ABSTRACT
Central composite design (CCD) is one of the most commonly used design methods in response surface optimization and has been widely applied in the field of pharmaceutics to optimize preparations. On the 20th anniversary of the introduction of CCD into China, the paper reviews its application in domestic pharmaceutical researches. Based on the brief introduction of basic principle and operation steps of CCD, the mistakes emerging in the application of CCD are summarized, including conceptual confusion with Box-Behnken design and face-centered CCD as well as wrong designs. Besides, the issues concerning the selection of factors and responses are discussed. The article is helpful for researchers to comprehensively understand the CCD and facilitates the rational application of this method.
ABSTRACT
Natural deep eutectic solvent (NDES) is a kind of deep eutectic solvents (DESs) which is composed of natural substances with good biocompatibility. Those substances can function as hydrogen bond donor and acceptor, such as choline, amino acids, sugars, etc. NDES have been widely used in many fields due to their advantages of low cost, easy preparation and environmental friendliness. It is especially suitable for the pharmaceutical industry because of its good biocompatibility and safety for use. In this paper, we firstly review the molecular simulation methods for current design of DESs from the formation principle. And then, the materials and preparation of NDES are reviewed and the physicochemical properties are further described. Finally, we review the current application of NDES in pharmaceutics including increasing drug solubility, promoting drug permeability and enhancing oral drug absorption, and meanwhile their future applications in pharmaceutics were also prospected.
ABSTRACT
The in vivo fate is a crucial factor that governs the successful translation of nanoformulations. However, one of the current biggest challenges is with the real-time monitoring of the body of the nanoparticles themselves. Conventional radioactive or fluorescent probes give signals even after they are disassociated from the particle matrix, generating interference to bioimaging and leading to misjudgment of results. Environment-responsive fluorescent dyes are regarded as promising tools due to signal switching in response to the changes in the environment. Currently, there are three categories of dyes in bioimaging of nanoparticles based on Förster resonance energy transfer (FRET), aggregation-induced emission (AIE) and aggregation-caused quenching (ACQ). They have similar characteristics that strong fluorescence is emitted when they are embedded in the matrix of nanocarriers, whereas the fluorescence quenches upon release from the matrix due to dissociation of nanocarriers. The fluorescence switching reflects the existing status of the nanocarriers and therefore helps to interpret the in vivo behaviors. FRET and AIE probes have been widely used in elucidating the interactions between nanoparticles and cell models. However, they show intrinsic defects in studying in vivo fate of nanoparticles. ACQ-based dyes are sensitive to water, a universal factor in the biological environment. Therefore, with the help of bioimaging equipment, the in vivo trafficking process of nanoparticles can be unraveled. This review article tends to provide an overview on the rationale, pros and cons and applications of the three categories of environment-responsive fluorescent dyes in the investigation of the in vivo fate of nanocarriers.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the anatomy of the medial pedis composite flaps with saphenous nerve and tendon and its application in the repair of tendo calcaneus and adjacent defects.</p><p><b>METHODS</b>10 cadavers (20 sides) were observed. The origin, course, size and the distribution of the medial plantar artery were studied. 12 cases with tendo calcaneus and adjacent defects were reconstructed with the medial pedis composite flaps with saphenous nerve. Donor site defects were covered with free skin graft.</p><p><b>RESULTS</b>The medial plantar artery gives off deep branch [diameter (1.5 +/- 0.3) mm] and superficial branch [diameter (1.0 +/- 0.2) mm]. In 18 sides, the deep branches give off the medial branches and lateral branches. While in 2 sides, the superficial branches give off the medial branches and lateral branches with no big branches from the deep branches. There are branches of saphenous nerve and medial dorsal cutaneous nerve in the flap. All the flaps were survived. 8 cases were followed up for one months to one years. Good color, texture and function of the flaps were achieved.</p><p><b>CONCLUSIONS</b>The medial pedis composite flaps with saphenous nerve can repair tendo calcaneus and adjacent defects. It is a easy and safe procedure with reliable anatomy and good results.</p>
Subject(s)
Adolescent , Adult , Child , Female , Humans , Male , Young Adult , Foot , General Surgery , Peripheral Nerves , Surgical FlapsABSTRACT
<p><b>OBJECTIVE</b>To report an anatomical basis for the posterior tibial artery intermuscular septum branches island flaps and its clinical value.</p><p><b>METHODS</b>The origin,course, number, caliber and distribution of the posterior tibial artery intermuscular septum branches were studied in 10 adult cadavers(20 legs). 10 cases of homonymy and opposite side ankle and adjacent soft tissue defects with posterior tibial artery intermuscular septum branches island flaps, aged 20-50 years. Free skin transplantation on the donor sites.</p><p><b>RESULTS</b>The posterior tibial artery gives off 2-7 intermuscular septum branches. Its external diameter was about 0.4-1.8 mm,and the length was about 0.3-4.5 cm. The area of flaps was 7 cm x 6 cm - 20 cm x 8 cm in the group. All the flaps were survived except 1 with partial necrosis in the distant part(3 cm x 1 cm) of the flap. 7 cases were followed up two months to three years. The color, texture and appearance of the flaps were good.</p><p><b>CONCLUSIONS</b>The kind of flap has reliable blood supply, the scope of repairing was wide; avoidance of sacrificing the major artery; the flap was easy to be dissected. It was one of the ideal flaps to repair the ankle and adjacent soft tissue defects.</p>