Edward Curtis Hill.

A text-book of chemistry, for students of medicine, pharmacy, and dentistry online

. (page 38 of 48)
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of water, 8 to 12 per cent, of gluten, and 60 to 70 per cent,
starch; also sugar, dextrin, fat, and salts. The protein pirin-
ciples are in the bran or cortic portion. White bread is, how-
ever, more digestible than that made from the whole wheat.
Too fresh or poorly baked bread forms a putty-like, glutinous
mass in the stomach, on which the gastric juice can have little
effect. Oats are especially rich in fats (5.14 per cent.), maize
ranking next and rice lowest.

Potatoes contain about 20 per cent, of starch. The K
salts are just beneath the skin. Eice contains 75 per cent, of
starch. Carrots possess considerable iron. Beans, pease, and
lentils contain about 25 per cent, of protein (legumin) and over
50 per cent, of starch. These legumes and garden vegetables
are apt to ferment in the bowels, owing to the large proportion



FOOD AND DIET. 409

of water and cellulose they contain. For the same reason green
vegetables must be used quickly after gathering.

Nuts are rich in fat (pea-nuts, 46 per cent.) and are hence
very nutritious, but must be well masticated. The organic acids
of ripe fruits exist therein chiefly as alkaline salts. Fruit-acids
stimulate digestion, and the cellulose, sugar, and water of fruits
help constipation, for which purpose they are best taken before
breakfast. Apples contain considerable phosphates and are di-
gested in 1 1 / 2 hours.

The volatile oils and oleoresins of condiments increase the
flavor of foods and stimulate absorption and the flow of secre-
tions, but must be used moderately, lest they irritate the mu-
cous membrane.

Eice, barley, and tapioca remain in the stomach about 2
hours; legumes and potatoes, 2 1 / 2 hours; white bread, 3 hours;
brown bread, 4 hours. The stomach should be empty of all
food in 6 hours after a meal.



COOKING.

To boil or stew meat properly the water must be boiling
when the meat is put in, then be reduced in a few minutes to
160 or 170 F. and kept so till the meat is tender: that is,
the tendons and fibrous tissues gelatinized. In this way the
albumin and globulin at the surface coagulate, preventing loss
of juices. The reverse process should be followed in making
broths; the addition of salt helps to extract myosin. Vege-
tables are better steamed than boiled, in order to retain their
special virtues. Digestion of carbohydrates is aided chiefly by
hydration of starches.

For frying purposes the oil or fat should be boiling when
the dough is put in. Otherwise the paste becomes saturated
with grease and very difficult of digestion.

Boasting is best done in the open air, where the meat be-
comes more savory, digestible, and nutritious. Broiling, or
grilling, and baking are modes of roasting. In baking bread
the glucose produced from the starch of the flour is fermented
by yeast into alcohol and C0 2 , which causes the dough to rise,
and on heating the loaf continues to expand until the gluten
is coagulated and the bread sets in a vesiculated mass. The
alcohol escapes into the air. The crust is most digestible, being
composed mainly of dextrin. Bread becomes sour from lactic
and butyric acids when fermentation is allowed to go too far
(alum prevents). A loaf of bread is not sterilized throughout
by baking.



410



PHYSIOLOGIC AND PATHOLOGIC CHEMISTRY.



BEVERAGES.

Dilute alcoholic liquors increase the flow of gastric juice
and are rapidly absorbed. They are not tissue-builders, but
tissue-savers, as shown by decrease of urea, being burned in
the capillaries into C0 2 and H 2 to the extent of 1 1 / 2 or 2
oz. daily; 1 gm. alcohol = 0.071 calorie. Hence they are of
service in some fevers. Alcoholics do not, however, give real
strength. When used continually they probably combine with
the nervous tissue of the brain, interfering with proper metab-
olism and predisposing to disease. The excessive use of malt



TABLE OF CALOKIFIC VALUES. (AFTER FEANKLAND AND JURGENSEN.
CALORIFIC VALUE OF 100 GRAMS IN CALORIES.



Apples 66.00

Arrowroot 391.20

Asparagus 18.50

Bean-soup 193.00

Boiled beef 209.00

Broiled beef 213 60

Raw beef 118.95

Beef-fat 906.90

Lean beef 156.70

Bread-crumbs 223.10

Butter 814.00

Buttermilk 41.56

Cabbage 43.40

Cakes 374.00

Cane-sugar 334.80

Carp 93.00

Carrots 41.00

Chicken-breast 106.40

Cheshire cheese 464.70

Codliver-oil 910.70

Cream 214.70

Hard-boiled egg 238.30

Yelk of egg 342.30



White of egg 67.10

Flour 393.60

Flounder 100.60

Macaroni 352.60

Mackerel 178.90

Milk 66.20

Skim-milk 39.61

Oatmeal 400.40

Omelet 236.70

Pea-meal 393.60

Potatoes 101.30

Pigeon 99.70

Green pease 318.00

Salmon 133.30

Ground rice 318.30

Trout . . . 106.40



Veal cutlets (raw) . .
" " (broiled) .
Wheat bread . .

" (toasted)
Whiting



. 142.45
. 230.50
. 281.00
. 258.80
. 90.40
Zwieback . 357.80



liquors leads to the putting on of fat, from imperfect oxidation
and elimination chiefly.

The alkaloidal beverages tea, coffee (a cup contains 0.1
gm. of caffein), cocoa, chocolate, kola, and mate are nerve-
stimulants and are closely related to uric acid. Hence their
continued use is likely to excite migraine and other uricacidemic
conditions. Tea and coffee should always be prepared by a
few minutes' infusion with nearly boiling water, as prolonged
boiling drives off the aromatic flavoring oil and causes the
water to take up a bitter astringent, tannin, a radical opponent
of eupepsia. In addition to caffein (0.8 per cent.), caffeotannic



AUTOTOXEMIA. 411

acid, and the aromatic oil, coffee-berries contain fat, legumin,
sugar, dextrin, vegetable acids, and mineral salts. On roasting,
the sugar is changed to caramel and the aroma develops. Tea
contains about 3 per cent, of thein and 13 per cent, of tannin
(more in green than black), as well as dextrin, glucose, and a
volatile oil. Cocoa is the most nourishing of these drinks, since
it contains 50 per cent, of fat and 12 per cent, of proteins.

Lemon-juice contains about .30 grains of citric acid per
fluidounce. It is of special use in scurvy, which appears to be
a mineral-acid intoxication due to an exclusive diet of meats
or cereals.



AUTOTOXEMIA.

Autointoxication, or poisoning from within the body, is
of great practical importance in the causation of various dis-
eased conditions. The agents giving rise to autointoxication
may be either pathologic chemic compounds or physiologic
products in excess of normal limits. The general rule is that
the waste-products of any organism are deleterious to it and
may cause death, sometimes suddenly, when reabsorbed in suffi-
cient amount.

The toxic endogenous substances giving rise to autotoxemia
include the fatty acids (beta-oxybutyric causes diabetic coma),
aromatic phenols (intestinal autointoxication), tyrosin (hepatic
insufficiency), purin bases (uricacidemia, migraine, and gout;
guanin from cancerous degeneration causes coma), diamins
(putrescin and cadaverin in gangrene and carcinoma); mucin in
myxedema; neurin in Addison's disease; the amins (especially
trimethylamin), aceton, special alkaloids, and leucomains, and
the toxins generated by the colon bacillus, which is a constant
habitant of the bowel.

The etiologic classification of Albu is as follows: Arrest of
organic function (myxedema, pancreatic diabetes, Addison's
disease, acute yellow atrophy); anomalies of general metab-
olism (gout, oxaluria, diabetes); retention of physiologic meta-
bolic products (uremia or potassemia, eclampsia, cholemia, as-
phyxia, extensive burns); overproduction of physiologic and
pathologic products (overwork, diacetemia, ammonemia, cysti-
nuria, etc.); decomposition of food-substances arising from
maldigestion. The last class is most common, and is usually
accompanied by constipation, indicanuria, and neurasthenic
symptoms.

Lithemia, or biliousness, is, generally speaking, the mani-
festation of an overworked and long-suffering liver. The thy-



412 PHYSIOLOGIC AND PATHOLOGIC CHEMISTRY.

roid gland is involved in myxedema, cretinism,, cachexia stru-
mipriva, and possibly exophthalmic goiter; the pancreas in dia-
betes mellitus; the liver in jaundice or cholemia, lithemia,
acute yellow atrophy, and icterus gravis; the kidneys in uremia
and eclampsia; the adrenals in Addison's disease; the lungs in
C0 2 poisoning from, interference with respiration; the gastro-
intestinal tract in the depressed nervous conditions accompany-
ing constipation, indicanuria, and oxaluria; the skin in the
phenomena following severe burns of large surfaces; and the
pituitary gland perhaps in acromegaly.

The manifestations of autotoxemia in any given case are
usually manifold, and not confined to one organ. Nervous
symptoms are the most frequent, and comprise headache, ver-
tigo, syncope, irritability, insomnia, hypochondria, stupor, coma,
delirium, spasms or convulsions, paralysis, melancholia, and
mania; polymyositis has been noted in a few instances. Com-
mon cardiac symptoms are tachycardia, bradycardia, and arhyth-
mia. The breathing may be stertorous or of the Cheyne-Stokes
type. The temperature may be pyretic or subnormal, usually
the first. Digestive symptoms include anorexia, nausea, vomit-
ing, eructations, diarrhea, constipation, and colic. Toxemic
disturbances of the urinary tract are manifested by albuminuria,
hematuria, hemoglobinuria, choluria, acetonuria, diaceturia,
and oxaluria. The skin may be anemic, jaundiced, or bronzed,
and not seldom shows an erythematous eruption. Cachexias
are frequent, particularly those of cancer, diabetes, chlorosis,
leukemia, pernicious anemia, and the uric-acid diathesis. In-
fantile rickets, purpura, scurvy, and pernicious anemia are often
of autotoxemic origin. Chlorosis is said to be a sequel of
copremia.

INFECTION AND IMMUNITY.

Most infectious diseases are known to be caused by the
presence in the body of specific bacteria, which generate soluble
poisonous bases, or toxins, that act as the direct cause of
all the morbid symptoms. The term intoxication is applied
when infectious microbes remain localized and only their toxic
products enter the system. A certain bacterium may produce
one or more toxins. Thus, the tetanus bacillus is responsible
for four distinct toxins: tetanin, tetanospasmin, tetanolysin,
and one unnamed. The relative toxicity of toxins in general
is enormous; the diphtheritic toxin can produce lethal results
in a living being 20,000,000 times its own weight. Tetanus
toxin is 300 times as toxic as strychnin. The incubation period
of an infectious disease is the period during which sufficient



INFECTION AND IMMUNITY. 413

toxins are being formed to produce an appreciable constitu-
tional effect.

When diphtheria toxin is injected into a susceptible ani-
mal,, as the horse, in gradually increasing doses, the said animal
acquires a marked tolerance to the poison, so that an amount
can finally be injected which at first would have proved quickly
fatal. The serum of the animal's blood also acquires the prop-
erty of protecting other animals against diphtheria when in-
jected subcutaneously in sufficient dose. Such serum when
concentrated is known as antitoxin, and is standardized by
physiologic tests against a given quantity of toxin: both being
injected at the same time into guinea-pigs. A normal anti-
toxic unit is equivalent to 1 c.c. of normal serum, and will
counteract 100 doses of toxin fatal to the guinea-pig.

According to the Ehrlich theory of immunity, the presence
of toxins in the blood stimulates the protoplasm of the leuco-
cytes and the fixed tissues to an intramolecular migration of
atoms to a more stable position. In this change are thrown
out certain side-chains, or receptors, which have a particular
destructive affinity for the given toxin and combine with and
neutralize it. The molecules are not broken apart if the stimu-
lation is slight, but protoplasmic resistance to the toxins is in-
creased, as exemplified by vaccination. Under increased stim-
ulus by the toxins myriads of these side-chains are liberated
into the serum, giving it antitoxic properties, and constituting
the more or less perfect active artificial immunity observed after
one attack of a contagious disease. It is claimed that the
amount of antitoxin set free can be augmented by the admin-
istration of agents (pilocarpin) which stimulate cell-activity.
Antitoxins may also be formed by the stimulating action of
non-bacterial proteins (ricin, abrin).

If, on the other hand, as in malignant cases, the toxin is
overwhelming in force and amount, reaction is paralyzed, no
side-chains are evolved, and the patient quickly succumbs.
Passive immunity is that conferred by the injection of anti-
toxins (diphtheria, tetanus, antistreptococcic, etc.), and is of
much snorter duration than active immunity, since it is not
re-enforced by fresh supplies from the cells and is gradually
eliminated.

The natural immunity which some persons and animals
exhibit toward certain infections is explained on the entire
absence of receptor formation and hence of combination with
the toxins; in other words, the toxins do no harm because the
protoplasm is not affected by them. It is further possible for
a subject to be susceptible to the toxins of a disease when



414 PHYSIOLOGIC AND PATHOLOGIC CHEMISTRY.

directly injected and yet not amenable to ordinary inoculation
by the germs of the disease, since the latter may not thrive in
their environment with sufficient vigor to produce toxins in
any quantity.

Snake-venoms belong to the class of toxalbumins, and the
protective and curative action of antivenene is probably a bio-
chemic reaction analogous to that of antitoxins. It is a curious
fact that venom when taken by the stomach protects against
snake-bites, and the same is true of antivenene, but antitoxins
are ordinarily best given hypodermically. Vaughan believes
that toxins and antitoxins are nucleins, neutralizing each other
chemically.

Chemically speaking, tubercle bacilli consist of protoplasm
inclosed within a waxy capsule. The toxic products of the life-
processes of tubercle bacilli include a systemic poison, a fever-
producing agent, and a necrotic. Tuberculin (the old T. 0.,
not T. R.) is a 4- to 7-per-cent. glycerin extract prepared from
old, concentrated culture-media of tubercle bacilli. It contains
salts, pepton, albumose, and other undefined proteins, one of
which is a fever-producing toxin, and is used for diagnostic pur-
poses in the dose of 1 / 2 or 1 mg.

HEMOLYSINS.

It has been discovered that the serum of one animal in-
jected with the blood of another becomes toxic for the animal
whose blood was injected, agglutinating and dissolving the red
corpuscles of the blood. Such toxic substances, when produced
by the injection of heterologous blood, are termed heterolysins.
When the injections are in the same species isolysins are
formed. Autolysins have so far not been produced. The serum
of many animals is naturally cytotoxic and hemolytic, and the
same is true of snake-venoms. Repeated injections in increas-
ing dosage lead to the development of an antitoxic resistance
to the poisons. Certain toxins (tetanolysin) contain two sets
of molecules, one binding the antitoxins (haptophorous) and
one producing hemolysis (toxophorous). Leucocytolysins are
similar in action to hemolysins, dissolving the white blood-cells,
however, without previous agglutination. Various theories of
cytolysis have been proposed. One is that in immune serums
there are two distinct substances, namely: the specific immune
or anti- body (globulolytic and bacteriolytic), which is not de-
stroyed by heat; and the non-specific alexin or complement,
which is destroyed at 50 to 60 and which exists preformed
in all blood. In hemolysis it is claimed that the anti-body is



INFECTION AND IMMUNITY. 415

bound by the stroma of the red corpuscles or perhaps links the
alexin to the cells. Another explanation of hemolysis by im-
mune serums is through a sudden disturbance of osmotic equi-
librium.

Anticytotoxins is the term applied to substances that neu-
tralize hemolytic serums. They are produced, in a similar way
to antitoxins, by injecting hemolytic serums in increasing doses
into susceptible animals. They seem to include both anti-
alexins and anti-immune bodies.

Various other toxic and antitoxic substances such as epi-
theliolysin, spermotoxin, and nephrolytic serum are developed
by the natural resistance of the cells to outside influences. It
is possible that in some cases sterility depends on the presence
of spermotoxic substances in woman's blood.



BACTERIOLYSINS.

Bacteriolysins are complex substances composed of a pep-
tonizing ferment and a bacterial derivative. They have a di-
gestive and antibacterial action, but no effect on toxins, which
they set free, sometimes aggravating the condition.

Destruction of bacteria may be due to plasmolysis or plas-
moptysis (spewing out of cell-contents), depending on osmotic
disturbances. Thus the diplococcoid form of colon bacilli said
to be found in cirrhotic livers and the accompanying ascitic
fluid are perhaps degenerating forms due to plasmolysis. These
dead bacilli and bacillary fragments tend to take up iron, form-
ing pigment-granules. Bacteriolysins may further be produced
by the digestion of bacteria with peptonizing ferments. These
lysins are pptd. by acetic acid and dissolve again in alkaline
water.

AGGLUTINATION.

This curious property, forming the basis of the Widal test
for typhoid fever, appears to be due to the action of agglutinins
of unknown origin, so changing the bacterial membrane as to
render it sticky. The agglutinating property of serum is not
destroyed by heating to 180. Its homologous nature is not
characteristic, since typhoid bacilli are clumped by diphtheria
antitoxin.

The agglutination of blood-corpuscles in coagulation is
most marked in pneumonia, rheumatism, erysipelas, and ty-
phoid. Owing to the firmness of the clot in these cases, the
buffy coat is unusually distinct.



416 PHYSIOLOGIC AND PATHOLOGIC CHEMISTRY.



QUESTIONS ON PHYSIOLOGIC AND PATHOLOGIC CHEMISTRY.

1. Why is saliva frothy and viscid?

2. What is the color of the stools in jaundice?

3. How detect starch in feces? Fat? Mucus? Casein?

4. Why does the sweat often smell sour in summer?

5. How does taking HC1 diminish the amount of NH 3 in the urine?

6. What effect does muscular exertion have on the alkalinity of
the blood?

7. How does (NH 4 ) 2 C 2 O 4 , added to freshly drawn blood, prevent,
its coagulation?

8. Why does a sip of vinegar cause pain in mumps?

9. What causes the film on the surface of saliva on standing?

10. How does deficient motility interfere with stomach-digestion?"

11. Why not feed a young baby crackers?

12. Why do we need to add salt to our food?

13. How detect with certainty the presence of saliva in the stomach-
contents ?

14. Why is whole-wheat bread more nutritious and less digestible
than white bread?

15. Why are sterilized milk and artificial infant-foods likely to-
produce rickets and scurvy?

16. Why is it best to boil potatoes in their skins?

17. What kind of diet is best for hypochlorhydria?

18. Why is toast more digestible than untoasted bread?

19. Why must the blood be saline? Alkaline?

20. What chemic effects have fruits on blood and urine?

21. Explain the chemistry of infantile colic.

22. What chemic compounds are present in hair?

23. Why do the nursing mother's teeth often decay rapidly?

24. Write formulas for xanthin, theobromin, caffein (them), and
uric acid.

25. Gall-stones are most frequent in fat, elderly women. Why?

26. To reduce obesity what kinds of food should be avoided?

27. Why is fracture in children often of the "green stick" type?

28. What chemic changes accompany muscular contractions?

29. What is the chemistry of atheroma?

30. What is the difference in composition between blood- serum and
plasma ?

31. What element is indicated medicinally in anemic conditions?

32. What is the color of a person's lips poisoned by "blowing out
the gas"?

33. Explain the symptoms of "heart-burn" and "water-brash."

34. Why do milk and other proteid foods give relief in hyperchlor-
hydria ?

35. State the chemic distinctions between gastric ulcer and gastric
cancer.

36. What hydrocarbon is found in the body? What alcohol? What
ethers ?

37. Compare the composition of human and bovine milk.

38. What are the chemic differences between whey and butter-milk ?

39. How does chyle differ from lymph?

40. Give some chemic reasons for the symptoms of Addison's
disease.

41. On what various factors does diabetes mellitus depend?



QUESTIONS. 417

42. How distinguish with certainty blood in the stools from other
coloring matter?

43. Why is yellow sputum usually more liquid than white?

44. What are the chief distinctions between exudates and transu-
dates?

45. How do potatoes cure scurvy?

46. If 1 gm. urea = 3 gm. albumin, how much protein food does
a laboring man weighing 140 pounds require daily?

47. What advantages have cheese and pulses over meats in uric-
acid cases?

48. Name ten foods especially good for students, and give reasons.

49. Define internal respiration.

50. What substances act as fuel foods?

51. What is the office, chemically speaking, of digestion?

52. Why is it sometimes advisable to prescribe medicines with
ginger, capsicum, nutmeg, and other spices?

53. Explain from the physic standpoint the removal of dropsies by
diuretics.

54. How may an attack of uremia be pptd. by the free use of digi-
talis after tapping an ascites?

55. Distinguish between active immunity, passive immunity, vac-
cination, and natural immunity.

56. W 7 hy do fats generate more heat in the body than carbohy-
drates or proteins?

57. Why is the lowest daily range of normal body-temperature in
the early morning?

58. Make out a diet-table for 3500 calories, using roast beef, wheat
bread, potatoes, milk, and butter.

59. Why should diphtheria antitoxin be given as early as possible?

60. How does the addition of borax or Na 2 CO 3 delay the souring of
milk?

61. Why do infants become anemic when limited too long to a milk
diet?

27



CLINIC CHEMISTRY.



GASTRIC JUICE.

FOE clinic purposes the stomach-contents are usually
drawn with the soft stomach-tube an hour after taking Ewald's
test-breakfast. This consists of a one-ounce dry roll or two
pieces of toast without butter, and 2 / 3 P in t (500 c.c. better) of
warm water or weak tea without milk or sugar. The double
test-meal of Hemmeter consists of a full meal at 8 A.M.; Ewald's
test-meal at 12 M.; withdrawal of stomach-contents and exami-
nation at 1 P.M. Disappearance of the entire breakfast points
to normal digestion; absence of all proteids, with presence of
considerable carbohydrates = hyperchlorhydria; absence of all
carbohydrates, with presence of some beef and egg = hypo-
chlorhydria or anacidity; presence of entire meal, with the milk
perhaps all uncurdled = achlorhydria and absence of ferments
and glandular atrophy.

The quantity of gastric juice obtained in this way is nor-
mally about 40 c.c.; more than 60 c.c. or less than 20 c.c. is
pathologic. The former condition points to dilation and motor
insufficiency; the latter, to too rapid emptying of the viscus.
The liquid should be filtered at once and examined as soon as
possible.

The reaction is tested with litmus-paper, and is normally
frankly acid. The presence of free acids is shown by congo-red
paper, which turns deep blue with 1 part in 50,000 of mineral
acid; violet, with organic acids. Tropeolin 00 in aqueous solu-
tion is a dark yellow-red or brown fluid, changed to pink by
1 to 4000 of free HC1, giving a bluish residue on drying; to a
straw color by acid salts. Benzopurpurin (6 B) paper is turned
an intense dark brown by mineral acids. A 1 to 2000 aqueous
methyl-violet solution added to the specimen yields a copper-
blue color with HC1; a violet-blue with organic acids.

Free HC1 can also be shown by the addition of 3 or 4
drops of a 5-per-cent. alcoholic solution of dimethyl-amido-
azobenzol, which gives a pink color if this acid is present in the
free state, while a yellow color indicates its absence. Giinz-
burg's reagent is prepared by dissolving 1 gm. vanillin and 2
gm. phloroglucin in 100 c.c. of alcohol. The solution to be
tested is placed in an evaporating dish, 2 or 3 drops of the
(418)



GASTRIC JUICE. 419

reagent added, and the mixture evaporated to dryness just
below the b.p. on the water-bath or over a small flame. A
purple or pink-red color shows free HCL Boas's reagent is



Online LibraryEdward Curtis HillA text-book of chemistry, for students of medicine, pharmacy, and dentistry → online text (page 38 of 48)