6 research outputs found
Phonological Short-Term Memory and New Word Learning: Evidence from Paired-Associate and Hebb Repetition Paradigms
This thesis investigated the role of phonological short-term memory (PSTM) in
the long-term learning of new phonological word-forms.. Previous studies using the
paired-associate paradigm have suggested that the learning of unfamiliar material is
mediated by PSTM (e.g. Papagno & Vallar, 1992). The first'aim was. to replicate a!1d
extend this previous work. The second aim was to determine whether the Hebb
repetition paradigm could provide an alternative method with which to investigate the
role of PSTM in new word-form learning. Seven experiments w~re conducted to
explore these aims.
Experiment 1 obtained phonological similarity effects for words and nonwords in
an immediate serial recall task, confirming that. the chosen manipulation of
phonological similarity was adequate. Experiments 2 and' 3 . adopted the
paired-associate task and replicated Papagno and Vallar' (1992), thus extending their
results to English participants and materials. Phonological similarity was shown to
selectively disrupt the learning of nonword pairs. In contrast, some evidence was found
to suggest that phonological similarity fails to affect the learning' of word pairs.
However, Experiment 3 showed that the detrimental effect of phonological similarity
was restricted to an intermediate phase of learning. These findings suggest that PSTM
mediates the learning of unfamiliar material, although the role of PSTM may change
during the course of learning; Experiments 4 and 6 adopted the Hebb repetition task
and generated patterns of results consistent with Papagno and Vallar (1992) and
Experiments 2 and 3. Phonological similarity disrupted the learning of nonword
s~quences, but not the learning of word sequences. These findings suggest that PSTM
mediates sequence learning for unfamiliar material, thereby providing initia~ evidence
that the Hebb repetition paradigm may be a possible analogue of new word-form
learning. The role qf PSTM in nonword sequence learning could not be reliably
assessed in Experiments 5 and 7 due to the absence of reliable Hebb Effects. Analyses
of between-trial learning and forgetting rates using a Markov model revealed that
phonological similarity had a negative impact on forgetting rates for nonwords in both
paired-assoCiate and. Hebb repetItion paradigms, suggesting that phonological
representations of nonwords are particularly fragile. Finally, it is proposed that the
paired-associate paradigm represents a closer analogue of new word-form learning than
the Hebb repetition paradigm as it makes use of existing lexical-semantic information
Community pharmacies mood intervention Study (CHEMIST) Feasibility and External Pilot randomised controlled trial protocol
Feasibility study: Objectives:Refine a bespoke enhanced support intervention (ESI) (including self-help materials, intervention manual and training) for implementation by community pharmacy (CP) staff to people with sub-threshold depression and long-term conditions (LTCs) based upon evidence-supported interventions in primary careDevelop and refine study procedures (recruitment strategies and set up, screening, participant recruitment, assessment, suitability of outcome measures and data collection procedures) for testing in the pilot study phaseDesign: A case series/qualitative studySetting: UK community pharmacyPopulation: Adults with long-term health conditions who screen-positive for depression but who do not reach the threshold for DSM IV Moderate Depressive disorderIntervention: Enhanced support intervention (ESI) delivered by an appropriately trained community pharmacy team member involving four to six sessions over four months. ESI is a modified form of an intervention within the collaborative care framework for sub-threshold depression validated in previous studies in UK primary care which appears suitable for implementation in community settings.Sample size: 20-30 participantsOutcomes: Study implementation (recruitment and attrition rates), quality of data collection at baseline and 4 months and ESI adherence (number of contacts, DNA and drop out) as per objectives 1a/bQualitative evaluation: Semi-structured interviews with up to 10 participants and ESI facilitators and focus group(s) (range of pharmacy staff n = 8-10) will be conducted to explore the acceptability of the intervention and feasibility of the study, training and study procedures. External pilot study: Objectives:Quantify the flow of participants (eligibility, recruitment and follow-up rate)Evaluate proposed recruitment, assessment and outcome measure collection methodsExamine the delivery of the enhanced support intervention in a community pharmacy setting (intervention uptake, retention and dose) to inform process evaluationProcess evaluation, using semi-structured interviews with participants across a range of socio-economic settings, and pharmacy staff to explore the acceptability of the ESI within community pharmacy, elements of the intervention that were considered useful (or not) and appropriateness of study proceduresDesign: Pilot randomised controlled trial, including a prospective economic and qualitative evaluationSetting: As abovePopulation: As aboveIntervention: As above with adaptations post feasibility studyComparator: Usual careSample size: 100 participantsOutcomes: Data will be used to estimate recruitment, intervention delivery and study completion rates as per objectives 2a-d. Definitive estimates of the effectiveness of ESI will not be made.Primary outcome: Depression severity (Patient Health Questionnaire 9) at four months.Secondary outcomes: Patient acceptance, uptake and attrition. ICD10 depression status, anxiety (GAD 7), health-related quality of life (SF-12v2) and health-state utility (EQ5D 3L) will be measured at four months.Economic evaluation: The incremental cost per QALY will be calculated from both the NHS and societal perspective.Process evaluation: Using mixed methods, potential mediators/moderators of the intervention, the acceptability (to participants and pharmacy staff), barriers and facilitators to the use of ESI in community pharmacy, and impact on usual practice will be examined. Semi-structured interviews with approximately 30 study participants, 20 pharmacy staff and eight GPs near participating pharmacies will be conducted. Trial registration: ISRCTN: ISRCTN11290592Protocol version number: Version 4.1 (dated 16th January 2018)Study Sponsor Tees Esk and Wear Valleys NHS Foundation Trust
Clinical outcomes and response to treatment of patients receiving topical treatments for pyoderma gangrenosum: a prospective cohort study
Background: pyoderma gangrenosum (PG) is an uncommon dermatosis with a limited evidence base for treatment.
Objective: to estimate the effectiveness of topical therapies in the treatment of PG.
Methods: prospective cohort study of UK secondary care patients with a clinical diagnosis of PG suitable for topical treatment (recruited July 2009 to June 2012). Participants received topical therapy following normal clinical practice (mainly Class I-III topical corticosteroids, tacrolimus 0.03% or 0.1%). Primary outcome: speed of healing at 6 weeks. Secondary outcomes: proportion healed by 6 months; time to healing; global assessment; inflammation; pain; quality-of-life; treatment failure and recurrence.
Results: Sixty-six patients (22 to 85 years) were enrolled. Clobetasol propionate 0.05% was the most commonly prescribed therapy. Overall, 28/66 (43.8%) of ulcers healed by 6 months. Median time-to-healing was 145 days (95% CI: 96 days, ∞). Initial ulcer size was a significant predictor of time-to-healing (hazard ratio 0.94 (0.88;80 1.00); p = 0.043). Four patients (15%) had a recurrence.
Limitations: No randomised comparator
Conclusion: Topical therapy is potentially an effective first-line treatment for PG that avoids possible side effects associated with systemic therapy. It remains unclear whether more severe disease will respond adequately to topical therapy alone
Safety, immunogenicity, and reactogenicity of BNT162b2 and mRNA-1273 COVID-19 vaccines given as fourth-dose boosters following two doses of ChAdOx1 nCoV-19 or BNT162b2 and a third dose of BNT162b2 (COV-BOOST): a multicentre, blinded, phase 2, randomised trial
Background Some high-income countries have deployed fourth doses of COVID-19 vaccines, but the clinical need, effectiveness, timing, and dose of a fourth dose remain uncertain. We aimed to investigate the safety, reactogenicity, and immunogenicity of fourth-dose boosters against COVID-19.Methods The COV-BOOST trial is a multicentre, blinded, phase 2, randomised controlled trial of seven COVID-19 vaccines given as third-dose boosters at 18 sites in the UK. This sub-study enrolled participants who had received BNT162b2 (Pfizer-BioNTech) as their third dose in COV-BOOST and randomly assigned them (1:1) to receive a fourth dose of either BNT162b2 (30 µg in 0·30 mL; full dose) or mRNA-1273 (Moderna; 50 µg in 0·25 mL; half dose) via intramuscular injection into the upper arm. The computer-generated randomisation list was created by the study statisticians with random block sizes of two or four. Participants and all study staff not delivering the vaccines were masked to treatment allocation. The coprimary outcomes were safety and reactogenicity, and immunogenicity (antispike protein IgG titres by ELISA and cellular immune response by ELISpot). We compared immunogenicity at 28 days after the third dose versus 14 days after the fourth dose and at day 0 versus day 14 relative to the fourth dose. Safety and reactogenicity were assessed in the per-protocol population, which comprised all participants who received a fourth-dose booster regardless of their SARS-CoV-2 serostatus. Immunogenicity was primarily analysed in a modified intention-to-treat population comprising seronegative participants who had received a fourth-dose booster and had available endpoint data. This trial is registered with ISRCTN, 73765130, and is ongoing.Findings Between Jan 11 and Jan 25, 2022, 166 participants were screened, randomly assigned, and received either full-dose BNT162b2 (n=83) or half-dose mRNA-1273 (n=83) as a fourth dose. The median age of these participants was 70·1 years (IQR 51·6–77·5) and 86 (52%) of 166 participants were female and 80 (48%) were male. The median interval between the third and fourth doses was 208·5 days (IQR 203·3–214·8). Pain was the most common local solicited adverse event and fatigue was the most common systemic solicited adverse event after BNT162b2 or mRNA-1273 booster doses. None of three serious adverse events reported after a fourth dose with BNT162b2 were related to the study vaccine. In the BNT162b2 group, geometric mean anti-spike protein IgG concentration at day 28 after the third dose was 23 325 ELISA laboratory units (ELU)/mL (95% CI 20 030–27 162), which increased to 37 460 ELU/mL (31 996–43 857) at day 14 after the fourth dose, representing a significant fold change (geometric mean 1·59, 95% CI 1·41–1·78). There was a significant increase in geometric mean anti-spike protein IgG concentration from 28 days after the third dose (25 317 ELU/mL, 95% CI 20 996–30 528) to 14 days after a fourth dose of mRNA-1273 (54 936 ELU/mL, 46 826–64 452), with a geometric mean fold change of 2·19 (1·90–2·52). The fold changes in anti-spike protein IgG titres from before (day 0) to after (day 14) the fourth dose were 12·19 (95% CI 10·37–14·32) and 15·90 (12·92–19·58) in the BNT162b2 and mRNA-1273 groups, respectively. T-cell responses were also boosted after the fourth dose (eg, the fold changes for the wild-type variant from before to after the fourth dose were 7·32 [95% CI 3·24–16·54] in the BNT162b2 group and 6·22 [3·90–9·92] in the mRNA-1273 group).Interpretation Fourth-dose COVID-19 mRNA booster vaccines are well tolerated and boost cellular and humoral immunity. Peak responses after the fourth dose were similar to, and possibly better than, peak responses after the third dose
Safety and immunogenicity of seven COVID-19 vaccines as a third dose (booster) following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK (COV-BOOST): a blinded, multicentre, randomised, controlled, phase 2 trial
Background:
Few data exist on the comparative safety and immunogenicity of different COVID-19 vaccines given as a third (booster) dose. To generate data to optimise selection of booster vaccines, we investigated the reactogenicity and immunogenicity of seven different COVID-19 vaccines as a third dose after two doses of ChAdOx1 nCov-19 (Oxford–AstraZeneca; hereafter referred to as ChAd) or BNT162b2 (Pfizer–BioNtech, hearafter referred to as BNT).
Methods:
COV-BOOST is a multicentre, randomised, controlled, phase 2 trial of third dose booster vaccination against COVID-19. Participants were aged older than 30 years, and were at least 70 days post two doses of ChAd or at least 84 days post two doses of BNT primary COVID-19 immunisation course, with no history of laboratory-confirmed SARS-CoV-2 infection. 18 sites were split into three groups (A, B, and C). Within each site group (A, B, or C), participants were randomly assigned to an experimental vaccine or control. Group A received NVX-CoV2373 (Novavax; hereafter referred to as NVX), a half dose of NVX, ChAd, or quadrivalent meningococcal conjugate vaccine (MenACWY) control (1:1:1:1). Group B received BNT, VLA2001 (Valneva; hereafter referred to as VLA), a half dose of VLA, Ad26.COV2.S (Janssen; hereafter referred to as Ad26) or MenACWY (1:1:1:1:1). Group C received mRNA1273 (Moderna; hereafter referred to as m1273), CVnCov (CureVac; hereafter referred to as CVn), a half dose of BNT, or MenACWY (1:1:1:1). Participants and all investigatory staff were blinded to treatment allocation. Coprimary outcomes were safety and reactogenicity and immunogenicity of anti-spike IgG measured by ELISA. The primary analysis for immunogenicity was on a modified intention-to-treat basis; safety and reactogenicity were assessed in the intention-to-treat population. Secondary outcomes included assessment of viral neutralisation and cellular responses. This trial is registered with ISRCTN, number 73765130.
Findings:
Between June 1 and June 30, 2021, 3498 people were screened. 2878 participants met eligibility criteria and received COVID-19 vaccine or control. The median ages of ChAd/ChAd-primed participants were 53 years (IQR 44–61) in the younger age group and 76 years (73–78) in the older age group. In the BNT/BNT-primed participants, the median ages were 51 years (41–59) in the younger age group and 78 years (75–82) in the older age group. In the ChAd/ChAD-primed group, 676 (46·7%) participants were female and 1380 (95·4%) were White, and in the BNT/BNT-primed group 770 (53·6%) participants were female and 1321 (91·9%) were White. Three vaccines showed overall increased reactogenicity: m1273 after ChAd/ChAd or BNT/BNT; and ChAd and Ad26 after BNT/BNT. For ChAd/ChAd-primed individuals, spike IgG geometric mean ratios (GMRs) between study vaccines and controls ranged from 1·8 (99% CI 1·5–2·3) in the half VLA group to 32·3 (24·8–42·0) in the m1273 group. GMRs for wild-type cellular responses compared with controls ranged from 1·1 (95% CI 0·7–1·6) for ChAd to 3·6 (2·4–5·5) for m1273. For BNT/BNT-primed individuals, spike IgG GMRs ranged from 1·3 (99% CI 1·0–1·5) in the half VLA group to 11·5 (9·4–14·1) in the m1273 group. GMRs for wild-type cellular responses compared with controls ranged from 1·0 (95% CI 0·7–1·6) for half VLA to 4·7 (3·1–7·1) for m1273. The results were similar between those aged 30–69 years and those aged 70 years and older. Fatigue and pain were the most common solicited local and systemic adverse events, experienced more in people aged 30–69 years than those aged 70 years or older. Serious adverse events were uncommon, similar in active vaccine and control groups. In total, there were 24 serious adverse events: five in the control group (two in control group A, three in control group B, and zero in control group C), two in Ad26, five in VLA, one in VLA-half, one in BNT, two in BNT-half, two in ChAd, one in CVn, two in NVX, two in NVX-half, and one in m1273.
Interpretation:
All study vaccines boosted antibody and neutralising responses after ChAd/ChAd initial course and all except one after BNT/BNT, with no safety concerns. Substantial differences in humoral and cellular responses, and vaccine availability will influence policy choices for booster vaccination.
Funding:
UK Vaccine Taskforce and National Institute for Health Research