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Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.
相似文献The exercise pressor reflex is a feedback mechanism engaged upon stimulation of mechano- and metabosensitive skeletal muscle afferents. Activation of these afferents elicits a reflex increase in heart rate, blood pressure, and ventilation in an intensity-dependent manner. Consequently, the exercise pressor reflex has been postulated to be one of the principal mediators of the cardiorespiratory responses to exercise. In this updated review, we will discuss classical and recent advancements in our understating of the exercise pressor reflex function in both human and animal models. Particular attention will be paid to the afferent mechanisms and pathways involved during its activation, its effects on different target organs, its potential role in the abnormal cardiovascular response to exercise in diseased states, and the impact of age and biological sex on these responses. Finally, we will highlight some unanswered questions in the literature that may inspire future investigations in the field.
相似文献This paper describes the design of a theory-informed pragmatic intervention for adolescent perinatal depression in primary care in Nigeria.
MethodsWe conducted Focus Group Discussions (FGDs) among 17 adolescent mothers and 25 maternal health care providers with experience in the receipt and provision of care for perinatal depression. The Consolidated Framework for Implementation Research (CFIR) was used to systematically examine the barriers and facilitators affecting adolescent mothers' use of an existing intervention package for depression. The Theoretical Domain Framework (TDF) and the Capability, Opportunity, Motivation, Behaviour (COM-B) model were used to analyze the results of the data across the five CFIR domains.
ResultsFGD analysis revealed that care providers lacked knowledge on approaches to engage young mothers in treatment. Young mothers had poor treatment engagement, low social support, and little interest in parenting. A main characteristic of the newly designed intervention is the inclusion of age-appropriate psychoeducation supported with weekly mobile phone calls, to address treatment engagement and parenting behaviours of young mothers. Also in the outer setting, low social support from relatives was addressed with education, “as need arises” phone calls, and the involvement of "neighborhood mothers”. In the inner settings, care providers’ behaviour is addressed with training to increase their capacity to engage young mothers in treatment.
ConclusionA theory-based approach helped develop an age-appropriate intervention package targeting depression and parenting skills deficit among perinatal adolescents in primary maternal care and in which a pragmatic use of mobile phone was key.
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