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1.
Biomacromolecules ; 25(5): 3076-3086, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38634234

RESUMO

Despite the wide range of analytical tools available for the characterization of cellulose, the in-depth characterization of inhomogeneous, layered cellulose fiber structures remains a challenge. When treating fibers or spinning man-made fibers, the question always arises as to whether the changes in the fiber structure affect only the surface or the entire fiber. Here, we developed an analysis tool based on the sequential limited dissolution of cellulose fiber layers. The method can reveal potential differences in fiber properties along the cross-sectional profile of natural or man-made cellulose fibers. In this analytical approach, carbonyl groups are labeled with a carbonyl selective fluorescence label (CCOA), after which thin fiber layers are sequentially dissolved with the solvent system DMAc/LiCl (9% w/v) and analyzed with size exclusion chromatography coupled with light scattering and fluorescence detection. The analysis of these fractions allowed for the recording of the changes in the chemical structure across the layers, resulting in a detailed cross-sectional profile of the different functionalities and molecular weight distributions. The method was optimized and tested in practice with LPMO (lytic polysaccharide monooxygenase)-treated cotton fibers, where it revealed the depth of fiber modification by the enzyme.


Assuntos
Celulose , Celulose/química , Fibra de Algodão , Cromatografia em Gel/métodos
2.
J Fish Biol ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733293

RESUMO

Individuals must reproduce to survive and thrive from generation to generation. In fish, the fecundity of individuals and estimates of total reproductive output are critical for evaluating reproductive success and understanding population dynamics. Estimating fecundity is an onerous task; therefore, many populations lack contemporary estimates of fecundity and size-fecundity relationships. However, reproductive dynamics are not static in time; therefore, it is important to develop contemporary fecundity estimates to better inform conservation and management action. To highlight the importance of contemporary fecundity estimates, we examined the fecundity of southern Gulf of St. Lawrence (sGSL) spring and fall spawning Atlantic herring in 2022, developed size-fecundity models, and compared these to historical fecundity estimates and models. Our results suggest that the average fecundity of sGSL spring and fall herring has undergone a substantial temporal decline of approximately 47% and 58%, respectively, since the 1970s and 1980s. The size-fecundity relationships for fall spawning herring have shifted, with fish of a given size exhibiting lower fecundity in 2022 compared to the 1970s. Alternatively, the size-fecundity relationships for spring spawning herring have remained relatively static. Furthermore, simulations highlighted a substantial reduction in potential reproductive output in 2022 compared to 1970 of approximately 32% and 68% for spring and fall spawners, respectively, based on a fixed number of mature females, which may have negative implications for stock rebuilding. Overall, our study provides support for periodic estimates of fecundity in fish populations to better understand temporal changes in reproductive and population dynamics.

3.
J Community Health Nurs ; 41(1): 21-29, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37937801

RESUMO

PURPOSE: The purpose of this research study was to determine the effectiveness of an innovative online COVID-19 educational module among community health nursing students. DESIGN: Mixed-methods study. METHODS: The sample (N = 86) consisted of prelicensure and postlicensure community health nursing students, who completed a pretest, COVID-19 educational intervention, and posttest. FINDINGS: The majority of participants' scores increased from pretest to posttest, and most participants strongly agreed that the COVID-19 educational module was effective. Strategies to address vaccine hesitancy, information learned and found most helpful, and plans for application and utilization of this knowledge were revealed. CONCLUSIONS: An online COVID-19 community health nursing educational intervention was effective at improving participants' knowledge, confidence, and attitudes regarding COVID-19. CLINICAL EVIDENCE: Online COVID-19 community health nursing education was an effective strategy for increasing preparation for this pandemic and the format can be useful to utilize for future public health emergencies.


Assuntos
COVID-19 , Enfermagem em Saúde Comunitária , Bacharelado em Enfermagem , Estudantes de Enfermagem , Humanos , COVID-19/prevenção & controle , Bacharelado em Enfermagem/métodos , Conhecimentos, Atitudes e Prática em Saúde
4.
J Community Health Nurs ; 39(2): 107-120, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603871

RESUMO

PURPOSE: To evaluate the effectiveness of an online human trafficking awareness program for healthcare providers. DESIGN: Mixed-methods study. METHODS: Sample (N=141) consisted of community health nursing students, who completed a pretest, watched one three-minute video a day for 20 days, and completed a posttest. FINDINGS: Participants indicated their knowledge of human trafficking increased, attitudes toward victims improved, and competence and confidence engaging with victims increased. Satisfaction with program, and information utilization plans for practice were revealed. CONCLUSIONS: Human trafficking awareness program was effective in increasing participants' knowledge, competence and confidence, and improving attitudes. CLINICAL EVIDENCE: Educational intervention is a strategy to improve students' knowledge of human trafficking.


Assuntos
Enfermagem em Saúde Comunitária , Tráfico de Pessoas , Estudantes de Enfermagem , Conhecimentos, Atitudes e Prática em Saúde , Tráfico de Pessoas/prevenção & controle , Humanos
5.
Nurs Educ Perspect ; 42(1): 46-48, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32028377

RESUMO

ABSTRACT: Public health departments exemplify interprofessional collaboration. Nursing and public health education students are required to complete practicum hours or an internship respectively in community health, yet placements at health departments are limited and competitive. This study evaluated the effects of an interprofessional education intervention on community health nursing and health education students' current interprofessional awareness and understanding, and intent to collaborate interprofessionally. Results showed that the majority of participants felt that their interprofessional awareness, understanding, and intent to collaborate increased. This intervention helped bring an example of the health department experience to students and demonstrate its interprofessional nature.


Assuntos
Internato e Residência , Saúde Pública , Comportamento Cooperativo , Humanos , Relações Interprofissionais , Inquéritos e Questionários
6.
J Community Health Nurs ; 38(4): 244-252, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34787040

RESUMO

Purpose: To evaluate the effectiveness of a community/public health nursing virtual simulation. Design: Mixed-methods study. Methods: Sample (N = 121) consisted of community health nursing students, who completed a pretest, virtual simulation, posttest, and satisfaction and self-confidence in learning scale.Findings: Majority of participants' scores increased from pretest to posttest, and most participants agreed or strongly agreed with statements regarding satisfaction and self-confidence in learning; material learned and found most helpful, as well as knowledge application/utilization plans for practice were revealed. Conclusions: Community/public health nursing virtual simulation was effective at increasing participants' knowledge, and satisfaction and self-confidence in learning.Clinical Evidence: Virtual simulation is a strategy to improve students' knowledge of community/public health nursing.


Assuntos
Enfermagem em Saúde Comunitária , Bacharelado em Enfermagem , Estudantes de Enfermagem , Competência Clínica , Humanos , Enfermagem em Saúde Pública , Autoimagem
7.
J Community Health Nurs ; 38(4): 209-220, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34787043

RESUMO

PURPOSE: To evaluate the effectiveness of a virtual interprofessional collaboration in public health educational intervention. DESIGN: Mixed-methods study. METHODS: Sample (N =171) consisted of community health nursing students, who completed an assessment after watching six videos, illustrating how various disciplines collaborate in a public health department. FINDINGS: Participants felt their interprofessional awareness, understanding, and collaboration intention increased; clarified discipline misconceptions, and application/utilization plans for this knowledge in practice were revealed. CONCLUSIONS: Interprofessional collaboration in public health educational intervention was effective in increasing participants' interprofessional awareness, understanding, and intent to collaborate. CLINICAL EVIDENCE: Educational intervention is a strategy to improve students' knowledge of interprofessional collaboration in public health.


Assuntos
Enfermagem em Saúde Comunitária , Estudantes de Enfermagem , Comportamento Cooperativo , Humanos , Relações Interprofissionais , Estudantes
8.
Holist Nurs Pract ; 35(6): 300-305, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34647911

RESUMO

Complementary and alternative medicine therapies can be used as adjuvant or preventive therapy, and have newer applications: cryotherapy, halotherapy, floatation therapy, and compression therapy. Nurse practitioners need to know about these therapies and their applicability to patient populations. Appropriate integration of these therapies is part of holistic care, which they strive to provide.


Assuntos
Terapias Complementares , Humanos
9.
Immunol Invest ; 49(7): 726-743, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32299258

RESUMO

Background: T cells present in chronic inflammatory tissues such as nasal polyps (from chronic rhinosinusitis patients) have been demonstrated to be hypo-responsive to activation via the TCR, similar to tumor-specific T cells in multiple different human tumor microenvironments. While immunosuppressive exosomes have been known to contribute to the failure of the tumor-associated T cells to respond optimally to activation stimuli, it is not known whether they play a similar role in chronic inflammatory microenvironments. In the current study, we investigate whether exosomes derived from chronic inflammatory microenvironments contribute to the immune suppression of T cells. Methods: Exosomes were isolated by ultracentrifugation and characterized by size and composition using nanoparticle tracking analysis, scanning electron microscopy, antibody arrays and flow exometry. Immunosuppressive ability of the exosomes was measured by quantifying its effect on activation of T cells, using nuclear translocation of NFκB as an activation endpoint. Results: Exosomes were isolated and characterized from two different types of chronic inflammatory tissues - nasal polyps from chronic rhinosinusitis patients and synovial fluid from rheumatoid arthritis patients. These exosomes arrest the activation of T cells stimulated via the TCR. This immune suppression, like that which is seen in tumor microenvironments, is dependent in part upon a lipid, ganglioside GD3, which is expressed on the exosomal surface. Conclusion: Immunosuppressive exosomes present in non-malignant chronic inflammatory tissues represent a new T cell checkpoint, and potentially represent a novel therapeutic target to enhance the response to current therapies and prevent disease recurrences.


Assuntos
Microambiente Celular/imunologia , Exossomos/metabolismo , Imunomodulação , Inflamação/etiologia , Inflamação/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Artrite/etiologia , Artrite/metabolismo , Biomarcadores , Doença Crônica , Suscetibilidade a Doenças , Exossomos/ultraestrutura , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/ultraestrutura , Humanos , Imuno-Histoquímica , Imunofenotipagem , Inflamação/patologia , Metabolismo dos Lipídeos , Ativação Linfocitária/imunologia , NF-kappa B/metabolismo , Pólipos Nasais/etiologia , Pólipos Nasais/metabolismo , Pólipos Nasais/patologia , Transporte Proteico , Transdução de Sinais , Líquido Sinovial/metabolismo
10.
J Community Health ; 45(2): 407-411, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31612367

RESUMO

Adolescent and young adult females are at increased risk for STDs/STIs and their complications. It is imperative that the sexual health education provided to this vulnerable population is effective. This mixed methods study assessed the impact of an online educational intervention on knowledge of sexual health and STDs/STIs, and impact on behavioral intent among sexually active, young adult females 18-22 years of age. Results showed that the online educational intervention was effective. Scores increased from pretest to posttest and responses included what participants learned and found most helpful, and changes they plan to make as a result of the educational intervention.


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Saúde Sexual/educação , Adolescente , Adulto , Feminino , Humanos , Comportamento Sexual/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/prevenção & controle , Estudantes/estatística & dados numéricos , Adulto Jovem
11.
Exp Aging Res ; 46(4): 291-310, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32314669

RESUMO

BACKGROUND: Whether bilingualism can improve aspects of cognitive function in late adulthood is hotly debated. A few limited studies have reported that bilingualism may provide a limited buffer against age-related cognitive decline; however, others have not. The present study furthered this inquiry by analyzing the combined effects of age and language experience upon executive function in a geographically diverse online sample. METHODS: Amazon Mechanical Turk was used to recruit a sample of younger (YA) and older adults (OA) from 24 countries. A total of 81 monolingual participants (YA = 37; OA = 44) and 82 bilingual/multilingual participants (YA = 43; OA = 39) completed task-pure executive function assessments of inhibition, memory updating, and attention switching. RESULTS: YAs performed better than OAs on both the inhibition and updating tasks. On the attention switching task, a greater switch cost occurred when participants had less time to process a stimulus cue. Notably, no effects of language (i.e., bilingualism) were significant: no main effects or interactions with aging were found for executive function performance. CONCLUSION: The results of the present study challenge the claim that extensive experience with multiple languages can be a reliably protective factor against some normative age-related declines in executive function.


Assuntos
Envelhecimento/psicologia , Disfunção Cognitiva/psicologia , Função Executiva , Multilinguismo , Adulto , Idoso , Atenção , Feminino , Humanos , Inibição Psicológica , Masculino , Memória , Pessoa de Meia-Idade , Adulto Jovem
12.
Nurs Educ Perspect ; 41(2): 112-114, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30747791

RESUMO

The transition between student and new nurse practitioner (NP) can be challenging. Survival guides given to student NPs may help ease the transition and make it a successful one. This study evaluates the effectiveness of survival guides in two student NP cohorts in the fall 2015 and fall 2016 semesters. Students completed a brief online survey at graduation, and three and six months after graduation. Results support the inclusion of survival guides in NP curricula as a creative way to positively support the transition from student to new NP and improve preparation for NP practice.


Assuntos
Educação em Enfermagem/organização & administração , Profissionais de Enfermagem/educação , Estudantes de Enfermagem/psicologia , Currículo , Humanos , Profissionais de Enfermagem/psicologia , Pesquisa em Educação em Enfermagem , Pesquisa em Avaliação de Enfermagem , Inquéritos e Questionários
13.
Nurs Educ Perspect ; 40(2): 110-112, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30095733

RESUMO

Students in health care today are very different than those of past generations. Health care education requires both innovation and creativity to meet the changing needs of students. Soft skills such as leadership, communication, nursing informatics, technology, and professionalism can sometimes be lost in pursuit of scientific knowledge. The purpose of this descriptive pilot study was to evaluate the effectiveness of a product designed to assist in the development of soft skills in a bachelor of science in nursing curriculum. This research did not support the additive value of this particular product but recommended further research at other curricular levels.


Assuntos
Bacharelado em Enfermagem , Estudantes de Enfermagem , Currículo , Humanos , Liderança , Pesquisa em Educação em Enfermagem , Projetos Piloto , Estudantes
14.
J Anim Ecol ; 87(1): 101-112, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28815647

RESUMO

Long-term individual-based datasets on host-pathogen systems are a rare and valuable resource for understanding the infectious disease dynamics in wildlife. A study of European badgers (Meles meles) naturally infected with bovine tuberculosis (bTB) at Woodchester Park in Gloucestershire (UK) has produced a unique dataset, facilitating investigation of a diverse range of epidemiological and ecological questions with implications for disease management. Since the 1970s, this badger population has been monitored with a systematic mark-recapture regime yielding a dataset of >15,000 captures of >3,000 individuals, providing detailed individual life-history, morphometric, genetic, reproductive and disease data. The annual prevalence of bTB in the Woodchester Park badger population exhibits no straightforward relationship with population density, and both the incidence and prevalence of Mycobacterium bovis show marked variation in space. The study has revealed phenotypic traits that are critical for understanding the social structure of badger populations along with mechanisms vital for understanding disease spread at different spatial resolutions. Woodchester-based studies have provided key insights into how host ecology can influence infection at different spatial and temporal scales. Specifically, it has revealed heterogeneity in epidemiological parameters; intrinsic and extrinsic factors affecting population dynamics; provided insights into senescence and individual life histories; and revealed consistent individual variation in foraging patterns, refuge use and social interactions. An improved understanding of ecological and epidemiological processes is imperative for effective disease management. Woodchester Park research has provided information of direct relevance to bTB management, and a better appreciation of the role of individual heterogeneity in disease transmission can contribute further in this regard. The Woodchester Park study system now offers a rare opportunity to seek a dynamic understanding of how individual-, group- and population-level processes interact. The wealth of existing data makes it possible to take a more integrative approach to examining how the consequences of individual heterogeneity scale to determine population-level pathogen dynamics and help advance our understanding of the ecological drivers of host-pathogen systems.


Assuntos
Mustelidae , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/transmissão , Animais , Bovinos , Inglaterra/epidemiologia , Incidência , Mycobacterium bovis/fisiologia , Densidade Demográfica , Dinâmica Populacional , Prevalência , Comportamento Social , Tuberculose Bovina/microbiologia
15.
Proc Biol Sci ; 284(1854)2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28469015

RESUMO

Kin selection theory predicts that animals should direct costly care where inclusive fitness gains are highest. Individuals may achieve this by directing care at closer relatives, yet evidence for such discrimination in vertebrates is equivocal. We investigated patterns of cooperative care in banded mongooses, where communal litters are raised by adult 'escorts' who form exclusive caring relationships with individual pups. We found no evidence that escorts and pups assort by parentage or relatedness. However, the time males spent escorting increased with increasing relatedness to the other group members, and to the pup they had paired with. Thus, we found no effect of relatedness in partner choice, but (in males) increasing helping effort with relatedness once partner choices had been made. Unexpectedly, the results showed clear assortment by sex, with female carers being more likely to tend to female pups, and male carers to male pups. This sex-specific assortment in helping behaviour has potential lifelong impacts on individual development and may impact the future size and composition of natal groups and dispersing cohorts. Where relatedness between helpers and recipients is already high, individuals may be better off choosing partners using other predictors of the costs and benefits of cooperation, without the need for possibly costly within-group kin discrimination.


Assuntos
Comportamento Cooperativo , Comportamento de Ajuda , Herpestidae/fisiologia , Animais , Feminino , Masculino
16.
J Anim Ecol ; 86(2): 285-295, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27973683

RESUMO

The manner in which patterns of variation and interactions among demographic rates contribute to population growth rate (λ) is key to understanding how animal populations will respond to changing climatic conditions. Migratory species are likely to be particularly sensitive to climatic conditions as they experience a range of different environments throughout their annual cycle. However, few studies have provided fully integrated demographic analyses of migratory populations in response to changing climatic conditions. Here, we employed integrated population models to demonstrate that the environmental conditions experienced during a short but critical period play a central role in the demography of a long-distance migrant, the light-bellied Brent goose (Branta bernicla hrota). Female survival was positively associated with June North Atlantic Oscillation (NAO) values, whereas male survival was not. In contrast, breeding productivity was negatively associated with June NAO, suggesting a trade-off between female survival and reproductive success. Both adult female and adult male survival showed low temporal variation, whereas there was high temporal variation in recruitment and breeding productivity. In addition, while annual population growth was positively correlated with annual breeding productivity, a sensitivity analysis revealed that population growth was most sensitive to changes in adult survival. Our results demonstrate that the environmental conditions experienced during a relatively short-time window at the start of the breeding season play a critical role in shaping the demography of a long-distant Arctic migrant. Crucially, different demographic rates responded in opposing directions to climatic variation, emphasising the need for integrated analysis of multiple demographic traits when understanding population dynamics.


Assuntos
Migração Animal , Gansos/fisiologia , Longevidade , Reprodução , Animais , Canadá , Meio Ambiente , Feminino , Masculino , Modelos Biológicos , Dinâmica Populacional
17.
Ecol Lett ; 19(4): 443-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26868206

RESUMO

Demographic buffering allows populations to persist by compensating for fluctuations in vital rates, including disease-induced mortality. Using long-term data on a badger (Meles meles Linnaeus, 1758) population naturally infected with Mycobacterium bovis, we built an integrated population model to quantify impacts of disease, density and environmental drivers on survival and recruitment. Badgers exhibit a slow life-history strategy, having high rates of adult survival with low variance, and low but variable rates of recruitment. Recruitment exhibited strong negative density-dependence, but was not influenced by disease, while adult survival was density independent but declined with increasing prevalence of diseased individuals. Given that reproductive success is not depressed by disease prevalence, density-dependent recruitment of cubs is likely to compensate for disease-induced mortality. This combination of slow life history and compensatory recruitment promotes the persistence of a naturally infected badger population and helps to explain the badger's role as a persistent reservoir of M. bovis.


Assuntos
Animais Selvagens/microbiologia , Mustelidae/microbiologia , Tuberculose/veterinária , Animais , Mycobacterium bovis/fisiologia , Densidade Demográfica , Prevalência , Tuberculose/epidemiologia , Tuberculose/mortalidade
18.
J Trauma Nurs ; 23(1): 3-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26745533

RESUMO

Compassion fatigue (CF) and burnout syndrome (BOS) are identified in trauma, emergency, and critical care nursing practices. The purpose of this qualitative study was to measure CF and BOS in a trauma team and allow them to share perceptions of related stress triggers and coping strategies. Surveys to measure CF and BOS and a focus group allowed a trauma team (12 practitioners) to share perceptions of related stress triggers and coping strategies. More than half scored at risk for CF and BOS. Stress triggers were described as situation (abuse, age of patient) versus injury-related. Personal coping mechanisms were most often reported. Both CF and BOS can be assessed with a simple survey tool. Strategies for developing a program culturally sensitive to CF and BOS are provided.


Assuntos
Esgotamento Profissional/epidemiologia , Fadiga de Compaixão/psicologia , Pesquisa Qualitativa , Inquéritos e Questionários , Ferimentos e Lesões/enfermagem , Adaptação Psicológica , Adulto , Esgotamento Profissional/psicologia , Fadiga de Compaixão/epidemiologia , Feminino , Humanos , Incidência , Masculino , Equipe de Enfermagem/organização & administração , Medição de Risco , Centros de Traumatologia
19.
Evol Appl ; 17(3): e13675, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38495946

RESUMO

Understanding how marine organisms adapt to local environments is crucial for predicting how populations will respond to global climate change. The genomic basis, environmental factors and evolutionary processes involved in local adaptation are however not well understood. Here we use Atlantic herring, an abundant, migratory and widely distributed marine fish with substantial genomic resources, as a model organism to evaluate local adaptation. We examined genomic variation and its correlation with environmental variables across a broad environmental gradient, for 15 spawning aggregations in Atlantic Canada and the United States. We then compared our results with available genomic data of northeast Atlantic populations. We confirmed that population structure lies in a fraction of the genome including likely adaptive genetic variants of functional importance. We discovered 10 highly differentiated genomic regions distributed across four chromosomes. Nine regions show strong association with seasonal reproduction. One region, corresponding to a known inversion on chromosome 12, underlies a latitudinal pattern discriminating populations north and south of a biogeographic transition zone on the Scotian Shelf. Genome-environment associations indicate that winter seawater temperature best correlates with the latitudinal pattern of this inversion. The variation at two so-called 'islands of divergence' related to seasonal reproduction appear to be private to the northwest Atlantic. Populations in the northwest and northeast Atlantic share variation at four of these divergent regions, simultaneously displaying significant diversity in haplotype composition at another four regions, which includes an undescribed structural variant approximately 7.7 Mb long on chromosome 8. Our results suggest that the timing and geographic location of spawning and early development may be under diverse selective pressures related to allelic fitness across environments. Our study highlights the role of genomic architecture, ancestral haplotypes and selection in maintaining adaptive divergence in species with large population sizes and presumably high gene flow.

20.
Cancer Immun ; 13: 14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23882159

RESUMO

Human memory T cells present in ovarian tumor ascites fluids fail to respond normally to stimulation via the T cell receptor (TCR). This immunosuppression is manifested by decreases in NF-κB and NFAT activation, IFN-γ production, and cell proliferation in response to TCR stimulation with immobilized antibodies to CD3 and CD28. The anergy of the tumor-associated T cells (TATs) is mediated by soluble factors present in ovarian tumor ascites fluids. The non-responsiveness of the T cells is quickly reversed when the cells are assayed in the absence of the ascites fluid, and is rapidly reestablished when a cell-free ascites fluid is added back to the T cells. Based upon the observed normal phosphorylation patterns of the TCR proximal signaling molecules, the inhibition of NF-κB, and NFAT activation in response to TCR stimulation, as well as the ability of the diacylglycerol analog PMA and the ionophore ionomycin to bypass the ascites fluid-induced TCR signaling arrest, the site of the arrest in the activation cascade appears to be at or just upstream of PLC-γ. An identical TCR signaling arrest pattern was observed when T cells derived from normal donor peripheral blood were incubated with either malignant or nonmalignant (cirrhotic) ascites fluids. The immunosuppressive activity of ascites fluids reported here suggests that soluble factors acting directly or indirectly upon T cells present within tumors contribute to the anergy that has previously been observed in T cells derived from malignant and nonmalignant inflammatory microenvironments. The soluble immunosuppressive factors represent potential therapeutic targets for ovarian cancer.


Assuntos
NF-kappa B/imunologia , Fatores de Transcrição NFATC/imunologia , Neoplasias Ovarianas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Ascite/imunologia , Ascite/patologia , Feminino , Humanos , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
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