QUANTITATIVE STUDIES ON THE PRECIPITIN REACTION : EFFECT OF SALTS ON THE REACTION

1. A quantitative study has been made of the effect on the precipitin reaction between the specific polysaccharide of Type III pneumococcus and the homologous antibody of salt concentrations ranging from O.1 M to 1.79 M, including the effect of ions of higher valence. 2. Within these limits, observed decreases in precipitated antibody with increasing salt concentration appear to be due to a decrease in the amount of antibody combined with the S III, rather than to an increase in solubility of the S III-antibody compounds. 3. The egg albumin-antibody reaction is far less sensitive to changes in salt concentration than is the S III-antibody reaction.     

THE EFFECT OF SODIUM CHLORIDE ON THE CHEMICAL CHANGES IN THE BLOOD OF THE DOG AFTER OBSTRUCTION OF THE CARDIAC END OF THE STOMACH

A study is reported of the effect of different methods of treatment on the toxemia of cardiac obstruction. The average duration of life of untreated dogs is 3 days. Three dogs treated with 1 per cent salt solution subcutaneously lived 32, 36, and 45 days respectively without developing a toxemia. 2 per cent glucose similarly given, does not alter the course of the toxemia. Concentrated salt solution in small quantities given directly into the jejunum prevents the marked rise in non-protein nitrogen but does not materially prolong life. Release of the obstruction does not change the course of the toxemia in untreated animals. The subcutaneous injection of 1 per cent sodium chloride solution after release of the obstruction causes a rapid return of the blood to normal and allows the animal to recover. A similar amount of fluid given as 2 per cent glucose does not alter the course of the toxemia after release of the obstruction.     

THE FROST RESISTANCE OF HOOP PINE

Drought deaths on shallow soils have been a feature of the forest during arid cycles deficient in winter rainfall. These sites have been free of deaths since 1952.

Deaths have occurred more or less continuously since early 1952 in gullies, soaks, and flats throughout the forest, mostly in very vigorous forest, which is equal to the best development of P. radiata in the Adelaide Hills.

Analysis of foliage samples indicates significant amounts of chloride, the upper limit of apparently unaffected needles being 0.5 per cent, chloride. Affected foliage has a characteristic scorched appearance due to browning or death of the top of the needle.

Affected trees cover a range of ages from 5 to 39 years over several geological formations with various aspects and the conclusion is that there has been a climatic upset. Rainfall data indicate a very high water-table in 1951, one condition necessary to salt uptake.

Abnormal salt concentration in that water-table has been possibly caused by three factors concentrating the annual accession of cyclic salt which is present in all the rainfall over southern Australia. Other factors may have been contributory.

The “accident” of early 1952 appears to be a coincidental combination of several factors which may never occur again. Similar deaths in all the forest reserves of the Adelaide Hills indicate the widespread nature of the climatic upset and the necessity for further investigation.

Afforestation schemes on poorly drained country near the coast of southern Australia may well have to consider the relation between ever-present cyclic salt and fast-growing conifers, the large water requirements of which tend to exert a concentrating effect upon that salt in the soil water.     

一种甘氨酸盐消毒液杀菌效果观察

目的观察一种以二辛基甘氨酸盐为主要杀菌成分的消毒液杀菌效果。方法采用悬液定量杀菌试验方法,对该消毒液进行了实验室检测。结果以含20g/L二辛基甘氨酸盐的该消毒液作用10min,对悬液内金黄色葡萄球菌、大肠杆菌的平均杀灭对数值均5.00。以相同浓度的该消毒液对物体表面作擦拭消毒并作用5min,对物体表面自然菌的平均杀灭对数值均1.00。该消毒液原液经54℃放置14d后,对金黄色葡萄球菌杀灭效果无变化。结论以二辛基甘氨酸盐为杀菌成分的该消毒液对细菌繁殖体具有良好的杀菌效果,储存性能稳定。     

THE EFFECT OF SERUM UPON THE GERMICIDAL ACTION OF SOAPS

1. Far more information about the effect of serum or other substances upon the germicidal action of soaps can be obtained by determining the germicidal titers over a wide range of pH than by determining the titer at a single pH. In this way a characteristic curve for each test substance is obtained. 2. The curve for a particular concentration of serum bears a definite relationship to the curve for salt solution (buffer) alone. Wherever the titer in salt solution is high, very small amounts of serum greatly diminish that titer. Wherever the titer in salt solution is low, small amounts of serum leave the titer unchanged. Thus small additions of serum flatten the curves and make them more nearly horizontal. If further large amounts of serum are added, a further reduction in titer takes place at all reactions. 3. The calcium of serum has only a very slight effect upon the soap titer. 4. The protein of serum is probably inhibitory to soaps; but the curve for partially defatted serum, and the curves for other protein substances tested, do not run parallel to the serum-soap curves. 5. The various lipoids that are known to be present in serum are inhibitory to the action of soaps, both as emulsions and as clear solutions. 6. The action of serum upon soaps may be regarded as a complex reaction, in which lipoids, protein, and, to a lesser extent, calcium salts take part. Their effect is due to the fact that these substances, by combining with the soaps, remove them from the field of germicidal action.     

THE EFFECT OF IRRITATION ON THE PERMEABILITY OF THE MENINGES FOR SALVARSAN

The subdural injection of normal salt solution, normal serum, serum salvarsanized in vivo or weak solutions of cyanide of mercury does not demonstrably increase the permeability of the spinal cord or brain for salvarsan which is circulating in the blood at the time of the subdural injection.     

STUDIES ON TYPHUS FEVER : XII. THE PASSIVE IMMUNIZATION OF GUINEA PIGS,INFECTED WITH EUROPEAN VIRUS,WITH SERUM OF A HORSE TREATED WITH KILLED RICKETTSIA OF THE MEXICAN TYPE

Under uniform diet conditions the normal bile fistula dog will eliminate pretty constant amounts of cholesterol—about 0.5 to 1.0 mg. cholesterol per kilo per 24 hours. Diets rich in cholesterol (egg yolk) will raise the cholesterol output in the bile but compared to the diet intake (1.5 gm. cholesterol) the output increase in the bile is trivial (5–15 mg.). Calves'' brains in the diet are inert. Bile salt alone will raise the cholesterol output in the bile as much and often more than a cholesterol rich diet. Bile salt plus egg yolk plus whole bile give maximal output figures for bile cholesterol—60 mg. per 24 hours. Liver injury (chloroform) decreases both bile salt and cholesterol elimination in the bile. Blood destruction (hydrazine) fails to increase the bile cholesterol output and this eliminates the red cell stroma as an important contributing factor. Certain cholagogues (isatin and decholin) will increase the bile flow but cause no change in cholesterol elimination. The ratio of cholesterol to bile salt in the bile normally is about 1 to 100 but the bile salts are more labile in their fluctuations. The ratio is about reversed in the circulating blood plasma where the cholesterol is high (150–300 mg. per cent) and the bile salt concentration very low. Cholesterol runs so closely parallel to bile salt in the bile that one may feel confident of a physical relationship. In addition there is a suspicion that the bile cholesterol is in some obscure fashion linked with the physiological activity of hepatic epithelium.     

VENOM HEMOLYSIS AFTER SPLENECTOMY,INCLUDING THE RESISTANCE OF THE ERYTHROCYTES OF NORMAL DOGS TO THE HEMOLYTIC ACTIVITY OF COBRA VENOM

1. The resistance of erythrocytes of dogs to the hemolytic activity of cobra venom is increased after splenectomy. 2. This increased resistance was observed as early as 4 days after splenectomy and usually persisted for a period of about 3 weeks, when the resistance gradually decreased to normal or slightly beyond. 3. The decrease of resistance to the hemolytic activity of venom for the erythrocytes of splenectomized dogs following the primary increase is apparently coincident with the anemia following splenectomy. An intercurrent infection, such as distemper, tends to reduce the resistance of erythrocytes to venom. 4. An increased resistance of the erythrocytes to hypotonic salt solutions was found with all the splenectomized dogs in which these tests were made. Increased resistance to hypotonic salt solutions apparently persists for a longer period than the increased resistance to cobra venom. 5. As the lysis of erythrocytes by venom is dependent upon the presence of certain lipoidal substances within the cells, and as the spleen may exercise an influence over the lipoidal contents of corpuscles and serum, it is suggested that the increased resistance of erythrocytes to the hemolytic activity of venom after splenectomy is due to alterations in the lipoid content of the erythrocytes.     

STUDIES IN AGGLUTINATION : III. ON THE MECHANISM OF THE AGGLUTINATION OF BACTERIA BY SPECIFIC AGGLUTINATING SERUM.

From the foregoing evidence, specific bacterial agglutination may be conceived of as follows: When bacteria are mixed with their homologous agglutinative sera, specific union between organism and agglutinin occurs. This interaction consists of specific coating of the bacteria by globulin. By virtue of the fact, noted by Loeb and illustrated in Fig. 6, that protein film formation gives the coated particle the characteristics of denatured protein, the bacteria now take on the character of particles of denatured globulin. Particles of denatured protein flocculate whenever their charge is reduced by electrolyte to a critical level lying somewhere between 12 and 14 millivolts. This is true even when the salt is strong, as, unlike bacterial particles, their cohesive force is not readily depressed by salt. The sensitized bacteria, now being essentially particles of denatured protein, likewise agglutinate as soon as their charge is reduced by electrolyte to this potential level.     

OBSERVATIONS UPON THE ACTION OF SALTS ON THE CATALASE OF THE BLOOD IN RABBITS

Bicarbonate of soda fed in varying quantities over a period of months has no direct effect upon the catalytic activity of the blood. When fed to rabbits, it invariably causes a slight albuminuria and occasional casts. The kidneys of pregnant animals, especially in the later stages of pregnancy, seem to be more susceptible to this salt, and in some instances there may be complete suppression of urine followed by death. In these cases there is a decline in the catalytic activity of the blood similar to that observed in cases of acute nephritis, following the administration of uranium nitrate. The subcutaneous injection of salts is impracticable on account of the slow absorption. In intravenous injections it is important to make observations during the injection and at short intervals after the injection has been discontinued, since there is a rapid compensation on the part of the organism with a return of the normal catalytic activity of the blood. The simple diluting effect brought about by the injection of distilled water into the circulation manifests itself as a slight transitory decrease in the catalytic activity of the blood. This must be taken into consideration when estimating the effect of the injection of solutions of salt upon the catalase of the blood. Salts, such as sodium chloride, sodium bicarbonate, sodium sulphate and potassium iodide, acids, such as sulphuric, and alkalies, such as sodium hydrate, cause a definite decrease in the catalytic activity of the blood. This decrease varies directly with the concentration of the salt. The organism compensates rapidly and brings about a return to the normal activity. This compensation becomes less and less complete as larger quantities or repeated infusions are made. For example, twenty cubic centimeters of a five per cent. bicarbonate of soda solution causes a marked fall in the catalytic action of the blood. This is rapidly recovered from in from one to five minutes, and then a much more marked fall in the activity, requiring a longer time for compensation, occurs after the injection of six cubic centimeters of the same solution. It is of interest to note that sodium sulphate and potassium iodide, which have been shown to accelerate the catalytic activity of liver extract in the test-tube, have an inhibiting effect on the action of the blood when injected intravenously. This is only another instance of the dangers to be encountered from the immediate application of test-tube experiments to the living organism. The inhalation of carbon dioxide gas, even until convulsions are manifested, is without effect on the catalytic activity of the blood. On the other hand, there is a definite decline in this activity following the administration of illuminating gas. In this respect our results are directly at variance with those of Jolles.     

绿脓杆菌污染调查用选择培养基的研究

新研制的改良NAC培养基,经医院拖布标本检测,其对绿脓杆菌的检出阳性率与NAC培养基比较,虽无显著差别。但改良NAC培养基上的绿脓杆菌菌落较大,绿色素亦较显著,分离时易于识别。     

QUANTITATIVE STUDIES ON ANTIBODY PURIFICATION : I. THE DISSOCIATION OF PRECIPITATES FORMED BY PNEUMOCOCCUS SPECIFIC POLYSACCHARIDES AND HOMOLOGOUS ANTIBODIES

1. Quantitative data are given on the effect of changes in hydrogen ion concentration and of salt solutions of high concentration on certain immune precipitates obtained at lower salt concentration. 2. Advantage is taken of the shift in reaction equilibrium brought about by the salt in the case of pneumococcus carbohydrate-anti-carbohydrate precipitates to enable the preparation, in a single step from unconcentrated serum, of antibody solutions in which up to 93 per cent of the total nitrogen is immune nitrogen. The method permits successive absorptions of a serum to be made with the same specific precipitate. 3. A modification of Felton''s alkaline earth hydroxide dissociation procedure is proposed which yields highly purified antibody with precipitates which have been subjected to several successive salt dissociations.     

FURTHER EVIDENCE OF THE TOXICITY OF NaCl : INCREASED BLOOD PRESSURE AND MORTALITY IN THE SPONTANEOUSLY HYPERTENSIVE RAT

The spontaneously hypertensive rat (SHR) of Okamoto and Aoki (4) develops significant hypertension without added dietary salt. Many patients with hypertension have little or no alteration in blood pressure from increments or decrements of salt intake. Such observations have led to a widespread belief that dietary NaCl is important in hypertensives only if blood pressure changes are observed after changes in NaCl intake. Such a simplistic view of hypertension fails to take into account the possibility that morbidity and mortality might be lowered by restricting dietary NaCl, without a concomitant lowering of blood pressure. The effect of a high NaCl intake for periods up to 1 yr has been studied in the SHR with the following conclusions: (a) NaCl accelerated the rate at which hypertension developed in both sexes. (b) The ultimate levels of blood pressure reached by males on either high or low salt diets were similar, however. (c) In females, (1) on high NaCl the average blood pressure ultimately became indistinguishable from males whereas (2) on low NaCl pressure remained significantly lower than that of males. (d) The addition of NaCl to the regimen had a devastating effect on mortality of both sexes and was not directly correlated with the level of blood pressure. Earlier reports were reviewed bearing on the possibility that NaCl is inimical to blood vessels without a necessary relationship to its hypertensinogenic effect. It was concluded that restriction of dietary NaCl would reduce morbidity and mortality in hypertension, whether or not blood pressure was reduced by such measures.     

THE COMPATIBILITY OF CALCIUM PHOSPHATE IN PAEDIATRIC TPN INFUSIONS

The addition of calcium phosphate to total parenteral nutrition (TPN) infusions is investigated with particular reference to factors affecting the solubility of the salt. Recommendations are made about the most appropriate method for adding calcium phosphate to paediatric and neonatal TPN products.     

THE FILTRABILITY OF YELLOW FEVER VIRUS AS EXISTING IN THE MOSQUITO

The virus of yellow fever as it exists in Aëdes aegypti mosquitoes, both in their so-called infective stage and in the intermediate condition termed the "incubation period", is capable of passing through Berkefeld N filters when suspended in normal monkey serum, although earlier investigators have shown that the virus from infective mosquitoes will not do so when suspended in physiological salt solution. The virus of yellow fever as it exists in mosquitoes behaves with regard to filtration through Berkefeld N filters as does the virus in the blood of infective monkeys.     

BENIGN AND MALIGNANT HYPERTENSION AFTER ADRENAL ENUCLEATION IN THE RAT : RELATIONSHIP TO SALT INTAKE, RESPONSE TO HYDROCHLOROTHIAZIDE, AND SIMILARITY TO ESSENTIAL HYPERTENSION

Adrenal-enucleated, mononephrectomized rats given a high salt diet rapidly develop malignant hypertension, characterized by the presence of necrotizing vascular lesions in a number of organs and tissues. If a normal salt intake is provided, or if hydrochlorothiazide is given together with a high salt diet, there is, instead, the delayed onset of benign hypertension which either stabilizes or increases in intensity extremely slowly; Such animals display few, if any, pathologic vascular changes other than occasional focal glomerular hyalinization, show insignificant cardiac enlargement, and do not exhibit alterations in the serum sodium or potassium. Occasional animals behave atypically and develop malignant hypertension despite normal salt consumption, demonstrating that in susceptible rats excess salt is not essential to this disorder. Hydrochlorothiazide given to rats that imbibed distilled water postoperatively prevented hypertension entirely for 97 days, when one of eight rats developed mild hypertension and some others reached what is regarded as a prehypertensive range. It is concluded that adrenal regeneration provides a physiological milieu favorable to the development of benign hypertension, which is not, as a rule, manifest until regeneration is complete. Salt excess converts the response into one in which malignant hypertension begins during regeneration and worsens rapidly thereafter until death. The course and findings are compared with those of the benign and malignant phases of clinical essential hypertension, and the implications of the similarities are discussed.     

EFFECT OF VARIOUS AGENTS ON THE BLOOD FLOW THROUGH THE CORONARY ARTERIES AND VEINS

The results obtained show that adrenalin, transfusion with salt solution, and the inhalation of tobacco smoke caused an increased circulation in the coronary vessels. Amyl nitrite and nitroglycerin produce the opposite effect. Digitalis, strophanthus, caffeine, and theobromine give no change in the velocity of circulation. We can conclude from the results that the blood pressure is the main element which influences coronary circulation, while the other factors play only a minor part in its variations.     

THE OPTIMUM HYDROGEN ION CONCENTRATION FOR THE GROWTH OF PNEUMOCOCCUS

1. The optimum hydrogen ion concentration for the growth of the various types of pneumococcus is a pH of about 7.8. 2. The limiting hydrogen ion concentrations for the growth of pneumococcus are a pH of 7.0 and a pH of 8.3. 3. Phosphates used in adjusting reactions of media retard growth if present in a concentration greater than 0.1 molecular. 4. Culture media for pneumococci should, therefore, have an initial reaction between a pH of 7.8 and 8.0 and a total salt concentration not exceeding 0.1 M.     

ABSORPTION FROM THE PERICARDIAL CAVITY

1. Physiological salt solution is absorbed from the pericardial cavity of medium-sized rabbits at a rate of approximately 1.3 cc. per hour. This absorption is via the subepicardial blood capillaries. 2. Rabbit serum and horse serum are absorbed extremely slowly—an indication of the low-grade lymphatic drainage of the pericardial sac. 3. Graphite particles of bacterial dimensions are also removed very slowly. Such particles enter lymphatics only after phagocytosis. The lymphatics in the basal part of the pericardium are the principal source of drainage. Subepicardial lymphatics are entered with difficulty from the pericardial cavity.     

THE INFLUENCE OF TEMPERATURE AND FLUID MEDIUM ON THE SURVIVAL OF EMBRYONIC TISSUES IN VITRO

1. Embryonic chick and rat tissues preserved at temperatures ranging from –7° to +20° C. live longest at about +6° C. The duration of life under the most favorable conditions is less than twenty days. 2. The kind of isotonic medium used,—plasma serum, Ringer solution, or normal salt solution,—does not appreciably influence the period of survival. The quantity of medium in proportion to tissue is similarly without marked effect.