Search Results (2,460)

Phosphorus (P) is a vital non-renewable macronutrient that is frequently immobilized by chemical fixation in acidic and calcareous soils. However, the specific transformation processes of different P sources across these different soil types remain poorly understood. A 120-day incubation experiment was conducted in a completely randomized design with three replicates using acidic and calcareous soils from Myanmar to evaluate six treatments: single superphosphate (SSP), diammonium phosphate (DAP), triple superphosphate (TSP), ammonium polyphosphate (APP), calcium phytate (CP), and an unfertilized control (CK). The modified Hedley fractionation method was employed to investigate the dynamic transformation of soil P fractions, the rate of available P transformation, and the relationship between soil transformation and soil P availability under different P-fertilizer sources. In both soils, SSP, DAP, and TSP provided high initial P release (249.7%, 239.9%, and 234.1%) in acidic soil and (159.5%, 170.8%, and 161.4%) calcareous soil, which peaked on day 10 compared to CK (p < 0.001) before rapidly declining. P transformation in calcareous soil declined more sharply than in acidic soil from the 10th day to the 15th day (especially in SSP and TSP, −11.3 and −16.9 mg kg⁻¹), indicating a higher rate of P immobilization in calcareous soil. Conversely, the delayed peak of APP (day 60) and the stability of CP indicate resistance to immediate soil fixation. Notably, overall effectiveness depended on soil type: SSP performed best in acidic soil and DAP in calcareous soil. Full article

The demineralization of tooth enamel is the primary consequence of dental caries, leading to cavities and finally tooth loss. Erosive tooth wear from acidic beverages and food is another factor that degrades enamel. In both cases, an acidic environment leads to etching and the final dissolution of tooth mineral, i.e., hydroxyapatite. Here, this process is discussed from a chemical perspective, taking into account the solubility of calcium phosphate and the presence of the pellicle (protein layer) and plaque (bacterial biofilms), which both affect the dissolution rate. While low pH is definitely decisive, calcium-binding ligands (e.g., acid anions, proteins) contribute to dissolution by removing calcium ions from the equilibrium. This is an important effect in the oral cavity where the concentration of biomolecules is high. The situation is complicated by the fact that the composition of saliva and the oral microbiome vary considerably between individuals. The state of current knowledge on the demineralization of enamel is summarized and discussed, also in the context of approaches to prevent dental caries and erosive tooth wear. Full article

Functional properties of caseins play a crucial role in the dairy industry, so it is important to develop methods to improve their functionality. The aim of this study is to investigate the combined effect of high-intensity ultrasound (HIUS) treatment and calcium chelation on functional properties of casein micelles. For this purpose, micellar casein concentrate (MCC) was prepared with a concentration of 3% (w/w) casein. Then, 0 and 10 mM of Disodium hydrogen phosphate was added. HIUS was performed at a frequency of 20 kHz, power intensity of 550 W/cm², and an amplitude of 100% for 0, 5, 10, 15, and 20 min at 25 °C. Factorial design was employed to investigate the effect of ultrasound time (UST) and disodium phosphate (DSP) on foam capacity (FC), emulsion activity index (EAI), gelation time (GT), G′ at 480 min of oscillation time (G′₄₈₀), slope of complex viscosity, and linear viscoelastic region (LVR). At 0 mM of DSP, increasing UST from 0 to 15 min decreased GT from 114.39 ± 3.20 to 83.52 ± 1.61 min, and it extended LVR from 40.36 ± 0.12 to 41.27 ± 0.27% of the applied strain. In addition, applying HIUS for 15 min increased the elasticity and firmness of MCC gel networks at 0 mM of DSP. G′₄₈₀ was not influenced by UST, but it was reduced by DSP from 108.40 ± 3.29 to 15.78 ± 1.58 Pa. Increasing both UST and DSP significantly increased FC from 110.00 ± 13.23 to 163.33 ± 11.55% and foam stability (FS) in all treatments. FS reached its maximum (doubled) after 10 min of UST at 0 mM of DSP. However, EAI and emulsion stability index (ESI) decreased with increasing both UST and DSP. HIUS treatment combined with calcium chelation might highlight a new approach to improve foaming properties. However, regardless of calcium chelation, HIUS treatment is a promising technology to improve the gelling properties of casein micelles. Full article

The combination of chemotherapy and immunotherapy represents a promising approach that leverages their complementary benefits. However, the side effects resulting from off-target effects and the low efficiency of immune activation remain a significant concern. Herein, we developed a zinc-doped calcium phosphate (ZCP) nanocarrier for the delivery of the chemotherapeutic drug doxorubicin (DOX). By further encapsulating whole proteins from 4T1 breast cancer cells, we constructed a novel nanodrug delivery system named ZCPDM. This system enables specific targeting of tumor cells and undergoes intracellular degradation to release DOX, Zn²⁺, and Ca²⁺. As a chemotherapeutic agent, DOX induces apoptosis while significantly elevating intracellular reactive oxygen species (ROS), thereby enhancing cytotoxicity. This leads to DNA damage and the release of chromosomal fragments. These DNA fragments, together with Zn²⁺, activate the cGAS-STING signaling pathway and trigger pyroptosis, which promotes more efficient recognition and clearance of tumor cells by the immune system. Through these dual mechanisms, ZCPDM effectively combines chemotherapy and immunotherapy. The anti-tumor efficacy and underlying mechanisms were validated at the cellular level. Furthermore, studies in tumor-bearing mice demonstrated its robust anti-tumor performance and ability to suppress tumor recurrence, along with good biosafety. This targeted drug delivery system achieves safe and synergistic chemo-immunotherapy through homologous targeting-mediated pyroptosis and activation of the cGAS-STING pathway, offering a novel and promising strategy for cancer treatment. Full article

Adsorption is a promising technology for phosphate removal to alleviate eutrophication. In this study, thermally modified calcium aluminate decahydrate (TCAH) was prepared via low-temperature thermal treatment of calcium aluminate decahydrate (CAH₁₀) to develop a cost-effective and high-performance phosphate adsorbent. The optimal modification temperature was determined to be 120 °C, which reduced the crystallinity of CAH₁₀, enhanced its porosity, and induced the formation of amorphous calcium aluminate phases. Batch adsorption experiments showed that TCAH exhibited a maximum adsorption capacity of 199.80 mg P/g at 25 °C. The adsorption kinetics followed the pseudo-second-order model, while the adsorption isotherms were well fitted by the Redlich–Peterson model. TCAH maintained high removal efficiency over a wide pH range of 3.0–11.0 and showed high selectivity against common coexisting anions. Characterizations using SEM-EDS, XRD, FTIR and XPS suggested that phosphate removal by TCAH was dominated by synergistic amorphous precipitation and inner-sphere complexation. In tests with real phosphorus-releasing liquor derived from excess sludge, TCAH achieved nearly complete phosphate removal at a dosage of 5 g/L within 6 h. Owing to its readily available raw materials, low preparation temperature, and outstanding phosphate capture performance, TCAH is a promising candidate for efficient phosphate capture and recovery from wastewater. Full article

Renal tubular disorders are often overlooked causes of acquired or inherited bone hypomineralization and fragility fractures in adults. The proximal tubule reabsorbs glucose, phosphate, low-molecular-weight proteins, amino acids, bicarbonate, and much of the sodium, potassium, chloride, and calcium. The distal nephron—the thick ascending limb of the loop of Henle, the distal convoluted tubule, and the collecting duct—regulates urine concentration and dilution, maintains acid-base balance via urinary proton secretion, and controls electrolytes, including sodium, potassium, magnesium, and calcium. Tubular defects may cause hyperphosphaturia (high urinary phosphate), hypercalciuria (high urinary calcium), or chronic metabolic acidosis (renal tubular acidosis, RTA). These changes weaken bone mineralization, disrupt bone turnover, and raise the risk of muscle weakness and fractures. This review summarizes acquired and genetic tubulopathies linked to hyperphosphaturia, hypercalciuria, and RTA and outlines a practical diagnostic approach for outpatients with bone fragility and suspected renal tubulopathy. Full article

Dental calculus is a highly prevalent oral condition in dogs and is widely recognized as an important risk factor for gingival inflammation and periodontal disease. Effective strategies for its prevention and treatment remain limited, highlighting the significance of exploring novel mechanisms underlying its formation. Neutrophil extracellular traps (NETs), a key component of innate immunity, have been found in various diseases. To investigate the relationship between NETs and canine dental calculus formation, NET-associated markers were assessed in the oral cavities of dogs with dental calculus and healthy controls. Based on previously published full-length 16S rRNA amplicon sequencing data of canine dental calculus, Porphyromonas gulae was selected as a candidate NET-inducing bacterium for subsequent validation experiments. Subsequent neutrophil stimulation experiments were conducted to explore the effects of NETs and related factors on dental calculus formation. Collectively, our findings demonstrate the presence of NETs within canine dental calculus and reveal that P. gulae present in canine dental calculus is capable of inducing NET formation. The level of myeloperoxidase–DNA complex in gingival crevicular fluid was significantly elevated in dogs with dental calculus. NETs promoted aggregation and microcrystal formation from calcium and phosphate ions under both physiological and supersaturated concentrations. By adhering to the surface of dental calculus, NETs facilitated calculus accumulation. This effect showed positive correlation with neutrophil counts and administration frequency, but was independent of the concentration of administered calcium and phosphate solutions. IL-1β promoted the formation of aggregated NETs but did not enhance calculus accumulation. DNase I inhibited this process by degrading NET-DNA. In conclusion, dental calculus and the calculus-inhabiting P. gulae could stimulate oral neutrophils to release NETs, which participate in and facilitate the initial formation, aggregation, and subsequent accumulation of canine dental calculus. Full article

Background/Objectives: Vitamin D, universally recognized for its role in calcium–phosphate homeostasis and skeletal health, has emerged as a key immuno-endocrine modulator. Its active metabolite interacts with the vitamin D receptor (VDR) across immune and endocrine cell populations, influencing gene transcription, cytokine balance, and immune tolerance. This narrative review synthesizes mechanistic, epidemiological, and clinical evidence on the role of vitamin D in immune modulation across autoimmune and infectious diseases. Methods: This narrative review incorporated a structured and comprehensive literature search across PubMed/MEDLINE, Scopus, Web of Science, Embase, and Google Scholar. Results: Vitamin D modulates both innate and adaptive immunity through antimicrobial peptide induction, macrophage and NK cell activation, and promotion of tolerogenic dendritic cells. Clinical and interventional trial outcomes remain heterogeneous and are influenced by baseline vitamin D status, dosing regimens, genetic variability, and disease context. Conclusions: Vitamin D functions in endocrine and immune regulation, contributing to host defense and immune tolerance. Current evidence supports that for autoimmune and infectious conditions, well-designed randomized trials are required to clarify effective dosing, identify responsive subpopulations, and elucidate genetic determinants of therapeutic benefit. Full article

The blue crab, Callinectes sapidus, is an invasive species in the Mediterranean Sea, where it has gained particular attention since 2023 due to its negative ecological and economic impacts. This study aimed to define a standardized method for hemolymph collection and biochemical analysis in male blue crabs from the northern Adriatic Sea, providing data on their physiological status. Hemolymph was collected following a standardized protocol. Preliminary validation tests showed good recovery, stability and linearity results for biochemical analytes, showing no significant analytical interference due to hemolymph pigmentation. Then, key biochemical variables, including glucose, calcium, magnesium, triglyceride, urea, uric acid, aspartate transaminase, gamma-glutamyl transferase, phosphate, potassium, sodium, chloride and total protein, were analyzed. The results revealed considerable variability in the biochemical profiles of the sampled individuals, consistent with the natural heterogeneity expected in a field-collected, mixed-molt cohort, while overall indicating a generally consistent euryhalinity, a good physiological status. The study underscores the importance of standardized protocols for hemolymph analysis in blue crab, contributing to the understanding of its physiology and invasive success. Full article

This prospective case series evaluated the short-term outcomes following percutaneous cementoplasty as the sole palliative treatment for appendicular osteosarcoma in 10 dogs. Synthetic self-hardening calcium phosphate bone substitute was injected into the osseous defect under fluoroscopic guidance after curettage of the bone tumor. Clinician assessment included a numerical rating score for lameness, offloading, and ease of lifting the contralateral limb as well as the 4A-VET postoperative pain scale. Owner assessment was obtained using three descriptive questionnaires, the Helsinki Chronic Pain Index (HCPI), the Canine Brief Pain Inventory (CBPI) and the Canine Symptom Assessment Scale (CSAS). Measures were recorded preoperatively and at 2, 4, 8, and 12 weeks following surgery. Early improvement in the 4A-Vet score was noted at the 2-, 4-, 8-, and 12-week time points for all major pain and function metrics. Similarly, the CBPI pain severity and interference scores demonstrated early postoperative improvement during the 2- and 4-week time points with partial attenuation by 8 and 12 weeks. Panting, difficulty sleeping, whining/moaning, and lack of appetite were significantly reduced when assessed via the CSAS. Cementoplasty as a monotherapy, affording early pain relief and improved structural integrity, supports its role as a palliative limb-preserving option for dogs unable to undergo amputation. Full article

Dental caries remains the most prevalent chronic disease worldwide, yet early enamel lesions are reversible if managed with appropriate remineralizing agents. This narrative review synthesizes current evidence on remineralizing agents, their mechanisms of action, and clinical applications, with a focus on dental materials used in preventive and minimally invasive dentistry. Traditional fluoride-based approaches enhance remineralization through fluorapatite formation; however, their effectiveness is limited when calcium and phosphate bioavailability is insufficient. Biomimetic agents, including casein phosphopeptide–amorphous calcium phosphate (CPP-ACP), bioactive glasses, tricalcium phosphate, and nano-hydroxyapatite, provide these bioavailable ions and demonstrate superior performance under challenging clinical conditions. Emerging therapies such as probiotics, photodynamic therapy, and laser-assisted mineralization show promise but require further clinical validation. Based on the primary mechanism of action, an original classification of remineralizing agents is proposed, grouping them into fluoride-based agents, calcium-phosphate systems, nanotechnology-based systems, biofilm modifiers, biomimetic and emerging systems, and adjunctive antimicrobial therapies. The review concludes that bioavailable calcium represents a critical limiting factor in remineralization under certain conditions, and that combination protocols incorporating multiple remineralizing agents, tailored to individual patient risk profiles, achieve superior outcomes compared to single-agent approaches. Clinicians are encouraged to adopt minimally invasive, patient-tailored remineralization strategies that arrest lesions before cavitation, preserving natural tooth structure and reducing the lifelong restorative burden. Full article

Background: The management of white spot caries lesions (WSCLs) presents a clinical challenge due to a lack of standardized protocols. This study aimed to evaluate the knowledge, attitudes, and practices of dental practitioners in Russia regarding the diagnosis and treatment of WSCLs. Methods: A cross-sectional online survey was conducted from October 2024 to July 2025 among 397 dental professionals in Russia. A validated questionnaire assessed four domains: demographics, knowledge, attitudes, and clinical practices concerning WSCL management. Data were analyzed using descriptive statistics, Kruskal–Wallis tests, and Spearman’s correlation. Results: The majority of respondents were females (83%), with over half having less than five years of experience (55%). A majority of the practitioners (62.5%) demonstrated a good level of knowledge (mean score 12.8 ± 2.2). Knowledge was significantly better among female practitioners (p < 0.001) and inversely correlated with years of clinical experience (p < 0.001). Attitudes towards minimally invasive treatment were mainly positive (mean score 13.5 ± 2.6), with 86% of respondents showing a positive score (>10 points). While awareness of minimally invasive techniques like resin infiltration (84%) and remineralization (79.1%) was high, clinical practice varied. Remineralization was the most frequently used treatment (68% used casein phosphopeptide–amorphous calcium phosphate and 62% used fluoride), whereas resin infiltration was used by 46% and microabrasion by only 5% of the respondents. A majority of dentists (52%) preferred monitoring lesions rather than immediate intervention. Conclusions: Russian dental practitioners possess good theoretical knowledge and positive attitudes toward contemporary, minimally invasive management of WSCLs. However, a significant gap exists between knowledge and clinical practice, particularly concerning the use of resin infiltration and microabrasion. These findings underscore the need for continuous education on the topic. Full article

This research reports on the properties of oxide-ceramic coatings produced by plasma electrolytic oxidation in novel electrolyte solutions for implantology applications. A series of bioactive calcium-phosphate coatings was synthesized on medical-grade Ti-13Zr-13Nb alloy using the plasma electrolytic oxidation (PEO) method. Novel electrolytes enriched with calcium and phosphorus were developed, enabling the formation of coatings with tailored physicochemical and structural characteristics. A correlation was established between the electrolyte composition and the phase composition, thickness, morphology, porosity, and microhardness of the resulting coatings. The optimum coatings exhibited a Ca/P ratio close to that of natural human bone tissue, homogeneity, a well-developed porous surface topography, and controlled resorption behavior. For the first time, a mechanism of calcium-phosphate coating resorption in a biologically active environment has been proposed. It involves partial dissolution, the formation of apatite-like surface structures, and the subsequent controlled release of Ca and P ions. In vitro testing in simulated body fluid indicated the potential bioactivity of the synthesized coatings. The proposed calcium-phosphate coatings may be considered promising candidates for future implant surface modification. The results obtained are significant for the development of advanced orthopedic and dental implants, including those fabricated using additive manufacturing technologies. Full article

Background: An increasing number of commercially available drug substances and bioactive ingredients are characterized by poor flowability. Inadequate flow properties may lead to material blockage during transport within production lines, as well as the formation of air voids within the bulk. Such phenomena can disrupt the technological process and may even result in batches that fail to meet quality requirements. Therefore, ensuring adequate powder flow is of utmost importance in the manufacture of health-related products. Methods: Binary mixtures were prepared using one of four model substances (ibuprofen, metamizole sodium, mefenamic acid, or sunflower lecithin) combined with a glidant (colloidal silica, precipitated silica, or tricalcium phosphate). The glidant content ranged from 0.5 to 10.0% w/w depending on the model substance, and mixing was carried out for 5–30 min. The resulting binary mixtures were evaluated for flow properties using the angle of repose method, and in selected cases, bulk density was also determined. Results/Conclusions: The study demonstrated that powder flow improvement depended not only on the glidant but primarily on the properties of the host material (particle size, shape, and bulk density). Coarser powders such as ibuprofen responded well to low glidant levels, although excessive silicon dioxide caused oversilication. Metamizole sodium showed progressively better flow with increasing particle size and density, and tribasic calcium phosphate further improved performance, particularly with longer mixing times. Very fine or cohesive powders, such as mefenamic acid and sunflower lecithin, showed limited response to silica-based glidants, whereas tribasic calcium phosphate proved more effective and additionally increased bulk density. Overall, no universal glidant strategy was identified; effective flow enhancement requires a tailored approach based on specific powder characteristics. Full article

Osteoarthritis (OA) is a highly prevalent joint disorder traditionally considered a consequence of mechanical cartilage wear; however, it is now recognized as a complex, multifactorial disease driven by interconnected molecular and cellular mechanisms. This narrative review synthesizes current knowledge on key pathogenic pathways underlying OA progression, with a focus on inflammatory signaling, subchondral bone remodeling, and dysregulation of mineral metabolism. Chronic low-grade inflammation promotes catabolic responses in chondrocytes and contributes to cartilage degradation. In addition, obesity influences OA pathogenesis through both biomechanical loading and adipokine-mediated inflammatory mechanisms. Alterations in the receptor activator of nuclear factor kappa-B/receptor activator of nuclear factor kappa-B ligand/osteoprotegerin (RANK/RANKL/OPG) axis disrupt bone homeostasis and promote pathological subchondral remodeling, while imbalances in inorganic phosphate metabolism contribute to crystal deposition and further joint damage. These processes interact synergistically, driving disease progression. Current therapeutic strategies remain largely symptomatic and do not adequately target underlying molecular drivers. A deeper understanding of these mechanisms may facilitate the development of disease-modifying therapies. Full article