Digestive fluids

Its relatively low toxicity is probably the result of very low aqueous solubility (0.002 g/L) and lack of reactivity with acidic (HCl) digestive fluids. 

Muscles (heart, etc.) Stomach/intestine Liver Kidney (bowel) Reproductive organs Glands Brain (Chapter 9) Sense organs Digestion, fluid circulation, motion, mechanical work Major zones of digestion Major zone of synthesis Major external rejection ion/water balance Reproduction Chemical controls Electrical control Environmental detectors... 

In the sulfite pulp process, the digestion fluid is typically made by dissolving sulfur dioxide in water in the presence of limestone until the solution contains 7.0% by weight S02, three-quarters of which is in the form of bisulfite ion. Why is this done In support of your answer to this question, calculate the pH of (a) the digestion solution prepared as above, (b) a hypothetical 7% solution of S02 alone, and (c) an actual saturated solution of S02 alone (2.9% S02), if the first acid dissociation constant of sulfurous acid is 1.7 x 10-2, at ambient temperature and pressure. 

Chlorine (Cl-) Transportation of molecules across cell membrane, digestive fluid, nerve function Muscle cramps, reduced appetite... 

Essential element in most proteins important in tertiary structure (through S—S finks) of protests involved in vitamins, fat metabolism, and detoxification pro-, cesses/ HjSQ, in digestive fluid in ascidians ("sea squirts -) replaces H,0 in photosynthesis of some bacteria HjS and Ss... 

Minerals released during digestion dissolve in the digestive fluids and are then absorbed either by specific absorption systems or by passive diffusion. 

Elam P, Vail PV, Schreiber F (1990), Infectivity of Autographa californica nuclear polyhedrosis virus extracted with digestive fluids of Heliothis zea, Estigmene acrea, and carbonate solutions,]. Invertebr. Pathol. 55 278-283. 

Shao et al. recommended the use of a simultaneous fluorimetric method for the determination of the dissolution rate of dipyridamole and aspirin tablets [34]. The powdered tablets (equivalent to weight of one tablet) of dipyridamole and aspirin were dissolved in simulated digestive fluids at 37°C, cooled, and diluted to 1 L with simulated digestive juice. The solution was filtered, and a 1 mL portion of the filtrate was mixed with 0.1 M sodium hydroxide and then set aside at room temperature for 1 h. The solution was mixed with 8 mL of phosphoric acid buffer (pH 6.8) and fluorimetrically detected for dipyridamole at 493 nm (excitation at 418 nm). The coefficients of variation for within-day and within 5 days were 2% for both dipyridamole and aspirin. 

Oomen AG, Sips A, Groten JP, Sijm D, Tolls J. 2000. Mobilization of PCBs and lindane from soil during in vitro digestion and their distribution among bile salt micelles and proteins of human digestive fluid and the soil. Environ Sci Technol 34 297-303. 

Because of rich buccal vascularity, drugs delivered by the buccal route gain direct access to the systemic circulation and are not subject to first-pass metabolism. Also, therapeutic agents do not come in contact with the acidic digestive fluids secreted by the gastrointestinal tract. 

Weston, D.P. and Mayer, L.M. (1998a) In vitro digestive fluid extraction as a measure of the bioavailability of sediment-associated polycyclic aromatic hydrocarbons sources of variation and implications for partitioning models. Environ. Toxicol. Chem., 17, 820-829. 

Landry, F. Bazile, D. Spenlehauer, G. Veillard, M. Kreuter, J. Release of the fluorescent marker prodan from poly(D,L-lactic acid) nanoparticles coated with albumin or polyvinyl alcohol in model digestive fluids (USP XXII). J. Control. Release 1997, 44, 227-236. 

Figure 2 The structure of the absorptive cell of the intestinal lining reflects its specialized function in digestion. The absorptive cell is one of the two main cell types that constitute the epithelium of the villus. The other type is the goblet cell, which secretes mucus. Cells of both types are produced by cell division in the crypts and assume their mature structure during a 2-day migration to the villus tip. Exposed in transit to the action of digestive fluids, some of the membrane covering the absorptive cell may be sloughed off. The cell is abundantly supplied with mitochondria, which provide energy for metabolic...

Weston, D.P. and L.M. Mayer. 1998b. Comparison of in vitro digestive fluid extraction and traditional in vivo approaches as measures of polycyclic aromatic hydrocarbon bio availability from sediments. Environ. Toxicol. Chem. 17 830- 840. 

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