Separation of adeno-associated virus type 2 empty particles from genome containing vectors by anion-exchange column chromatography

Adeno-associated virus (AAV) empty capsids typically co-purify with genome containing AAV2 vectors purified by column chromatography. This study describes a method to remove empty capsids from genome containing vector particles by anion exchange chromatography. The separation is based on the slightly less anionic character of empty particles compared to vectors. Detailed methods to achieve AAV2 vector purification and particle separation using cation exchange resin POROS 50HS followed by anion exchange resin Q-Sepharose^xl are described. Chromatographic separation of AAV2 particles was achieved using gradients based on sodium acetate and ammonium acetate, and was optimal at pH 8.5. Efficient removal of particle surface nucleic acid impurities was found to be important to achieve good particle separation. In a large scale experiment performed using partially purified vector containing a mixture of 1.56 × 10¹⁴ vg and 2.52 × 10¹⁵ empty capsids as a starting material, the optimized anion exchange chromatography method resulted in a vector peak of 1.15 × 10¹⁴ vg containing 0.25 × 10¹⁴ empty capsids, corresponding to 74% vector yield and 86-fold reduction in empty capsids in the vector product.     

The combination of cardiorespiratory fitness and muscle strength,and mortality risk

Little is known about the combined associations of cardiorespiratory fitness (CRF) and hand grip strength (GS) with mortality in general adult populations. The purpose of this study was to compare the relative risk of mortality for CRF, GS, and their combination. In UK Biobank, a prospective cohort of >?0.5 million adults aged 40–69 years, CRF was measured through submaximal bike tests; GS was measured using a hand-dynamometer. This analysis is based on data from 70,913 men and women (832 all-cause, 177 cardiovascular and 503 cancer deaths over 5.7-year follow-up) who provided valid CRF and GS data, and with no history of heart attack/stroke/cancer at baseline. Compared with the lowest CRF category, the hazard ratio (HR) for all-cause mortality was 0.76 [95% confidence interval (CI) 0.64–0.89] and 0.65 (95% CI 0.55–0.78) for the middle and highest CRF categories, respectively, after adjustment for confounders and GS. The highest GS category had an HR of 0.79 (95% CI 0.66–0.95) for all-cause mortality compared with the lowest, after adjustment for confounders and CRF. Similar results were found for cardiovascular and cancer mortality. The HRs for the combination of highest CRF and GS were 0.53 (95% CI 0.39–0.72) for all-cause mortality and 0.31 (95% CI 0.14–0.67) for cardiovascular mortality, compared with the reference category of lowest CRF and GS: no significant association for cancer mortality (HR 0.70; 95% CI 0.48–1.02). CRF and GS are both independent predictors of mortality. Improving both CRF and muscle strength, as opposed to either of the two alone, may be the most effective behavioral strategy to reduce all-cause and cardiovascular mortality risk.     

Estimation of the duration of ventricular fibrillation using ECG single feature analysis

The duration of untreated ventricular fibrillation (VF) is of paramount importance for CPR success. Moreover, therapeutic interventions taking into account the interval between cardiac arrest onset and initiation of CPR improve outcome. This study was performed to investigate whether VF feature analysis could be used to estimate the duration of VF in patients with out-of-hospital cardiac arrest. Demographic data recorded according to the Utstein guidelines and ECG recordings of 376 cardiac arrest patients from three European areas were analysed. Ten features in the time and frequency domain derived from different sub-bands of the initial VF ECG (n=127) were evaluated. The correlation between VF ECG features and cardiac arrest times was investigated using Pearson's correlation coefficient in a subset of 40 patients with reliably estimated downtimes and artefact-free initial VF tracings. No significant correlation (p<.05) between any of the VF ECG features and downtime could be found. The duration of cardiac arrest could not be estimated reliably from human VF ECG single feature analysis.     

Research priorities for parenting and child health: a Delphi study

AIM: This paper is a report of a study to identify research priorities of clinical staff working with families at a Western Australian centre for parenting. BACKGROUND: Australian centres for parenting focus on children's needs while working in partnership with parents, families and their communities. These agencies incorporate primary healthcare strategies in their unique approach with families. Clinicians' research priorities at these centres have not been explored in an Australian context. METHOD: In 2005, a Delphi study was conducted in which clinicians were asked to provide a list of five important issues relating to care provided to children, parents and their families. Research topics identified were then ranked for their importance to the family and clinicians. Finally, the top 10 research topics were ranked for priority. FINDINGS: In round 1, 148 research topics were identified. Thirty-six topics were removed, due to the availability of existing evidence. Content analysis was used to collapse statements into 26 research questions, which were further classified into seven categories: parenting issues; sleep and settling issues; postnatal depression; evaluation and impact of programmes; staffing issues; centre marketing services and others. Issues relating to sleep and settling and postnatal depression were rated as top research priorities. CONCLUSION: The priorities of clinicians working with families provide research direction for this Western Australian centre and potentially other centres in Australia and similar settings elsewhere in the world. The Delphi approach in determining clinicians' perceptions of relevant research areas may be useful to direct research in other contexts.     

The role of Müller cell glucocorticoid signaling in diabetic retinopathy

Graefe's Archive for Clinical and Experimental Ophthalmology - Diabetic retinopathy (DR) is a sight-threatening complication associated with the highly prevalent diabetes disorder. Both the...     

Less Structured Movement Patterns Predict Severity of Positive Syndrome,Excitement, and Disorganization

Disorganized behavior is a key symptom of schizophrenia. The objective assessment of disorganized behavior is particularly challenging. Actigraphy has enabled the objective assessment of motor behavior in various settings. Reduced motor activity was associated with negative syndrome scores, but simple motor activity analyses were not informative on other symptom dimensions. The analysis of movement patterns, however, could be more informative for assessing schizophrenia symptom dimensions. Here, we use time series analyses on actigraphic data of 100 schizophrenia spectrum disorder patients. Actigraphy recording intervals were set at 2 s. Data from 2 defined 60-min periods were analyzed, and partial autocorrelations of the actigraphy time series indicated predictability of movements in each individual. Increased positive syndrome scores were associated with reduced predictability of movements but not with the overall amount of movement. Negative syndrome scores were associated with low activity levels but unrelated with predictability of movement. The factors disorganization and excitement were related to movement predictability but emotional distress was not. Thus, the predictability of objectively assessed motor behavior may be a marker of positive symptoms and disorganized behavior. This behavior could become relevant for translational research.Key words: schizophrenia, actigraphy, behavior, time series analysis, positive symptoms, negative symptoms     

Psychotropic medication in geriatric psychiatric patients: use and unreported use in relation to serum concentrations

Purpose

The aim of this observational study was to describe the type, number, and serum concentration levels of psychotropic drugs in elderly patients, on admission to a geriatric psychiatric inpatient unit. We further wanted to investigate the use and unreported use of psychotropic drugs by analyzing for a broad spectrum of drugs in the serum samples.

Methods

A total of 236 patients were included. Drug use, patient characteristics, and diagnoses were recorded, and serum analysis was performed for a total of 56 psychotropic drugs in 233 of the patients.

Results

Nine out of ten patients (88 %) used one or more psychotropic drugs on admission to hospital; the mean use was 2.8 (95 % confidence interval (CI) 2.6–2.9) drugs. In 25 patients (11 %), drugs reported used were not detected in serum. Unreported use of drugs (serum analysis revealing one or more drugs not reported) was found in 100 patients (43 %). This was more common in younger patients. Psychotropic polypharmacy (use of three or more psychotropic drugs) was found in 109 patients (47 %). Patients with a main diagnosis of affective disorder used the most psychotropic drugs.

Conclusions

Psychotropic drugs are commonly used among geriatric psychiatric patients on admission to hospital. Psychotropic polypharmacy is a major concern among these patients. There was considerable unreported use of drugs within this population, and a low threshold for a broader serum analysis for psychotropic drugs appears indicated.     

Reflux from the continent ileostomy reservoir

The reflux from the continent ileostomy reservoir was studied with radiologic and pressure recording techniques in ten patients. The contrast used was poly-iodine-styrene with a density of 0.8 to 1.1 gm/cm3. Reflux into the afferent loop was demonstrated in all patients at a filling volume of approximately 30 percent of the maximal volume capacity of the reservoir. The magnitude of reflux increased with the increasing volume of the reservoir contents and a rise in reservoir pressure. The reflux could temporarily be influenced by antiperistaltic or isoperistaltic motor activity in the afferent loop. Although no adverse effects were seen from the amount of reflux demonstrated in the present investigation, the finding of increasing reflux with increased fullness and intraluminal pressure of the reservoir would indicate that the reservoir should be emptied at regular intervals and before high pressures are built up.