Rodent Hairs Research Articles

Extraction of Light Filth from Raw and Processed Wheat Germ

Abstract A method developed for the extraction of light filth from raw and processed wheat germ utilizes chloroform defatting and acid hydrolysis followed by wet sieving. Light filth is extracted with mineral oil from a hot ethanol or isopropanol solution. The collaborative study resulted in 90, 89, and 84% average recoveries of spike insect fragments, rodent hairs, and adult insects, respectively. The method is recommended for adoption as official first action.

Comparison of White Gasoline and n-Heptane for Recovery of Insect Fragments and Rodent Hairs from Food Products

Abstract A study is described in which re-heptane is compared with gasoline as flotation oils from water and alcohol lower phases. n-heptane, containing less than 4% toluene, gave higher and more reproducible insect fragment and rodent hair recoveries than gasoline when used with an alcohol lower phase. Recoveries were comparable between n-heptane and gasoline when used with a water lower phase. In both cases filter papers were cleaner or contained equal amounts of plant debris as obtained with gasoline. It is recommended that re-heptane replace gasoline for use as the flotation oil in alcohol and water extractions, and that "n-heptane# replace the word "gasoline# in method 36.002(o).

Method for the Extraction of Light Filth from Plant Gums

Abstract A new method has been developed for the extraction of extraneous materials from plant gums. Hydrochloric acid and autoclaving are used to break down and disperse partially insoluble gums, followed by sieving and extracting using a trap flask. Collaborative studies gave reproducible recoveries of rodent hairs and insect fragments, and the method is recommended for adoption as official first action.

Staining Technique to Differentiate Insect Fragments, Bird Feathers, and Rodent Hairs from Plant Tissue

Abstract A staining method is described in which plant material is differentially stained from insect fragments, rodent hairs, and bird feather barbules. Because the colors of the stained plant tissue contrast with that of the dyed extraneous material, counting of the contaminants becomes easier, rapid, and more accurate.

Rapid Method for the Extraction of Light Filth from Paprika

Abstract A rapid extraction method has been developed for the separation of light filth from paprika; in the method, paprika is defatted with a surfactant, wet sieved, and floated with n-heptane from 60 % alcohol and Tween 80-Versene mixture. Collaborative results by the method gave 8.7 and 16.1% increased recovery of insect fragments and rodent hairs, respectively. The method is recommended for adoption as official, first action.

Radiation Injury and Recovery in Anagen and Telogen Rodent Hairs

Reduced incorporation of isotope-labeled compounds was studied to assess postirradiation damage and recovery in growing (anagen) and resting (telogen) rodent hairs. Reduced uptake of ${}^{3}{\rm H}...

Contamination Indexes in Degerminated Corn Products

Abstract Insect and rodent contamination in corn milling was studied to improve current methodology and recommend new methodology. Representative whole corn processing equipment, degerminators, grading equipment, and finished products were sampled. Whole corn samples were examined visually and by X-ray techniques; all samples were examined by heavy and light filth extraction methods similar to AOAC procedures. Whenever possible, contaminant counts throughout the system were weighted for stream flow before analyzing and presenting data. WRAP (Weighted Regression Analysis Program) was used in data analysis. The least number of equivalent whole exoskeletons gave the best correlations with radiograph data (r2 values ranging from 57.1 to 69.1%) of any of three methods used to report insects of kernel interior origin recovered in cracking-flotation of whole corn samples. The second trapping in light filth extractions was valuable in recovering additional rodent hairs, insects, and insect fragments from all types of corn and mill samples.

Evaluation of the Effects of Eleven Bleaching Agents on Ground Cocoa Bean Tissue, Insect Fragments, and Rodent Hairs

Abstract Eleven bleaching agents were used to decolorize cocoa tissues, and their effects on insect fragments and rodent hairs were studied. Gilorine bleaches, potassium permanganate, and hydrogen peroxide all result in good bleaching of ground cocoa. However, chlorine bleaches completely destroy rodent hair, and potassium permanganate is not effective for high fat products. Hydrogen peroxide decolorizes cocoa bean tissue very well and does not destroy rodent hairs nor decolorize insect fragments. A mechanical means of evaluating the amount of bleaching of cocoa bean tissues is also described. Future studies are planned on the use of hydrogen peroxide as a plant tissue bleaching agent

Rapid Method for Separation of Extraneous Materials from Whole and Degerminated Corn Meal, Prepared Mustard, and Soy Flour

Abstract A rapid method, based on acid hydrolysis in the presence of mineral oil, has been developed to separate extraneous materials from whole and degerminated corn meal, prepared mustard, and soy flour. Corn meal may be first examined for rodent excreta by method 36.032 and then examined for light filth, or it may be analyzed directly for light filth by the acid hydrolysis method. Soy flour is prepared for analysis by solubilizing the protein in dilute sodium chloride solution in the presence of mineral oil. The Kilborn separatory funnel is used with all 3 products. The proposed method improves recoveries of insect fragments by 13—34% and rodent hair recoveries hy 25—54%. Analyst time required for actual assay is reduced by at least onethird. The method will be subjected to collaborative study

MEASUREMENT OF THE RATE OF GROWTH OF RODENT HAIR USING CYSTINE LABELLED WITH SULPHUR-35.

THE use of radioactive markers for the measurement of rates of wool growth has been described by Downes and Lyne1,2. Cystine, labelled with sulphur-35, was injected at intervals of not less than three days, and autoradiographs of the wool were prepared using a stripping film technique. Distances between the regions of incorporation of amino-acid into the wool were measured in order to obtain estimates of rates of wool growth.

Filth in Fruit Paste

Abstract Development of a method for recovering all types of filth encountered in fruit paste has been initiated. A number of people were consulted about their experiences in examinations of fig paste by method 36.053 and their efforts to improve recovery of rodent hairs, fly eggs, and maggots by supplementary or substitute procedures. Their answers indicate that a method incorporating extensive digestion of the fruit tissue to liberate filth elements, followed by sieving on a No. 140 screen and washing forcibly with a spray of water to reduce the amount of fruit tissue, then examining the sieve residue microscopically for insects and hairs, appears feasible. Application of this procedure to a commercial straight Calimyrna fig paste resulted in improved filth recovery compared to the AOAC method but proved time-consuming due to the amount of residual fig tissue on the sieve. Kerosene-water flotation treatment of the washed residue on the screen expedited the counting of filth elements, giving recoveries intermediate to those obtained by the AOAC method and direct microscopic examination of digested and sieved residues. It is recommended that the study be continued.

Modification of the Radiation Effect on Hair Roots of the Mouse by Actinomycin

A technique is described for the microscopic examination of rodent hairs. Actinomycin D was shown to exert a synergistic effect on dysplastic changes of growing hairs induced by local x irradiation. (C.H.)

Modification of radiation responses of tissue by colchicine. Effects on mouse hair roots.

Several recent reviews have described the effects of various chemical and physical agents in modifying radiation responses in normal tissues and tumors (1–3) . The observation that irradiation induces profound morphologic changes in animal and human hairs (4, 5) has provided a useful experimental device for the screening of such agents in rodents (6). At any given time areas of skin in rats and mice can be found in which most of the hair follicles are in the resting phase of the hair cycle. These telogen hair follicles are mitotically inactive and are insensitive to radiation (4). If the resting hair is disturbed by plucking, its follicle becomes active and a growing (anagen) hair is formed which is highly radiosensitive. When anagen hairs are irradiated, dysplastic changes in the shafts and atrophy of the bulbs occur, the number of hairs affected being proportionate to the dose of radiation sustained. Recent experiments in rats and mice have shown that anagen hairs also undergo profound atrophic and dysplastic changes following intraperitoneal administration of large doses of colchicine (7). Since these microscopic changes strongly resemble alterations in human hair induced by x-ray irradiation (5), the rodent hair indicator system was utilized to determine the possible synergistic role played by colchicine in increasing these x-ray effects. Our chief interest centered on the application of positive findings to the therapeutic implications of altering the radiosensitivity of certain forms of malignant growth by prior administration of colchicine. Methods The studies were carried out on adult female mice of the Carworth Farms No.1 strain. In these animals the hair cycle lasts for seventeen to twenty days from earliest anagen to the onset of telogen. Hairs were completely plucked from both haunches of all animals at the start of each experiment, one haunch being used for examination of the effects of colchicine and irradiation, and the other for examination of colchicine effects alone (Fig. 1). Occasional mice showing areas of newly growing hairs which were not easily removed were discarded from the study. The mice received x-ray irradiation on the tenth day after initial plucking, and four days later the newly growing hairs in the control and treatment areas were plucked. These hairs were then floated on a shallow layer of water covering the bottom of a 5.5 × 1.5 cm. glass Petri dish which had been scored in grid pattern on its underside. The hairs were examined with a binocular dissecting microscope at 45 × magnification with transmitted blue light. For each animal the following stages of hair growth were recorded and counted for the “differential hair count”: normal anagen, dysplastic, catagen (hairs transitional between anagen and telogen), and telogen (Fig. 2).

Tests on the Efficiency of Various Filth Recovery Procedures: II. Insect Fragments and Rodent Hairs from Flour

Tests on the Efficiency of Various Filth Recovery Procedures: II. Insect Fragments and Rodent Hairs from Flour

Monitoring the extraneous matters in pulps of tomato, guava, mango and strawberry marketed during the seasons of the year

Fruit-derived products sold in Brazil and for exportation are required to comply with the quality and safety standards. These products and, among them, the fruit pulps may contain extraneous materials due to the inappropriate conditions or practices during their production, storage and distribution, including filth, decomposed material and miscellaneous materials. This study aimed at evaluating the sanitary conditions (regarding to extraneous materials) of fruit pulps sold in the Great Sao Paulo, during the four seasons of 2010. This investigation analyzed 115 tomato pulp, 93 guava pulp, 99 strawberry pulp and 89 mango pulp by means of the techniques described in the AOAC, 18th, 2005, Chapter 16 - Extraneous Materials: Isolation. Insect fragments were the most frequent filth category detected in the pulps (in 93 % of guava and strawberry, 77 % of tomato and 48 % of mango samples), followed by the rodent hair (in 24 % of tomato, in 3 % of guava, in 1 % of strawberry and in 0.5 % of mango samples). The occurrence of mites was mostly frequent in strawberry samples (33 %). This study indicated that the majority of the analyzed pulps showed satisfactory sanitary conditions, evidencing that the Good Manufacturing Practices was adopted by the productive sector.