Resgatando o cuidado num terreno tóxico Lancellotti, Helena Patini; Fonseca, Claudia Lee Williams
Anuário antropológico,
04/2023, Letnik:
48, Številka:
1
Journal Article
Recenzirano
Odprti dostop
A partir de uma etnografia realizada entre usuários de tornozeleiras no sistema de monitoramento eletrônico no Sul do Brasil, exploramos a noção da “infraestrutura do cuidado” para entender por que, ...em certos casos, o dispositivo não parece alcançar os objetivos projetados nem do sistema judiciário nem dos apenados. Nossa análise inspira-se no trabalho de Maria Puig de la Bellacasa, que encoraja pesquisadores a resgatar a noção de cuidado das garras de perspectivas idealizadas – isto é, de visões normativas descrevendo um trabalho abnegado por cuidadores perfeitos. No intuito de restituir seu pleno potencial político, abraçamos uma abordagem não inocente da noção de cuidado que adentra os terrenos tóxicos das dinâmicas de poder e exclusão. Olhando em particular para a organização das atividades domésticas, atentamo-nos para os atos e atores normalmente invisibilizados dos presos em regime do semiaberto. Perguntamos quais as práticas que facilitam ou, pelo contrário, travam as engrenagens do sistema que rege a vida desses usuários de tornozeleiras. Com isso, esperamos realizar três objetivos: sublinhar o caráter coletivo da estrutura do cuidado, aumentar a visibilidade de coisas e pessoas previamente negligenciadas, e finalmente acrescentar densidade à nossa apreensão das consequências reais de certo artefato tecnológico para o universo heterogêneo de apenados.
One approach to improve the utility of adeno-associated virus (AAV)-based gene therapy is to engineer the AAV capsid to (i) overcome poor transport through tissue barriers and (ii) redirect the ...broadly tropic AAV to disease-relevant cell types. Peptide- or protein-domain insertions into AAV surface loops can achieve both engineering goals by introducing a new interaction surface on the AAV capsid. However, we understand little about the impact of insertions on capsid structure and the extent to which engineered inserts depend on a specific capsid context to function. Here, we examine insert-capsid interactions for the engineered variant AAV9-PHP.B. The 7-amino-acid peptide insert in AAV9-PHP.B facilitates transport across the murine blood-brain barrier via binding to the receptor Ly6a. When transferred to AAV1, the engineered peptide does not bind Ly6a. Comparative structural analysis of AAV1-PHP.B and AAV9-PHP.B revealed that the inserted 7-amino-acid loop is highly flexible and has remarkably little impact on the surrounding capsid conformation. Our work demonstrates that Ly6a binding requires interactions with both the PHP.B peptide and specific residues from the AAV9 HVR VIII region. An AAV1-based vector that incorporates a larger region of AAV9-PHP.B-including the 7-amino-acid loop and adjacent HVR VIII amino acids-can bind to Ly6a and localize to brain tissue. However, unlike AAV9-PHP.B, this AAV1-based vector does not penetrate the blood-brain barrier. Here we discuss the implications for AAV capsid engineering and the transfer of engineered activities between serotypes.
Targeting AAV vectors to specific cellular receptors is a promising strategy for enhancing expression in target cells or tissues while reducing off-target transgene expression. The AAV9-PHP.B/Ly6a interaction provides a model system with a robust biological readout that can be interrogated to better understand the biology of AAV vectors' interactions with target receptors. In this work, we analyzed the sequence and structural features required to successfully transfer the Ly6a receptor-binding epitope from AAV9-PHP.B to another capsid of clinical interest, AAV1. We found that AAV1- and AAV9-based vectors targeted to the same receptor exhibited different brain-transduction profiles. Our work suggests that, in addition to attachment-receptor binding, the capsid context in which this binding occurs is important for a vector's performance.
Vestibular Implant Surgery Schoo, Desi P.; Ward, Bryan K.; Chow, Margaret R. ...
The Laryngoscope,
April 2024, Letnik:
134, Številka:
4
Journal Article
Abstract The growing scale and dimensionality of multiplexed imaging require reproducible and comprehensive yet user-friendly computational pipelines. TRACERx-PHLEX performs deep learning-based cell ...segmentation (deep-imcyto), automated cell-type annotation (TYPEx) and interpretable spatial analysis (Spatial-PHLEX) as three independent but interoperable modules. PHLEX generates single-cell identities, cell densities within tissue compartments, marker positivity calls and spatial metrics such as cellular barrier scores, along with summary graphs and spatial visualisations. PHLEX was developed using imaging mass cytometry (IMC) in the TRACERx study, validated using published Co-detection by indexing (CODEX), IMC and orthogonal data and benchmarked against state-of-the-art approaches. We evaluated its use on different tissue types, tissue fixation conditions, image sizes and antibody panels. As PHLEX is an automated and containerised Nextflow pipeline, manual assessment, programming skills or pathology expertise are not essential. PHLEX offers an end-to-end solution in a growing field of highly multiplexed data and provides clinically relevant insights.
Background The aim of this study was to improve fluorescence laparoscopy of pancreatic cancer in an orthotopic mouse model with the use of a light-emitting diode (LED) light source and optimal ...fluorophore combinations. Study Design Human pancreatic cancer models were established with fluorescent FG-RFP, MiaPaca2-GFP, BxPC-3-RFP, and BxPC-3 cancer cells implanted in 6-week-old female athymic mice. Two weeks postimplantation, diagnostic laparoscopy was performed with a Stryker L9000 LED light source or a Stryker X8000 xenon light source 24 hours after tail-vein injection of CEA antibodies conjugated with Alexa 488 or Alexa 555. Cancer lesions were detected and localized under each light mode. Intravital images were also obtained with the OV-100 Olympus and Maestro CRI Small Animal Imaging Systems, serving as a positive control. Tumors were collected for histologic analysis. Results Fluorescence laparoscopy with a 495-nm emission filter and an LED light source enabled real-time visualization of the fluorescence-labeled tumor deposits in the peritoneal cavity. The simultaneous use of different fluorophores (Alexa 488 and Alexa 555), conjugated to antibodies, brightened the fluorescence signal, enhancing detection of submillimeter lesions without compromising background illumination. Adjustments to the LED light source permitted simultaneous detection of tumor lesions of different fluorescent colors and surrounding structures with minimal autofluorescence. Conclusions Using an LED light source with adjustments to the red, blue, and green wavelengths, it is possible to simultaneously identify tumor metastases expressing fluorescent proteins of different wavelengths, which greatly enhanced the signal without compromising background illumination. Development of this fluorescence laparoscopy technology for clinical use can improve staging and resection of pancreatic cancer.
The cytosolic iron–sulfur cluster assembly (CIA) system assembles iron–sulfur (FeS) cluster cofactors and inserts them into >20 apoprotein targets residing in the cytosol and nucleus. Three CIA ...proteins, called Cia1, Cia2, and Met18 in yeast, form the targeting complex responsible for apo-target recognition. There is little information about the structure of this complex or its mechanism of CIA substrate recognition. Herein, we exploit affinity co-purification and size exclusion chromatography to determine the subunit connectivity and stoichiometry of the CIA targeting complex. We conclude that Cia2 is the organizing center of the targeting complex, which contains one Met18, two Cia1, and four Cia2 polypeptides. To probe target recognition specificity, we utilize the CIA substrates Leu1 and Rad3 as well as the Escherichia coli FeS-binding transcription factor FNR (fumerate nitrate reductase). We demonstrate that both of the yeast CIA substrates are recognized, whereas the bacterial protein is not. Thus, while the targeting complex exhibits flexible target recognition in vitro, it cannot promiscuously recognize any FeS protein. Additionally, we demonstrate that the full CIA targeting complex is required to stably bind Leu1 in vitro, whereas the Met18–Cia2 subcomplex is sufficient to recognize Rad3. Together, these results allow us to propose a unifying model for the architecture of this highly conserved complex and demonstrate what component or subcomplexes are vital for target identification.
The vascular endothelium is the innermost layer of blood vessels and is a key regulator of vascular tone. Endothelial function is controlled by receptor signaling through G protein-coupled receptors, ...receptor tyrosine kinases and receptor serine-threonine kinases. The β-arrestins, multifunctional adapter proteins, have the potential to regulate all of these receptor families, although it is unclear as to whether they serve to integrate signaling across all of these different axes. Notably, the β-arrestins have been shown to regulate signaling by a number of receptors important in endothelial function, such as chemokine receptors and receptors for vasoactive substances such as angiotensin II, endothelin-1 and prostaglandins. β-arrestin-mediated signaling pathways have been shown to play central roles in pathways that control vasodilation, cell proliferation, migration, and immune function. At this time, the physiological impact of this signaling has not been studied in detail, but a deeper understanding of it could lead to the development of novel therapies for the treatment of vascular disease.
PDF
