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Keloid formation has been linked to aberrant fibroblast activity, exacerbated by growth factors and inflammatory mediators. Prostaglandin E2 (PGE2), synthesized from arachidonic acid by cyclooxygenases (COX) and synthases (PGES), acts as both an inflammatory mediator and fibroblast modulator. Although PGE2 has known antifibrotic effects in the lower airway, its role in dermal fibrosis in general, and keloid formation in particular, remains unclear. This study focused on: (1) the effects of PGE2 on keloid fibroblast migration, contraction, and collagen synthesis and (2) endogenous PGE2 synthesis in response interleukin-1beta. PGE2 decreased keloid fibroblast migration and contraction via an EP2/EP4-cAMP mechanism that disrupted actin cytoskeletal dynamics and reversed transforming growth factor-beta1-induced collagen I and III synthesis. Impaired fibroblast PGE2 production has been linked to lower airway fibrosis and recently to keloid formation. Here, we showed that interleukin-1beta stimulation leads to nuclear factor-kappaB translocation to the nucleus, resulting in up-regulation of COX-2 and microsomal PGE2 synthase 1. Up-regulation of COX-2 in, and secretion of PGE2 by keloid fibroblasts are diminished compared with their normal fibroblast counterparts. We suggest that the antifibrotic effects of PGE2 during keloid formation are potentially diminished due to aberrant paracrine fibroblast signaling. Exogenous PGE2 may supplement decreased endogenous levels and inhibit keloid formation or progression.

Age-related hearing loss (ARHL), known as presbycusis, is characterized by progressive deterioration of auditory sensitivity, loss of the auditory sensory cells, and central processing functions associated with the aging process. ARHL is the third most prevalent chronic condition in older Americans, after hypertension and arthritis, and is a leading cause of adult hearing handicaps in the United States. The prevalence of ARHL is expected to rise for the next several decades with the increasing aging Baby Boomer population. Nevertheless, ARHL remains an often undetected, underestimated and neglected condition in the geriatric population due to a slow development process of the disease. If left untreated, the impact of ARHL on patients, significant others, and the society as a whole would be significant. The purpose of this review is to raise the awareness of ARHL, to update our current understanding of ARHL with a focus on age-related deficits in auditory and cognitive processing of speech, and to explore strategies of prevention, identification, amplification, and aural rehabilitation. The ultimate goal is to improve the quality of hearing health care and the overall quality of life of the Baby Boomer generation.

Low socioeconomic status (SES) during childhood and adolescence has been found to predict greater susceptibility to common cold viruses in adults. Here, we test whether low childhood SES is associated with shorter leukocyte telomere length in adulthood, and whether telomere length mediates the association between childhood SES and susceptibility to acute upper respiratory disease in adulthood. At baseline, 196 healthy volunteers reported whether they currently owned their home and, for each year of their childhood, whether their parents owned the family home. Volunteers also had blood drawn for assessment of specific antibody to the challenge virus, and for CD8+CD28− T-lymphocyte telomere length (in a subset, n = 135). They were subsequently quarantined in a hotel, exposed to a virus (rhinovirus [RV] 39) that causes a common cold and followed for infection and illness (clinical cold) over 5 post-exposure days. Lower childhood SES as measured by fewer years of parental home ownership was associated with shorter adult CD8+CD28− telomere length and with an increased probability of developing infection and clinical illness when exposed to a common cold virus in adulthood. These associations were independent of adult SES, age, sex, race, body mass, neuroticism, and childhood family characteristics. Associations with infections and colds were also independent of pre-challenge viral-specific antibody and season. Further analyses do not support mediating roles for smoking, alcohol consumption or physical activity but suggest that CD8+CD28− cell telomere length may act as a partial mediator of the associations between childhood SES and infection and childhood SES and colds.

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