Enhancing transduction of the liver by adeno-associated viral vectors

A number of distinct factors acting at different stages of the adeno-associated virus vector (AAV)-mediated gene transfer process were found to influence murine hepatocyte transduction. Foremost among these was the viral capsid protein. Self-complementary (sc) AAV pseudotyped with capsid from serotype 8 or rh.10 mediated fourfold greater hepatocyte transduction for a given vector dose when compared with vector packaged with AAV7 capsid. An almost linear relationship between vector dose and transgene expression was noted for all serotypes with vector doses as low as 1 x 10(7) vg per mouse (4 x 10(8) vg kg(-1)) mediating therapeutic levels of human FIX (hFIX) expression. Gender significantly influenced scAAV-mediated transgene expression, with twofold higher levels of expression observed in male compared with female mice. Pretreatment of mice with the proteasome inhibitor bortezomib increased scAAV-mediated hFIX expression from 4+/-0.6 to 9+/-2 microg ml(-1) in female mice, although the effect of this agent was less profound in males. Exposure of mice to adenovirus 10-20 weeks after gene transfer with AAV vectors augmented AAV transgene expression twofold by increasing the level of proviral mRNA. Hence, optimization of individual steps in the AAV gene transfer process can further enhance the potency of AAV-mediated transgene expression, thus increasing the probability of successful gene therapy.

The transition from medical student to doctor: perceptions of final year students and preregistration house officers related to expected learning outcomes

In this prospective qualitative study over 12 months, we evaluated the educational and clinical effectiveness of a new final year undergraduate programme in a London medical school (Guy's, King's and St Thomas'). A stratified sample of 17/360 final year students were interviewed four times, and the content was assessed against 32 amalgamated learning outcomes identified in 1997 in The New Doctor. At the beginning of the preregistration year, eight of the learning outcomes were already met, 10 partly, eight remained to be attained and for six, insufficient evidence existed. Preregistration house officers who have been through the final year student house officer programme expressed competence in many of the outcomes of the General Medical Council's New Doctor. The study identified areas such as prescribing where further developments are needed and will help in planning the new foundation programme.

A prospective, within-patient comparison between metal butterfly needles and Teflon cannulae in subcutaneous infusion of drugs to terminally ill hospice patients

We performed a prospective study of hospice in-patients requiring a syringe driver (SD), to determine the site duration and tolerability of metal butterfly needles compared to Teflon cannulae. Using patients as their own control, prescribed medications were divided equally between two SDs (Graseby MS16a), for delivery over 24 h. A butterfly infusion (Flosafer, 25 gauge) was connected to one SD and a Teflon cannula (Abbocath-T, 24 gauge), to the second. These were inserted subcutaneously (s.c.) on opposite sides of the body at comparable sites; oedematous, broken or painful sites were excluded. SD sites were examined at 4-hourly intervals. The study was terminated when both devices had required resiting. Needle and cannula times were compared using the Wilcoxon signed rank test. Thirty patients entered the study, 13 males and 17 females, mean age (standard deviation): 70 (11) years. Thirteen patients completed the study. Nine patients died and eight patients discontinued the study before both needle and cannula had been resited. All 30 patients are included in the analysis. The time from insertion to resiting of the cannula was significantly longer than the needle: P < 0.0002, median (range) 93.5 (22.8-263.5) h versus 42.8 (7.5-162.3) h, respectively. The cost of the needle versus cannula is 1.93 Pounds versus 2.51 Pounds, respectively. Teflon cannulae have a median life span twice that of metal butterfly needles and are a cost-effective alternative for administration of medications by s.c. infusion in terminally ill patients.

Cost-effectiveness of Interventions for Chronic Fatigue Syndrome or Myalgic Encephalomyelitis: A Systematic Review of Economic Evaluations

INTRODUCTION

Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) has profound quality of life and economic consequences for individuals, their family, formal services and wider society. Little is known about which therapeutic interventions are more cost-effective.

OBJECTIVE

A systematic review was carried out to identify and critically appraise the evidence on the cost-effectiveness of CFS/ME interventions.

METHODS

The review protocol was prespecified (PROSPERO: CRD42018118731). Searches were carried out across two databases-MEDLINE (1946-2020) and EMBASE (1974-2020). Additional studies were identified by searching reference lists. Only peer-reviewed journal articles of full economic evaluations examining CFS/ME interventions were included. Trial- and/or model-based economic evaluations were eligible. Data extraction and screening were carried out independently by two reviewers. The methodological quality of the economic evaluation and trial were assessed using the Consensus Health Economic Criteria checklist (CHEC-list) and Risk of Bias-2 (RoB-2) tool, respectively. A narrative synthesis was used to summarise the economic evidence for interventions for adults and children in primary and secondary care settings.

RESULTS

Ten economic evaluations, all based on data derived from randomised controlled trials, met our eligibility criteria. Cognitive behavioural therapy (CBT) was evaluated across five studies, making it the most commonly evaluated intervention. There was evidence from three trials to support CBT as a cost-effective treatment option for adults; however, findings on CBT were not uniform, suggesting that cost-effectiveness may be context-specific. A wide array of other interventions were evaluated in adults, including limited evidence from two trials supporting the cost effectiveness of graded exercise therapy (GET). Just one study assessed intervention options for children. Our review highlighted the importance of informal care costs and productivity losses in the evaluation of CFS/ME interventions.

CONCLUSIONS

We identified a limited patchwork of evidence on the cost-effectiveness of interventions for CFS/ME. Evidence supports CBT as a cost-effective treatment option for adults; however, cost-effectiveness may depend on the duration and frequency of sessions. Limited evidence supports the cost effectiveness of GET. Key weaknesses in the literature included small sample sizes and short duration of follow-up. Further research is needed on pharmacological interventions and therapies for children.

The clinical and educational experiences of pre-registration house officers in general practice

AIMS

To describe aspects of the clinical experience and educational supervision gained by pre-registration house officers (PRHOs) in general practice, and to relate these to the current General Medical Council (GMC) aims for general clinical training in general practice.

DESIGN

Qualitative evaluation, part of which involved semistructured interviews with 12 PRHOs who were experiencing a general practice rotation. Interviews were conducted at the beginning and the end of the pre-registration year, and following return to hospital work after completion of the general practice placement.

SETTINGS

Three teaching hospitals, two district general hospitals and six general practices in south-east England.

PARTICIPANTS

12 PRHOs who were involved in rotations incorporating a general practice placement.

RESULTS

To varying degrees, the GMC aims for training in general practice were met for all the participants. All PRHOs recognized the value of the clinical experience and educational supervision they received in general practice. They particularly valued aspects such as having an individual training programme based on their own needs, and the interlinking of theory and practice, which aided learning. Most felt that having responsibility for their own patients acted as an important incentive for learning, and in general, PRHOs appreciated having the time to learn which general practice allowed.

CONCLUSIONS

For the majority of PRHOs, the time spent in general practice was seen as a positive clinical and educational experience. In a variety of ways, the general practice placement encouraged PRHOs to develop the self-directed learning skills seen as essential to the lifelong learning advocated by the GMC. A number of recommendations are made to help improve the integration of the hospital and general practice components of these rotations.

Systematic review of the methods used in economic evaluations of targeted physical activity and sedentary behaviour interventions

The burden of noncommunicable diseases (NCD) on health systems worldwide is substantial. Physical inactivity and sedentary behaviour are major risk factors for NCD. Previous attempts to understand the value for money of preventative interventions targeting physically inactive individuals have proved to be challenging due to key methodological challenges associated with the conduct of economic evaluations in public health. A systematic review was carried out across six databases (Medline, SPORTSDiscus, EconLit, PsychINFO, NHS EED, HTA) along with supplementary searches. The review examines how economic evaluations published between 2009-March 2017 have addressed methodological challenges with the aim of bringing to light examples of good practice for future studies. Fifteen economic evaluations from four high-income countries were retrieved; there is a dearth of studies targeting sedentary behaviour as an independent risk factor from physical activity. Comparability of studies from the healthcare and societal perspectives were limited due to analysts' choice in cost categories, valuation technique and time horizon differing substantially. The scarcity of and inconsistencies across economic evaluations for these two behaviours have exposed a mismatch between calls for more preventative action to tackle NCD and the lack of information available on how resources may be optimally allocated in practice. Consequently, this paper offers a table of recommendations on how future studies can be improved.

Pre-registration house officers in general practice: the views of GP trainers

BACKGROUND

Recent changes have led to an upsurge of interest in pre-registration rotations in general practice. In 1998, a national pilot programme of >40 new rotations incorporating general practice was implemented.

OBJECTIVE

The aim of this study was to explore the experiences of GPs involved in the four pilot rotations established in South Thames region.

METHODS

Semi-structured interviews were conducted with trainers and partners.

RESULTS

The supervisory workload for pre-registration house officers (PRHOs) was much greater than that required by registrars. All GPs felt that increased remuneration was important for the future viability of the scheme. The majority of GPs remained supportive of the scheme, although a minority were concerned about the value of the experience gained by PRHOs. There were a few instances in which inadequacies in patient management had to be dealt with subsequently by trainers. The supervisory implications of such events will need to be addressed.

CONCLUSION

This significant development in medical education has important implications for GPs and their patients which need further exploration through long-term evaluations.

The doctor-patient relationship: from undergraduate assumptions to pre-registration reality

OBJECTIVES

To describe the ways in which the doctor-patient relationship experienced by newly qualified pre-registration house officers (PRHOs) differed from their undergraduate expectations.

DESIGN

Qualitative study in which in-depth semistructured interviews were carried out with each PRHO within 4-6 weeks of the start of their first job.

SETTING

Three teaching hospitals, three district general hospitals and four general practices in south-east England.

PARTICIPANTS

24 newly qualified PRHOs.

RESULTS

A number of differences were identified by PRHOs. These were caused in part by the impact of factors such as the shortage of time, which could lead to emotional 'blunting'. Some PRHOs were changing their ideas about what constitutes a 'good' doctor, and were redefining the meaning of a 'professional' relationship. The relationships of PRHOs with patients were also affected by the attitudes of their senior colleagues. For example, where PRHOs tried to maintain a patient-centred relationship, they could be identified by colleagues as working too slowly. PRHOs working in general practice were able to utilize and improve their communication skills with patients, but found it difficult to transfer these skills back into the hospital setting.

CONCLUSIONS

Despite receiving substantial undergraduate education on how best to communicate with patients, a variety of factors conspired to prevent hospital-based PRHOs from utilizing this information. Building on these findings, a number of recommendations are made to help improve practice.

Differences in Corticosterone Release Rates of Larval Spring Salamanders (Gyrinophilus porphyriticus) in Response to Native Fish Presence

Invasive fish predators are an important factor causing amphibian declines and may have direct and indirect effects on amphibian survival. For example, early non-lethal exposure to these stressors may reduce survival in later life stages, especially in biphasic species. In amphibians, the glucocorticoid hormone corticosterone is released by the hypothalamo-pituitary-interrenal axis (HPI), as an adaptive physiological response to environmental stressors. The corticosterone response (baseline and response to acute stressors) is highly flexible and context dependent, and this variation can allow individuals to alter their phenotype and behavior with environmental changes, ultimately increasing survival. We sampled larvae of the spring salamander (Gyrinophilus porphyriticus) from two streams that each contained predatory brook trout (Slavelinus fontinalis) in the lower reaches and no predatory brook trout in the upper reaches. We measured baseline and stress-induced corticosterone release rates of larvae from the lower and upper reaches using a non-invasive water-borne hormone assay. We hypothesized that corticosterone release rates would differ between larvae from fish-present reaches and larvae from fish-free reaches. We found that baseline and stressor-induced corticosterone release rates were downregulated in larvae from reaches with fish predators. These results indicate that individuals from reaches with predatory trout are responding to fish predators by downregulating corticosterone while maintaining an active HPI axis. This may allow larvae more time to grow before metamorphosing, while also allowing them to physiologically respond to novel stressors. However, prolonged downregulation of corticosterone release rates can impact growth in post-metamorphic individuals.

Pre-registration rotations into general practice: the concerns of pre-registration house officers and the views of hospital consultants

AIMS

To explore the concerns of pre-registration house officers (PRHOs) and the views of hospital consultants in relation to pre-registration rotations with a general practice component.

METHOD

As part of a larger qualitative study evaluating how a group of 24 PRHOs learn in hospital and primary care settings, face-to-face semistructured interviews were conducted with the PRHOs, and semistructured telephone interviews with the PRHOs' educational supervisors were carried out.

RESULTS

The interviews with the PRHOs highlighted their concerns about how consultants might view PRHO rotations into general practice. However, the majority of consultants interviewed recognized and valued specific aspects of the experience to be gained by PRHOs in general practice, including the relationship between primary and secondary care; communications skills; specific clinical skills, and an understanding of the natural course of illnesses. The experience was seen as valuable for PRHOs considering either a general practice or a hospital career. Of the 17 consultants, 10 were also confident that 4-month placements in surgery and medicine would give PRHOs adequate experience in either specialty, providing the placements were sufficiently busy.

CONCLUSIONS

Medical school deans and medical students considering PRHO rotations with a general practice component can be encouraged by the fact that, in this small study, the majority of hospital consultants interviewed valued the specific experience offered by these rotations, and felt that adequate medical and surgical experience could be gained in busy 4-month hospital placements.

Proper understanding of recurrent stress urinary incontinence treatment in women (PURSUIT): a randomised controlled trial of endoscopic and surgical treatment

BACKGROUND

Women with stress urinary incontinence (SUI) experience urine leakage with physical activity. Currently, the interventional treatments for SUI are surgical, or endoscopic bulking injection(s). However, these procedures are not always successful, and symptoms can persist or come back after treatment, categorised as recurrent SUI. There are longstanding symptoms and distress associated with a failed primary treatment, and currently, there is no consensus on how best to treat women with recurrent, or persistent, SUI.

METHODS

A two-arm trial, set in at least 20 National Health Service (NHS) urology and urogynaecology referral units in the UK, randomising 250 adult women with recurrent or persistent SUI 1:1 to receive either an endoscopic intervention (endoscopic bulking injections) or a standard NHS surgical intervention, currently colposuspension, autologous fascial sling or artificial urinary sphincter. The aim of the trial is to determine whether surgical treatment is superior to endoscopic bulking injections in terms of symptom severity at 1 year after randomisation. This primary outcome will be measured using the patient-reported International Consultation on Incontinence Questionnaire - Urinary Incontinence - Short Form (ICIQ-UI-SF). Secondary outcomes include assessment of longer-term clinical impact, improvement of symptoms, safety, operative assessments, sexual function, cost-effectiveness and an evaluation of patients' and clinicians' views and experiences of the interventions.

DISCUSSION

There is a lack of high-quality, randomised, scientific evidence for which treatment is best for women presenting with recurrent SUI. The PURSUIT study will benefit healthcare professionals and patients and provide robust evidence to guide further treatment and improve symptoms and quality of life for women with this condition.

TRIAL REGISTRATION

International Standard Randomised Controlled Trials Number (ISRCTN) registry ISRCTN12201059. Registered on 09 January 2020.

Pre-registration house officer rotations incorporating general practice: does the order of rotation matter?

CONTEXT

In relation to pre-registration house officer (PRHO) rotations incorporating general practice, previous research has recommended that where possible, no PRHO should undertake general practice as the first placement, because of the difficulties encountered. It was recognized that logistically, this could make such schemes almost unworkable. Within the context of a larger qualitative evaluation comparing how 24 PRHOs learned in hospital and general practice settings, the issue of rotation order was explored.

METHODS

In-depth semistructured interviews were conducted with the 12 PRHOs who were involved in general practice rotations. They were interviewed at the beginning and end of the PRHO year, and following their return to hospital work after the general practice placement.

RESULTS

Each rotation order had both advantages and disadvantages, with no particular rotation order being obviously better or worse for the PRHOs involved.

CONCLUSIONS

This small qualitative evaluation has highlighted a number of advantages and disadvantages specific to each rotation order, and makes some practical recommendations to help alleviate the problems encountered. It is important that future evaluations of similar schemes consider this issue, as there are conflicting reports about the significance of the rotation order.

Stage-Specific Demographic Effects of Hydrologic Variation in a Stream Salamander

AbstractWe lack a strong understanding of how organisms with complex life histories respond to climate variation. Many stream-associated species have multistage life histories that are likely to influence the demographic consequences of floods and droughts. However, tracking stage-specific demographic responses requires high-resolution, long-term data that are rare. We used 8 years of capture-recapture data for the headwater stream salamander Gyrinophilus porphyriticus to quantify the effects of flooding and drying magnitude on stage-specific vital rates and population growth. Drying reduced larval recruitment but increased the probability of metamorphosis (i.e., adult recruitment). Flooding reduced adult recruitment but had no effect on larval recruitment. Larval and adult survival declined with flooding but were unaffected by drying. Annual population growth rates (λ) declined with flooding and drying. Lambda also declined over the study period (2012-2021), although mean λ was 1.0 over this period. Our results indicate that G. porphyriticus populations are resilient to hydrologic variation because of compensatory effects on recruitment of larvae versus adults (i.e., reproduction vs. metamorphosis). Complex life cycles may enable this resilience to climate variation by creating opportunities for compensatory demographic responses across stages. However, more frequent and intense hydrologic variation in the latter half of this study contributed to a decline in λ over time, suggesting that increasing environmental variability poses a threat even when demographic compensation occurs.

Individual growth rates and size at metamorphosis increase with watershed area in a stream salamander

A fundamental goal of ecology is to understand how the physical environment influences intraspecific variability in life history and, consequently, fitness. In streams, discharge and associated habitat conditions change along a continuum from intermittency to permanence: Headwater streams typically have smaller watersheds and are thus more prone to drying than higher-order streams with larger watersheds and more consistent discharge. However, few empirical studies have assessed life history and associated population responses to this continuum in aquatic organisms. We tested the prediction that individual growth, rate of development, and population growth increase with watershed area in the long-lived stream salamander Gyrinophilus porphyriticus, where we use watershed area as a proxy for hydrologic intermittence. To address this hypothesis, we used 8 years of mark-recapture data from 53 reaches across 10 headwater streams in New Hampshire, USA. Individual growth rates and mean size at metamorphosis increased with watershed area for watersheds from 0.12 to 1.66 km2 . Population growth rates increased with watershed area; however, this result was not statistically significant at our sample size. Mean age of metamorphosis did not vary across watershed areas. Lower individual growth rates and smaller sizes at metamorphosis likely contributed to reduced lifetime fecundity and population growth in reaches with the smallest watershed areas and highest vulnerability to drought. These responses suggest that as droughts increase due to climate change, headwater specialists in hydrologically intermittent environments will experience a reduction in fitness due to smaller body sizes or other growth-related mechanisms.

PRHOs in primary care: what is happening out there?

Preregistration house officer (PRHO) placements in general practice were introduced throughout Britain in August 1998. This paper describes an evaluation of PRHOs in primary care rotations in South Thames during 1998-99. There are important messages for both educational supervisors and undergraduates considering a PRHO in primary care rotation.

Outbreeding reduces survival during metamorphosis in a headwater stream salamander

Assessing direct fitness effects of individual genetic diversity is challenging due to the intensive and long-term data needed to quantify survival and reproduction in the wild. But resolving these effects is necessary to determine how inbreeding and outbreeding influence eco-evolutionary processes. We used 8 years of capture-recapture data and single nucleotide polymorphism genotypes for 1906 individuals to test for effects of individual heterozygosity on stage-specific survival probabilities in the salamander Gyrinophilus porphyriticus. The life cycle of G. porphyriticus includes an aquatic larval stage followed by metamorphosis into a semi-aquatic adult stage. In our study populations, the larval stage lasts 6-10 years, metamorphosis takes several months, and lifespan can reach 20 years. Previous studies showed that metamorphosis is a sensitive life stage, leading us to predict that fitness effects of individual heterozygosity would occur during metamorphosis. Consistent with this prediction, monthly probability of survival during metamorphosis declined with multi-locus heterozygosity (MLH), from 0.38 at the lowest MLH (0.10) to 0.06 at the highest MLH (0.38), a reduction of 84%. Body condition of larvae also declined significantly with increasing MLH. These relationships were consistent in the three study streams. With evidence of localised inbreeding within streams, these results suggest that outbreeding disrupts adaptations in pre-metamorphic and metamorphic individuals to environmental gradients along streams, adding to evidence that headwater streams are hotspots of microgeographic adaptation. Our results also underscore the importance of incorporating life history in analyses of the fitness effects of individual genetic diversity and suggest that metamorphosis and similar discrete life stage transitions may be critical periods of viability selection.

Source-sink dynamics within a complex life history

Source-sink patch dynamics occur when movement from sources stabilizes sinks by compensating for low local vital rates. The mechanisms underlying source-sink dynamics may be complicated in species that undergo transitions between discrete life stages, particularly when stages have overlapping habitat requirements and similar movement abilities. In these species, for example, the demographic effects of movement by one stage may augment or offset the effects of movement by another stage. We used a stream salamander system to investigate patch dynamics within this form of complex life history. Specifically, we tested the hypothesis that the salamander Gyrinophilus porphyriticus experiences source-sink dynamics in riffles and pools, the dominant geomorphic patch types in headwater streams. We estimated stage-specific survival probabilities in riffles and pools and stage-specific movement probabilities between the two patch types using 8 years of capture-recapture data on 4491 individuals, including premetamorphic larvae and postmetamorphic adults. We then incorporated survival and movement probabilities into a stage-structured, two-patch model to determine the demographic interactions between riffles and pools. Monthly survival probabilities of both stages were higher in pools than in riffles. Larvae were more likely to move from riffles to pools, but adults were more likely to move from pools to riffles, despite experiencing much lower survival in riffles. In simulations, eliminating interpatch movements by both stages indicated that riffles are sinks that rely on immigration from pools for stability. Allowing only larvae to move stabilized both patch types, but allowing only adults to move destabilized pools due to the demographic cost of adult emigration. These results indicated that larval movement not only stabilizes riffles, but also offsets the destabilizing effects of maladaptive adult movement. Similar patch dynamics may emerge in any structured population in which movement and local vital rates differ by age, size, or stage. Addressing these forms of internal demographic structure in patch dynamics analyses will help to refine and advance general understanding of spatial ecology.