The Ultra fit community mask-Toward maximal respiratory protection via personalized face fit.

Effective masking policies to prevent the spread of airborne infections depend on public access to masks with high filtration efficacy. However, poor face-fit is almost universally present in pleated multilayer disposable face masks, severely limiting both individual and community respiratory protection. We developed a set of simple mask modifications to mass-manufactured disposable masks, the most common type of mask used by the public, that dramatically improves both their personalized fit and performance in a low-cost and scalable manner. These modifications comprise a user-moldable full mask periphery wire, integrated earloop tension adjusters, and an inner flange to trap respiratory droplets. We demonstrate that these simple design changes improve quantitative fit factor by 320%, triples the level of protection against aerosolized droplets, and approaches the model efficacy of N95 respirators in preventing the community spread of COVID-19, for an estimated additional cost of less than 5 cents per mask with automated production.

Management of group B Streptococcus in pregnant women with penicillin allergy.

OBJECTIVE: To determine whether group B Streptococcus (GBS)-colonized pregnant women who report a history of penicillin allergy can safely undergo diagnostic evaluation to rule out or confirm the potential for an IgE-mediated (allergic) reaction to penicillin. STUDY DESIGN: Over 18 months, all pregnant women with GBS-positive vaginal/rectal cultures and a history of penicillin allergy were referred to the Department of Allergy and Immunology for a history and possible skin testing. Patients who had experienced anaphylaxis were advised to continue avoiding penicillin and were not skin tested. Women without such a history underwent immediate hypersensitivity (percutaneous and intradermal) testing using 2 penicillin reagents with controls. If skin testing was negative, intrapartum antimicrobial prophylaxis with intravenous penicillin was administered. RESULTS: Of 28 patients with both GBS colonization and "penicillin allergy," 25 (89%) had negative skin testing to penicillin and received intrapartum penicillin for GBS prophylaxis without adverse reactions. Skin testing was positive in 2 patients, and intrapartum penicillin was not administered. Penicillin skin testing was not performed on 1 patient due to a history of anaphylaxis from penicillin. CONCLUSION: These results indicate that most pregnant women reporting penicillin allergy undergo negative skin tests and are able to safely receive intrapartum penicillin GBS prophylaxis.

Yin Yang 1 is a lipopolysaccharide-inducible activator of the murine 3' Igh enhancer, hs3.

The 3' Igh enhancers, DNase I hypersensitive site (hs) 3B and/or hs4, are required for germline transcription, and hence, class switch recombination for multiple isotypes. A number of hs3-binding transcription factors have been identified by EMSA, including octamer and NF-kappa B family members, and Pax5. We have found that the binding of the transcription factor, Yin Yang 1 (YY1), to hs3 and to the mu E1 site of the intronic enhancer, E mu, is induced in primary splenic B cells after approximately 48 h in response to LPS and other activators of class switch recombination. Transient transfection experiments in B cell lines indicate that YY1 is an activator of hs3. Interestingly, levels of YY1 expression are unchanged in resting and LPS-stimulated B cells. Mixing experiments followed by EMSA showed that a protein present in resting B cells prevented binding of YY1 to DNA. We found that recombinant retinoblastoma protein (Rb) inhibited binding of YY1 to hs3 in a dose-dependent manner, and we have identified complexes of endogenous YY1 with the Rb in resting B cells, but not in LPS-stimulated B cells. A difference in Rb phosphorylation state was also confirmed between resting (G(0)) B cells and LPS-stimulated B cells. These observations suggest that the interaction of YY1 with hypophosphorylated Rb in resting B cells prevents interaction of YY1 with DNA. After stimulation with class-switching activators, such as LPS, Rb becomes hyperphosphorylated and YY1 is released and can then bind to the hs3 enhancer and E mu.