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1.
BMC Prim Care ; 25(1): 217, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38879532

RESUMEN

BACKGROUND: Advance care planning (ACP) is a process which enables patients to communicate wishes, values, fears, and preferences for future medical care. Despite patient interest in ACP, the frequency of discussions remains low. Barriers to ACP may be mitigated by involving non-physician clinic staff, preparing patients ahead of visits, and using tools to structure visits. An ACP care pathway incorporating these principles was implemented in longitudinal generalist outpatient care, including primary care/family medicine and general internal medicine, in two Canadian provinces. This study aims to understand clinician experiences implementing the pathway. METHODS: The pathway was implemented in one family practice in Alberta, two family practices in British Columbia (BC), and one BC internal medicine outpatient clinic. Physicians and allied health professionals delivered structured pathway visits based on the Serious Illness Conversation Guide. Twelve physicians and one social worker participated in interviews or focus groups at the end of the study period. Qualitative data were coded inductively using an iterative approach, with regular meetings between coders. RESULTS: Clinicians described experiences with the ACP care pathway, impact at the clinician level, and impact at the patient level. Within each domain, clinicians described barriers and facilitators experienced during implementation. Clinicians also reflected candidly about potential for future implementation and the sustainability of the pathway. CONCLUSIONS: While the pathway was implemented slightly differently between provinces, core experiences were that implementation of the pathway, and integration with current practice, were feasible. Across settings, similar themes recurred regarding usefulness of the pathway structure and its tools, impact on clinician confidence and interactions with patients, teamwork and task delegation, compatibility with existing workflow, and patient preparation and readiness. Clinicians were supportive of ACP and of the pathway. TRIAL REGISTRATION: The study was prospectively registered with clinicaltrials.gov (NCT03508557). Registered April 25, 2018. https://classic. CLINICALTRIALS: gov/ct2/show/NCT03508557 .


Asunto(s)
Planificación Anticipada de Atención , Investigación Cualitativa , Humanos , Colombia Británica , Alberta , Masculino , Femenino , Actitud del Personal de Salud , Grupos Focales , Medicina Familiar y Comunitaria/organización & administración , Persona de Mediana Edad , Adulto , Vías Clínicas/organización & administración
2.
ACS Appl Mater Interfaces ; 16(27): 34830-34839, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38941578

RESUMEN

Li-ion battery degradation and safety events are often attributed to undesirable metallic lithium plating. Since their release, Li-ion battery electrodes have been made progressively thicker to provide a higher energy density. However, the propensity for plating in these thicker pairings is not well understood. Herein, we combine an experimental plating-prone condition with robust mesoscale modeling to examine electrode pairings with capacities ranging from 2.5 to 6 mAh/cm2 and negative to positive (N/P) electrode areal capacity ratio from 0.9 to 1.8 without the need for extensive aging tests. Using both experimentation and a mesoscale model, we identify a shift from conventional high state-of-charge (SOC) type plating to high overpotential (OP) type plating as electrode thickness increases. These two plating modes have distinct morphologies, identified by optical microscopy and electrochemical signatures. We demonstrate that under operating conditions where these plating modes converge, a high propensity of plating exists, revealing the importance of predicting and avoiding this overlap for a given electrode pairing. Further, we identify that thicker electrodes, beyond a capacity of 3 mAh/cm2 or thickness >75 µm, are prone to high OP, limiting negative electrode (NE) utilization and preventing cross-sectional oversizing the NE from mitigating plating. Here, it simply contributes to added mass and volume. The experimental thermal gradient and mesoscale model either combined or independently provide techniques capable of probing performance and safety implications of mild changes to electrode design features.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38626990

RESUMEN

OBJECTIVES: This study examines trends in advance care planning (ACP) awareness, engagement, attitude and experiences among the public in British Columbia (BC), Canada, from 2012 to 2020. This time period is of relevance as it includes provincial education initiatives. We also explored demographic characteristics associated with lower ACP awareness and engagement, to inform future initiatives. METHODS: Longitudinal data from two provincial polls in 2016 and 2020, along with BC-specific data extracted from a national poll in 2012, were analysed to investigate ACP awareness, engagement and attitudes. Demographic characteristics associated with ACP were examined using binomial and ordinal logistic regression. RESULTS: We observed an increase in awareness of ACP between 2012 and 2020 (from 15.2% to 32.9%). A significant rise in engagement was also observed, with more respondents reporting ACP conversations with healthcare providers between 2016 and 2020 (8.8%-14%) and documenting their healthcare wishes since 2012 (11.6%-28.0%). Demographic analysis revealed that older, female and more educated individuals were more likely to participate in ACP activities. CONCLUSIONS: This study highlights positive trends in ACP awareness and engagement in BC over the study period. Despite lower rates in some variables, the observed increases suggest increasing awareness over time, with potential for further improvement. However, disparities persist among different demographic groups, highlighting the need for targeted efforts to improve ACP knowledge and participation, especially among younger adults, males, single individuals and those with lower education levels.

4.
Ann Allergy Asthma Immunol ; 132(2): 223-228.e8, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37871771

RESUMEN

BACKGROUND: Cost-related nonadherence to medications can be a barrier to asthma management. OBJECTIVE: To quantify the impact of public drug plan deductibles on adherence to asthma medications. METHODS: We used a quasi-experimental regression discontinuity analysis to determine whether thresholds in deductibles for public drug coverage, determined on the basis of annual household income, decreased medication use among lower-income children and adults with asthma in British Columbia from 2013 to 2018. Using dispensed medication records, we evaluated deductible thresholds at annual household incomes of $15,000 (a deductible increase from 0% to 2% of annual household income), and $30,000 (a deductible increase from 2% to 3% annual household income). We evaluated medication costs, use, the ratio of inhaled corticosteroids-containing controller medications to total medications, excessive use of short-acting ß-agonists, and the proportion of days covered by controller therapies. All costs are reported in 2020 Canadian dollars. RESULTS: Overall, 88,935 individuals contributed 443,847 person-years of follow-up (57% of female sex, mean age 31 years). Public drug subsidy decreased by -$41.74 (95% CI, -$28.34 to -$55.13) at the $15,000-deductible threshold, a 28% reduction, and patient costs increased by $48.45 (95% CI, $35.37-$61.53). The $30,000 deductible threshold did not affect public drug costs (P = .31), but patient costs increased by $27.65 (95% CI, $15.22-$40.09), which is an 11% increase. Asthma-related medication use, inhaled corticosteroids-to-total medication ratio, excessive use of short-acting ß-agonists, and proportion of days covered by controller therapies were not impacted by deductible thresholds. CONCLUSION: Income-based deductibles reduced public drug costs with no effect on asthma-related medication use, adherence to controller therapies, or excessive reliever therapy use in lower-income individuals with asthma.


Asunto(s)
Antiasmáticos , Asma , Adulto , Niño , Humanos , Femenino , Deducibles y Coseguros , Asma/tratamiento farmacológico , Colombia Británica , Renta , Corticoesteroides/uso terapéutico , Antiasmáticos/uso terapéutico , Cumplimiento de la Medicación
5.
Cancer Res Commun ; 4(1): 118-133, 2024 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-38147007

RESUMEN

Squamous cell carcinomas, which arise from the cells that line the mucosal surfaces of the head and neck, represent the most common type of head and neck cancers (HNSCC). Human papillomavirus (HPV) infection has been strongly associated with the development of oropharyngeal cancers, which are cancers that occur in the back of the throat, including the tonsils and base of the tongue. HNSCCs with and without HPV infection have distinct pathology, with HPV-positive patients having higher levels of immune infiltration, activation in the tumor microenvironment and better response to radiation and chemotherapy. It is, however, unclear whether HPV infection in HNSCCs has the potential to activate innate-immune sensing pathways and if these cancers possess intrinsic immunogenicity associated with HPV infection. Here we investigate the innate immune stimulator of interferon genes (STING) pathway and immune responses to STING activation in HNSCCs and uncover fundamental differences in the regulation of this pathway in cell lines versus primary human clinical specimens. We show that while STING is differentially expressed in HPV-positive and -negative HNSCC cell lines, they exhibit a gross functional defect in signaling through this pathway. However, STING activation in immune cell populations generated immune signatures predicted to elicit useful tumoricidal mechanisms. In contrast, IHC analysis of human tissue microarrays revealed enhanced STING expression in HPV-related tumors and high intratumoral expression of STING correlated with increased survival. SIGNIFICANCE: STING is an important innate immune sensor of cytosolic DNA, inducing essential antiviral and antitumoral responses. This research shows that STING expression is enhanced in HPV-positive HNSCC patient tissue, with high intratumoral STING expression correlating with increased survival. In addition, STING activation in immune cell populations augmented antitumoral effects against HNSCCs, suggesting patients may benefit from the use of STING agonists in combination with traditional therapies.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/complicaciones , Infecciones por Papillomavirus/complicaciones , Neoplasias de Cabeza y Cuello/complicaciones , Carcinoma de Células Escamosas/complicaciones , Virus del Papiloma Humano , Microambiente Tumoral
6.
Palliat Care Soc Pract ; 17: 26323524231212515, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38033874

RESUMEN

Background: The core to successful advance care planning (ACP) facilitation is helping people determine their values, beliefs and wishes, and understand substitute decision-making. Recognizing the potential for community members to support public awareness and education we developed a model of ACP education, whereby peer facilitators associated with community organizations host workshops that educate and assist members of the public with ACP. Objectives: Describe the development and evaluation of the model for community-led peer-facilitated ACP workshops for the public. Design: Descriptive mixed methods. Methods: A training curriculum and program model were co-developed with two community organizations that had been successful in delivering ACP workshops independently in their communities. Herein we describe a mixed-methods evaluation of three cycles of implementation and improvement of the model. Results: The model centers on three key concepts; the right content (based around three steps Think, Talk, Plan), the right facilitator, and the right approach. A suite of tools was designed to support the three groups involved in the delivery of the ACP workshops: the public participants, the peer facilitators, and the community-based organizations. The peer-facilitator training addresses the facilitator's learning needs of ACP content knowledge, facilitation skills, and understanding change behavior. Training evaluation data from 106 facilitators confirmed that the curriculum prepared them to facilitate the workshops. Qualitative data revealed that support from organizations with established reputations in their community is critical, with mentoring from more experienced facilitators beneficial. Conclusion: Our model demonstrates the potential of community-led, peer-facilitated ACP initiatives to enhance the capacity of community to upstream ACP conversations. Reaching a broader audience and creating a supportive, inclusive environment for individuals to comfortably learn about ACP can drive the much-needed culture shift to normalize ACP. Meaningful community engagement, empowerment, and partnerships are essential for the successful development and widespread impact of these initiatives.


A model for community-led peer-facilitated advance care planning workshops for the public Why was this study done? Advance care planning (ACP) allows people to reflect on and share their personal values, goals and preferences as they relate to their future healthcare. Despite the benefits of doing ACP, the number of people who have engaged in ACP remains low. Traditionally, most ways of supporting people to engage in ACP have involved healthcare providers. In British Columbia, two community-based organizations had developed successful peer-facilitated workshops to engage and educate the public. In these workshops, non-expert members of the community (peer-facilitators) conduct interactive workshops that help members of the public understand and begin ACP. What did the researchers do? We partnered with these two organizations to develop a training curriculum and other materials required to spread this approach to other community organizations throughout the province. The model is based on three key concepts: the right content, the right facilitator, and the right approach. The materials include a suite of tools for three groups: the public participants, the peer-facilitators and the organizations. What did the researchers find? The training and suite of tools we developed successfully prepared community members ("peers") associated with community organizations to facilitate ACP workshops for the public. Support from community organizations is essential, and mentoring from more experienced facilitators is beneficial. What do the findings mean? As a provincial organization we were able to successfully partner with community organizations to develop a model and spread the workshops provincially and confirm they were acceptable and effective, improving public access to information about advance care planning.

7.
J Biol Chem ; 299(12): 105353, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37858677

RESUMEN

The PD-1/PD-L1 checkpoint pathway is important for regulating immune responses and can be targeted by immunomodulatory drugs to treat a variety of immune disorders. However, the precise protein-protein interactions required for the initiation of PD-1/PD-L1 signaling are currently unknown. Previously, we designed a series of first-generation PD-1 targeting peptides based on the native interface region of programmed death ligand 1 (PD-L1) that effectively reduced PD-1/PD-L1 binding. In this work, we further characterized the previously identified lead peptide, MN1.1, to identify key PD-1 binding residues and design an optimized peptide, MN1.4. We show MN1.4 is significantly more stable than MN1.1 in serum and retains the ability to block PD-1/PD-L1 complex formation. We further characterized the immunomodulatory effects of MN1.4 treatment by measuring markers of T cell activation in a co-culture model with ovarian cancer cells and peripheral blood mononuclear cells. We found MN1.4 treatment reduced cytokine secretion and suppressed T cell responses in a similar manner as recombinant PD-L1. Therefore, the PD-L1 interface region used to design MN1.4 appeared sufficient to initiate PD-1 signaling and likely represents the minimum necessary region of PD-L1 required for PD-1 recognition. We propose a peptide agonist for PD-1, such as MN1.4, could have several applications for treating autoimmune disorders caused by PD-1 deficiencies such as type 1 diabetes, inflammatory arthritis, or autoimmune side effects arising from monoclonal antibody-based cancer immunotherapies.


Asunto(s)
Antígeno B7-H1 , Modelos Moleculares , Neoplasias , Transducción de Señal , Humanos , Antígeno B7-H1/química , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Inmunoterapia , Leucocitos Mononucleares/metabolismo , Neoplasias/tratamiento farmacológico , Péptidos/farmacología , Receptor de Muerte Celular Programada 1/agonistas , Receptor de Muerte Celular Programada 1/química , Receptor de Muerte Celular Programada 1/metabolismo , Unión Proteica , Mutación , Estructura Cuaternaria de Proteína , Línea Celular Tumoral , Inmunidad/efectos de los fármacos
8.
Cancer Drug Resist ; 6(6): 468-480, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37840856

RESUMEN

Aim: Ferroptosis is a non-apoptotic form of cell death caused by lethal lipid peroxidation. Several small molecule ferroptosis inducers (FINs) have been reported, yet little information is available regarding their interaction with the ATP-binding cassette (ABC) transporters P-glycoprotein (P-gp, ABCB1) and ABCG2. We thus sought to characterize the interactions of FINs with P-gp and ABCG2, which may provide information regarding oral bioavailability and brain penetration and predict drug-drug interactions. Methods: Cytotoxicity assays with ferroptosis-sensitive A673 cells transfected to express P-gp or ABCG2 were used to determine the ability of the transporters to confer resistance to FINs; confirmatory studies were performed in OVCAR8 and NCI/ADR-RES cells. The ability of FINs to inhibit P-gp or ABCG2 was determined using the fluorescent substrates rhodamine 123 or purpuin-18, respectively. Results: P-gp overexpression conferred resistance to FIN56 and the erastin derivatives imidazole ketone erastin and piperazine erastin. P-gp-mediated resistance to imidazole ketone erastin and piperazine erastin was also reversed in UO-31 renal cancer cells by CRISPR-mediated knockout of ABCB1. The FINs ML-162, GPX inhibitor 26a, and PACMA31 at 10 µM were able to increase intracellular rhodamine 123 fluorescence over 10-fold in P-gp-expressing MDR-19 cells. GPX inhibitor 26a was able to increase intracellular purpurin-18 fluorescence over 4-fold in ABCG2-expressing R-5 cells. Conclusion: Expression of P-gp may reduce the efficacy of these FINs in cancers that express the transporter and may prevent access to sanctuary sites such as the brain. The ability of some FINs to inhibit P-gp and ABCG2 suggests potential drug-drug interactions.

9.
BMC Prim Care ; 24(1): 197, 2023 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-37743490

RESUMEN

BACKGROUND: Advance care planning (ACP) is a process intended to help ensure people receive medical care that is consistent with their values, goals, and preferences during serious and chronic illness. Barriers to implementing ACP in primary care settings exist. Community-led ACP initiatives exist in British Columbia to engage the public directly. These initiatives may help prepare people for conversations with their primary care providers. The objectives of this study were to elicit primary care providers' perceptions of the utility and desired content of community-led ACP activities and suggestions for integrating community-led ACP activities with primary care. METHODS: We conducted an online cross-sectional survey of primary care providers practicing in British Columbia, Canada in 2021. Both quantitative and qualitative survey questions addressed ACP engagement in practice, the perceived role and desired outcomes of community-led ACP activities, and ways to integrate community-led ACP activities with primary care. RESULTS: Eighty-one providers responded. Over 80% perceived a moderate or greater potential impact of community-led ACP activities. The most common reasons for not referring a patient to a community-led ACP activity were lack of awareness of the option locally (62.1%) and in general (44.8%). Respondents wanted their patients to reflect on their values, wishes and preferences for care, to have at least thought about their goals of care and to have chosen a substitute decision maker in the community. They indicated a desire for a summary of their patient's participation and a follow-up discussion with them about their ACP. They suggested ways to integrate referral to programs into existing health care system structures. CONCLUSIONS: Community-led ACP activities were perceived to be useful to engage and prepare patients to continue ACP discussions with clinicians. Efforts should be made to establish and integrate community-based ACP initiatives within existing primary care systems to ensure awareness and uptake.


Asunto(s)
Planificación Anticipada de Atención , Humanos , Estudios Transversales , Transporte Biológico , Colombia Británica , Atención Primaria de Salud
10.
PEC Innov ; 3: 100199, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37662691

RESUMEN

Objective: Despite recognized benefits, engagement in Advance Care Planning (ACP) remains low. Research into peer-facilitated, group ACP interventions is limited. This study investigated the acceptability of community-led peer-facilitated ACP workshops for the public and whether these workshops are associated with increased knowledge, motivation and engagement in ACP behaviors. Methods: Peer-facilitators from 9 community organizations were recruited and trained to deliver free ACP workshops to members of the public with an emphasis on conversation. Using a cohort design, workshop acceptability and engagement in ACP behaviors was assessed by surveying public participants at the end of the workshop and 4-6 weeks later. Results: 217 participants returned post-workshop questionnaires, and 69 returned follow-up questionnaires. Over 90% of participants felt they gained knowledge across all 6 learning goals. Every ACP behavior saw a statistically significant increase in participant completion after 4-6 weeks. Almost all participants were glad they attended (94%) and would recommend the workshop to others (95%). Conclusion: This study revealed an association of peer-facilitated ACP workshops and completion of ACP behaviors in public participants. Innovation: This innovative approach supports investment in the spread of community-based, peer-facilitated ACP workshops for the public as important ACP promotion strategies.

11.
Nanoscale ; 15(42): 16924-16932, 2023 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-37591812

RESUMEN

To reach energy density demands greater than 3 mA h cm-2 for practical applications, the electrode structure of lithium-sulfur batteries must undergo an architectural redesign. Freestanding carbon nanofoam papers derived from resorcinol-formaldehyde aerogels provide a three-dimensional conductive mesoporous network while facilitating electrolyte transport. Vapor-phase sulfur infiltration fully penetrates >100 µm thick electrodes and conformally coats the carbon aerogel surface providing areal capacities up to 4.1 mA h cm-2 at sulfur loadings of 6.4 mg cm-2. Electrode performance can be optimized for energy density or power density by tuning sulfur loading, pore size, and electrode thickness.

12.
Death Stud ; : 1-10, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37561057

RESUMEN

It is common for the bereaved who are experiencing homelessness to be unrecognized grievers, who are then not adequately supported in their bereavement. This rapid review gathered published information from 17 references on how bereavement is experienced within the context of homelessness (from 509 references imported for screening). Four themes identified for understanding the bereavement experience were bereavement as a risk factor for homelessness, anticipatory grief, increased frequency of death, and ways of processing grief. Current practices used for support were themed into memorials, advocacy, and trauma-informed care. Themes for gaps and barriers to support were bereavement being systematically overlooked and environmental features present. The summary of findings is intended to help inform future research, policy, legislation, and cultural responses to grief and bereavement with the hope it may reduce people's grief from being disenfranchized.

13.
Patient Educ Couns ; 115: 107925, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37499447

RESUMEN

OBJECTIVE: Community-led approaches can increase public engagement in Advance Care Planning (ACP). Better understanding of the experiences and perspectives of community staff and volunteers who host and facilitate community-led, peer-facilitated ACP workshops is valuable when considering the spread of these approaches. METHODS: Content analysis of qualitative data from community-based hospice societies delivering ACP workshops to the public in British Columbia: one-on-one interviews with 5 organizational representatives and focus groups with 13 peer facilitators. RESULTS: Three main categories emerged: 1) ACP is about 'Living well'; 2) Transitioning focus from legal forms to conversations; 3) Benefits to all involved. CONCLUSIONS: Community staff and volunteers acknowledge the role they could play in promoting ACP in their communities. They recognize the benefits to the facilitators and public participants from following a community-led approach that emphasizes the importance of ACP conversations over the completion of relevant legal forms. Additional potential benefits of this approach, as reported by the organizational representatives, are increased volunteer engagement, more community partnerships, and an enhanced organizational profile. PRACTICE IMPLICATIONS: This community-led model can be a meaningful and approachable way to engage the public in ACP. Hospice societies are well positioned in the community to incorporate ACP workshops into their programming.


Asunto(s)
Planificación Anticipada de Atención , Cuidados Paliativos al Final de la Vida , Hospitales para Enfermos Terminales , Humanos , Grupos Focales , Voluntarios
14.
BMC Health Serv Res ; 23(1): 397, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-37095499

RESUMEN

BACKGROUND: Globally, the COVID-19 pandemic had a huge impact on patients and healthcare systems. A decline in paediatric visits to healthcare settings was observed, which might have been due to lower incidence of injury and infectious illness, changes in healthcare services and parental concern. The aim of our study was to examine parental experiences of help-seeking for, and care of, a sick or injured child during COVID-19 lockdown periods in five European countries with different healthcare systems in place. METHODS: An online survey for parents with a child with any kind or illness of injury during COVID-19 lockdowns was circulated through social media in five European countries: Italy, Spain, Sweden, the Netherlands, and the United Kingdom. Parents living in one of these countries with self-identification of a sick or injured child during COVID-19 lockdown periods were eligible to fill in the survey. Descriptive statistics were used for the level of restrictions per country, children's characteristics, family characteristics and reported help-seeking behaviour of parents prior to the lockdown and their real experience during the lockdown. The free text data was subjected to thematic analysis. RESULTS: The survey was fully completed by 598 parents, ranging from 50 to 198 parents per country, during varying lockdown periods from March 2020 until May 2022. Parents who completed the survey were not deterred from seeking medical help for their sick or injured child during the COVID-19 pandemic. This finding was comparable in five European countries with different healthcare systems in place. Thematic analysis identified three main areas: parental experiences of access to healthcare, changes in parents' help-seeking behaviours for a sick or injured child during lockdowns, and the impact of caring for a sick or injured child during the lockdowns. Parents reported limited access to non-urgent care services and were anxious about either their child or themselves catching COVID-19. CONCLUSION: This insight into parental perspectives of help-seeking behaviour and care for a sick or injured child during COVID-19 lockdowns could inform future strategies to improve access to healthcare, and to provide parents with adequate information concerning when and where to seek help and support during pandemics.


Asunto(s)
COVID-19 , Conducta de Búsqueda de Ayuda , Niño , Humanos , Pandemias , Control de Enfermedades Transmisibles , Padres
15.
bioRxiv ; 2023 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-36945397

RESUMEN

Ferroptosis is a form of cell death caused by direct or indirect inhibition of glutathione peroxidase 4 that leads to lethal lipid peroxidation. Several small molecule ferroptosis inducers (FINs) have been reported, yet little information is available regarding resistance mechanisms, particularly their interaction with the ATP-binding cassette (ABC) transporters P-glycoprotein (P-gp, ABCB1) and ABCG2. Given the role that ABC transporters play in absorption, distribution, and excretion of many drugs, characterizing these interactions could provide information regarding oral bioavailability and brain penetration and may predict drug-drug interactions. Using ferroptosis-sensitive A673 cells transfected to express P-gp or ABCG2, we found that P-gp overexpression was able to confer resistance to FIN56 and the erastin derivatives imidazole ketone erastin and piperazine erastin. Results were confirmed with OVCAR8-derived NCI/ADR-RES cells that overexpress P-gp, where the P-gp inhibitor valspodar completely inhibited resistance to the FINs. P-gp-mediated resistance to imidazole ketone erastin and piperazine erastin was also reversed in UO-31 renal cancer cells by CRISPR-mediated knockout of ABCB1. At a concentration of 10 µM, the FINs ML-162, GPX inhibitor 26a, and PACMA31 were able to increase intracellular rhodamine 123 fluorescence over 10-fold in P-gp-expressing MDR-19 cells and GPX inhibitor 26a was able to increase intracellular purpurin-18 fluorescence over 4-fold in ABCG2-expressing R-5 cells. Expression of P-gp may reduce the efficacy of these FINs in cancers that express the transporter and may prevent access to sanctuary sites such as the brain. The ability of some FINs to inhibit P-gp and ABCG2 suggests potential drug-drug interactions.

17.
ACS Omega ; 7(26): 22317-22325, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35811924

RESUMEN

There have been tremendous improvements in the field of Si electrode materials, either by nanoscale or composite routes, and though silicon-containing carbon electrode materials have begun to penetrate the marketplace, the commercial capacities achieved by these cells still fall short of the promise of high capacity Si electrodes. Enabling a cheaper feedstock of Si in the bulk form would make this technology more accessible, though there are many challenges that must be overcome. Whereas other methods utilize nanomaterials and composites to overcome volume expansion and pulverization of a Si electrode, this study explores a thermal route to enable the use of carbon-free bulk Si. To accomplish this, a modified Swagelok cell has been constructed to accommodate high temperatures, corrosive molten salt electrolytes, and a molten lithium electrode to study lithiation of a bulk Si wafer at 250 °C. Scanning electron microscopy, X-ray diffraction, and microcomputed tomography were used to examine morphological and structural changes within the Si upon lithiation and delithiation. It was discovered that semiordered Li x Si phases were formed upon lithiation in molten LiTFSI electrolyte at 250 °C, and the higher temperature does not completely mitigate pulverization of the bulk Si electrode.

18.
J Extracell Vesicles ; 11(7): e12244, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35879267

RESUMEN

We characterized the in vivo interstitial fluid (IF) content of extracellular vesicles (EVs) using the GFP-4T1 syngeneic murine cancer model to study EVs in-transit to the draining lymph node. GFP labelling confirmed the IF EV tumour cell origin. Molecular analysis revealed an abundance of IF EV-associated proteins specifically involved in mitophagy and secretory autophagy. A set of proteins required for sequential steps of fission-induced mitophagy preferentially populated the CD81+/PD-L1+ IF EVs; PINK1, TOM20, and ARIH1 E3 ubiquitin ligase (required for Parkin-independent mitophagy), DRP1 and FIS1 (mitochondrial peripheral fission), VDAC-1 (ubiquitination state triggers mitophagy away from apoptosis), VPS35, SEC22b, and Rab33b (vacuolar sorting). Comparing in vivo IF EVs to in vitro EVs revealed 40% concordance, with an elevation of mitophagy proteins in the CD81+ EVs for both murine and human cell lines subjected to metabolic stress. The export of cellular mitochondria proteins to CD81+ EVs was confirmed by density gradient isolation from the bulk EV isolate followed by anti-CD81 immunoprecipitation, molecular sieve chromatography, and MitoTracker export into CD81+ EVs. We propose the 4T1 in vivo model as a versatile tool to functionally characterize IF EVs. IF EV export of fission mitophagy proteins has broad implications for mitochondrial function and cellular immunology.


Asunto(s)
Vesículas Extracelulares , Neoplasias , Animales , Líquido Extracelular/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Ratones , Mitofagia , Proteínas Quinasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas de Transporte Vesicular
19.
Cell Death Dis ; 13(5): 436, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35508606

RESUMEN

The recruitment of DRP1 to mitochondrial membranes prior to fission is facilitated by the wrapping of endoplasmic reticulum (ER) membranes around the mitochondria. To investigate the complex interplay between the ER membranes and DRP1 in the context of mitochondrial structure and function, we downregulate two key ER shaping proteins, RTN4 and CLIMP-63, and demonstrate pronounced mitochondrial hyperfusion and reduced ER-mitochondria contacts, despite their differential regulation of ER architecture. Although mitochondrial recruitment of DRP1 is unaltered in cells lacking RTN4 or CLIMP-63, several aspects of mitochondrial function, such as mtDNA-encoded translation, respiratory capacity and apoptosis are significantly hampered. Further mechanistic studies reveal that CLIMP-63 is required for cristae remodeling (OPA1 proteolysis) and DRP1-mediated mitochondrial fission, whereas both RTN4 and CLIMP-63 regulate the recruitment of BAX to ER and mitochondrial membranes to enable cytochrome c release and apoptosis, thereby performing novel and distinct roles in the regulation of mitochondrial structure and function.


Asunto(s)
Dinaminas , Mitocondrias , Apoptosis/genética , Dinaminas/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo , Dinámicas Mitocondriales , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo
20.
Health Expect ; 25(1): 345-354, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34904336

RESUMEN

BACKGROUND: Despite the established benefits of Advance Care Planning (ACP), engagement remains low in British Columbia. Since 2016, a growing number of community-based nonprofits have offered ACP education. To date, no study has focused on the perspectives of nonprofits on ACP in British Columbia. OBJECTIVE: This study aimed to identify barriers and facilitating actions to ACP as perceived by British Columbian nonprofits. DESIGN: A mixed-methods design was used. Data were collected through online surveys and telephone interviews. SETTING AND PARTICIPANTS: Staff and volunteers from British Columbian nonprofits that are providing or interested in providing public education on ACP were recruited for this study. RESULTS: The lack of public awareness of ACP, the emotional difficulty of the conversation, the complicated ACP process, the belief that ACP is synonymous with completing a medical order form, the challenge of introducing ACP in different cultural contexts and the siloed approach to ACP education were rated as the most important barriers to ACP engagement. The most important facilitating actions were developing clear messages, improving ACP literacy, reframing ACP as part of life planning, simplifying ACP documentation and transfer, integrating ACP conversations into clinical practice and better collaboration between the health system and nonprofits. DISCUSSION: This study identifies numerous opportunities to improve ACP engagement in British Columbia from a community lens. To maximize ACP engagement, community-led ACP education should be offered in coordination with the health system. CONCLUSION: Community-led ACP education as well as collaboration and consultation with nonprofits are part of the solution to the low ACP engagement in British Columbia. PUBLIC CONTRIBUTION: Study participants, including staff and volunteers at nonprofits, are members of the public.


Asunto(s)
Planificación Anticipada de Atención , Colombia Británica , Comunicación , Humanos , Encuestas y Cuestionarios
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