T helper type 1 (Th1) cells are responsible for cell-mediated immunity against invading pathogens, while Th2 cells provide help to B cells and control allergic responses. The polarization of naïve Th cells into Th1 or Th2 subsets is controlled by dendritic cells (DCs) migrating from the periphery to draining lymph nodes. Migrating DCs carry not only antigen-specific 'signal 1' and costimulatory 'signal 2', but also Th-polarizing 'signal 3' that reflects the nature of the pathogen and the character of the infected tissue. Any changes imposed by external factors on the DC lifecycle may result in an inappropriate immune response. Here we show that DCs developed in a nicotinic environment (nicDCs) fail to support the terminal development of effector memory Th1 cells due to their differential expression of costimulatory molecules and lack of IL-12 production. Interestingly, they adopt critical Th1-promoting function necessary to prevent and fight infections only when the total balance of environmental signals strongly favors Th1 immunity. Notably, in a Th2-biased environment, nicDCs provoke stronger than normal Th2 responses which predisposes the development and exacerbation of asthma. These results help explain the two opposing effects of cigarette smoke on respiratory immune defense mechanisms: (a) immunosuppression against infectious agents and (b) exacerbation of asthma.
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http://dx.doi.org/10.1016/j.imlet.2005.10.024 | DOI Listing |
Matern Child Health J
January 2025
Office of the Director, Office of Readiness and Response, CDC, Atlanta, GA, USA.
Objectives: This study aimed to estimate the prevalence of homelessness shortly before or during pregnancy and describe differences in maternal characteristics and adverse birth outcomes between people reporting homelessness and not reporting homelessness.
Methods: We used 2016-2020 Pregnancy Risk Assessment Monitoring System (PRAMS) data from 31 sites to estimate the prevalence of self-reported homelessness during the 12 months before giving birth. We used logistic regression models to evaluate the association between homelessness and adverse birth outcomes, specifically small for gestational age (SGA), low birth weight (LBW), and preterm birth (PTB).
Int Forum Allergy Rhinol
January 2025
Division of Division of Rhinology & Skull Base Surgery Department of Otolaryngology, University of Florida, Gainesville, Florida, USA.
Rationale: Smoking has been shown to be associated with circulating deficiencies in 25(OH)D3 and reduced sinonasal tissue levels of the active form of vitamin D, 1,25(OH)2D3. Given vitamin D's ability to reduce inflammation, we sought to examine if intranasal (IN) delivery of calcitriol [clinical analog of 1,25(OH)2D3] could reduce inflammation and improve disease severity in a murine model of chronic cigarette smoke-induced sinonasal inflammation (CS-SI).
Methods: Mice were exposed to CS 5 h/day, 5 days/week for 9 months, and then began IN calcitriol three times per week for 4 weeks.
Lancet Reg Health Southeast Asia
January 2025
British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK.
Background: South Asians may be particularly susceptible to premature myocardial infarction (MI) owing both to conventional cardiovascular risk factors and practices distinctive to South Asia. Identifying modifiable risk factors for MI in these populations could inform prevention strategies. We have, therefore, studied conventional risk factors and other characteristics in relation to occurrence of first MI in Bangladesh.
View Article and Find Full Text PDFHeliyon
January 2025
School of Public Health, University of Alberta, 11405 87 Ave NW, Edmonton, Alberta, T6G 1C9, Canada.
Background: Based on the socio-ecological model of health, socioeconomic policy is an important determinant of population health. Spending decisions by public health units (PHU) have been shown to be associated with population health outcomes. Some studies have found greater PHU spending to be associated with improved population health, while others report mixed findings, warranting further research.
View Article and Find Full Text PDFCureus
December 2024
Department of Surgery, Arabian Gulf University, Manama, BHR.
Periductal mastitis (PM) is a form of nonlactational mastitis. The clinical picture varies from mild periareolar inflammation to frank retroareolar abscess formation. A huge amount of literature is incriminating cigarette smoking as a major contributing factor to the etiology of PM, and cessation of smoking is essential for a successful treatment.
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