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Writing the Initial Parenteral Nutrition Order
Published in Michael M. Rothkopf, Jennifer C. Johnson, Optimizing Metabolic Status for the Hospitalized Patient, 2023
Michael M. Rothkopf, Jennifer C. Johnson
From the prescriber’s perspective, we should recognize that the risk of calcium phosphate precipitation increases as the combined content of calcium and phosphorus increases. This is especially true when the PN volume decreases. As a rule of thumb, try to keep the sum of both to less than 45 (RxKinetics 2009). You can calculate the calcium/phosphorus solubility product by multiplying the total calcium added (in mEq) times the total phosphate used (in mmol) and dividing by the number of liters of final PN volume. The equation looks like this: Calcium/phosphorus solubility product = Total PN Ca++(mEq) × Total PN PO4 (mmol)/Total PN Volume (liters)
Bioceramic Nanoparticles for Tissue Engineering
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Nanosized bioceramic particles of calcium phosphates (CaPs) like nano-hydroxyapatite (nHAp) and nano-tricalcium phosphates (nTCP) have obtained specific interest in the development of biomaterials used for clinical applications specifically as restorative dental and orthopaedic implants. Different compounds of calcium phosphates such as hydroxyapatite (HAp), calcium tetraphosphate (Ca4P2O9), tricalcium phosphate (TCP) Ca3(PO4)2, and calcium hydroxyapatite Ca10(PO4)6(OH)2 can be produced by varying the atomic ratio of Ca/P from 1.5 to 2 (Ramay and Zhang 2004). Since the structure of calcium phosphate resembles the inorganic component of natural hard tissue, i.e. bone and teeth, and also they have typical biological responses such as good bioaffinity and enhancement of osseo-integration as well as successful clinical history, these ceramics are in high demand in the clinical field (Ebrahimi et al. 2019). However, the biological performance such as protein adsorption, angiogenesis, and vascularisation will totally depend on CaP particle composition, structure, morphology, and crystallite sizes (Zhou et al. 2013). Also, calcium phosphates are soluble under aqueous solution below pH 4.2, the property which makes it exploited during resorption of bone mineral by osteoclasts (bone remodelling) leading to the conditions of lysosomal degradation. Therefore, calcium phosphate nanoceramics are often applied for making scaffolds for solid bone tissue engineering (Ebrahimi et al. 2019).
Bio-Ceramics for Tissue Engineering
Published in Naznin Sultana, Sanchita Bandyopadhyay-Ghosh, Chin Fhong Soon, Tissue Engineering Strategies for Organ Regeneration, 2020
Hasan Zuhudi Abdullah, Te Chuan Lee, Maizlinda Izwana Idris, Mohamad Ali Selimin
Calcium phosphate (CaP) has been used widely in biomedical applications due to its capability in mimicking the properties of natural bone (Table 8.4). It has been used in the formation of artificial bone (bone-graft) or as a bioactive coating on other biomaterials especially those made from bioinert metals for orthopaedic as well as orthodontic applications (Legeros et al. 2009). CaP can be observed naturally in biological systems. CaP has been synthesized and used to manufacture various forms of implants, as well as for solid and porous coating on other implants. It is necessary to mention that different phases of CaP exhibit different solubility coefficients and these are dependent on temperature, pH, and environmental composition (Shadanbaz and Dias 2012).
Oridonin-loaded lipid-coated calcium phosphate nanoparticles: preparation, characterization, and application in A549 lung cancer
Published in Pharmaceutical Development and Technology, 2022
Calcium phosphate belongs to the ‘generally recognized as safe’ (GRAS) substances outlined by the U.S. Food and Drug Administration (FDA) (Roy et al. 2003). Calcium phosphate bone cement was previously prepared with embedded anticancer agent 6-mercaptopurine (6-MP) and showed sustained release characteristics (Otsuka et al. 1994). In normal metabolism, the concentration of calcium phosphate in the blood is estimated to be 1–5 mM (Muddana et al. 2009). This is the biological tolerance limit for the use of calcium phosphate as an effective carrier for real-time treatment strategies (He et al. 2002). Other carriers have completely failed in clinical trials. In addition, calcium phosphate nanoparticles are delivered locally and controlled in various ways. Their cost-effective preparation, high bioavailability, increased chemical stability, stimulation reactivity, pH dependence, surface engineering properties, low or no antigenicity (Senapati et al. 2018), and water solubility can improve therapeutic effects. The application of calcium phosphate nanoparticles in biomedicine has been extended to tissue engineering, gene/siRNA delivery, anticancer drug delivery, protein and antigen delivery, vaccine delivery, insulin, and imaging probe or contrast agent delivery for biological imaging. The lipid calcium phosphate nanoparticles (LCPs) can also be conjugated with targeting ligands, such as anisamide (AS), a molecule specific to the sigma receptor over-expressed in lung cancer cells.
Calcium-phosphate homeostasis in secondary progressive multiple sclerosis patients during mitoxantrone therapy
Published in Neurological Research, 2021
Martyna Lis, Natalia Niedziela, Maria Nowak-Kiczmer, Katarzyna Kubicka-Bączyk, Monika Adamczyk-Sowa
In our study, patients had low ionized calcium levels (Ca2+) initially, most likely due to lower levels of VitD, which is involved in regulating the concentration of Ca2+ in the body. Moreover, this concentration was also decreased in the further follow-up after introducing VitD supplementation. This finding is in line with other studies that found reduced Ca2+ concentration with disease duration, and additionally an increase during relapses [20]. However Golan et al. reported that Ca2+ concentration was stable within normal range after supplementation with high and low doses [22]. We observed no significant differences between the concentrations of other parameters of calcium-phosphate metabolism at the beginning and at the end of our study despite VitD treatment. The level of PTH was elevated. In their study, Golan et al. found that PTH was decreased after high doses of VitD. However, no significant changes were observed after administration of low doses. This hormone is suspected to have an anti-inflammatory function. There are also studies that do not support its immunomodulatory role, whilst others reports find that PTH is increased during MS relapse [22].
Advances in pharmacotherapy for diabetic foot osteomyelitis
Published in Expert Opinion on Pharmacotherapy, 2021
Raju Ahluwalia, Jose Luiz Lázaro-Martínez, Ines Reichert, Nicola Maffulli
The principal types of biodegradable ceramics available for antibiotic delivery are based on either calcium sulfate or calcium phosphate (Tables 4 and 5). Within the calcium phosphate group, two main types exist: tricalcium phosphate and hydroxyapatite. Calcium sulfate has also been used as a bone graft material since 1892 [90], having a compressive strength equivalent to that of cancellous bone [91]. However, it is brittle and quickly loses its strength as it is hydrolyzed on its own and needs to be combined with another ceramic. Its use in DFO showed that 20 of 323 patients required further debridement before wound healing occurred [92], and another 20 patients required an amputation, 6 being below knee. Jogia et al. reported no recurrence or amputation following debridement of forefoot ulcers in 20 patients at 12-month follow-up with routine use of calcium sulfate impregnated with antibiotics [93]. Krause et al. found that 13 of 49 feet treated by trans-metatarsal amputation with calcium sulfate and tobramycin experienced a reduction in below knee amputation rates at an average follow-up of 28 months (8–52 months) [94].