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The interindividual heterogeneity of the immune system likely determines the personal risk for acquiring infections and developing diseases with inflammatory components. In addition to genetic factors, the immune system's heterogeneity is driven by diverging exposures of leukocytes and their progenitors to infections, vaccinations, and health behavior, including lifestyle-related stimuli such as diet, physical inactivity, and psychosocial stress. We review how such experiences alter immune cell responses to concurrent and subsequent challenges, leading to either improved host resilience or disease susceptibility due to a muted or overzealous immune system, with a primary focus on the contribution of innate immune cells. We explore the involvement of diverse mechanisms, including trained immunity, and their relevance for infections and cardiovascular disease, as these prevalent conditions are heavily influenced by immune cell abundance and phenotypic adaptions. Understanding the mechanistic bases of immune modulations by prior or co-exposures may lead to new therapies targeting dysfunctional inflammation.

Cardiac macrophages represent a heterogeneous cell population with distinct origins, dynamics, and functions. Recent studies have revealed that C-C Chemokine Receptor 2 positive (CCR2(+)) macrophages derived from infiltrating monocytes regulate myocardial inflammation and heart failure pathogenesis. Comparatively little is known about the functions of tissue resident (CCR2(−)) macrophages. Herein, we identified an essential role for CCR2(−) macrophages in the chronically failing heart. Depletion of CCR2(−) macrophages in mice with dilated cardiomyopathy accelerated mortality and impaired ventricular remodeling and coronary angiogenesis, adaptive changes necessary to maintain cardiac output in the setting of reduced cardiac contractility. Mechanistically, CCR2(−) macrophages interacted with neighboring cardiomyocytes via focal adhesion complexes and were activated in response to mechanical stretch through a transient receptor potential vanilloid 4 (TRPV4) dependent pathway that controlled growth factor expression. These findings establish a role for tissue resident macrophages in adaptive cardiac remodeling and implicate mechanical sensing in cardiac macrophage activation.

Introduction Since a majority of Indians do not drive automobiles, one item on the Epworth Sleepiness Scale requires modification and validation. In addition, data collected by us, indicated that a vast majority of rural and urban Indians regularly spend time in prayer/spiritual activity. The main purpose of this study was to develop a cross-cultural adaptation of the Epworth Sleepiness Scale for a north-Indian population (ESS-I). The study also provides evidence of reliability and validity of the modified version. Materials and methods The subjects included were normal volunteers aged 18–75 years (group 1) (n = 100), compared with patients with complaints of excessive daytime sleepiness, who had undergone polysomnography (group 2) (n = 22) and patients who had undergone MSLT (group 3)(n = 10). The study was carried out in four phases: translation and retranslation of the original scale with modification of item8 (mainly addition of option of question on ‘while offering prayers or in spiritual activity’); reliability (test–retest) (n = 30); internal consistency (using Cronbach’s alpha index) (n = 102); and sensitivity to change (n = 8). Results Group 1 showed spiritual activity as significantly more common activity than driving. The Cronbach’s a for the modified version, was 0.892, and this was not improved by removing the modified item. The a value for group 1 versus group 2&3 was 0.667 and 0.892, respectively. The scale was reliable over time (test–retest) and it was sensitive to sleepiness change in patients with obstructive sleep apnea during treatment. Conclusion The ESS-I, is comparable to the original scale, It is reliable, valid, and change-sensitive. It is proposed that the modified version can be very useful for detecting sleepiness among Indian population, especially those who do not drive their own vehicles. Acknowledgements I am highly greatful to Jyoti Katoch, Shivani, Bharat Singh, Umesh Kumar, Nikhil at the Sleep disorders clinic and lab, Department of Neurology, AIIMS, New Delhi, India and my family specially my mother for their constant support.