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1.
J Fam Nurs ; 30(2): 174-184, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38528681

RESUMO

Family members' experience of integrating chronic illnesses or chronic conditions into family life is valuable information for health care professionals, such as nurses, to understand, improve, and adjust the care provided to families of chronically ill patients. Furthermore, the assessment of the experience of integrating chronic illness into family life can support family nursing interventions and reduce suffering. This study aimed to adapt and psychometrically test a new Likert-type questionnaire on the experience of integrating pediatric chronic illness into family life (EICI-FLQ) in two European samples. A sample of 164 primary caregivers of children/adolescents with chronic illnesses/conditions in Iceland and another sample of 237 primary caregivers with children/adolescents with chronic illnesses/conditions in Portugal completed the online questionnaire. Exploratory factor analysis of the Icelandic sample yielded support for a one-factor solution with acceptable internal reliability (Cronbach's α = .866). Confirmatory factor analysis of the one-factor structure in the Portuguese sample indicated good model fit and similar internal reliability (Cronbach's α = .838). This instrument has good psychometric characteristics and is a promising tool for measuring the experience of integrating pediatric chronic illness into family life in clinical and research settings.


Assuntos
Cuidadores , Psicometria , Humanos , Masculino , Feminino , Doença Crônica/psicologia , Inquéritos e Questionários/normas , Criança , Adulto , Portugal , Reprodutibilidade dos Testes , Pessoa de Meia-Idade , Adolescente , Islândia , Cuidadores/psicologia , Análise Fatorial , Família/psicologia , Pré-Escolar , Enfermagem Familiar/normas
2.
J Fam Nurs ; : 10748407241226955, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284366

RESUMO

Illness beliefs have a role in the adaptation, coping, well-being, healing, and recovery in families of children/adolescents with chronic illness. The assessment of family illness beliefs can support family nursing interventions that address the suffering of family members when illness arises. The purpose of this study was to translate, cross-culturally adapt, and psychometrically test the Portuguese version of the Iceland-Family Illness Beliefs Questionnaire. A sample of 237 parents of children/adolescents who experienced chronic health conditions completed the online questionnaire. The original factor model was tested through confirmatory factorial analysis. The results showed satisfactory model fit indices (χ2/gl = 3.004; comparative fit index [CFI] = 0.90; root mean square error of approximation [RMSEA] = 0.092) and internal consistency (Cronbach's α = 0.74). The instrument showed good psychometric characteristics of validity and reliability, suggesting it may be useful in the assessment of illness beliefs in families experiencing a pediatric chronic illness.

3.
J Pediatr Nurs ; 75: e34-e41, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38216349

RESUMO

PURPOSE: This study aimed to describe the perception of parents of children/adolescents with chronic conditions of their quality of life and family functioning during the COVID-19 pandemic and explore how the COVID-19 pandemic affected family management of children/adolescents' chronic conditions. DESIGN AND METHODS: A total of 237 parents of children/adolescents with chronic conditions participated in this cross-sectional study. Data were collected through an online questionnaire using the Paediatric Quality of Life Inventory™ Family Impact Module and an open-ended question about the impact of the pandemic on the family management of the paediatric chronic condition. RESULTS: The Total Score of PedsQL™ FIM was slightly higher than the midpoint of the scale (M = 60.27; SD = 19.04), and the impact of the pandemic on the family's management of the chronic condition was perceived by 30% of parents as high or moderate. Statistically significant differences were found between parents who reported a high or moderate impact of the pandemic and those reporting little or no impact of the pandemic regarding parental quality of life and family functioning (t (233) = 8.13, p = .00, Cohen's d = 1.14). Two themes emerged from the analysis of the open-ended question: Impact on the child/adolescent and Impact on the family. CONCLUSIONS: Parents of children/adolescents with chronic conditions reported an average quality of life, and the COVID-19 pandemic significantly impacted the family management of chronic conditions. PRACTICE IMPLICATIONS: These results highlight the importance of developing interventions to support families in complex situations and contexts, targeting family functioning, family quality of life, and emotional management.


Assuntos
COVID-19 , Qualidade de Vida , Adolescente , Criança , Humanos , Qualidade de Vida/psicologia , Pandemias , Estudos Transversais , Reprodutibilidade dos Testes , COVID-19/epidemiologia , Pais/psicologia , Doença Crônica
4.
J Spec Pediatr Nurs ; 28(3): e12406, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031356

RESUMO

PURPOSE: This study aims to assess the psychometric properties of the European Portuguese version of the Pediatric Quality of Life Inventory™ Family Impact Module in parents of children/adolescents with chronic health conditions. DESIGN AND METHODS: The European Portuguese version of the Pediatric Quality of Life Inventory™ Family Impact Module was administered to 237 parents of children/adolescents with chronic disease and/or chronic disorder. Participants were recruited from the day hospital and/or outpatient services of four hospitals in Northern Portugal, the majority being mothers (87.3%) aged between 31 and 50 years (86.9%). The questionnaire was administered online through the REDCap platform. The hierarchical factor model of the Pediatric Quality of Life Inventory™ Family Impact Module proposed by Varni and colleagues was tested. RESULTS: Confirmatory Factor Analysis indicated good model fit, with the following indices (χ2 /gL = 2.19; comparative fit index [CFI] = 0.90;  root mean square error of approximation [RMSEA] = 0.07 immune cell [IC] 90% = 0.06-0.07). Internal consistency values were high (parent quality of life subtotal, α = .96; family functioning subtotal, α = .92; total score, α = .96). PRACTICE IMPLICATIONS: The European Portuguese version of the PedsQL™ FIM is a reliable and valid measurement tool for nurses to assess the impact of the child/adolescent chronic conditions on family's quality of life and to develop interventions to improve their well-being.


Assuntos
Qualidade de Vida , Feminino , Adolescente , Criança , Humanos , Adulto , Pessoa de Meia-Idade , Portugal , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários , Doença Crônica
5.
Artigo em Inglês | MEDLINE | ID: mdl-36674081

RESUMO

Although many instruments are used to assess the families of people with diabetes, their measurement properties have not been systematically reviewed. We aimed to identify and evaluate the psychometric properties of the instruments used to assess family functioning in adults with diabetes. METHODS: A systematic literature review, according to the JBI systematic reviews of measurement properties, was conducted using different databases, including gray literature. PROSPERO registration number: CRD42021239733. Two independent reviewers searched, screened, and assessed the risk of bias among the articles according to the COSMIN methodology. The quality of each included instrument was assessed using the updated criteria for good measurement properties. RESULTS: Eighty-one studies were included, and thirty-one eligible instruments were identified. The psychometric properties frequently assessed were structural validity, internal consistency, and construct validity. CONCLUSIONS: Although 31 instruments were included, none of their psychometric properties were scored as "very good". From the instruments scored as adequate on development and content validity, five stood out for their quality appraisal.. The development of new instruments is not recommended. More studies should be conducted on the existing instruments to assess the less commonly evaluated psychometric properties. Using valid instruments to develop and evaluate interventions is essential to promote health literacy and the effectiveness of diabetes management.


Assuntos
Diabetes Mellitus , Letramento em Saúde , Adulto , Humanos , Promoção da Saúde , Psicometria , Reprodutibilidade dos Testes
6.
Ann Oper Res ; : 1-27, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36597501

RESUMO

Given the increasingly significant role of small and medium-sized enterprises (SMEs) in the global economy and the ever more competitive markets in which these companies operate, SMEs' ability to adopt artificial intelligence (AI) technologies is of utmost importance. Due to constantly evolving social, environmental, and technological scenarios, the managers of these firms must increasingly focus on incorporating new tools such as AI into SME operations in order to enjoy their benefits. However, the subjectivity and complexity of this adaptation process makes integrated analyses of key factors challenging. The present study sought to develop a multi-criteria decision-support system that applies cognitive mapping and the decision-making trial and evaluation laboratory technique in a neutrosophic context. The main objective is to overcome the limitations of previous studies and models by structuring the decision problem and identifying and understanding which factors should be central to adaptation initiative analyses. A panel of experts in AI were recruited to facilitate the construction of an analysis system that takes into account indeterminacy in decision-making processes. The results were validated by both the panel members and project managers at COTEC Portugal-a leading think-and-action network that seeks to advance technology diffusion and business innovation cooperation. The proposed system's practical implications and benefits are also analyzed.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36612569

RESUMO

The support from nurses perceived by family members of children with chronic conditions has been shown to be a protective factor at different levels in a family's health. As such, nurses need to have instruments that assess this perception to increase the quality of the care provided to those families. This methodological study aimed to analyze the psychometric properties of the Portuguese translation of the Iceland-Family Perceived Support Questionnaire (ICE-FPSQ) in parents of children/adolescents with chronic conditions. The ICE-FPSQ was administered to 237 parents recruited from the day hospital and outpatient services of four hospitals in Northern Portugal. Cronbach's alpha reliability coefficients for the Total Scale, Cognitive Support, and Emotional Support subscales were excellent (α = 0.96, α = 0.93, α = 0.96, respectively). Reasonable fit indexes were found by confirmatory factor analysis (χ2/df = 2.799; CFI = 0.960; PCFI = 0.791, and RMSEA = 0.087), indicating a good model fit to the original structure. The ICE-FPSQ is a valid and reliable instrument to measure perceived support.


Assuntos
Psicometria , Humanos , Criança , Adolescente , Portugal , Islândia , Reprodutibilidade dos Testes , Doença Crônica , Inquéritos e Questionários
8.
Adv Colloid Interface Sci ; 284: 102230, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32961420

RESUMO

The use of invasive medical devices is becoming more common nowadays, with catheters representing one of the most used medical devices. However, there is a risk of infection associated with the use of these devices, since they are made of materials that are prone to bacterial adhesion with biofilm formation, often requiring catheter removal as the only therapeutic option. Catheter-related urinary tract infections (CAUTIs) and central line-associated bloodstream infections (CLABSIs) are among the most common causes of healthcare-associated infections (HAIs) worldwide while endotracheal intubation is responsible for ventilator-associated pneumonia (VAP). Therefore, to avoid the use of biocides due to the potential risk of bacterial resistance development, antifouling strategies aiming at the prevention of bacterial adherence and colonization of catheter surfaces represent important alternative measures. This review is focused on the main strategies that are able to modify the physical or chemical properties of biomaterials, leading to the creation of antiadhesive surfaces. The most promising approaches include coating the surfaces with hydrophilic polymers, such as poly(ethylene glycol) (PEG), poly(acrylamide) and poly(acrylates), betaine-based zwitterionic polymers and amphiphilic polymers or the use of bulk-modified poly(urethanes). Natural polysaccharides and its modifications with heparin, have also been used to improve hemocompatibility. Recently developed bioinspired techniques yielding very promising results in the prevention of bacterial adhesion and colonization of surfaces include slippery liquid-infused porous surfaces (SLIPS) based on the superhydrophilic rim of the pitcher plant and the Sharklet topography inspired by the shark skin, which are potential candidates as surface-modifying approaches for biomedical devices. Concerning the potential application of most of these strategies in catheters, more in vivo studies and clinical trials are needed to assure their efficacy and safety for possible future use.


Assuntos
Incrustação Biológica/prevenção & controle , Infecções Relacionadas a Cateter/prevenção & controle , Animais , Aderência Bacteriana/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Infecções Relacionadas a Cateter/microbiologia , Humanos
9.
Breast Cancer ; 26(3): 397-405, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30535581

RESUMO

BACKGROUND: Few studies related to hereditary breast and ovarian cancer syndrome (HBOC) have been conducted in Brazil, and they are restricted to only small areas of the country. Here, we report the mutation profile of BRCA1/2, CHEK2 and TP53 genes in a cohort from Minas Gerais state. METHODS: These genes from 44 patients at high risk for HBOC were screened through high-resolution melting and/or sequencing. The pathogenicity of the alterations was checked using ClinVar database and bioinformatics programs. RESULTS: In BRCA genes we identified 46 variants, 38 without clinical significance and 8 pathogenic mutations including a new pathogenic mutation in BRCA1 gene (c.4688_4694delACCTGGAinsG). The most prevalent pathogenic mutation was c.4829_4830delTG, in the BRCA2 gene. This mutation was not described in the Brazilian population up to now and in this study, it was described with a prevalence of 6.8%. The p.R337H mutation in TP53 gene was found in one patient clinically diagnosed as HBOC and without clinical criteria for Li-Fraumeni syndrome. In CHEK2 gene, the undescribed variant c.485A > G was found and it presents as probably pathogenic through in silico analyses. Pathogenic mutations were found in 29.5% of the patients, 11.3% in BRCA1, 15.9% in BRCA2 and 2.3% in TP53 gene. CONCLUSIONS: Brazilian population is one of the most heterogeneous in the world and the mutational profile knowledge of genes related to HBOC from different regions can contribute to the definition of more cost-effective strategies for the prevention, identification and treatment of cancer.


Assuntos
Predisposição Genética para Doença/genética , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Adulto , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Brasil , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quinase do Ponto de Checagem 2/genética , Estudos de Coortes , Feminino , Síndrome Hereditária de Câncer de Mama e Ovário/patologia , Humanos , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Proteína Supressora de Tumor p53/genética
10.
Fam Cancer ; 15(2): 173-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26666763

RESUMO

The aim of this study was to evaluate the profile of BRCA1 mutations among cancer-affected Brazilian women from the Midwest region of Minas Gerais state with clearly defined risk factors for hereditary breast and ovarian cancer (HBOC) syndrome. In this Brazilian region, the first Center for Hereditary Cancer Control began operation in 2011, and 90% of patients receive assistance from the public health service. Eighteen patients at high risk for HBOC were subjected to molecular analysis. Primers were designed for 22 coding exons of the gene; DNA was extracted; and real-time PCR followed by high-resolution melting reaction was performed. The amplicons were sequenced to confirm the identified profiles. Only exon 11 was directly sequenced due its length. Multiplex ligation-dependent probe amplification (MLPA) was performed for those patients in whom no pathogenic mutations were found. Among the 14 alterations identified in this study, the c.5263_5264insC pathogenic mutation was present in two patients (11.1%). Four alterations showed no clinical relevance; one exhibited inconclusive clinical relevance according to the examined databases; and eight alterations presented a divergent classification between the databases. No deletions or duplications were found using the MLPA technique. The HRM methodology was highly sensitive in identifying variants in the BRCA1 gene and can dramatically reduce the amount of sequencing required to identify germline mutations in BRCA genes, enabling cheaper tests and increasing their availability to Brazilian women assisted by the public health service.


Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Testes Genéticos/métodos , Neoplasias Ovarianas/genética , Adulto , Idoso , Brasil , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex
11.
Medicine (Baltimore) ; 94(33): e1403, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26287431

RESUMO

To estimate the association between 2 markers for atherosclerosis, measurements of carotid artery intima-media thickness (IMT) and of peripheral arterial tonometry (PAT), and to evaluate the role of traditional cardiovascular risk factors in this association.We applied the 2 diagnostic tests to 588 participants from the ELSA-Brazil longitudinal study cohort. The PAT measurements, obtained with the EndoPAT2000, were the reactive hyperemia index (RHI), the Framingham RHI (F-RHI), and the mean basal pulse amplitude (BPA). We used the mean of the mean scores of carotid IMT of the distal layers of the left and right common carotids obtained by ultrasonography after 3 cardiac cycles. We used linear regression and the Spearman correlation coefficient to test the relationship between the 2 markers, and multiple linear regressions to exam the relationship between the RHI/F-RHI scores and the mean BPA and IMT scores after adjusting for cardiovascular risk factors.In the multivariate analysis, RHI (but not F-RHI) was positively correlated with the mean of the means of the IMT values after adjusting for sex and risk factors connected with both measures (ß = 0.05, P = 0.02). Mean BPA did not remain significantly associated with IMT after adjusting for common risk factors.We found that the higher the IMT (or the worse the IMT), the higher the RHI (or the better the endothelial function). F-RHI was not associated with IMT. These 2 results are against the direction that one would expect and may imply that digital endothelial function (RHI and F-RHI) and IMT correspond to distinct and independent stages of the complex atherosclerosis process and represent different pathways in the disease's progression. Therefore, IMT and PAT measures may be considered complementary and not interchangeable.


Assuntos
Aterosclerose/diagnóstico , Espessura Intima-Media Carotídea , Manometria/métodos , Adulto , Aterosclerose/epidemiologia , Aterosclerose/fisiopatologia , Brasil/epidemiologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiopatologia , Feminino , Humanos , Hiperemia/diagnóstico , Hiperemia/etiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso/métodos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco
12.
Front Immunol ; 4: 452, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24379814

RESUMO

Inflammatory reactions are believed to be triggered by innate signals and have a major protective role by recruiting innate immunity cells, favoring lymphocyte activation and differentiation, and thus contributing to the sequestration and elimination of the injurious stimuli. Although certain lymphocyte types such as TH17 cells co-participate in inflammatory reactions, their generation from the naïve pool requires the pre-existence of an inflammatory milieu. In this context, inflammation is always regarded as beginning with an innate response that may be eventually perpetuated and amplified by certain lymphocyte types. In contrast, we here show that even in sterile immunizations or in MyD88-deficient mice, CD8 T cells produce a burst of pro-inflammatory cytokines and chemokines. These functions follow opposite rules to the classic CD8 effector functions since they are generated prior to cell expansion and decline before antigen elimination. As few as 56 CD8(+) inflammatory effector cells in a lymph node can mobilize 10(7) cells in 24 h, including lymphocytes, natural killer cells, and several accessory cell types involved in inflammatory reactions. Thus, although inflammation modulates cognate responses, CD8 cognate responses also initiate local inflammatory reactions.

13.
J Exp Med ; 209(8): 1401-8, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-22778388

RESUMO

Thymus transplants can correct deficiencies of the thymus epithelium caused by the complete DiGeorge syndrome or FOXN1 mutations. However, thymus transplants were never used to correct T cell-intrinsic deficiencies because it is generally believed that thymocytes have short intrinsic lifespans. This notion is based on thymus transplantation experiments where it was shown that thymus-resident cells were rapidly replaced by progenitors originating in the bone marrow. In contrast, here we show that neonatal thymi transplanted into interleukin 7 receptor-deficient hosts harbor populations with extensive capacity to self-renew, and maintain continuous thymocyte generation and export. These thymus transplants reconstitute the full diversity of peripheral T cell repertoires one month after surgery, which is the earliest time point studied. Moreover, transplantation experiments performed across major histocompatibility barriers show that allogeneic transplanted thymi are not rejected, and allogeneic cells do not induce graft-versus-host disease; transplants induced partial or total protection to infection. These results challenge the current dogma that thymocytes cannot self-renew, and indicate a potential use of neonatal thymus transplants to correct T cell-intrinsic deficiencies. Finally, as found with mature T cells, they show that thymocyte survival is determined by the competition between incoming progenitors and resident cells.


Assuntos
Células da Medula Óssea/citologia , Timócitos/citologia , Timo/transplante , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/imunologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Receptores de Interleucina-7/deficiência , Receptores de Interleucina-7/imunologia , Receptores de Interleucina-7/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Timócitos/imunologia , Timócitos/metabolismo , Timo/imunologia , Timo/metabolismo , Transplante Homólogo
14.
J Immunol ; 184(5): 2272-80, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20130214

RESUMO

Little is known about target organ-infiltrating NK cells in type 1 diabetes and other autoimmune diseases. In this study, we identified NK cells with a unique phenotype in the pancreas of NOD mice. Pancreatic NK cells, localized to the endocrine and exocrine parts, were present before T cells during disease development and did not require T cells for their infiltration. Furthermore, NK cells, or NK cell precursors, from the spleen could traffic to the pancreas, where they displayed the pancreatic phenotype. Pancreatic NK cells from other mouse strains shared phenotypic characteristics with pancreatic NK cells from NOD mice, but displayed less surface killer cell lectin-like receptor G1, a marker for mature NK cells that have undergone proliferation, and also did not proliferate to the same extent. A subset of NOD mouse pancreatic NK cells produced IFN-gamma spontaneously, suggesting ongoing effector responses. However, most NOD mouse pancreatic NK cells were hyporesponsive compared with spleen NK cells, as reflected by diminished cytokine secretion and a lower capacity to degranulate. Interestingly, such hyporesponsiveness was not seen in pancreatic NK cells from the nonautoimmune strain C57BL/6, suggesting that this feature is not a general property of pancreatic NK cells. Based on our data, we propose that NK cells are sentinel cells in a normal pancreas. We further speculate that during inflammation, pancreatic NK cells initially mediate proinflammatory effector functions, potentially contributing to organ-specific autoimmunity, but later become hyporesponsive because of exhaustion or regulation.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Ilhotas Pancreáticas/imunologia , Células Matadoras Naturais/imunologia , Pâncreas Exócrino/imunologia , Animais , Proliferação de Células , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Feminino , Citometria de Fluxo , Imunofluorescência , Imunofenotipagem , Ilhotas Pancreáticas/metabolismo , Células Matadoras Naturais/metabolismo , Antígeno de Macrófago 1/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Pâncreas Exócrino/metabolismo , Receptores de Interleucina-2/deficiência , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/imunologia , Especificidade da Espécie , Linfócitos T/imunologia , Linfócitos T/metabolismo , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo
15.
J Virol ; 83(22): 11795-807, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19726518

RESUMO

To evaluate the impact of immunodominance on CD8 T-cell properties, we compared the functional properties of dominant and subdominant populations in the response to lymphocytic choriomeningitis virus (LCMV). To improve functional discrimination, in addition to the usual tests of phenotype and function, we used a sensitive technique that allows the screening of all CD8 effector genes simultaneously in single cells. Surprisingly, these methods failed to reveal a major impact of clonal dominance in CD8 properties throughout the response. Aiming to increase clonal dominance, we examined high-frequency transferred P14 T-cell receptor transgenic (TCR Tg) cells. Under these conditions LCMV is cleared faster, and accordingly we found an accelerated response. However, when Tg and endogenous cells were studied in the same mice, where they should be subjected to the same antigen load, they showed overlapping properties, and the presence of P14 cells did not modify endogenous responses to other LCMV epitopes or a perturbed immunodominance hierarchy in the memory phase. Using allotype-labeled Tg cells, we found that during acute infection up to 80% downregulated their TCR and were undetectable by tetramer binding, and that tetramer-negative and tetramer-positive cells had very different features. Since Tg cells are not available to evaluate immune responses in humans and, in many cases, are not available from the mouse, the tetramer-based evaluation of early immune responses in most situations of high viremia may be incomplete and biased.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Epitopos de Linfócito T/imunologia , Coriomeningite Linfocítica/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Animais , Regulação da Expressão Gênica/imunologia , Memória Imunológica/imunologia , Camundongos , Receptores de Antígenos de Linfócitos T/imunologia , Latência Viral
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