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1.
Trends Biotechnol ; 42(6): 739-759, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38310021

ABSTRACT

Organs-on-chips (OoCs) hold promise to engineer progressively more human-relevant in vitro models for pharmaceutical purposes. Recent developments have delivered increasingly sophisticated designs, yet OoCs still lack in reproducing the inner tissue physiology required to fully resemble the native human body. This review emphasizes the need to include microarchitectural and microstructural features, and discusses promising avenues to incorporate well-defined microarchitectures down to the single-cell level. We highlight how their integration will significantly contribute to the advancement of the field towards highly organized structural and hierarchical tissues-on-chip. We discuss the combination of state-of-the-art micropatterning technologies to achieve OoCs resembling human-intrinsic complexity. It is anticipated that these innovations will yield significant advances in realization of the next generation of OoC models.


Subject(s)
Bioprinting , Lab-On-A-Chip Devices , Tissue Engineering , Bioprinting/methods , Humans , Tissue Engineering/methods , Single-Cell Analysis/methods , Animals
2.
Viana do Castelo; s.n; 20231012.
Thesis in Portuguese | BDENF - Nursing | ID: biblio-1525823

ABSTRACT

Os cuidados paliativos abrangem intervenções no alívio do sofrimento da pessoa em situação paliativa e família. Para que se possam prestar cuidados paliativos de excelência é necessária uma equipa multiprofissional com competências específica e diferenciadas. Assim, os serviços de saúde estão a fazer uma aposta na formação contínua das suas equipas com o objetivo de contribuir para a qualidade desejada, o que traduzirá a sua idoneidade quer da atividade assistencial quer formativa. Partindo destes pressupostos, dando continuidade ao percurso académico, optou-se por realizar o Estágio de Natureza Profissional na Equipa Comunitária de Suporte em Cuidados Paliativos. O objetivo foi desenvolver competências especializadas na área da enfermagem à pessoa em situação paliativa. Durante o estágio, recorreu-se a metodologias ativas, participativas, investigativas, de gestão e formação. No domínio da investigação, desenvolveu-se um estudo exploratório descritivo sobre as necessidades de formação da equipa de saúde de Cuidados Paliativos, com o intuito de contribuir para a elaboração de um projeto de formação em serviço dando resposta a um dos requisitos de acreditação da idoneidade formativa. A recolha de dados realizou-se por meio de um questionário elaborado ad hoc e submetidos a análise estatística. Os principais resultados revelam que mais de metade da equipe de saúde multidisciplinar apresenta formação diferenciada em CP obtida através de cursos pós-graduação e mestrado. Apresenta carências de formação nas áreas de: Precauções Básicas de Controlo de Infeção, Gestão dos Riscos, Emergências Clínicas, Emergências Não Clínicas, e a equipa identifica necessidade de formação sobre Comunicação em Cuidados Paliativos e Apoios Sociais em Cuidados Paliativos, considera importante a formação contínua em serviço, reconhecendo vantagens, tais como atualização e consolidação de conhecimentos e, melhoria dos cuidados prestados além da aquisição. Apesar das dificuldades identificadas nomeadamente falta de tempo/disponibilidade, a falta de recursos humanos, falta de planeamento da formação infere-se a necessidade premente da existência de um projeto de formação contínua em contexto de prática clínica direcionada às reais necessidades enquanto motor de transformação no cuidar. No domínio da prestação de cuidados de enfermagem à pessoa em situação paliativa, foram desenvolvidas competências especializadas, designadamente ao nível da gestão de sintomas, apoio e acompanhamento à família, apoio no processo de luto, comunicação, trabalho em equipa e habilidades de consultadoria. Foram também adquiridas competências no que se refere à formação, à gestão de cuidados. Salienta-se que, é fundamental o desenvolvimento de competências especializadas em cuidados paliativos para a implementação de intervenções de enfermagem adequadas, efetivas e humanas no cuidar da pessoa em situação paliativa e família.


Palliative care encompasses interventions to relieve the suffering of the palliative care patient and family. In order to provide excellent palliative care, a multiprofessional team with specific and differentiated skills is required. Thus, health services are investing in the continuous training of their teams in order to contribute to the desired quality, which will reflect their suitability both in terms of care and training. Based on these assumptions, continuing the academic path, it was decided to carry out the Professional Internship in the Community Support Team in Palliative Care. The objective was to develop specialized skills in the area of nursing to the person in a palliative situation. During the internship, active, participatory, investigative, management and training methodologies were used. In the field of research, a descriptive exploratory study was developed on the training needs of the Palliative Care health team, with the aim of contributing to the elaboration of an in-service training plan in response to one of the requirements for accreditation of training suitability. Data were collected through an ad hoc questionnaire and submitted to statistical analysis. The main results show that more than half of the multidisciplinary health team has differentiated training in PC obtained through postgraduate and master's courses. It presents training deficiencies in the areas of: Basic Infection Control Precautions, Risk Management, Clinical Emergencies, Non-Clinical Emergencies, and the team identifies a need for training on Communication in Palliative Care and Social Supports in Palliative Care, considers continuous in-service training important, recognizing advantages such as updating and consolidating knowledge and, improving the care provided in addition to acquisition. Despite the difficulties identified, namely lack of time/availability, lack of human resources, lack of training planning, there is a pressing need for a continuous training plan in the context of clinical practice directed to real needs as a driver of transformation in care. In the field of providing nursing care to the person in a palliative situation, specialized skills were developed, namely in terms of symptom management, support and accompaniment to the family, support in the grieving process, communication, teamwork and consulting skills. Skills were also acquired in training, care management. It is emphasized that the development of specialized skills in palliative care is essential for the implementation of appropriate, effective and humane nursing interventions in the care of the person in a palliative situation and family.

3.
bioRxiv ; 2023 Aug 31.
Article in English | MEDLINE | ID: mdl-37693587

ABSTRACT

Previous observations showed that chloride and osmotic stress regulate the autophosphorylation and activity of the kinase domains of WNK1 and WNK3. Further, prior crystallography on the asymmetric dimeric of the unphosphorylated WNK1 kinase domain (WNK1/S382A, WNK1/SA) revealed conserved waters in the active site. Here we show by crystallography that PEG400 applied to crystals of dimeric WNK1/SA grown in space group P1 induces de-dimerization with a change in space group to P2 1 . Both the conserved waters, referred to here as conserved water network 1 (CWN1) and the chloride binding site are disrupted by PEG400. CWN1 is surrounded and stabilized by a pan-WNK-conserved cluster of charged residues. Here we mutagenized these charges in WNK3 to probe the importance of the CWN1 to WNK regulation. Two mutations at E314 in the Activation Loop (WNK3/E314Q and WNK3/E314A) enhanced activity, consistent with the idea that the CWN1 is inhibitory. Mutations of other residues in the cluster had similar or less activity than wild-type. PEG400 activation of WNK3 was not significantly reduced in the point mutants tested. The crystallographic and assay data support a role for CWN1 and the charged cluster in stabilizing an inactive configuration of WNKs and suggest that water functions as an allosteric inhibitor of WNKs.

4.
Mol Biol Cell ; 34(11): ar109, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37585288

ABSTRACT

Previous study has demonstrated that the WNK kinases 1 and 3 are direct osmosensors consistent with their established role in cell-volume control. WNK kinases may also be regulated by hydrostatic pressure. Hydrostatic pressure applied to cells in culture with N2 gas or to Drosophila Malpighian tubules by centrifugation induces phosphorylation of downstream effectors of endogenous WNKs. In vitro, the autophosphorylation and activity of the unphosphorylated kinase domain of WNK3 (uWNK3) is enhanced to a lesser extent than in cells by 190 kPa applied with N2 gas. Hydrostatic pressure measurably alters the structure of uWNK3. Data from size exclusion chromatography in line with multi-angle light scattering (SEC-MALS), SEC alone at different back pressures, analytical ultracentrifugation (AUC), NMR, and chemical crosslinking indicate a change in oligomeric structure in the presence of hydrostatic pressure from a WNK3 dimer to a monomer. The effects on the structure are related to those seen with osmolytes. Potential mechanisms of hydrostatic pressure activation of uWNK3 and the relationships of pressure activation to WNK osmosensing are discussed.


Subject(s)
Protein Serine-Threonine Kinases , Animals , Protein Serine-Threonine Kinases/metabolism , Hydrostatic Pressure , Phosphorylation
5.
Front Psychiatry ; 14: 1157710, 2023.
Article in English | MEDLINE | ID: mdl-37484671

ABSTRACT

The main purpose of this preliminary study was to investigate a potential relationship between early maladaptive schemas (EMSs) and impulsive and compulsive buying tendencies in a sample of young adults (college students). This research adds to the cognitive perspective of consumer behavior that the cognitive schemas putatively associated with early experiences may have a strong impact on impulsive and compulsive buying. Data was obtained from 365 participants in a cross-sectional study design. Participants completed an online survey with the following instruments: Young Schema Questionnaire; Impulsive Buying Tendency Measurement Scale; Richmond Compulsive Buying Scale; and Hospital Anxiety and Depression Scale. Using multiple linear hierarchical regressions, we confirmed that the domain of over vigilance and inhibition schemas was positively associated with impulsive and compulsive buying tendencies, while an opposite association was found for the domain of impaired limits. Being a female was also a predictor of impulsive buying and compulsive buying. The results were discussed in terms of the coping mechanisms to deal with negative emotions, as a way to obtain rewards, or as a way to escape painful self-awareness. Other mechanisms related to the internalization of perfectionist expectations and the propensity to shame were also explored.

6.
Biosens Bioelectron ; 237: 115510, 2023 Oct 01.
Article in English | MEDLINE | ID: mdl-37442028

ABSTRACT

Incorporating non-invasive biosensing features in organ-on-chip models is of paramount importance for a wider implementation of these advanced in vitro microfluidic platforms. Optical biosensors, based on Bioluminescence Imaging (BLI), enable continuous, non-invasive, and in-situ imaging of cells, tissues or miniaturized organs without the drawbacks of conventional fluorescence imaging. Here, we report the first-of-its-kind integration and optimization of BLI in microfluidic chips, for non-invasive imaging of multiple biological readouts. The cell line HEK293T-GFP was engineered to express NanoLuc® luciferase under the control of a constitutive promoter and were cultured on-chip in 3D, in standard ECM-like hydrogels, to assess optimal cell detection conditions. Using real-time in-vitro dual-color microscopy, Bioluminescence (BL) and fluorescence (FL) were detectable using distinct imaging setups. Detection of the bioluminescent signals were observed at single cell resolution on-chip 20 min post-addition of Furimazine substrate and under perfusion. All hydrogels enabled BLI with higher signal-to-noise ratios as compared to fluorescence. For instance, agarose gels showed a ∼5-fold greater BL signal over background after injection of the substrate as compared to the FL signal. The use of BLI with microfluidic chip technologies opens up the potential for simultaneous in situ detection with continuous monitoring of multicolor cell reporters. Moreover, this can be achieved in a non-invasive manner. BL has great promise as a highly desirable biosensor for studying organ-on-chip platforms.


Subject(s)
Biosensing Techniques , Humans , HEK293 Cells , Biosensing Techniques/methods , Microfluidics , Microscopy , Optical Imaging
7.
Front Hum Neurosci ; 16: 971315, 2022.
Article in English | MEDLINE | ID: mdl-35992948

ABSTRACT

Background: With the emergence of Brain Computer Interfaces (BCI), clinicians have been facing a new group of patients with severe acquired brain injury who are unable to show any behavioral sign of consciousness but respond to active neuroimaging or electrophysiological paradigms. However, even though well documented, there is still no consensus regarding the nomenclature for this clinical entity. Objectives: This systematic review aims to 1) identify the terms used to indicate the presence of this entity through the years, and 2) promote an informed discussion regarding the rationale for these names and the best candidates to name this fascinating disorder. Methods: The Disorders of Consciousness Special Interest Group (DoC SIG) of the International Brain Injury Association (IBIA) launched a search on Pubmed and Google scholar following PRISMA guidelines to collect peer-reviewed articles and reviews on human adults (>18 years) published in English between 2006 and 2021. Results: The search launched in January 2021 identified 4,089 potentially relevant titles. After screening, 1,126 abstracts were found relevant. Finally, 161 manuscripts were included in our analyses. Only 58% of the manuscripts used a specific name to discuss this clinical entity, among which 32% used several names interchangeably throughout the text. We found 25 different names given to this entity. The five following names were the ones the most frequently used: covert awareness, cognitive motor dissociation, functional locked-in, non-behavioral MCS (MCS*) and higher-order cortex motor dissociation. Conclusion: Since 2006, there has been no agreement regarding the taxonomy to use for unresponsive patients who are able to respond to active neuroimaging or electrophysiological paradigms. Developing a standard taxonomy is an important goal for future research studies and clinical translation. We recommend a Delphi study in order to build such a consensus.

8.
Chemistry ; 28(66): e202202333, 2022 Nov 25.
Article in English | MEDLINE | ID: mdl-36037397

ABSTRACT

Electron harvesting bacteria are key targets to develop microbial electrosynthesis technologies, which are valid alternatives for the production of value-added compounds without utilization of fossil fuels. Geobacter sulfurreducens, that is capable of donating and accepting electrons from electrodes, is one of the most promising electroactive bacteria. Its electron transfer mechanisms to electrodes have been progressively elucidated, however the electron harvesting pathways are still poorly understood. Previous studies showed that the periplasmic cytochromes PccH and GSU2515 are overexpressed in current-consuming G. sulfurreducens biofilms. PccH was characterized, though no putative partners have been identified. In this work, GSU2515 was characterized by complementary biophysical techniques and in silico simulations using the AlphaFold neural network. GSU2515 is a low-spin monoheme cytochrome with a disordered N-terminal region and an α-helical C-terminal domain harboring the heme group. The cytochrome undergoes a redox-linked heme axial ligand switch, with Met91 and His94 as distal axial ligands in the reduced and oxidized states, respectively. The reduction potential of the cytochrome is negative and modulated by the pH in the physiological range: -78 mV at pH 6 and -113 mV at pH 7. Such pH-dependence coupled to the redox-linked switch of the axial ligand allows the cytochrome to drive a proton-coupled electron transfer step that is crucial to confer directionality to the respiratory chain. Biomolecular interactions and electron transfer experiments indicated that GSU2515 and PccH form a redox complex. Overall, the data obtained highlight for the first time how periplasmic proteins bridge the electron transfer between the outer and inner membrane in the electron harvesting pathways of G. sulfurreducens.


Subject(s)
Bacterial Proteins , Electrons , Ligands , Bacterial Proteins/metabolism , Cytochromes/chemistry , Cytochromes/metabolism , Heme/chemistry , Electron Transport , Oxidation-Reduction
9.
Adv Exp Med Biol ; 1379: 171-203, 2022.
Article in English | MEDLINE | ID: mdl-35760992

ABSTRACT

Organs-on-chips are microfluidic tissue-engineered models that offer unprecedented dynamic control over cellular microenvironments, emulating key functional features of organs or tissues. Sensing technologies are increasingly becoming an essential part of such advanced model systems for real-time detection of cellular behavior and systemic-like events. The fast-developing field of organs-on-chips is accelerating the development of biosensors toward easier integration, thus smaller and less invasive, leading to enhanced access and detection of (patho-) physiological biomarkers. The outstanding combination of organs-on-chips and biosensors holds the promise to contribute to more effective treatments, and, importantly, improve the ability to detect and monitor several diseases at an earlier stage, which is particularly relevant for complex diseases such as cancer. Biosensors coupled with organs-on-chips are currently being devised not only to determine therapy effectiveness but also to identify emerging cancer biomarkers and targets. The ever-expanding use of imaging modalities for optical biosensors oriented toward on-chip applications is leading to less intrusive and more reliable detection of events both at the cellular and microenvironment levels. This chapter comprises an overview of hybrid approaches combining organs-on-chips and biosensors, focused on modeling and investigating solid tumors, and, in particular, the tumor microenvironment. Optical imaging modalities, specifically fluorescence and bioluminescence, will be also described, addressing the current limitations and future directions toward an even more seamless integration of these advanced technologies.


Subject(s)
Biosensing Techniques , Neoplasms , Cellular Microenvironment , Humans , Microfluidics/methods , Neoplasms/diagnosis , Tissue Engineering/methods , Tumor Microenvironment
10.
ACS Biomater Sci Eng ; 8(6): 2684-2699, 2022 06 13.
Article in English | MEDLINE | ID: mdl-35502997

ABSTRACT

A comparatively straightforward approach to accomplish more physiological realism in organ-on-a-chip (OoC) models is through substrate geometry. There is increasing evidence that the strongly, microscale curved surfaces that epithelial or endothelial cells experience when lining small body lumens, such as the alveoli or blood vessels, impact their behavior. However, the most commonly used cell culture substrates for modeling of these human tissue barriers in OoCs, ion track-etched porous membranes, provide only flat surfaces. Here, we propose a more realistic culture environment for alveolar cells based on biomimetically microcurved track-etched membranes. They recreate the mainly spherical geometry of the cells' native microenvironment. In this feasibility study, the membranes were given the shape of hexagonally arrayed hemispherical microwells by an innovative combination of three-dimensional (3D) microfilm (thermo)forming and ion track technology. Integrated in microfluidic chips, they separated a top from a bottom cell culture chamber. The microcurved membranes were seeded by infusion with primary human alveolar epithelial cells. Despite the pronounced topology, the cells fully lined the alveoli-like microwell structures on the membranes' top side. The confluent curved epithelial cell monolayers could be cultured successfully at the air-liquid interface for 14 days. Similarly, the top and bottom sides of the microcurved membranes were seeded with cells from the Calu-3 lung epithelial cell line and human lung microvascular endothelial cells, respectively. Thereby, the latter lined the interalveolar septum-like interspace between the microwells in a network-type fashion, as in the natural counterpart. The coculture was maintained for 11 days. The presented 3D lung-on-a-chip model might set the stage for other (micro)anatomically inspired membrane-based OoCs in the future.


Subject(s)
Endothelial Cells , Lung , Cell Culture Techniques/methods , Epithelial Cells , Humans , Lung/physiology , Microfluidics/methods
11.
Nat Rev Rheumatol ; 18(4): 217-231, 2022 04.
Article in English | MEDLINE | ID: mdl-35058618

ABSTRACT

Arthritis affects millions of people worldwide. With only a few disease-modifying drugs available for treatment of rheumatoid arthritis and none for osteoarthritis, a clear need exists for new treatment options. Current disease models used for drug screening and development suffer from several disadvantages and, most importantly, do not accurately emulate all facets of human joint diseases. A humanized joint-on-chip (JoC) model or platform could revolutionize research and drug development in rheumatic diseases. A JoC model is a multi-organ-on-chip platform that incorporates a range of engineered features to emulate essential aspects and functions of the human joint and faithfully recapitulates the joint's physiological responses. In this Review, we propose an architecture for such a JoC platform, discuss the status of the engineering of individual joint tissues and the efforts to combine them in a functional JoC model and identify unresolved issues and challenges in constructing an accurate, physiologically relevant system. The goal is to ultimately obtain a reliable and ready-to-use humanized model of the joint for studying the pathophysiology of rheumatic diseases and screening drugs for treatment of these conditions.


Subject(s)
Arthritis, Rheumatoid , Osteoarthritis , Arthritis, Rheumatoid/drug therapy , Bone and Bones , Humans
12.
Cells Tissues Organs ; 211(6): 721-735, 2022.
Article in English | MEDLINE | ID: mdl-34198305

ABSTRACT

The development of new therapies is tremendously hampered by the insufficient availability of human model systems suitable for preclinical research on disease target identification, drug efficacy, and toxicity. Thus, drug failures in clinical trials are too common and too costly. Animal models or standard 2D in vitro tissue cultures, regardless of whether they are human based, are regularly not representative of specific human responses. Approaching near human tissues and organs test systems is the key goal of organs-on-chips (OoC) technology. This technology is currently showing its potential to reduce both drug development costs and time-to-market, while critically lessening animal testing. OoC are based on human (stem) cells, potentially derived from healthy or disease-affected patients, thereby amenable to personalized therapy development. It is noteworthy that the OoC market potential goes beyond pharma, with the possibility to test cosmetics, food additives, or environmental contaminants. This (micro)tissue engineering-based technology is highly multidisciplinary, combining fields such as (developmental) biology, (bio)materials, microfluidics, sensors, and imaging. The enormous potential of OoC is currently facing an exciting new challenge: emulating cross-communication between tissues and organs, to simulate more complex systemic responses, such as in cancer, or restricted to confined environments, as occurs in osteoarthritis. This review describes key examples of multiorgan/tissue-on-chip approaches, or linked organs/tissues-on-chip, focusing on challenges and promising new avenues of this advanced model system. Additionally, major emphasis is given to the translation of established tissue engineering approaches, bottom up and top down, towards the development of more complex, robust, and representative (multi)organ/tissue-on-chip approaches.


Subject(s)
Lab-On-A-Chip Devices , Tissue Engineering , Animals , Humans , Tissue Engineering/methods , Drug Development , Stem Cells , Microfluidics
13.
Adv Funct Mater ; 31(42)2021 Oct 14.
Article in English | MEDLINE | ID: mdl-34924912

ABSTRACT

Bioengineering of tissues and organs has the potential to generate functional replacement organs. However, achieving the full-thickness vascularization that is required for long-term survival of living implants has remained a grand challenge, especially for clinically sized implants. During the pre-vascular phase, implanted engineered tissues are forced to metabolically rely on the diffusion of nutrients from adjacent host-tissue, which for larger living implants results in anoxia, cell death, and ultimately implant failure. Here it is reported that this challenge can be addressed by engineering self-oxygenating tissues, which is achieved via the incorporation of hydrophobic oxygen-generating micromaterials into engineered tissues. Self-oxygenation of tissues transforms anoxic stresses into hypoxic stimulation in a homogenous and tissue size-independent manner. The in situ elevation of oxygen tension enables the sustained production of high quantities of angiogenic factors by implanted cells, which are offered a metabolically protected pro-angiogenic microenvironment. Numerical simulations predict that self-oxygenation of living tissues will effectively orchestrate rapid full-thickness vascularization of implanted tissues, which is empirically confirmed via in vivo experimentation. Self-oxygenation of tissues thus represents a novel, effective, and widely applicable strategy to enable the vascularization living implants, which is expected to advance organ transplantation and regenerative medicine applications.

14.
Front Hum Neurosci ; 15: 728637, 2021.
Article in English | MEDLINE | ID: mdl-34924975

ABSTRACT

Purpose: The recommended way to assess consciousness in prolonged disorders of consciousness is to observe the patient's responses to sensory stimulation. Multiple assessment sessions have to be completed in order to reach a correct diagnosis. There is, however, a lack of data on how many sessions are sufficient for validity and reliability. The aim of this study was to identify the number of Sensory Modality Assessment and Rehabilitation Technique (SMART) assessment sessions needed to reach a reliable diagnosis. A secondary objective was to identify which sensory stimulation modalities are more useful to reach a diagnosis. Materials and Methods: A retrospective analysis of all the adult patients (who received a SMART assessment) admitted to a specialist brain injury unit over the course of 4 years was conducted (n = 35). An independent rater analyzed the SMART levels for each modality and session and provided a suggestive diagnosis based on the highest SMART level per session. Results: For the vast majority of patients between 5 and 6 sessions was sufficient to reach the final clinical diagnosis. The visual, auditory, tactile, and motor function modalities were found to be more associated with the final diagnosis than the olfactory and gustatory modalities. Conclusion: These findings provide for the first time a rationale for optimizing the time spent on assessing patients using SMART.

15.
J Biol Chem ; 296: 100711, 2021.
Article in English | MEDLINE | ID: mdl-33915126

ABSTRACT

Geobacter bacteria are able to transfer electrons to the exterior of the cell and reduce extracellular electron acceptors including toxic/radioactive metals and electrode surfaces, with potential applications in bioremediation or electricity harvesting. The triheme c-type cytochrome PpcA from Geobacter metallireducens plays a crucial role in bridging the electron transfer from the inner to the outer membrane, ensuring an effective extracellular electron transfer. This cytochrome shares 80% identity with PpcA from Geobacter sulfurreducens, but their redox properties are markedly different, thus determining the distinctive working redox potential ranges in the two bacteria. PpcA from G. metallireducens possesses two extra aromatic amino acids (Phe-6 and Trp-45) in its hydrophobic heme core, whereas PpcA from G. sulfurreducens has a leucine and a methionine in the equivalent positions. Given the different nature of these residues in the two cytochromes, we have hypothesized that the extra aromatic amino acids could be partially responsible for the observed functional differences. In this work, we have replaced Phe-6 and Trp-45 residues by their nonaromatic counterparts in PpcA from G. sulfurreducens. Using redox titrations followed by UV-visible and NMR spectroscopy we observed that residue Trp-45 shifted the redox potential range 33% toward that of PpcA from G. sulfurreducens, whereas Phe-6 produced a negligible effect. For the first time, it is shown that the inclusion of an aromatic residue at the heme core can modulate the working redox range in abundant periplasmic proteins, paving the way to engineer bacterial strains for optimal microbial bioelectrochemical applications.


Subject(s)
Cytochromes/chemistry , Cytochromes/metabolism , Geobacter/cytology , Geobacter/enzymology , Heme , Periplasm/enzymology , Hydrophobic and Hydrophilic Interactions , Kinetics , Models, Molecular , Oxidation-Reduction , Protein Domains
16.
J Rehabil Med ; 53(5): jrm00193, 2021 05 18.
Article in English | MEDLINE | ID: mdl-33871035

ABSTRACT

The number of patients surviving severe brain injury is increasing; however, many are left in a prolonged disorder of consciousness. With appropriate treatment, patients with prolonged disorders of consciousness can survive for years. Unless an advance directive exists, the treating clinicians can authorize withdrawal of clinically assisted nutrition and hydration for these patients, based on best interests. The classic terminology used in prolonged disorders of consciousness ranges from coma, vegetative state to minimally conscious state. However, a new group of patients with covert cognition has been identified in the last decade, making it necessary to revise the current taxonomy to better reflect our understanding of these conditions. With the introduction of a less ambiguous terminology, the challenges when it comes to withdrawal of clinically assisted nutrition and hydration of these patients may ease. A decision-making pathway for withdrawal of clinically assisted nutrition and hydration for patients with prolonged disorders of consciousness, based on a new taxonomy is proposed. These decisions should be based primarily on best interests. The adoption of a new classification for impairments of consciousness would clarify and improve how we think about these patients. Moreover, the development of accurate prognostic predictors would be a major step in the decision-making process, as it would influence the beneficent pathway towards the best clinical outcome.


Subject(s)
Classification/methods , Consciousness Disorders/therapy , Decision Making/physiology , Nutrition Assessment , Female , Humans , Male
17.
Trends Cancer ; 7(3): 249-264, 2021 03.
Article in English | MEDLINE | ID: mdl-33218948

ABSTRACT

The complex microenvironment in which malignant tumor cells grow is crucial for cancer progression. The physical and biochemical characteristics of this niche are involved in controlling cancer cell differentiation, proliferation, invasion, and metastasis. It is therefore essential to understand how cancer cells interact and communicate with their surrounding tissue - the so-called tumor stroma - and how this interplay regulates disease progression. To mimic the tumor microenvironment (TME), 3D in vitro models are widely used because they can incorporate different patient-derived tissues/cells and allow longitudinal readouts, thus permitting deeper understanding of cell interactions. These models are therefore excellent tools to bridge the gap between oversimplified 2D systems and unrepresentative animal models. We present an overview of state-of-the-art 3D models for studying tumor-stroma interactions, with a focus on understanding why the TME is a key target in cancer therapy.


Subject(s)
Cell Communication , Cell Culture Techniques/methods , Neoplasms/pathology , Tumor Microenvironment , Animals , Bioprinting , Cell Differentiation , Cell Line, Tumor , Cell Movement , Cell Proliferation , Disease Progression , Extracellular Matrix , Humans , Organoids , Printing, Three-Dimensional , Stromal Cells/pathology
18.
Polymers (Basel) ; 14(1)2021 Dec 22.
Article in English | MEDLINE | ID: mdl-35012056

ABSTRACT

This prospective, double-blind, six-arm parallel randomised controlled trial aimed to compare the performance of two universal adhesives (UAs) in non-carious cervical lesions (NCCLs), using the FDI criteria, and analysed if participants/NCCLs' characteristics influenced the outcome. Thirty-eight 18- to 65-year-old participants were seeking routine dental care at a university clinic. At baseline, 210 NCCLs were randomly allocated to six groups (35 restorations' each). The UAs tested were FuturabondU (FBU) and AdheseUniversal (ADU) applied in either etch-and-rinse (ER) and self-etch (SE) modes. FuturabondDC (FBDC) in SE and in SE with selective enamel etching (SE-EE) modes were controls. NCCLs were restored with AdmiraFusion. The analysis included nonparametric tests, Kaplan-Meier and log-rank tests (α = 0.05). At 2-years, of 191 restorations, ten were missed due to retention loss (all groups, p > 0.05). FBDC (p = 0.037) and FBU (p = 0.041) performed worse than ADU in SE mode. FBDC and FBU also showed worse functional success rate (p = 0.012, p = 0.007, respectively) and cumulative retention rates (p = 0.022, p = 0.012, respectively) than ADU. Some participants/NCCLs' characteristics influenced (p < 0.05) the outcomes. FBU did not perform as well as ADU, especially in SE mode and due to functional properties. Participants' age and NCCLs' degree of dentin sclerosis and internal shape angle influenced FBU performance.

20.
Nat Biomed Eng ; 4(4): 394-406, 2020 04.
Article in English | MEDLINE | ID: mdl-31988457

ABSTRACT

The inaccessibility of living bone marrow (BM) hampers the study of its pathophysiology under myelotoxic stress induced by drugs, radiation or genetic mutations. Here, we show that a vascularized human BM-on-a-chip (BM chip) supports the differentiation and maturation of multiple blood cell lineages over 4 weeks while improving CD34+ cell maintenance, and that it recapitulates aspects of BM injury, including myeloerythroid toxicity after clinically relevant exposures to chemotherapeutic drugs and ionizing radiation, as well as BM recovery after drug-induced myelosuppression. The chip comprises a fluidic channel filled with a fibrin gel in which CD34+ cells and BM-derived stromal cells are co-cultured, a parallel channel lined by human vascular endothelium and perfused with culture medium, and a porous membrane separating the two channels. We also show that BM chips containing cells from patients with the rare genetic disorder Shwachman-Diamond syndrome reproduced key haematopoietic defects and led to the discovery of a neutrophil maturation abnormality. As an in vitro model of haematopoietic dysfunction, the BM chip may serve as a human-specific alternative to animal testing for the study of BM pathophysiology.


Subject(s)
Bone Marrow Cells/cytology , Bone Marrow/pathology , Hematopoiesis , Microfluidics/methods , Animals , Antigens, CD34 , Bone Marrow/drug effects , Bone Marrow/radiation effects , Bone Marrow Transplantation , Cell Differentiation , Cell Proliferation , Cells, Cultured , Humans , Lab-On-A-Chip Devices , Mesenchymal Stem Cells , Microfluidics/instrumentation
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