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Objectives: Oral biofilms, including pathogens such as Porphyromonas gingivalis, are involved in the initiation and progression of various periodontal diseases. However, the treatment of these diseases is hindered by the limited efficacy of many antimicrobial materials in removing biofilms under the harsh conditions of the oral cavity. Our objective is to develop a gel-type antimicrobial agent with optimal physicochemical properties, strong tissue adhesion, prolonged antimicrobial activity, and biocompatibility to serve as an adjunctive treatment for periodontal diseases., Methods: Phenylboronic acid-conjugated alginate (Alg-PBA) was synthesized using a carbodiimide coupling agent. Alg-PBA was then combined with tannic acid (TA) to create an Alg-PBA/TA hydrogel. The composition of the hydrogel was optimized to enhance its mechanical strength and tissue adhesiveness. Additionally, the hydrogel's self-healing ability, erosion and release profile, biocompatibility, and antimicrobial activity against P. gingivalis were thoroughly characterized., Results: The Alg-PBA/TA hydrogels, with a final concentration of 5 wt% TA, exhibited both mechanical properties comparable to conventional Minocycline gel and strong tissue adhesiveness. In contrast, the Minocycline gel demonstrated negligible tissue adhesion. The Alg-PBA/TA hydrogel also retained its rheological properties under repeated 5 kPa stress owing to its self-healing capability, whereas the Minocycline gel showed irreversible changes in rheology after just one stress cycle. Additionally, Alg-PBA/TA hydrogels displayed a sustained erosion and TA release profile with minimal impact on the surrounding pH. Additionally, the hydrogels exhibited potent antimicrobial activity against P. gingivalis, effectively eliminating its biofilm without compromising the viability of MG-63 cells., Significance: The Alg-PBA/TA hydrogel demonstrates an optimal combination of mechanical strength, self-healing ability, tissue adhesiveness, excellent biocompatibility, and sustained antimicrobial activity against P. gingivalis. These attributes make it superior to conventional Minocycline gel. Thus, the Alg-PBA/TA hydrogel is a promising antiseptic candidate for adjunctive treatment of various periodontal diseases., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Findings from previous studies on the association between exposure to fine particulate matter (PM 2.5 ) and the risk of infant mortality were inconsistent. Thus, two main objectives of our study were to examine the association between exposure to PM 2.5 and specified infant mortality and to identify critical trimesters., Methods: We retrospectively created a birth cohort of singleton full-term infants born in South Korea between 2010 and 2015 using national birth and infant mortality data. The specified causes of infant mortality were circulatory and respiratory diseases, perinatal conditions, congenital anomalies, and sudden infant death syndrome. We performed 1:10 propensity score matching for various exposure windows: each trimester, prenatal, and postnatal (up to age 1). Conditional logistic regression was applied to estimate odds ratios (ORs) and 95% confidence intervals (CIs), while accounting for gestational age, birth weight, maternal education level, season of birth, and regions (metropolitan areas/provinces). We also conducted sex-stratified analyses and used different matching ratios for sensitivity analyses., Results: A total of 2,501,836 births and 761 deaths (0.03%) were identified in the birth cohort. We found an increased risk of infant mortality per 10 µg/m 3 increase in PM 2.5 exposure during the prenatal period (OR: 1.29, 95% CI: 1.07-1.55). Exposure in the 1st and 2nd trimesters was linked to an elevated risk (OR: 1.19, 95% CI: 1.02-1.37; OR: 1.21, 95% CI: 1.04-1.40). However, no association was shown in the third trimester. PM 2.5 exposure in the 1st and 2nd trimesters was associated with elevated male infant mortality, but did not reach statistical significance in female infants. The use of different matching ratios did not significantly affect the results., Conclusion: The study findings suggest that exposure to PM 2.5 could affect infant mortality differently by the timing of exposure and sex, which suggests a relation to fetal development. However, further investigations are warranted., (Copyright © 2020. Published by Elsevier Ltd.)

We genetically introduced the Fc-binding peptide (FcBP) into the loop of a self-assembled protein cage, ferritin, constituting four-fold symmetry at the surface to use it as a modular delivery nanoplatform. FcBP-presenting ferritin (FcBP-ferritin) formed very stable non-covalent complexes with both human and rabbit IgGs through the simple molecular recognition between the Fc region of the antibodies and the Fc-binding peptide clusters inserted onto the surface of FcBP-ferritin. This approach realized orientation-controlled display of antibodies on the surfaces of the protein cages simply by mixing without any complicated chemical conjugation. Using trastuzumab, a human anti-HER2 antibody used to treat patients with breast cancer, and a rabbit antibody to folate receptor, along with fluorescently labeled FcBP-ferritin, we demonstrated the specific binding of these complexes to breast cancer cells and folate receptor over-expressing cells, respectively, by fluorescent cell imaging. FcBP-ferritin may be potentially used as modular nanoplatforms for active targeted delivery vehicles or molecular imaging probes with a series of antibodies on demand., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Soluble glucocorticoid-induced tumor necrosis factor receptor (sGITR) is a potent stimulator of osteoclastogenesis. The mechanism by which it induces osteoclastogenesis was studied by culturing bone-marrow-derived macrophages (BMM) with conditioned medium from mouse bone marrow stromal cells. GITR and GITR ligand (GITRL) were expressed on the surface of bone marrow stromal cells, and sGITR-induced osteoclastogenesis was inhibited by anti-GITRL Ab, indicating that stimulatory effect of osteoclastogenesis by sGITR involved signaling via GITRL. Bone marrow stromal cells up-regulated cyclooxygenase-2 (COX-2) and produced prostaglandin E(2) (PGE(2)) early in their response to sGITR, and the stimulation of osteoclastogenesis was markedly inhibited by NS398, a COX-2 inhibitor. Later, sGITR markedly reduced the steady-state level of osteoprotegerin (OPG) mRNA and increased receptor activator of nuclear factor-kappaB ligand (RANKL) mRNA. NS398 blocked the sGITR-induced reduction of OPG mRNA but did not significantly affect the sGITR-induced rise in RANKL mRNA. This suggests that down-regulation of OPG by PGE(2) is involved in sGITR-induced osteoclast (OC) formation in the presence of conditioned medium from mouse bone marrow stromal cells.

We found that treatment of osteoclast (OC) precursors with soluble glucocorticoid-induced tumor necrosis factor receptor (sGITR) promoted osteoclastogenesis in the presence of macrophage colony-stimulating factor (M-CSF) and receptor for activation of nuclear factor-kappaB ligand (RANKL). Low levels of GITR and its ligand were expressed on the surface of OC precursor cells after incubation with RANKL. Stimulation of osteoclastogenesis by sGITR was blocked by neutralization with anti-GITR ligand antibody (Ab), whereas endogenous GITR did not affect osteoclastogenesis, indicating that enhancement of osteoclastogenesis by sGITR involves signaling via GITR ligand. The addition of sGITR decreased the level of interferon (IFN)-beta, and blockade of endogenous IFN-beta did not affect osteoclastogenesis stimulated by sGITR. We conclude that sGITR enhances osteoclastogenesis by acting on OC precursor cells to lower the level of IFN-beta.