Pouch method

T.C. Wang, Pouch method for measuring permeability of organic vapors through plastic films, American Chemical Society, Division of Organic and Plastic Chemistry, Coat. Plast. Preprints, 31 (1975) 442- 7. 

The other is called migration tests with the pouch method. The films are cut and formed into pouches of 2 dm inner surface. The pouches are filled with 20 cm of liquid, sealed and stored at 20, 40, or 50 °C. In this case, the ratio of the volumes is a = 5. The liquid consists of 3% acetic acid in water and isooctane. The amount of the contaminant is measured in the liquid at intervals. 

Using sniff test method with container enclosed in poly/foil/poly pouch with 38 mm screw cap. 

We performed collaborative studies using the ELISA methods with model processed foods (sausage, boiled beef in an aluminum pouch, tomato sauce, biscuit, juice, and jam) containing allergen proteins. The six... 

The alternative to using a dish is to form the material into a bag and this so-called pouch or sachet method is often used for plastics films. The advantages are that a larger surface area is exposed, leaks through the wax seal are eliminated, and the conditions are more similar to packaging applications. It is less attractive for rubbers because they are not often used in that sort of packaging application and an alternative to heat sealing the pouch would be necessary. 

The pharmacologic screening must be performed by a battery of tests, which will prove its efficacy by various methods (e.g., antiinflammatory). These tests are necessary to ascertain the activity of rat paw edema, adjuvant arthritis, granuloma pouch, ascitis, and others. 

Ford et al. (1995) assessed the intestinal permeability changes induced by non-steroidal antiinflammatory drugs in the rat. A subcutaneous air pouch was formed by injection of 10 ml sterile air prior to the experiment. Five ml of a 0.4 % carrageenan solution were injected into the pouch simultaneously with a subcutaneous injection of various doses of the non-steroidal anti-inflammatory drug and the rats allowed access to food. After various time intervals, different markers were given orally and urine collected for 5 h. The use of [51Cr]-EDTA as marker was found to be the most sensitive and reproducible method. The results correlated well with data of ulcer formation. 

Herrmann KS (1983) Platelet aggregation induced in the hamster cheek pouch by a photochemical process with excited fluorescein isothiocyanate-dextran. Micovasc Res 26 238-249 Just M, Tripier D, Seiffge D (1991b) Antithrombotic effects of recombinant hirudin in different animal models. Haemostasis 21 (Suppl l) 80-87 Matsuno H, Uematsu T, Nagashima S, Nakashima M (1991) Photochemically induced thrombosis model in rat femoral artery and evaluation of effects of heparin and tissue-type plasminogen activator with use of this model. J Pharmacol Methods 25 303-317... 

Materials and articles in contact with foodstuffs - Plastics - Part 6 Test methods for overall migration into olive oil using a pouch Materials and articles in contact with foodstuffs - Plastics - Part 7 Test methods for overall migration into aqueous food simulants using a pouch... 

This fractionation method was subsequently used successfully by other investigators (Bll, D2a, Gl, G64, H39, H40, II, 12, N6, N7, P14, S6-S9, W7). Schrager (SIO) 12 years later severely criticized it and considered that measurement of mucosubstances by determination of their peptide moiety was an improper technique for measuring the gastric juice mucosubstances. He simultaneously estimated the tyrosine and hexosamine contents of the mucoprotein and mucoproteose fractions and found no quantitative correlation between the two. He therefore concluded that tyrosine measurement was not adequate for quantitation of these fractions (see Section 2.2). These results are contradicted by recent data of DeGraef (D2a) obtained on Heidenhain pouches which show very satisfactory correlation between mucoprotein and mucoproteose assay by means of tyrosine and hexosamine quantitation (see Fig. I8a). 

Individual foil packets are tested for proper sealing. Several methods of rapid seal integrity testing have been devised, such as the vacuum underwater method, detection of tracer material sealed within the pouch, purging with detectable gas, IR seal inspection, and electronic air-tightness testers. ... 

This technique is still evolving. The favored approach at present is to submerge a small, known amount of suspension inside a secured Durapore (polyvinylidene fluoride) membrane pouch (Millipore Products, Bedford, MA) of suitable porosity in teabag fashion in a suitable dissolution medium using the USP Method 1 Paddle Apparatus. Optimization of experimental conditions (rate of agitation, volume and type of medium, temperature, etc.) must be established to achieve reproducible results. 

Seismic, heat-flow and xenolith data provide constraints on different physical properties, and differences between estimates are expected. Seismic methods determine the depth to a low-velocity zone at the base of higher-velocity lithospheric lid (e.g. James Pouch 2002 Ken-... 

Its mechanism of action, however, is not completely elucidated. Kamakura et al. [94] studied the effects of stem bromelain on the plasma kallikrein system, bradykinin levels and plasma exudation at the inflammatory site in rats with a kaolin-induced inflammation of an air pouch. Bromelain caused a dose-dependent decrease of bradykinin levels (measured with the method of Minami et al. [95]) at the inflammatory site and a parallel decrease of the prekallikrein levels in sera [88]. Plasma exudation was also reduced dose-dependently. Bradykinin-degrading activity in sera was elevated after bromelain treatment, but not in the pouch fluid. The authors conclude that bromelain inhibits plasma exudation through inhibition of the bradykinin generation at the inflammatory site via depletion of the plasma kallikrein system. Bromelain also shows a dose-dependent analgesic effect in concanavalin A-injected paws of 5.6 mg/kg i.v.), considered to be due to decrease of high molecular weight kininogen [96]. 

The most common method of transplanting tumors is by subcutaneous (usually near the abdominal wall or the thigh) inoculation. Other sites of tumor implantation include muscle (usually the leg), peritoneal cavity, kidney, liver, adrenal, spleen, ovaries, uterus, and intestine. In order to observe the tumor while it is growing, several investigators have transplanted tumors in transparent windows or chambers placed on the rabbit ear, hamster cheek pouch or dorsal skin of rodents (Fig. 1). 

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