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Background/Objectives: Undernutrition increases the mortality risk in older persons requiring long-term care; further, it is associated with oral functions such as swallowing and chewing. Moreover, occlusion affects oral function and is crucially involved in nutritional intake. The present study aimed to examine the association between the number of molar occlusions and undernutrition according to body mass index (BMI) in older persons requiring long-term care. Methods: Japanese older persons requiring long-term care were categorized based on BMI (<20 kg/m2 vs. 20 kg/m2). We examined the association between undernutrition and the number of molar occlusions (one in each of the left and right premolars and molars, for a total of four). Results: Among 893 included participants, 440 (49.3%) had BMI < 20 kg/m2 and 453 (50.7%) had BMI > 20 kg/m2. Binomial logistic regression analysis revealed that BMI < 20 kg/m2 was significantly associated with increased number of molar occlusions (odds ratio: 0.52–0.70, 95% CI: 0.28–1.00). This indicated that a decrease in the number of molar occlusions was associated with malnutrition as determined through BMI in older persons requiring long-term care and residing in long-term care insurance facilities in Japan. Conclusions: Our findings suggest that maintaining occlusal support may help maintain nutritional status in older persons requiring long-term care. [ABSTRACT FROM AUTHOR]

While silk fibroin (SF) obtained from silkworm cocoons is expected to become a next-generation natural polymer, a fabrication method for SF-based artificial nerve conduits (SFCs) has not yet been established. Here, we report a bioresorbable SFC, fabricated using a novel freeze–thaw process, which ensures biosafety by avoiding any harmful chemical additives. The SFC demonstrated favorable biocompatibility (high hydrophilicity and porosity with a water content of > 90%), structural stability (stiffness, toughness, and elasticity), and biodegradability, making it an ideal candidate for nerve regeneration. We evaluated the nerve-regenerative effects of the SFC in a rat sciatic-nerve-defect model, including its motor and sensory function recovery as well as histological regeneration. We found that SFC transplantation significantly promoted functional recovery and nerve regeneration compared to silicone tubes and was almost equally effective as autologous nerve transplantation. Histological analyses indicated that vascularization and M2 macrophage recruitment were pronounced inside the SFC. These results suggest that the unique properties of the SFC further enhanced the peripheral nerve regeneration mechanism. As no SFC has been applied in clinical practice, the SFC reported herein may be a promising candidate for repairing extensive peripheral nerve defects. [ABSTRACT FROM AUTHOR]

Regeneration of articular cartilage remains a challenge for patients who have undergone cartilage injury, osteochondritis dissecans and osteoarthritis. Here, we describe a new recombinant silk fibroin with basic fibroblast growth factor (bFGF) binding peptide, which has a genetically introduced sequence PLLQATLGGGS, named P7. In this study, we cultured a human mesenchymal cell line derived from bone marrow, UE6E7-16, in wild-type fibroin sponge (FS) and recombinant silk fibroin sponge with P7 peptide (P7 FS). We compared cell proliferation, chondrogenic differentiation and cartilaginous tissue formation between the two types of sponge. After stimulation with bFGF at 3 ng/mL, P7 FS showed significantly higher cell growth (1.2-fold) and higher cellular DNA content (5.6-fold) than did wild-type FS. To promote chondrogenic differentiation, cells were cultured in the presence of TGF-β at 10 ng/mL for 28 days. Immunostaining of P7 FS showed SOX9-positive cells comparable to wild-type FS. Alcian-Blue staining of P7 FS also showed cartilaginous tissue formation equivalent to wild-type FS. A significant increase in cell proliferation in P7 FS implies future clinical application of this transgenic fibroin for regeneration of articular cartilage. To produce cartilaginous tissue efficiently, transgenic fibroin sponges and culture conditions must be improved. Such changes should include the selection of growth factors involved in chondrogenic differentiation and cartilage formation. [ABSTRACT FROM AUTHOR]