French press

Barenholz, Y., Amselem, S., and Lichtenberg, D. (1979). A new method for preparation of phospholipid vesicles (liposomes). French press, FEES Lett.. 99, 210-214. 

To check if PemB is surface exposed, E. chrysanthemi cells were subjected to proteolysis. Treatment of the cell suspension with trypsin, proteinase K or chimotrypsin at a concentration of 0.1 to 1 mg/ml for 1 h did not cause PemB proteolysis or its liberation into the medium. Cell pre-treatment with EDTA-lysozyme, which renders the periplasmic proteins accessible to proteases, gave no effect. PemB was also resistant to proteolytic digestion in extract of cells disrupted by sonication or in a French press. Only addition of Triton X-100 (up to 0.1%) causing formation of the micelles with PemB lead to a quick proteolyis of this protein (data not shown). In another approach to analyse the PemB exposition, bacterial cells were labelled with sulfo-NHS-biotin. This compound is unable to cross membranes and biotinylation... 

Finally, a recently published crossover study of coffee oil lipid extracts by Urgert et al.27 compared the effects of 60 mg/day of cafestol with a mixture of 60 mg/day of cafestol plus 50 mg/day of kahweol. These doses were comparable to consuming 10 to 20 cups of boiled Turkish or French-press coffee. In 10 healthy men, 18 days of cafestol alone resulted in significant increases in total cholesterol (0.79 mmol/L [31 mg/dL]), LDL-C (0.57 mmol/L [22 mg/dL]), and TG (0.65 mmol/L [58 mg/dL]), relative to baseline. Compared to cafestol alone, the cafestol/kahweol mixture resulted in additional increases in total cholesterol (0.23 mmol/L [9 mg/dL), LDL-C (0.23 mmol/L [9 mg/dL]), and TG (0.09 mmol/L [8... 

To reduee vesiele size and the number of bilayers, high pressure filtration via polyearbonate membranes as well as high pressure homogenization in a French press or in a mierofiuidizer are appropriate manufacturing procedures. Sonieation may also be applied, although the resulting dispersion does not have the same particle sizes. 

At ODgoo = 0.5, IPTG (0.5 mM) was added, and afterwards cells were grown overnight at a temperature of 30 °G. Gell pellets were resuspended in 50 mM Tris, pH = 7.6, 0.5 mM PLP next, 150 pg of purihed Serratia marcescens nuclease was added. Gells were lysed using a Spectronic French Press at... 

Mechanical disruption methods include sonica-tion, high-speed homogenization using a French press, and bead milling, which is especially suitable... 

CA032 De Roos, B., A. Van Tol, R. Urgent, et al. Consumption of French-press coffee raises cholesteryl ester transfer protein activity levels before LDL cholesterol in normolipidemic subjects. J Intern Med 2000 248(3) 211-216. 

Closed, spherical, single-bilayer, 300- to 600-A-diameter surfactant and/or phospholipid aggregates dispersed in aqueous solutions. Ultrasonic dispersal of multilamellar vesicles (MLVs) or employing procedures such as French Press filtration result in SUV formation. 

The French pressed expl consisting of RDX/-beeswax (or paraffin)/0.5-2.0% graphite is similar to US Composition A. It is called in French Hexogene/cire d abeille. The castable composition consisting of RDX 59-5, TNT 39.5 beeswax 1% is similar to US Composition B. It is called in French Hexolite or HT (Hexogene-Tolite)... 

Early methods of purifying alkaline phosphatase from E. coli involved heat shock (4), disruption of cells with a French press (4, 34, 35), and... 

Most results on calcium transport have been obtained using cytoplasmic membrane vesicles, which may be prepared in inside-out or right-side-out configurations. Inside-out vesicles may be obtained by the disruption of E. coli cells in a French press. These then accumulate Ca2+ in an energy-dependent fashion, provided ATP or an oxidizable substrate is available. Addition of phosphate enhances the uptake of calcium as calcium phosphate is precipitated inside the tell, thus accounting for the lack of exchangeability of the calcium.186... 

In a simple model of homogenization in a French press, the process of the disruption of the cell wall is modeled by a first-order law. Then, the amount of protein released, R, varies with the number of passes of broth through the homogenizer, N [Eq. (8.58)], where Rm3X is the maximum amount of protein obtainable through homogenization and k is a constant. 

Ball mills are best suited for breaking up strong cell walls such as those encountered in Gram-positive bacteria, but scale-up is limited beyond the small pilot scale. French presses are the apparatus of choice for large-scale homogenization of cells. 

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