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BACKGROUND:Cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) can provide unique data on the transmural extent of scar/viability. We assessed the prevalence of dysfunctional myocardium, including partial thickness scar, which could contribute to left ventricular contractile dysfunction in patients with heart failure and ischaemic heart disease who denied angina symptoms.METHODS:We invited patients with ischaemic heart disease and a left ventricular ejection fraction < 50% by echocardiography to have LGE CMR. Myocardial contractility and transmural extent of scar were assessed using a 17-segment model.RESULTS:The median age of the 193 patients enrolled was 70 (interquartile range: 63-76) years and 167 (87%) were men. Of 3281 myocardial segments assessed, 1759 (54%) were dysfunctional, of which 581 (33%) showed no scar, 623 (35%) had scar affecting 50% of wall thickness. Of 1522 segments with normal contractile function, only 98 (6%) had evidence of scar on CMR. Overall, 182 (94%) patients had >/=1 and 107 (55%) patients had >/=5 segments with contractile dysfunction that had no scar or 50% of the wall thickness affected by scar, suggesting that most dysfunctional segments could improve in response to an appropriate intervention. [ABSTRACT FROM AUTHOR]

Appended bispecific antibody (aBsAb) with two single chain variable fragments (scFv) linked at the c-terminus of its heavy chains is one of the promising formats in bispecific therapeutics. The presence of hydrophobic and flexible scFv fragments render aBsAb molecules higher molecule hydrophobicity and structural flexibility compared to monoclonal antibody (mAb), thus making its purification more challenging. We set out to investigate how the unique molecular properties of aBsAb affect its performance on Protein A chromatography. We showed that aBsAb has a high propensity for chromatography-induced aggregation due to its high molecule hydrophobicity, and this couldn't be improved by the addition of common chaotropic salts. Moreover, the presence of chaotropic salts, such as arginine hydrochloride (Arg-HCl), retarded aBsAb elution during Protein A chromatography rather than facilitating which was widely observed in mAb Protein A elution. Nevertheless, we were able to overcome the aggregation issue by optimizing elution condition and improved aBsAb purity from 29 % to 93 % in Protein A eluate with a high molecular weight (HMW) species of less than 5 %. We also showed that the high molecular flexibility of aBsAb leads to different hydrodynamic sizes of the aBsAb molecule post Protein A elution, neutralization, and re-acidification, which are pH dependent. This is different from mAbs where their sizes do not change post neutralization even with re-exposure to acid. The above unique observations of aBsAb in Protein A chromatography were clearly explained from the perspectives of its high molecular hydrophobicity and structural flexibility., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bispecific antibodies (bsAbs) hold promises for enhanced therapeutic potential surpassing that of their parental monoclonal antibodies. However, bsAbs pose great challenges in their manufacturing, and one of the common reasons is their susceptibility to aggregation. Building on previous studies demonstrating the functionality and potential manufacturability of Fab-scFv format bsAb, this investigation delved into the impact of environmental factors-such as pH, buffer types, ionic strength, protein concentrations, and temperatures-on its stability and the reversal of its self-associated aggregates. Mildly acidic, low-salt conditions were found optimal, ensuring bsAb stability for 30 days even at elevated temperature of 40 °C. Furthermore, these conditions facilitated the reversal of its self-associated aggregates to monomers during the initial 7-day incubation period. Our findings underscore the robustness and resilience of Fab-scFv format bsAb, further confirming its potential manufacturability despite its current absence as commercial products., (© 2024. The Author(s).)

Background: The aim of the study was to measure empathy in healthcare professionals in Singapore and to compare the scores between the different professions: doctors, nurses, and allied health professionals., Methods: An online survey questionnaire was conducted using the Jefferson Scale of Empathy (JSE) from July 2019 to January 2020. The total JSE score was calculated and compared among the different groups. Multiple linear regression was performed to assess predictors of total empathy scores for groups with statistically lower scores., Results: The survey was completed by 4,188 healthcare professionals (doctors (n=569, 13.6%), nurses (n=3032, 72.4%), and allied health professionals (n=587, 14.0%)) out of the 9,348-strong survey population, with a response rate of 44.8%. The study revealed a mean empathy score (SD) of 103.6 (15.6) for the cohort. The mean empathy score (SD) was 112.3 (14.7), 101.3 (15.2), and 107.0 (15.0), respectively for doctors, nurses, and allied health professionals. These were statistically significantly different among the groups (p< 0.0001), with nurses scoring significantly lower than either doctors (p< 0.0001) or allied health professionals (p< 0.0001). Multiple linear regression showed that age < 30 years old, male gender, Malay ethnicity, and working in a hospital setting were associated with significantly lower empathy scores in the nursing group., Conclusion: Nurses in Singapore had significantly lower empathy scores compared to doctors and allied health professionals. Further research on the underlying causes should be undertaken and measures to improve empathy among Singapore nursing staff should be explored and implemented., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, He et al.)

Plasmodium parasites contribute to one of the highest global infectious disease burdens. To achieve this success, the parasite has evolved a range of specialized subcellular compartments to extensively remodel the host cell for its survival. The information to fully understand these compartments is likely hidden in the so far poorly characterized Plasmodium species spatial proteome. To address this question, we determined the steady-state subcellular location of more than 12,000 parasite proteins across five different species by extensive subcellular fractionation of erythrocytes infected by Plasmodium falciparum, Plasmodium knowlesi, Plasmodium yoelii, Plasmodium berghei, and Plasmodium chabaudi. This comparison of the pan-species spatial proteomes and their expression patterns indicates increasing species-specific proteins associated with the more external compartments, supporting host adaptations and post-transcriptional regulation. The spatial proteome offers comprehensive insight into the different human, simian, and rodent Plasmodium species, establishing a powerful resource for understanding species-specific host adaptation processes in the parasite., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

T-cell-engaging bispecific antibodies (T-bsAbs) are promising immunotherapies for cancer treatment due to their capability of redirecting T-cells toward destroying tumor cells. Numerous T-bsAb formats have been developed, each with advantages and disadvantages in terms of developability, immunogenicity, effector functions, and pharmacokinetics. Here, we systematically compared T-bsAbs produced using eight different formats, evaluating the effect of molecular design of T-bsAbs on their manufacturability and functionality. These eight T-bsAb formats were constructed using antigen-binding fragments (Fabs) and single-chain variable fragments (scFvs) of antibodies linked to the crystallizable fragment (Fc) domain of immunoglobulin G. To ensure a fair comparison of growth and production data, we used recombinase-mediated cassette exchange technology to generate the T-bsAb-producing CHO cell lines. The produced T-bsAbs were assessed for their purification profile and recovery, binding capability, and biological activities. Our findings indicated that the manufacturability of bsAbs was adversely affected with increased number of scFv building blocks, while the functionality was affected by the combination of multiple factors, including the binding affinity and avidity of targeting moieties and the flexibility and geometry of formats. These results provide valuable insights into the impact of the format design on the optimal production and function of T-bsAbs.

Therapies using mesenchymal stromal cells (MSCs) to treat immune and inflammatory conditions are now at an exciting stage of development, with many MSC-based products progressing to phase II and III clinical trials. However, a major bottleneck in the clinical translation of allogeneic MSC therapies is the variable immunomodulatory properties of MSC products due to differences in their tissue source, donor heterogeneity and processes involved in manufacturing and banking. This variable functionality of MSC products likely contributes to the substantial inconsistency observed in the clinical outcomes of phase III trials of MSC therapies; several trials have failed to reach the primary efficacy endpoint. In this review, we discuss various strategies to consistently maintain or enhance the immunomodulatory potency of MSCs during ex vivo expansion, which will enable the manufacture of allogeneic MSC banks that have high potency and low variability. Biophysical and biochemical priming strategies, the use of culture additives such as heparan sulfates, and genetic modification can substantially enhance the immunomodulatory properties of MSCs during in vitro expansion. Furthermore, robust donor screening, the use of biomarkers to select for potent MSC subpopulations, and rigorous quality testing to improve the release criteria for MSC banks have the potential to reduce batch-to-batch heterogeneity and enhance the clinical efficacy of the final MSC product. Machine learning approaches to develop predictive models of individual patient response can enable personalized therapies and potentially establish correlations between in vitro potency measurements and clinical outcomes in human trials., Competing Interests: Competing Interests Statement The authors have no competing interests to declare., (Copyright © 2022 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

The genomes of Plasmodium spp. encode a number of different multigene families that are thought to play a critical role for survival. However, with the exception of the P. falciparum var genes, very little is known about the biological roles of any of the other multigene families. Using the recently developed Selection Linked Integration method, we have been able to activate the expression of a single member of a multigene family of our choice in Plasmodium spp. from its endogenous promoter. We demonstrate the usefulness of this approach by activating the expression of a unique var, rifin and stevor in P. falciparum as well as yir in P. yoelii. Characterization of the selected parasites reveals differences between the different families in terms of mutual exclusive control, co-regulation, and host adaptation. Our results further support the application of the approach for the study of multigene families in Plasmodium and other organisms.

Efforts to develop vaccines against malaria represent a major research target. The observations that 1) sterile protection can be obtained when the host is exposed to live parasites and 2) the immunity against blood stage parasite is principally mediated by protective antibodies suggest that a protective vaccine is feasible. However, only a small number of proteins have been investigated so far and most of the Plasmodium proteome has yet to be explored. To date, only few immunodominant antigens have emerged for testing in clinical trials but no formulation has led to substantial protection in humans. The nature of parasite molecules associated with protection remains elusive. Here, immunomic screening of mice immune sera with different protection efficiencies against the whole parasite proteome allowed us to identify a large repertoire of antigens validated by screening a library expressing antigens. The calculation of weighted scores reflecting the likelihood of protection of each antigen using five predictive criteria derived from immunomic and proteomic data sets, highlighted a priority list of protective antigens. Altogether, the approach sheds light on conserved antigens across Plasmodium that are amenable to targeting by the host immune system upon merozoite invasion and blood stage development. Most of these antigens have preliminary protection data but have not been widely considered as candidate for vaccine trials, opening new perspectives that overcome the limited choice of immunodominant, poorly protective vaccines currently being the focus of malaria vaccine researches., (© 2019 Siau et al.)

Communication and other nontechnical skills can affect the number of adverse events occurring in perioperative areas. Our study assessed the properties of the Scrub Practitioners' List of Intraoperative Non-Technical Skills (SPLINTS) used to assess nontechnical skills of scrub nurses in a diverse Asian ophthalmic ambulatory setting. We evaluated the content validation index, cultural equivalence index, concurrent validity, interrater reliability, test-retest reliability, internal consistency, and concurrent validity. The content validity and cultural equivalence indices were 0.93 and 0.91, respectively. We found that the tool showed acceptable interrater reliability, acceptable test-retest reliability, and an appropriate Cronbach alpha ranging from 0.80 to 0.88. We found satisfactory concurrent validity between the SPLINTS and the communication and teamwork scale assessment (r s = 0.73, P < .001) and clinical teamwork scale (r s = 0.64, P < .001). We concluded that SPLINTS is a sound psychometric tool for assessing the nontechnical skills of culturally-diverse scrub persons in ambulatory surgery settings., (© AORN, Inc, 2019.)

Purpose Wrong lens implants have been associated with the highest frequency of medical errors in cataract surgery. The purpose of this paper is to explore the use of the Systems Engineering Initiative for Patient Safety (SEIPS) framework to sustainably reduce wrong intraocular lens (IOL) implants in cataract surgery. Design/methodology/approach In this mixed-methods study, the SEIPS framework was used to analyse a series of (near) misses of IOL implants in a national tertiary specialty hospital in Singapore. A series of interventions was developed and applied in the case hospital. Risk assessment audits were done before the interventions (2012; n=6,111 surgeries), during its implementation ( n=7,475) and in the two years post-interventions (2013-2015; n=39,390) to compare the wrong IOL-rates. Findings Although the absolute number of incidents was low, the incident rate decreased from 4.91 before to 2.54 per 10,000 cases after. Near miss IOL error decreased from 5.89 before to 3.55 per 1,000 cases after. The number of days between two IOL incidents increased from 35 to an initial peak of 385 before stabilizing on 56. The large variety of available IOL types and vendors was found as the main root cause of wrong implants that required reoperation. Practical implications The SEIPS framework seems to be helpful to assess components involved and develop sustainable quality and safety interventions that intervene at different levels of the system. Originality/value The SEIPS model is supportive to address differences between person and system root causes comprehensively and thereby foster quality and patient safety culture.

Introduction: Chloral hydrate (CH) sedation is routinely used in paediatric ophthalmic examination in Singapore as an alternative to examination under general anaesthesia. Despite CH's traditionally high success rates and relatively low rate of adverse events, there is little data on its safety and efficacy as a sedative for ophthalmic procedures in an Asian population., Materials and Methods: A retrospective chart review was performed, including children who underwent CH sedation at the Singapore National Eye Centre from January 2012 to January 2015. Participants were given an initial dose of CH and a top-up dose if required. Univariate and multivariate analyses were performed on data collected., Results: CH sedation was successful in 144 of 153 children (94.1%). Of the 20 (13.0%) who required a top-up dose, 4 failed to sedate. The mean sedation onset was 29.4 minutes (SD: 24.3) and mean sedation duration was 56.5 minutes (SD: 24.0), with more than a third lasting more than 1 hour. The age of children, rather than initial dose of CH, was more relevant in determining success of sedation. Children who were >6 years old were 20.3 times more likely to fail sedation than those aged <2 years. During sedation, depression in the heart rate and a transient reduction of oxygen saturation was documented. All children recovered well post-sedation., Conclusion: CH is a very useful sedative for paediatric ophthalmic procedures, especially in younger children. Children over 4 years old were more likely to fail sedation and require top-up doses. Alternative means of sedation may need to be considered in these cases.

Aortic atherosclerosis reduces compliance in the systemic circulation and increases peripheral resistance, afterload and left ventricular wall stress. In patients with heart failure, these changes can impair left ventricular systolic function and energy efficiency, which could reduce exercise capacity. Though the interaction and the impact of aortic atherosclerosis on left ventricular function have been investigated, its prognostic implications in patients with heart failure are unclear. We used cardiac magnetic resonance imaging and gadolinium-enhanced abdominal aortography to investigate the prevalence and prognostic impact of atherosclerotic disease of the abdominal aorta and its side branches in 355 patients with heart failure. Sclerotic abdominal aortic disease was defined as a luminal narrowing >50% of the aorta and its side branches or the presence of abdominal aortic aneurysm. Patients with disease of the aorta and its branches were older (P < 0.0001), had overall longer stay in hospital (P = 0.006) and had more admissions (P = 0.001) and worse prognosis (hazard ratio: 1.97, 95% confidence interval: 1.29-3.00, P = 0.002) than those without. In a multivariable model, increasing age and pulse pressure, diabetes mellitus and increasing left ventricular end-diastolic volume were associated with a worse prognosis, but sclerotic abdominal aortic disease was not independently related to outcome (hazard ratio: 1.06; 95% confidence interval: 0.64-1.74; P = 0.823). These data demonstrate that atherosclerosis of the abdominal aorta and its side branches is common and associated with increased morbidity in patients with chronic heart failure. How such disease should be managed remains uncertain, but its recognition and characterisation are the first steps in finding out.

Aims: The aim of this study was to investigate the prognostic impact of right ventricular (RV) size in patients with chronic heart failure., Methods and Results: Normal volunteers (n = 80) and patients (n = 380) with left ventricular (LV) ejection fraction <45% on echocardiography and on optimal treatment for heart failure underwent cardiac magnetic resonance imaging with measurement of LV and RV volumes, mass and ejection fraction. The mean and the standard deviation (SD) of the RV end-systolic volume index in normal subjects were used to define the normal range as: mean RV end-systolic volume index +2 SD. Patients with dilated RV (>2 SD beyond the mean) (25%) had more frequent evidence of fluid overload in clinical examination and greater LV dimensions (P < 0.0001). During follow-up (median 45, interquartile range: 28-66 months), 37% of patients with and 24% without RV dilation died (log-rank test = 8.4; P = 0.004). In a multivariable Cox regression model, including 13 other clinical variables, RV (HR: 1.08/10 mL/m(2), 95% CI: 1.00-1.18, P = 0.044), but not LV, end-systolic volume index predicted a worse outcome., Conclusion: Twenty-five per cent of patients with heart failure due to LV systolic dysfunction have a dilated right ventricle. Greater RV dimensions predict mortality in patients with chronic heart failure. Treatments aimed at preserving or enhancing RV structure and function, possibly by unloading the RV by reducing pulmonary vascular resistance or left atrial pressure, should be investigated.