Liver minced tissue

Fluoroethanol itself is innocuous towards a variety of tissue constituents, a series of enzymes in rat-liver mince, and the respiration and metabolism in liver, kidney, heart and brain slice.3 After a period of incubation in those tissues known to contain alcohol dehydrogenase, e.g. liver and kidney, the respiration and pyruvate oxidation were strongly inhibited. Likewise, following a period of incubation with yeast, acetate oxidation was blocked. These inhibitions were similar to those produced by fluoroacetate, and the facts can best be explained by the oxidation of fluoroethanol to fluoroacetic acid by alcohol dehydrogenase. 

Respiration is generally regarded as the source of energy necessary to support life. That this is true does not need verification in an advanced treatise, but one specific case may be cited. Borsook and Dubnoff (14) have found that the synthesis of hippuric acid from glycine and benzoic acid can occur only in the presence of intact liver cells. Extracts and minced tissues do not suffice, which leaves but the one conclusion, that the respiration of living tissue is the source of the energy. 

In the past, dissociation of the nucleoprotein complex has been brought about by salt solutions or by heat denaturation,129 but, more recently, decomposition has been effected by hydrolysis with trypsin,126 or by the use of dodecyl sodium sulfate130 or strontium nitrate.131 Some virus nucleoproteins are decomposed by ethyl alcohol.132 This effect may be similar to that of alcohol on the ribonucleoproteins of mammalian tissues. If minced liver is denatured with alcohol, and the dried tissue powder is extracted with 10% sodium chloride, the ribonucleoproteins are decomposed to give a soluble sodium ribonucleate while the deoxyribonucleoproteins are unaffected.133 On the other hand, extraction with 10 % sodium chloride is not satisfactory unless the proteins have first been denatured with alcohol. Denaturation also serves to inactivate enzymes of the tissues which might otherwise bring about degradation of the nucleic acid during extraction. 

For liquid matrices such as milk, a pretreatment step for fat removal that is accomplished by centrifugation (1 -3) or hexane extraction (4) may be required. Solid samples such as muscle, kidney, and liver necessitate usually more intensive sample pretreatment through use of a mincing and/or a homogenizing apparatus. In some cases, as in the analysis of apramycin in swine kidney tissue, protein digestion with concentrated ammonium hydroxide may be needed to achieve better recovery of the analyte from the matrix (5). 

For analyzing amphenicol residues in liquid samples such as milk, a pretreatment centrifugation step for fat removal is usually required (21, 22). Dilution of milk samples with water prior to solid-phase extraction cleanup is also often needed (23, 24). Semisolid samples such as muscle, kidney and liver, require, however, more intensive sample pretreatment. The most popular approach for tissue break-up is through use of a mincing and/or a homogenizing apparatus. 

Prior to analysis of -lactam residues in liquid foods such as milk, a pretreatment step for fat removal, accomplished by centrifugation (69-71), is usually required. In instances where milk is to be submitted to ultrafiltration, dilution with water/acetonitrile (72-76) or water/acetonitrile/methanol (77-79) is often needed. Milk filtration (80) or dilution with acetate (81, 82) or phosphate buffers (83) is sometimes essential prior to solid-phase extraction. Unlike milk, semisolid food samples such as muscle, kidney, and liver require normally more intensive sample pretreatment. Tissue break-up is mostly carried out by the combined use of a mincing apparatus and a tissue homogenizer. 

Before the extraction procedure may commence, the sample must be prepared in such a way that it is in a condition for extraction of the analyte(s). For analyzing sulfonamide residues in liquid samples such as milk, a pretreatment dilution step with water prior to direct fluorometric detection may be required (207). Dilution of milk with aqueous buffer (208) or sodium chloride solution (209) prior to sample cleanup has also been reported. For the analysis of honey a simple dissolution of the sample in water (210, 211) or aqueous buffer (212) is generally required. Semisolid samples such as muscle, kidney, and liver, require, however, more intensive sample pretreatment. The analyte(s) must be exposed to extracting solvents to ensure maximum extraction. The most popular approach for tissue break-up is through use of a mincing and/or homogenizing apparatus. Lyophilization (freeze-drying) of swine kidney has been carried out prior to supercritical-fluid extraction of trimethoprim residues (213). 

Preparation of Microsomal and Cytosolic Fractions. At the end of the 5 week period on experimental diets, all animals were killed via sodium pentobarbital anesthesia (120mg/kg body weight). The tissues were perfused in situ with ice-cold normal saline via the right ventricle of the heart, excised, trimmed free of connective tissue, minced, and washed thoroughly with ice-cold deionized water. The subcellular fractions of liver, lungs, kidneys, etc., were prepared as previously described (26). 

Beef liver (or lung) was minced and then autolyzed for twenty-four hours before extraction with an alkaline solution saturated with ammonium sulfate. Protein was precipitated by warming the extract, and the heparin-protein complex was precipitated from the supernatant liquor on acidification. Extraction of the complex with ethanol removed fatty material, and tryptic digestion removed most of the protein. The heparin was precipitated with ethanol, redissolved in warm alkaline solution to destroy trypsin, and reprecipitated with acetone. This material, crude heparin, was isolated in a yield of 15-50 g. per 100 lb. of animal tissue. In a later paper," the purification of crude heparin by fractionation successively with Lloyd s reagent, cadmium chloride, and acetone, was described. The purified heparin w-as 100 times as active as the crude material. Scott and Charles" reported the presence of nitrogen... 

Each animal was sacrificed by captive bolt after the appropriate withdrawal interval (4, 6, 14 and 28 days after the 2nd dose) and processed as in an abattoir. The entire liver, kidneys and udder were excised and 1-2 kg samples of muscle from both the flank and the udder diaphragm and 1-2 kg samples of fat from the abdominal area were collected. Each organ and tissue was minced and processed three times through a commercial meat grinder to prepare respective homogenate samples. Sub-samples (200-300 mg) were prepared in triplicate for total residue analysis. Total radioactivity concentrations, expressed as pirlimycin free base equivalents, were determined by direct liquid scintillation counting (liquids) or combustion analysis (solids) following standard techniques. 

Sample preparation Mince 0.1-0.3 g tissue with a scalpel and incubate at 37° with 0.5 mL water for 1 h. Add MeCN 85% phosphoric acid water 20 2 78 (muscle, renal medulla, lung) or MeOH MeCN 85% phosphoric acid water 30 10 2 58 (renal cortex, liver) to a total volume of 1 mL, sonicate 30 min, filter (10 000 or 30 000 Da cutoff) by centrifuging at 2200 g for 30 min, inject 10-30 xL aliquot of filtrate. 

Guinea pig liver should be fractionated essentially as described above for rat liver. With the aid of sharp scissors, mince the tissue, fragmenting it into irregular... 

Mincing and/or homogenization of muscle, kidney, and liver samples is usually required before some type of extraction is applied. Drying of tissue samples with anhydrous sodium sulfate prior to extraction is another procedure often employed to enhance the recovery of the analytes.Sample extraction and precipitation of concurrent proteins can be accomplished with a great variety of organic solvents including ethyl acetate, acetone, methanol, acetonitrile," " ethanol, ethylenediamine-tetraacetic acid (EDTA)-Mcllvaine buffer solution," EDTA and methanol/water," and trichloroacetic acid and acetonitrile."" ... 

The nutritional requirements of the parasitic amoebae, most frequently Endamoeha histolytica have been of interest to a great many investigators ever since Boeck and Drbohlav first cultured the dysentery amoeba. Aside from E. invadens, a reptilian parasite, and in spite of enormous effort, no parasitic form has been successfully cultured in vitro in the absence of other living organisms. Even for E. invadens fresh snake tissue or minced chick embryo or fresh liver slices must be added. We know, however, that E. histolytica multiplies abundantly in sterile abcesses, so it seems... 

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