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1.
J Biol Chem ; 300(9): 107630, 2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39098526

ABSTRACT

CD22 (also known as Siglec-2) is an inhibitory receptor expressed in B cells. CD22 specifically recognizes α2,6 sialic acid and interacts with α2,6 sialylated membrane proteins expressed on the same cell (cis-ligands) and those derived from outside of the cell (trans-ligands). Previously, CD22 cis-ligands were shown to regulate the activity of CD22, thereby regulating both BCR ligation-induced signaling and low-level "tonic" signaling in the absence of BCR ligation that regulates the survival and differentiation of B cells. Mouse CD22 prefers Neu5Gc to Neu5Ac thereby binding to α2,6-linked Neu5Gc with high affinity. Although human CD22 binds to a distinct α2,6 sialylated glycan with high affinity, expression of high-affinity ligands is regulated in a conserved and stringent manner. However, how high- versus low-affinity CD22 ligands regulate B cells is poorly understood. Here we demonstrate that the interaction of CD22 with the endogenous ligands enhances BCR ligation-induced signaling but reduces tonic signaling in Cmah-/- mouse B cells deficient in Neu5Gc as well as wild-type B cells. Moreover, Cmah-/- B cells do not show alterations in the phenotypes correlated to tonic signaling. These results indicate that low-affinity interaction of the CD22 cis-ligands with CD22 is sufficient for the regulation of B cell signaling, and suggest that expression of high-affinity CD22 ligands might be involved in the regulation of B cells by competing for the binding of CD22 with exogenous trans-ligands of CD22.

2.
Biochem Biophys Rep ; 39: 101746, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38910870

ABSTRACT

Dermal fibroblasts play a crucial role in skin structure and function by producing hyaluronic acid. Piceatannol (PIC), a polyphenol abundant in passion fruit seeds, has been reported to activate sirtuin 1 (SIRT1). Clinical trials have demonstrated that PIC intake improves skin moisture and maintains skin elasticity, yet the underlying mechanism remains unclear. This study aimed to investigate the effects of PIC on hyaluronic acid biosynthesis and the involvement of SIRT1 in this process. Human dermal fibroblast Hs68 cells were stimulated with PIC, and the expression levels of HAS2 and HYAL2, key enzymes in hyaluronic acid biosynthesis, as well as SIRT1 expression, were assessed using quantitative real-time PCR. Additionally, the role of SIRT1 in the hyaluronic acid biosynthesis pathway during PIC stimulation was examined using a SIRT1 inhibitor. The results demonstrated that PIC increased HAS2 expression while decreasing HYAL2 expression in human dermal fibroblasts. Furthermore, PIC enhanced SIRT1 expression, and pre-treatment with a SIRT1 inhibitor mitigated PIC-induced upregulation of HAS2, suggesting that PIC promotes hyaluronic acid synthesis by inducing SIRT1. These findings suggest that PIC could serve as a beneficial food ingredient, enhancing skin structure and function by promoting hyaluronic acid biosynthesis via SIRT1 induction.

3.
Life (Basel) ; 14(5)2024 May 05.
Article in English | MEDLINE | ID: mdl-38792610

ABSTRACT

Piceatannol (PIC), a polyphenol abundant in passion fruit seeds, is reported to promote fat metabolism. This study investigated whether PIC affects sirtuin 1 (SIRT1) expression and metabolic factors in C2C12 skeletal muscle cells. C2C12 myotubes were stimulated with PIC, and alterations in gene expression, protein levels, mitochondrial DNA content, and fatty acid levels were assessed using real-time PCR, Western blotting, and Nile red staining. Furthermore, we examined changes in SIRT1 expression following the consumption of a test food containing 100 mg PIC for 2 weeks among adults with varying age and body mass index ranges. Both PIC and passion fruit seed extract induced SIRT1 expression in C2C12 myotubes to a greater extent than resveratrol. PIC also increased the expression of genes associated with mitochondrial biogenesis and fatty acid utilization, increased mitochondrial DNA content, and suppressed oleic acid-induced fat accumulation. Moreover, participants who consumed PIC exhibited significantly higher SIRT1 mRNA expression in whole blood compared to those in the placebo group. These findings suggest that PIC induces SIRT1 expression both in vitro and in the human body, which may promote mitochondrial biosynthesis and fat metabolism.

5.
J Cardiol Cases ; 29(2): 89-92, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38362579

ABSTRACT

Insertable cardiac monitors (ICMs) are small electrocardiographs implanted subcutaneously to automatically record electrocardiograms when arrhythmia is detected in patients with syncope. If the ICM misses a significant arrhythmia, it may delay the diagnosis of arrhythmogenic syncope and put the patient at risk. Herein, we describe a case of undetected cardiac arrest in a patient with ICM. An 87-year-old man with syncope was admitted to the hospital. After 8 days of monitoring, the cause could not be determined, and an ICM was implanted. Nine hours after implantation, the patient experienced cardiopulmonary arrest. Despite a body surface electrocardiogram showing ventricular flatline and fibrillation, the ICM failed to record. The cause of failure to record was considered to be the fluctuation in the R-wave amplitude of the ICM and noise oversensing. In conclusion, albeit infrequently, ICMs might overlook life-threatening arrhythmias. Even in cases where the ICM fails to detect an arrhythmia matching the symptoms, it may not be feasible to entirely rule out the presence of arrhythmias. Learning objective: Insertable cardiac monitors (ICMs) are used to diagnose arrhythmogenic syncope. However, extremely infrequently, ICM may fail to record life-threatening arrhythmias. Failure to capture arrhythmias can happen due to an unfortunate combination of factors such as a low amplitude of the recorded R wave and noise. Even in cases where the ICM does not detect an arrhythmia that matches the symptoms, it may not be feasible to completely exclude the presence of arrhythmias.

6.
Am J Emerg Med ; 78: 206-214, 2024 04.
Article in English | MEDLINE | ID: mdl-38330835

ABSTRACT

BACKGROUND: Ultrasound-guided central venous catheterization (CVC) has become the standard of care. However, providers use a variety of approaches, encompassing the internal jugular vein (IJV), supraclavicular subclavian vein (SupraSCV), infraclavicular subclavian vein (InfraSCV), proximal axillary vein (ProxiAV), distal axillary vein (DistalAV), and femoral vein. OBJECTIVE: This review aimed to compare the first-pass success rate and arterial puncture rate for different approaches to ultrasound-guided CVC above the diaphragm. METHODS: In May 2023, Embase, MEDLINE, CENTRAL, ClinicalTrials.gov, and World Health Organization International Clinical Trials Platform were searched for randomized controlled trials (RCTs) comparing the 5 CVC approaches. The Confidence in Network Meta-Analysis tool was used to assess confidence. Thirteen RCTs (4418 participants and 13 comparisons) were included in this review. RESULTS: The SupraSCV approach likely increased the proportion of first-attempt successes compared to the other 4 approaches. The SupraSCV first-attempt success demonstrated risk ratios (RRs) > 1.21 with a lower 95% confidence interval (CI) exceeding 1. Compared to the IJV, the SupraSCV approach likely increased the first-attempt success proportion (RR 1.22; 95% confidence interval [CI] 1.06-1.40, moderate confidence), whereas the DistalAV approach reduced it (RR 0.72; 95% CI 0.59-0.87, high confidence). Artery puncture had little to no difference across all approaches (low to high confidence). CONCLUSION: Considering first-attempt success and mechanical complications, the SupraSCV may emerge as the preferred approach, while DistalAV might be the least preferable approach. Nevertheless, head-to-head studies comparing the approaches with the greatest first attempt success should be undertaken.


Subject(s)
Catheterization, Central Venous , Jugular Veins , Network Meta-Analysis , Subclavian Vein , Ultrasonography, Interventional , Humans , Catheterization, Central Venous/methods , Ultrasonography, Interventional/methods , Subclavian Vein/diagnostic imaging , Jugular Veins/diagnostic imaging , Neck/blood supply , Neck/diagnostic imaging , Femoral Vein/diagnostic imaging , Axillary Vein/diagnostic imaging , Randomized Controlled Trials as Topic
7.
Diabetol Int ; 15(1): 41-57, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38264219

ABSTRACT

Aim: In order to achieve good glycemic control, the prevention and management of insulin balls is important for diabetic patients during insulin therapy. However, insulin balls still occur within the clinical setting. This review evaluated the effectiveness of programs designed to manage insulin balls. Methods: A scoping review was conducted based on the Japanese and English literature available from a systematic literature search conducted from January 1964 to March 2022. Three databases were searched: PubMed, CINAHL, and Ichushi-Web. Results: A total of 33 articles met the inclusion criteria, which consisted of 3 for prevention management of insulin balls and 30 for management after the occurrence of insulin balls. Findings for prevention management suggested that the insulin injection technique education (avoidance of repeated injections to the same site) and providing knowledge (about insulin balls) prevented the appearance of insulin balls. As for post-occurrence management, insulin injection technique education (avoidance of injections to the insulin ball, avoidance of repeated injections to the same site, and switching the injection site) improved blood glucose control. Hypoglycemia was observed in all studies that included an assessment of hypoglycemia. None of the studies evaluated long-term effects of either preventive or post-occurrence management. Conclusions: Providing insulin injection technique education is an effective management protocol for insulin balls. Moreover, education about hypoglycemia is important for patients with insulin balls. Further studies to investigate the long-term effects in the management of insulin balls are needed.

9.
Nihon Yakurigaku Zasshi ; 158(2): 178-181, 2023.
Article in Japanese | MEDLINE | ID: mdl-36858502

ABSTRACT

Japanese Academy of Nursing Science (JANS) and the Japanese Pharmacological Society (JPS) have been conducting human interaction at each other's scientific meeting symposia in a home-and-away fashion since 2018. JANS and JPS have been working on a joint scientific project, "Scoping Review: Insulin Balls" since 2021. At the 95th Annual Meeting of the JPS held in 2022, we reported from a nursing perspective on the theme of "Assessment and preventive care of insulin balls from a scoping review". Subcutaneous injection into insulin balls has been reported to cause poor blood glucose control. Therefore, it is important to prevent insulin balls. In this study, we had the research questions, "What methods are available for assessment of the insulin injection site?" and "What is the care to prevent induration and how effective is it?" and conducted a scoping review. Regarding methods of injection site assessment, most of the literature identified the injection site by palpation, visual examination, and ultrasonography. About the preventive care, there were some reports of insulin balls occurring because patients have been injecting insulin at the same site, even though healthcare professionals instructed them to avoid the same site. Some of the literature had specific teaching methods such as hand site rotation and calendar injection method, and they were reported effective. In the future, we plan to proceed with the review including care after the development of insulin balls.


Subject(s)
Insulin , Humans , Insulin/administration & dosage , Insulin/adverse effects , Japan , Injections/adverse effects
10.
Sci Prog ; 106(1): 368504231158452, 2023.
Article in English | MEDLINE | ID: mdl-36862583

ABSTRACT

INTRODUCTION: The accumulation of fatigue and stress creates problems, including reductions in quality of life and productivity. OBJECTIVES: To investigate the effects of a far-infrared heater that heats the feet with ceramic balls on autonomic nervous activity and mood states. METHODS: This study was performed as a crossover trial. Participants comprised 20 women. On different days, each participant underwent 15 min of foot warming with the far-infrared heater (far-infrared group) or remained seated for 15 min (control group). Autonomic nervous activity (low-frequency component/high-frequency component, high-frequency) and mood states scales (Profile of Mood States Second Edition and Two-Dimensional Mood Scale for Self-monitoring and Self-regulation of Momentary Mood States) during the study intervention were measured and compared between groups. RESULTS: Low-frequency/high-frequency was significantly higher in the control group 10 min after the start of intervention than at baseline (P = .033). Low-frequency/high-frequency was significantly lower in the far-infrared group than in the control group at 5 min (P = .027), 10 min (P = .011), and 15 min (P = .015). High-frequency was significantly higher in the far-infrared group at 5 min (P = .008), 10 min (P = .004), and 15 min (P = .015) than at baseline. High-frequency 5 min after the start of intervention was significantly higher in the far-infrared group than in the control group (P = .033). POMS2 scores improved significantly more in the far-infrared group than in the control group, including in fatigue-inertia (P = .019), tension-anxiety (P = .025), and total mood disturbance (P = .019). Finally, the far-infrared group showed greater improvements in Two-Dimensional Mood Scale-Short Term scores such as stability (P = .002) and pleasure (P = .013). CONCLUSION: Using the far-infrared heater to heat the feet with ceramic balls stabilized and improved mood, reduced Fatigue-Inertia and Tension-Anxiety, and alleviated total mood disturbance. Parasympathetic nervous system activation was observed from 5 min after the start of heating, suggesting that short-duration heat stimulation of the feet is effective.


Subject(s)
Hot Temperature , Quality of Life , Humans , Female , Cross-Over Studies , Ceramics , Fatigue
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