Effects of face masks and acoustical environments on speech recognition by preschool children in an auralised classroom.

The potential impact of mask-wearing specifically on early-childhood speech and language development in classrooms has not been widely reported yet, although face masks are compulsory even in educational settings during the COVID-19 pandemic. This study investigated the combined effects of face-mask usage (no mask, surgical and KF94 masks) and room acoustics (RT 0.6 s and 1.2 s, SNR 12 dB and 22 dB) on speech recognition (KS-MWL-P) in preschool children (N = 67) in realistic classroom-acoustic settings using the auralisation technique. The face mask and reverberation time affected pre-schoolers' speech recognition scores. Reducing RT in the classroom improved the pre-schoolers' speech recognition that was reduced by face masks. Children aged 4 and 5 years were affected by face masks and RT more significantly than children aged 6 years. Appropriate room acoustics for classrooms and clear speech of teachers are recommended for better speech recognition in preschool, where pre-schoolers' language and speech development usually occur.

Mask-Wearing Behaviors after Two Years of Wearing Masks Due to COVID-19 in Korea: A Cross-Sectional Study.

In Korea, wearing masks in public places has become the norm during the prolonged coronavirus disease 2019 (COVID-19) pandemic. This cross-sectional study investigated the mask-wearing behavior of Koreans (n = 433) via online mode living in Seoul and Gwangju after wearing a mask in public spaces for two years due to COVID-19. The respondents selected their face masks based on season, gender, age, occupation, mask-wearing hours, mask filter performance, mask shape, and mask color. The general discomfort caused by wearing a mask was divided into physical and speech discomfort, and it was not correlated with anxiety when not wearing a face mask. Speech discomfort caused by wearing a mask was correlated with general discomfort, clear speech, vocal pain, anxiety, and only-indoor mask-off plans. Anxiety when not wearing a mask appeared to affect both indoor and outdoor mask-off plans. The more uncomfortable and less anxious respondents were when not wearing a mask, the sooner they wanted to discontinue wearing masks indoors and outdoors. It is expected that the use of masks will continue in the future and that there may be differences in the place and time of use of masks in Korea and around the world due to new infectious diseases and fine dust. Facial masks can be worn more comfortably and conveniently if the discomfort and anxiety of wearing a mask are improved by considering various behaviors when wearing a mask in the future.

Mask-Wearing Perception of Preschool Children in Korea during the COVID-19 Pandemic: A Cross-Sectional Study.

As the COVID-19 pandemic continues, wearing a mask has become a daily routine in Korea over the last two years. This study aims to investigate the mask-wearing perception of preschoolers (ages 4-6). The questionnaire comprised 17 yes-no closed-ended questions and two open-ended questions, and interviews of the children were conducted from January to February 2022, 15 months after mandatory mask wearing. Results showed that children were aware of the need to wear a mask to protect themselves and others from the coronavirus, and they perceived it as necessary and a good thing. Most children responded that they did not feel uncomfortable wearing a mask at preschool. This perception was thought to be influenced by the caregivers' perceptions of the mask in Korea. The way in which 4-5-year-olds perceived the mask differed from the way 6-year-olds did. Children aged between four and five seemed to perceive the mask as a physical self, while children aged six did not. As children who have experienced COVID-19 are growing up, attention is being focused on how the experience of wearing a mask affects their early childhood development.

Cleavage-Responsive Biofactory T Cells Suppress Infectious Diseases-Associated Hypercytokinemia.

Severe infectious diseases, such as coronavirus disease 2019 (COVID-19), can induce hypercytokinemia and multiple organ failure. In spite of the growing demand for peptide therapeutics against infectious diseases, current small molecule-based strategies still require frequent administration due to limited half-life and enzymatic digestion in blood. To overcome this challenge, a strategy to continuously express multi-level therapeutic peptide drugs on the surface of immune cells, is established. Here, chimeric T cells stably expressing therapeutic peptides are presented for treatment of severe infectious diseases. Using lentiviral system, T cells are engineered to express multi-level therapeutic peptides with matrix metallopeptidases- (MMP-) and tumor necrosis factor alpha converting enzyme- (TACE-) responsive cleavage sites on the surface. The enzymatic cleavage releases γ-carboxyglutamic acid of protein C (PC-Gla) domain and thrombin receptor agonist peptide (TRAP), which activate endothelial protein C receptor (EPCR) and protease-activated receptor-1 (PAR-1), respectively. These chimeric T cells prevent vascular damage in tissue-engineered blood vessel and suppress hypercytokinemia and lung tissue damages in vivo, demonstrating promise for use of engineered T cells against sepsis and other infectious-related diseases.

Nanocomplex-Mediated In Vivo Programming to Chimeric Antigen Receptor-M1 Macrophages for Cancer Therapy.

Chimeric antigen receptor-T (CAR-T) cell immunotherapy has shown impressive clinical outcomes for hematologic malignancies. However, its broader applications are challenged due to its complex ex vivo cell-manufacturing procedures and low therapeutic efficacy against solid tumors. The limited therapeutic effects are partially due to limited CAR-T cell infiltration to solid tumors and inactivation of CAR-T cells by the immunosuppressive tumor microenvironment. Here, a facile approach is presented to in vivo program macrophages, which can intrinsically penetrate solid tumors, into CAR-M1 macrophages displaying enhanced cancer-directed phagocytosis and anti-tumor activity. In vivo injected nanocomplexes of macrophage-targeting nanocarriers and CAR-interferon-γ-encoding plasmid DNA induce CAR-M1 macrophages that are capable of CAR-mediated cancer phagocytosis, anti-tumor immunomodulation, and inhibition of solid tumor growth. Together, this study describes an off-the-shelf CAR-macrophage therapy that is effective for solid tumors and avoids the complex and costly processes of ex vivo CAR-cell manufacturing.