Metabolic Bone

SUMMARY: The resistance to thyroid hormone syndrome (RTHβ) occurs uncommonly and requires a high level of clinical suspicion and specific investigations to reach a precise diagnosis and to avoid unnecessary and potentially harmful therapies. We report a case of a young male patient referred to our unit for SARS-CoV-2 infection and atrial fibrillation with elevated thyroid hormones and non-suppressed thyroid-stimulating hormone (TSH), for which antithyroid therapy was prescribed...

Research on biomaterials typically starts with cytocompatibility evaluation, using the ISO 10993-5 standard as a reference that relies on extract tests to determine whether the material is safe (cell metabolic activity should exceed 70 %). However, the generalized approach within the standard may not accurately reflect the material's behavior in direct contact with cells, raising concerns about its effectiveness. Calcium phosphates (CaPs) are a group of materials that, despite being highly biocompatible and promoting bone formation, still exhibit inconsistencies in basic cytotoxicity evaluations...

Chronic bone loss is an under-recognized complication of malaria, the underlying mechanism of which remains incompletely understood. We have previously shown that persistent accumulation of Plasmodium products in the bone marrow leads to chronic inflammation in osteoblast (OB) and osteoclast (OC) precursors causing bone loss through MyD88, an adaptor molecule for diverse inflammatory signals. However, the specific contribution of MyD88 signaling in OB or OC precursors in malaria-induced bone loss remains elusive...

Type 2 diabetes (T2D) increases fracture incidence and fracture-related mortality rates (KK.Cg-Ay/J. The Jackson Laboratory; Available from: https://www.jax.org/strain/002468 ). While numerous mouse models for T2D exist, few effectively stimulate persistent hyperglycemia in both sexes, and even fewer are suitable for bone studies. Commonly used models like db/db and ob/ob have altered leptin pathways, confounding bone-related findings since leptin regulates bone properties (Fajardo et al. in Journal of Bone and Mineral Research 29(5): 1025-1040, 2014)...

Osteogenesis imperfecta (OI) increases fracture risk due to changes in bone quantity and quality caused by mutations in collagen and its processing proteins. Current therapeutics improve bone quantity, but do not treat the underlying quality deficiencies. Male and female G610C+/- mice, a murine model of OI, were treated with a combination of raloxifene and in vivo axial tibial compressive loading starting at 10 weeks of age and continuing for 6 weeks to improve bone quantity and quality. Bone geometry and mechanical properties were measured to determine whole bone and tissue-level material properties...

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OBJECTIVE: The aim of this study was to produce and characterize triple-layered cell sheet constructs with varying cell compositions combined or not with the fibrin membrane scaffold obtained by the technology of Plasma Rich in Growth Factors (mPRGF). MATERIALS AND METHODS: Human primary cultures of periodontal ligament stem cells (hPDLSCs) were isolated, and their stemness nature was evaluated. Three types of triple-layered composite constructs were generated, composed solely of hPDLSCs or combined with human umbilical vein endothelial cells (HUVECs), either as a sandwiched endothelial layer or as coculture sheets of both cell phenotypes...

Romosozumab treatment results in a transient early increase in bone formation and sustained decrease in bone resorption. Histomorphometric analyses revealed that the primary bone-forming effect of romosozumab is transient early stimulation of modeling-based bone formation on cancellous and endocortical surfaces; preclinical studies have demonstrated that romosozumab may affect changes in the remodeling unit resulting in positive bone balance. To further investigate the effects of romosozumab on bone balance, month 12 (M12) and M2 (to analyze early effects) unpaired bone biopsies from the FRAME clinical trial were analyzed using remodeling site reconstruction to assess whether positive changes in bone balance on cancellous/endocortical surfaces may contribute to the progressive improvement in bone mass/structure and reduced fracture risk in osteoporotic women at high fracture risk...

BACKGROUND: Knee osteoarthritis (KOA) is a common chronic degenerative joint disease. 3D printing technology has become one of the important directions of medical development along with individualized precision treatment in orthopedics. OBJECTIVE: To investigate the effect of 3D printing technology-assisted total knee arthroplasty (TKA) on cartilage in rabbits with KOA. METHODS: A rabbit model of KOA was established and treated by TKA or 3D printing-assisted TKA...

BACKGROUND: Assessing bone turnover in paediatric populations is crucial for understanding the physiological changes occurring during skeletal development and identifying potential abnormalities. The objective of this study was to assess osteocalcin (OC), bone alkaline phosphatase (BALP), and C-terminal telopeptide of type I collagen (CTX-I) levels reflecting bone formation and resorption for age and sex in Polish healthy children and adolescents. MATERIALS AND METHODS: A total of 355 healthy normal-weight children and adolescents (46...

Metastatic pelvic tumors pose a significant challenge in oncologic orthopedics due to their complex management and the high potential for postoperative complications. This case study discusses a 75-year-old male with a sacral stress fracture following a type 3 internal hemipelvectomy for a metastatic lesion from gastric cancer in the left pubic bone. Initial conservative treatments failed to yield satisfactory improvement, leading to surgical intervention. Open reduction and internal fixation with an iliosacral screw, despite complications, significantly alleviated pain and improved mobility...

BACKGROUND: Neutrophils rapidly accumulate in large numbers at sites of tissue damage, exhibiting not only their well-known bactericidal capabilities but also playing crucial roles in angiogenesis and tissue repair. While exosomes derived from human umbilical cord mesenchymal stem cells (HucMSC-Exo) have emerged as a promising therapeutic tool, their exact mechanisms of action remain partly elusive. We hypothesize that HucMSC-Exo treatment may modulate neutrophil phenotypes, thereby significantly influencing wound healing outcomes...

We describe a case of an Asian-Indian female patient who presented to us with abnormal fat accumulations in the torso and upper arms following indiscriminate use of corticosteroid and anabolic steroids for about 7 years. Despite prolonged steroid use, the patient did not display cushingoid phenotype or metabolic decompensation. Bone density, echocardiography, and ultrasonogram of the liver were also normal with no evidence of excess pericardial fat, hepatic steatosis, or peliosis hepatis. Concurrent use of anabolic androgen is thought to be protective against the ill effects of steroids, especially on the muscle and bone...

Osteoporosis after bariatric surgery is an increasing health concern as the rate of bariatric surgery has risen. In animal studies mimicking bariatric procedures, bone disease, together with decreased serum levels of Ca2+ , Mg2+ and the gastric hormone Ghrelin were described. Ghrelin regulates metabolism by binding to and activating the growth hormone secretagogue receptor (GHSR) which is also expressed in the kidney. As calcium and magnesium are key components of bone, we tested the hypothesis that Ghrelin-deficiency contributes to osteoporosis via reduced upregulation of the renal calcium channel TRPV5 and the heteromeric magnesium channel TRPM6/7...

Acute myeloid leukemia (AML) is a largely incurable disease, for which new treatments are urgently needed. While leukemogenesis occurs in the hypoxic bone marrow, the therapeutic tractability of the hypoxia-inducible factor (HIF) system remains undefined. Given that inactivation of HIF-1α/HIF-2α promotes AML, a possible clinical strategy is to target the HIF-prolyl hydroxylases (PHDs), which promote HIF-1α/HIF-2α degradation. Here, we reveal that genetic inactivation of Phd1/Phd2 hinders AML initiation and progression, without impacting normal hematopoiesis...

Although PTH is best known for its role as a regulator of skeletal remodelling and calcium homeostasis, more recent evidence supports a role for it in energy metabolism and other non-classical targets. In this report, we summarize evidence for an effect of PTH on adipocytes. This review is based upon all peer-reviewed papers, published in the English language with PubMed as the primary search engine. Recent preclinical studies have documented an effect of PTH to stimulate lipolysis in both adipocytes and liver cells and to cause browning of adipocytes...

PURPOSE: We investigated the incidence rates of a subsequent hip fracture (HF) and other subsequent fractures than HF after first incident HF, comparing patients with and without diabetes. METHODS: Using Danish medical databases, we identified 92,600 incident HF patients in the period 2004-2018. Diabetes exposure was examined overall, by type of diabetes (T2D and T1D), and by presence of diabetes complications. We estimated cumulative incidence of subsequent HFs and fractures other than HF within two years of the incident HF...

PURPOSE: There is some controversy regarding cytokines released from adipocytes, particularly adiponectin, leptin, and IL6 that regulate bone remodeling. In addition, IL6 is released from muscle contraction, which might have a distinct role in bone remodeling. Hence, this study investigated whether muscle contraction during a session of 40 min of high intensity interval training (40-min HIIT) and after 16 weeks of HIIT (16-wk HIIT) altered the release of those cytokines and bone remodeling in overweight women...

Spinal cord injury (SCI) triggers a complex cascade of events, including myelin loss, neuronal damage, neuroinflammation, and the accumulation of damaged cells and debris at the injury site. Infiltrating bone marrow derived macrophages (BMDMϕ) migrate to the epicenter of the SCI lesion, where they engulf cell debris including abundant myelin debris to become pro-inflammatory foamy macrophages (foamy Mϕ), participate neuroinflammation, and facilitate the progression of SCI. This study aimed to elucidate the cellular and molecular mechanisms underlying the functional changes in foamy Mϕ and their potential implications for SCI...

OBJECTIVE: We established an orthopedic ward fracture liaison services (OWFLS) model and evaluated its role in improving detection rates of bone metabolic markers, treatment rates, and long-term treatability. METHODS: This observational retrospective cohort study included 120 patients aged >50 years hospitalized for primary osteoporotic fracture from January 2018 to January 2019 (group A: not included in OWFLS). Group B (included in OWFLS) comprised 120 patients from February 2019 to February 2020...