ETIOLOGY OF YELLOW FEVERNoguchi, Hideyo
doi: 10.1084/jem.30.2.87pmid: 19868352
Examinations of fresh blood from yellow fever patients by means of the dark-field microscope, made in more than twenty-seven cases, revealed in three cases the presence of Leptospira icteroides . In no instance was a large number of organisms found, a long search being required before one was encountered. The injection of the blood into guinea pigs from two of the three positive cases induced in the animals a fatal infection, while the blood from the third positive case failed to infect the guinea pigs fatally. Careful but by no means exhaustive dark-field searches for the leptospira with fresh specimens of blood from the remaining cases of yellow fever ended without positive findings, although four of the specimens, when injected into guinea pigs, caused a fatal leptospira infection. Stained blood film preparations from the corresponding cases were also examined, but the percentage showing the leptospira in the blood was no greater than that found by examination in the fresh state with the dark-field microscope. In fact, owing to the defective stains that were available at the time of the investigation a great many slides did not take the proper coloration with Giemsa's or Wright's stain and could not be relied upon. Regarding the presence of Leptospira icteroides in various organs both dark-field and stained films were examined. In only one instance so far a few organisms were detected in the emulsion of liver taken shortly after death from a case dying on the 4th day of yellow fever. This part of the work will be reported later upon completion. Examinations of the urine from different cases of yellow fever were made both by dark-field microscope and by inoculation into guinea pigs. The results were totally negative in thirteen cases, including many convalescents, but in one case one of the guinea pigs inoculated with 10 cc. of the urine came down on the 15th day with suggestive symptoms (suspicion of jaundice, and some hemorrhagic and parenchymatous lesions of the lungs and kidneys). This specimen showed no leptospira by dark-field examination. In experimental infection of guinea pigs with Leptospira icteroides the blood became infective in many instances 48 hours after inoculation, and was always infective after 72 hours. The liver and kidney become infective simultaneously with the blood. Detection of the organism by means of the dark-field microscope has seldom been accomplished before the 5th day. The organisms are most abundant on the 6th to the 7th day, but become fewer or completely disappear before death. In the meanwhile the number of organisms increases in the liver and kidney, from which they disappear as the jaundice and other symptoms become aggravated. When death occurs these organs seem to have lost most of the leptospira) and positive transfer by means of them is less certain. At the later stage of the disease the blood is often free from the organisms and ceases to be infective. Positive transmission with blood obtained from moribund animals is not impossible, however, even when no leptospira can be detected under the dark-field microscope. Footnotes Submitted: 16 May 1919
ETIOLOGY OF YELLOW FEVERNoguchi, Hideyo
doi: 10.1084/jem.30.2.95pmid: 19868353
By the inoculation of guinea pigs intraperitoneally with the emulsions of kidneys from wild rats and mice captured in Guayaquil, it was found that 67 per cent of the wild rats tested harbored in their kidneys a leptospira which produced in guinea pigs symptoms and lesions identical with those produced by Leptospira icterohamorrhagia derived either from patients suffering from infectious jaundice in Japan or Europe, or from wild rats caught in New York. Immune sera were prepared in rabbits by injecting different strains of the Guayaquil leptospira. These sera had a marked agglutinating and disintegrating influence upon the homologous strains, and also, but often to a less pronounced degree, upon the strains of Leptospira icterohœmorrhagiœ from other sources. Pfeiffer's phenomenon was also found to be positive, and protection was demonstrated against infection with virulent cultures of strains of Leptospira icterohœmorrhagiœ . The same sera had no effect, or at most a very slight one, upon Leptospira icteroides . Guinea pigs inoculated with icteroides strains were not noticeably protected by the use of the immune sera prepared with the Guayaquil rat strains. Guinea pigs inoculated with killed cultures of the Guayaquil strains of leptospira proved to be resistant to a subsequent infection with heterologous as well as homologous strains of Leptospira icterohœmorrhagiœ . It is concluded, therefore, that the leptospira isolated from the kidneys of wild rats and mice in Guayaquil belongs to the group of Leptospira icterohœmorrhagiœ , and differs from Leptospira icteroides in its immunity reactions. No positive transmission was obtained with kidney material from bats and an opossum. Footnotes Submitted: 16 May 1919
INTESTINAL OBSTRUCTIONDragstedt, Lester R.; Dragstedt, Carl A.; McClintock, John T.; Chase, C. S.
doi: 10.1084/jem.30.2.109pmid: 19868348
1. It is impossible to sterilize the intestine by the use of chemical antiseptics even when these are applied directly to the mucosa of isolated segments. 2. The mucosa of the alimentary tract does not elaborate an internal secretion which is necessary to life, or a secretion which could be disturbed by the conditions of acute obstruction so as to account for the symptom complex of that condition. 3. The substances responsible for the toxemia in acute obstruction are produced by the action of intestinal bacteria on proteins or their split products. 4. An injury to the intestinal mucosa, particularly that resulting from disturbances of the blood supply to the intestine, greatly facilitates the absorption of these poisons. The work of Hartwell and his associates and that of Murphy and Brooks on this point are confirmed. Footnotes Submitted: 22 May 1919
A STUDY OF PNEUMOCOCCI REACTING WITH ANTIPNEUMOCOCCUS SERA OF TYPES I, II, AND III, WITH AN OBSERVATION OF A MUTATION OF ONE OF THE STRAINSClough, Mildred C.
doi: 10.1084/jem.30.2.123pmid: 19868349
In this paper are reported the results of a study of nine strains of pneumococci agglutinating with antipneumococcus sera of all three types (Nos. I, II, and III). Seven of the strains were the cause of serious or fatal infections in human beings. Morphologically they were typical pneumococci with characteristic growth on ordinary media. Most of the strains were soluble in bile, fermented inulin, and caused no precipitation on glucose ascitic fluid agar. Two of the strains, however, resembled streptococci in these three cultural characteristics, but have been regarded as pneumococci on account of their serological reactions. Variations in the cultural reactions occurred with several strains while they were under observation. The virulence of the strains varied greatly, some strains being almost non-pathogenic, and others killing mice in doses of 0.000001 cc. of a 24 hour broth culture. Antipneumococcus Sera I, II, and III agglutinated all the strains in fairly high dilution (1:8 to 1:64 or higher), while normal horse serum caused no agglutination. Antipneumococcus Sera I, II, and III stimulated active phagocytosis of all the strains, while no phagocytosis occurred in control preparations with normal horse serum. These strains elaborated a soluble substance in the body of inoculated mice which caused the formation of a precipitate when the peritoneal washings, cleared by centrifugalization, were added to the antipneumococcus sera of all three types. Antipneumococcus Sera I, II, and III protected mice equally well against 1,000 to 10,000 times the minimal lethal dose of the two strains with which protection tests could be carried out. Absorption of serum of Types I and II with the homologous pneumococcus removed the agglutinins and the bacteriotropins for all these strains. Absorption of these sera with Strains T and N removed the agglutinins and the bacteriotropins for the homologous strain only, and not for typical members of Type I or II, or for the other atypically agglutinable strains reported in this paper. The agglutinins concerned in the agglutination of these peculiar strains are therefore minor agglutinins. As shown not only by agglutination tests, but also by protection tests and agglutinin absorption tests, these organisms bear the same relation to Types I, II, and III, as do atypical Type II strains to Type II. Immune sera were prepared with these strains, and each strain was tested with all the immune sera by means of phagocytic and agglutinative reactions. In general, the strains were found to be serologically distinct, though some interrelationships existed between Strains V and R, and between Strains H, F, and N. These sera had no activity towards strains belonging to Type I or II, or atypical Type II. A mutation occurred in one of the strains, B, while it was under observation. On isolation this strain had the cultural reactions of a typical pneumococcus, and had the phagocytic and agglutinative reactions of an atypical Type II. After 6 months cultivation on blood agar its serological reactions changed, and it became actively phagocyted and agglutinated in antipneumococcus sera of Types I, II, and III. Its cultural characteristics also changed, and it became bile-insoluble, did not ferment inulin, and caused precipitation in glucose ascitic fluid agar. At this time it caused an intense green discoloration at the base of the blood agar slants around the water of condensation. By repeated animal passages this strain was three times made to revert abruptly to its original form (atypical Type IIa), both in cultural and serological reactions. An immune serum was prepared to each form of the strain, and each serum acted strongly on the homologous form, but was without action on the heterologous form of the strain. This mutation suggests that these pneumococci reacting with all three types of antipneumococcus sera may represent primitive, relatively undifferentiated forms from which the fixed types may have arisen. Footnotes Submitted: 29 April 1919
STUDIES OF OXYGEN IN THE VENOUS BLOODLundsgaard, Christen
doi: 10.1084/jem.30.2.147pmid: 19868350
1. Determinations of the oxygen content and the oxygen unsaturation of the venous blood have been performed on patients with varying amounts of hemoglobin. 2. The oxygen unsaturation of the venous blood is independent of the oxygen capacity, unless the latter is reduced below the normal value for oxygen unsaturation (about 5 volumes per cent). In a polycythemic patient, for example, with 33.4 volumes per cent oxygen capacity (181 per cent hemoglobin), the venous oxygen content was. 28 volumes per cent, giving an unsaturation of 5.4 volumes per cent. Similarly, in an anemic patient with only 6.7 volumes per cent oxygen capacity (36 per cent hemoglobin), the venous oxygen was 1.5, giving an unsaturation of 5.2 volumes per cent. This means that the tissues extract from the blood all the oxygen they need with apparently equal readiness, regardless of whether the extraction leaves a great oxygen reserve in the blood as in polycythemia, or practically no reserve as in anemia. 3. The results seem to show that the resting organism does not increase its circulation until all the reserve oxygen is used. This means that the resting anemic organism does not need or use any compensation for its anemia until the hemoglobin has sunk below 30 per cent. Below that value the organism increases the blood flow in order to secure to the tissues the normal amount of oxygen. Footnotes Submitted: 23 May 1919
THE STREPTOCOCCI OF EQUINESJones, F. S.
doi: 10.1084/jem.30.2.159pmid: 19868351
The lower nasal mucosa and the pharynx of thirty eastern and twenty-three western horses have been examined for streptococci. Eight of the eastern horses carried non-hemolytic streptococci on the nasal mucosa. From the pharynx of six, non-hepiolytic streptococci were cultivated. The throats of eighteen contained strains of the hemolytic type. The nasal mucosa of the eastern horses failed to show hemolytic streptococci. Eight western horses carried non-hemolytic streptococci in the nasal passage; eight also harbored the hemolytic type. Twenty-two strains were isolated from the pharynx. Eleven were hemolytic. Among all the non-hemolytic nasal strains those capable of fermenting mannite predominate. Those of the non-hemolytic types from the pharynx of both classes of horses may or may not ferment lactose but all do ferment either raffinose or inulin. In no instance have any of the non-hemolytic types proved pathogenic for mice. The hemolytic strains from the nasal mucosa of the western horses were all of the Streptococcus py genes type. They were pathogenic for mice and rabbits. One strain from the pharynx of an eastern horse and eight from the throats of the western horses were of the same species. All the others corresponded closely in their fermentation reactions with non-hemolytic streptococci from the same region. The streptococci from pathological sources were all hemolytic. They have fallen into two groups; the larger group ( Streptococcus pyogenes ) produced acid in dextrose, lactose, saccharose, maltose, milk, and salicin but failed to change the reaction of broth containing raffinose, inulin, or mannite. The streptococci of the smaller group ( Streptococcus equi ) differ only in their inability to ferment lactose or acidulate milk. Both types are pathogenic for mice. Rabbits are usually more resistant. Streptococcus pyogenes has been isolated from eighteen of twenty-two cases of influenza, three of six cases of strangles, and from eight of nine abscesses. Streptococcus equi was observed in four horses suffering from influenza and five others affected with strangles. This species was also found in an abscess and associated with both rhinitis and pharyngitis. Footnotes Submitted: 12 May 1919