Scratch assay

Although the Boyden chamber and scratch assays have provided new insights into the mechanisms of cell migration, they are unable to achieve and maintain a linear gradient of signals. The visualization of cell migration cannot be achieved with Boyden chambers either. 

Walter, M.N.M., Wright, K.T., Fuller, H.R. et al. 2010. Mesenchymal stem cell-conditioned medium accelerates skin wound healing An in vitro study of fibroblast and keratinocyte scratch assays. Exp Cell Res316(7) 1271-81. 

There was added to 250 ml of a concentrated butyl acetate extract containing 74,000 units of the acid form of penicillin per ml, 50 ml of a butyl acetate solution containing 0.238 g per ml of procaine base. The solution was agitated for one hour. The precipitate which formed was very gummy and not in the form of discrete crystals. This precipitate was crystallized by scratching the side of the vessel and agitating further. After this treatment 18.25 g of crystalline procaine penicillin was obtained which assayed 1010 units per mg representing a yield of 99.6% of the activity contained in the concentrated extract. 

Yarrow JC, Perlman ZE, Westwood NJ et al (2004) A high-throughput cell migration assay using scratch wound healing, a comparison of image-based readout methods. BMC Biotechnol 4 21... 

Secondary effects of irrigation fluids ex vivo eye irritation assay with four scratches on the cornea, incubated for 2 days and treated with artificial tears containing CaCl in 0.13 mmol/L concentration each 24 drops per day with 30 min of interval between phosphate and tear application. Second image is taken after 2 days with obvious comeal calcification. 

Qian X, Jin L, Hayden RT, et al. Diagnosis of cat scratch disease with Bartonella henselae infection in formalin-fixed paraffin-embedded tissues by two different PCR assays. Diagn Mol Pathol. 2005 14 146-151. 

Fig. 6 Wound healing assay of fibroblast cells (w/ and w/o plasma treatment), (a) images of scratch wound at 0, 12 and 22 hours APP treated (for 30 seconds) wound showed faster closure compared with untreated control, (b) the migration rate for APP treated wound and untreated control (at 12 and 22 hours after APP treatment) [23]...

Epoxy-modified Mesua ferrea L. seed oil-based polyurethane/clay nanocomposites at different loadings (1-5 wt%) have been studied as biocompatible biomaterials. The partially exfoliated nanocomposites were prepared by an ex situ solution technique under high mechanical shearing and adequate ultrasonication at room temperature. The nanocomposites exhibited enhanced mechanical properties such as tensile strength (twofold) and scratch hardness (five-fold), thermostability (to about 40°C), and an increase in the rate of biodegradation between five- and ten-fold. All the nanocomposites showed RBC haemolysis inhibition observed by anti-hemolytic assay carried out on the sterilised films. 

Domoic acid was assayed using ddY strain mice (body weight 18-20 g, male) by intraperitoneal administration. At a 40 pg dosage of authentic domoic acid, the mouse showed a typical scratching syndrome , where it repeatedly scratches its abdominal parts with its hind limbs and then moves around for 45 min after injection, but does not die. At a dose of 80 pg, mice died in 15 min. Because of its low sensitivity, the mouse bioassay was used only to check high levels of domoic acid. 

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