RESUMEN
The present study aimed to investigate the effect of use of N-95 masks on aided speech identification scores (SIS) in older adults with hearing loss. A total of 35 older adults in the age range of 60 years to 79 years (mean age of 64.97 years) participated in the present study. All the participants were diagnosed with moderate to severe sensorineural hearing loss. A prospective pre-test post-test study design was used in the present study with purposive convenient sampling method. The study was carried out in two phases. Phase 1 included the hearing aid fitting and verification. Phase 2 included measuring the speech identification scores (SIS) with and without N- 95 mask. The results of the present study showed that aided SIS scores obtained in without mask condition was significantly better than with N-95 mask condition. Thus is can be concluded that wearing of mask has detrimental effect of SIS in older adults. Hence audiologists can use this as a condition to counsel during hearing aid fitting and also to counsel about the decreased clarity issues due to wearing of mask.
RESUMEN
An essential component of developing successful neural stem cell (NSC)-based therapies involves the establishment of methodologies to noninvasively monitor grafted NSCs within brain tissues in real time. In this context, ex vivo labeling with ultrasmall superparamagnetic iron oxide (USPIO) particles has been shown to enable efficient tracking of transplanted NSCs via magnetic resonance imaging (MRI). However, whether and how USPIO labeling affects the intrinsic biology of NSCs is not thoroughly understood, and remains an active area of investigation. Here, we perform a comprehensive examination of rat NSC survival and regenerative function upon labeling with the USPIO, Molday ION Rhodamine B (MIRB), which allows for dual magnetic resonance and optical imaging. After optimization of labeling efficiency, two specific doses of MIRB (20 and 50 µg/mL) were chosen and were followed for the rest of the study. We observed that both MIRB doses supported the robust detection of NSCs, over an extended period of time in vitro and in vivo after transplantation into the striata of host rats, using MRI and post hoc fluorescence imaging. Both in culture and after neural transplantation, the higher 50 µg/mL MIRB dose significantly reduced the survival, proliferation, and differentiation rate of the NSCs. Interestingly, although the lower 20 µg/mL MIRB labeling did not produce overtly negative effects, it increased the proliferation and glial differentiation of the NSCs. Additionally, application of this dose also changed the morphological characteristics of neurons and glia produced after NSC differentiation. Importantly, the transplantation of NSCs labeled with either of the two MIRB doses upregulated the immune response in recipient animals. In particular, in animals receiving the 50 µg/mL MIRB-labeled NSCs, this immune response consisted of an increased number of CD68(+)-activated microglia, which appeared to have phagocytosed MIRB particles and cells contributing to an exaggerated MRI signal dropout in the animals. Overall, these results indicate that although USPIO particles, such as MIRB, may have advantageous labeling and magnetic resonance-sensitive features for NSC tracking, a further examination of their effects might be necessary before they can be used in clinical scenarios of cell-based transplantation.