide an alternative when for instance, injection into the basal ganglia directly is not feasible. CONCLUSIONS: The study results suggest that thalamic administration of AAV5 has significant potential for indications where the transduction of specific areas of the brain is required.

Transduction patterns in the CNS following various routes of AAV-5-mediated gene delivery.

Various administration routes of adeno-associated virus (AAV)-based gene therapy have been examined to target the central nervous system to answer the question what the most optimal delivery route is for treatment of the brain with certain indications. In this study, we evaluated AAV5 vector system for its capability to target the central nervous system via intrastriatal, intrathalamic or intracerebroventricular delivery routes in rats. AAV5 is an ideal candidate for gene therapy because of its relatively low level of existing neutralizing antibodies compared to other serotypes, and its broad tissue and cell tropism. Intrastriatal administration of AAV5-GFP resulted in centralized localized vector distribution and expression in the frontal part of the brain. Intrathalamic injection showed transduction and gradient expression from the rostral brain into lumbar spinal cord, while intracerebroventricular administration led to a more evenly, albeit relatively superficially distributed, transduction and expression throughout the central nervous system. To visualize the differences between localized and intra-cerebral spinal fluid administration routes, we compared intrastriatal to intracerebroventricular and intrathecal administration of AAV5-GFP. Together, our results demonstrate that for efficient transgene expression, various administration routes can be applied.

Correction to: Towards a patient journey perspective on causes of unplanned readmissions using a classification framework: results of a systematic review with narrative synthesis.

Due to an error introduced during copyediting of this article [1], following corrections need to be made.

Towards a patient journey perspective on causes of unplanned readmissions using a classification framework: results of a systematic review with narrative synthesis.

BACKGROUND: Several literature reviews have been published focusing on the prevalence and/or preventability of hospital readmissions. To our knowledge, none focused on the different causes which have been used to evaluate the preventability of readmissions. Insight into the range of causes is crucial to understand the complex nature of readmissions. We conducted a systematic review to: (1) evaluate the range of causes of unplanned readmissions in a patient journey, and (2) present a cause classification framework that can support future readmission studies. METHODS: A literature search was conducted in PUBMED and EMBASE using "readmission" and "avoidability" or "preventability" as key terms. Studies that specified causes of unplanned readmissions were included. The causes were classified into eight preliminary root causes: Technical, Organization (integrated care), Organization (hospital department level), Human (care provider), Human (informal caregiver), Patient (self-management), Patient (disease), and Other. The root causes were based on expert opinions and the root cause analysis tool of PRISMA (Prevention and Recovery Information System for Monitoring and Analysis). The range of different causes were analyzed using Microsoft Excel. RESULTS: Forty-five studies that reported 381 causes of readmissions were included. All studies reported causes related to organization of care at the hospital department level. These causes were often reported as preventable. Twenty-two studies included causes related to patient's self-management and 19 studies reported causes related to patient's disease. Studies differed in which causes were seen as preventable or unpreventable. None reported causes related to technical failures and causes due to integrated care issues were reported in 18 studies. CONCLUSIONS: This review showed that causes for readmissions were mainly evaluated from a hospital perspective. However, causes beyond the scope of the hospital can also play a major role in unplanned readmissions. Opinions regarding preventability seem to depend on contextual factors of the readmission. This study presents a cause classification framework that could help future readmission studies to gain insight into a broad range of causes for readmissions in a patient journey.

Associated conditions in small fiber neuropathy - a large cohort study and review of the literature.

BACKGROUND AND PURPOSE: Small fiber neuropathy (SFN) is a common disorder leading to neuropathic pain and autonomic symptoms. The objective of this study was to investigate associated conditions in a large cohort of SFN patients and compare the prevalence to healthy individuals. METHODS: A total of 921 patients with pure SFN were screened according to a standardized comprehensive diagnostic algorithm and compared with literature findings. RESULTS: No associated condition could be found in 53% of the patients. Autoimmune diseases, sodium channel gene mutations, diabetes mellitus including glucose intolerance, and vitamin B12 deficiencies were more prevalent than reported literature findings, followed by alcohol abuse, chemotherapy, monoclonal gammopathy of undetermined significance, and haemochromatosis. In patients who were already known with a possible underlying condition at screening, additional underlying conditions were still found in another 26.7% of patients. CONCLUSIONS: Based on these results, it is recommended that patients with pure SFN are screened at least for autoimmune diseases, sodium channel gene mutations, diabetes mellitus including glucose intolerance, and vitamin B12 deficiency, even when they already have a potential underlying condition at referral.

Improving care for older patients in the acute setting: a qualitative study with healthcare providers.

BACKGROUND: The proportion of older people needing acute care is rapidly growing, thereby posing an increased burden on the acute care chain. The aim of this study is to gain more insight into the obstacles and potential improvement opportunities of the acute care process for older patients arriving at the hospital. METHODS: Semi-structured interviews were conducted to determine the experiences of 18 different primary (i.e. general practitioner, community nurse) and secondary healthcare professionals (i.e. emergency department (ED) nurse, ED physician, geriatric physician, geriatric nurse, ambulance nurse, acute medical unit nurse), and three experts (2 researchers, 1 older adult advisor). RESULTS: Four core themes emerged from the interviews: 1) The concept of frailty, awareness concerning frail older patients, and identification of frailty, 2) Barriers in the care process of older patients within the acute care chain, 3) Optimising the discharge process of older patients, and 4) Improvement opportunities suggested by the respondents. Early identification of frailty, improving the continuity of care by means of structured information exchange between care providers in the acute care chain, and a more generalist approach were considered important by the respondents in order to deliver appropriate care to older patients. CONCLUSION: This explorative study identified several barriers and improvement opportunities which are important to improve the quality, efficacy and appropriateness of the acute care of older patients. More seems needed in the future in order to share experiences, expertise and develop potential improvement strategies for the acute care of older patients.

AAV5-miHTT gene therapy demonstrates suppression of mutant huntingtin aggregation and neuronal dysfunction in a rat model of Huntington's disease.

Huntington's disease (HD) is a fatal progressive neurodegenerative disorder caused by a mutation in the huntingtin (HTT) gene. To date, there is no treatment to halt or reverse the course of HD. Lowering of either total or only the mutant HTT expression is expected to have therapeutic benefit. This can be achieved by engineered micro (mi)RNAs targeting HTT transcripts and delivered by an adeno-associated viral (AAV) vector. We have previously showed a miHTT construct to induce total HTT knock-down in Hu128/21 HD mice, while miSNP50T and miSNP67T constructs induced allele-selective HTT knock-down in vitro. In the current preclinical study, the mechanistic efficacy and gene specificity of these selected constructs delivered by an AAV serotype 5 (AAV5) vector was addressed using an acute HD rat model. Our data demonstrated suppression of mutant HTT messenger RNA, which almost completely prevented mutant HTT aggregate formation, and ultimately resulted in suppression of DARPP-32-associated neuronal dysfunction. The AAV5-miHTT construct was found to be the most efficient, although AAV5-miSNP50T demonstrated the anticipated mutant HTT allele selectivity and no passenger strand expression. Ultimately, AAV5-delivered-miRNA-mediated HTT lowering did not cause activation of microglia or astrocytes suggesting no immune response to the AAV5 vector or therapeutic precursor sequences. These preclinical results suggest that using gene therapy to knock-down HTT may provide important therapeutic benefit for HD patients and raised no safety concerns, which supports our ongoing efforts for the development of an RNA interference-based gene therapy product for HD.

[Lessons learned from the evacuation of the VU University Medical Centre after flooding]. / Lessen uit de evacuatie van het VUmc na wateroverlast.

On 8 September 2015, flooding of the lower floors of the VU University Medical Center in Amsterdam caused serious damage to many vital technical services, such as water and power supplies. The decision was made to completely evacuate the university hospital. This paper describes the chronology and events of that day and shares a number of important lessons that were learned, in order to help readers to optimise crisis organisation in their own institutions. A serious situation or disaster can never be standardised in protocols or manuals; flexibility, improvisation and confidence in one another's expertise and commitment are therefore essential.

Benchmarking the use of blood products in cardiac surgery to stimulate awareness of transfusion behaviour : Results from a four-year longitudinal study.

INTRODUCTION: Cardiac operations account for a large proportion of the blood transfusions given each year, leading to high costs and an increased risk to patient safety. Therefore, it is important to explore initiatives to reduce transfusion rates. This study aims to provide a benchmark for transfusion practice by inter-hospital comparison of transfusion rates, blood product use and costs related to patients undergoing coronary artery bypass grafting (CABG), valve surgery or combined CABG and valve surgery. METHODS: Between 2010 and 2013, patients from four Dutch hospitals undergoing CABG, valve surgery or combined CABG and valve surgery (n = 11,150) were included by means of a retrospective longitudinal study design. RESULTS: In CABG surgery the transfusion rate ranged between 43 and 54%, in valve surgery between 54 and 67%, and in combined CABG and valve surgery between 80 and 88%. With the exception of one hospital, the trend in transfusion rate showed a significant decrease over time for all procedures. Hospitals differed significantly in the units of blood products given to each patient, and in the use of specific transfused combinations of blood products, such as red blood cells (RBCs) and a combination of RBCs, fresh frozen plasma (FFP) and platelets. CONCLUSION: This study indicates that benchmarking blood product usage stimulates awareness of transfusion behaviour, which may lead to better patient safety and lower costs. Further studies are warranted to improve awareness of transfusion behaviour and increase the standardisation of transfusion practice in cardiac surgery.

Effective oligonucleotide-mediated gene disruption in ES cells lacking the mismatch repair protein MSH3.

We have previously demonstrated that site-specific insertion, deletion or substitution of one or two nucleotides in mouse embryonic stem cells (ES cells) by single-stranded deoxyribo-oligonucleotides is several hundred-fold suppressed by DNA mismatch repair (MMR) activity. Here, we have investigated whether compound mismatches and larger insertions escape detection by the MMR machinery and can be effectively introduced in MMR-proficient cells. We identified several compound mismatches that escaped detection by the MMR machinery to some extent, but could not define general rules predicting the efficacy of complex base-pair substitutions. In contrast, we found that four-nucleotide insertions were largely subject to suppression by the MSH2/MSH3 branch of MMR and could be effectively introduced in Msh3-deficient cells. As these cells have no overt mutator phenotype and Msh3-deficient mice do not develop cancer, Msh3-deficient ES cells can be used for oligonucleotide-mediated gene disruption. As an example, we present disruption of the Fanconi anemia gene Fancf.