of 1 /1
345 form of jaundice after birth appears to be as follows : give intramuscular blood at once and repeat in a few hours; if the condition fails to respond (as shown by hemoglobin estimations if full blood investigation is impossible) make arrangements for intravenous transfu- sion of matched blood (itself a by no means easy pro- cedure) ; if the downward progress continues splenectomy offers a reasonable chance of cure. WHEN DOG EATS DOG IT has been known for a long time that some micro- organisms produce substances antagonistic towards pathogenic bacteria, but until lately few attempts have been made to isolate these substances and study their biological and chemical properties. Dubos 1 isolated from the soil a gram-positive, spore-forming organism, later identified with Bacillus brevis, which produces powerful bactericidal agents. Originally it was believed that the bactericidal agent isolated from culture filtrates in crystalline form represented a single, homogeneous compound which was termed gramicidin, but later it was found to consist of two bactericidal substances which were both obtained in crystalline state-grhrnicidin, especially effective against gram-positive organisms, and tyrocidine, acting against gram-negative organisms as well. In vivo, gramicidin was shown to protect mice against pneumococcal infections and against infections with group A and group C streptococci under certain con- ditions which did not differ essentially from the in-vitro conditions in which the substance had been shown to be bactericidal. Given by the intravenous route gramicidin is almost completely inactive against systemic infections.2 It is highly toxic to animals. Tyrocidin is ineffective against bacterial infections in vivo ; it is haemolytic.2 Dubos and Hotchkiss found that a number of soil organ- isms produced substances similar to or identical with gramicidin and tyrocidin. Nothing is known yet about the chemical structure of these. J. C. Hoogerheide 3 des- cribed a crystalline antibacterial substance isolated from a soil organism, which according to its chemical and bio- logical properties seems to be identical with gramicidin ; it is now being tried out clinically in Philadelphia under the name HI; only local application is so far practicable because of its toxicity, but results are favourable. Also from’ the soil, Waksmann and Woodruff 4 isolated a chromogenic actinomyces (Actinomyces antibioticus) from which they obtained two antibacterial substances, actinomycin A and B. Actinomycin A is bright red, inhibits the growth of many bacteria in great dilution, but is very toxic to laboratory animals. It is mainly bacteriostatic, whereas actinomycin B, which is colour- less, is bactericidal. The chemical nature of these substances also has not been established. The nature of the antibacterial substances, produced by Pseudomonas pyocyanea, known for forty years since the work of Emmerich and Loeb 5 as " pyocyanase " has been reinvestigated by Schoental.6 She confirmed the bactericidal action of these substances on Vibrio cholerce, Staphylococcus aureus and many other organ- isms and showed that it was due to at least three frac- tions, the blue pigment pyocyanine, its breakdown pro- duct K-oxyphenazine, and a third colourless, chloroform- soluble principle, most easily extractable from old culture fluids. This last substance is bacteriolytic towards V. cholerae, thick suspensions of which are converted into a gel. In contrast to the original assumption of Emmerich and Loeb none of the antibacterÌI&bgr;l substances produced by Pe. pýocyanea are enzymes ; therefore the 1. Dubos, R. J. Proc. Soc. exp. Biol. N.Y. 1939, 40, 311 ; J. exp. Med. 1939, 70, 1, 289. 2. J. exp. Med. 1941, 73, 629. 3. J. Franklin Inst. 1940, 229, 677 ; J. Bact. 1940, 40, 325. 4. Waksman, S. A. and Woodruff, H. B. J. Bact. 1940, 40, 581 ; Proc. Soc. exp. Biol. N.Y. 1940, 45, 609 ; J. Bact. 1941, 41, 32. 5. Zbl. Bakt. 1899, 26, 237 ; 1901, 31, 1. 6. Schoental, R. Brit. J. exp. Path. 1941, 22, 137. term pyocyanase does not seem to be justified for any of them. A good deal is known about the chemical nature of pyocyanine and oc-ogyphenazine ; their antibacterial action is probably much the same as that of other bactericidal dyes of similar chemical constitution. The chemical nature of the chloroform-soluble colourless bacteriolytic substance remains to be investigated. The antibacterial substances from actinomyces strains isolated by Waksmann and Woodruff differ from another antibacterial agent obtained from actinomyces strains, actinomycetin, which forms the subject of many papers by Gratia and others.’ This substance, which acts against a number of gram-positive and gram-negative bacteria, and lyses a number of them, is a protein and belongs most probably to the class of bacteriolytic enzymes of the lysozyme type. Now Chain, Florey 8 and their colleagues have investi- gated the possibilities of penicillin, isolated from the mould Penicillium notatum. In the state of purity used in their biological and therapeutic experiments it is a yellow substance, easily soluble in water. It is not bactericidal, but even when very dilute (I : 2,000,000) it inhibits the growth of many pathogenic organisms, such as Staph. aureus, Streptococcus pyogenes, meningo- coccus, gonococcus, Clostridium qvelchii, B. anthracis and others. It differs from all the other anti- bacterial substances isolated from micro-organisms and, indeed from most antiseptics known, by its very low toxicity. Laboratory animals infected with Cl. septique, Staph. aureus and Strep. pyogenes were cured and the . results of a number of clinical trials are promising. Here again we have yet to learn its chemical composition. PSYCHIATRY IN THE SWISS ARMY THANKS to. the work of Forel, Bleuler and Jung, psychiatry is more advanced in Switzerland than in most European countries. Its importance in practical medi. cine is well recognised and psychiatric principles have penetrated into law, education and other fields of public life. Their application to military medicine is illustrated in three recent articles.9 Though the country is not at war, the army is in a state of constant full mobilisation- very different from the transient service of a few months each year which is customary in peace-time. Mental and psychological cases are common, amounting-so Dr. R. Brun estimates in the first article-to one in every sixteen admissions to the base hospital. This figures, he thinks, is if anything too low, because cases in the medical and surgical wards are often not recognised as psychological. Like the authors of the two remaining articles-Dr. M. Boss and Dr. Kurt Binswanger-he urges the need for closer cooperation between consultants so that cases in which neurotic symptoms are grafted on the residue of an organic illness-healed gastric ulcer, or an attack of sciatica or lumbago-will not be wrongly diagnosed and thus wrongly treated. Boss cautions his fellow psychiatrists about their approach to their medical colleagues : physicians, he reminds them, are descend- ants of the old medicine-men, and demi-gods are jealous of their godhead. This is a caution which might well work both ways, mutual forbearance achieving harmoni- ous liaison between physician and psychiatrist. Psychiatric cases are treated in special wards in the Swiss base hospitals ; there is also a psychiatric clinic, attached to each group command, in which cases sent from the unit can be examined and treated, sent to military boards, or otherwise disposed of. Early psychotics, neurotics and psychopaths form the bulk of the patients ; in most of them the illness has been present before they were called up, but symptoms have been evoked or exacerbated by the strict conditions of military 7. Gratia, A. and others, C.R. Soc. Biol. 1924, 91, 1442 ; 1925, 97, 461, 1125; 128, 1172. 8. Lancet, 1940. 2, 226 ; 1941, 2, 177. 9. Schweiz. med. Wschr. June 7, 1941, pp. 701, 707 and 711.

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345

form of jaundice after birth appears to be as follows :give intramuscular blood at once and repeat in a fewhours; if the condition fails to respond (as shown byhemoglobin estimations if full blood investigation is

impossible) make arrangements for intravenous transfu-sion of matched blood (itself a by no means easy pro-cedure) ; if the downward progress continues splenectomyoffers a reasonable chance of cure.

WHEN DOG EATS DOG

IT has been known for a long time that some micro-organisms produce substances antagonistic towards

pathogenic bacteria, but until lately few attempts havebeen made to isolate these substances and study theirbiological and chemical properties. Dubos 1 isolatedfrom the soil a gram-positive, spore-forming organism,later identified with Bacillus brevis, which producespowerful bactericidal agents. Originally it was believedthat the bactericidal agent isolated from culture filtratesin crystalline form represented a single, homogeneouscompound which was termed gramicidin, but later it wasfound to consist of two bactericidal substances whichwere both obtained in crystalline state-grhrnicidin,especially effective against gram-positive organisms, andtyrocidine, acting against gram-negative organisms aswell. In vivo, gramicidin was shown to protect miceagainst pneumococcal infections and against infectionswith group A and group C streptococci under certain con-ditions which did not differ essentially from the in-vitroconditions in which the substance had been shown to bebactericidal. Given by the intravenous route gramicidinis almost completely inactive against systemic infections.2It is highly toxic to animals. Tyrocidin is ineffectiveagainst bacterial infections in vivo ; it is haemolytic.2Dubos and Hotchkiss found that a number of soil organ-isms produced substances similar to or identical withgramicidin and tyrocidin. Nothing is known yet aboutthe chemical structure of these. J. C. Hoogerheide 3 des-cribed a crystalline antibacterial substance isolated froma soil organism, which according to its chemical and bio-logical properties seems to be identical with gramicidin ;it is now being tried out clinically in Philadelphia underthe name HI; only local application is so far practicablebecause of its toxicity, but results are favourable. Alsofrom’ the soil, Waksmann and Woodruff 4 isolated achromogenic actinomyces (Actinomyces antibioticus) fromwhich they obtained two antibacterial substances,actinomycin A and B. Actinomycin A is bright red,inhibits the growth of many bacteria in great dilution,but is very toxic to laboratory animals. It is mainlybacteriostatic, whereas actinomycin B, which is colour-less, is bactericidal. The chemical nature of thesesubstances also has not been established.The nature of the antibacterial substances, produced

by Pseudomonas pyocyanea, known for forty years sincethe work of Emmerich and Loeb 5 as " pyocyanase

" hasbeen reinvestigated by Schoental.6 She confirmed thebactericidal action of these substances on Vibriocholerce, Staphylococcus aureus and many other organ-isms and showed that it was due to at least three frac-tions, the blue pigment pyocyanine, its breakdown pro-duct K-oxyphenazine, and a third colourless, chloroform-soluble principle, most easily extractable from old culturefluids. This last substance is bacteriolytic towardsV. cholerae, thick suspensions of which are convertedinto a gel. In contrast to the original assumption ofEmmerich and Loeb none of the antibacterÌI&bgr;l substancesproduced by Pe. pýocyanea are enzymes ; therefore the

1. Dubos, R. J. Proc. Soc. exp. Biol. N.Y. 1939, 40, 311 ; J. exp.Med. 1939, 70, 1, 289.

2. J. exp. Med. 1941, 73, 629.3. J. Franklin Inst. 1940, 229, 677 ; J. Bact. 1940, 40, 325.4. Waksman, S. A. and Woodruff, H. B. J. Bact. 1940, 40, 581 ;

Proc. Soc. exp. Biol. N.Y. 1940, 45, 609 ; J. Bact. 1941, 41, 32.5. Zbl. Bakt. 1899, 26, 237 ; 1901, 31, 1.6. Schoental, R. Brit. J. exp. Path. 1941, 22, 137.

term pyocyanase does not seem to be justified for any ofthem. A good deal is known about the chemical natureof pyocyanine and oc-ogyphenazine ; their antibacterialaction is probably much the same as that of otherbactericidal dyes of similar chemical constitution. Thechemical nature of the chloroform-soluble colourlessbacteriolytic substance remains to be investigated.The antibacterial substances from actinomyces strainsisolated by Waksmann and Woodruff differ from anotherantibacterial agent obtained from actinomyces strains,actinomycetin, which forms the subject of many papersby Gratia and others.’ This substance, which acts

against a number of gram-positive and gram-negativebacteria, and lyses a number of them, is a protein andbelongs most probably to the class of bacteriolyticenzymes of the lysozyme type.Now Chain, Florey 8 and their colleagues have investi-

gated the possibilities of penicillin, isolated from themould Penicillium notatum. In the state of purity usedin their biological and therapeutic experiments it is a

yellow substance, easily soluble in water. It is notbactericidal, but even when very dilute (I : 2,000,000)it inhibits the growth of many pathogenic organisms,such as Staph. aureus, Streptococcus pyogenes, meningo-coccus, gonococcus, Clostridium qvelchii, B. anthracisand others. It differs from all the other anti-bacterial substances isolated from micro-organismsand, indeed from most antiseptics known, by its very lowtoxicity. Laboratory animals infected with Cl. septique,Staph. aureus and Strep. pyogenes were cured and the

. results of a number of clinical trials are promising.Here again we have yet to learn its chemical composition.

PSYCHIATRY IN THE SWISS ARMY

THANKS to. the work of Forel, Bleuler and Jung,psychiatry is more advanced in Switzerland than in mostEuropean countries. Its importance in practical medi.cine is well recognised and psychiatric principles havepenetrated into law, education and other fields of publiclife. Their application to military medicine is illustratedin three recent articles.9 Though the country is not atwar, the army is in a state of constant full mobilisation-very different from the transient service of a few monthseach year which is customary in peace-time. Mentaland psychological cases are common, amounting-soDr. R. Brun estimates in the first article-to one in everysixteen admissions to the base hospital. This figures, hethinks, is if anything too low, because cases in themedical and surgical wards are often not recognised aspsychological. Like the authors of the two remainingarticles-Dr. M. Boss and Dr. Kurt Binswanger-heurges the need for closer cooperation between consultantsso that cases in which neurotic symptoms are grafted onthe residue of an organic illness-healed gastric ulcer, oran attack of sciatica or lumbago-will not be wronglydiagnosed and thus wrongly treated. Boss cautions hisfellow psychiatrists about their approach to their medicalcolleagues : physicians, he reminds them, are descend-ants of the old medicine-men, and demi-gods are jealousof their godhead. This is a caution which might wellwork both ways, mutual forbearance achieving harmoni-ous liaison between physician and psychiatrist.

Psychiatric cases are treated in special wards in theSwiss base hospitals ; there is also a psychiatric clinic,attached to each group command, in which cases sentfrom the unit can be examined and treated, sent tomilitary boards, or otherwise disposed of. Earlypsychotics, neurotics and psychopaths form the bulk ofthe patients ; in most of them the illness has been presentbefore they were called up, but symptoms have beenevoked or exacerbated by the strict conditions of military7. Gratia, A. and others, C.R. Soc. Biol. 1924, 91, 1442 ; 1925, 97,

461, 1125; 128, 1172.8. Lancet, 1940. 2, 226 ; 1941, 2, 177.9. Schweiz. med. Wschr. June 7, 1941, pp. 701, 707 and 711.