Search Results (2,352)

Purpose: Hyperparathyroidism (HPT) is a condition marked by excessive secretion of parathyroid hormone (PTH), leading to disturbances in calcium, phosphate, and vitamin D metabolism. HPT is classified into primary (pHPT), secondary (sHPT), and tertiary (tHPT) types, which can cause systemic complications. Parathyroidectomy (PTX) remains the cornerstone treatment for pHPT and refractory cases of sHPT and tHPT. Methods: A retrospective review was conducted on 10 pediatric patients who underwent PTX for HPT at our clinic between 2016 and 2024. Demographic data, preoperative imaging, laboratory findings, surgical details, pathology reports, and postoperative outcomes were analyzed. Patients were categorized as having either pHPT (n = 6) or renal HPT (r-HPT; n = 4), which included one case of sHPT and three cases of tHPT. Results: The mean age of pHPT and r-HPT patients was 15 and 13 years, respectively. While 50% of pHPT patients were female, all r-HPT patients were female. Preoperative imaging localized parathyroid lesions using ultrasonography in all cases, but Sestamibi scintigraphy had a lower detection rate (66.7%). Minimally invasive parathyroidectomy was performed in single-gland pHPT cases, while bilateral neck exploration was used for multiglandular pHPT and all r-HPT cases. No intraoperative complications were observed. Postoperatively, all patients demonstrated normalized calcium, phosphate, and PTH levels with significant symptomatic improvement. Hungry bone syndrome developed in one r-HPT patient and was managed successfully. No recurrences were noted during an average follow-up of 39 months. Conclusions: PTX is a safe and effective treatment for pediatric HPT, providing excellent biochemical and clinical outcomes. Multidisciplinary collaboration is crucial in managing pediatric cases, particularly those with complex renal HPT. Full article

Phosphate is emerging as an active mediator of oxidative stress and vascular injury in chronic kidney disease (CKD). This emerging pathophysiological framework, referred to as “Phosphatopathy”, describes the systemic syndrome driven by chronic phosphate overload and characterized by oxidative stress, inflammation, endothelial dysfunction, vascular calcification, cellular senescence, and metabolic imbalance. Beyond being a biochemical marker, phosphate overload triggers NOX-derived reactive oxygen species (ROS), activates Wnt/β-catenin and TGF-β signaling, and disrupts the FGF23–Klotho axis, promoting endothelial dysfunction, vascular calcification, and left ventricular hypertrophy (LVH). These pathways converge with systemic inflammation and energy imbalance, contributing to the malnutrition–inflammation–atherosclerosis (MIA) syndrome. Experimental and clinical data reveal that the phosphate/urinary urea nitrogen (P/UUN) ratio is a sensitive biomarker of inorganic phosphate load, while emerging regulators such as microRNA-125b and calciprotein particles integrate phosphate-driven oxidative and inflammatory responses. Therapeutic strategies targeting phosphate burden—rather than serum phosphate alone—include dietary restriction of inorganic phosphate, non-calcium binders, magnesium and zinc supplementation, and activation of important pathways related to the activation of antioxidant defense such as AMP-activated protein kinase (AMPK) and SIRT1. This integrative framework redefines phosphate as a modifiable upstream trigger of oxidative and metabolic stress in CKD. Controlling phosphate load and redox imbalance emerges as a convergent strategy to prevent vascular calcification, improve arterial stiffness, and reduce cardiovascular risk through personalized, mechanism-based interventions. Full article

This study aimed to develop a sustainable route for processing biogenic calcium carbonate from Perna perna mussel shell waste and converting it into hydroxyapatite (HA), as well as to evaluate its potential for bone and dental tissue engineering applications. Mussel shells were decarbonized (400 °C), milled, and converted to HA via wet chemical precipitation using a nominal Ca/P molar ratio of 1.67 during synthesis followed by thermal treatment (900 °C). Comprehensive characterization included SEM, FTIR, XRD, Raman spectroscopy, XRF, TGA, and BET analysis. Biological evaluation involved cytotoxicity assays (MTT), antimicrobial testing, and odontogenic differentiation studies (Alizarin Red) using SHEDs. Statistical analysis by one-way ANOVA and Tukey post hoc tests (α = 0.05). SEM revealed a microstructured morphology composed of agglomerates, favorable for biomedical applications. FTIR and XRD confirmed the conversion of CaCO₃ to hydroxyapatite, while thermal analysis demonstrated the material’s stability. The HA exhibited secondary minor phase (13%) β-TCP form of calcium phosphate (Ca_2.997H_0.006(PO₄)₂), high crystallinity (about 80%), and nanoscale crystallite size (85 nm, 2.5–5.0 m²/g), despite forming larger agglomerates in suspension. The material showed favorable physicochemical properties (neutral pH, −18.5 mV zeta potential), but no inhibition was detected in antimicrobial testing. In vitro assays showed excellent cytocompatibility (viability > 70% at 12.5 µg/mL) and significant osteogenic potential (high mineralization vs. controls, p < 0.05). Mussel shell-derived HA presents a sustainable, clinically relevant biomaterial with ideal properties for bone regeneration. The study establishes a complete waste-to-biomaterial pipeline while addressing key requirements for dental and orthopedic applications. Full article

This study investigates the adaptive mechanisms that enable a single wild barley (Hordeum spontaneum) accession to withstand extreme salinity. Salt stress reshapes plant metabolism and gene expression, offering targets for breeding salt-tolerant cereals. A time-course RNA-Seq experiment was conducted on leaves exposed to 500 mM NaCl, followed by differential expression and functional annotations to characterize transcriptomic responses. Transcriptomic profiling identified 140 dynamically upregulated genes distributed across 19 interconnected metabolic pathways, with phased activation of oxidative phosphorylation, nitrogen assimilation, lipid remodeling, and glutathione metabolism. Central metabolic nodes, including acetyl-CoA, hexadecanoyl-CoA, and ubiquinone, coordinated bioenergetic output, membrane stabilization, and redox homeostasis. Ribose-5-phosphate and ribulose-5-phosphate linked glycolysis and the pentose phosphate pathway, supplying NADPH for antioxidant defense and nucleotide repair, while riboflavin derived from Ru5P enhanced flavoprotein activity. In parallel, glucose and fructose-6-phosphate supported osmotic adjustment and glycolytic flux, and increased sterol and cuticular lipid biosynthesis, including cholesterol-like compounds, reinforced membrane integrity and calcium signaling. Glutathione and N-acetyl-glutamate together mitigated oxidative stress and modulated polyamine metabolism, strengthening cellular resilience under salt stress. These findings outline a coordinated network of metabolic and redox pathways that can guide the engineering of salt-tolerant cereals for sustainable production in saline agroecosystems. Full article

Tricalcium phosphate (TCP) bioceramics, available as α- and β-polymorphs, are frequently employed in the production of three-dimensionally (3D) printed bone scaffolds. Although hydrothermal immersion processing (HP) and sintering (S) are commonly adopted as post-printing techniques for bioceramics, a comprehensive comparative analysis of their effects on the osteogenic performance of α- and β-polymorphs in vivo remains inadequately investigated. In this study, α-TCP and β-TCP scaffolds were fabricated via direct ink writing and subjected to hydrothermal immersion processing (α-TCP/HP) and sintering (β-TCP/S) prior to implantation in n = 12 skeletally mature sheep (n = 1 scaffold per group per animal), and the outcome variables were evaluated at 3 and 12 weeks postoperatively (n = 6 sheep per time point). The quantitative results showed no significant differences in bone deposition or scaffold resorption at 3 weeks postoperatively (p = 0.618 and p = 0.898, respectively). However, at 12 weeks, there was a significant increase in osteogenesis and scaffold resorption in the β-TCP/S cohort relative to the α-TCP/HP counterparts (p < 0.001 and p = 0.004, respectively). β-TCP scaffolds subjected to post-print sintering exhibited superior osteoconductive and resorptive profiles compared to hydrothermal immersion-processed α-TCP scaffolds over the 12-week healing period. Full article

Pigment gallstones represent a heterogeneous group of concretions, classically divided into black and brown types, whose morphology and microstructure offer critical clues about their underlying pathogenesis. Gallstone formation (lithogenesis) is a complex process triggered when the physicochemical equilibrium of bile is disrupted. Background/Objectives: The spicules observed on the surface of certain black pigment gallstones have traditionally been attributed to the branching capacity of cross-linked bilirubin polymers. However, a growing body of experimental and spectroscopic evidence suggests that inorganic calcium salts, particularly calcium carbonate and calcium phosphate, play a central role in the formation of the distinctive spiculated or “coral-like” architecture. Materials and Methods: In our study, we examined a case series of 1350 consecutive patients with gallstone disease, identifying 81 patients who presented with solitary black pigment stones. We systematically explored the association between high calcium content, specifically calcium carbonate, and the occurrence of spiculated morphology. Our analyses demonstrated a robust correlation between an elevated concentration of calcium carbonate and the presence of well-defined spicules. Results: These results support the hypothesis that mineral elements, rather than organic bilirubin polymers, act as crucial determinants of the peculiar crystalline structure observed in a significant subset of pigment stones. Spiculated stones, due to their small size and sharp projections, have a higher likelihood of migrating, increasing the risk of potentially life-threatening complications, such as acute cholangitis and gallstone pancreatitis. Conclusions: Our findings, consistent with recent advanced crystallographic analyses, underscore the importance of considering mineral composition in the diagnosis and management of cholelithiasis. Understanding the factors that drive calcium carbonate precipitation is essential for developing new preventive and therapeutic strategies, aiming to modulate bile chemistry and reduce the risk of calcium-driven lithogenesis. Full article

Urine is historically the oldest biological material used for diagnostic purposes. Urine testing dates to the ancient Babylonians and Sumerians. Uroscopy consisted of visual and organoleptic assessment (color, clarity, odor, taste testing) of urine. Its principles did not change until the Age of Enlightenment. In the 16th century, when the first microscope was constructed, uroscopy was enriched with the assessment of urine sediment. As chemical methods have developed, tests for various analytes in urine have been introduced into diagnostic methods. The presence of sugar and protein and excretion of urea, creatinine, uric acid and electrolytes, such as sodium, potassium, chlorides, calcium, and magnesium and phosphates, were assessed. Over the years, the set of tests performed on urine has changed, among others, due to the possibility of performing more diagnostically reliable tests in blood. Although currently the most common material for laboratory tests is blood, a general urine test has not lost its importance, and it is a widely performed screening test. Full article

Calcium magnesium phosphate cements (CMPCs) were obtained starting from dolomite (alone or mixed with fly ash) thermally treated at two different temperatures. Dolomite calcination at 750 °C for 3 h determined the formation of a mixture of MgO and CaCO₃. The mixing of dolomite with fly ash and the increase in the calcination temperature at 1200 °C determined the formation of new compounds (calcium aluminum silicate and calcium magnesium silicates), which are present along with MgO and small amounts of CaO in the thermally treated material. These two precursors were mixed with KH₂PO₄ solution and borax (as a retardant admixture) to obtain the CMPCs. The setting time and compressive strengths of these CMPCs were assessed and the XRD analyses provided insights into their mineralogical composition after hardening and thermal treatment. The cements, as so or mixed with perlite, were applied on steel plates, to assess their behavior when put in direct contact with a flame. The compatibility of these materials with the steel substrate was evaluated by scanning electron microscopy (SEM). The direct contact with the flame up to 60 min provided information regarding the CMPCs’ ability to prevent the rapid increase in the substrate (steel plate) temperature. The findings indicate that CMPC pastes and composites containing perlite can offer a degree of protection for steel structures in the event of a fire. Full article

Conventional dental materials with organised crystal structures exhibit limitations in corrosion resistance, bioactivity, and drug delivery capability. In contrast, amorphous nanomaterials offer potential advantages in overcoming these limitations due to their unique structural properties. They are characterised by a non-crystalline, disordered atomic structure and are similar to a solidified liquid at the nanoscale. Among the amorphous nanomaterials used in dentistry, there are five major categories: calcium-, silicon-, magnesium-, zirconia-, and polymer-based systems. This study reviewed these amorphous nanomaterials by investigating their synthesis, properties, applications, limitations, and future directions in dentistry. These amorphous nanomaterials are synthesised primarily through low-temperature methods, including sol–gel processes, rapid precipitation, and electrochemical etching, which prevent atomic arrangements into crystalline structures. The resulting disordered atomic configuration confers exceptional properties, including enhanced solubility, superior drug-loading capacity, high surface reactivity, and controlled biodegradability. These characteristics enable diverse dental applications. Calcium-based amorphous nanomaterials, particularly amorphous calcium phosphate, demonstrate the ability to remineralise tooth enamel. Silicon-based amorphous nanomaterials function as carriers that can release antibacterial agents in response to stimuli. Magnesium-based amorphous nanomaterials are antibacterial and support natural bone regeneration. Zirconia-based amorphous nanomaterials strengthen the mechanical properties of restorative materials. Polymer-based amorphous nanomaterials enable controlled release of medications over extended periods. Despite the advances in these amorphous nanomaterials, there are limitations regarding material stability over time, precise control of degradation rates in the oral environment, and the development of reliable large-scale manufacturing processes. Researchers are creating smart materials that respond to specific oral conditions and developing hybrid systems that combine the strengths of different nanomaterials. In summary, amorphous nanomaterials hold great promise for advancing dental treatments through their unique properties and versatile applications. Clinically, these materials could improve the durability, bioactivity, and targeted drug delivery in dental restorations and therapies, leading to better patient outcomes. Full article

The aim of the study was to investigate the synergistic effect of conditioned medium (CM) and two types of calcium phosphate biocements on the osteogenic properties of a composite material through rat bone marrow-derived mesenchymal stem cells (MSCs). Briefly, MSCs were cultured for 7 and 17 days in extracts derived from the two biocement types. These extracts were supplemented with 5% (v/v) of concentrated CM. The CM was obtained from rat bone marrow MSC cultures after a 48 h conditioning period. The results showed that the addition of CM had a significant positive impact on the osteoblastic differentiation of MSCs, particularly in the extracts from the tetracalcium phosphate/monetite/calcium sulfate hemihydrate biocement (designated as CAS cement) compared to the other tested cement extract (designated C cement). After 17 days of culturing, a notable increase in cell viability and alkaline phosphatase (ALP) activity, as well as the upregulation of osteoblastic-related gene expression, was found. This enhancement in osteogenic activity was likely driven by the growth factors and bioactive molecules present in the CM. The study concluded that supplementing the biocement extracts with only 5% of 10X concentrated CM is sufficient to significantly influence and improve the in vitro characteristics, cell behavior, gene expression, and synthesis of cell products. It was demonstrated that, especially in the CAS supplemented with CM (CAS + CM) extract system, the improvement in osteogenic properties was due to the synergistic effect between the higher concentration of calcium ions in extracts released from the calcium sulfate hemihydrate-containing cement and the bioactive molecules supplied by the CM. Full article

Tooth extraction induces changes in both hard and soft tissues, which may compromise implant placement. Leukocyte- and platelet-rich fibrin (L-PRF) is used to promote tissue healing, either alone or in combination with other grafting materials. Objective: This study aimed to compare post-extraction socket healing using L-PRF alone or combined with a biphasic calcium phosphate graft (HA/β-TCP) after eight weeks. Materials and Methods: 15 patients, both sexes, mean age 56.7 ± 8.2 years, requiring alveolar ridge preservation after single-rooted tooth extraction for subsequent implant placement, were included. Sockets were randomly assigned to four groups: control with blood clot only (CTR), autogenous bone graft (AB), L-PRF membrane (LPRF), and L-PRF combined with HA/β-TCP (LPRFHA). The protocol consisted of tooth extraction and immediate graft placement, followed by bone biopsy at 8 weeks for histomorphometric analysis and implant installation. New Bone Formation (NBF) was quantified from ten photomicrographs per sample using ImageJ software (version 1.54, 5 February 2025). One-way ANOVA with Bonferroni post hoc tests was applied, with statistical significance set at p ≤ 0.05. Results: A significant difference in NBF (%) was observed between the control and LPRFHA groups (p = 0.014), with greater bone formation in the control group (62.4 ± 18.6%) compared with LPRFHA (55.8 ± 17.2%; p = 0.012). No significant differences were found among AB, LPRF, and LPRFHA groups. LPRF and AB showed comparable bone formation (60.2 ± 17.5% and 60.1 ± 20.0%, respectively). Conclusions: L-PRF, either alone or combined with HA/β-TCP, can be used for alveolar ridge preservation in maxillary sockets. L-PRF, alone or with synthetic HA/β-TCP graft, effectively preserves the anterior maxillary ridge for early loading at eight weeks. All treatments achieved bone formation for implant placement, with the blood clot alone showing superior results. Full article

Background/Objectives: Chronic bone infections require local antimicrobial delivery to achieve high drug concentrations while limiting systemic toxicity. Silver ion-doped calcium phosphate synthetic bone grafts have been proposed as carriers for local antimicrobial release. This study aimed to evaluate the efficacy and safety of a silver ion-doped synthetic bone graft in patients with chronic osteomyelitis, infected nonunion, or implant-related bone infection. Methods: This retrospective cohort included 12 adults who underwent surgery for chronic osteomyelitis or implant-associated infection. All patients received thorough debridement, removal of infected implants when present, and filling of bone defects with a silver ion-doped calcium phosphate graft. The median age was 38 years, and follow-up was 12 months. Clinical and radiographic outcomes, liver and kidney function tests, and blood silver levels were assessed pre- and postoperatively. Results: Infection eradication was achieved in 11 of 12 patients (90%) at 12 months. Functional recovery, defined as return to normal daily activities, occurred within 3–5 months. Bone union was observed in all but one patient within 3–6 months, and no graft resorption was detected at one year. No significant differences in liver or kidney function tests were found compared with the control group (p > 0.05), and blood silver levels remained within normal limits. Conclusions: At 12-month follow-up, silver ion-doped synthetic bone grafts showed encouraging safety and efficacy in the treatment of chronic osteomyelitis. These findings suggest that silver-doped grafts may represent a useful option for one-stage treatment of osteomyelitis. Full article

Background and Objectives: Sjögren’s syndrome (SS) causes destructive salivary gland dysfunction with substantial oral morbidity. To synthesize practical, evidence-based approaches for early recognition, initial oral management, and timely referral to dental care. Materials and Methods: Narrative review of English-language literature from the Web of Science Core Collection and PubMed, prioritizing systematic reviews, randomized trials, and consensus guidelines. Results: Early oral signs include rapid multifocal root and cervical caries, burning sensations, and rising dental treatment needs. Unstimulated whole saliva ≤ 0.1 mL/min supports significant hypofunction and complements the 2016 ACR/EULAR criteria. Preventive care should combine dietary counseling, salivary stimulation, and topical remineralization. Adjuncts include high-fluoride toothpaste, biomimetic hydroxyapatite dentifrices, and casein phosphopeptide–amorphous calcium phosphate (CPP-ACP). However, evidence for fluoride varnish in SS remains mixed. Pharmacologic sialogogues require screening for contraindications. Conclusions: Embedding oral screening, simple salivary metrics, and a structured referral pathway into rheumatology visits can reduce preventable tooth loss and improve comfort, function, and treatment adherence. Full article

The overuse of chemical fertilizers can result in elevated concentrations of nitrogen (N) and phosphorus (P) in soil, potentially impacting rock weathering processes and carbon flux in karst regions. This study analyzed the impacts of chicken dung fertilizer and compound fertilizer on the weathering of carbonate rocks within the water-soil-rock system, yielding the following results: (1) The peak concentrations of various ions in the compound fertilizer system (Ca²⁺: 36.8 mg/L, Mg²⁺: 4.3 mg/L, N: 284.2 mg/L, P: 920.6 mg/L, HCO₃⁻: 16,170.3 mg/L) were generally superior to those in the chicken manure fertilizer system (15.4 mg/L, 1.9 mg/L, 306.9 mg/L, 27.9 mg/L, and 4576.5 mg/L, respectively), with a difference of approximately fourfold between the two systems; (2) Nitric acid generated by nitrification in fertilizers and phosphoric acid in compound fertilizers modify the chemical equilibrium of rock weathering, enhance dissolution, and influence the dynamics of HCO₃⁻; (3) Nitrogen and phosphorus in compound fertilizers are predominantly eliminated through ion exchange and adsorption. Calcium-phosphate precipitates are generated on the limestone surface within the 20 cm soil column, exhibiting a greater degree of weathering compared to the chicken manure fertilizer treatment; (4) analyses utilizing XRD, FT-IR, XPS, SEM, and additional approaches verified that substantial weathering and surface precipitation transpired on limestone throughout the 20 cm compound fertilizer column. Full article

Metallic implants used in orthopedics, such as titanium alloys, possess excellent mechanical strength but suffer from corrosion and poor bio-integration, often necessitating revision surgeries. Bioactive coatings, particularly hydroxyapatite, can enhance implant osteoconductivity, but high-purity synthetic hydroxyapatite is costly. This study investigates the development and characterization of a low-cost, biocompatible coating using hydroxyapatite derived from an unconventional natural source dromedary bone applied onto a titanium substrate via plasma spraying. Hydroxyapatite powder was synthesized from dromedary femurs through a thermal treatment process at 1000 °C. The resulting powder was then deposited onto a sandblasted titanium dioxide substrate using an atmospheric plasma spray technique. The physicochemical, structural, and morphological properties of both the source powder and the final coating were comprehensively analyzed using Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, X-ray Diffraction, and Fourier-Transform Infrared Spectroscopy. Characterization of the powder confirmed the successful synthesis of pure, crystalline hydroxyapatite, with Fourier-Transform Infrared Spectroscopy analysis verifying the complete removal of organic matter. The plasma-sprayed coating exhibited good adhesion and a homogenous, lamellar microstructure typical of thermal spray processes, with an average thickness of approximately 95 μm. X-ray Diffraction analysis of the coating revealed that while hydroxyapatite remained the primary phase, partial decomposition occurred during spraying, leading to the formation of secondary phases, including tricalcium phosphate and calcium oxide. Scanning Electron Microscopy imaging showed a porous surface composed of fully and partially melted particles, a feature potentially beneficial for bone integration. The findings demonstrate that dromedary bone is a viable and low-cost precursor for producing bioactive hydroxyapatite coatings for orthopedic implants. The plasma spray method successfully creates a well-adhered, porous coating, though process-induced phase changes must be considered for biomedical applications. Full article