Intravenous thrombolysis for multi-ethnic Asians with acute ischaemia stroke in Malaysian public primary stroke centres versus acute stroke ready hospitals: Comparison of real-world clinical outcomes

INTRODUCTION

Intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator is beneficial in acute ischaemic stroke (AIS). We aim to compare the realworld clinical outcomes and service efficiency of IVT in Malaysian primary stroke centres (PSCs) versus acute stroke ready hospitals (ASRHs).

MATERIALS AND METHODS

We conducted a multi-centre cohort study involving 5 PSCs and 7 ASRHs in Malaysia. Through review of medical records of AIS patients who received IVT from 01 January 2014 to 30 June 2021, real-world data was extracted for analysis. Univariate and multivariate regression models were employed to evaluate the role of PSCs versus ASRHs in post-IVT outcomes and complications. Statistical significance was set at p<0.05.

RESULTS

A total of 313 multi-ethnic Asians, namely 231 from PSCs and 82 from ASRHs, were included. Both groups were comparable in baseline demographic, clinical, and stroke characteristics. The efficiency of IVT delivery (door-toneedle time), functional outcomes (mRS at 3 months post- IVT), and rates of adverse events (intracranial haemorrhages and mortality) following IVT were comparable between the 2 groups. Notably, 46.8% and 48.8% of patients in PSCs and ASRHs group respectively (p=0.752) achieved favourable functional outcome (mRS≤1 at 3 months post-IVT). Regression analyses demonstrated that post-IVT functional outcomes and adverse events were independent of the role of PSCs or ASRHs.

CONCLUSION

Our study provides real-world evidence which suggests that IVT can be equally safe, effective, and efficiently delivered in ASRHs. This may encourage the establishment of more ASRHs to extend the benefits of IVT to a greater proportion of stroke populations and enhance the regional stroke care.

Dirofilariasis mouse models for heartworm preclinical research

Introduction

Dirofilariasis, including heartworm disease, is a major emergent veterinary parasitic infection and a human zoonosis. Currently, experimental infections of cats and dogs are used in veterinary heartworm preclinical drug research.

Methods

As a refined alternative in vivo heartworm preventative drug screen, we assessed lymphopenic mouse strains with ablation of the interleukin-2/7 common gamma chain (γc) as susceptible to the larval development phase of Dirofilaria immitis.

Results

Non-obese diabetic (NOD) severe combined immunodeficiency (SCID)γc^-/- (NSG and NXG) and recombination-activating gene (RAG)2^-/-γc^-/- mouse strains yielded viable D. immitis larvae at 2-4 weeks post-infection, including the use of different batches of D. immitis infectious larvae, different D. immitis isolates, and at different laboratories. Mice did not display any clinical signs associated with infection for up to 4 weeks. Developing larvae were found in subcutaneous and muscle fascia tissues, which is the natural site of this stage of heartworm in dogs. Compared with in vitro-propagated larvae at day 14, in vivo-derived larvae had completed the L4 molt, were significantly larger, and contained expanded Wolbachia endobacteria titres. We established an ex vivo L4 paralytic screening system whereby assays with moxidectin or levamisole highlighted discrepancies in relative drug sensitivities in comparison with in vitro-reared L4 D. immitis. We demonstrated effective depletion of Wolbachia by 70%-90% in D. immitis L4 following 2- to 7-day oral in vivo exposures of NSG- or NXG-infected mice with doxycycline or the rapid-acting investigational drug, AWZ1066S. We validated NSG and NXG D. immitis mouse models as a filaricide screen by in vivo treatments with single injections of moxidectin, which mediated a 60%-88% reduction in L4 larvae at 14-28 days.

Discussion

Future adoption of these mouse models will benefit end-user laboratories conducting research and development of novel heartworm preventatives via increased access, rapid turnaround, and reduced costs and may simultaneously decrease the need for experimental cat or dog use.

Using Normalization Process Theory as a Practical Tool Across the Life Course of a Qualitative Research Project

Drawing on work that aimed to understand factors influencing experience of and engagement with the National Health Service (NHS) Health Check Program, this article discusses how Normalization Process Theory was used throughout the life course of a research project. As a relatively new theory, Normalization Process Theory is still being refined and much work undertaken to develop interactive tools and "test" the utility of it. Although there is little published critique of the theory, two main issues have arisen in the literature: (a) difficulties ensuring interpretation of constructs are congruent to the original theory and (b) the intensity of translation work to contextualize the theory to individual settings. These issues are explored in this article by examining the processes undertaken to translate Normalization Process Theory so that it was usable to shape a qualitative research project from design to analysis and interpretation.

Simulated fate of catchment-derived sediment on the Great Barrier Reef shelf

Numerical experiments using a 3D model of fine sediment transport in the Great Barrier Reef region indicate deposition of the bulk mass of catchment sediments from river plumes within a few tens of kilometres from river mouths. A very fine fraction of easily resuspended catchment sediment has a capacity to propagate over much greater distances reaching out into the mid-shelf and outer-shelf regions. The model suggests such particles, instrumental to the development of low density flocs in the marine environment, can play a critical role in altering optical properties of water masses over the shelf during wet years. The mid-term (4 year) impact of Great Barrier Reef catchments on the probability of suspended sediment concentration exceeding the ecologically significant trigger value of 2 mg/L is confined to inshore regions adjacent to river mouth locations.

Carotid Bulb Webs as a Cause of "Cryptogenic" Ischemic Stroke

BACKGROUND AND PURPOSE

Carotid webs are intraluminal shelf-like filling defects at the carotid bulb with recently recognized implications in patients with recurrent ischemic stroke. We sought to determine whether carotid webs are an under-recognized cause of "cryptogenic" ischemic stroke and to estimate their prevalence in the general population.

MATERIALS AND METHODS

A retrospective review of neck CTA studies in young patients with cryptogenic stroke over the past 6 years (n = 33) was performed to determine the prevalence of carotid webs compared with a control group of patients who received neck CTA studies for reasons other than ischemic stroke (n = 63).

RESULTS

The prevalence of carotid webs in the cryptogenic stroke population was 21.2% (95% CI, 8.9%-38.9%). Patients with symptomatic carotid webs had a mean age of 38.9 years (range, 30-48 years) and were mostly African American (86%) and women (86%). In contrast, only 1.6% (95% CI, 0%-8.5%) of patients in the control group demonstrated a web. Our findings demonstrate a statistically significant association between carotid webs and ischemic stroke (OR = 16.7; 95% CI, 2.78-320.3; P = .01).

CONCLUSIONS

Carotid webs exhibit a strong association with ischemic stroke, and their presence should be suspected in patients lacking other risk factors, particularly African American women.

Intracranial Applications of MR Imaging-Guided Focused Ultrasound

Initially used in the treatment of prostate cancer and uterine fibroids, the role of focused ultrasound has expanded as transcranial acoustic wave distortion and other limitations have been overcome. Its utility relies on focal energy deposition via acoustic wave propagation. The duty cycle and intensity of focused ultrasound influence the rate of energy deposition and result in unique physiologic and biomechanical effects. Thermal ablation via high-intensity continuous exposure generates coagulative necrosis of tissues. High-intensity, pulsed application reduces temporally averaged energy deposition, resulting in mechanical effects, including reversible, localized BBB disruption, which enhances neurotherapeutic agent delivery. While the precise mechanisms remain unclear, low-intensity, pulsed exposures can influence neuronal activity with preservation of cytoarchitecture. Its noninvasive nature, high-resolution, radiation-free features allow focused ultrasound to compare favorably with other modalities. We discuss the physical characteristics of focused ultrasound devices, the biophysical mechanisms at the tissue level, and current and emerging applications.

The entrapped and unravelled coronary wire

No abstract available.

Using interactive workshops to prompt knowledge exchange: a realist evaluation of a knowledge to action initiative

INTRODUCTION

Interactive workshops are often the default mechanism for sharing knowledge across professional and sector boundaries; yet we understand little about if, and how, they work. Between 2009 and 2011, the Research to Reality programme in North East England ran eight stand-alone facilitated multi-agency workshops focused on priority public health issues. Local authorities, the health service, and academe collaborated on the programme to share latest evidence and best practice

METHODS

A realist evaluation asked the overarching question 'what worked where, for whom, and under what conditions' regarding the knowledge exchange (KE) mechanisms underpinning any changes. Data were collected from fifty-one interviews, six observations, and analysis of programme documentation.

RESULTS

191 delegates attended (local authority 46%, NHS 24%, academia 22%, third sector 6%, other 2%). The programme theory was that awareness raising and critical discussion would facilitate ownership and evidence uptake. KE activity included: research digests, academic and senior practitioner presentations, and facilitated round-table discussions. Joint action planning was used to prompt informed follow-up action. Participants valued the digests, expert input, opportunities for discussion, networking and 'space to think'. However, within a few months, sustainability was lost. There was no evidence of direct changes to practice. Multiple barriers to research utilization emerged.

DISCUSSION

The findings suggest that in pressured contexts exacerbated by structural reform providing evidence summaries, input from academic and practice experts, conversational spaces and personal action planning are necessary to create enthusiasm on the day, but are insufficient to prompt practice change in the medium term. The findings question makes assumptions about the instrumental, linear use of knowledge and of change focused on individuals as a driver for organizational change. Delegates' views of 'what would work' are shared. Mechanisms that would enhance interactive formats are discussed.

Influences on self-evaluation during a clinical skills programme for nurses

Education has moved from teacher to student-centred practices. Increasing emphasis is placed on 'life-long' learning in the context of a rapidly changing knowledge base. Self-evaluation is seen as one strategy to facilitate student-centred continuous professional development. The literature, however, suggests that learners' ability to self-assess is mixed, and little is known regarding how students perform self-assessment. This study focussed on senior nurses undertaking a scenario-based clinical skills course. Learners were asked to self-evaluate several times during the course. This research explored the influences on using the self-evaluation exercise. The study drew upon grounded theory methodology and was influenced by constructionist and postmodernist theories. Three methods of data collection were used: semi-structured interviews, observation of supervision sessions and recording of the numerical self-evaluation ratings. Multiple interviews with students (n = 14) and the educational supervisor (n = 1) were conducted. Thematic analysis and data collection were conducted iteratively. The study found that feeling confident and stating that confidence were not necessarily the same. Feeling confident was complex, influenced by changing perceptions of clinical skills and credibility. Changing frames of reference were used to judge feelings of confidence. Stating confidence appeared to be socially negotiated, influenced by social acceptability considerations such as modesty and the need to show progress over time. The discourses of empowerment and surveillance were influential and self-evaluation is discussed using Foucault's theory of governmentality, illustrating how learners can be both empowered and controlled through self-evaluation. Further consideration of the socially constructed nature of self-evaluations would benefit both educational practice and future research.

Mentoring for NHS doctors: perceived benefits across the personal-professional interface

OBJECTIVE

To investigate NHS doctors' perceived benefits of being involved in mentoring schemes and to explore the overlaps and relationships between areas of benefit.

DESIGN

Extended qualitative analysis of a multi-site interview study following an interpretivist approach.

SETTING

Six NHS mentoring schemes across England.

MAIN OUTCOME MEASURES

Perceived benefits.

RESULTS

While primary analysis resulted in lists of perceived benefits, the extended analysis revealed three overarching areas: professional practice, personal well-being and development. Benefits appear to go beyond a doctor's professional role to cross the personal-professional interface. Problem solving and change management seem to be key processes underpinning the raft of personal and professional benefits reported. A conceptual map was developed to depict these areas and relationships. In addition secondary analysis suggests that in benefitting one area mentoring may lead to consequential benefits in others.

CONCLUSIONS

Prior research into mentoring has mainly taken place in a single health care sector. This multi-site study suggests that the perceived benefits of involvement in mentoring may cross the personal/professional interface and may override organizational differences. Furthermore the map developed highlights the complex relationships which exist between the three areas of professional practice, personal wellbeing and personal and professional development. Given the consistency of findings across several studies it seems probable that organizations would be strengthened by doctors who feel more satisfied and confident in their professional roles as a result of participation in mentoring. Mentoring may have the potential to take us beyond individual limits to greater benefits and the conceptual map may offer a starting point for the development of outcome criteria and evaluation tools for mentoring schemes.

Nasogastric feeding in severe acute pancreatitis may be practical and safe

BACKGROUND

Severe acute pancreatitis may be protracted and some form of nutritional support is frequently required to maintain the patient's nutritional status. Recent work has suggested that enteral feeding via a jejunal route of delivery may reduce the magnitude of the inflammatory response. Insertion of nasojejunal (NJ) tubes in the patient with severe acute pancreatitis involves both delay and inconvenience. We undertook a prospective, feasibility study to assess the safety and practicability of nasogastric (NG) feeding in patients with severe acute pancreatitis.

PATIENTS AND METHODS

Twenty-six patients with objective evidence of severe acute pancreatitis received nasogastric feeding within 48 h of admission to our unit.

RESULTS

Etiology was identified as cholelithiasis (18 patients), ethanol (5), and miscellaneous (3). The median Glasgow score was 4 (range 2-7), APACHE II score 10 (4-28), and C-reactive protein concentration 286 mg/L (79-469). Fifteen patients had pancreatic and/or peripancreatic necrosis. Eleven patients developed severe organ failure, necessitating ventilatory support. Six developed multiple organ system failure, requiring inotropic support and/or renal dialysis. There were four deaths (15.3%). Nine patients underwent early, and nine late, ERCP, respectively; six necrosectomy (5 proven infected necrosis, 1 continued deterioration despite maximal support) and 4 patients internal drainage of a pseudocyst. The feed was well-tolerated in 22 patients. In 3 patients gastric stasis proved troublesome. There was no evidence of clinical or biochemical deterioration on commencing nasogastric feeding.

CONCLUSION

It would appear that early NG feeding is usually possible in severe acute pancreatitis. In most patients it appears safe, well-tolerated, and worthy of further study.

ENCORE: the effect of nutrient enrichment on coral reefs. Synthesis of results and conclusions

Coral reef degradation resulting from nutrient enrichment of coastal waters is of increasing global concern. Although effects of nutrients on coral reef organisms have been demonstrated in the laboratory, there is little direct evidence of nutrient effects on coral reef biota in situ. The ENCORE experiment investigated responses of coral reef organisms and processes to controlled additions of dissolved inorganic nitrogen (N) and/or phosphorus (P) on an offshore reef (One Tree Island) at the southern end of the Great Barrier Reef, Australia. A multi-disciplinary team assessed a variety of factors focusing on nutrient dynamics and biotic responses. A controlled and replicated experiment was conducted over two years using twelve small patch reefs ponded at low tide by a coral rim. Treatments included three control reefs (no nutrient addition) and three + N reefs (NH4Cl added), three + P reefs (KH2PO4 added), and three + N + P reefs. Nutrients were added as pulses at each low tide (ca twice per day) by remotely operated units. There were two phases of nutrient additions. During the initial, low-loading phase of the experiment nutrient pulses (mean dose = 11.5 microM NH4+; 2.3 microM PO4(-3)) rapidly declined, reaching near-background levels (mean = 0.9 microM NH4+; 0.5 microM PO4(-3)) within 2-3 h. A variety of biotic processes, assessed over a year during this initial nutrient loading phase, were not significantly affected, with the exception of coral reproduction, which was affected in all nutrient treatments. In Acropora longicyathus and A. aspera, fewer successfully developed embryos were formed, and in A. longicyathus fertilization rates and lipid levels decreased. In the second, high-loading, phase of ENCORE an increased nutrient dosage (mean dose = 36.2 microM NH4+; 5.1 microM PO4(-3)) declining to means of 11.3 microM NH4+ and 2.4 microM PO4(-3) at the end of low tide) was used for a further year, and a variety of significant biotic responses occurred. Encrusting algae incorporated virtually none of the added nutrients. Organisms containing endosymbiotic zooxanthellae (corals and giant clams) assimilated dissolved nutrients rapidly and were responsive to added nutrients. Coral mortality, not detected during the initial low-loading phase, became evident with increased nutrient dosage, particularly in Pocillopora damicornis. Nitrogen additions stunted coral growth, and phosphorus additions had a variable effect. Coral calcification rate and linear extension increased in the presence of added phosphorus but skeletal density was reduced, making corals more susceptible to breakage. Settlement of all coral larvae was reduced in nitrogen treatments, yet settlement of larvae from brooded species was enhanced in phosphorus treatments. Recruitment of stomatopods, benthic crustaceans living in coral rubble, was reduced in nitrogen and nitrogen plus phosphorus treatments. Grazing rates and reproductive effort of various fish species were not affected by the nutrient treatments. Microbial nitrogen transformations in sediments were responsive to nutrient loading with nitrogen fixation significantly increased in phosphorus treatments and denitrification increased in all treatments to which nitrogen had been added. Rates of bioerosion and grazing showed no significant effects of added nutrients. ENCORE has shown that reef organisms and processes investigated in situ were impacted by elevated nutrients. Impacts were dependent on dose level, whether nitrogen and/or phosphorus were elevated and were often species-specific. The impacts were generally sub-lethal and subtle and the treated reefs at the end of the experiment were visually similar to control reefs. Rapid nutrient uptake indicates that nutrient concentrations alone are not adequate to assess nutrient condition of reefs. Sensitive and quantifiable biological indicators need to be developed for coral reef ecosystems. The potential bioindicators identified in ENCORE should be tested in future research on coral reef/nutrient interactions. Synergistic and cumulative effects of elevated nutrients and other environmental parameters, comparative studies of intact vs. disturbed reefs, offshore vs. inshore reefs, or the ability of a nutrient-stressed reef to respond to natural disturbances require elucidation. An expanded understanding of coral reef responses to anthropogenic impacts is necessary, particularly regarding the subtle, sub-lethal effects detected in the ENCORE studies.

Use of a telemetered dispensing system for controlling nutrient additions to experimental patch reefs in the ENCORE study at One Tree Island, Great Barrier Reef, Australia

A telemetrically controlled system was developed to add nutrients automatically to experimental patch reefs in a remote marine environment. The experiment, called ENCORE, was done in the lagoon of One Tree Island, a remote research station at the southern end of the Great Barrier Reef. Nutrient dispensing units (NDUs), moored adjacent to patch reefs in the lagoon, were telemetrically linked to a base station on the island. The base station, about 3 km away from the furthest NDU, consisted of a dedicated computer, controller and radio transmitter, which relayed coded signals to a radio receiver mounted on each NDU. This activated a solenoid valve to discharge a measured quantity of concentrated nutrient solution from a measuring chamber using compressed air from a SCUBA tank. The solution was discharged through 4-8 PVC outlets into the basins of the patch reefs to allow thorough mixing. The base station interrogated each NDU to find out if the operation had been successful and stored the information on disk to provide a daily log of operations. Nutrient samples taken within the patch reefs demonstrated that calculated initial mean concentrations of 2 micrograms-at PO4-P l-1 and 10 micrograms-at NH4-N l-1 were achieved. The system we have developed can be used in many situations where regular perturbations need to be introduced to aquatic ecosystems. It uses state-of-the-art technology, yet all components are commercially readily available and relatively inexpensive. Detailed specifications and drawings are available from the Great Barrier Reef Marine Park Authority.

Nasogastric feeding in severe acute pancreatitis may be practical and safe

BACKGROUND

Severe acute pancreatitis may be protracted and some form of nutritional support is frequently required to maintain the patient's nutritional status. Recent work has suggested that enteral feeding via a jejunal route of delivery may reduce the magnitude of the inflammatory response. Insertion of nasojejunal (NJ) tubes in the patient with severe acute pancreatitis involves both delay and inconvenience. We undertook a prospective, feasibility study to assess the safety and practicability of nasogastric (NG) feeding in patients with severe acute pancreatitis.

PATIENTS AND METHODS

Twenty-six patients with objective evidence of severe acute pancreatitis received nasogastric feeding within 48 h of admission to our unit.

RESULTS

Etiology was identified as cholelithiasis (18 patients), ethanol (5), and miscellaneous (3). The median Glasgow score was 4 (range 2-7), APACHE II score 10 (4-28), and C-reactive protein concentration 286 mg/L (79-469). Fifteen patients had pancreatic and/or peripancreatic necrosis. Eleven patients developed severe organ failure, necessitating ventilatory support. Six developed multiple organ system failure, requiring inotropic support and/or renal dialysis. There were four deaths (15.3%). Nine patients underwent early, and nine late, ERCP, respectively; six necrosectomy (5 proven infected necrosis, 1 continued deterioration despite maximal support) and 4 patients internal drainage of a pseudocyst. The feed was well-tolerated in 22 patients. In 3 patients gastric stasis proved troublesome. There was no evidence of clinical or biochemical deterioration on commencing nasogastric feeding.

CONCLUSION

It would appear that early NG feeding is usually possible in severe acute pancreatitis. In most patients it appears safe, well-tolerated, and worthy of further study.

Dis-assembly lines: the proteasome and related ATPase-assisted proteases

Self-compartmentalizing proteases, such as the proteasome and several prokaryotic energy-dependent proteases, are designed to act in the crowded environment of the cell. Proteins destined for degradation are recognized and unfolded by regulatory subcomplexes that invariably contain ATPase modules, before being translocated into another subcomplex, the proteolytic core, for degradation. The sequential actions effected on substrates are reflected in the linear arrangement of these subcomplexes; thus, the holocomplexes are organized as molecular disassembly and degradation lines.

Assembly of the herpes simplex virus procapsid from purified components and identification of small complexes containing the major capsid and scaffolding proteins

An in vitro system is described for the assembly of herpes simplex virus type 1 (HSV-1) procapsids beginning with three purified components, the major capsid protein (VP5), the triplexes (VP19C plus VP23), and a hybrid scaffolding protein. Each component was purified from insect cells expressing the relevant protein(s) from an appropriate recombinant baculovirus vector. Procapsids formed when the three purified components were mixed and incubated for 1 h at 37 degrees C. Procapsids assembled in this way were found to be similar in morphology and in protein composition to procapsids formed in vitro from cell extracts containing HSV-1 proteins. When scaffolding and triplex proteins were present in excess in the purified system, greater than 80% of the major capsid protein was incorporated into procapsids. Sucrose density gradient ultracentrifugation studies were carried out to examine the oligomeric state of the purified assembly components. These analyses showed that (i) VP5 migrated as a monomer at all of the protein concentrations tested (0.1 to 1 mg/ml), (ii) VP19C and VP23 migrated together as a complex with the same heterotrimeric composition (VP19C1-VP232) as virus triplexes, and (iii) the scaffolding protein migrated as a heterogeneous mixture of oligomers (in the range of monomers to approximately 30-mers) whose composition was strongly influenced by protein concentration. Similar sucrose gradient analyses performed with mixtures of VP5 and the scaffolding protein demonstrated the presence of complexes of the two having molecular weights in the range of 200,000 to 600,000. The complexes were interpreted to contain one or two VP5 molecules and up to six scaffolding protein molecules. The results suggest that procapsid assembly may proceed by addition of the latter complexes to regions of growing procapsid shell. They indicate further that procapsids can be formed in vitro from virus-encoded proteins only without any requirement for cell proteins.

Named nursing: in whose best interest?

This paper explores certain influences and issues surrounding the implementation and application of the named nurse concept. The author critically examines the proposals that primary nursing increases job satisfaction, cost effectiveness and quality of care, and suggests that as primary nursing appears to be the template for named nursing, these are factors which may have influenced the former British government's decision to implement the concept of named nursing. Owing to problems regarding the reliability and validity of much of the research, the author draws the conclusion that the direct extrapolation from one concept (such as primary nursing) to another (such as named nursing) is perhaps open to question. The author also analyses other issues related to the implementation and use of the named nurse concept including advocacy and accountability, and proposes that the introduction of individualized care, and in particular named nursing, perhaps serves the drive towards the professionalization of nursing first, and the patient second, and if so questions whether there is a need to reconsider the aim of nursing.