LRP1-deficient leptin receptor-positive cells in periodontal ligament tissue reduce alveolar bone mass by inhibiting bone formation.

OBJECTIVE: Leptin receptor-positive (LepR+) periodontal ligament (PDL) cells play a crucial role in osteogenesis during tooth socket healing and orthodontic tooth movement; however, the factors regulating osteoblast differentiation remain unclear. This study aimed to demonstrate the function of low-density lipoprotein receptor-related protein 1 (LRP1) in alveolar bone formation by examining conditional knockout (cKO) mice lacking LRP1 in LepR+ cells. DESIGN: Bone mass and formation were examined via bone morphometric analysis. Bone formation and resorption activities were determined via histochemical staining. Additionally, PDL cells collected from molars were induced to differentiate into osteoblasts with the addition of BMP2 and to mineralize with the addition of osteogenic medium. Osteoblast differentiation of PDL cells was examined by measuring the expression of osteoblast markers. RESULTS: Bone morphometry analysis revealed decreased mineral apposition rate and alveolar bone mass in cKO mice. Additionally, cKO mice showed a decreased number of osterix-positive cells in the PDL. cKO mice had a large number of osteoclasts around the alveolar bone near the root apex and mesial surface of the tooth. In the PDL cells from cKO mice, inhibition of mineralized matrix formation and decreased expression of alkaline phosphatase, osterix, bone sialoprotein, and osteocalcin were observed even when BMP2 was added to the medium. BMP2, BMP4, and osteoprotegerin expression also decreased, but RANKL expression increased dominantly. CONCLUSION: LRP1 in LepR+ cells promotes bone formation by stimulating osteoblast differentiation. Our findings can contribute to clinical research on bone diseases and help elucidate bone metabolism in the periodontal tissue.

Mitigation of paclitaxel-induced peripheral neuropathy in breast cancer patients using limb-cooling apparatus: a study protocol for a randomized controlled trial.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common adverse events that can significantly impair the quality of life of patients. Although limb cooling may be beneficial for preventing CIPN, logistical challenges exist in ensuring consistent efficacy and safety. The purpose of this randomized controlled trial is to validate whether limb cooling with strict temperature control can reduce CIPN in patients with breast cancer receiving weekly paclitaxel as a perioperative treatment. Methods: This study is a multicenter, double-blinded, randomized controlled trial. We plan to enroll patients with breast cancer who are scheduled to receive 12 weekly doses of paclitaxel (60 min 80 mg/m2 intravenous infusion) as perioperative chemotherapy. Patients will be randomly divided into the intervention or control groups and undergo limb cooling therapy maintained at a constant temperature of 13°C and 25°C, respectively. The primary endpoint is the proportion of patients who report Patient Neurotoxicity Questionnaire (PNQ) ≥ D in their limbs by the end of the study treatment or at the time of discontinuation. Discussion: The results of this trial will contribute to the establishment of new evidence for limb cooling therapy in the mitigation of CIPN and present a safe and stable cooling device that may be suitable for use in the clinic. Clinical trial registration: https://jrct.niph.go.jp/en-latest-detail/jRCT2032210115, identifier jRCT2032210115.

[Two cases of allergies due to Anisakis simplex, positive to specific IgE for Ani s 12 allergen].

We report 2 cases of immediate allergies to Anisakis after ingestion of seafood. In case 1, after ingestion of flatfish, sea bream and mackerel, wheals and dyspnea occurred. Result of ImmunoCAP was class 5 for Anisakis. ELISA for specific IgE showed that the patient serum strongly reacted to Ani s 12. In case 2, after ingestion of flatfish and yellowtail, pruritus and dyspnea occurred. Result of ImmunoCAP was class 6 for Anisakis. ELISA for specific IgE showed that the patient serum reacted to Ani s 1, 4, 6 and 12. In both cases, skin prick tests were negative for suspected seafoods. These data suggests the possibility Ani s 12 is a major allergen of Anisakis allergy besides Ani s 1, 2 and 7. Ani s 12 is an allergen that was first reported in 2011. The reactivity of Ani s 12 specific IgE with ELISA may become useful for the diagnosis of Anisakis allergy.