RESUMO
Humans and other animals produce a diverse collection of antibodies, many of which bind to carbohydrate chains, referred to as glycans. These anti-glycan antibodies are a critical part of our immune systems' defenses. Whether induced by vaccination or natural exposure to a pathogen, anti-glycan antibodies can provide protection against infections and cancers. Alternatively, when an immune response goes awry, antibodies that recognize self-glycans can mediate autoimmune diseases. In any case, serum anti-glycan antibodies provide a rich source of information about a patient's overall health, vaccination history, and disease status. Glycan microarrays provide a high-throughput platform to rapidly interrogate serum anti-glycan antibodies and identify new biomarkers for a variety of conditions. In addition, glycan microarrays enable detailed analysis of the immune system's response to vaccines and other treatments. Herein we review applications of glycan microarray technology for serum anti-glycan antibody profiling.
Assuntos
Polissacarídeos , Vacinas , Animais , Humanos , Polissacarídeos/metabolismo , Anticorpos , Carboidratos , Análise em MicrossériesRESUMO
Traction-force microscopy (TFM) has emerged as a widely used standard methodology to measure cell-generated traction forces and determine their role in regulating cell behavior. While TFM platforms have enabled many discoveries, their implementation remains limited due to complex experimental procedures, specialized substrates, and the ill-posed inverse problem whereby low-magnitude high-frequency noise in the displacement field severely contaminates the resulting traction measurements. Here, we introduce deep morphology traction microscopy (DeepMorphoTM), a deep-learning alternative to conventional TFM approaches. DeepMorphoTM first infers cell-induced substrate displacement solely from a sequence of cell shapes and subsequently computes cellular traction forces, thus avoiding the requirement of a specialized fiduciarily marked deformable substrate or force-free reference image. Rather, this technique drastically simplifies the overall experimental methodology, imaging, and analysis needed to conduct cell-contractility measurements. We demonstrate that DeepMorphoTM quantitatively matches conventional TFM results while offering stability against the biological variability in cell contractility for a given cell shape. Without high-frequency noise in the inferred displacement, DeepMorphoTM also resolves the ill-posedness of traction computation, increasing the consistency and accuracy of traction analysis. We demonstrate the accurate extrapolation across several cell types and substrate materials, suggesting robustness of the methodology. Accordingly, we present DeepMorphoTM as a capable yet simpler alternative to conventional TFM for characterizing cellular contractility in two dimensions.
Assuntos
Microscopia , Microscopia/métodos , Fenômenos Biomecânicos , Animais , Aprendizado Profundo , Fenômenos Mecânicos , Camundongos , Forma Celular , HumanosRESUMO
For quality, interpretation, reproducibility and sharing value, microscopy images should be accompanied by detailed descriptions of the conditions that were used to produce them. Micro-Meta App is an intuitive, highly interoperable, open-source software tool that was developed in the context of the 4D Nucleome (4DN) consortium and is designed to facilitate the extraction and collection of relevant microscopy metadata as specified by the recent 4DN-BINA-OME tiered-system of Microscopy Metadata specifications. In addition to substantially lowering the burden of quality assurance, the visual nature of Micro-Meta App makes it particularly suited for training purposes.
Assuntos
Metadados , Microscopia Confocal/instrumentação , Microscopia Confocal/métodos , Microscopia de Fluorescência/instrumentação , Microscopia de Fluorescência/métodos , Aplicativos Móveis , Linguagens de Programação , Software , Animais , Linhagem Celular , Biologia Computacional/métodos , Humanos , Processamento de Imagem Assistida por Computador , Camundongos , Reconhecimento Automatizado de Padrão , Controle de Qualidade , Reprodutibilidade dos Testes , Interface Usuário-Computador , Fluxo de TrabalhoRESUMO
In the dynamic landscape of scientific research, imaging core facilities are vital hubs propelling collaboration and innovation at the technology development and dissemination frontier. Here, we present a collaborative effort led by Global BioImaging (GBI), introducing international recommendations geared towards elevating the careers of Imaging Scientists in core facilities. Despite the critical role of Imaging Scientists in modern research ecosystems, challenges persist in recognising their value, aligning performance metrics and providing avenues for career progression and job security. The challenges encompass a mismatch between classic academic career paths and service-oriented roles, resulting in a lack of understanding regarding the value and impact of Imaging Scientists and core facilities and how to evaluate them properly. They further include challenges around sustainability, dedicated training opportunities and the recruitment and retention of talent. Structured across these interrelated sections, the recommendations within this publication aim to propose globally applicable solutions to navigate these challenges. These recommendations apply equally to colleagues working in other core facilities and research institutions through which access to technologies is facilitated and supported. This publication emphasises the pivotal role of Imaging Scientists in advancing research programs and presents a blueprint for fostering their career progression within institutions all around the world.
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Pesquisadores , Humanos , Mobilidade Ocupacional , Pesquisa Biomédica/métodos , Escolha da ProfissãoRESUMO
This article outlines a global study conducted by the Association of Biomedical Resource Facilities (ABRF) Light Microscopy Research Group (LMRG). The results present a novel 3D tissue-like biologically relevant standard sample that is affordable and straightforward to prepare. Detailed sample preparation, instrument-specific image acquisition protocols and image analysis methods are presented and made available to the community. The standard consists of sub-resolution and large well characterized relative intensity fluorescence microspheres embedded in a 120 µm thick 3D gel with a refractive index of 1.365. The standard allows the evaluation of several properties as a function of depth. These include the following: 1) microscope resolution with automated analysis of the point-spread function (PSF), 2) automated signal-to-noise ratio analysis, 3) calibration and correction of fluorescence intensity loss, and 4) quantitative relative intensity. Results demonstrate expected refractive index mismatch dependent losses in intensity and resolution with depth, but the relative intensities of different objects at similar depths are maintained. This is a robust standard showing reproducible results across laboratories, microscope manufacturers and objective lens types (e.g., magnification, immersion medium). Thus, these tools will be valuable for the global community to benchmark fluorescence microscopes and will contribute to improved scientific rigor and reproducibility.
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Processamento de Imagem Assistida por Computador , Reprodutibilidade dos Testes , Microscopia de Fluorescência/métodosRESUMO
The initiation of chromosome morphogenesis marks the beginning of mitosis in all eukaryotic cells. Although many effectors of chromatin compaction have been reported, the nature and design of the essential trigger for global chromosome assembly remain unknown. Here we reveal the identity of the core mechanism responsible for chromosome morphogenesis in early mitosis. We show that the unique sensitivity of the chromosome condensation machinery for the kinase activity of Cdk1 acts as a major driving force for the compaction of chromatin at mitotic entry. This sensitivity is imparted by multisite phosphorylation of a conserved chromatin-binding sensor, the Smc4 protein. The multisite phosphorylation of this sensor integrates the activation state of Cdk1 with the dynamic binding of the condensation machinery to chromatin. Abrogation of this event leads to chromosome segregation defects and lethality, while moderate reduction reveals the existence of a novel chromatin transition state specific to mitosis, the intertwist configuration. Collectively, our results identify the mechanistic basis governing chromosome morphogenesis in early mitosis and how distinct chromatin compaction states can be established via specific thresholds of Cdk1 kinase activity.
Assuntos
Divisão Celular/genética , Cromossomos Fúngicos/genética , Quinases Ciclina-Dependentes/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Montagem e Desmontagem da Cromatina/genética , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Genes de Troca/fisiologia , Mitose , Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Fosforilação , Ligação Proteica , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMO
Evidence suggests that blood transfusion errors tend to occur because of an external stimulus, limiting control for the professional administering it. Whether it be cognitive bias, human traits, organisational or human factors, errors should be prevented because they put the safety of the patient at risk from major morbidity and mortality. The authors explored the literature that looked at the blood transfusion errors that occur, suggesting interventions that may have a positive impact on patient safety. A review of the literature was undertaken using key words and limiters to focus the search. The review found that, when practitioners do not perform skills or interventions regularly, competence diminishes. Training and rolling refresher programmes appeared to improve retention and knowledge, therefore enhancing patient safety. Consequently, the impact of human factors in the healthcare setting requires more comprehensive investigation. Nurses may have the knowledge and understanding regarding blood transfusions; however, the environment in which they work could contribute to the likelihood of errors.
Assuntos
Transfusão de Sangue , Segurança do Paciente , Humanos , Atenção à SaúdeRESUMO
The World Health Organization (2019) has determined that patient safety is a global public health challenge. In UK clinical areas, policies and procedures are in place for the safe prescribing and delivery of blood and blood product transfusions, yet patient safety incidences continue. Undergraduate nurse education and training may provide the underlying knowledge to practitioners, while postgraduate standalone training sessions support skill development. However, over time, without regular experience, competence will diminish. Nursing students may have little exposure to transfusion practice and COVID-19 may have exacerbated this challenge with a reduction in placement availability. The use of simulation to support theory with follow-up and ongoing drop-in training sessions may help to inform practitioners and improve patient safety in the management and delivery of blood and blood product transfusion.
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COVID-19 , Bacharelado em Enfermagem , Enfermeiras e Enfermeiros , Humanos , Transfusão de Sangue , Bacharelado em Enfermagem/métodos , Segurança do Paciente , Competência ClínicaRESUMO
Fluorescence illumination can cause phototoxicity that negatively affects living samples. This study demonstrates that much of the phototoxicity and photobleaching experienced with live-cell fluorescence imaging occurs as a result of 'illumination overhead' (IO). This occurs when a sample is illuminated but fluorescence emission is not being captured by the microscope camera. Several technological advancements have been developed, including fast-switching LED lamps and transistor-transistor logic (TTL) circuits, to diminish phototoxicity caused by IO. These advancements are not standard features on most microscopes and many biologists are unaware of their necessity for live-cell imaging. IO is particularly problematic when imaging rapid processes that require short exposure times. This study presents a workflow to optimize imaging conditions for measuring both slow and dynamic processes while minimizing phototoxicity on any standard microscope. The workflow includes a guide on how to (1) determine the maximum image exposure time for a dynamic process, (2) optimize excitation light intensity and (3) assess cell health with mitochondrial markers.This article has an associated First Person interview with the first author of the paper.
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Bioensaio , Luz , Microscopia de Fluorescência , Imagem Óptica , FotodegradaçãoRESUMO
Denitrification causes loss of available nitrogen from soil systems, thereby reducing crop productivity and increasing reliance on agrochemicals. The dynamics of denitrification and denitrifying communities are thought to be altered by land management practices, which affect the physicochemical properties of the soil. In this study, we look at the effects of long-term tillage and fertilization regimes on arable soils following 16 years of treatment in a factorial field trial. By studying the bacterial community composition based on 16S rRNA amplicons, absolute bacterial abundance and diversity of denitrification functional genes (nirK, nirS and nosZ), under conditions of minimum/conventional tillage and organic/synthetic mineral fertilizer, we tested how specific land management histories affect the diversity and distribution of both bacteria and denitrification genes. Bacterial and denitrifier communities were largely unaffected by land management history and clustered predominantly by spatial location, indicating that the variability in bacterial community composition in these arable soils is governed by innate environmental differences and Euclidean distance rather than agricultural management intervention.
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Microbiologia do Solo , Solo , Bactérias/genética , Desnitrificação , Fertilização , RNA Ribossômico 16S/genética , Areia , Solo/química , Reino UnidoRESUMO
SHC adaptor protein (SHCA) and lipoma-preferred partner (LPP) mediate transforming growth factor ß (TGFß)-induced breast cancer cell migration and invasion. Reduced expression of either protein diminishes breast cancer lung metastasis, but the reason for this effect is unclear. Here, using total internal reflection fluorescence (TIRF) microscopy, we found that TGFß enhanced the assembly and disassembly rates of paxillin-containing adhesions in an SHCA-dependent manner through the phosphorylation of the specific SHCA tyrosine residues Tyr-239, Tyr-240, and Tyr-313. Using a BioID proximity labeling approach, we show that SHCA exists in a complex with a variety of actin cytoskeletal proteins, including paxillin and LPP. Consistent with a functional interaction between SHCA and LPP, TGFß-induced LPP localization to cellular adhesions depended on SHCA. Once localized to the adhesions, LPP was required for TGFß-induced increases in cell migration and adhesion dynamics. Mutations that impaired LPP localization to adhesions (mLIM1) or impeded interactions with the actin cytoskeleton via α-actinin (ΔABD) abrogated migratory responses to TGFß. Live-cell TIRF microscopy revealed that SHCA clustering at the cell membrane preceded LPP recruitment. We therefore hypothesize that, in the presence of TGFß, SHCA promotes the formation of small, dynamic adhesions by acting as a nucleator of focal complex formation. Finally, we defined a previously unknown function for SHCA in the formation of invadopodia, a process that also required LPP. Our results reveal that SHCA controls the formation and function of adhesions and invadopodia, two key cellular structures required for breast cancer metastasis.
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Movimento Celular , Proteínas do Citoesqueleto/metabolismo , Proteínas com Domínio LIM/metabolismo , Podossomos/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Animais , Adesão Celular , Linhagem Celular Transformada , Proteínas do Citoesqueleto/genética , Feminino , Proteínas com Domínio LIM/genética , Camundongos , Paxilina/genética , Paxilina/metabolismo , Podossomos/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Fator de Crescimento Transformador betaRESUMO
A modern day light microscope has evolved from a tool devoted to making primarily empirical observations to what is now a sophisticated , quantitative device that is an integral part of both physical and life science research. Nowadays, microscopes are found in nearly every experimental laboratory. However, despite their prevalent use in capturing and quantifying scientific phenomena, neither a thorough understanding of the principles underlying quantitative imaging techniques nor appropriate knowledge of how to calibrate, operate and maintain microscopes can be taken for granted. This is clearly demonstrated by the well-documented and widespread difficulties that are routinely encountered in evaluating acquired data and reproducing scientific experiments. Indeed, studies have shown that more than 70% of researchers have tried and failed to repeat another scientist's experiments, while more than half have even failed to reproduce their own experiments. One factor behind the reproducibility crisis of experiments published in scientific journals is the frequent underreporting of imaging methods caused by a lack of awareness and/or a lack of knowledge of the applied technique. Whereas quality control procedures for some methods used in biomedical research, such as genomics (e.g. DNA sequencing, RNA-seq) or cytometry, have been introduced (e.g. ENCODE), this issue has not been tackled for optical microscopy instrumentation and images. Although many calibration standards and protocols have been published, there is a lack of awareness and agreement on common standards and guidelines for quality assessment and reproducibility. In April 2020, the QUality Assessment and REProducibility for instruments and images in Light Microscopy (QUAREP-LiMi) initiative was formed. This initiative comprises imaging scientists from academia and industry who share a common interest in achieving a better understanding of the performance and limitations of microscopes and improved quality control (QC) in light microscopy. The ultimate goal of the QUAREP-LiMi initiative is to establish a set of common QC standards, guidelines, metadata models and tools, including detailed protocols, with the ultimate aim of improving reproducible advances in scientific research. This White Paper (1) summarizes the major obstacles identified in the field that motivated the launch of the QUAREP-LiMi initiative; (2) identifies the urgent need to address these obstacles in a grassroots manner, through a community of stakeholders including, researchers, imaging scientists, bioimage analysts, bioimage informatics developers, corporate partners, funding agencies, standards organizations, scientific publishers and observers of such; (3) outlines the current actions of the QUAREP-LiMi initiative and (4) proposes future steps that can be taken to improve the dissemination and acceptance of the proposed guidelines to manage QC. To summarize, the principal goal of the QUAREP-LiMi initiative is to improve the overall quality and reproducibility of light microscope image data by introducing broadly accepted standard practices and accurately captured image data metrics.
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Microscopia , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
INTRODUCTION AND HYPOTHESIS: Symptomatic vaginal prolapse affects 6-28% of women and significantly impacts their quality of life. Pessaries for prolapse are used by three-quarters of clinicians as a first-line treatment; however, current clinical use in the UK is unknown and there is a lack of clinical guidance or training. This study is aimed at informing the upcoming UK Clinical Guidance on best practice for the use of pessaries document. METHODS: A 19-question, anonymised, electronic survey was sent to members of the nine professional bodies delivering pessary care in the UK. RESULTS: Of 917 respondents, 403 (246 nurses, 134 doctors, 22 physiotherapists and 1 other profession) currently deliver pessary care. PVC/vinyl ring, silicone ring, Gellhorn and shelf pessaries are most popular, and are used frequently by 93% of respondents. Further pessary training was deemed necessary by 62% of those currently providing pessary care, and 70% of those who do not. The most highly rated method for previous and future training is shadowing another clinician. One in three respondents receive no ancillary support and nearly 1 in 7 (predominantly nurses) report the absence of cross-cover arrangements, leaving a gap in care provision. CONCLUSIONS: Service provision, support and pessary training in the UK vary greatly. This calls for the standardisation of care, training and development of a national guideline. We present a clear rationale and need for a UK guideline on pessary management of vaginal prolapse and a standardised pessary training model for multi-professional use.
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Prolapso de Órgão Pélvico , Prolapso Uterino , Feminino , Humanos , Prolapso de Órgão Pélvico/terapia , Pessários , Qualidade de Vida , Inquéritos e Questionários , Reino Unido , Prolapso Uterino/terapiaRESUMO
BACKGROUND: The p66ShcA redox protein is the longest isoform of the Shc1 gene and is variably expressed in breast cancers. In response to a variety of stress stimuli, p66ShcA becomes phosphorylated on serine 36, which allows it to translocate from the cytoplasm to the mitochondria where it stimulates the formation of reactive oxygen species (ROS). Conflicting studies suggest both pro- and anti-tumorigenic functions for p66ShcA, which prompted us to examine the contribution of tumor cell-intrinsic functions of p66ShcA during breast cancer metastasis. METHODS: We tested whether p66ShcA impacts the lung-metastatic ability of breast cancer cells. Breast cancer cells characteristic of the ErbB2+/luminal (NIC) or basal (4T1) subtypes were engineered to overexpress p66ShcA. In addition, lung-metastatic 4T1 variants (4T1-537) were engineered to lack endogenous p66ShcA via Crispr/Cas9 genomic editing. p66ShcA null cells were then reconstituted with wild-type p66ShcA or a mutant (S36A) that cannot translocate to the mitochondria, thereby lacking the ability to stimulate mitochondrial-dependent ROS production. These cells were tested for their ability to form spontaneous metastases from the primary site or seed and colonize the lung in experimental (tail vein) metastasis assays. These cells were further characterized with respect to their migration rates, focal adhesion dynamics, and resistance to anoikis in vitro. Finally, their ability to survive in circulation and seed the lungs of mice was assessed in vivo. RESULTS: We show that p66ShcA increases the lung-metastatic potential of breast cancer cells by augmenting their ability to navigate each stage of the metastatic cascade. A non-phosphorylatable p66ShcA-S36A mutant, which cannot translocate to the mitochondria, still potentiated breast cancer cell migration, lung colonization, and growth of secondary lung metastases. However, breast cancer cell survival in the circulation uniquely required an intact p66ShcA S36 phosphorylation site. CONCLUSION: This study provides the first evidence that both mitochondrial and non-mitochondrial p66ShcA pools collaborate in breast cancer cells to promote their maximal metastatic fitness.