China 
Africa 
Explore chapters and articles related to this topic
Medicine
Published in Seema Khan, Get Through, 2020
Oxalate stones are common in Crohn’s disease; this patient also consumes a diet high in this salt. In Crohn’s disease, fat malabsorption leads to high levels of fatty acids within the colon; these bind to calcium ions leaving high levels of oxalate ions available for absorption (instead of being excreted in the faeces). Hyperoxaluria occurs and crystallization causes stone formation.
Lipid-Based Nanoparticles: SLN, NLC, and MAD
Published in Madhu Gupta, Durgesh Nandini Chauhan, Vikas Sharma, Nagendra Singh Chauhan, Novel Drug Delivery Systems for Phytoconstituents, 2020
Rita Cortesi, Paolo Mariani, Markus Drechsler, Elisabetta Esposito
NLC are the second generation of SLN dispersed in an aqueous medium. The difference with the SLN is based on the use of a more homogeneous lipid matrix obtained by the use of liquid lipids mixed with solid lipids (Jores et al., 2004, Müller et al., 2002). As above, reported liquid lipids can load to drugs better than solid lipids, thus, a mixture of liquid and solid lipids provides a high incorporation capacity. Indeed, the differences in structure between a solid and a liquid lipid create a lot of imperfections able to accommodate the drug (Pardeike et al., 2009). Notably, it is possible to obtain three NLC patterns, namely imperfect, amorphous, and multiple (Muller et al., 2002a). As above described, the process of SLN drug loading occurs during the formation of lipid crystals. The crystallization process allows the production of a perfect crystal, and during time it causes drug expulsion. By avoiding the crystallization process, it is possible to increase the number of imperfections in the crystal of NLC matrix and thus the drug loading. In this way during the storage, the rapid drug expulsion phenomenon observed in SLN is controlled in NLC that are not crystalline.
Nephrolithiasis: etiology, stone composition, medical management, and prevention
Published in J Kellogg Parsons, E James Wright, The Brady Urology Manual, 2019
Crystallization: Stones are essentially salts that precipitate out of urineThe point of saturation of a salt in solution is called the solubility product (Ksp)When the product of the components of a salt (e.g. calcium and oxalate) exceeds Ksp, salt crystals will precipitate out of solutionCrystallization is based on Ksp, pH, and the presence of stone inhibitors and promotersSome stone inhibitors increase the concentration of stone components required for the crystals to precipitate out of solution (i.e. for the stone crystals to form).
Preparation and characterization of indomethacin loaded films by piezoelectric inkjet printing: a personalized medication approach
Published in Pharmaceutical Development and Technology, 2020
Muhammad Sohail Arshad, Aqeel Shahzad, Nasir Abbas, Ali AlAsiri, Amjad Hussain, Israfil Kucuk, M.-W. Chang, Nadeem Irfan Bukhari, Zeeshan Ahmad
Image analysis studies of IMC gave a clear description that how the drug was delivered. The phenomena of crystallization were clearly observed in this study. Images derived from electron microscopy, plane polarized microscopy, and light microscopy showed evident crystal growth. The change in number and shape of crystals at varying DPIs could also be observed here. This study explored the use of PVP to alter the rate of dissolution. Polyvinylpyrrolidone was used with type B ink which was printed in the same design (same DPIs and sheets). Image analysis showed that addition of PVP affected the crystals growth in these formulations and indicated that the PVP interacted with crystal growth. SEM, plane polarized, and light microscopy images clearly presented a pattern in which crystals of IMC were surrounded by polymer molecules and the phenomenon of caging could be observed.
Effect of Soluplus on the supersaturation and absorption of tacrolimus formulated as inclusion complex with dimethyl-β-cyclodextrin
Published in Pharmaceutical Development and Technology, 2019
Chun Tao, Taotao Huo, Qian Zhang, Hongtao Song
In this study, the influence of Soluplus toward the FK506 inclusion complex was investigated. Preparation of FK506-CD with DM-β-CD remarkably improved the dissolution of FK506. But severe drug crystallization was observed in supersaturated condition. The addition of 1.2% Soluplus best enhanced the supersaturated stability of FK506. Moreover, the Soluplus also reduced drug crystallization and degradation in the stress test. The intestinal perfusion and pharmacokinetic study revealed that the in vivo absorption of FK506 was enhanced by Soluplus. The bioavailability of FK506-SCD was 2.34-fold that of FK506-CD. Our findings suggested that Soluplus had an excellent capability in improving the supersaturated stability of FK506 inclusion complex, which further promoted the in vivo drug absorption.
Anti-hyperuricemic property of 6-shogaol via self-micro emulsifying drug delivery system in model rats: formulation design, in vitro and in vivo evaluation
Published in Drug Development and Industrial Pharmacy, 2019
Qiuxuan Yang, Qilong Wang, Yingshu Feng, Qiuyu Wei, Congyong Sun, Caleb Kesse Firempong, Michael Adu-Frimpong, Ran Li, Rui Bao, Elmurat Toreniyazov, Hao Ji, Jiangnan Yu, Ximing Xu
Growing epidemiological evidence showed that the prevalence of hyperuricemia is increasing rapidly over the past decades, up to 20–25% in adult men, gradually becoming a disease with a high rate of disability [1]. Hyperuricemia, one of the most common metabolic disorders occurring in human beings, is caused by an elevated level of uric acid (UA), which result from the excessive production of uric acid, and/or decreased excretion of uric acid through the kidney [2]. More studies have shown that hyperuricemia is not just a single condition with extortionate UA levels, which is also acknowledged high-risk factor for the process of kidney and cardiovascular diseases. Kidney is a vital organ for maintaining reasonable UA level and approximately two-thirds of uric acid in the body is excreted by the kidney. Thus, urate crystallization gets deposit in the kidney if uric acid surpasses the limit amount the kidney can excrete, which could be the high risk for renal injury [3]. In this regard, lowering the UA level is the major goal in treating hyperuricemia and its complications. There are several drugs such as allopurinol that can act on the development of hyperuricemia by inhibiting the activity of xanthine oxidase (XO) to reduce the generation endogenic urate while others drugs viz. probenecid and benzbromarone could also heighten the excretion of UA. However, most of the hyperuricemic-based drugs have strongly been linked to adverse side effects such as nephritic and gastro-intestinal-toxicity [4]. Therefore, safer and more effective drugs are urgently needed to combat hyperuricemia.