Most of these college students should not be at great risk of hearing loss from their iPods when used conscientiously. Some concern is warranted for a small segment of these students who seemed to be most at risk because they listened to their iPods at high volume levels for long durations using earbuds, and reported that they may already have hearing loss due to their iPods.

Hearing and balance problems are prevalent among the elderly. Primary care physicians (PCPs) are important pivotal points of entry for ensuring that patients receive needed audiology services. New Medicare beneficiaries are entitled to one-time preventative examinations including hearing/balance screenings. A 35-item questionnaire was developed to assess physicians' participation in, knowledge about, and attitudes toward hearing/balance screenings and referrals for the elderly. The survey was mailed to 710 PCPs (19 undeliverable; 95 returned; response rate = 13.7%) in major metropolitan areas in the United States. Generally, these PCPs were not conducting hearing/balance screenings, aware of patient self-report screening questionnaires, or likely to screen in the future. They referred to audiologists and otolaryngologists mainly when patients complained of having hearing/balance difficulties, and they stated that these problems were important in the elderly and that the Medicare program was worthy of funding but that they had little time and were not reimbursed appropriately for screening. Therefore, PCPs could benefit from informational outreach campaigns on the prevalence of, negative HRQoL (health-related quality of life) effects from, and screening procedures for hearing/balance disorders in the elderly.

Toxoplasma gondii is an obligate intracellular parasite that can invade any nucleated cell of any warm-blooded animal. In a previous screen to identify virulence determinants, disruption of gene TgME49_305140 generated a T. gondii mutant that could not establish a chronic infection in mice. The protein product of TgME49_305140, here named TgPL3, is a 277 kDa protein with a patatin-like phospholipase (PLP) domain and a microtubule binding domain. Antibodies generated against TgPL3 show that it is localized to the apical cap. Using a rapid selection FACS-based CRISPR/Cas-9 method, a TgPL3 deletion strain (ΔTgPL3) was generated. ΔTgPL3 parasites have defects in host cell invasion, which may be caused by reduced rhoptry secretion. We generated complementation clones with either wild type TgPL3 or an active site mutation in the PLP domain by converting the catalytic serine to an alanine, ΔTgPL3::TgPL3 S1409A (S1409A). Complementation of ΔTgPL3 with wild type TgPL3 restored all phenotypes, while S1409A did not, suggesting that phospholipase activity is necessary for these phenotypes. ΔTgPL3 and S1409A parasites are also virtually avirulent in vivo but induce a robust antibody response. Vaccination with ΔTgPL3 and S1409A parasites protected mice against subsequent challenge with a lethal dose of Type I T. gondii parasites, making ΔTgPL3 a compelling vaccine candidate. These results demonstrate that TgPL3 has a role in rhoptry secretion, host cell invasion and survival of T. gondii during acute mouse infection.