Rabbit Skin Test for Estimation of T-2 Toxin and Other Skin-Irritating Toxins in Contaminated Corn

1974 ◽  
Vol 57 (5) ◽  
pp. 1121-1127 ◽  
Author(s):  
Choong W Chung ◽  
Mary W Trucksess ◽  
Albert L Giles ◽  
Leonard Friedman

Abstract A rabbit bioassay test has been developed which can be used for screening large numbers of field samples of corn for T-2 and other toxins. Two μl each of the control solutions, 0.005–0.12 μg standards, and about 12 samples in ethyl acetate were applied simultaneously to the closely clipped skin of a 2–3 kg young rabbit. The skin reactions were read at 24, 48, and 72 hr. The prominent features of the reactions were erythema, edema, and necrosis. The T-2 toxin equivalences of the samples were estimated by the degree of the skin reactions caused by the standards. The method is reliable to at least 0.01 μg/test or 50 ppb. Graded response to the toxin is dependent upon the use of sensitive animals and properly diluted samples and standards. Rabbits were more sensitive than weanling rats or young guinea pigs, and the method showed better reproducibility with rabbits. Citrinin and zearalenone (F-2) showed negative skin reactions when applied at a level of 20 μg/skin site. They also showed poor skin reactions when administered by intradermal injection into rabbit skin. However, all 3 mycotoxins showed distinct skin reactions in guinea pigs by the intradermal route. The test was as sensitive as the topical test using rabbits with T-2 toxin. The prominent feature of the skin reaction was induration.

1957 ◽  
Vol 105 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Jonathan W. Uhr ◽  
A. M. Pappenheimer ◽  
M. Yoneda

Guinea pigs infected by intradermal injection of living toxigenic diphtheria bacilli and protected by horse antitoxic globulin, given either before or after infection, develop delayed hypersensitivity of the tuberculin type to diphtherial proteins. The highest degree of hypersensitivity is specifically directed against diphtheria toxin (or toxoid) itself, although smaller delayed skin reactions may be evoked in sensitized animals by other diphtherial proteins common to both toxigenic and non-toxigenic strains. Animals sensitized to diphtheria toxin by infection with a toxigenic strain in this way react positively to the Schick test and their serum usually contains no detectable antitoxin 2 to 3 weeks after the initial infection. Animals infected with living non-toxigenic diphtheria bacilli become sensitized to proteins common to both toxigenic and non-toxigenic strains but do not show sensitivity to toxin. The observations suggest that a minute amount of toxoid, or of toxin comparable to that which might be liberated during infection, might induce the hypersensitive state if injected in the form of a complex with excess antitoxin. This prediction is verified by the results reported in the following paper (23).


1969 ◽  
Vol 129 (4) ◽  
pp. 623-645 ◽  
Author(s):  
Felix T. Rapaport ◽  
A. S. Markowitz ◽  
Robert T. McCluskey

Immunization of rabbits with Group A Type 12 streptococcal cell membranes has elicited serum antibodies which have the ability to cause rapid rejection of skin allografts in guinea pigs. Intradermal injection of such antisera has resulted in skin reactions characterized by prominent polymorphonuclear leukocyte infiltrates, similar to those noted in the Arthus reaction. The combined use of membrane antisera and epinephrine has resulted in hemorrhagic necrosis of the skin of guinea pigs. The ability of membrane antisera to exert these effects appears to be dependent upon the presence in the host tissues of antigen(s) shared by or cross-reacting with streptococcal membrane antigens. Such cross-reacting antigens may have a group distribution in the outbred guinea pig population. The results highlight the potential biological importance of antigens present in the Group A streptococcal membrane in the induction of altered tissue reactivity in the mammalian host.


1935 ◽  
Vol 62 (1) ◽  
pp. 39-64 ◽  
Author(s):  
R. M. Thomas ◽  
F. Duran-Reynals

1. The skin lesions in rabbits and guinea pigs following intradermal injection of tubercle bacilli (5 strains) were greatly increased in size and severity when testicle extract was added to the inoculum. Such enhancement was followed by a more widespread and rapidly progressing disease only when virulent strains were employed. 2. Attempts to suppress the development of skin lesions resulting from the injection of either normal or tuberculous rabbits with very small quantities of tubercle bacilli mixed with testicle extract were unsuccessful. 3. The skin reactions of tuberculous guinea pigs to tuberculo-protein MA 100 were greatly increased in size and markedly reduced in intensity by the addition of testicle extract to the protein solution. The toxic effect of larger quantities of tuberculo-protein was not altered by the addition of testicle extract. 4. The dispersion of tubercle bacilli through the skin of tuberculous rabbits resulted in a marked enhancement of the Koch phenomenon but was not followed by any extension of the new infection to the viscera. Tuberculous rabbits infected on two occasions with dead tubercle bacilli suspended in testicle extract showed an increased resistance to the disease when compared with controls receiving dead bacilli suspended in saline solution. 5. The resistance conferred upon tuberculous guinea pigs by superinfection was greatly increased when the bacilli employed were dispersed through the skin with testicle extract. 6. The parenteral administration of large quantities of testicle extract to recently infected guinea pigs did not result in any increase in the extent of the visceral lesions. 7. The partial immunity conferred upon guinea pigs and rabbits by vaccination with heat-killed tubercle bacilli was increased as a result of dispersion of the vaccine through the skin with testicle extract.


Author(s):  
T. V. Zvyagintseva ◽  
S. I. Myronchenko ◽  
N. I. Kytsyuk ◽  
O. V. Naumova

Considering the particular danger of remote skin reactions to ultraviolet irradiation (UVI), it is advisable to use ointments with antioxidant activity to reduce its negative effect on the skin. The rationale for the choice of ointments with antioxidant activity was the fact that they reduce the damaging effect of ultraviolet radiation in the erythemal and early post-erythemal period. The presence of a regular connection between the development of the early and late periods has given reason to assume the protective effect of ointments on the remote skin reactions. Objective: to study the effect of thiotriazoline ointment and thiotriazoline ointment with silver nanoparticles on the state of the morphological structures of the skin of guinea pigs after local UVI. Material and methods of research. The study involved 132 albino guinea pigs weighing 400-500 g, divided into 4 groups: 1 - intact, 2 - control (guinea pigs subjected to local UVI), 3 and 4 main ones. The third main group included guinea pigs that after UVI were administered thiotriazoline ointment in the treatment and prophylactic regime, the fourth main group included guinea pigs that after UVI were administered thiotriazoline ointment with silver nanoparticles in the same mode as Group 3. Ointments were applied 1 hour before irradiation and daily until erythema disappeared. Ultraviolet erythema was caused by irradiation in 1 minimum erythemal dose. After 2, 4 hours, on the 3rd, 8th, 15th, 21st, 28th day, the fragments of irradiated skin were investigated using histochemical and morphometric methods (fibroblast density and epidermis thickness). Results. Morphological changes in the skin after applying ointments with antioxidant activity were unidirectional. It was revealed that in the early periods after irradiation, thiotrazoline ointment and thiotrazoline ointment with silver nanoparticles do not affect changes in the thickness of the epidermis, but statistically significantly reduce the density of fibroblasts in the dermis on the 3rd day of the experiment compared to the control group. In the later periods, under the influence of thiotriazoline ointment, a gradual decrease in the thickness of the epidermis, which reached the norm by the end of the experiment, was observed. On the 8th day, the maximum density of fibroblasts was recorded, in the subsequent periods of the experiment, the index gradually decreased, which was accompanied by collagenization of the papillary layer in the loci of damage to collagen and elastic fibers detected in 50% of cases. In later times, under the influence of thiotriazoline ointment with silver nanoparticles, the processes of restoring the morphological structures of the skin occurred faster. In parallel with the decrease in the density of fibroblasts in the loci of the previous damage to the collagen and elastic fibers of the papillary layer, thickening of collagen fibers was observed, replacing them with segments of destruction of elastic fibers. In this group, at the end of the experiment, the collagenization locus was small, single, occurring in 16.7% of cases. Conclusions Ointments with antioxidant activity exert a positive effect on the state of morphological structures of the skin, damaged as a result of local UVI, in erythemal and post-erythemic periods. In the early periods after the local UVI, there was a general tendency for the effect of both ointments, as they reduced the density of fibroblasts on the 3rd day, but did not result in complete normalization. In the late period after local UVI , under the influence of thiotriazoline ointment and thiotriazoline ointment with silver nanoparticles, thickness of the epidermis (by 21st and 15th day, respectively) and density of fibroblasts (by the 28th day) decreased to normal while without treatment both indicators exceeded the norm by several times for 28 days of the experiment.


1996 ◽  
Vol 5 (5) ◽  
pp. 346-357 ◽  
Author(s):  
N. Van Osselaer ◽  
M. Rampart ◽  
A. G. Herman

The selectin-mediated rolling of leukocytes along the endothelial cells is a prerequisite step followed by firm adhesion and extravasation into the inflamed tissue. This initial contact can be suppressed by sulphated polysaccharides. We have studied the effect of sulphated polysaccharides on the ultimate polymorphonuclear leukocyte (PMN) recruitment and plasma leakage in rabbit skin in response to intradermal injection of various inflammatory mediators. PMN infiltration evoked by various PMN chemoattractants (FMLP, C5a desArg, LTB4and IL-8) was significantly inhibited after intravenous injection of dextran sulphate (25 mg/kg), heparin (2 × 90 mg/kg) or fucoidan (1 mg/kg). PMN-dependent plasma leakage was equally well reduced by the different sulphated polymers. Vascular permeability induced by histamine or thrombin acting via a PMN-independent mechanism was not reduced. Fucoidan was the only polysaccharide able to suppress IL-1-induced PMN infiltration for 60–70%. Local administration of dextran sulphate had no effect on PMN-dependent plasma leakage. Differential inhibition of PMN recruitment was determined after injection of dextran sulphate or fucoidan depending on the type of insult. Therefore, these results suggest that different adhesion pathways are utilized during PMN recruitmentin vivoin response to chemoattractants and IL-1.


1916 ◽  
Vol 23 (4) ◽  
pp. 475-489 ◽  
Author(s):  
Leo F. Rettger ◽  
Thomas G. Hull ◽  
William S. Sturges

The problem of eradicating ovarian infection in the domestic fowl assumes still greater importance than heretofore, in the light of data recently acquired. Not only is it of great significance to eliminate the permanent carriers of Bacterium pullorum from all flocks of fowls from the standpoint of successful poultry breeding, but also because they constitute a possible source of danger to man. Eggs which harbor Bacterium pullorum in the yolk in large numbers may produce abnormal conditions, when fed, not only in young chicks, but in adult fowls, young rabbits, guinea pigs, and kittens. The toxicity for young rabbits is most pronounced, the infection usually resulting in the death of the animals. In kittens the most prominent symptoms are those of severe food-poisoning with members of the paratyphoid group of bacteria. The possibility of infected eggs causing serious disturbances in young children and in the sick and convalescent of all ages must therefore receive serious consideration. Ovarian infection of fowls is very common throughout this country. Hence, a large proportion of the marketed eggs are infected with Bacterium pullorum. When such eggs are allowed to remain in nests under broody hens, or in warm storage places, for comparatively few hours, they contain large numbers of the organism. Soft boiling, coddling, and frying on one side only do not necessarily render the yolks free from viable bacteria; therefore, eggs which have gone through these processes may, like raw eggs, be the cause of serious disturbances in persons who are particularly susceptible to such influences, and especially to infants. That no well authenticated instances of egg-poisoning of this kind are on record does not warrant the assumption that there have been no cases. The etiology of infantile stomach and intestinal disturbances is as yet too little understood; in fact, it may be said that many of these disorders have no known cause, and almost as much may be said regarding gastro-intestinal diseases in later life. Furthermore, since the ailments caused by infected eggs would not make themselves felt presumably until several days after their ingestion, little or no suspicion would fall upon the eggs. It may be said, too, that the wide distribution of ovarian infection in the domestic fowl has come about only in the last few years, hence its possible danger to man is one of recent development.


1951 ◽  
Vol 112 (3-4) ◽  
pp. 446-449
Author(s):  
L. B. Winter

1919 ◽  
Vol 29 (2) ◽  
pp. 199-213 ◽  
Author(s):  
Yutaka Ido ◽  
Hiroshi Ito ◽  
Hidetsune Wani

1. Spirochata hebdomadis is always present in seven day fever and can be confirmed by animal experiments with guinea pigs of light weight. 2. The causative agent of this disease can also be found in film preparations of the blood of patients, though it is not present in large numbers. 3. Spirochæta hebdomadis is discharged in the urine of patients having seven day fever. The number of spirochetes in the urine is great during convalescence. 4. Seven day fever is a disease found not only in the Prefecture of Fukuoka, but in many other districts of Japan as well.


Soil Research ◽  
1964 ◽  
Vol 2 (1) ◽  
pp. 29 ◽  
Author(s):  
CG Gurr

A method is given for calculating water contents of a column of soil from gamma ray data. The method is particularly useful for undisturbed field samples of unknown initial conditions. Values of water content and bulk density determined at the end of an experiment are used for calibration. To aid the calculation of large numbers of results, a nomogram has been constructed.


Sign in / Sign up

Export Citation Format

Share Document