Read Ebook: The Toxins and Venoms and Their Antibodies by Pozzi Escot M Emm Marius Emmanuel Cohn Alfred I Alfred Isaac Translator

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These toxic substances are found, according to Gamaleia, Pfeiffer, and Sanarelli, confined during the life of the microbe within its cellular envelope, and does not diffuse through this. Metchnikoff and Roux are of the contrary opinion, however, and they have prepared a toxin almost insensitive to a temperature of 100? C., and precipitable from its solutions by ammonium sulphate or strong alcohol; the toxin is a toxalbumin. This toxin is quite toxic; one-third of a cubic centimeter suffices to kill 100 Gm. of guinea-pig in 18 hours; with larger doses, death is almost immediate.

We will not dwell longer here on the toxins of microbial origin. It appears evident, however, from what has been stated above, that the great majority, if not all, of the virulent microbes manifest their virulence by means of toxic secretions. Almost every one of these toxins has been the subject of study. They would otherwise not have interested us here, where our main object was but to dwell upon the general properties.

THE VENOMS.

The venoms are toxic principles very closely allied to the microbial toxins; like the latter, they form two classes, the one alkaloidal, the other proteid, possessing a true diastatic character. They closely resemble the microbial toxins, moreover, by the fact that they are capable of being transformed into vaccins by attenuation of their virulence, by the action of heat or chemical reagents, and of leading to habituation of use and the conference of immunity. Moreover, like the various viruses, the serum of immunized animals is antivenomous, so that if injected into the veins or beneath the skin of non-immunized animals, the serum confers upon them an immunity against venom which lasts for some time.

These venoms, like the microbial toxins, possess but slight toxicity when absorbed via the stomach. Fraser, utilizing a method previously advocated, succeeded, by following this method, in vaccinating against serpent-venom by causing the absorption by animals of constantly increasing doses of venom.

It was thus possible to make the animals withstand doses a thousand times greater than the ordinary lethal dose; the blood and serums of these animals at this point possessed immunizing properties, and this property passed by heredity to the offspring, to which it is transmitted by the blood itself, and by the milk during feeding.

Along with these resemblances between the venoms and toxins, attention must be called to a very important difference. As we have already seen, the action of the toxins on the organism is always preceded by a certain period of incubation; the action of the venoms, on the contrary, is almost instantaneous, and in this respect they behave like chemical agents and alkaloidal toxins.

If the venoms are preserved in a moist condition, they change because they undergo putrefaction, which is generally the case with all diastatic substances, and particularly the toxins.

It is interesting to note that animals which have been bitten by a venomous serpent, but which, for some reason or other, have not succumbed to the venom, never recover their former condition; if they were young, their functions cease to develop, and they droop; if they are adults, their general condition remains that of stupefaction.

The effects of the bites of venomous serpents on man and animals are generally well known to the public; it is well to recall them, nevertheless. From the moment the bite has been inflicted, complete symptoms of poisoning develop, attended by a condition of extreme and increasing weakness, with vomiting, hemorrhage, and decomposition of the blood. There are, besides, particular effects which vary with every venom.

The following table by Calmette gives the comparative toxicity of various venoms, taking as the standard of comparison the quantity sufficient to kill a rabbit in three or four hours:

Naja tripudians 0.00047 Naja hag? 0.0003-0.0007 Acanthophis antarctica 0.001 Ceraste 0.0017-0.0021 Haplocephalus variegatus 0.0025 Trigonocephalus 0.0025

We shall not here enter upon a detailed study of the toxic albuminoid principles of serpent-venoms; moreover, our knowledge is rather vague, as it is, on a number of points. It will suffice us to know that, taken altogether, the active albuminoids of these venoms are numerous, and that each venom has its own particular active constituents, differing according to the species and variety of the snake.

Each one of these substances acts more or less rapidly, and may be associated with different principles which give rise to the variability of the action of these toxic agents. Among these toxic albuminoids, the most virulent appear to be true albumins and globulins, followed by the nucleo-albumins, as we have already stated; there are also found in venoms alkaloidal bases, but these principles are present only in very slight quantity. These bases are but very slightly toxic compared with the toxins that accompany them.

Fontana had remarked that snakes were quite unaffected by the bite of the viper, even when inoculated with the venom hypodermically. Physalix and Bertrand confirmed these statements, and showed that the snake perfectly resisted quantities of viper-venom capable of killing at least 20 guinea-pigs. According to these scientists, this natural immunity is due to the existence in the blood of toxic principles analogous to those of viper's venom--principles that exist in the labial glands of the snake, and pass into the blood and the fluids via the internal secretions. These writers, and also Calmette, have shown that the blood of venomous serpents becomes antitoxic when heated.

The relatively considerable immunity possessed by certain snake-charmers, and which passes for a magical gift, is due to nothing else but a natural immunity, acquired perhaps by heredity, and it always appears to follow as a result of a nonfatal snake-bite.

The poison of toads and frogs is chiefly secreted by the glands of the subcutaneous tissues of these animals; it has but a very slight action on the unbroken skin, but it rapidly inflames the nasal and buccal conjunctival mucosa. The poison is a yellowish liquid, milky and viscid, with a waxy odor and an insupportably bitter taste. It is strongly acid and caustic. When dried, the poison yields to ether a fatty matter which, when absorbed by an animal, plunges the latter into a coma that may end in death.

The residue insoluble in ether contains the non-toxic albuminoids, and ptomaines, such as methylcarbylamine, and isocyanacetic acid, resulting from the decomposition of a lecithin that appears to be soluble in ether.

The poison of the common toad acts as a paralyzant upon the heart and on the spinal marrow; that of the common frog possesses similar properties. The poison of the tritons is quite analogous to that of the toads; it contains a lecithin hydrolyzable by water with the formation of alanin, formic acid, and alpha-isocyanopropionic acid.

From the reservoir the poison is conducted to the sharp extremity of the spines by a deep channel with which each spiny ray is provided; the animal has 26 poison-sacs, two for each ray, and the sacs burst when the corresponding sting is in any manner compressed.

The poison is an odorless liquid having a slight styptic or acidulous taste, and exhibiting a bluish fluorescence; it rapidly becomes turbid.

The weevers, which are numerous on the shores of the Mediterranean Sea, and which are also met with in the northeastern portion of the Atlantic Ocean, are likewise very dangerous, which explains their popular names "viper-weever," "spiderweever," etc. These fish are provided with a double set of poisonous apparatus, the one opercular, which is the more dangerous, and the other dorsal. The opercular spine has a double channel in connection with a conical cavity hollowed out in the base of the opercular bone. The bottom of this cavity is provided with special cells which secrete the poison. The dorsal glands have a similar structure.

The poison of the weever is a liquid, limpid when the fish is alive, and turbid when dead; it has a slight bluish fluorescence, is neutral in reaction, and is coagulated by acids and bases. It acts as a paralyzant, its action being exerted on the medulla and spinal cord; it retards the heart's action.

These examples will suffice; and we will not dilate further on this subject, because, as already stated, but little is accurately known regarding the subject, and what is known may be summed up as follows: Fish-poisons always give rise to an intense pain, frequently with motor paralysis, followed by paralysis of sensation; they affect the heart, arresting it in diastole; and they are more dangerous to fish and cold-blooded animals than to mammifers.

The action of the bee-poison is very often benign, but there have been cases where death followed the infliction of numerous stings.

Our information regarding the poison of the cantharides and flies is very vague; the same is true of the poisons of various arachnids, acarides, and myriapoda. So far as spiders are concerned, it is known that their poison is an oily liquid having an acid and bitter taste, and containing a toxalbumin derived from the skin of the insect. The bite of the ordinary spider occasions simply a slight local pain, with redness; that of the large poisonous spider, however, may kill the larger animals, and even man.

Metchinkoff has confirmed these facts, and has moreover demonstrated that the blood of the scorpion possesses an undoubted antitoxic power against the poison of the insect.

The poison of the scorpion serves it to kill the insects which are its prey. Frogs and birds stung by the scorpion also generally die. A dose of 0.0005 Gm. kills a guinea-pig in less than one hour; and according to Calmette less than 0.0005 will kill a white mouse in two hours. Oxidizers destroy the toxicity of the poison. Guinea-pigs immunized against the poison of the scorpion resist perfectly very large doses of the poison.

The blood of snakes is likewise very toxic; the same is true of the blood of the viper, as 0.02 Cc. will kill a guinea-pig in two hours. All these bloods lose their toxicity when heated above 70? C. The serum of the hedgehog is peculiar in this respect; when heated at 38? C. for fifteen minutes it loses its toxicity, but it then possesses an immunizing power against the poisons.

The name "cytases" or "alexins" has been given to hemolyzing diastatic substances which are found in certain serums. It has been known for a long time that the serum of the blood of many animals destroys the red blood-corpuscles of other and different species. The chemical composition of these cytases or alexins is not yet definitely known, but the substances rank among the albuminoids; they are destroyed by a temperature of 55? to 56? C., and act only in saline solutions . The cytases or alexins, which will be studied in another volume of this collection, and which will discuss the active principles of the immunizing serums, constitute one of the numerous soluble intraleucocytary ferments, and they pass into the serous liquids of the organism only as the result of a rupture of or injury to the phagocytes.

As to the blood of the hedgehog, we have already seen that Physalix and Bertrand have shown that it may be a counter-poison towards serpent-venom under certain conditions. In its normal condition it is highly toxic.

The toxic symptoms caused by these animals become apparent in not less than twenty-four hours after ingestion. The poisoning due to these fresh meats must not, however, be confounded with that caused by tainted or spoiled meats.

PUBLISHED BY

JOHN WILEY & SONS.

Their Source, Preparation, Application, and Tests for Sensitiveness. With Tabular Summary of the Application of Indicators. Second Edition, Revised and Enlarged. 12mo, ix + 267 pages. Cloth, .00.

Chemical and Microscopical, known by their Authors' Names; together with an Index of Subjects. 8vo, iii + 383 pages. Cloth, .00.

Transcriber's Notes

Obvious typographical errors have been silently corrected, but all other variations in spelling, punctuation and accents are as in the original, with the exception of Symptomatology and symptomology which has been corrected to symptomatology.

Variations between the treatment and phrasing of headings in the table of contents and in the text have not been changed.

The book begins with a page of adverts for works by the translator, this has been moved to the end.

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