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1.
Proc Natl Acad Sci U S A ; 117(14): 8022-8031, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32213589

RESUMO

Innate immune receptors such as toll-like receptors (TLRs) provide critical molecular links between innate cells and adaptive immune responses. Here, we studied the CD40 pathway as an alternative bridge between dendritic cells (DCs) and adaptive immunity in cancer. Using an experimental design free of chemo- or radiotherapy, we found CD40 activation with agonistic antibodies (⍺CD40) produced complete tumor regressions in a therapy-resistant pancreas cancer model, but only when combined with immune checkpoint blockade (ICB). This effect, unachievable with ICB alone, was independent of TLR, STING, or IFNAR pathways. Mechanistically, αCD40/ICB primed durable T cell responses, and efficacy required DCs and host expression of CD40. Moreover, ICB drove optimal generation of polyfunctional T cells in this "cold" tumor model, instead of rescuing T cell exhaustion. Thus, immunostimulation via αCD40 is sufficient to synergize with ICB for priming. Clinically, combination αCD40/ICB may extend efficacy in patients with "cold" and checkpoint-refractory tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antígenos CD40/agonistas , Carcinoma Ductal Pancreático/tratamento farmacológico , Neoplasias/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígenos CD40/imunologia , Antígenos CD40/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/imunologia , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neoplasias/imunologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
2.
J Clin Psychol ; 73(3): 218-232, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27377826

RESUMO

OBJECTIVE: Seligman, Steen, Park, and Peterson (2005) suggested that positive psychology interventions (PPIs) contain specific, powerful, therapeutic ingredients that effect greater increases in happiness and reductions in depression than a placebo control. This study reexamined the three PPIs that Seligman et al. found to be most effective when delivered over the internet. METHOD: Three PPIs and a placebo control, identical with the interventions used by Seligman et al., were examined in a web-based, randomized assignment design. RESULTS: Mixed-design analysis of variance and multilevel modeling showed that all interventions, including the placebo, led to significant increases in happiness and reductions in depression. The effects of PPIs were indistinguishable from those of the placebo control. CONCLUSION: Using web-based delivery, both PPIs and theoretically neutral placebos can increase happiness and reduce depression in self-selected populations. Possible explanations include that non-specific factors common to most therapeutic treatments are responsible for the observed changes, or that cultural or other context-related variables operate to account for the divergent findings.


Assuntos
Depressão/terapia , Avaliação de Resultados em Cuidados de Saúde , Psicoterapia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Atitude , Emoções , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Adulto Jovem
3.
BMC Health Serv Res ; 15: 283, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26205006

RESUMO

BACKGROUND: Mental illness is prevalent across the globe and affects multiple aspects of life. Despite advances in treatment, there is little evidence that prevalence rates of mental illness are falling. While the prevention of cardiovascular disease and cancers are common in the policy dialogue and in service delivery, the prevention of mental illness remains a neglected area. There is accumulating evidence that mental illness is at least partially preventable, with increasing recognition that its antecedents are often found in infancy, childhood, adolescence and youth, creating multiple opportunities into young adulthood for prevention. Developing valid and reproducible methods for translating the evidence base in mental illness prevention into actionable policy recommendations is a crucial step in taking the prevention agenda forward. METHOD: Building on an aetiological model of adult mental illness that emphasizes the importance of intervening during infancy, childhood, adolescence and youth, we adapted a workforce and service planning framework, originally applied to diabetes care, to the analysis of the workforce and service structures required for best-practice prevention of mental illness. RESULTS: The resulting framework consists of 6 steps that include identifying priority risk factors, profiling the population in terms of these risk factors to identify at-risk groups, matching these at-risk groups to best-practice interventions, translation of these interventions to competencies, translation of competencies to workforce and service estimates, and finally, exploring the policy implications of these workforce and services estimates. The framework outlines the specific tasks involved in translating the evidence-base in prevention, to clearly actionable workforce, service delivery and funding recommendations. CONCLUSIONS: The framework describes the means to deliver mental illness prevention that the literature indicates is achievable, and is the basis of an ongoing project to model the workforce and service structures required for mental illness prevention.


Assuntos
Prática Clínica Baseada em Evidências , Planejamento em Saúde , Mão de Obra em Saúde , Transtornos Mentais/prevenção & controle , Adulto , Feminino , Humanos , Masculino , Fatores de Risco
5.
Sci Total Environ ; 946: 174369, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38955282

RESUMO

River invertebrate communities across Europe have been changing in response to variations in water quality over recent decades, but the underlying drivers are difficult to identify because of the complex stressors and environmental heterogeneity involved. Here, using data from ∼4000 locations across England and Wales, collected over 29 years, we use three approaches to help resolve the drivers of spatiotemporal variation in the face of this complexity: i) mapping changes in invertebrate richness and community composition; ii) structural equation modelling (SEM) to distinguish land cover, water quality and climatic influences; and iii) geographically weighted regression (GWR) to identify how the apparent relationships between invertebrate communities and abiotic variables change across the area. Mapping confirmed widespread increases in richness and the proportion of pollution-sensitive taxa across much of England and Wales. It also revealed regions where pollution-sensitive taxa or overall richness declined, the former primarily in the uplands. SEMs confirmed strong increases in average biochemical oxygen demand and nutrient concentrations related to urban and agricultural land cover, but only a minority of land cover's effect upon invertebrate communities was explained by average water chemistry, highlighting potential factors such as episodic extremes or emerging contaminants. GWR identified strong geographical variation in estimated relationships between macroinvertebrate communities and environmental variables, with evidence that the estimated negative impacts of nutrients and water temperature were increasing through time. Overall the results are consistent with widespread biological recovery of Britain's rivers from past gross organic pollution, whilst highlighting declines in some of the most diverse and least impacted streams. Modelling points to a complex and changing set of drivers, highlighting the multifaceted impacts of catchment land cover and the evolving role of different stressors, with the relationship to gross organic pollution weakening, whilst estimated nutrient and warming effects strengthened.


Assuntos
Monitoramento Ambiental , Invertebrados , Rios , Rios/química , País de Gales , Inglaterra , Animais , Invertebrados/fisiologia , Qualidade da Água , Ecossistema , Biodiversidade
6.
Nat Commun ; 15(1): 1532, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38378697

RESUMO

Acquired resistance to immunotherapy remains a critical yet incompletely understood biological mechanism. Here, using a mouse model of pancreatic ductal adenocarcinoma (PDAC) to study tumor relapse following immunotherapy-induced responses, we find that resistance is reproducibly associated with an epithelial-to-mesenchymal transition (EMT), with EMT-transcription factors ZEB1 and SNAIL functioning as master genetic and epigenetic regulators of this effect. Acquired resistance in this model is not due to immunosuppression in the tumor immune microenvironment, disruptions in the antigen presentation machinery, or altered expression of immune checkpoints. Rather, resistance is due to a tumor cell-intrinsic defect in T-cell killing. Molecularly, EMT leads to the epigenetic and transcriptional silencing of interferon regulatory factor 6 (Irf6), rendering tumor cells less sensitive to the pro-apoptotic effects of TNF-α. These findings indicate that acquired resistance to immunotherapy may be mediated by programs distinct from those governing primary resistance, including plasticity programs that render tumor cells impervious to T-cell killing.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Linhagem Celular Tumoral , Recidiva Local de Neoplasia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/metabolismo , Imunoterapia , Transição Epitelial-Mesenquimal/genética , Microambiente Tumoral
8.
Sci Total Environ ; 878: 163107, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36972879

RESUMO

Uncertainty around the changing ecological status of European rivers reflects an evolving array of anthropogenic stressors, including climate change. Although previous studies have revealed some recovery from historical pollution in the 1990s and early-2000s, there are contrasting trends among pollutants across Europe and recovery may have stalled or been reversed. To provide more contemporary evidence on trends and status, here we investigate changes in English and Welsh river macroinvertebrate communities over almost 30 years (1991-2019) using a network of nearly 4000 survey locations. Analysis comprised: i) trends in taxonomic and functional richness, community composition and ecological traits, ii) gains, losses and turnover of taxa, and the overall homogeneity of macroinvertebrate communities nationally, and iii) an exploration of how temporal trends varied with catchment characteristics. Taxonomic richness increased, primarily in the 1990s, whilst a shift towards pollution-sensitive taxa continued throughout the study period, accompanied by a growing prevalence in traits such as preferences for fast-flowing conditions, coarser substrata, and 'shredding' or 'scraping' feeding strategies. Changes consistent with improvement occurred in both urbanised and agricultural catchments, but were more pronounced in urban rivers as they gained pollution sensitive taxa that were otherwise more prevalent in rural rivers. Overall, these results indicate continuing biological recovery from organic pollution, consistent with national scale trends in water quality. Results reemphasise the importance of looking at multiple facets of diversity, with periods of near-constant richness disguising changes in taxonomic and functional composition. Whilst this national-scale picture is broadly positive, we highlight the need to investigate more local variations or pollutants that depart from this aggregate picture.


Assuntos
Poluentes Ambientais , Invertebrados , Animais , Biodiversidade , Ecossistema , Monitoramento Ambiental , Rios , Qualidade da Água , Poluição da Água
9.
Res Sq ; 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37398248

RESUMO

Acquired resistance to immune checkpoint immunotherapy remains a critical yet incompletely understood biological mechanism. Here, using a mouse model of pancreatic ductal adenocarcinoma (PDAC) to study tumor relapse following immunotherapy-induced responses, we found that tumors underwent an epithelial-to-mesenchymal transition (EMT) that resulted in reduced sensitivity to T cell-mediated killing. EMT-transcription factors (EMT-TFs) ZEB1 and SNAIL function as master genetic and epigenetic regulators of this tumor-intrinsic effect. Acquired resistance was not due to immunosuppression in the tumor immune microenvironment, disruptions in the antigen presentation machinery, or altered expression of immune checkpoints. Rather, EMT was associated with epigenetic and transcriptional silencing of interferon regulatory factor 6 (Irf6), which renders tumor cells less sensitive to the pro-apoptotic effects of TNF-α. These findings show how resistance to immunotherapy in PDAC can be acquired through plasticity programs that render tumor cells impervious to T cell killing.

11.
Med J Aust ; 194(8): 414-6, 2011 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-21495943

RESUMO

Multidose vials (MDVs) for injectable therapeutic agents, including vaccines, pose a risk of infection to injected patients as a result of contamination of the vials. The Australian Government Department of Health and Ageing (DoHA) distributed the vaccine against pandemic (H1N1) 2009 influenza in MDVs. The distribution was accompanied by consent forms. The consent forms provided an inadequate basis for a discussion with patients about the risks associated with the use of MDVs. The High Court of Australia has previously held that medical practitioners who fail to explain the material risks of medical procedures to their patients might be held liable in negligence for any adverse sequelae of the procedures, even if the risks are very low. Medical practitioners, nurses, medical indemnity insurers and the DoHA should prepare now for the probable future use of MDVs by developing a consent form that would provide a solid foundation for a discussion of material risks with patients seeking vaccination.


Assuntos
Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Consentimento Livre e Esclarecido/legislação & jurisprudência , Vacinação/legislação & jurisprudência , Austrália/epidemiologia , Humanos , Influenza Humana/epidemiologia , Pandemias , Guias de Prática Clínica como Assunto , Vacinas Combinadas
12.
Clin Anat ; 24(2): 151-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21322037

RESUMO

The Hebrew writings in early history are dedicated primarily to the explanations and elucidations of Jewish law. In the context of such laws, several medical and anatomical references are made that provide some clues to the medical practices of the day. In particular, this article serves to compile references made to surgical interventions within these texts. Particular attention is paid to the possible use of anesthetics, the environment and equipment utilized in surgery, as well as the indication of knowledge of infection and hygienic practices. An understanding of human morphology was necessary for many of these surgical practices.


Assuntos
Cirurgia Geral/história , Judaísmo/história , Procedimentos Cirúrgicos Operatórios , Anestesia/história , História Antiga , História Medieval , Humanos
13.
Clin Anat ; 24(1): 10-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20941708

RESUMO

The facial nerve (CN VII) nerve follows a torturous and complex path from its emergence at the pontomedullary junction to its various destinations. It exhibits a highly variable and complicated branching pattern and forms communications with several other cranial nerves. The facial nerve forms most of these neural intercommunications with branches of all three divisions of the trigeminal nerve (CN V), including branches of the auriculotemporal, buccal, mental, lingual, infraorbital, zygomatic, and ophthalmic nerves. Furthermore, CN VII also communicates with branches of the vestibulocochlear nerve (CN VIII), glossopharyngeal nerve (CN IX), and vagus nerve (CN X) as well as with branches of the cervical plexus such as the great auricular, greater, and lesser occipital, and transverse cervical nerves. This review intends to explore the many communications between the facial nerve and other nerves along its course from the brainstem to its peripheral branches on the human face. Such connections may have importance during clinical examination and surgical procedures of the facial nerve. Knowledge of the anatomy of these neural connections may be particularly important in facial reconstructive surgery, neck dissection, and various nerve transfer procedures as well as for understanding the pathophysiology of various cranial, skull base, and neck disorders.


Assuntos
Face/inervação , Nervo Facial/anatomia & histologia , Nervo Facial/cirurgia , Nervo Glossofaríngeo/anatomia & histologia , Humanos , Nervo Trigêmeo/anatomia & histologia , Nervo Vago/anatomia & histologia , Nervo Vestibulococlear/anatomia & histologia
14.
Cancer Immunol Res ; 9(8): 877-890, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34145076

RESUMO

T-cell recognition of tumor neoantigens is critical for cancer immune surveillance and the efficacy of immunotherapy. Tumors can evade host immunity by altering their antigenicity or orchestrating an immunosuppressive microenvironment, leading to outgrowth of poorly immunogenic tumors through the well-established process of cancer immunoediting. Whether cancer immune surveillance and immunoediting depend on the tissue site of origin, however, is poorly understood. Herein, we studied T-cell-mediated surveillance of antigenic, clonal murine pancreatic adenocarcinoma cells expressing neoantigen. Whereas such tumors are robustly eliminated after subcutaneous or intravenous challenge, we observed selective immune escape within the pancreas and peritoneum. Tumor outgrowth occurred in the absence of immunoediting, and antitumor immunity could not be rescued by PD-1 or CTLA-4 checkpoint blockade. Instead, tumor escape was associated with diminished CD8+ T-cell priming by type I conventional dendritic cells (cDC1). Enhancing cDC1 cross-presentation by CD40 agonist treatment restored immunologic control by promoting T-cell priming and broadening T-cell responses through epitope spread. These findings demonstrate that immune escape of highly antigenic tumors can occur without immunoediting in a tissue-restricted manner and highlight barriers to cDC1-mediated T-cell priming imposed by certain microenvironments that must be addressed for successful combination immunotherapies.


Assuntos
Apresentação Cruzada/imunologia , Células Dendríticas/imunologia , Imunoterapia/métodos , Evasão Tumoral/imunologia , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Microambiente Tumoral
15.
Sarcoma ; 2021: 9712070, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814964

RESUMO

PURPOSE: Practice patterns for treatment of localized adult pleomorphic rhabdomyosarcoma (PRMS) remain quite variable given its rarity. Current national guidelines recommend management similar to that of other high-grade soft tissue sarcomas (STS), which include surgery with perioperative radiation (RT) with or without chemotherapy. Using the National Cancer Database (NCDB), we assessed practice patterns and overall outcomes of patients with localized PRMS. Patients and Methods. Patients with stage II/III PRMS treated with surgical resection from 2004 to 2015 were identified from the NCDB. Predictors of RT and chemotherapy use were assessed using multivariable logistic regression analysis. The association of radiation and chemotherapy status on overall survival was assessed using Kaplan-Meier and Cox proportional hazards analyses. RESULTS: Of 243 total patients, RT and chemotherapy were not uniformly utilized, with 44% receiving chemotherapy and in those who did not undergo amputation 62% receiving RT. In those who did not undergo amputation, RT was associated with improved survival on both univariate (HR: 0.49, 95% CI 0.32-0.73, P < 0.001) and multivariate analysis (HR: 0.40, 95% CI 0.26-0.62, P < 0.001), corresponding to greater 5-year overall survival (59% vs. 38%, P < 0.001). Chemotherapy was associated with a higher rate of 5-year overall survival (63% vs. 39%, P < 0.001). However, the survival benefit of chemotherapy did not reach statistical significance on multivariate analysis (HR: 0.65, 95% CI 0.41-1.03, P=0.064). Notable predictors of omission of RT included female gender (OR: 0.40, 95% CI 0.22-0.74, P < 0.01) and age ≥ 70 (OR: 0.55, 95% CI 0.30-1.00, P=0.05). Correspondingly, factors associated with omission of chemotherapy included age ≥70 (OR: 0.17, 95% CI 0.08-0.39, P < 0.001). CONCLUSIONS: A significant proportion of patients with localized adult PRMS are not receiving RT. Likewise, use of chemotherapy was heterogeneous. Our findings note potential benefits and underutilization of RT, for which further investigation is warranted.

16.
J Exp Bot ; 61(2): 473-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19933317

RESUMO

Chloroplasts produce reactive oxygen species (ROS) during cellular stress. ROS are known to act as regulators of programmed cell death (PCD) in plant and animal cells, so it is possible that chloroplasts have a role in regulating PCD in green tissue. Arabidopsis thaliana cell suspension cultures are model systems in which to test this, as here it is shown that their cells contain well-developed, functional chloroplasts when grown in the light, but not when grown in the dark. Heat treatment at 55 degrees C induced apoptotic-like (AL)-PCD in the cultures, but light-grown cultures responded with significantly less AL-PCD than dark-grown cultures. Chloroplast-free light-grown cultures were established using norflurazon, spectinomycin, and lincomycin and these cultures responded to heat treatment with increased AL-PCD, demonstrating that chloroplasts affect AL-PCD induction in light-grown cultures. Antioxidant treatment of light-grown cultures also resulted in increased AL-PCD induction, suggesting that chloroplast-produced ROS may be involved in AL-PCD regulation. Cycloheximide treatment of light-grown cultures prolonged cell viability and attenuated AL-PCD induction; however, this effect was less pronounced in dark-grown cultures, and did not occur in antioxidant-treated light-grown cultures. This suggests that a complex interplay between light, chloroplasts, ROS, and nuclear protein synthesis occurs during plant AL-PCD. The results of this study highlight the importance of taking into account the time-point at which cells are observed and whether the cells are light-grown and chloroplast-containing or not, for any study on plant AL-PCD, as it appears that chloroplasts can play a significant role in AL-PCD regulation.


Assuntos
Apoptose , Arabidopsis/citologia , Arabidopsis/metabolismo , Cloroplastos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas
17.
Psychol Rep ; 107(3): 833-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21323141

RESUMO

The VIA Survey of Character (VIA) is a self-report inventory designed to measure and assess 24 character strengths that are linked conceptually to six fundamental "virtues"--Wisdom and Knowledge, Courage, Humanity, Justice, Temperance, and Transcendence, as developed by Peterson and Seligman in 2004. Despite its popularity, the current presentation of the VIA is not easy to score; researchers must either use a limited online scoring facility or must use outdated scoring keys. This paper presents a full description of the scoring key.


Assuntos
Caráter , Inventário de Personalidade/estatística & dados numéricos , Humanos , Psicometria/estatística & dados numéricos
18.
JACC CardioOncol ; 6(1): 80-82, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38510298
19.
Eval Program Plann ; 74: 91-101, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30965218

RESUMO

Health systems are known for being complex. Yet, there is a paucity of evidence about programs that successfully develop competent frontline managers to navigate these complex systems. There is even less evidence about developing frontline managers in areas of contextual complexity such as geographically remote and isolated health services. This study used a customised management development program containing continuous quality improvement (CQI) approaches to determine whether additional levels of evaluation could provide evidence for program impact. Generalisability is limited by the small sample size; however, the findings suggest that continuous improvement approaches, such as action learning workplace-based CQI projects not only provide for real-world application of the manager's learning; they can potentially produce the type of data needed to conduct evaluations for organisational impact and cost-benefits. The case study contributes to the literature in an area where there is a scarcity of empirical research. Further, this study proposes a pragmatic method for using CQI approaches with existing management development programs to generate the type of data needed for multi-level evaluation.


Assuntos
Administração de Serviços de Saúde/normas , Avaliação de Programas e Projetos de Saúde/métodos , Melhoria de Qualidade/organização & administração , Serviços de Saúde Rural/organização & administração , Gestão da Qualidade Total/organização & administração , Austrália , Humanos , Estudos de Casos Organizacionais , Melhoria de Qualidade/normas , Serviços de Saúde Rural/normas
20.
Plant Sci ; 260: 50-59, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28554474

RESUMO

The protoplast retracts during apoptosis-like programmed cell death (AL-PCD) and, if this retraction is an active component of AL-PCD, it should be used as a defining feature for this type of programmed cell death. We used an array of pharmacological and genetic tools to test if the rates of protoplast retraction in cells undergoing AL-PCD can be modulated. Disturbing calcium flux signalling, ATP synthesis and mitochondrial permeability transition all inhibited protoplast retraction and often also the execution of the death programme. Protoplast retraction can precede loss of plasma membrane integrity and cell death can be interrupted after the protoplast retraction had already occurred. Blocking calcium influx inhibited the protoplast retraction, reduced DNA fragmentation and delayed death induced by AL-PCD associated stresses. At higher levels of stress, where cell death occurs without protoplast retraction, blocking calcium flux had no effect on the death process. The results therefore strongly suggest that retraction of the protoplast is an active biological process dependent on an early Ca2+-mediated trigger rather than cellular disintegration due to plasma membrane damage. Therefore this morphologically distinct cell type is a quantifiable feature, and consequently, reporter of AL-PCD.


Assuntos
Cálcio/metabolismo , Protoplastos/metabolismo , Transdução de Sinais/fisiologia , Morte Celular/genética , Morte Celular/fisiologia , Fragmentação do DNA , Necrose/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais/genética
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