Validation of the brain injury associated visual impairment - impact questionnaire (BIVI-IQ)

PURPOSE

The Brain Injury associated Visual Impairment - Impact Questionnaire (BIVI-IQ) was developed to assess the impact of post-stroke visual impairment. The development of the questionnaire used robust methods involving stroke survivors and clinicians. The aim of this study was to assess the validity of the BIVI-IQ in a stroke population.

METHODS

Stroke survivors with visual impairment were recruited from stroke units, outpatient clinics and non-healthcare settings. Participants were asked to complete questionnaire sets on three separate occasions; the BIVI-IQ at each visit with additional questionnaires at baseline and visit 2. Vision assessment and anchor questions from participants and clinicians were collected. The analysis included assessment of missing data, acceptability, Rasch model analysis, test-retest reliability, construct validity (NEI VFQ-25, EQ-5D-5L) and responsiveness to change.

RESULTS

316 stroke survivors completed at least one questionnaire of the 326 recruited. Mean age was 67 years and 64% were male. Adequate fit statistics to the Rasch model were reached (χ2 = 73.12, p = 0.02) with two items removed and thresholds of two adjusted, indicating validity and unidimensionality. Excellent test-retest reliability was demonstrated (ICC = 0.905) with a 3-month interval. Construct validity was demonstrated with a strong significant correlation to the NEI VFQ-25 (r = 0.837, p < 0.01). The BIVI-IQ also demonstrated responsiveness to change with significant differences identified between groups based on participant and clinician anchor questions (X2 = 23.29, p < 0.001; X2 = 24.56, p < 0.001).

CONCLUSION

The BIVI-IQ has been shown to be valid and practical for 'everyday' use by clinicians and researchers to monitor vision-related quality of life in stroke survivors with visual impairment.

Local colonisations and extinctions of European birds are poorly explained by changes in climate suitability

Climate change has been associated with both latitudinal and elevational shifts in species' ranges. The extent, however, to which climate change has driven recent range shifts alongside other putative drivers remains uncertain. Here, we use the changing distributions of 378 European breeding bird species over 30 years to explore the putative drivers of recent range dynamics, considering the effects of climate, land cover, other environmental variables, and species' traits on the probability of local colonisation and extinction. On average, species shifted their ranges by 2.4 km/year. These shifts, however, were significantly different from expectations due to changing climate and land cover. We found that local colonisation and extinction events were influenced primarily by initial climate conditions and by species' range traits. By contrast, changes in climate suitability over the period were less important. This highlights the limitations of using only climate and land cover when projecting future changes in species' ranges and emphasises the need for integrative, multi-predictor approaches for more robust forecasting.

Drivers of the changing abundance of European birds at two spatial scales

Detecting biodiversity change and identifying its causes is challenging because biodiversity is multifaceted and temporal data often contain bias. Here, we model temporal change in species' abundance and biomass by using extensive data describing the population sizes and trends of native breeding birds in the United Kingdom (UK) and the European Union (EU). In addition, we explore how species' population trends vary with species' traits. We demonstrate significant change in the bird assemblages of the UK and EU, with substantial reductions in overall bird abundance and losses concentrated in a relatively small number of abundant and smaller sized species. By contrast, rarer and larger birds had generally fared better. Simultaneously, overall avian biomass had increased very slightly in the UK and was stable in the EU, indicating a change in community structure. Abundance trends across species were positively correlated with species' body mass and with trends in climate suitability, and varied with species' abundance, migration strategy and niche associations linked to diet. Our work highlights how changes in biodiversity cannot be captured easily by a single number; care is required when measuring and interpreting biodiversity change given that different metrics can provide very different insights. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.

Steady-state sound propagation through hot exhaust jets in cooler cross-flow: A computational study

An analysis has been carried out to investigate the sound radiation through a heated jet in cooler cross-flow, which is representative of many industrial exhaust systems, using a hybrid steady-state computational fluid dynamics and computational acoustic model. The mean flow and temperature fields are modelled using steady-state computational fluid dynamics, with the turbulence modelled using Reynolds Averaged Navier-Stokes equations. The corresponding mean flow and temperature fields are used in the computational sound propagation model using linearised acoustic wave equation with mean flow based on a scalar flow potential. The results obtained from the computational simulations show that the flow significantly changes the sound propagation path and that the sound levels downstream of the duct outlet are higher than expected from using an acoustic monopole radiation pattern. The dominant mechanism affecting the propagation of sound is the refraction arising from the plume's temperature and velocity gradients. The sound propagation is highly dependent on the proximity from the duct outlet, normalised wavenumber, temperature and the jet to cross-flow mean velocity ratio. This computational study builds upon previous experimental work to analyse the fluid-acoustic interaction for heated jets in cooler cross-flow to understand the complex radiation pattern that leads to higher-than-expected sound levels downstream of the duct outlet.

Trainee Knowledge and Perceptions of Less Than Full Time Training

Background Less than full-time (LTFT) training in Ireland is still unusual. Our aim was to identify perceived barriers to LTFT training amongst paediatric trainees and make recommendations to improve knowledge, uptake, and experience of LTFT training. Methods An email questionnaire was disseminated to RCPI paediatric trainees to assess current awareness of and perceptions of barriers to LTFT training. Results 218 questionnaires were distributed, 59 (29%) responded of whom 50 (85%) were female. 17 planned to apply for LTFT training. Seven had no knowledge of LTFT training. The perceived barriers with the highest rankings (% respondents deeming highest possible relevance) were: LTFT post availability (49%), potential impact on career progression (51%), and availability of only 0.5 whole time equivalency (WTE) - i.e. 19.5 hours/week (54%). Trainees noted lack of flexibility, including availability of the scheme only from July to July, restriction to maximum 2 years. Trainees felt applications would be rejected if they were not a parent. Some reported perceptions from teams that LTFT trainees are less committed and that trainees can find it difficult to integrate. Discussion Training options including >0.5WTE posts should be made available to all trainees, and a cultural shift within training bodies and with trainers should be encouraged to recognise LTFT training as an acceptable pathway for all trainees.

Identifying features of quality in rural placements for health students: scoping review

OBJECTIVES

To explore and synthesise the evidence relating to features of quality in rural health student placements.

DESIGN

Scoping review.

DATA SOURCES

MEDLINE, CINAHL, Embase, ProQuest, Informit, Scopus, ERIC and several grey literature data sources (1 January 2005 to 13 October 2020).

STUDY SELECTION

The review included peer-reviewed and grey literature from Organisation for Economic Co-operation and Development listed countries that focused on quality of health student placements in regional, rural and remote areas.

DATA EXTRACTION

Data were extracted regarding the methodological and design characteristics of each data source, and the features suggested to contribute to student placement quality under five categories based on a work-integrated learning framework.

RESULTS

Of 2866 resulting papers, 101 were included for data charting and content analysis. The literature was dominated by medicine and nursing student placement research. No literature explicitly defined quality in rural health student placements, although proxy indicators for quality such as satisfaction, positive experiences, overall effectiveness and perceived value were identified. Content analysis resulted in four overarching domains pertaining to features of rural health student placement quality: (1) learning and teaching in a rural context, (2) rural student placement characteristics, (3) key relationships and (4) required infrastructure.

CONCLUSION

The findings suggest that quality in rural health student placements hinges on contextually specific features. Further research is required to explore these findings and ways in which these features can be measured during rural health student placements.

Enhancing paediatric palliative care: A rapid review to inform continued development of care for children with life-limiting conditions

AIM

Following the establishment of paediatric palliative care services over recent decades, this study sought to identify information to inform future policy and practice.

METHODS

A rapid review using thematic synthesis was conducted to synthesise existing information about improving paediatric palliative care. Information was extracted in relation to key areas for investment and change: quality, access, advance care planning, skills, research, collaboration and community awareness.

RESULTS

A total of 2228 literature sources were screened, with 369 included. Synthesised information identified clear ways to improve quality of care, access to care, advance care planning, and research and data collection. The synthesis identified knowledge gaps in understanding how to improve skills in paediatric palliative care, collaboration across Australian jurisdictions and community awareness.

CONCLUSIONS

The findings of this review bring together information from a vast range of sources to provide action-oriented information to target investment and change in paediatric palliative care over the coming decades.

Sound propagation through elevated, heated jets in cooler cross-flow: An experimental study

Sound propagation through hot exhaust plumes with cooler cross-winds is present in many real world systems. One particular example is the sound propagation from exhaust stacks attached to open cycle gas turbine power stations. The research presented in this paper investigates the sound propagation from a reduced-scale exhaust stack, with a cross-flow from experiments conducted in a wind tunnel. Experimental measurements of the flow and temperature fields provide insight into the complex sound radiation characteristics. Results from the acoustic measurements show the change in the sound directivity arising from the inclusion of the hot exhaust plume, leading to non-axisymmetric sound directivity and a concentration of sound downwind of the exhaust stack outlet. In certain cross-flow conditions, the hot exhaust plume can increase the sound observed downwind by up to 11 dB when compared to the scenario of sound propagation from an exhaust stack in the absence of a heated jet or cross-flow. This paper describes the acoustic directivity at various radial distances from the exhaust stack, acoustic frequencies, jet temperatures, and cross-flow free-stream velocity. The results from this paper emphasise the importance of taking into consideration the hot exhaust plume with cooler cross-flow when estimating sound levels downwind of the stack.

Observed psychopathology in offspring of parents with major depressive disorder, bipolar disorder and schizophrenia

BACKGROUND

Children of parents with mood and psychotic disorders are at elevated risk for a range of behavioral and emotional problems. However, as the usual reporter of psychopathology in children is the parent, reports of early problems in children of parents with mood and psychotic disorders may be biased by the parents' own experience of mental illness and their mental state.

METHODS

Independent observers rated psychopathology using the Test Observation Form in 378 children and youth between the ages of 4 and 24 (mean = 11.01, s.d. = 4.40) who had a parent with major depressive disorder, bipolar disorder, schizophrenia, or no history of mood and psychotic disorders.

RESULTS

Observed attentional problems were elevated in offspring of parents with major depressive disorder, bipolar disorder and schizophrenia (effect sizes ranging between 0.31 and 0.56). Oppositional behavior and language/thought problems showed variable degrees of elevation (effect sizes 0.17 to 0.57) across the three high-risk groups, with the greatest difficulties observed in offspring of parents with bipolar disorder. Observed anxiety was increased in offspring of parents with major depressive disorder and bipolar disorder (effect sizes 0.19 and 0.25 respectively) but not in offspring of parents with schizophrenia.

CONCLUSIONS

Our results suggest that externalizing problems and cognitive and language difficulties may represent a general manifestation of familial risk for mood and psychotic disorders, while anxiety may be a specific marker of liability for mood disorders. Observer assessment may improve early identification of risk and selection of youth who may benefit from targeted prevention.

A global assessment of the drivers of threatened terrestrial species richness

High numbers of threatened species might be expected to occur where overall species richness is also high; however, this explains only a proportion of the global variation in threatened species richness. Understanding why many areas have more or fewer threatened species than would be expected given their species richness, and whether that is consistent across taxa, is essential for identifying global conservation priorities. Here, we show that, after controlling for species richness, environmental factors, such as temperature and insularity, are typically more important than human impacts for explaining spatial variation in global threatened species richness. Human impacts, nevertheless, have an important role, with relationships varying between vertebrate groups and zoogeographic regions. Understanding this variation provides a framework for establishing global conservation priorities, identifying those regions where species are inherently more vulnerable to the effects of threatening human processes, and forecasting how threatened species might be distributed in a changing world.

African Enculturation and Performance on the African Neuropsychological Battery

Objective

To test a core assumption of the African Neuropsychology Battery (ANB) that greater African enculturation is associated with better performance.

Method

Subjects were 27 African immigrants to the U.S. [mean age = 39 (SD = 11.5), mean education = 16.3 years (SD = 2.9)], 32 African-Americans [mean age = 34.0 (SD = 11.2), mean education = 16.2 (SD = 2.5)], and 21 U.S. Caucasians [mean age = 45.7 (SD = 13.8), mean education = 17.2 (SD = 2.3)]. All subjects completed a questionnaire on familiarity with elements of African culture. The ANB was administered one-on-one, by trained technicians, in English, in a single session. ANB tests measured visuospatial perception, naming, memory, and abstract reasoning utilizing content drawn from sub-Saharan African cultures.

Results

Groups differed significantly in age (p < .05), but not education or gender, and age was used as a covariate in subsequent group comparisons. African immigrants showed highest African enculturation, followed by African Americans, and Caucasians [F(2, 74) = 36.16, p < .000], with all groups differing significantly from one another in post-hoc comparisons (p < .02). African enculturation correlated significantly only with ability to identify pictures of African fruits (Pearson r = .58, p < .001) and objects (r = .25, p < .03). Analysis of Covariance followed by Bonferroni post-hoc comparisons confirmed that African immigrants were superior to Caucasians (p < .001) and African-Americans (p < .001) in identifying fruits, with the latter two groups not differing significantly from one another. African immigrants were superior to Caucasians in object identification (p < .05), but did not differ significantly from African-Americans.

Conclusions

African enculturation influences performance on some ANB tests and results support the potential of the ANB to assess performance in a less culturally-biased manner in African immigrants.

Flight range, fuel load and the impact of climate change on the journeys of migrant birds

Climate change is predicted to increase migration distances for many migratory species, but the physiological and temporal implications of longer migratory journeys have not been explored. Here, we combine information about species' flight range potential and migratory refuelling requirements to simulate the number of stopovers required and the duration of current migratory journeys for 77 bird species breeding in Europe. Using tracking data, we show that our estimates accord with recorded journey times and stopovers for most species. We then combine projections of altered migratory distances under climate change with models of avian flight to predict future migratory journeys. We find that 37% of migratory journeys undertaken by long-distance migrants will necessitate an additional stopover in future. These greater distances and the increased number of stops will substantially increase overall journey durations of many long-distance migratory species, a factor not currently considered in climate impact studies.

A pilot randomized controlled trial comparing effectiveness of prism glasses, visual search training and standard care in hemianopia

OBJECTIVE

Pilot trial to compare prism therapy and visual search training, for homonymous hemianopia, to standard care (information only).

METHODS

Prospective, multicentre, parallel, single-blind, three-arm RCT across fifteen UK acute stroke units.

PARTICIPANTS

Stroke survivors with homonymous hemianopia.

INTERVENTIONS

Arm a (Fresnel prisms) for minimum 2 hours, 5 days per week over 6 weeks. Arm b (visual search training) for minimum 30 minutes, 5 days per week over 6 weeks. Arm c (standard care-information only).

INCLUSION CRITERIA

Adult stroke survivors (>18 years), stable hemianopia, visual acuity better than 0.5 logMAR, refractive error within ±5 dioptres, ability to read/understand English and provide consent.

OUTCOMES

Primary outcomes were change in visual field area from baseline to 26 weeks and calculation of sample size for a definitive trial. Secondary measures included Rivermead Mobility Index, Visual Function Questionnaire 25/10, Nottingham Extended Activities of Daily Living, Euro Qual, Short Form-12 questionnaires and Radner reading ability. Measures were post-randomization at baseline and 6, 12 and 26 weeks.

RANDOMIZATION

Randomization block lists stratified by site and partial/complete hemianopia.

BLINDING

Allocations disclosed to patients. Primary outcome assessor blind to treatment allocation.

RESULTS

Eighty-seven patients were recruited: 27-Fresnel prisms, 30-visual search training and 30-standard care; 69% male; mean age 69 years (SD 12). At 26 weeks, full results for 24, 24 and 22 patients, respectively, were compared to baseline. Sample size calculation for a definitive trial determined as 269 participants per arm for a 200 degree² visual field area change at 90% power. Non-significant relative change in area of visual field was 5%, 8% and 3.5%, respectively, for the three groups. Visual Function Questionnaire responses improved significantly from baseline to 26 weeks with visual search training (60 [SD 19] to 68.4 [SD 20]) compared to Fresnel prisms (68.5 [SD 16.4] to 68.2 [18.4]: 7% difference) and standard care (63.7 [SD 19.4] to 59.8 [SD 22.7]: 10% difference), P=.05. Related adverse events were common with Fresnel prisms (69.2%; typically headaches).

CONCLUSIONS

No significant change occurred for area of visual field area across arms over follow-up. Visual search training had significant improvement in vision-related quality of life. Prism therapy produced adverse events in 69%. Visual search training results warrant further investigation.

A randomised controlled trial to compare the clinical and cost-effectiveness of prism glasses, visual search training and standard care in patients with hemianopia following stroke: a protocol

INTRODUCTION

Homonymous hemianopia is a common and disabling visual problem after stroke. Currently, prism glasses and visual scanning training are proposed to improve it. The aim of this trial is to determine the effectiveness of these interventions compared to standard care.

METHODS AND ANALYSIS

The trial will be a multicentre three arm individually randomised controlled trial with independent assessment at 6 week, 12 week and 26 week post-randomisation. Recruitment will occur in hospital, outpatient and primary care settings in UK hospital trusts. A total of 105 patients with homonymous hemianopia and without ocular motility impairment, visual inattention or pre-existent visual field impairment will be randomised to one of three balanced groups. Randomisation lists will be stratified by site and hemianopia level (partial or complete) and created using simple block randomisation by an independent statistician. Allocations will be disclosed to patients by the treating clinician, maintaining blinding for outcome assessment. The primary outcome will be change in visual field assessment from baseline to 26 weeks. Secondary measures will include the Rivermead Mobility Index, Visual Function Questionnaire 25/10, Nottingham Extended Activities of Daily Living, Euro Qual-5D and Short Form-12 questionnaires. Analysis will be by intention to treat.

ETHICS AND DISSEMINATION

This study has been developed and supported by the UK Stroke Research Network Clinical Studies Group working with service users. Multicentre ethical approval was obtained through the North West 6 Research ethics committee (Reference 10/H1003/119). The trial is funded by the UK Stroke Association. Trial Registration: Current Controlled Trials ISRCTN05956042. Dissemination will consider usual scholarly options of conference presentation and journal publication in addition to patient and public dissemination with lay summaries and articles.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN05956042.

Conditions for enhancing the encoding of an elementary motor memory by rTMS

OBJECTIVE

Motor learning results in changes of movement representation in primary motor cortex (M1) a process involving long-term potentiation (LTP). Pairing motor training with repetitive transcranial magnetic stimulation (rTMS) of M1 enhances the formation of a motor memory. Here we determined the effect of pairing M1 stimulation and the execution of training movements at different times and frequencies on the formation of a motor memory.

METHODS

Formation of a motor memory was defined as increases in motor evoked potentials (MEP) of the training agonist (extensor carpi ulnaris muscle, ECU) and increases in peak acceleration of the trained movements that last more than 60min. Training consisted of auditory-paced ballistic wrist extension movements (30min, 0.5Hz) paired with 0.1, 0.25 or 0.5Hz subthreshold rTMS. The rTMS pulse was applied at either the onset, 100ms prior to or 300ms after the onset of training movement related increases in electromyographic (EMG) activity of ECU. This was compared to a Sham condition.

RESULTS

Only 0.1Hz rTMS applied at the onset of the training related increase in ECU-EMG activity resulted in increases in MEP amplitudes and peak acceleration when compared to the Sham.

CONCLUSIONS

The formation of motor memory is enhanced above the naïve level by co-administration of low frequency rTMS at the time of execution of training movements.

SIGNIFICANCE

These results indicate the importance of time and frequency of rTMS in these settings and should be considered in the design of rehabilitation treatment strategies using rTMS.

Text messaging to support off-campus clinical nursing facilitators: a descriptive survey

BACKGROUND

Managing large student cohorts can be a challenge for university academics, coordinating these units. Bachelor of Nursing programmes have the added challenge of managing multiple groups of students and clinical facilitators whilst completing clinical placement. Clear, time efficient and effective communication between coordinating academics and clinical facilitators is needed to ensure consistency between student and teaching groups and prompt management of emerging issues.

METHODS

This study used a descriptive survey to explore the use of text messaging via a mobile phone, sent from coordinating academics to off-campus clinical facilitators, as an approach to providing direction and support.

RESULTS

The response rate was 47.8% (n=22). Correlations were found between the approachability of the coordinating academic and clinical facilitator perception that, a) the coordinating academic understood issues on clinical placement (r=0.785, p<0.001), and b) being part of the teaching team (r=0.768, p<0.001). Analysis of responses to qualitative questions revealed three themes: connection, approachability and collaboration.

CONCLUSIONS

This study demonstrates that use of regular text messages improves communication between coordinating academics and clinical facilitators. Findings suggest improved connection, approachability and collaboration between the coordinating academic and clinical facilitation staff.

Electron-phonon coupling on the surface of the topological insulator Bi2Se3 determined from surface-phonon dispersion measurements

In this Letter, we report measurements of the coupling between Dirac fermion quasiparticles (DFQs) and phonons on the (001) surface of the strong topological insulator Bi2Se3. While most contemporary investigations of this coupling have involved examining the temperature dependence of the DFQ self-energy via angle-resolved photoemission spectroscopy measurements, we employ inelastic helium-atom scattering to explore, for the first time, this coupling from the phonon perspective. Using a Hilbert transform, we are able to obtain the imaginary part of the phonon self-energy associated with a dispersive surface-phonon branch identified in our previous work [Phys. Rev. Lett. 107, 186102 (2011)] as having strong interactions with the DFQs. From this imaginary part of the self-energy we obtain a branch-specific electron-phonon coupling constant of 0.43, which is stronger than the values reported from the angle-resolved photoemission spectroscopy measurements.

An experimental study on costal osteochondral graft

OBJECTIVE

To investigate usefulness of osteochondral grafting from the costo-osteochondral junction as a repair technique for articular cartilage defects histologic and biochemical analysis of grafted cartilage in rabbit knees was evaluated up to 48 weeks after transplantation.

METHODS

Twenty New Zealand White rabbits were used. A costal osteochondral plug was harvested from a middle rib. After trimming, it was transplanted into a cylindrical osteochondral 2.5 mm diameter and 5 mm deep defect created in the knee. The animals were sacrificed at 6, 12, 24, and 48 weeks after transplantation. Defect sites were inspected macroscopically, and then by light microscopy. Samples were evaluated for cell viability using a fluorescent in situ double-staining protocol with confocal laser microscopic analysis. Samples were also processed to assess type I & II collagen and aggrecan mRNA expression using reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Histologically, bone union was achieved in all plugs. Confocal microscopic analysis revealed chondrocyte viability in the 48-week grafts; the distribution of chondrocytes was similar to surrounding articular cartilage. The expression of type II collagen and aggrecan mRNA in the grafted cartilage was consistent with normal articular cartilage and normal costal cartilage. These results were observed over 6-48 weeks.

CONCLUSIONS

Our study revealed that chondrocytes in the grafted cartilage were viable at least up to 48 weeks and that mRNA expression of type II collagen and aggrecan was also similar to that of normal articular cartilage. These results suggest that costal osteochondral grafting can be a useful alternative in the treatment of osteochondral defects.

Interaction of phonons and dirac fermions on the surface of Bi2Se3: a strong Kohn anomaly

We report the first measurements of phonon dispersion curves on the (001) surface of the strong three-dimensional topological insulator Bi2Se3. The surface phonon measurements were carried out with the aid of coherent helium beam surface scattering techniques. The results reveal a prominent signature of the exotic metallic Dirac fermion quasiparticles, including a strong Kohn anomaly. The signature is manifest in a low energy isotropic convex dispersive surface phonon branch with a frequency maximum of 1.8 THz and having a V-shaped minimum at approximately 2kF that defines the Kohn anomaly. Theoretical analysis attributes this dispersive profile to the renormalization of the surface phonon excitations by the surface Dirac fermions. The contribution of the Dirac fermions to this renormalization is derived in terms of a Coulomb-type perturbation model.

Open Air Laboratories (OPAL): a community-driven research programme

OPAL is an English national programme that takes scientists into the community to investigate environmental issues. Biological monitoring plays a pivotal role covering topics of: i) soil and earthworms; ii) air, lichens and tar spot on sycamore; iii) water and aquatic invertebrates; iv) biodiversity and hedgerows; v) climate, clouds and thermal comfort. Each survey has been developed by an inter-disciplinary team and tested by voluntary, statutory and community sectors. Data are submitted via the web and instantly mapped. Preliminary results are presented, together with a discussion on data quality and uncertainty. Communities also investigate local pollution issues, ranging from nitrogen deposition on heathlands to traffic emissions on roadside vegetation. Over 200,000 people have participated so far, including over 1000 schools and 1000 voluntary groups. Benefits include a substantial, growing database on biodiversity and habitat condition, much from previously unsampled sites particularly in urban areas, and a more engaged public.

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

Efficacy, safety and lack of immunogenicity of insulin aspart compared with regular human insulin for women with gestational diabetes mellitus

AIM

The efficacy and safety of insulin aspart (IAsp), a rapid-acting human insulin analogue, were compared with regular human insulin (HI) as the bolus component of basal-bolus therapy for subjects with gestational diabetes mellitus (GDM).

METHODS

In a randomized, parallel-group, open-labelled trial, 27 women with GDM (age 30.7 +/- 6.3 years, HbA(1c) < 7%) were randomized to receive IAsp (5 min before meal) or HI (30 min before meal). The trial period extended from diagnosis of GDM (18-28 weeks) to 6 weeks postpartum.

RESULTS

Both treatment groups maintained good overall glycaemic control during the study (beginning and end of study HbA(1c)< or = 6%). During the meal test, mean glucose at week 6 (IAsp 4.2 +/- 0.57 mmol/l, HI 4.8 +/- 0.86 mmol/l) was slightly lower than at week 0 (IAsp 4.9 +/- 0.59 mmol/l, HI 5.1 +/- 0.36 mmol/l). However, change from baseline values for average glucose (IAsp -1.09 +/- 0.54 mmol/l, HI -0.54 +/- 0.74 mmol/l; P = 0.003) and C-peptide (IAsp -0.50 +/- 0.67 nmol/l, HI -0.30 +/- 0.70 nmol/l; P = 0.027) were significantly lower after IAsp treatment than HI treatment. No major hypoglycaemic events were reported during the study. Cross-reacting insulin antibody binding increased slightly from baseline in both treatments groups (end of study: IAsp 2.1 +/- 5.4%, HI 6.4 +/- 13.9%), whereas antibodies specific to IAsp or HI remained relatively low (< 1% binding).

CONCLUSION

IAsp was more effective than HI in decreasing postprandial glucose concentrations. Duration of IAsp injection 5 min before a meal rather than 30 min prior to meals offers a more convenient therapy for subjects with GDM. Overall safety and effectiveness of IAsp were comparable to HI in pregnant women with GDM.

Comparison of the antibody in lymphocyte supernatant (ALS) and ELISPOT assays for detection of mucosal immune responses to antigens of enterotoxigenic Escherichia coli in challenged and vaccinated volunteers

In the present study we compared the ELISPOT and antibody in lymphocyte supernatants (ALS) assays as surrogate measures of mucosal immunity. In separate studies, 20 inpatient volunteers received oral doses of 6 x 10(8) or 4 x 10(9)cfu of ETEC strain E24377A (LT+, ST+, CS1+, CS3+) and 20 subjects received 1 (n = 9) or 2 (n = 11) oral doses of the attenuated ETEC vaccine, PTL-003 expressing CFA/II (CS1+ and CS3+) (2 x 10(9)cfu/dose). Peripheral blood mononuclear cells (PBMCs) from all subjects were assayed for anti-colonization factor or toxin-specific IgA antibody responses using the ALS and ELISPOT procedures. ALS responses were measured using a standard ELISA, as well as by time-resolved fluorescence (TRF). Following challenge with E24377A, significant anti-CS3, CS1 and LT ALS responses were detected in the lymphocyte supernatants of 75-95% of the subjects. A similar proportion (75%) of subjects mounted an ALS response to CFA/II antigen after vaccination with the PTL-003 vaccine. Inter-assay comparisons between ALS and ELISPOT methods also revealed a high degree of correlation in both immunization groups. ALS sensitivity versus the ELISPOT assay for LT, CS3 and CS1-specific responses following challenge were 95%, 94% and 78%, respectively and 83% for the ALS response to CFA/II antigen after vaccination with PTL-003. Correlation coefficients for the LT and CS3 antigens were 0.94 (p<0.001) and 0.82 (p<0.001), respectively after challenge and 0.78 (p<0.001) after vaccination. The association between ALS and ELISPOT for the CS1 antigen was however, significant only when ALS supernatants were tested by TRF (r = 0.91, p<0.001). These results demonstrate the value and flexibility of the ALS assay as an alternative to ELISPOT for the measurement of mucosal immune responses to ETEC antigens, particularly when the complexities of ELISPOT may make it impractical to perform.

The anatomy of tibial eminence fractures: arthroscopic observations following failed closed reduction

BACKGROUND

Failed manipulative reduction of avulsion fractures of the tibial insertion of the anterior cruciate ligament has been attributed to interposition of soft tissues, particularly the anterior horn of the medial meniscus. The objectives of the present report were (1) to show that the failure to reduce Meyers and McKeever type-III tibial eminence fractures was not due to interposition of soft tissues and (2) to discuss the relevance of the finding that the anterior third of the lateral meniscus was attached to the avulsed anterior cruciate ligament insertion site in all patients studied.

METHODS

Twelve patients who had had a failed manipulative reduction of a type-III tibial eminence fracture underwent arthroscopic reduction and fixation of the avulsed fragment.

RESULTS

A number of consistent findings were noted. The avulsed intercondylar eminence was displaced superiorly into the intercondylar notch. Attached to this fragment was not only the anterior cruciate ligament, but also, in all cases, the anterior horn of the lateral meniscus. The anterior third of the lateral meniscus had been torn from its tibial attachment and displaced together with the osseous fragment into the intercondylar notch. No interposition of bone or soft tissue was observed. Reduction of the osseous fragment was facilitated by traction on, or sutures passed around, the anterior horn of the lateral meniscus. Standard fixation methods were utilized.

CONCLUSIONS

The concept that avulsion fractures of the tibial insertion of the anterior cruciate ligament cannot be reduced by manipulation because of soft-tissue interposition was not supported by the findings of the present study. The attachment of the anterior horn of the lateral meniscus to the avulsed tibial insertion of the anterior cruciate ligament may not be an irrelevant incidental finding. The observation that the displaced osseous fragment was attached simultaneously to the anterior cruciate ligament and to the anterior horn of the lateral meniscus, both pulling in different directions, may explain why type-III tibial eminence fractures are irreducible by manipulation.

Mycobacterium paratuberculosis heat shock protein 70 as a tool in control of paratuberculosis

Paratuberculosis in cattle is a chronic intestinal disease in which a distinctive cellular reactivity of a Th1-type preceeds the phase in which antibody titers are easily detectable and the animal becomes clinically ill. During infection with Mycobacterium avium ssp. paratuberculosis (M.a.p), a decrease in CD4 T-helper cells has been observed in the clinical phase. Our ultimate aim is to elicit a cytotoxic reaction against infected macrophages, using recombinant Hsp70 (rHsp70) of M.a.p. as a tool to shuttle antigen into the MHC class I antigen presentation pathway. To investigate the mechanism of rHsp70 as a carrier for antigen into the cell, we studied the interaction between APC and Fitc-labelled rHsp70, using FACS analysis and confocal microscopy. Interaction of rHsp70 with the cell surface of bovine APC, presumably via a receptor, was shown on monocytes, monocyte derived macrophages and dendritic cell (DC). The interaction is detectable on the complete population of freshly derived monocytes, although peak intensity of fluorescence is lower on these cells than on macrophages and DCs. DCs show interaction on a high percentage of the cells, with high intensity, while in the case of macrophages only a subpopulation interacts with rHsp70. Efficient uptake of rHsp70 as compared to OVA is shown. Preincubation of DC with unlabelled rHsp70 leads to a decreased interaction with rHsp70-FITC. DC interacting with rHsp70 in addition showed high expression of MHC I, MHC II, Myd-1 (CD172a) and CD40. Further research will focus on loading of the rHsp70 with M.a.p. antigen for presentation in MHC class I.