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1.
Front Psychol ; 14: 1320703, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38090173

RESUMEN

The average working person spends between 35 and 60 h a week in the workplace, making it an influential place for mental well-being and a place for socioeconomic contribution. Workplace incivility can diminish positive mental health outcomes and negatively impact work engagement through increased social anxiety. To investigate this, 118 working adults in Singapore aged between 19 to 67 years old were recruited for a survey consisting of demographic questions, the Workplace Incivility Scale, the Brief DSM-5 Social Anxiety Disorder Severity Scale, and the Utrecht Work Engagement Scale-9 between November 2022 to April 2023. Correlational, regression, and mediation analysis showed workplace incivility scale scores to significantly predict social anxiety after controlling for covariates. This supports our hypothesis that employees exposed to workplace incivility would have higher social anxiety levels mediating work engagement after controlling for age and gender. The findings here show workplace incivility as a possible intervention target for social anxiety, in order to reduce negative impact on work engagement to improve employee experience and retention for organizations.

2.
Antib Ther ; 6(3): 182-193, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37680351

RESUMEN

As the most abundant immunoglobulin in blood and the most common human isotype used for therapeutic monoclonal antibodies, the engagement and activation of its Fc receptors by IgGs are crucial for antibody function. Assumed to be relatively constant within subtypes, recent studies reveal that antibody variable regions exert distal effects of modulating antibody-receptor interactions on antibody isotypes. These variable (V)-region distal effects are also expected for the IgG subtypes. With an in-depth understanding of the V-region effects, researchers can make a more informed antibody engineering approach and antibody purification strategy accounting for the functions of microbial immune evasion . In this study, we created a panel of IgG2/IgG3/IgG4 antibodies by changing the VH family (VH1-7) frameworks while retaining the complementary determining regions of pertumuzab and measured their interactions with FcγRIa, FcγRIIaH167, FcγRIIaR167, FcγRIIb/c, FcγRIIIaF176, FcγRIIIaV176, FcγRIIIbNA1 and FcγRIIIbNA2 receptors alongside B-cell superantigens Protein L and G using biolayer interferometry. The panel of 21 IgGs demonstrated that the VH frameworks influenced receptor binding sites on the constant region in a non-canonical manner. However, there was minimal influence on the binding of bacterial B-cell superantigens Proteins L and Protein G on the IgGs, showing their robustness against V-region effects. These results demonstrate the role of V-regions during the humanization of therapeutic antibodies that can influence FcR-dependent immune responses while retaining binding by bacterial B-cell superantigens for antibody purification. These in vitro measurements provide a clue to detailed antibody engineering and understanding of antibody superantigen functions that would be relevant with in vivo validation.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36834313

RESUMEN

The COVID-19 pandemic infection control measures severely impacted mental well-being, allowing insight into possible protective parameters. With religion playing a role during challenging times, this study investigated theism and religiosity on the mental well-being of university students during the COVID19 pandemic and how social support and resilience can mediate this effect. One hundred eighty-five university students between 17 and 42 years old responded to online surveys on their theism, religious affiliations, religiosity, well-being, perceived support, and resilience. Pearson's correlations and single and sequential mediation analyses showed that theism did not significantly predict well-being (r = 0.049), but religiosity mediated the relationship (r = 0.432, effect size = 0.187). Sequential mediation analysis showed that resilience did not mediate the relationship between religiosity and well-being, but perceived social support significantly positively mediated religiosity and well-being with an effect size of 0.079. The findings reveal that factors, such as religiosity and social support could thus aid in the mental well-being of future challenging times such as the pandemic.


Asunto(s)
COVID-19 , Pandemias , Humanos , Adolescente , Adulto Joven , Adulto , Universidades , Singapur , Religión , Estudiantes , Apoyo Social
4.
Biochem Mol Biol Educ ; 50(4): 403-413, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35621717

RESUMEN

The COVID-19 pandemic related measures had augmented the rise of online education. While online teaching had mitigated the negative impacts from educational institutional closures, it was unable to displace hands-on biomedical laboratory practical lessons effectively. Without practical sessions, there was concern over the imparting of laboratory skills even with video demonstrations. To investigate the effectiveness of different delivery modes in imparting laboratory skills, theoretical and practical student assessments were analyzed alongside an anonymous survey on their motivation and prior experience. The undergraduate students were exposed to (1) instructor-live demonstration; (2) video demonstration or (3) no demonstration prior to the practical test which was a plasmid extraction. Significantly higher mini-prep yields and purity were found for both instructor-live and video demonstrations compared to no demonstration. Comparison with pre-pandemic theoretical assessment performance showed no significant differences despite longer contact hours during pre-pandemic times. Prior lab experience and motivation for selecting the course did not significantly affect student mini-prep yields. In conclusion, our findings suggest that video demonstrations were as effective as instructor-live demonstrations during the pandemic without noticeably compromising the teaching and learning of biomedical laboratory skills.


Asunto(s)
COVID-19 , Educación a Distancia , COVID-19/epidemiología , Evaluación Educacional , Humanos , Aprendizaje , Pandemias , Enseñanza
5.
Sci Rep ; 12(1): 6510, 2022 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-35444201

RESUMEN

Interest in IgA as an alternative antibody format has increased over the years with much remaining to be investigated in relation to interactions with immune cells. Considering the recent whole antibody investigations showing significant distal effects between the variable (V) and constant (C)- regions that can be mitigated by the hinge regions of both human IgA subtypes A1 and A2, we performed an in-depth mechanistic investigation using a panel of 28 IgA1s and A2s of both Trastuzumab and Pertuzumab models. FcαRI binding were found to be mitigated by the differing glycosylation patterns in IgA1 and 2 with contributions from the CDRs. On their interactions with antigen-Her2 and superantigens PpL, SpG and SpA, PpL was found to sterically hinder Her2 antigen binding with unexpected findings of IgAs binding SpG at the CH2-3 region alongside SpA interacting with IgAs at the CH1. Although the VH3 framework (FWR) is commonly used in CDR grafting, we found the VH1 framework (FWR) to be a possible alternative when grafting IgA1 and 2 owing to its stronger binding to antigen Her2 and weaker interactions to superantigen Protein L and A. These findings lay the foundation to understanding the interactions between IgAs and microbial superantigens, and also guide the engineering of IgAs for future antibody applications and targeting of superantigen-producing microbes.


Asunto(s)
Inmunoglobulina A , Superantígenos , Antígenos , Humanos , Inmunoglobulina A/metabolismo , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Oncogenes
6.
Antib Ther ; 5(1): 63-72, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35372784

RESUMEN

The target of an antibody plays a significant role in the success of antibody-based therapeutics and diagnostics, and vaccine development. This importance is focused on the target binding site-epitope, where epitope selection as a part of design thinking beyond traditional antigen selection using whole cell or whole protein immunization can positively impact success. With purified recombinant protein production and peptide synthesis to display limited/selected epitopes, intrinsic factors that can affect the functioning of resulting antibodies can be more easily selected for. Many of these factors stem from the location of the epitope that can impact accessibility of the antibody to the epitope at a cellular or molecular level, direct inhibition of target antigen activity, conservation of function despite escape mutations, and even noncompetitive inhibition sites. By incorporating novel computational methods for predicting antigen changes to model-informed drug discovery and development, superior vaccines and antibody-based therapeutics or diagnostics can be easily designed to mitigate failures. With detailed examples, this review highlights the new opportunities, factors, and methods of predicting antigenic changes for consideration in sagacious epitope selection.

8.
Antibodies (Basel) ; 11(1)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35225872

RESUMEN

Immunoglobulin superantigens play an important role in affinity purification of antibodies and the microbiota-immune axis at mucosal areas. Based on current understanding, Staphylococcal Protein A (SpA), Streptococcal Protein G (SpG) and Finegoldia Protein L (PpL) are thought to only bind specific regions of human antibodies, allowing for selective purification of antibody isotypes and chains. Clinically, these superantigens are often classified as toxins and increase the virulence of the producing pathogen through unspecific interactions with immune proteins. To perform an in-depth interaction study of these three superantigens with antibodies, bio-layer interferometry (BLI) measurements of their interactions with a permutation panel of 63 IgG1 variants of Pertuzumab and Trastuzumab CDRs grafted to the six human Vκ and seven human VH region families were tested. Through this holistic and systemic analysis of IgG1 variants with various antibody regions modified, comparisons revealed novel PpL-antibody interactions influenced by other non-canonical antibody known light-chain framework regions, whereas SpA and SpG showed relatively consistent interactions. These findings have implications on PpL-based affinity antibody purification and design that can guide the engineering and understanding of PpL-based microbiota-immune effects.

9.
Antib Ther ; 5(1): 30-41, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35146331

RESUMEN

BACKGROUND: Optimizing recombinant antibody production is important for cost-effective therapeutics and diagnostics. With impact on commercialization, higher productivity beyond laboratory scales is highly sought, where efficient production can also accelerate antibody characterizations and investigations. METHODS: Investigating HEK293E cells for mammalian antibody production, various transfection and culture parameters were systematically analyzed for antibody light chain production before evaluating them for whole antibody production. Transfection parameters investigated include seeding cell density, the concentration of the transfection reagent and DNA, complexation time, temperature, and volume, as well as culture parameters such as medium replacement, serum deprivation, use of cell maintenance antibiotic, incubation temperature, medium volume, post-transfection harvest day, and common nutrient supplements. RESULTS: Using 2 mL adherent HEK293E cell culture transfections with 25 kDa linear polyethylenimine in the most optimized parameters, we demonstrated a ~2-fold production increase for light chain alone and for whole antibody production reaching 536 and 49 µg, respectively, in a cost-effective manner. With the addition of peptone, κ light chain increased by ~4-fold to 1032 µg, whereas whole antibody increased to a lesser extent by ~2.5-fold to 51 µg, with benefits potentially for antibodies limited by their light chains in production. CONCLUSIONS: Our optimized findings show promise for a more efficient and convenient antibody production method through transfection and culture optimizations that can be incorporated to scale-up processes and with potential transferability to other mammalian-based recombinant protein production using HEK293E.

10.
Methods Protoc ; 6(1)2022 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-36648950

RESUMEN

Protein display, secretion, and export in prokaryotes are essential for utilizing microbial systems as engineered living materials, medicines, biocatalysts, and protein factories. To select for improved signal peptides for Escherichia coli protein display, we utilized error-prone polymerase chain reaction (epPCR) coupled with single-cell sorting and microplate titer to generate, select, and detect improved Ag43 signal peptides. Through just three rounds of mutagenesis and selection using green fluorescence from the 56 kDa sfGFP-beta-lactamase, we isolated clones that modestly increased surface display from 1.4- to 3-fold as detected by the microplate plate-reader and native SDS-PAGE assays. To establish that the functional protein was displayed extracellularly, we trypsinized the bacterial cells to release the surface displayed proteins for analysis. This workflow demonstrated a fast and high-throughput method leveraging epPCR and single-cell sorting to augment bacterial surface display rapidly that could be applied to other bacterial proteins.

11.
Viruses ; 13(11)2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34835082

RESUMEN

2014 marked the first emergence of avian influenza A(H5N8) in Jeonbuk Province, South Korea, which then quickly spread worldwide. In the midst of the 2020-2021 H5N8 outbreak, it spread to domestic poultry and wild waterfowl shorebirds, leading to the first human infection in Astrakhan Oblast, Russia. Despite being clinically asymptomatic and without direct human-to-human transmission, the World Health Organization stressed the need for continued risk assessment given the nature of Influenza to reassort and generate novel strains. Given its promiscuity and easy cross to humans, the urgency to understand the mechanisms of possible species jumping to avert disastrous pandemics is increasing. Addressing the epidemiology of H5N8, its mechanisms of species jumping and its implications, mutational and reassortment libraries can potentially be built, allowing them to be tested on various models complemented with deep-sequencing and automation. With knowledge on mutational patterns, cellular pathways, drug resistance mechanisms and effects of host proteins, we can be better prepared against H5N8 and other influenza A viruses.


Asunto(s)
Subtipo H5N8 del Virus de la Influenza A/genética , Gripe Aviar/virología , Enfermedades de las Aves de Corral/virología , Animales , Aves/virología , Humanos , Gripe Aviar/epidemiología , Pandemias/veterinaria , Filogenia , Aves de Corral/virología , Enfermedades de las Aves de Corral/epidemiología , República de Corea/epidemiología , Federación de Rusia/epidemiología
12.
Front Immunol ; 12: 731845, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34616400

RESUMEN

Superantigens are unconventional antigens which recognise immune receptors outside their usual recognition sites e.g. complementary determining regions (CDRs), to elicit a response within the target cell. T-cell superantigens crosslink T-cell receptors and MHC Class II molecules on antigen-presenting cells, leading to lymphocyte recruitment, induction of cytokine storms and T-cell anergy or apoptosis among many other effects. B-cell superantigens, on the other hand, bind immunoglobulins on B-cells, affecting opsonisation, IgG-mediated phagocytosis, and driving apoptosis. Here, through a review of the structural basis for recognition of immune receptors by superantigens, we show that their binding interfaces share specific physicochemical characteristics when compared with other protein-protein interaction complexes. Given that antibody-binding superantigens have been exploited extensively in industrial antibody purification, these observations could facilitate further protein engineering to optimize the use of superantigens in this and other areas of biotechnology.


Asunto(s)
Células Presentadoras de Antígenos/metabolismo , Linfocitos B/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Fragmentos de Inmunoglobulinas/metabolismo , Activación de Linfocitos , Receptores de Antígenos de Linfocitos T/metabolismo , Superantígenos/metabolismo , Linfocitos T/metabolismo , Animales , Anticuerpos/aislamiento & purificación , Células Presentadoras de Antígenos/inmunología , Apoptosis , Linfocitos B/inmunología , Linfocitos B/patología , Anergia Clonal , Síndrome de Liberación de Citoquinas/inmunología , Síndrome de Liberación de Citoquinas/metabolismo , Antígenos de Histocompatibilidad Clase II/inmunología , Humanos , Fragmentos de Inmunoglobulinas/inmunología , Ingeniería de Proteínas , Receptores de Antígenos de Linfocitos T/inmunología , Transducción de Señal , Superantígenos/inmunología , Linfocitos T/inmunología , Linfocitos T/patología
13.
Front Immunol ; 12: 676048, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34305906

RESUMEN

The binding of nickel by immune proteins can manifest as Type IV contact dermatitis (Ni-specific T cells mediated) and less frequently as Type I hypersensitivity with both mechanisms remaining unknown to date. Since there are reports of patients co-manifesting the two hypersensitivities, a common mechanism may underlie both the TCR and IgE nickel binding. Focusing on Trastuzumab and Pertuzumab IgE variants as serendipitous investigation models, we found Ni-NTA interactions independent of Her2 binding to be due to glutamine stretches. These stretches are both Ni-inducible and in fixed pockets at the antibody complementarity-determining regions (CDRs) and framework regions (FWRs) of both the antibody heavy and light chains with influence from the heavy chain constant region. Comparisons with TCRs structures revealed similar interactions, demonstrating the possible underlying mechanism in selecting for Ni-binding IgEs and TCRs respectively. With the elucidation of the interaction, future therapeutic antibodies could also be sagaciously engineered to utilize such nickel binding for biotechnological purposes.


Asunto(s)
Hipersensibilidad/etiología , Inmunoglobulina E/inmunología , Níquel/inmunología , Superantígenos/inmunología , Anticuerpos Monoclonales Humanizados/química , Regiones Determinantes de Complementariedad , Células HEK293 , Humanos , Inmunoglobulina E/química , Cadenas Pesadas de Inmunoglobulina/química , Región Variable de Inmunoglobulina/química , Níquel/química , Receptores de Antígenos de Linfocitos T/inmunología , Trastuzumab/química
14.
Methods Protoc ; 4(2)2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34207547

RESUMEN

Despite the public availability, finding experts in any field when relying on academic publications can be challenging, especially with the use of jargons. Even after overcoming these issues, the discernment of expertise by authorship positions is often also absent in the many publication-based search platforms. Given that it is common in many academic fields for the research group lead or lab head to take the position of the last author, some of the existing authorship scoring systems that assign a decreasing weightage from the first author would not reflect the last author correctly. To address these problems, we incorporated natural language processing (Common Crawl using fastText) to retrieve related keywords when using jargons as well as a modified authorship positional scoring that allows the assignment of greater weightage to the last author. The resulting output is a ranked scoring system of researchers upon every search that we implemented as a webserver for internal use called the APD lab Capability & Expertise Search (ACES).

15.
Methods Protoc ; 4(2)2021 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-34205648

RESUMEN

Polystyrene (PS) is one of the major plastics contributing to environmental pollution with its durability and resistance to natural biodegradation. Recent research showed that mealworms (Tenebrio molitor) and superworms (Zophobas morio) are naturally able to consume PS as a carbon food source and degrade them without observable toxic effects. In this study, we explored the effects of possible food additives and use of worm frass as potential plant fertilizers. We found that small amounts of sucrose and bran increased PS consumption and that the worm frass alone could support dragon fruit cacti (Hylocereus undatus) growth, with superworm frass in particular, supporting better growth and rooting than mealworm frass and control media over a fortnight. As known fish and poultry feed, these findings present worms as a natural solution to simultaneously tackle both the global plastic problem and urban farming issue in a zero-waste sustainable bioremediation cycle.

16.
Sensors (Basel) ; 21(11)2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34073031

RESUMEN

Fever is a common symptom of many infections, e.g., in the ongoing COVID-19 pandemic, keeping monitoring devices such as thermometers in constant demand. Recent technological advancements have made infrared (IR) thermometers the choice for contactless screening of multiple individuals. Yet, even so, the measurement accuracy of such thermometers is affected by many factors including the distance from the volunteers' forehead, impurities (such as sweat), and the location measured on the volunteers' forehead. To overcome these factors, we describe the assembly of an Arduino-based digital IR thermometer with distance correction using the MLX90614 IR thermometer and HC-SR04 ultrasonic sensors. Coupled with some analysis of these factors, we also found ways to programme compensation methods for the final assembled digital IR thermometer to provide more accurate readings and measurements.


Asunto(s)
COVID-19 , Termómetros , Temperatura Corporal , Humanos , Pandemias , SARS-CoV-2
17.
J Biomol Tech ; 32(2): 57-62, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34121935

RESUMEN

Many molecular biology applications require fast plasmid DNA extraction, spurring multiple studies on how to speed up the process. It is regularly instructed in standard laboratory protocols to plate out frozen glycerol bacterial stocks prior to bacteria incubation in liquid media and subsequent plasmid extraction, although the rationale for this is often unexplained (other than for the isolation of single colonies). Given the commonality and importance of this laboratory operation, such a practice is time-consuming and laborious. To study the impact of this practice and the alternative direct culturing method, we investigated the association between bacterial cell mass and its potential influence on plasmid yields from the 2 methods. Our results showed no difference with preplating for 7 out of 8 plasmid constructs used in the study, suggesting that direct glycerol recovery would not lead to poorer plasmid yields. The findings support the rationale for direct glycerol recovery for plasmid extraction, without the need of an intermediate preplating step.


Asunto(s)
Glicerol , Medios de Cultivo , Plásmidos/genética
18.
J Biomol Tech ; 32(1): 10-14, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-34025220

RESUMEN

Even with the ubiquity of Sanger sequencing, automated assembly software are predominantly stand-alone software packages for desktop/laptop use with very few online equivalents, thus geospatially constraining sequence analysis and assembly. With increased data output worldwide, there is also a need for automated quality checks and trimming prior to large assemblies, along with automated detection of mutations. Through web servers with expanded automation and functionalities, even smartphones/phablets can be used to perform complex analysis previously limited to desktops, especially if they can upload files from cloud storage. To facilitate such online accessible sequence assembly and analysis, we created Yet Another Quick Assembly, Analysis and Trimming Tool web server for the automated assembly of multiple .ab1 and .FASTQ sequencing reads de novo with automated trimming and scanning of the assembled sequences for single nucleotide polymorphisms and insertions or deletions without installation of software, allowing it to be accessed from anywhere with Internet access and with minimal dependency on other software and web tools.


Asunto(s)
Computadores , Programas Informáticos , Automatización
19.
J Biomol Tech ; 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33584150

RESUMEN

Even with the ubiquity of Sanger sequencing, automated assembly software are predominantly stand-alone software packages for desktop/laptop use with very few online equivalents, thus geospatially constraining sequence analysis and assembly. With increased data output worldwide, there is also a need for automated quality checks and trimming prior to large assemblies, along with automated detection of mutations. Through web servers with expanded automation and functionalities, even smartphones/phablets can be used to perform complex analysis previously limited to desktops, especially if they can upload files from cloud storage. To facilitate such online accessible sequence assembly and analysis, we created Yet Another Quick Assembly, Analysis and Trimming Tool web server for the automated assembly of multiple .ab1 and .FASTQ sequencing reads de novo with automated trimming and scanning of the assembled sequences for single nucleotide polymorphisms and insertions or deletions without installation of software, allowing it to be accessed from anywhere with Internet access and with minimal dependency on other software and web tools.

20.
Comput Struct Biotechnol J ; 19: 330-342, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33425260

RESUMEN

The high mutation rate in retroviruses is one of the leading causes of drug resistance. In human immunodeficiency virus type-1 (HIV-1), synergistic mutations in its protease and the protease substrate - the Group-specific antigen (Gag) polyprotein - work together to confer drug resistance against protease inhibitors and compensate the mutations affecting viral fitness. Some Gag mutations can restore Gag-protease binding, yet most Gag-protease correlated mutations occur outside of the Gag cleavage site. To investigate the molecular basis for this, we now report multiscale modelling approaches to investigate various sequentially cleaved Gag products in the context of clinically relevant mutations that occur outside of the cleavage sites, including simulations of the largest Gag proteolytic product in its viral membrane-bound state. We found that some mutations, such as G123E and H219Q, involve direct interaction with cleavage site residues to influence their local environment, while certain mutations in the matrix domain lead to the enrichment of lipids important for Gag targeting and assembly. Collectively, our results reveal why non-cleavage site mutations have far-reaching implications outside of Gag proteolysis, with important consequences for drugging Gag maturation intermediates and tackling protease inhibitor resistance.

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