Grandparent-grandchild relationships, generativity, subjective well-being and self-rated health of older people in Chile.

With increasing life expectancy, grandparents and grandchildren have more years available to share. Furthermore, with lower fertility rates and fewer grandchildren, relationships can be more frequent and profound. Intergenerational relationships are expected to be associated with older people's quality of life, especially in Latin American countries such as Chile, with high intergenerational co-residence and contact between generations. This research aims to analyze the associations between the characteristics of intergenerational relationships and grandparents' subjective well-being (Diener Scale and Satisfaction) and self-rated health. The novelty stems from including the structural characteristics of relationships with grandchildren (frequency of contact, closeness, and care), the activities they share (generativity), and the quality of relationships (ambivalence). This study is based on data from a specific face-to-face grandparenting survey conducted on a sample of 464 grandparents in January 2020. It is representative of older Chilean grandparents living in private dwellings. Multiple logistic and ordinary regression models were estimated using the Diener Scale, unique satisfaction question, and health self-perception. The results demonstrated that subjective well-being, but not self-rated health, was highly associated with the characteristics of intergenerational relationships, especially with the quality of relationships and with generative activities such as recreational activities and family identity. In conclusion, intergenerational relationships' quality and content are strongly associated with subjective well-being in old age, but not with health self-perception. Even in a Latin American country like Chile, with high co-residence and intergenerational contact, the variations in quality and generativity activities significantly explain the variations in subjective well-being. For this reason, policies for the promotion of well-being in older people must consider the family environment in which older people live, encompassing wider family networks, including grandchildren.

A longitudinal study monitoring the quality of life in a national cohort of older adults in Chile before and during the COVID-19 outbreak.

BACKGROUND: Confinement during the COVID-19 pandemic has placed great stress on older adults, which may be affecting their quality of life. Thus, this study aims to describe the changes in mental and physical health, isolation and loneliness, residence and socioeconomic resources in a national cohort of Chilean older adults before and during the COVID-19 outbreak. It also analyzes the changes in depressive symptoms by changes in the other quality of life indicators before and during the COVID-19 outbreak. Possible methodological biases of telephone surveys in older adults living in non-developed countries are also discussed. METHODS: Between June and September 2020, a random subsample of 720 people who had participated in the face-to-face V National Survey on Quality of Life in Older Adults in Chile conducted at the end of 2019 was followed up by telephone. Descriptive bivariate analyses were performed using t-test and non-parametric tests for independent variables, comparing the baseline sample with the current 2020 follow-up sample during the peak of the pandemic outbreak in Latin America. Furthermore, descriptive bivariate analysis through t-test and non-parametric test for paired samples compared the follow-up subsample at baseline with the not-included sample, examining possible biases of the telephone interview compared with the face-to-face interview. RESULTS: In the panel, there was no variation in self-rated health. The health symptoms that worsened were memory, stomach, and mood problems. Depressive symptoms and anxiety increased; similarly, smartphone users, social contacts, intergenerational co-residence and resilience increased. The telephone follow-up sample had a higher educational level and greater smartphone use than those not included in the subsample. CONCLUSIONS: Although some physical and mental health indicators have worsened during the pandemic, older adults mobilized resources that could allow them to maintain their quality of life, such as improved resilience. Thus, these findings can guide future research and the development of efficient strategies to improve these resources among older adults to ensure wellbeing.

Does the selective attrition of a panel survey of older people affect the multivariate estimations of subjective well-being?

PURPOSE: The increased population aging has resulted in a growing need for longitudinal studies about the quality of life among older people. Nevertheless, the results of these investigations could be biased because more disadvantaged people leave the original sample. The purpose of this study is to examine how the selective attrition observed in a panel survey affect multivariate models of subjective well-being (SWB). The question is if we could do reliable longitudinal investigations concerning the predictors of SWB in old age. METHODS: This paper examines attrition in a panel of older people in Chile. Attrition was evaluated in the variables that affect elderly SWB. Probit models were fitted to compare dropouts with nondropouts. Then, multivariate probit models were estimated on satisfaction and depressive symptoms, comparing dropouts and nondropouts. Finally, we compared weighted and unweighted multivariate probit models on SWB. RESULTS: The attrition rate in 2 years was 38.8%, including deaths and 32.9%, excluding them. Survey dropouts had lower satisfaction but not higher depressive symptoms. Among SWB predictors, people without a partner and with lower self-efficacy abandoned more the study. When applying the Becketti, Gould, Lillard, and Welch test, the probit coefficients of the predictor variables on SWB outcome variables were similar for dropouts and nondropouts. Finally, the comparison of multivariate models on SWB with weighting methods did not find substantial differences in the explanatory coefficients. CONCLUSION: Although some predictors of attrition were associated with SWB, attrition did not produce biased estimates in multivariate models of life satisfaction life or depressive symptoms in old age.

Gap junctions at the dendritic cell-T cell interface are key elements for antigen-dependent T cell activation.

The acquired immune response begins with Ag presentation by dendritic cells (DCs) to naive T cells in a heterocellular cell-cell contact-dependent process. Although both DCs and T cells are known to express connexin43, a gap junction protein subunit, the role of connexin43 on the initiation of T cell responses remains to be elucidated. In the present work, we report the formation of gap junctions between DCs and T cells and their role on T cell activation during Ag presentation by DCs. In cocultures of DCs and T cells, Lucifer yellow microinjected into DCs is transferred to adjacent transgenic CD4(+) T cells, only if the specific antigenic peptide was present at least during the first 24 h of cocultures. This dye transfer was sensitive to gap junction blockers, such as oleamide, and small peptides containing the extracellular loop sequences of conexin. Furthermore, in this system, gap junction blockers drastically reduced T cell activation as reflected by lower proliferation, CD69 expression, and IL-2 secretion. This lower T cell activation produced by gap junction blockers was not due to a lower expression of CD80, CD86, CD40, and MHC-II on DCs. Furthermore, gap junction blocker did not affect polyclonal activation of T cell induced with anti-CD3 plus anti-CD28 Abs in the absence of DCs. These results strongly suggest that functional gap junctions assemble at the interface between DCs and T cells during Ag presentation and that they play an essential role in T cell activation.

Imprinting of CCR9 on CD4 T cells requires IL-4 signaling on mesenteric lymph node dendritic cells.

It has recently been shown that IL-4 can educate dendritic cells (DC) to differentially affect T cell effector activity. In this study, we show that IL-4 can also act upon DC to instruct naive T cells to express the gut-associated homing receptor CCR9. Thus, effector T cells generated after coculture with mesenteric lymph node (MLN)-DC show a higher expression of CCR9 when activated in the presence of IL-4. In contrast, IL-4 had no effect on CCR9 expression when naive T cells were polyclonally activated in the absence of MLN-DC, suggesting that the effect of IL-4 on CCR9 expression passed through DC. Indeed, T cells activated by MLN-DC from IL-4Ralpha(-/-) mice showed a much lower CCR9 expression and a greatly reduced migration to the small intestine than T cells activated by wild-type MLN-DC even in the presence of IL-4. Consistent with the finding that the vitamin A metabolite retinoic acid (RA) induces gut-homing molecules on T cells, we further demonstrate that IL-4 up-regulated retinaldehyde dehydrogenase 2 mRNA on MLN-DC, a critical enzyme involved in the synthesis of RA. Moreover, LE135, a RA receptor antagonist, blocked the increased expression of CCR9 driven by IL-4-treated MLN-DC. Thus, besides the direct effect of RA on T cell gut tropism, our results show that the induction of a gut-homing phenotype on CD4(+) T cells is also influenced by the effect of IL-4 on gut-associated DC.

The essential role of chemokines in the selective regulation of lymphocyte homing.

Knowledge of lymphocyte migration has become a major issue in our understanding of acquired immunity. The selective migration of naïve, effector, memory and regulatory T-cells is a multiple step process regulated by a specific arrangement of cytokines, chemokines and adhesion receptors that guide these cells to specific locations. Recent research has outlined two major pathways of lymphocyte trafficking under homeostatic and inflammatory conditions, one concerning tropism to cutaneous tissue and a second one related to mucosal-associated sites. In this article we will outline our present understanding of the role of cytokines and chemokines as regulators of lymphocyte migration through tissues.